THE ETIOLOGY OF FEVER OF UNKNOWN ORIGIN IN ADULTS

Abstract

Background: Fever of unknown origin (FUO) is a complex clinical problem. The underlying causes can vary depending on disease patterns and the diagnostic capability of healthcare facilities. Understanding the causes of FUO is essential to improve the diagnostic process.

Objective: To describe the spectrum of diseases that cause FUO in adult patients.

Methods: A prospective cross-sectional study was conducted on 143 patients aged ≥18 years diagnosed with FUO from July 2022 to April 2024 at Hospital for Tropical Diseases.

Result: Among the 143 FUO patients, infectious diseases were the most common cause, accounting for 47.5% (68/143), followed by smalignancy, autoimmune diseases, and miscellaneous causes with rates of 15.4%, 15.4%, and 13.3%, respectively. In 8.4% (12/143) of cases, the diagnosis was unclear. Tuberculosis (14.7%) and melioidosis (5.6%) were the most common infectious diseases. Lymphoma (6.3%) and systemic lupus erythematosus (7.7%) were the most common conditions in the malignancy and autoimmune disease groups, respectively.

Conclusion: Infectious diseases were the most common cause of FUO, in which tuberculosis and melioidosis being the two most prevalent diseases. Malignancy, autoimmune diseases, and miscellaneous causes each accounted for comparable proportions.

Keywords: fever of unknown origin; tuberculosis; melioidosis