Master Pediatrics
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Core Concepts
Pediatrics covers growth, development, and health from birth through adolescence. Key areas include well-child visits, vaccinations, developmental milestones, common childhood illnesses, and emergent conditions. Growth is monitored via standardized growth charts (weight, height/length, head circumference), while development is assessed using age-appropriate milestones. Prevention is central, with universal newborn screening and adherence to the CDC's immunization schedule being paramount. Common etiologies of illness often differ from adults (e.g., viral causes predominant in respiratory infections, genetic syndromes, congenital anomalies). Family-centered care and consideration of psychosocial factors are crucial.
Clinical Presentation
- Neonatal Jaundice: Yellow skin/sclera, direct hyperbilirubinemia is always pathologic.
- Bronchiolitis (RSV): <2 years, viral prodrome, wheezing, tachypnea, retractions.
- Croup (Laryngotracheobronchitis): Barking cough, inspiratory stridor, hoarseness, often viral.
- Asthma: Recurrent wheezing, cough (worse at night/with activity), shortness of breath, chest tightness.
- Febrile Seizures: 6 months - 5 years, generalized tonic-clonic seizure with fever, no CNS infection.
- Pyloric Stenosis: 2-8 weeks old, non-bilious projectile vomiting after feeds, often hungry post-emesis.
- Intussusception: 3 months - 3 years, sudden onset intermittent colicky abdominal pain, "currant jelly" stools, sausage-shaped abdominal mass.
- Hirschsprung Disease: Failure to pass meconium in first 24-48 hours, chronic constipation, abdominal distension.
- Appendicitis: Periumbilical pain migrating to RLQ, anorexia, nausea, vomiting, fever.
- UTI: Infants: fever without source, poor feeding, irritability. Older children: dysuria, frequency, urgency, enuresis.
- Kawasaki Disease: Fever >5 days + 4/5 criteria: conjunctivitis, rash, adenopathy, strawberry tongue/oral changes, hand/foot changes.
- Henoch-Schönlein Purpura (HSP): Palpable purpura (buttocks/legs), arthritis, abdominal pain, renal involvement (hematuria/proteinuria).
- Minimal Change Disease (Nephrotic Syndrome): Periorbital edema, ascites, generalized edema, frothy urine.
- Post-streptococcal Glomerulonephritis (PSGN): 1-3 weeks post strep infection, gross hematuria, edema, hypertension.
- Meningitis: Fever, lethargy, irritability, poor feeding, bulging fontanelle (infants); headache, stiff neck, photophobia (older children).
Diagnosis (Gold Standard)
Growth/developmental assessment uses CDC growth charts and standardized screening tools (e.g., ASQ-3). Newborn screening varies by state but typically includes metabolic disorders (e.g., PKU, congenital hypothyroidism, galactosemia), hemoglobinopathies (e.g., sickle cell disease), and cystic fibrosis. Specific gold standards include:
Pyloric Stenosis: Abdominal Ultrasound (target sign, elongated/thickened pylorus).
Intussusception: Abdominal Ultrasound (target/pseudokidney sign), Air Enema (diagnostic and therapeutic).
Hirschsprung Disease: Rectal Biopsy (absence of ganglion cells in submucosal and myenteric plexuses).
UTI: Urine Culture (from catheterized sample in infants/young children, midstream clean catch in older children).
Meningitis: Lumbar Puncture with CSF analysis.
Cystic Fibrosis: Sweat Chloride Test.
Lead Poisoning: Serum Lead Level.
Management (First Line)
Vaccinations: Adhere to ACIP/CDC schedule.
Bronchiolitis: Supportive care (hydration, nasal suctioning). Bronchodilators, steroids, and antibiotics are NOT recommended.
Croup: Dexamethasone (single oral dose) for mild-moderate; Racemic Epinephrine for moderate-severe stridor at rest.
Asthma: Albuterol (SABA) for acute exacerbations; Inhaled Corticosteroids (ICS) for long-term control.
Febrile Seizures: Reassurance, antipyretics (no proven benefit in preventing recurrence).
Pyloric Stenosis: Fluid/electrolyte resuscitation, then surgical pyloromyotomy.
Intussusception: Air enema (reduces 75-90%); surgical reduction if enema fails or peritonitis present.
Hirschsprung Disease: Surgical resection of aganglionic segment.
Appendicitis: Surgical appendectomy.
UTI: Empiric oral or IV antibiotics (e.g., Ceftriaxone, Cefixime, Bactrim) based on age/severity, for 7-14 days.
Kawasaki Disease: IVIG + High-dose Aspirin.
HSP: Supportive care. Steroids for severe abdominal pain or joint symptoms. Renal follow-up.
Minimal Change Disease: Oral corticosteroids (e.g., Prednisone).
PSGN: Supportive care (fluid restriction, diuretics for edema, antihypertensives for HTN).
Meningitis: IV antibiotics (Ceftriaxone + Vancomycin, add Ampicillin for neonates); Dexamethasone for H. flu type B.
Anaphylaxis: IM Epinephrine.
Exam Red Flags
- Fever without a source in infants <3 months: Always work up for sepsis (LP, UA, blood culture).
- Abnormal Red Reflex: Suspect retinoblastoma or congenital cataracts.
- Lack of Social Smile by 2 months, Rolling over by 6 months, Walking by 18 months, First words by 15 months: Developmental delay.
- Non-bilious projectile vomiting in a young infant: Pyloric stenosis.
- Currant jelly stools + intermittent colicky pain: Intussusception.
- Barking cough + inspiratory stridor: Croup (acute onset, worse at night).
- Drooling + Tripoding + Acute stridor/dysphagia: Epiglottitis (rare but life-threatening).
- Inconsistent history for injury, multiple fractures in different stages of healing, metaphyseal fractures, retinal hemorrhages: Child abuse.
- Severe unilateral scrotal pain + absent cremasteric reflex: Testicular torsion (surgical emergency).
- Sudden onset limp + hip pain: Rule out septic arthritis (medical emergency), SCFE, Legg-Calve-Perthes, transient synovitis.
- Fatigue, Pallor, Pica, Developmental Delay: Iron deficiency anemia.
Sample Practice Questions
A 6-month-old infant is brought to the pediatrician by his parents with a 3-day history of runny nose and cough, which has now progressed to difficulty breathing and poor feeding. On examination, the infant is tachypneic (respiratory rate 65/min) with prominent nasal flaring, subcostal retractions, and expiratory wheezing and crackles heard bilaterally. Oxygen saturation is 90% on room air. His temperature is 38.0°C (100.4°F). Rapid viral panel is positive for Respiratory Syncytial Virus (RSV). Which of the following is the most appropriate management for this patient?
A 6-year-old boy with a known history of asthma presents to the emergency department with acute onset of severe shortness of breath, wheezing, and coughing. He reports he has been feeling worse for the past few hours and is now struggling to speak in full sentences. His vital signs are: HR 120 bpm, RR 35 breaths/min, O2 saturation 89% on room air. Physical examination reveals significant accessory muscle use, diffuse inspiratory and expiratory wheezing, and decreased air entry. What is the most appropriate initial pharmacologic intervention for this patient's acute exacerbation?
A 10-year-old boy presents with a 2-week history of fatigue, dark-colored urine, and swelling around his eyes and ankles. He recently recovered from a 'strep throat' infection, which was treated with a 5-day course of amoxicillin. On examination, his blood pressure is 145/95 mmHg, and he has periorbital and pedal edema. Urinalysis shows proteinuria (3+), hematuria (red blood cell casts present), and specific gravity 1.025. Serum creatinine is 1.5 mg/dL (elevated for age), and C3 complement levels are low. What is the most likely diagnosis?
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