Fever of Unknown Origin

Fevers of unknown origin (FUO) remain a diagnostic dilemma. The differential remains broad with etiology most commonly including infectious, autoimmune, and malignant related. A significant portion of adolescents with FUO may never have an identifiable etiology found. However, the prognosis of FUO without determined etiology and in the absence of red flag symptoms is overall reassuring.

Automated summary

Fevers of unknown origin (FUO) present a diagnostic challenge, with a wide range of potential causes including infectious, autoimmune, and malignant. Some adolescents with FUO may never have an identifiable etiology, but the prognosis is generally favorable in the absence of red flag symptoms.