Fever of unknown origin (peds)

Background

• Prolonged fever of unknown origin without identified cause generally has favorable prognosis.

Clinical Features

• Original definition
  • Fever >38.3 C on several occasions
  • Lasting for at least 3 weeks
  • No clear diagnosis after 1 week inpatient workup
• Newer definition - "Prolonged fever" with:
  • 3 outpatient visits without identifying a cause or
  • 3 inpatient days without identifying a cause or
  • 1 week of “intelligent and invasive” ambulatory investigation

Differential Diagnosis

• Infection
  • Bacterial
    • Adenitis
    • Endocarditis
    • Mastoiditis
    • Occult abscess
    • Pyelonephritis
    • Sinusitis
    • Tb
  • Viral
    • CMV
    • Hep A,B, C
    • Mono
  • Chlamydial
    • Lymphogranuloma venereum
    • Psittacosis
  • Mycoplasmal
  • Fungal
    • Blastomycosis
    • Cysticercosis
    • Histoplasmosis
    • Rickettsial
      • Q fever
      • Rocky Mt
    • Parasitic
      • Malaria
      • Toxo
• Non-infectious Inflammatory
  • JRA
  • LSE
  • Regional enteritis
  • Rheumatic fever
  • Ulcerative colitis
  • Vasculitis
• Malignancy
  • Leukemia
  • Lymphoma
  • Neuroblastoma
  • Wilm's tumor
• Drug Induced
  • Antibiotics
  • Anticonvulsants
  • Anti TB
  • Procainamide
  • Quinidine
  • Serum sickness
• Misc
  • AIDS
  • CNS
  • Environmental
  • Factitious
  • Familial dysautonomia
  • Kawasaki
  • PE
  • Serial infections
  • Thyrotoxicosis

Diagnosis

• Clinical (preliminary) diagnosis

Management

• Treat underlying cause (once identified)
• Empiric treatment generally not recommended

Disposition

• Frequently admitted for workup

See Also

• Pediatric fever of uncertain source