Retrospective analysis of 1,641 cases of classic fever of unknown origin

Abstract

Background: Fever of unknown origin (FUO) is commonly defined as fever higher than 38.3 ℃ on several occasions during at least 3 weeks with uncertain diagnosis after a number of obligatory investigations. It is a special type of fever and a common disease in internal medicine. However, due to its complex etiology, lack of characteristic clinical manifestations, and insufficient laboratory examination indicators, it often baffles clinicians in diagnosis. We herein present a study of the etiological factors and clinical features of classic fever of unknown origin (FUO) to provide help for related clinical diagnosis and treatment.Methods: A total of 1,641 cases of patients with classic FUO hospitalized in West China Hospital of Sichuan University between January 1, 2011 and December 31, 2017, were collected, and the etiological factors of classic FUO were analyzed. A special effort was made to explore and screen the laboratory indicators related to infectious diseases, and the above data were compared with the clinical features of tuberculosis and lymphoma, which are difficult to diagnose.Results: Among the 1,641 patients, 1,504 were finally diagnosed through various types of examination or diagnostic methods, and the diagnosis rate was 91.65%. Among all the causes of the 1,641 cases of FUO, 48.69% [799] were infectious diseases, of which tuberculosis was the most common, accounting for 19.50%[320]. Connective tissue diseases were responsible for 19.26% [316] of cases, of which adult-onset Still's disease (AOSD) was the most common, comprising 89 (5.42%) of the cases; 16.94% [278] were neoplastic diseases, and lymphoma (143, 8.71%) cases, was the most common malignant tumor; 6.76% [111] were other diseases; and in 8.35% [137] of cases, the cause was unclear. Through comparative analysis of tuberculosis and lymphoma, no significant differences were found between the symptoms, signs, and non-specific routine examination results of the two diseases. The diagnosis of these diseases was more dependent on tuberculosisrelated examinations and pathological examinations.Conclusions: Infectious diseases are the principal cause of classic FUO, in which tuberculosis accounts for a large proportion. Non-infectious diseases that cause FUO are mainly connective tissue diseases and malignant tumors. Of the various causes of classic FUO, tuberculosis and lymphoma are relatively difficult to diagnose. In most cases, the causes of classic FUO can be ascertained.

Adult-Onset Still’s Disease: Clinical Aspects and Therapeutic Approach

“…In a large retrospective study, which set out to analyse 1641 patients with fever of unknown origin (FUO), AoSD was responsible for 5.4% of cases [ 36 ]. Overall, rheumatic diseases comprise approximately 30% of cases with FUO, with AoSD being the most frequent group [ 37 ].…”

Clinical Features and Long-term Outcomes of Lymphoma Patients Initially Presenting as Fever With Unknown Origin

“…Previous studies merely focused on the total population of lymphoma patients with FUO. 3,15,16 In Zhou et al's study, 15 the median age of lymphoma patients with FUO was 42 years old and the prevalence of male was 48.3%. In our study, the median age of the FUO group in NK/T-CL was 42.0 years old, which was consistent with Zhou's study.…”

“…The laboratory examinations of lymphoma patients with FUO were usually abnormal according to previous studies. 15,16 In our study, further subgroup analyses were performed to compare the differences in laboratory index between the FUO and non-FUO groups strati ed with four pathological subtypes. Our study found that, for patients with B-NHL or T-NHL, there was a higher incidence of EBV positive in the FUO group.…”

Diffuse Large B-Cell Lymphoma of the Mandible Diagnosed by Metagenomic Sequencing: A Case Report

“…Fever of unknown origin can be attributed to many factors, including infection (40%), neoplastic disease (20%), collagen-vascular disease (15%) and so on ( 16 ). A retrospective study found that tuberculosis was the most common cause of infectious fever and lymphoma was the most common cause of neoplastic fever ( 17 ). In this case, the hemogram and blood biochemistry of the patient were basically normal, CRP and ESR were slightly elevated, indicating inflammatory reaction.…”