From Fever of Undetermined Origin to Miliary Tuberculosis

Although most episodes of fever in paediatric patients return to normal within a couple of days, some patients show prolonged fever. When a temperature of more than 38.0°C lasts longer than 8 days without a clear source, the term Fever of Unknown Origin (FUO) is used (James W. Antoon, Nicholas M. Potisek, Jacob A. Lohr. Pediatric Fever of Unknown Origin. Pediatr Rev 2015; 36(9): 380–391). In high-income countries, FUO is related to underlying infections with viral or bacterial microorganisms in more than 50% of affected children. In low- and middle-income countries (LMIC), tuberculosis (TB) is a common infectious cause of FUO, and must always be considered as a potential differential diagnosis (Chusid M. Pediatric Clinics of North America 2017; 64 (1): 205–230).