Fever of Unknown Origin: a clinical approach

Abstract

Fever of unknown origin remains a common challenge in clinical practice.  A systematic approach to working up a patient includes a thorough history and physical exam.  The most likely cause can then be assigned to one of four broad categories: infection, inflammatory, malignancy, and miscellaneous.  These broader classes help guide initial diagnostic tests and avoid unnecessary, more invasive procedures.  Despite a thorough workup, as many as 30% of all FUO cases are never solved.  The current evidence points to a favourable prognosis for these cases and, thus, empiric treatment is generally not recommended.  This review aims to help future physicians understand the broad differential diagnosis of FUO pathogenesis of diabetic retinopathy and neuropathy, and provides a summary of the current literature and evidence–based recommendations for working up FUO.