[A retrospective study of hospitalized patients with fever of unknown origin (FUO) past six years].

We analysed retrospectively 48 hospitalized patients with fever of unknown origin (FUO) from 1982 through 1988. The criteria of FUO were (1) temperature of more than 38.3 degrees C documented on several occasions (2) overall duration of illness more than three weeks, (3) uncertain diagnosis till one week after hospitalization. Of this group of FUO, 25 patients (52.1%) were found to have infections, 8 patients (16.7%) had collagen disorders, 7 patients (14.6%) had neoplastic disorders, 3 patients (6.3%) were crohn disease and 5 patients (10.4%) were undiagnosed. Among infectious diseases, chronic tonsillitis was the most frequent (5 patients: 20%) and they were diagnosed by the provocative examination. Non bacterial meningitis and cervical lymphadenitis were diagnosed in all 3 patients (12% in all), Adult Still's disease was found in 3 patients (37.5%) and systemic lupus erythematosus (SLE) in 2 patients (25%) in collagen disease. Immunoblastic lymphadenopathy was diagnosed in 3 patients (42.9%) of malignant diseases. Three cases of Crohn disease were revealed in all the patients of the miscellaneous group. Duration of fever was relatively short in infection diseases compared to malignant and Crohn diseases. The most common laboratory abnormality is an elevated erythrocyte sedimentation rate (89.6%). As the final diagnosis of FUO are changing with the development of diagnostic techniques, a new criteria of FUO is necessary.