Approach to a Child with Fever

The approach to a febrile child consists of a good medical history, a targeted physical examination, and the judicious use of laboratory tests. System-specific symptoms and signs give a clue to the site of infection. Nonspecific symptoms like poor feeding, irritability, and lethargy indicate serious illness. In fever of <7 days, without a focus, the management depends upon the age. All febrile neonates should be hospitalized, investigated for sepsis, and started on empiric antibiotic therapy. Ill-appearing children and those with complex comorbidities or immunodeficiency are at a greater risk of serious bacterial infection (SBI), regardless of their age and should be investigated accordingly. For well-appearing febrile children between 1 and 3 months of age, a complete blood count (CBC), C reactive protein, and urine microscopy to look for evidence of SBI are recommended. If the decision is made to not do blood tests, reliable follow-up is of utmost importance. Those aged 3 months to 36 months, with fever <39 °C (102.2 °F) can be managed symptomatically with parental education on the red flags. Those with fever >39 °C (102.2 °F) are at risk for bacterial infection. In fully immunized children, occult urinary tract infection (UTI) is the most common cause. In areas endemic for dengue fever, dengue NS1 antigen and baseline CBC are useful in the first 4 days. Fever for >7 days without a diagnosis on initial evaluation is called fever of unknown origin (FUO) and could be due to infectious or noninfectious causes. In children, unusual presentations of common infections are the most common cause. The evaluation of these children should proceed in a stepwise manner preferably after hospitalization. Diagnostic tests are best guided by ongoing assessment for historical, physical, and basic laboratory clues.