FEVER OF UNKNOWN ORIGIN: CLINICAL CHARACTERISTICS AND ETIOLOGICAL SPECTRUM

Abstract

Objective: This study aimed to provide an overview of the etiological distribution, clinical features, and laboratory findings among patients with classic fever of unknown origin (FUO) admitted to the University Clinic for Infectious Diseases and Febrile Conditions in Skopje.

Materials and Methods: All participants underwent a comprehensive medical history review, physical examination, and predetermined laboratory investigations. The final diagnosis was established using specific diagnostic procedures guided by potential diagnostic clues (PDCs). After diagnosis, patients were categorized into infectious and non-infectious FUO groups.

Results: The analysis included 47 participants, with a mean age of 57 years, the majority of whom were male. Fever lasted an average of 30 days, with a median temperature of 39 °C. Infections accounted for 53.2% of cases, followed by inflammatory non-infectious diseases (25.5%), malignancies, and other miscellaneous conditions (10.6%). The most frequent symptoms were myalgia, arthralgia, fever, sweating, and malaise. On physical examination, hepatosplenomegaly, heart murmurs, joint swelling, and skin rashes were the predominant findings. Significant laboratory abnormalities included elevated ferritin and procalcitonin levels across groups.

Conclusion: Specific variations in clinical presentation and laboratory findings may help facilitate a more rapid differential diagnosis of classic FUO.