Comparison Of Diagnostic Subgroup Survivals Of Patients Who Admitted For Fever Of Unknown Etiology Evaluation: Long-Term Results Of Single-Centre, Prospective Study

Abstract

Introduction: Fever of unknown origin (FUO) is one of the most challenging clinical situations. Although several studies have shown a relatively benign course of patients that remain undiagnosed, long-term outcoms of patients with a certain diagnosis are still non-established. To describe the follow-up results of patients investigated for FUO, with a certain diagnosis. Materials and Methods: Data from patients admitted to the inpatient dinics of Hacettepe University Hospital inpatients Department of Internal Medicine with the complaint of FUO were collected prospectively from March 2015 to September 2017. Patients with an uncertain diagnosis after all diagnostic procedures were excluded. Patients were divided into 3 main subgroups: rheumatologic, infectious and malignant groups. We compared Kaplan-Meier curves for all diagnosis-to-death time frames with the standart log-rank test. p< 0.05 was considered as statistically significant. Results: A total of 106 patients were included, 58 (55%) of them were female. Median age was 48 (18-81) years. Patients were also divided into three subgroups: rheumatologic (RHE) (n= 49, 46.2%), infectious (INF) (n= 28, 26.4%) and malignant (MLG) (n= 29, 27.4%) causes; adult-onset Still's disease (n= 20; 41% of), tuberculosis (n= 9; 32%) and lymphoma (n= 19; 66%) were the most common diagnosis among the groups, respectively. While there was no survival difference between the rheumatologic and infectious group, both of these groups had better survival than the malignant group (ROM-INF p= 0.13; ROM-MLG p= 0.001; INF-MLG p= 0.022). Among the female patients, there was only a significant survival difference between the rheumatologic and malignant group (ROM-INF p= 0.15; ROM-MLG p= 0.007; INF-MLG p= 0.42). Conclusion: Among the patients evaluated for FUO, survival rate was lower in patients who had a malignant diagnosis. Despite having lost its statistical significance after stratification for gender, mortality rate of the infectious group was followed the malignant group. Early diagnosis and treatment of infections may lower mortality rates. Further large-scaled epidemiological studies are needed.