Pediatric fever

Diagnosis

• Age-Based Diagnostic Stratification:
  • Neonate (< 28 days): Full sepsis workup is mandatory regardless of clinical appearance.
    • Labs: CBC w/ differential, blood culture, urinalysis (UA) + urine culture (catheterized specimen).
    • Lumbar Puncture (LP): CSF analysis (cell count, protein, glucose) + CSF culture + CSF PCR (if HSV suspected).
    • Imaging: CXR only if respiratory symptoms are present.
  • Infants (29–60/90 days): Risk stratification (e.g., AAP 2021 guidelines).
    • Well-appearing: Perform screening tests (CBC, UA + culture, inflammatory markers: CRP, procalcitonin).
    • If inflammatory markers are elevated or UA is abnormal: LP, blood/urine cultures, and admission for empiric antibiotics.
    • If all screening tests are normal: Can consider close outpatient monitoring without antibiotics, or LP + empiric IM Ceftriaxone with 24-hour follow-up.
  • Children (3 months to 3 years): Focus on identifying a source.
    • If no source identified: UA + urine culture is the most high-yield screening test (especially in uncircumcised males <1 year, circumcised males <6 months, females <2 years). c
    • CBC/Blood culture: Generally reserved for unimmunized/partially immunized children, or temperature ≥ 39°C.
• Key Lab Findings:
  • CSF: Pleocytosis (↑ WBCs), ↑ protein, and ↓ glucose suggest bacterial meningitis.
  • UA: (+) Leukocyte esterase, nitrites, or >5 WBCs/hpf suggests UTI.