Pediatric Infectious Diseases and Immunology
What to master
Know vaccination schedules and contraindications, including live vaccine precautions in immunodeficiency. Understand fever without a source in infants-age-based workup and the threshold for lumbar puncture. Master common infections by age: neonatal sepsis (group B streptococcus, E. coli), toddler pneumonia (viruses), school-age Mycoplasma. Know TORCH infections and their classic features. Understand primary immunodeficiency warning signs: recurrent severe infections, failure to thrive, family history, and unusual organisms. Know HIV in children-vertical transmission, prevention, and diagnosis by PCR in infants.
Concepts that recur
Meningitis requires immediate antibiotics; do not delay for imaging if the child is unstable. Kawasaki disease is an infectious-immunologic mimic-consider it in prolonged fever. Tuberculosis in children is often paucibacillary; use contact history and IGRA/tuberculin testing. Malaria should be excluded in febrile children returning from endemic areas. Antibiotic stewardship questions ask when not to prescribe-viral upper respiratory infections are the classic.
Traps
Examiners test neonatal fever-any fever in a neonate warrants full sepsis evaluation and admission. Another trap is vaccine timing with live vaccines and immunodeficiency. Beware interpreting tuberculin skin tests in BCG-vaccinated children-IGRA may help.
Rule of thumb
Any fever in an infant under 28 days is a sepsis evaluation until proven otherwise. For recurrent infections, ask about the type of organism-encapsulated bacteria suggest antibody or complement defects; fungi and atypical organisms suggest T-cell defects.