Pediatric Infectious Diseases and Immunology
Core concepts
Understand fever evaluation by age: neonates with fever require full sepsis workup and empiric antibiotics; older children can be stratified by appearance and source. Know common infections: otitis media, pharyngitis (group A Streptococcus, when to treat), pneumonia (viral vs bacterial), meningitis (age-specific organisms), and urinary tract infection. Understand vaccine-preventable diseases and the immunization schedule, plus antibiotic stewardship. Recognize immunodeficiency red flags (recurrent severe infections, failure to thrive, family history) and the difference between primary and secondary immunodeficiency. Know HIV basics (vertical transmission, testing, prophylaxis) and tuberculosis (screening, latent vs active). Understand fever of unknown origin approach and Kawasaki disease as a mimic.
Traps
- Treating a neonate with fever as low risk - full workup and antibiotics are required.
- Missing meningitis because of a normal-looking child early in the course.
- Overusing antibiotics for viral illness.
- Missing primary immunodeficiency because infections are attributed to daycare exposure.
- Forgetting that immunization status affects the differential.
Worked example / rule of thumb
A 21-day-old with fever 38.2°C: obtain blood, urine, and CSF cultures, start empiric antibiotics covering group B Streptococcus, Escherichia coli, and Listeria, and admit. Rule of thumb: fever in a neonate (<28 days) = full sepsis workup and empiric antibiotics; recurrent severe infections = evaluate for immunodeficiency.