Fever of Unknown Origin. A Study of 52 Cases

Background: fever of unknown origin is a clinical syndrome of great diagnostic complexity. Only two clinical studies related to this subject have been published in Cuba, hence it is important the compilation of a series of cases where an accurate diagnostic method was applied to determine its most common causes. Objective: to describe the most frequent causes of fever of unknown origin. Methods: a case-series study of 52 patients admitted to the Freyre de Andrade Clinical-Surgical Hospital with a diagnosis of fever of unknown origin was conducted from 2000 to 2010. The study variables included: age, sex, complementary studies (variables from humoral, microbiological and imaging investigations and biopsies), results obtained and medical management established according to them, diagnosis of each patient, treatment and clinical course. Results: of all patients, 37(71 %) had infections, nine suffered from infectious endocarditis. Nine (16 %) had neoplasms; seven of them were hematopoietic. Three patients (6 %) were diagnosed with non-infectious inflammatory disease. Conclusions: the first cause of fever of unknown origin is bacterial infection, primarily infectious endocarditis and tuberculosis. The second cause is hematopoietic neoplasm and particularly the non-Hodgkin's lymphoma.