Fever of unknown origin in elderly patients

Abstract

Introduction. Causes of fever of unknown origin are different. It is considered that it can be caused with over 200 different clinical entities. Aetiological causes differ according to different categories of age. Febricity in the elderly is at most the result of autoimmune processes, malignancies, bacterial infections and vasculitis. Objective. The aim of this study was to determine the most common characteristics of fever, the most common laboratory, bacterial and viral tests and to analyze applied therapy in patients with unknown febrile state, and to affirm final diagnosis in elderly patients, as well as younger than 65 years old, and to define outcome of disease in both groups of patients. Methods. Research comprised 100 patients who had been treated at the Infectious Disease Clinic of the Clinical Centre of Vojvodina in Novi Sad, during a three-year period, and in whom fever of unknown origin had been diagnosed. Patients were divided into two homogenous groups of 50 people. The first one (S) consisted of patients older than 65 years, and the second, control group (K) was constituted of patients younger than the age of 65. All of them were chosen by random sample method. Results. Average results of standard laboratory parameters of infection were obtained, such as erythrocyte sedimentation rate (ESR), fibrinogen, CRP, and especially leukocyte, and those were significantly higher in the group of elderly patients. The cause had not been found in 10% of elderly patient group, and in the younger group, not even in the third of patients. Among known causative agents dominant were infections, usually of respiratory and urinary tract, in both tested groups. Even 28% of the elderly had sepsis, and 10% endocarditis. Malignant diseases were more frequent in group of the elderly patients, and immune i.e. systematic disorders were evenly noticed in both groups of patients. Conclusion. Despite advanced studies in medicine, and existence of modern diagnostic procedures, fever of unknown origin is still today differential diagnostic problem.