FEVER OF UNKNOWN ORIGIN: DIAGNOSTIC CHALLENGES FROM INFECTIOUS DISEASES PERSPECTIVE
Keywords:
Fever of unknown origin, potential diagnostic clues, infectious etiologyAbstract
Aim: To evaluate the diagnostic value of potentially diagnostic clues in distinguishing infectious from non-infectious causes of fever of unknown origin (FUO).
Material and methods: We conducted a retrospective–prospective, single-center study involving patients older than 14 years who met the criteria for classical FUO. Medical history, physical examination findings, and a standardized laboratory panel were collected for all participants. After the final diagnosis, patients were divided into infectious and non-infectious groups. Demographic characteristics, clinical features, and laboratory results were compared between groups.
Results: A total of 79 patients were included, with a mean age of 50.6±17.1 years (range 15–77). Males represented 61.1% of cases and were more common in the infectious FUO group (p=0.016), with this group showing higher febrile peak (p<0.001). Infectious diseases accounted for 51.9% of cases. In this group, notable clinical findings included fatigue (sensitivity 63.4%), fever (sensitivity 75.6%), heart murmur (positive likelihood ratio [+LR] 4.8), and splenomegaly (+LR 2.23). Key features of the non-infectious group were arthralgia (+LR 3.96), neck pain (+LR 3.49), joint swelling (+LR 6.44), and rash (+LR 3.49). Elevated procalcitonin (p=0.006), ALT (p=0.04), AST (p=0.02), and globulin levels (p=0.016) was noted in infectious FUO, while ferritin (p=0.047) and LDH (p=0.03) were higher in the non-infectious group.
Conclusions: The identified differences in diagnostic variables between infectious and noninfectious causes of classical FUO may assist initial etiologic differentiation and improve utilization of the diagnostic process.
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