Fever of unknown origin (FUO) is defined as an elevated body temperature higher than 100 o F for a minimum 8 days without a clear source. Although fever is a common problem in children and can be easily managed, FUO needs special attention. This article delineates characteristic etiologies of FUO in children and core management strategies. Diagnosing pediatric FUO is a challenge to the physicians since the spectrum of the origin is broad ranging from oncologic to iatrogenic. The underlying reason may be any abnormal representation of a common disease or life-threatening.

FUO differs from fever without source (FWS) on the grounds of duration. FWS progresses to FUO if no etiology is detected even after one week of fever. COMMON CAUSES OF PEDIATRIC FUO FUO in children can have a large degree of underlying etiologies. Hence diagnosis is often complex. Infectious origin: Bacterial: Abscess,…