Pediatrics Final 2.1

1. Cardiology

I. Congenital Heart Defects (CHD) & Acquired Conditions

• Patent Ductus Arteriosus (PDA)
  • Large PDA Findings:
    • Blood pressure example: 100/45 mmHg (wide pulse pressure).
    • Bounding pulses.
    • Displaced apical impulse.
    • Left axis deviation on ECG.
    • Cardiomegaly on CXR.
    • Continuous murmur at the left upper sternal border/left subclavicular area.
    • Not typically associated with right atrial dilatation on CXR.
  • Physiology: Leads to wide pulse pressure and prominent (bounding) peripheral pulses due to continuous runoff of blood from aorta to pulmonary artery.
  • Management (when PDA is vital): For cyanotic CHDs dependent on PDA for pulmonary or systemic blood flow, administer Prostaglandin E1 (PGE1) to keep the ductus arteriosus open.

• Ventricular Septal Defect (VSD)
  • Large VSD Presentation:
    • Symptoms: Progressive tachypnea, poor feeding, failure to thrive, cool extremities, intercostal retractions.
    • Auscultation: Holosystolic murmur on the left sternal border (due to VSD flow), loud second heart sound (P2 component due to pulmonary hypertension).
    • Pathophysiology:
      • Intercostal retractions are due to pulmonary vascular congestion.
      • Liver enlargement can occur due to congestive heart failure.
    • ECG/CXR: Left atrial dilatation on ECG, cardiomegaly on CXR.
    • Symptoms typically start after 4-8 weeks with dyspnea.
  • Small VSD: Often presents with a loud, high-pitch pansystolic murmur heard best at the apex or lower left sternal border; the murmur becoming louder can indicate the VSD is getting smaller.
  • Failure to gain weight can be due to increased metabolic demand and poor feeding.
  • Not typically associated with wide pulse pressure (unlike PDA).

• Atrial Septal Defect (ASD)
  • Clinical Features:
    • Often asymptomatic.
    • Auscultation: Soft mid-systolic ejection murmur (grade 2/6) at the left upper sternal border (pulmonic area) or left second intercostal space, with wide and fixed splitting of the second heart sound (S2).
    • Gallop rhythm is not a typical finding of ASD.
  • Complications (Large Secundum ASD):
    • Dilatation of the right atrium (RA) and right ventricle (RV).
    • Risk of tachyarrhythmias (e.g., atrial fibrillation) in adulthood.
    • Risk of paradoxical emboli, increasing with age.
    • Risk of Eisenmenger syndrome is rare and occurs late in uncorrected large defects.
    • Large defects often require closure even if asymptomatic.
  • CXR: May show enlarged RA and increased pulmonary markings.
  • Not associated with left ventricular dilatation (causes RV volume overload).

• Tetralogy of Fallot (TOF)
  • Components:
    1. Ventricular Septal Defect (VSD)
    2. Pulmonary Stenosis (PS) (determines severity of cyanosis)
    3. Overriding Aorta
    4. Right Ventricular Hypertrophy (RVH)
  • Clinical Presentation:
    • Cyanosis: Varies with severity of PS; classically presents around 3-9 months.
    • Murmur: Loud, long, harsh systolic ejection murmur at the left sternal border (due to RV outflow tract obstruction/PS).
    • Right ventricular heave due to RVH.
    • Pulses are typically normal.
    • Cyanotic spells (“Tet spells”): Attacks of increased cyanosis, often precipitated by crying, feeding, or defecation.
  • CXR: Boot-shaped heart with decreased pulmonary vascular markings.
  • Factors Worsening Cyanosis: Exercise, fever, dehydration, travel to high altitude (due to decreased SVR or increased PVR).
  • Factors Improving Cyanosis: Squatting (increases SVR, promoting pulmonary blood flow).
  • Generally not associated with cardiomegaly on CXR unless other complications.

• Transposition of Great Arteries (TGA)
  • Presentation: Early and severe cyanosis in a newborn, often without a significant murmur unless associated defects (e.g., VSD, PDA) are present.
  • CXR: Classic finding is an “egg-on-a-string” appearance (narrow mediastinum with ovoid cardiac silhouette).
  • Survival: Often dependent on mixing at atrial level (PFO/ASD) or ductal level (PDA).

• Aortic Stenosis (AS)
  • Murmur: Systolic ejection murmur, typically loudest at the right upper sternal border, radiating to the suprasternal notch and carotid arteries.

• Coarctation of Aorta (CoA)
  • Clinical Features:
    • Hypertension in upper extremities.
    • Radio-femoral pulse delay and weaker/absent femoral pulses.
    • Displaced apical impulse, LVH on ECG.
    • Systolic murmur often heard best in the inter-scapular area (back).
  • CXR:
    • Rib notching (due to collateral circulation via intercostal arteries) in older children.
    • Cardiomegaly.
    • Not typically associated with a wide mediastinum.

• Tricuspid Atresia
  • Presentation: Cyanotic CHD.
  • ECG: Characteristic finding is left axis deviation (due to hypoplastic RV and relatively larger LV).
  • Physical Exam: May have a holosystolic murmur if VSD is present. No right ventricular heave (RV is hypoplastic); left ventricle is often enlarged.

• Hypoplastic Left Heart Syndrome (HLHS)
  • Survival is dependent on a patent ductus arteriosus for systemic circulation and a PFO for shunting.

• Truncus Arteriosus
  • Single arterial trunk arises from the heart, supplying systemic, pulmonary, and coronary circulations. Always associated with a VSD.
  • Leads to volume overload on LV and increased pulmonary vascular markings on CXR.

• Total Anomalous Pulmonary Venous Return (TAPVR)
  • Pulmonary veins drain into the right atrium or systemic veins instead of the left atrium.
  • Requires an interatrial communication (PFO/ASD) for survival.
  • CXR: May show “snowman” appearance (supracardiac type).

• Pulmonary Atresia with Intact Ventricular Septum
  • Survival dependent on PDA for pulmonary blood flow and PFO for RA to LA shunting.

II. Cardiovascular Physiology & General Principles

• Fetal Circulation:
  • Highest oxygenated blood is in the umbilical vein.
  • Blood moves from the pulmonary artery to the aorta via the ductus arteriosus.
  • The foramen ovale allows blood to move from the right atrium to the left atrium.
  • The right ventricle is dominant in fetal life, supplying two-thirds of combined ventricular output.

• Transition to Postnatal Circulation:
  • Pulmonary vascular resistance (PVR) is high at birth, decreases significantly in the first few weeks of life, reaching near-adult levels by 4-8 weeks.
  • Foramen ovale functionally closes shortly after birth, anatomically later.
  • Ductus arteriosus constricts and closes, typically within days to weeks.

• Early Life Cardiovascular Physiology:
  • Resting heart rate decreases with age.
  • Blood pressure is lowest at birth and gradually increases with age.
  • Normal BP of a preterm neonate is less than that of a full-term neonate.
  • A heart rate of 165/min in a crying 6-month-old is within normal limits (normal up to ~180/min).

• Cardiac Function & Output:
  • During increased metabolic demand, cardiac output increases via increased heart rate and stroke volume.
  • Low blood pressure is a late sign of decreased cardiac output.
  • Cardiac output is usually increased in patients with chronic anemia.
  • Cardiac output decreases with increasing afterload.
  • Sympathetic stimulation increases cardiac contractility.
  • In normal hearts, RV output equals LV output.
  • Cardiac output is determined by stroke volume and heart rate.

• Volume Overload:
  • Left Ventricular Volume Overload: Caused by PDA, VSD, aortic regurgitation, mitral regurgitation, truncus arteriosus.
  • Not caused by ASD (causes RV volume overload) or CoA (causes LV pressure overload).

• Heart Murmurs:
  • Innocent Murmurs: Common in children. Typically systolic, soft, vibratory, and change with position (e.g., disappears or diminishes when the child stands up). Reassurance is often the management.
  • Diastolic Murmurs: Always pathological. Causes include aortic regurgitation, pulmonary regurgitation, mitral stenosis, tricuspid stenosis. Not coarctation of aorta.
  • Continuous Murmur: e.g., PDA.

• Cyanosis in CHD:
  • Hyperoxia Test: Used to differentiate cardiac from pulmonary causes of cyanosis. In CHD, arterial PaO2 usually remains < 150 mmHg on 100% oxygen.
  • Management of Unstable Infant with Suspected Cyanotic CHD: Administer Prostaglandin E1 (alprostadil) to maintain ductal patency.

• Survival Shunts:
  • Patent Foramen Ovale (PFO) dependent lesions: Tricuspid atresia, TAPVR, HLHS, pulmonary atresia with intact ventricular septum.
  • Patent Ductus Arteriosus (PDA) dependent lesions: Pulmonary atresia, critical pulmonary stenosis, critical coarctation/interrupted aortic arch, HLHS, TGA (for mixing). Tricuspid atresia with no VSD always requires a PDA.

• Clubbing: A sign of chronic hypoxia, typically develops after several months. A 3-month-old is generally too young to show clubbing.

III. Heart Failure

• Causes in Infancy: Large VSD, large PDA, CoA, cardiomyopathies.

• Clinical Signs: Tachypnea, tachycardia, poor feeding, failure to thrive, hepatomegaly, diaphoresis with feeding, cool extremities, intercostal retractions.

• Management:
  • Diuretics (e.g., Lasix):
    • Electrolyte disturbances: Hypokalemia, hyponatremia, hypochloremia, metabolic alkalosis, hypercalciuria.
  • Inotropes (improve contractility): Dopamine, epinephrine, digoxin, milrinone.
  • Beta-blockers (e.g., propranolol): Negative inotropes; contraindicated in acute decompensated heart failure.
  • Viral Myocarditis with Heart Failure: Management includes oxygen, diuretics, and inotropic support. IV fluid bolus and beta-blockers are contraindicated.

• Cardiogenic Shock:
  • Worsening indicators: Decreased mixed venous oxygen saturation (e.g., central venous O2 sat from 60% to 45%).
  • Improvement indicators: Decreased serum lactate, increased urine output.

IV. Specific Diagnostic Points

• ECG in Tricuspid Atresia: Left axis deviation.

• Wide and Fixed Splitting of S2: Atrial Septal Defect (ASD).

• Boot-Shaped Heart on CXR: Tetralogy of Fallot (TOF).

• Egg-on-a-String CXR: Transposition of Great Arteries (TGA).

• Rib Notching on CXR: Coarctation of Aorta (in older children).

• Systolic Murmur Radiating Suprasternally (Right Upper Sternal Border): Aortic Stenosis.

• Opening Systolic Click (Right Side) with Radiation and Systolic Murmur: Pulmonary Stenosis.

• Holosystolic Murmur at Left Sternal Border, Loud P2, Cool Extremities, FTT (2 m/o): Ventricular Septal Defect (VSD).

V. Miscellaneous Cardiovascular Points

• Syncope/Sudden Loss of Consciousness with Exertion: Consider aortic stenosis, Long QT syndrome, hypertrophic cardiomyopathy (HOCM).

• Cardiomyopathy Compensatory Mechanisms: Increased heart rate, water retention (increased preload), increased sympathetic tone, increased angiotensin II levels. Polycythemia is a response to chronic hypoxia, not directly a compensatory mechanism for primary pump failure.

• Normal Cardiac Findings in 3-Month-Old: HR 180 when crying, capillary refill 1 sec, visible apical impulse. Louder S2 than S1 at upper sternal border is normal. BP 110/70 might be high for a 3-month-old.

• Umbilical Cord Anomaly (Single Umbilical Artery - one artery, one vein): Associated with an increased likelihood of congenital anomalies (especially renal and cardiac).

• Asymptomatic Systolic Murmur at LSB that Disappears on Standing: Innocent murmur.

• Eisenmenger Syndrome: A complication of large, uncorrected left-to-right shunts (VSD, ASD, PDA) leading to severe pulmonary hypertension and reversal of the shunt (right-to-left), causing cyanosis. It is a late complication, typically in late childhood or adulthood. Risk is lower and later in ASD compared to large VSDs or PDAs.

2. Respiratory

I. Infections

• Pneumonia
  • Common Causative Pathogens:
    • 4 months - 4 years: RSV is a common cause, Streptococcus pneumoniae is the most common bacterial cause.
    • Agammaglobulinemia: S. pneumoniae is a common cause of both otitis media and pneumonia.
    • School-aged children (>5 years): Mycoplasma pneumoniae and Chlamydophila pneumoniae are frequent bacterial pathogens. Mycoplasma is not common in early infancy.
  • Indications for Hospitalization:
    • Age < 6 months (not < 6 years).
    • Signs of respiratory distress.
    • Immune deficiency.
    • Lobar pneumonia with suspected resistance to beta-lactam antibiotics.
    • No response to oral antibiotics.
  • Mycoplasma Pneumonia: Drug of choice is a macrolide (e.g., erythromycin, azithromycin).
  • Staphylococcus aureus Pneumonia: Can be severe, associated with empyema and pneumatoceles (thin-walled, air-filled cysts on CXR).
  • Haemophilus influenzae type b (Hib): Significant cause of lobar pneumonia in unvaccinated children.
  • Viral Pneumonia: Viruses are a common cause of pneumonia in infancy, especially < 2 years (RSV, parainfluenza, influenza, adenovirus).

• Bronchiolitis
  • MCC: Respiratory Syncytial Virus (RSV).
  • Clinical Features: Tachypnea, wheezing, cough, subcostal/intercostal retractions, nasal flaring.
  • CXR Findings: Bilateral hyperinflation, atelectasis. Not decreased lung volume.
  • Course: Can take several weeks to resolve, especially cough and wheeze.
  • Complications: Apnea (especially in young infants/premature), respiratory failure. Secondary bacterial pneumonitis is not a common complication.
  • Long-term: RSV bronchiolitis in infancy may increase the risk of developing asthma later in life, but asthma itself is not an acute presentation of RSV.
  • Management: Supportive. Nebulized hypertonic saline may be used. Systemic corticosteroids, routine nebulized bronchodilators, and IV ceftriaxone are generally not recommended.

• Croup (Laryngotracheobronchitis)
  • MCC: Parainfluenza virus.
  • Clinical Features: Barking cough, inspiratory stridor, hoarseness. Onset is usually gradual/insidious, often preceded by URI symptoms.
  • Age: Most common in children 6 months to 3 years. Not more common in children older than 4 years.
  • Management: Corticosteroids (oral or nebulized), nebulized epinephrine for moderate/severe cases.
  • X-ray: Steeple sign on AP neck X-ray (subglottic narrowing).
  • If symptoms recur after treatment (no drooling, vaccinated): Could be persistence of viral infection or a new viral episode. Bacterial tracheitis (often S. aureus) should be considered if high fever, toxicity, and worsening distress develop after several days of croup-like illness.

• Epiglottitis
  • MCC (Historically): Haemophilus influenzae type b (Hib) - incidence dramatically reduced by Hib vaccine.
  • Clinical Features: Rapid/sudden onset (over hours), high fever, drooling, dysphagia, severe sore throat, toxic appearance, tripod positioning, inspiratory stridor, muffled voice. Cough is often absent or slight.
  • Diagnosis: Laryngoscopy in a controlled setting (OR) is definitive. Lateral neck X-ray may show “thumb sign.”
  • Management: Secure airway (intubation in OR), IV antibiotics (e.g., ceftriaxone). Avoid anxiety-provoking interventions or attempts to visualize pharynx outside controlled setting.
  • Aminoglycosides are not the drug of choice.
  • Coryza (runny nose) is not a typical preceding feature.

• Bacterial Tracheitis
  • Serious bacterial infection of trachea, often following viral croup. MCC: S. aureus.
  • Presents with high fever, toxicity, stridor, copious purulent secretions.
  • Can be clinically similar to epiglottitis but often has more productive cough.

• Sinusitis (Acute Bacterial Rhinosinusitis)
  • Common predisposing factors: Viral URI, allergic rhinitis.
  • Symptoms: Persistent nasal discharge (often purulent), cough (wet or dry, often worse at night), facial pain/pressure, fever. Thick mucus secretions are a key feature.
  • Diagnosis: Primarily clinical. Imaging (CT/plain film) is not routinely needed; normal imaging does not exclude diagnosis if clinical suspicion is high. CT is not required for diagnosis in uncomplicated cases.
  • Treatment: Amoxicillin or amoxicillin-clavulanate is first-line.
  • If unresponsive to amoxicillin (e.g., 10-day course): Consider antimicrobial-resistant sinusitis or other causes like nasal foreign body.

• Pharyngitis
  • Group A Streptococcus (GAS): Penicillin remains effective. Treatment decreases risk of rheumatic fever.
  • Differentiation between viral and bacterial is often difficult by physical exam alone.
  • Bacterial pharyngitis often has sudden onset and anterior cervical adenopathy.
  • Acute glomerulonephritis can follow streptococcal pharyngitis OR streptococcal skin infection (impetigo).

II. Non-Infectious Respiratory Conditions

• Asthma
  • Pulmonary Function Tests (PFTs) during exacerbation:
    • Decreased FEV1, FEV1/FVC ratio, PEFR, FEV 25-75%.
    • Increased Residual Volume (RV), Functional Residual Capacity (FRC). Total Lung Capacity (TLC) may be normal or increased. Not decreased TLC.
  • Controller Therapy Indication (GINA): Using SABA (reliever) more than two days per week.
  • Triggers (Extrinsic/Allergic): Pollen (e.g., olive tree), cat dander, dust mites, molds. Cold air is a non-allergic trigger. Cow’s milk is a food allergen and can worsen asthma in sensitized individuals, but not a typical inhalant trigger for extrinsic asthma.
  • Acute Exacerbation:
    • Early stages: Tachypnea leads to respiratory alkalosis (PaCO2 falls).
    • Severe/Late stages (Impending Respiratory Failure): Hypercarbia (PaCO2 rises) and respiratory acidosis. PaCO2 of 50 torr is a concerning sign. Silent chest is an ominous sign.
    • Management (Severe Acute): SABA nebulization, systemic corticosteroids (e.g., IV hydrocortisone). Inhaled corticosteroids are for long-term control, not primary acute treatment. Magnesium sulfate IV can be used in severe cases.
  • Predictive Risk of Future Asthma: Skin prick test for inhaled allergens is a useful investigation.
  • Most common trigger for asthma in young children (0-4 years): Upper respiratory infections.

• Cystic Fibrosis (CF)
  • Genetics: Autosomal recessive. Defect in the CFTR gene (Chloride channel) on chromosome 7. Affects males and females equally. Affected patients have two defective CFTR genes.
  • Diagnosis:
    • Sweat Chloride Test: Gold standard. False negatives can occur with hypoproteinemia. Test results do not normalize with treatment. Monitoring sweat chloride is not used to assess adequacy of management. Accurate in newborns.
    • Genetic Testing: Confirms diagnosis by identifying CFTR mutations. Does not diagnose 100% of cases as many mutations exist.
    • Newborn Screening: Often includes Immunoreactive Trypsinogen (IRT). Elevated IRT is a screening test, requires confirmation.
    • Early Manifestation: Meconium ileus.
  • Pulmonary Manifestations:
    • Chronic wet cough, recurrent respiratory infections, bronchiectasis, pansinusitis.
    • Pathogens: Staphylococcus aureus common early, Pseudomonas aeruginosa associated with progressive lung disease.
    • PFTs: Typically show an obstructive pattern early (decreased FEV1, FEV1/FVC). Restrictive pattern may develop later due to fibrosis.
    • Complications: Pneumothorax.
    • Recurrent respiratory infections are primarily due to thick, viscous mucus and impaired mucociliary clearance, not a primary immune deficiency.
  • Gastrointestinal Manifestations:
    • Pancreatic insufficiency leading to fat malabsorption (steatorrhea) and protein malabsorption.
    • Failure to thrive, rectal prolapse.
    • Salt wasting (especially in hot weather).
    • Cholestasis, biliary cirrhosis.
    • Distal intestinal obstruction syndrome (DIOS).
    • Not typically perianal abscess.
  • Other Manifestations: CF-related diabetes (insulin-dependent hyperglycemia), delayed puberty (not precocious), nasal polyposis.
  • Treatment:
    • Pulmonary therapy (airway clearance), antibiotics for exacerbations (e.g., aminoglycoside + anti-pseudomonal penicillin like ticarcillin for Pseudomonas).
    • Pancreatic enzyme replacement, fat-soluble vitamin supplementation (A, D, E, K).

• Laryngomalacia
  • MCC of persistent stridor in infants.
  • Inspiratory stridor, often worse when supine, crying, or feeding.
  • Usually congenital and improves with age. Not very common after surgery.
  • Can be aggravated by GERD.

• Choanal Atresia
  • Congenital obstruction of posterior nasal passage.
  • Presents as neonatal respiratory distress/cyanosis that improves with crying (as baby mouth-breathes) and worsens with feeding/pacifier use.

• Respiratory Resistance in Infants: Major contributor is the nasal airway and mouth.

• Wheezing Causes in Children: Asthma, cystic fibrosis, viral bronchiolitis, gastroesophageal reflux disease. Not lactose intolerance.

• Transient Tachypnea of the Newborn (TTN)
  • Benign, self-limiting respiratory distress in term/near-term newborns.
  • Due to delayed clearance of fetal lung fluid.
  • Onset usually within hours of birth, resolves by 48-72 hours.
  • More common after Cesarean section.
  • CXR: Perihilar streaking, fluid in fissures, hyperinflation. Air bronchograms are not typical (more RDS).
  • Surfactant therapy is not indicated.

• Primary Ciliary Dyskinesia (PCD)
  • Can present with chronic wet cough, recurrent sinusitis/otitis, bronchiectasis, situs inversus (e.g., dextrocardia).
  • Diagnosis can be aided by electron microscopy of cilia.

III. General Respiratory Points

• Atypical Pneumonia: Mycoplasma pneumoniae is a cause.

• Total Respiratory Resistance in Infants: Primarily due to nasal airway and mouth.

• Upper Airway Obstruction (Acute): Causes include croup, laryngitis, bacterial tracheitis, epiglottitis. Bronchiolitis causes lower airway obstruction.

• Normal imaging studies (CT or plain film) of the paranasal sinuses do not exclude the diagnosis of acute bacterial rhinosinusitis if clinical criteria are met.

• Consolidation (Physical Exam Finding): Causes increased tactile vocal fremitus (not decreased).

3. Gastrointestinal

I. Infant Nutrition

• Breast Milk
  • Composition:
    • Most antigenic part: Protein component.
    • Carbohydrate: Lactose (major component).
    • Protein: Whey-dominant (whey:casein ratio higher than cow’s milk, e.g., 60:40), easier to digest.
    • Fat: Long-chain triglycerides, provides ~50% of calories.
    • Vitamins/Minerals: Deficient in Vitamin D. Vitamin K is low (newborns get Vit K shot). Iron content is low but highly bioavailable. Vitamin and mineral content can vary with maternal diet.
    • Caloric content: Approx. 67 kcal/100 ml.
    • Amount and composition vary according to the infant’s age and during a single feed (foremilk/hindmilk).
  • Benefits:
    • Optimal nutrition.
    • Easily digestible.
    • Reduced risk of infections (GI, respiratory, otitis media) due to antibodies (IgA), lactoferrin, etc.
    • Decreased risk of necrotizing enterocolitis (NEC).
    • Reduced risk of SIDS.
    • Promotes mother-infant bonding.
    • May decrease risk of asthma, eczema, and obesity.
    • Does not inherently protect from hemorrhagic disease of the newborn (requires Vitamin K supplementation at birth).
  • Breastfeeding Practices:
    • Initiate immediately after birth.
    • Colostrum is highly beneficial.
    • Feed on demand.
    • Vitamin D supplementation (400 IU/day) is recommended for all exclusively breastfed infants.
    • Iron supplementation typically starts at 4-6 months for exclusively breastfed infants.

• Cow’s Milk (Fresh): Introduction should be delayed until 12 months of age.

• Low-Fat Milk: Introduction recommended at 24 months of age.

• Introducing Solid Foods: Recommended around 6 months of age.

• Formula Feeding:
  • Soy Formula: Used for galactosemia, true lactose intolerance (rare), or vegetarian families. Carbohydrate is usually sucrose or corn syrup solids (lactose-free). Contains adequate vitamins if properly formulated. Some cross-reactivity with cow’s milk protein allergy (10-15%).
  • Hydrolyzed Formulas (Extensively or Partially): Used for cow’s milk protein allergy. Amino acid-based formulas for severe allergy.
  • Lactose-free formula is not a primary treatment for cow’s milk protein allergy (allergy is to protein, not lactose).

• Evaluation of Adequacy of Nutrition: Consistent and adequate weight gain is the best indicator. Urine output and head circumference are also monitored.

• Cow’s Milk Protein Allergy (CMPA):
  • Symptoms: Atopic dermatitis, chronic cough, FTT, vomiting, diarrhea (can be bloody), irritability.
  • Allergy is to whey and/or casein proteins.
  • Management (breastfed): Maternal elimination of dairy.
  • Management (formula-fed): Switch to extensively hydrolyzed or amino acid-based formula. Response usually seen within 2-3 days.

II. Gastrointestinal Disorders

• Acute Diarrhea & Gastroenteritis
  • Causes: Rotavirus (common), Norovirus, bacteria (Salmonella, Shigella, Campylobacter, E. coli). Amoeba can cause acute diarrhea.
  • Not a cause of acute diarrhea lasting one week: Primary lactose intolerance (typically chronic or secondary).
  • Management:
    • Oral Rehydration Solution (ORS) is the cornerstone.
    • Continue breastfeeding/age-appropriate diet.
    • Avoid high-carbohydrate drinks (can worsen osmotic diarrhea).
    • Antibiotics only if specific bacterial cause identified and indicated (e.g., Shigella). Not routinely for EHEC O157:H7 (risk of HUS).
  • Complications: Dehydration (most important).
  • Young infants are more severely affected by dehydration. Most cases are self-limited. Specific diagnostic tests usually not needed.

• Chronic Diarrhea
  • Causes: Giardia lamblia, cystic fibrosis (steatorrhea), lactose intolerance, celiac disease.
  • Stool pH < 5.5 and presence of reducing substances: Suggests carbohydrate malabsorption (e.g., lactose intolerance), not protein malabsorption.
  • Secretory diarrhea: Stool output is not dependent on oral intake (persists with fasting).

• Cystic Fibrosis (GI Manifestations):
  • Failure to thrive (FTT) due to fat malabsorption (pancreatic insufficiency).
  • Steatorrhea (bulky, foul-smelling, greasy stools).

• Celiac Disease
  • Immune-mediated enteropathy triggered by gluten (wheat, barley, rye). Rice is safe.
  • Presentation: Diarrhea, FTT, abdominal distension, short stature, irritability. Can present with constipation. Associated with Type 1 DM, autoimmune thyroiditis, Trisomy 21.
  • Diagnosis: Serology (Anti-TTG IgA, EMA IgA), small bowel biopsy (gold standard).
  • Treatment: Lifelong gluten-free diet. Sensitivity to gluten does not resolve.
  • Complications: Malabsorption (iron, folate, Vit D, Vit K deficiency - leading to anemia, osteomalacia, bleeding tendency).
  • Increased risk groups: Type 1 DM, Trisomy 21, first-degree relatives. Not Trisomy 13.

• Biliary Atresia:
  • Presents with neonatal cholestasis (conjugated hyperbilirubinemia), acholic stools, dark urine, FTT.
  • FTT is due to fat malabsorption (lack of bile for digestion).

• Rotavirus Infection:
  • Most common cause of severe diarrhea in young children.
  • Induces osmotic diarrhea.
  • Highly contagious.
  • Dehydration is the most important complication.
  • Not typically associated with increased stool polymorphonuclear cells (PMNs) unless secondary bacterial infection.
  • Best diagnostic test: Stool antigen test.

• Organic Abdominal Pain Indicators: Pain awakening the patient at night.

• Failure to Thrive (FTT):
  • Type 1 FTT (Weight <3rd percentile, normal Ht/HC): Often due to inadequate caloric intake or malabsorption (e.g., incorrect formula prep, persistent diarrhea, vomiting, poor social situation). Chromosomal abnormalities usually cause Type 2 or 3 FTT.
  • Cystic Fibrosis: Can cause Type 2 FTT (weight and height affected).

III. Miscellaneous GI Points

• Hepatitis B Carrier Mother: Newborn should receive Hepatitis B vaccine AND Hepatitis B Immune Globulin (HBIG) within 12 hours of birth, followed by completion of the vaccine series. Breastfeeding is not contraindicated if infant receives prophylaxis.

• Reducing Substances in Urine: Suggests disorders like galactosemia.

• Bloody Diarrhea: Caused by Shigella, Salmonella, Campylobacter, EHEC, Entamoeba histolytica.

• Necrotizing Enterocolitis (NEC):
  • Most common GI emergency in neonates, especially premature infants.
  • Rate of occurrence inversely related to gestational age.
  • Exact etiology unknown, multifactorial (ischemia, infection, inflammation). Infectious etiology is a contributing factor, not necessarily the sole “most likely causative factor.”
  • Can lead to strictures.
  • Presents with abdominal distension, bloody stools, intestinal perforation (late), hypoactivity, jaundice.

4. Endocrine

I. Growth & Development

• Normal Growth Parameters:
  • Weight: Doubles by 4-5 months, triples by 1 year.
  • Height (Length): Increases by ~25 cm in the 1st year. Doubles by approx. 4 years.
  • Head Circumference (HC): Increases by ~12 cm in the 1st year.
  • Birth Averages: Weight 2.5-4.2 kg (female avg ~3.2 kg, can be 3.5 kg general), height 48-52 cm.
  • Upper to Lower Segment Ratio: At birth ~1.7:1 (torso-dominant). Reaches adult proportions (~0.9-1:1) after puberty.
  • Newborns may lose up to 10% of birth weight in the first week, regained by 10-14 days.

• Short Stature
  • Causes:
    • Constitutional Delay of Growth and Puberty (CDGP): Delayed bone age, normal growth velocity for bone age, family history of similar pattern, eventual normal adult height. More common in boys.
    • Familial (Genetic) Short Stature: Normal bone age, normal growth velocity, family history of short stature, short adult height.
    • Endocrinopathies: Growth hormone deficiency (GHD), hypothyroidism, Cushing’s syndrome.
    • Genetic/Chromosomal Syndromes: Turner syndrome, Down syndrome. Klinefelter syndrome usually results in tall stature.
    • Systemic Diseases: Celiac disease, chronic renal disease, IBD.
    • Skeletal Dysplasias.
    • Psychosocial dwarfism.
    • Nutritional obesity does not cause short stature; often associated with initially taller stature and advanced bone age.
  • Evaluation: Growth velocity, bone age, family history, systemic review. Random GH level is not useful (GH is pulsatile); IGF-1/IGFBP-3 are screening tests for GHD.

• Macrocephaly: Defined as head circumference > 97th percentile for age and sex.

II. Puberty

• Normal Puberty - Girls:
  • First sign: Breast budding (thelarche), typically between 8-13 years.
  • Menarche: Usually occurs 2-2.5 years after thelarche, typically around Tanner stage 4. Minimal linear growth occurs after menarche.
  • Peak Height Velocity (PHV): Occurs around Tanner stage 3, before menarche.
  • Delayed Puberty: No breast development by age 13 or no menarche by age 15/16 (or within 3-5 years of thelarche).
  • Onset influenced by genetics (concordance with mother/sisters), ethnicity (earlier in Black girls), nutrition (earlier in obese girls, later in thin athletic girls).

• Normal Puberty - Boys:
  • First sign: Testicular enlargement (≥4 mL volume or >2.5 cm length), typically between 9-14 years.
  • Delayed Puberty: No testicular enlargement by age 14.
  • Peak height velocity occurs later than in girls.

• Precocious Puberty: Onset of pubertal signs before age 8 in girls or age 9 in boys.
  • Central Precocious Puberty: Early activation of HPG axis. Can be idiopathic or due to CNS pathology (more common to find pathology in boys and very young girls).

III. Thyroid Disorders

• Congenital Hypothyroidism (CH)
  • Most Common Cause: Thyroid dysgenesis (agenesis, ectopia, hypoplasia) - accounts for ~85% of cases. Usually sporadic.
  • Other Causes: Dyshormonogenesis (autosomal recessive), TSH deficiency (central), maternal antithyroid drugs (transient), iodine deficiency (endemic).
  • Epidemiology: Incidence ~1:3000-4000. Females > males. Less common in Black populations. Screening programs are vital (e.g., TSH, T4).
  • Clinical Manifestations (Early - often subtle/non-specific in first 4 weeks):
    • Prolonged jaundice, poor feeding, lethargy, constipation, hoarse cry, large anterior fontanelle, umbilical hernia.
    • Infant may look normal at birth.
    • Not typically irritability or excessive crying (more lethargy).
    • Not early closure of anterior fontanelle (it’s often delayed/large).
  • Clinical Manifestations (Later/Untreated - fully developed by 3-6 months):
    • Coarse facial features, large protruded tongue (macroglossia), myxedema (eyelids, external genitalia), short stature, broad hands/short fingers, developmental delay/intellectual disability, hypotonia (not hypertonia).
    • Head size may be normal or slightly smaller if untreated long-term, not always enlarged. Mouth often kept open. Hair coarse.
  • Diagnosis: Newborn screening (elevated TSH, low T4/FT4).
  • Treatment: Lifelong levothyroxine replacement. Early treatment is crucial to prevent irreversible intellectual disability.

• Central Hypothyroidism: Low T4 with normal or low TSH. Can be associated with cleft palate.

IV. Adrenal Disorders

• Congenital Adrenal Hyperplasia (CAH)
  • Most Common Form: 21-hydroxylase deficiency (accounts for >90% of cases).
    • Leads to cortisol and aldosterone deficiency, and androgen excess.
    • Salt-wasting form: Presents with hyponatremia, hyperkalemia, dehydration, adrenal crisis in early infancy.
    • Simple virilizing form: Androgen excess, normal aldosterone.
    • Non-classic (late-onset) form: Milder symptoms.
  • 11-β-hydroxylase deficiency: Causes hypertension (due to accumulation of 11-deoxycorticosterone, a mineralocorticoid), cortisol deficiency, androgen excess.
  • Ambiguous Genitalia: In 46,XX females due to androgen excess in utero.
  • Diagnosis: Elevated 17-hydroxyprogesterone (17-OHP) is key for 21-hydroxylase deficiency. Ultrasound may show uterus in virilized female.
  • Management of Adrenal Crisis: IV fluids (normal saline), stress doses of hydrocortisone, glucose. Fludrocortisone for mineralocorticoid replacement in salt-wasters (not acutely during stress dose hydrocortisone if that provides enough mineralocorticoid effect).

• Primary Adrenal Insufficiency (Addison’s Disease)
  • Lab Findings: Hyponatremia, hyperkalemia, hypoglycemia, elevated ACTH, positive antibodies to 21-hydroxylase (if autoimmune). Impaired (low) cortisol response to ACTH stimulation test.
  • Clinical Features: Weakness, fatigue, weight loss, skin hyperpigmentation (due to high ACTH), salt craving, postural hypotension.
  • Most common cause of adrenal insufficiency in children overall is withdrawal of long-term steroids.

• Secondary Adrenal Insufficiency: Due to pituitary ACTH deficiency. Low ACTH. Skin hyperpigmentation is absent.

• Adrenal Crisis (Infant): Severe dehydration, hyponatremia, hyperkalemia, metabolic acidosis, hypoglycemia, shock. Renin is high (due to hypovolemia/hyponatremia). Aldosterone is low (if primary).

V. Diabetes Mellitus & Hypoglycemia

• Type 1 Diabetes Mellitus (T1DM)
  • Most common cause of diabetes in pediatric age group is T1DM (antibody-mediated autoimmune destruction of beta cells).
  • Management: Insulin (long-acting and short-acting), blood glucose monitoring, HbA1c monitoring (target <7.5%), education on diet, exercise, hypoglycemia management.
  • Screening: For associated autoimmune conditions like thyroid disease and celiac disease.
  • Sports: Children with T1DM can participate in all sports, including competitive ones, with appropriate management.
  • This is a lifelong diagnosis.
  • Hypoglycemia Management (Conscious Child, BG 40 mg/dL): Give simple carbohydrates (e.g., cup of juice). Glucagon IM/SC if unconscious or unable to take oral.

• Neonatal Hypoglycemia
  • Causes: Infant of diabetic mother (hyperinsulinism), prematurity, SGA, LGA, perinatal asphyxia, sepsis, adrenal insufficiency, GHD, inborn errors of metabolism.
  • Congenital hypothyroidism does not directly cause neonatal hypoglycemia.
  • Blood sugar level <2.6 mmol/L (47 mg/dL) in first few hours, then <3.3 mmol/L (60 mg/dL). A level in a 2-hour old may be lower than in a 2-month old without being pathological if transient.

• Somogyi Phenomenon: Rebound hyperglycemia following an episode of hypoglycemia (often nocturnal, due to excessive insulin).

VI. Other Endocrine Points

• Obesity Consequences: Insulin resistance, Type 2 DM, hepatic steatosis, pseudotumor cerebri, cholelithiasis, sleep apnea, early menarche (not late).

• Disorders Associated with Hypertension: CAH (11-β-hydroxylase def.), Cushing’s, pheochromocytoma, renal artery stenosis.

• Growth Hormone Deficiency (GHD) in Neonates:
  • Clinical Features: Neonatal jaundice (prolonged), micropenis/microphallus, hypoglycemia, midline facial defects (e.g., cleft palate).
  • Birth weight is usually normal as fetal growth is largely GH-independent.

• Primary Adrenocortical Failure Laboratory Findings: Elevated ACTH, antibodies to 21-hydroxylase (if autoimmune), hyperkalemia, hyponatremia. A positive (i.e., significant rise in cortisol) high-dose ACTH stimulation test would rule out primary adrenal failure; a blunted or absent response indicates primary failure. Hypernatremia is not a feature.

• Turner Syndrome: Associated with congenital heart disease (CoA, bicuspid aortic valve), lymphedema, renal malformations, sensorineural hearing loss, ovarian dysgenesis leading to short stature and delayed/absent puberty. Growth velocity is usually decreased.

• Klinefelter Syndrome (47,XXY): Occurs only in males. Features include tall stature (not short), gynecomastia, small testes, infertility, delayed or incomplete pubertal development.

5. Neonatology

I. Assessment of the Newborn

• Gestational Age Definitions:
  • Preterm: < 37 weeks
  • Early Term: 37 0/7 - 38 6/7 weeks
  • Full Term: 39 0/7 - 40 6/7 weeks (sometimes up to 41 6/7 weeks)
  • Late Term: 41 0/7 - 41 6/7 weeks
  • Post-term: ≥ 42 weeks

• Birth Weight Classifications:
  • Low Birth Weight (LBW): < 2500 g
  • Very Low Birth Weight (VLBW): < 1500 g
  • Extremely Low Birth Weight (ELBW): < 1000 g
  • Small for Gestational Age (SGA): Birth weight < 10th percentile for GA.
  • Large for Gestational Age (LGA): Birth weight > 90th percentile for GA.

• Apgar Score:
  • Assesses newborn’s adaptation to extrauterine life at 1 and 5 minutes after birth (and serially if low).
  • Components (0, 1, or 2 points each): Appearance (color), Pulse (heart rate), Grimace (reflex irritability), Activity (muscle tone), Respiration.
  • Acrocyanosis (blue hands/feet, pink body) scores 1 for Appearance.
  • It is a score for all newborns, not just term infants.
  • Capillary refill time is not part of the Apgar score.
  • It is used to guide resuscitation efforts, but decisions about initial resuscitation steps are made before the 1-minute score.
  • It has limited predictive value for long-term outcomes like epilepsy or IQ.
  • Crying is not a must for score 2 in breathing; regular, strong cry or good respiratory effort scores 2.

• Physical Examination:
  • Initial assessment: Done immediately after birth by a pediatrician or skilled personnel, especially if risk factors are present.
  • Full comprehensive examination: Should be done within 24 hours of delivery.
  • Normal cardiac exam at delivery room does not rule out congenital heart disease.
  • Normal findings can include: Mongolian spots, breast engorgement, pulsating umbilical cord, palpable posterior fontanelle, erythema toxicum, vaginal bleeding/discharge in females.
  • Abnormal findings can include: Bifid uvula (may be isolated or syndromic), craniotabes (can be normal in premies or associated with rickets/OI), Wormian bones (can be normal or syndromic), single umbilical artery (associated with anomalies). Epstein pearls (small white cysts on palate) and vernix caseosa are normal. Milia are normal.
  • Bulging fontanelle is always abnormal.
  • One umbilical artery is abnormal and warrants investigation for other anomalies.

• Thermoregulation:
  • Newborns, especially preterms, are at high risk for hypothermia.
  • Management for preterm (e.g., 28-weeker): Dry immediately, wrap, place in a radiant warmer or incubator, use plastic bag or warming pads.
  • High humidity can decrease insensible water losses in incubators.

II. Neonatal Jaundice (Hyperbilirubinemia)

• Physiological Jaundice:
  • Appears after 24 hours of life.
  • Total serum bilirubin (TSB) rises < 5 mg/dL/day.
  • Peak TSB usually < 12-15 mg/dL in term infants.
  • Predominantly indirect (unconjugated) bilirubin. Direct bilirubin < 2 mg/dL or <20% of TSB.
  • Resolves by 1-2 weeks in term infants (may be longer in preterms).
  • Mechanisms: Increased bilirubin load (shorter RBC lifespan, higher hematocrit), decreased hepatic uptake, impaired conjugation (immature UGT enzyme), increased enterohepatic circulation.
  • Exaggerated by: Prematurity, breastfeeding (due to relative dehydration/caloric restriction initially), low caloric intake, dehydration.

• Pathological Jaundice:
  • Jaundice appearing within the first 24 hours of life.
  • TSB rising > 5 mg/dL/day or >0.2-0.5 mg/hr.
  • TSB > 15 mg/dL in term infants (thresholds vary with age and risk factors).
  • Direct (conjugated) bilirubin > 2 mg/dL or >20% of TSB.
  • Jaundice persisting > 2 weeks in term infants or > 3 weeks in preterm infants.
  • Signs of illness (lethargy, poor feeding, etc.).
  • Most common cause of jaundice in the first 24 hours of life: Hemolysis (e.g., ABO/Rh incompatibility, G6PD deficiency, spherocytosis).

• Breastfeeding Jaundice (Early Onset):
  • Occurs in the first week of life.
  • Due to insufficient breast milk intake, leading to dehydration, decreased caloric intake, and increased enterohepatic circulation.
  • Prevented/managed by frequent and effective nursing.

• Breast Milk Jaundice (Late Onset):
  • Occurs after the first week of life, may persist for several weeks/months.
  • Due to substances in breast milk (e.g., β-glucuronidase, pregnanediol) that inhibit bilirubin conjugation or increase enterohepatic circulation.
  • Infant is usually thriving, stools normal.
  • Predominantly indirect bilirubin.
  • High bilirubin levels in breast milk jaundice are generally not associated with a high risk of neurotoxicity (kernicterus) if managed appropriately.
  • Usually resolves even if breastfeeding is continued; temporary interruption of breastfeeding is rarely needed.

• Causes of Unconjugated Hyperbilirubinemia (Prolonged): Breast milk jaundice, hypothyroidism, Crigler-Najjar syndrome, Gilbert syndrome, pyloric stenosis, ongoing hemolysis. Urinary tract infection (UTI) can cause conjugated or mixed hyperbilirubinemia, not typically isolated prolonged unconjugated.

• Causes of Conjugated (Direct) Hyperbilirubinemia: Biliary atresia, neonatal hepatitis (idiopathic, infectious - TORCH), choledochal cyst, alpha-1 antitrypsin deficiency, galactosemia, tyrosinemia, cystic fibrosis, Alagille syndrome. Gilbert syndrome and hypothyroidism cause unconjugated hyperbilirubinemia.

• Management of Hyperbilirubinemia:
  • Phototherapy: Converts unconjugated bilirubin to water-soluble isomers.
    • Side effects: Skin rash, dehydration (increased insensible water loss), loose stools, bronze baby syndrome (if direct hyperbilirubinemia present), corneal ulcers (if eyes not protected). Infection is not a direct side effect.
  • Exchange Transfusion: Indicated for very high TSB levels or signs of acute bilirubin encephalopathy. Factors considered: TSB level, age of neonate (hours/days), presence of hemolysis, risk factors (acidosis, sepsis, prematurity). Type of feeding (breast vs. formula) is not a primary factor in the decision for exchange transfusion itself, though it influences jaundice development.

• Kernicterus (Bilirubin Encephalopathy): Neurotoxic effects of unconjugated bilirubin deposition in the brain.

• General Points:
  • Visual estimation of jaundice is inaccurate. TSB/TcB measurement is needed.
  • Normal physical exam does not exclude pathological jaundice.
  • Breastfed infants are generally more likely to have hyperbilirubinemia than formula-fed infants.
  • Water supplementation is not recommended for breastfed babies to prevent jaundice.
  • IVIG may be used as adjunctive therapy for isoimmune hemolytic jaundice (e.g., ABO/Rh).

III. Respiratory Disorders

• Respiratory Distress Syndrome (RDS):
  • Primary cause: Surfactant deficiency in premature infants.
  • Most common respiratory disorder of premature infants.
  • Clinical signs: Tachypnea, grunting, intercostal/subcostal retractions, nasal flaring, cyanosis. Usually appears within minutes to hours of birth. Breath sounds may be normal or decreased.
  • CXR: Diffuse symmetrical reticulogranular (ground glass) appearance, decreased lung inflation, air bronchograms.
  • Course: Signs typically peak within 2-3 days (not 5-7 days), then improve with treatment. Worsening after 72 hours suggests complications.
  • Apnea can be a sign of RDS, but its presence suggests significant disease, not mild.
  • Treatment: Supportive ventilation (CPAP, mechanical ventilation), exogenous surfactant administration. Antenatal corticosteroids to mother reduce incidence/severity.

• Transient Tachypnea of the Newborn (TTN):
  • Caused by delayed absorption/clearance of fetal lung fluid.
  • More common in term/near-term infants, especially after C-section or precipitous delivery.
  • Onset: Usually within hours of birth.
  • Clinical signs: Tachypnea, mild retractions, occasional grunting.
  • Course: Usually self-limiting, resolves within 24-72 hours. Rarely lasts beyond 48 hours.
  • CXR: Perihilar streaking, fluid in fissures, mild hyperinflation. Air bronchogram is not a characteristic feature.
  • Treatment: Supportive (oxygen if needed). Surfactant is not indicated.

• Meconium Aspiration Syndrome (MAS):
  • Occurs in term or post-term infants who pass meconium in utero and aspirate it.
  • Meconium-stained amniotic fluid is a sign of potential fetal distress/intrauterine hypoxemia.
  • Clinical signs: Respiratory distress, tachypnea, cyanosis.
  • CXR: Coarse, patchy infiltrates, hyperinflation, atelectasis. Air bronchogram is not a primary feature.
  • Complications: Pneumothorax, persistent pulmonary hypertension of the newborn (PPHN).
  • Meconium is sterile, but can cause chemical pneumonitis and predispose to secondary bacterial infection.

• Grunting Mechanism: Exhalation against a partially closed glottis to increase end-expiratory pressure and prevent alveolar collapse (auto-PEEP).

IV. Neonatal Sepsis

• Early Onset Sepsis (EOS): Occurs within the first 72 hours of life.

• Most Common Pathogens (EOS): Group B Streptococcus (GBS), Escherichia coli. Listeria monocytogenes. Coagulase-negative staphylococci (CoNS) are more common in late-onset sepsis, especially in VLBW infants with indwelling catheters, and are not a typical cause of EOS in term infants.

• Empirical Treatment (EOS): Ampicillin (covers GBS, Listeria) AND Gentamicin (covers gram-negatives like E. coli).

• Gram-negative sepsis with meningitis should be treated for at least 2-3 weeks. Neonatal sepsis has high mortality.

• Most common cause of neonatal sepsis at term: Group B Streptococcus (S. agalactiae).

V. Other Neonatal Conditions

• Prematurity Complications: RDS, apnea of prematurity, osteopenia of prematurity, necrotizing enterocolitis (NEC), intraventricular hemorrhage (IVH), retinopathy of prematurity (ROP), patent ductus arteriosus, sepsis, neurodevelopmental delay, ADHD, lower visual acuity, failure to thrive. Hypothyroidism is screened for in all newborns; prematurity itself isn’t a direct cause but premies are more vulnerable to thyroid dysfunction.

• Infant of Diabetic Mother (IDM):
  • Complications: Macrosomia, hypoglycemia (due to fetal hyperinsulinemia), polycythemia, hyperbilirubinemia, RDS (delayed lung maturation), cardiac anomalies (hypertrophic cardiomyopathy, VSD, TGA), hypocalcemia, hypomagnesemia.
  • Risk of congenital anomalies is reduced if maternal diabetes is well-controlled pre-conception and during pregnancy.
  • Associated with polyhydramnios, not oligohydramnios.

• Postmature Infants (>42 weeks):
  • Complications: Meconium aspiration, PPHN, hypoglycemia (due to depleted glycogen stores), polycythemia, birth trauma (if macrosomic), dysmaturity syndrome (peeling skin, long nails, decreased vernix/subcutaneous fat).
  • Often have chronic intrauterine hypoxia.

• Osteopenia of Prematurity: Diagnosed with labs including serum alkaline phosphatase and phosphorus.

• Apnea of Prematurity: Caffeine is used to decrease apnea rate by stimulating respiratory drive.

• Cephalohematoma: Subperiosteal collection of blood, does not cross suture lines, confined to one cranial bone. Appears hours to days after birth. Can be a risk factor for jaundice. May calcify. Resolves in weeks to months (not 1 day). Observation is main management.

• Caput Succedaneum: Edema of scalp soft tissue, crosses suture lines, present at birth, resolves in days.

• Fluid and Electrolyte Therapy:
  • Sodium is generally not added to IV fluids on the first day of life.
  • Premature infants have higher insensible water losses and need more fluids per kg.
  • Maintenance fluid for newborns: Glucose 10% (D10W) or D10 with electrolytes (e.g., D10 ¼ NS) after the first day. Glucose 5% is not standard maintenance for neonates.
  • Fluids should be restricted if a hemodynamically significant PDA is present.
  • Potassium should be added to IV fluids only after adequate urine output is established.

• Neonatal Resuscitation:
  • A skilled person should be present at every delivery.
  • First 30 seconds are for initial steps: Warm, dry, stimulate, position airway, suction if needed.
  • Positive pressure ventilation (PPV) if apneic, gasping, or HR <100 bpm. Chest compressions if HR <60 bpm despite adequate PPV.
  • Epinephrine (not Atropine) is the drug for bradycardia unresponsive to ventilation/compressions.
  • All newborns are typically placed under a radiant warmer initially for assessment and care; pulse and RR are checked.

• Infant Botulism: Prevented by not giving honey to infants <1 year old.

• Single Umbilical Artery: Associated with increased risk of congenital anomalies (renal, cardiac).

6. Neurology

I. Developmental Milestones & Assessment

• General Principles: Development proceeds in a cephalocaudal and proximodistal manner. There’s a range for achieving milestones.

• Gross Motor:
  • Head lift (prone): Present at birth (briefly). Full head support (no head lag when pulled to sit): 4 months.
  • Rolls over (prone to supine): 4-6 months. (Supine to prone usually later, 5-7 months).
  • Sits with pelvic support: ~6 months. Sits without support: 6-8 months.
  • Crawls/Creeps: 8-10 months.
  • Pulls to stand: 9-10 months.
  • Cruises (walks holding onto furniture): 10-12 months.
  • Walks with one hand held: 12-15 months. Walks alone well (unassisted): 12-15 months (range 9-17 months).
  • Runs stiffly: 18 months. Runs well: 2 years.
  • Goes upstairs with alternation of feet: 30 months (2.5 years).
  • Hops on one foot: 4 years.
  • Skips: 5 years.

• Fine Motor:
  • Tracks visually human faces: Present at birth/early weeks. Tracks 180 degrees: 2 months.
  • Hands predominantly closed at birth, open by 2-3 months.
  • Reaches for objects: 3-4 months.
  • Grasps objects (palmar grasp): 3-5 months.
  • Transfers objects hand to hand: 5-6 months.
  • Immature pincer grasp (thumb and index finger): 8-10 months. Neat pincer grasp: 10-12 months.
  • Puts objects in mouth: 4-6 months.
  • Releases toy on demand: ~10-12 months.
  • Scribbles: 15-18 months.
  • Draws vertical line: 1.5-2 years. Horizontal line: 2-2.5 years.
  • Copies a circle: 3 years.
  • Copies a cross: 4 years. Copies a square: 4-4.5 years.
  • Copies a triangle: 5 years.
  • Cuts picture with scissors: 4 years.
  • Ties shoelaces: 5-6 years.

• Language:
  • Reacts to sounds: Birth.
  • Coos (vowel sounds): 2-3 months.
  • Laughs: 4 months.
  • Babbles (consonant-vowel chains): 6-9 months.
  • “Mama/Dada” (non-specific): 8-10 months. “Mama/Dada” (specific): 10-12 months.
  • Understands “no”: 9-10 months.
  • Speaks 1-3 words (other than mama/dada): 12 months.
  • Speaks 6 words: ~15-18 months. 10 single words: ~18 months.
  • Points to body parts: 18-24 months.
  • 2-word sentences: 18-24 months.
  • Speaks ~50 words: 2 years.
  • Knows full name: 30 months (2.5 years). Knows age: 3 years.
  • Uses pronouns (me, I, you): 2.5-3 years. Refers to self by “I”: ~3 years (not 4).
  • Tells stories: 4 years.

• Social/Cognitive:
  • Social smile: 2 months (range 1-3 months). Delayed social smile can indicate cognitive problems.
  • Enjoys looking at mirror: ~6 months.
  • Stranger anxiety: 6-9 months.
  • Peek-a-boo: 9-10 months. Waves bye-bye: 9-10 months.
  • Points to desired object: 12-15 months.
  • Knows self age and sex: Typically by 3-4 years. Not at 18 months.
  • Parallel play: 2-3 years.
  • Knows heavier of two objects: 5 years.

• Vision:
  • Visual fixation: Present at birth.
  • Ability to follow a bright target: Present since birth.
  • Visual acuity reaches 20/20: By 3-5 years (not 6 months).
  • Ability to distinguish colors: Develops over first few months; some color vision at birth, good by 5-6 months. Internet sources vary, but 3 months is plausible for significant development.

• Developmental Delay:
  • Global Developmental Delay (GDD): Significant delay (≥2 SD below mean) in two or more developmental domains (gross motor, fine motor, language, social/personal, cognitive).
  • Most common identifiable cause of GDD is genetic/chromosomal. Many cases remain idiopathic.
  • Chromosomal analysis is indicated even without dysmorphic features if GDD is present.
  • Blind infant: Prone to social delay (due to lack of visual cues for bonding/interaction) and gross motor delay (less motivation for exploration).
  • Deaf child: Primarily expected to have language delay.

• Corrected Age for Prematurity: Use corrected age for developmental assessment until 2 years of age. (e.g., 7-month-old born at 28 weeks GA = 12 weeks or ~3 months premature; corrected age = 7m - 3m = 4 months).

II. Seizures & Epilepsy

• Febrile Seizures (FS)
  • Simple FS: Generalized (usually tonic-clonic), duration < 15 minutes, does not recur within 24 hours, no focal features, child neurologically normal before/after.
  • Complex FS: Duration > 15 minutes, focal features, and/or recurs within 24 hours.
  • Risk Factors for Recurrence: Age <18m at first FS, family history of FS, fever <39°C at onset of FS, short duration between fever onset and seizure.
  • Risk of Subsequent Epilepsy:
    • Simple FS: Slightly increased risk (2-5%) compared to general population (~1%).
    • Complex FS, neurodevelopmental abnormalities, family history of epilepsy increase risk significantly. A simple FS does not increase risk by 10 folds.
  • Management:
    • Acute: ABCs, abort seizure if >5 min (e.g., rectal diazepam). Antipyretics for comfort.
    • No need for routine antiepileptic drug (AED) prophylaxis.
    • Lumbar Puncture (LP): Strongly consider if <12 months with first FS. Consider if 12-18 months. If >18 months, based on clinical suspicion of meningitis. Clearly indicated in younger age groups.

• Neonatal Seizures
  • Subtle seizures are common (e.g., lip smacking, eye deviation, bicycling movements). Change in vital signs can help diagnose.
  • Treatment of choice: Phenobarbital.
  • Can carry poor prognosis for neurodevelopment.
  • Causes: Hypoxic-ischemic encephalopathy (HIE), intracranial hemorrhage, infection (meningitis), metabolic (hypoglycemia, hypocalcemia, hypomagnesemia, hyponatremia, hypernatremia), inborn errors, drug withdrawal. Hypokalemia is not a major cause.
  • Generalized tonic-clonic seizures are less common than subtle or focal clonic in neonates.

• Absence Seizures (Petit Mal)
  • Brief episodes of staring, loss of awareness, +/- automatisms. No postictal state.
  • EEG: Generalized 3 Hz spike-and-wave discharges.
  • Drug of choice: Ethosuximide (if only absence) or Valproic acid (if coexisting GTCs).

• Partial (Focal) Seizures
  • Simple Partial: Consciousness preserved. Symptoms depend on affected brain area.
  • Complex Partial: Consciousness impaired. Often with automatisms. Temporal lobe origin common.
  • Characteristic of partial complex seizures: Change in level of consciousness. Epileptic activity often arises from temporal or frontal lobe. Patient usually does not remember the event.
  • Focal seizure with impaired awareness (complex partial): e.g., child with sudden right arm clonic movement and lack of response.

• Infantile Spasms (West Syndrome)
  • Sudden, brief, symmetrical contractions (flexor, extensor, or mixed). Occur in clusters, often on awakening.
  • Onset: Typically 3-12 months.
  • EEG: Hypsarrhythmia (chaotic, high-voltage activity).
  • Often associated with underlying brain disorders (e.g., tuberous sclerosis).
  • Treatment: ACTH, Vigabatrin. Prognosis is often poor for development.
  • Vagal nerve stimulation is not first-line treatment.

• Lennox-Gastaut Syndrome
  • Severe childhood epilepsy syndrome. Multiple seizure types (tonic, atonic, atypical absence), developmental delay, characteristic slow spike-wave EEG.
  • Least likely to respond to medical treatment among common epilepsy syndromes.

• Rolandic Epilepsy (Benign Rolandic Epilepsy)
  • Common childhood focal epilepsy. Seizures typically nocturnal, involving face/mouth. Good prognosis.

• Status Epilepticus
  • Seizure lasting >5 minutes or recurrent seizures without recovery of consciousness.
  • Associated with ~5% mortality rate.
  • Can cause focal neurological deficits.
  • Intubation is not always required, only if airway/breathing compromised.

• Gelastic Seizures: Recurrent attacks of laughter, often associated with hypothalamic hamartomas.

• Differentiation of Seizures vs. Non-Epileptic Paroxysmal Events (e.g., breath-holding spells): Detailed history and physical exam are key. EEG is useful if epilepsy suspected. Breath-holding spells can involve uprolling of eyes, cyanosis, and myoclonic jerks when frustrated/angry/crying.

III. Neurological Conditions

• Cerebral Palsy (CP)
  • Non-progressive disorder of movement and posture due to an insult to the developing brain. Neurological status (the underlying brain lesion) does not deteriorate, but clinical manifestations can change.
  • Risk Factors: Prematurity, low birth weight, intrauterine infections, perinatal asphyxia, multiple gestation. Consanguinity is not a direct risk factor unless it leads to a genetic condition predisposing to CP.
  • Most common type: Spastic CP. Diplegic CP is common in preterms.
  • Choreoathetotic CP: Often related to bilirubin encephalopathy (kernicterus) damaging basal ganglia.
  • Mental retardation (intellectual disability) is common but not universal. More common in quadriplegic CP.
  • The majority of children with CP are born at term, although prematurity is a major risk factor.
  • Vaccination is not contraindicated. Pertussis vaccine is given as per schedule.
  • Language skills do not typically deteriorate with time in CP. Deafness does not worsen.
  • Tetraplegic CP generally carries a worse prognosis.
  • Epilepsy occurs in about one-third of cases.

• Acute Ataxia (Child): If wide-gait, consider post-infectious cerebellitis, intoxication, tumor. Brain MRI is an important investigation.

• Primitive Reflexes:
  • Assess integrity of brainstem and basal ganglia. Usually symmetrical.
  • Asymmetry suggests focal brain or peripheral nerve injury.
  • Most disappear by 4-6 months due to maturation of the frontal lobe.
  • Persistence beyond expected age or re-emergence can indicate neurological dysfunction.
  • All primitive reflexes should disappear by 1 year (not 2 years), except protective reflexes.
  • Examples: Moro (disappears 5-6m), Palmar grasp (2-3m), Asymmetric Tonic Neck (6-7m), Rooting (1-2m).
  • Parachute reflex: Appears ~8-9 months and persists for life.

• Cerebral Hypotonia: Can be indicated by other brain abnormalities, fasciculations, ophthalmoplegia. Hyperreflexia suggests UMN lesion/spasticity, not hypotonia.

• Electrolyte Abnormalities Causing Seizures: Hyponatremia, hypernatremia, hypoglycemia, hypocalcemia, hypomagnesemia. Hypokalemia is not a common direct cause of seizures.

• Neurological Examination:
  • Vibration sense: Detected at birth.
  • Babinski reflex (upgoing toe): Normal up to 1-2 years.
  • Non-sustained clonus (a few beats): Can be normal up to 2 months.
  • Receptive language is usually more mature than expressive language.
  • Indirect light reflex: Present at birth.

IV. Miscellaneous Neurology

• Valproic Acid Side Effects: Alopecia, thrombocytopenia, elevated liver enzymes, drowsiness, weight gain (not weight loss).

• Tuberous Sclerosis Complex: Ash leaf spots, subependymal nodules/calcification, infantile spasms (West syndrome), developmental delay.

• Sturge-Weber Syndrome: Port-wine stain (facial nevus flammeus, typically V1 distribution), seizures, glaucoma, developmental delay.

• Breath-Holding Spells: Paroxysmal non-epileptic events in young children, often triggered by anger/frustration (cyanotic type) or pain/fright (pallid type). Can involve LOC, cyanosis, brief posturing or clonic jerks. EEG is normal.

7. Infectious Diseases

I. Vaccinations

• Live Attenuated Vaccines: MMR (Measles, Mumps, Rubella), OPV (Oral Polio Vaccine), BCG (Bacillus Calmette-Guérin), Varicella, Rotavirus. Hepatitis A vaccine is an inactivated vaccine.

• Contraindications to DTaP/DTwP:
  • Absolute for subsequent doses: Anaphylaxis to a previous dose or component; encephalopathy within 7 days of a previous dose of DTP/DTaP not attributable to another cause.
  • Precautions (defer or consider risk/benefit): Fever ≥40.5°C within 48h; collapse or shock-like state (hypotonic-hyporesponsive episode) within 48h; persistent, inconsolable crying ≥3 hours within 48h; seizure with or without fever within 3 days.

• Vaccine Not Given at 6 Months (Jordan National Schedule example): Hepatitis A Vaccine (HAV) (typically given at 12m and 18m). DTaP, OPV, Hib, PCV, IPV are typically given at 6 months in many schedules.

• Newborn of Hepatitis B Positive Mother: Administer Hepatitis B vaccine AND Hepatitis B Immune Globulin (HBIG) immediately (within 12 hours of birth) at different sites. Complete the full 3-dose vaccine series (e.g., 0, 1-2, 6 months).

• Rotavirus Vaccine:
  • Live oral vaccine.
  • Contraindicated for children older than 8 months (first dose not to be given after 15 weeks, series completed by 8 months due to increased risk of intussusception).
  • Effective in decreasing severe diarrhea and dehydration.
  • Transmitted person-to-person.
  • Not contraindicated in healthy siblings of patients with leukemia (but consult specialist if sibling is actively immunosuppressed).
  • Not contraindicated in pregnancy (it’s an infant vaccine).

• MMR Vaccine:
  • Live attenuated.
  • Previous febrile seizure is not a contraindication.
  • Encephalopathy is a very rare adverse effect, but generally considered safe.
  • Varicella can be given at the same time as MMR or separated by at least 4 weeks.

• OPV (Oral Polio Vaccine):
  • Live attenuated. Safe in newborns. Recommended in outbreaks.
  • Can cause Vaccine-Associated Paralytic Poliomyelitis (VAPP) in rare cases (incidence much less than 1/1000).
  • IPV (Inactivated Polio Vaccine) is not contraindicated after 18 years; it’s preferred in many countries to avoid VAPP. OPV is generally not given to adults in non-endemic areas.
  • OPV is generally superior to IPV in inducing gut immunity and controlling community spread, but IPV has no risk of VAPP. “Less risk of paralysis” is true for IPV (no VAPP), but OPV is more effective at stopping person-to-person spread.

• Hepatitis A Vaccine: Killed (inactivated) virus vaccine. Not contraindicated after 12 years (recommended for susceptible individuals).

• Pneumococcal Vaccine:
  • Conjugated vaccine (PCV) is indicated for infants <2 years and prevents nasopharyngeal carriage.
  • Polysaccharide vaccine (PPSV23) is poorly immunogenic in children <2 years.
  • Not absolutely contraindicated in pregnancy (PPSV23 may be given if high risk). PCV is contraindicated <6 weeks.
  • Pneumococcal vaccine is not contraindicated after 5 years; PCV and/or PPSV23 are recommended for high-risk older children/adults.

• Hib Vaccine (Haemophilus influenzae type b):
  • Conjugate vaccine. Composed of PRP polysaccharide conjugated to a carrier protein (not outer membrane protein).
  • Not indicated/needed after 5 years of age in healthy children.
  • Contraindicated before 6 weeks of age.
  • Prevents Hib carriage.

• Varicella Zoster Vaccine: Live attenuated. Generally safe to give to a child with ITP who has been off IVIG for at least 3-11 months (duration varies by IVIG dose, 9 months is a reasonable specific figure provided).

• Tetanus Vaccine: Toxoid. Neonatal tetanus can be prevented by maternal immunization. Not contraindicated in immunocompromised individuals (may have suboptimal response). Disease does not confer immunity; vaccine needed after recovery. Tetanus vaccine content (amount of toxoid) differs for infants/children (DTaP/DT) vs. adults/older children (Tdap/Td). Composed of inactivated tetanus toxoid.

• Diphtheria Vaccine: Toxoid. Adult formulation (Td) contains a smaller amount of diphtheria toxoid than pediatric (DTaP/DT). Not a killed whole cell vaccine.

• BCG Vaccine: Live attenuated.

• General Contraindication to Vaccines: Severe anaphylactic reaction to a previous dose or to a vaccine component.

• Vaccination in Immunocompromised Contacts: Live vaccines (e.g., MMR, Varicella, OPV) are generally safe to give to close contacts (e.g., sibling) of immunocompromised individuals (e.g., child with leukemia on chemotherapy), as herd immunity is beneficial. OPV is an exception in some guidelines due to shedding.

II. Specific Infections

• Varicella (Chickenpox):
  • Caused by Varicella-Zoster Virus (VZV). Characterized by latency and reactivation as Herpes Zoster (shingles).
  • Outcome is worse in newborns, immunocompromised individuals, and adults compared to healthy children. It is not milder in adults.
  • Rash typically appears first on the trunk or face, then spreads.
  • Vaccine effective post-exposure if given within 3-5 days.
  • Transmission in pregnancy can lead to congenital varicella syndrome or neonatal varicella.
  • Acyclovir is effective for severe infections/complications like encephalitis.

• Diphtheria:
  • Immunized individuals can still carry the organism.
  • Antitoxin should be given as soon as possible in suspected cases, without waiting for culture confirmation.
  • Vaccine is a toxoid.
  • Only toxigenic strains of Corynebacterium diphtheriae cause disease.
  • Diphtheria toxin production is phage-induced. Myocarditis is a serious complication.

• Poliomyelitis:
  • Neurogical deficit is limited to motor neurons (anterior horn cells).
  • Little cross-immunity between the three serotypes (Type 1, 2, 3).
  • Humans are the only natural host.
  • Adults have a higher rate of paralysis than children.
  • The overwhelming majority of infections are asymptomatic. Paralysis is usually asymmetrical.
  • Chronic carrier state is rare but described in immunodeficient individuals.
  • Polio is not transmitted from cats to man.

• Hepatitis A:
  • Rarely acquired by blood transfusion. Most contagious in pre-icteric phase.
  • Infection is more likely to be severe in adults; often asymptomatic or mild in young children.
  • Immune globulin (IG) is effective for post-exposure prophylaxis in exposed household contacts.
  • Disease is acquired from humans (fecal-oral).

• Acute Bacterial Meningitis:
  • Poor Prognostic Factors: Seizure occurring late in course (e.g., on 7th day), focal neurological deficit, Gram-negative organism, development of brain abscess, papilledema at presentation. Convulsions in the first four days can affect prognosis.
  • Empiric Therapy: Should include a third-generation cephalosporin (e.g., ceftriaxone) and vancomycin.
  • Dexamethasone: Should be administered before or with the first dose of antibiotics (within 4 hours of antibiotics) in suspected bacterial meningitis (primarily for Hib and pneumococcal) to reduce neurological sequelae.
  • Most common in the first five years of life.

• Meningococcal Infection (Neisseria meningitidis):
  • Gram-negative diplococcus.
  • Immunity is type-specific (serogroup-specific).
  • Nasopharyngeal carriage rate is ~5-10% in general population, can be higher.
  • Prophylaxis for close household contacts is necessary. (Rifampin, ceftriaxone, or ciprofloxacin). Ceftriaxone is safe for prophylaxis in pregnant women.
  • More severe in patients with complement deficiency.
  • Meningococcemia (sepsis) generally has a worse outcome than isolated meningitis.
  • Treatment: Penicillin or third-generation cephalosporin (e.g., ceftriaxone). Vancomycin is not the drug of choice unless penicillin resistance is high and specific.
  • Low platelet count is a bad prognostic sign.

• Pneumococcal Disease (Streptococcus pneumoniae):
  • Most common cause of occult bacteremia in children in Jordan (and many places).
  • Only a few serotypes cause the majority of invasive disease.
  • Vancomycin is used for penicillin-resistant pneumococcal meningitis.
  • Most common cause of acute bacterial meningitis in all age groups after the newborn period.
  • Contacts of pneumococcal meningitis generally do not need antibiotic prophylaxis (unlike meningococcal or Hib).

• Pertussis (Whooping Cough):
  • Bacteremia rarely occurs.
  • Vaccine indicated for pregnant women (Tdap) to protect newborns via passive immunity.
  • Acellular pertussis vaccine is generally less effective for long-term protection than whole-cell vaccine but has fewer side effects.
  • Contraindicated in patients with progressive CNS disease.
  • Vaccinating contacts of premature infants is indicated.
  • Highly contagious. Most cases are symptomatic, though can be atypical/milder in adolescents/adults. Patients have lymphocytosis.
  • Azithromycin is the preferred drug, especially in infants <1 month.

• Tetanus:
  • Caused by toxin produced by Clostridium tetani.
  • Disease is toxin-mediated; bacteremia does not occur.
  • Patients recovering from tetanus should receive the tetanus vaccine as natural infection does not reliably confer immunity.
  • Patients who have received ≥3 doses of tetanus toxoid generally do not require TIG for clean, minor wounds; Td/Tdap booster if >10 years since last dose.
  • Anti-tetanus antibodies (IgG) do cross the placenta, providing passive immunity to the neonate if the mother is immunized.

• Botulism (Infant): Can be prevented by not giving honey to infants under 1 year of age.

• Mumps:
  • Transmitted by droplets. Aseptic meningitis is the most common complication.
  • Orchitis is more common in post-pubertal males than pre-pubertal boys.
  • Mumps vaccine is not contraindicated in thalassemia major (unless other specific contraindications exist).
  • Mumps vaccine can be given to adults if susceptible.
  • Antiviral therapy is of no value.

• Rubella:
  • Only one serotype. Vaccine can be given to adults.
  • Primary maternal infection, especially in the first trimester, poses the highest risk for Congenital Rubella Syndrome (CRS).
  • Rubella is often subclinical or mildly apparent, not almost always clinically apparent.
  • A second dose of rubella vaccine (as part of MMR) is advised for durable immunity.
  • Maximal risk to fetus is in the first two months of pregnancy. Vaccine is contraindicated in patients on high-dose steroids.
  • Congenital Rubella Syndrome is not typically characterized by macrocephaly with intracranial calcifications (that’s more suggestive of congenital toxoplasmosis or CMV). CRS features: cataracts, heart defects (PDA, PS), sensorineural deafness, microcephaly, blueberry muffin rash.
  • Rash typically starts on the face and spreads caudally.

• Measles:
  • Prodrome (cough, coryza, conjunctivitis - “3 Cs”) is essential. Highly contagious via respiratory route.
  • Vaccine is not contraindicated after 25 years if susceptible.
  • Vaccine can be administered to patients on low-dose/maintenance inhaled steroids; high-dose systemic steroids are a contraindication.
  • Infection is most serious in malnourished and very young children.
  • Vitamin A supplementation is indicated in all patients in developing countries or with risk factors, as it reduces morbidity/mortality.
  • Immunity following natural disease is lifelong.
  • Encephalitis occurs in ~1/1000 cases.
  • Contagious by airborne route (not just contact).

• Salmonella Infections:
  • S. typhi (typhoid fever) is primarily human-restricted; acquisition from dogs is unlikely.
  • S. enteritidis can be transmitted from contaminated eggs and poultry.
  • Infants develop bacteremia more frequently than older children.
  • Antibiotic treatment of non-typhoidal Salmonella gastroenteritis is generally not necessary in immunocompetent older children/adults (can prolong carriage).
  • Invasive Salmonella infections (e.g., osteomyelitis) are more common in patients with sickle cell disease.

• Post-Exposure Prophylaxis (PEP):
  • Hepatitis A: Hepatitis A vaccine and/or Immune Globulin (IG).
  • Tetanus: Tetanus toxoid vaccine and/or Tetanus Immune Globulin (TIG), depending on wound type and immunization history.
  • Chickenpox: Varicella vaccine (if given within 3-5 days) or Varicella-Zoster Immune Globulin (VZIG).
  • Measles: Measles vaccine (if given within 72 hours) or Immune Globulin (IG).
  • Diphtheria: Diphtheria toxoid vaccine and prophylactic antibiotics (e.g., erythromycin). Antidiphtheric antiserum (antitoxin) is for treatment, not PEP.

• Isolation Precautions:
  • Pertussis: Droplet.
  • Pulmonary TB: Airborne.
  • Rotavirus gastroenteritis: Contact (+ Standard).
  • Measles: Airborne.
  • Pneumococcal bacteremia: Standard precautions (not typically requiring specific isolation unless meningitis with resistant organism or other factors).

8. Nephrology & Fluids/Electrolytes

Dehydration

• Assessment:
  • Mild (3-5%): Slightly decreased intake/output, thirsty, normal exam.
  • Moderate (6-9%): Lethargic/irritable, sunken eyes/fontanelle, decreased tears, dry mucous membranes, decreased skin turgor, prolonged capillary refill (2-3s), tachycardia, decreased urine output.
  • Severe (≥10%): Apathetic/comatose, very sunken eyes/fontanelle, no tears, parched membranes, tenting skin turgor, very prolonged capillary refill (>3s), tachycardia/bradycardia (late), hypotension (late), minimal/no urine output. Profound signs indicate severe dehydration.
  • Earliest sign often tachycardia or decreased urine output. Prolonged capillary refill is reliable sign.

• Types:
  • Isotonic (most common): Na 130-150 mEq/L.
  • Hypotonic: Na <130 mEq/L. Risk of cerebral edema during rehydration.
  • Hypertonic: Na >150 mEq/L. Doughy skin, irritability/lethargy, increased thirst. Risk of cerebral hemorrhage (due to dehydration) and cerebral edema/seizures if rehydrated too quickly. Correct deficit slowly over 48 hours.

• Fluid Calculation (Holliday-Segar Maintenance):
  • 100 mL/kg/day for first 10 kg
  • 50 mL/kg/day for next 10 kg (11-20 kg)
  • 20 mL/kg/day for weight >20 kg
  • Example: 12 kg child = (100x10) + (50x2) = 1000 + 100 = 1100 mL/day.
  • Example: 20 kg child = (100x10) + (50x10) = 1000 + 500 = 1500 mL/day.
  • Example: 25 kg child = 1500 + (20x5) = 1500 + 100 = 1600 mL/day (slide says 1625?).

• Fluid Management:
  • Oral Rehydration Therapy (ORT): Preferred for mild-moderate dehydration. Use commercial ORS. Give small frequent amounts. Continue breastfeeding/feeding.
  • Intravenous Fluids (IVF): For severe dehydration, shock, inability to take ORT.
    • Bolus: 20 mL/kg Normal Saline (0.9% NaCl) over 15-30 min (repeat as needed for shock). 7kg child needs 140ml bolus. 15kg child needs 300ml bolus.
    • Deficit Replacement: Calculate % dehydration x weight (kg) = deficit (L). Replace deficit + maintenance over 24h (usually half in first 8h, rest over 16h) OR over 48h for hypernatremia.
    • Fluid Choice: Maintenance usually D5 0.45% NaCl or D5 0.2% NaCl (+ 20 mEq/L KCl once voiding). Deficit often replaced with 0.45% or 0.9% NaCl. Initial resuscitation always with isotonic fluid (0.9% NS or LR). 10% dextrose water not appropriate for resuscitation/deficit. D5W is maintenance fluid for first 24h in newborn without complications.

Urinary Tract Infection (UTI)

• Incidence: High in first year, esp. uncircumcised males and females. Prolonged jaundice can be presentation in infants. Constipation is risk factor.

• Diagnosis:
  • Symptoms: Infants (fever, irritability, vomiting, poor feeding, jaundice), Older children (dysuria, frequency, urgency, incontinence, abdominal/flank pain, fever).
  • Urinalysis (Dipstick): Nitrite specific (most Gram-negatives convert nitrate->nitrite), but not sensitive (needs urine in bladder ~4h). Leukocyte esterase (LE) sensitive for pyuria, but not specific for UTI. Nitrite alone highly sensitive is wrong. LE+Nitrite most suggestive. Protein/blood non-specific.
  • Microscopy: Pyuria (>5 WBCs/hpf). Bacteriuria.
  • Culture (Gold Standard): Method matters. Suprapubic aspirate (any growth significant). Catheter specimen (>10^3 - 10^5 CFU/mL significant, depends on source). Clean catch midstream (>10^5 CFU/mL significant). Bag urine unreliable (high contamination rate).

• Imaging:
  • Renal Ultrasound (RUS): Done after first febrile UTI in infants/young children to look for structural abnormalities, hydronephrosis.
  • Voiding Cystourethrogram (VCUG/MCUG): To diagnose Vesicoureteral Reflux (VUR). Indications debated, often done after 2nd febrile UTI or first UTI with abnormal RUS/atypical organism/poor response. Not routine after first UTI. Can detect posterior urethral valves.
  • DMSA Scan: Detects acute pyelonephritis and renal scarring (gold standard for scarring). Usually done 4-6 months after UTI to assess for scarring. Should NOT be done in first month to assess scarring.

• Management: Antibiotics (7-14 days for pyelonephritis). Infants <2-3 months usually admitted for IV antibiotics. Older children with pyelonephritis may be treated outpatient if well-appearing/reliable. Treat asymptomatic bacteriuria ONLY in pregnancy (or before urologic procedure).

• Vesicoureteral Reflux (VUR): Retrograde flow of urine from bladder to ureters/kidneys. Graded I-V. Lower grades often resolve spontaneously (e.g., Grade II often resolves in 5 yrs). Higher grades associated with renal scarring/recurrent pyelonephritis. Prophylactic antibiotics controversial.

Electrolyte Abnormalities

• Hyponatremia (Na < 135):
  • Hypovolemic: Renal losses (diuretics, adrenal insufficiency, RTA) or Extrarenal losses (GI - diarrhea/vomiting, sweat - CF, third spacing). Urine Na low (<20) in extrarenal, high (>20) in renal. Adrenal insufficiency causes hypovolemic hyponatremia with high urine Na. Gastroenteritis causes hypovolemic hyponatremia with low urine Na.
  • Euvolemic: SIADH (high urine Na, high urine osm), psychogenic polydipsia (low urine osm), hypothyroidism.
  • Hypervolemic: CHF, nephrotic syndrome, cirrhosis (low urine Na).
  • Cerebral Salt Wasting: Hyponatremia with volume depletion and high urine sodium, usually after CNS injury/surgery.
  • Management: Treat underlying cause. Fluid restriction for SIADH. Normal saline for hypovolemic. Hypertonic saline (3%) for severe symptomatic hyponatremia (seizures) - correct slowly. Oral salt supplements/steroids not primary tx for SIADH.

• Hypernatremia (Na > 145): Due to water loss > salt loss (DI, fever, burns, diarrhea) or excessive salt intake. See Dehydration section.

• Hypokalemia (K < 3.5): Causes: GI losses, diuretics, RTA types 1&2, alkalosis, insulin, beta-agonists. Manifestations: Weakness, fatigue, constipation, paralytic ileus, arrhythmias, ECG changes (U waves, flat T waves). Confusion less typical.

• Hyperkalemia (K > 5.5): Causes: Renal failure, adrenal insufficiency (Addison’s, CAH), acidosis, cell lysis (rhabdo, TLS), K-sparing diuretics, ACEi/ARBs. Manifestations: Weakness, paralysis, arrhythmias, ECG changes (peaked T waves, wide QRS). Management: Calcium gluconate (stabilize membrane), Insulin+glucose, Kayexalate, Bicarbonate, Albuterol, dialysis.

• Addison’s disease (Primary Adrenal Insufficiency): Causes hypokalemia, hyperkalemia, hyponatremia.

• SIADH: Hyponatremia, euvolemic, high urine Na (>40), high urine osmolality (>100), low serum osmolality. Often due to CNS or pulmonary disorders.

Other Nephrology Topics

• Nephrotic Syndrome: Characterized by heavy proteinuria (>3.5g/day or >40mg/m2/hr), hypoalbuminemia (<2.5 g/dL), edema, hyperlipidemia. Minimal Change Disease (MCD) most common type in children (responds well to steroids).
  • Features: Edema (scrotal, periorbital, generalized), ascites. Increased bleeding tendency is NOT typical (hypercoagulable state due to loss of antithrombin III - low levels expected).
  • Complications: Spontaneous Bacterial Peritonitis (SBP) - often pneumococcal, thrombosis, infections (loss of IgG), AKI (due to hypovolemia or diuretics).
  • Management: Steroids (prednisone) primary treatment for MCD (induces remission in >90%). Salt restriction, diuretics (carefully - risk of hypovolemia). Albumin infusion + Lasix for severe edema/anasarca. ACEi/ARBs for persistent proteinuria. Renal biopsy usually reserved for atypical features (age <1 or >12, hypertension, hematuria, low C3, steroid resistance). Angiotensin converting enzyme inhibitor is NOT acute management.

• Renal Tubular Acidosis (RTA): Metabolic acidosis with normal anion gap. Associated with FTT, rickets, nephrocalcinosis. Causes hypokalemia (Types 1 & 2) or hyperkalemia (Type 4).

• Glomerular Filtration Rate (GFR): Reaches adult levels (around 120 mL/min/1.73m2) by approximately 2 years of age.

• Asymptomatic Bacteriuria: Presence of bacteria in urine without symptoms. Generally benign in children, does not require treatment or increase risk of scarring. Can be normal finding in neurogenic bladder.

9. Miscellaneous

I. Kawasaki Disease (KD)

• Definition: An acute febrile vasculitis, predominantly affecting medium-sized arteries, of unknown etiology. It is the leading cause of acquired heart disease in children in most developed countries.

• Diagnostic Criteria:
  • Fever persisting for ≥ 5 days (essential criterion).
  • Plus at least 4 of the 5 following principal clinical features:
    1. Bilateral non-purulent conjunctival injection.
    2. Oral mucous membrane changes: Erythema and cracking of lips (cracked lips), strawberry tongue, diffuse erythema of oropharyngeal mucosa.
    3. Extremity changes:
       • Acute: Erythema and edema of hands and feet (tender swollen hands/feet).
       • Subacute: Periungual desquamation (peeling of skin of fingers/toes).
    4. Polymorphous rash (maculopapular, scarlatiniform, or erythema multiforme-like).
    5. Cervical lymphadenopathy (usually unilateral, ≥1.5 cm in diameter).
  • Elevated liver enzymes are common but not part of the diagnostic criteria. Subcutaneous nodules are not a feature of KD.

• Complications:
  • Coronary artery aneurysms (CAA): Occur in ~20-25% of untreated children. IVIG treatment reduces this risk to <5%. It does not occur in the majority of patients if treated.

• Laboratory Findings:
  • Elevated ESR, CRP.
  • Leukocytosis with neutrophilia.
  • Normocytic anemia.
  • Thrombocytosis (high platelet count) typically develops in the second to third week of illness. Thrombocytopenia can occur early in severe cases but is not typical for the course of KD.

• Treatment:
  • Intravenous Immunoglobulin (IVIG): High dose (2 g/kg) over 10-12 hours.
  • Aspirin: High dose initially for anti-inflammatory effect, then low dose for antiplatelet effect.

• Etiology: Presumed infectious trigger in genetically predisposed individuals (viral infection is a leading hypothesis but not definitively proven).

II. Malnutrition

• General Principles:
  • Severely malnourished patients require gradual nutritional rehabilitation, not aggressive full caloric supplementation immediately, to avoid refeeding syndrome.
  • During rehabilitation, serum levels of electrolytes (calcium, magnesium, phosphorus, potassium) must be carefully monitored.
  • Vitamin D and iron deficiency are commonly encountered.

• Marasmus:
  • Primarily due to severe overall caloric (energy) deficiency.
  • Most common form of primary protein-energy malnutrition (PEM) globally.
  • Clinical features: Severe wasting (loss of subcutaneous fat and muscle atrophy), emaciated appearance, “old man” facies, alert and irritable. Skin is dry, hair thin and sparse.
  • Pitting edema is characteristically absent.

• Kwashiorkor:
  • Primarily due to severe protein deficiency, often with adequate or near-adequate caloric intake (e.g., starchy diet).
  • Clinical features: Pitting edema (starting in lower limbs), dermatosis (flaky paint), hair changes (dyspigmented, sparse), hepatomegaly (fatty liver), apathy, anorexia.

III. Vitamin Deficiencies & Excesses

• Vitamin A Deficiency: Night blindness, xerophthalmia, Bitot’s spots, keratomalacia, increased susceptibility to infections. Alopecia is not a primary sign (more related to biotin, zinc, iron deficiency).

• Vitamin C Deficiency (Scurvy): Gingivitis, bleeding gums, perifollicular hemorrhage, corkscrew hairs, impaired wound healing.

• Vitamin D Deficiency (Rickets/Osteomalacia): Defective bone mineralization.

• Vitamin E Deficiency: Hemolytic anemia (especially in premature infants), neurological deficits.

• Vitamin K Deficiency: Impaired coagulation, bleeding tendency (e.g., hemorrhagic disease of the newborn).

• Vitamin B12 Deficiency: Megaloblastic anemia, neurological symptoms (paresthesias, ataxia, memory loss).

• Water-Soluble Vitamins: Vitamin C, B-complex vitamins (B1 Thiamine, B2 Riboflavin, B3 Niacin, B5 Pantothenic acid, B6 Pyridoxine, B7 Biotin, B9 Folate, B12 Cobalamin).

• Fat-Soluble Vitamins: Vitamins A, D, E, K. Vitamin K is fat-soluble.

• Terminal Ileum Resection: Can lead to Vitamin B12 deficiency (as B12 is absorbed in the terminal ileum).

IV. Child Abuse

• Most Frequent Physical Abusers of Children: Parents (mother alone or both parents together are often cited).

• Most Common Clinical Manifestation of Physical Child Abuse: Bruises.

V. Anorexia Nervosa

• Complications: Osteoporosis, hypotension, bradycardia (not tachycardia), arrhythmias, constipation, amenorrhea, lanugo hair.

VI. Acrodermatitis Enteropathica

• Inherited (autosomal recessive) or acquired disorder of zinc absorption/metabolism.

• Caused by severe zinc deficiency.

• Clinical Features: Characteristic triad of acral/periorificial dermatitis, alopecia, and diarrhea. Failure to thrive is usually present, not absent.

VII. Aspirin Uses in Pediatrics

• Kawasaki Disease (anti-inflammatory and antiplatelet).

• Acute Rheumatic Fever (anti-inflammatory, though NSAIDs often preferred now).

• Not for routine antipyresis in children (Reye’s syndrome risk).

• Not for thrombocytosis (it’s antiplatelet, used to prevent thrombosis, not treat high platelet count itself).

• Not for congenital nephrotic syndrome.

VIII. Obesity Complications

• Insulin resistance, Type 2 Diabetes Mellitus.

• Hypertension, dyslipidemia.

• Elevated liver enzymes (Non-alcoholic fatty liver disease - NAFLD).

• Sleep apnea.

• Pseudotumor cerebri.

• Increased risk of certain malignancies compared to the normal population (not lower risk).

IX. Sudden Unconsciousness in an Infant

• Initial Management (First thing to do): Assess and ensure Airway, Breathing, Circulation (ABCs). If airway compromise is suspected (e.g., noisy breathing, drooling), suctioning the nose and clearing the airway would be a priority within ABCs. Checking blood sugar is important but secondary to ensuring a patent airway and adequate breathing/circulation.