Fever of unknown origin in adults: evaluation of 144 cases in a non-university hospital.

The spectrum of diseases found in series of fever of unknown origin shows variation in relation to selection bias; particularly, selection of the most difficult cases in tertiary reference university centres. We present a series of 144 patients presenting to a non-university hospital between 1999 and 2005 (secondary level of the health care system) with a community-acquired fever of unknown origin. In 37 cases (25.7%), the reason for fever could not be explained. Among the 107 patients with a final diagnosis (74.3%), non-infectious inflammatory disorders represented the most prevalent category (35.5%), surpassing infections (30.8%), miscellaneous causes (20.6%) and malignancies (13.5%). 13 entities accounted for over 68% of diagnoses (sinusitis and occult dental infections, Q fever, Epstein-Barr virus and cytomegalovirus infections, lymphoma, colo-rectal adenocarcinoma, adult-onset Still disease, systemic lupus erythematosus, giant cell arteritis and/or polymyalgia rheumatica, rheumatoid arthritis, polyarteritis nodosa, factitious fever and habitual hyperthermia). As demonstrated in other studies, non-infectious inflammatory diseases emerge as the most prevalent diagnostic category. Giant cell arteritis and polymyalgia rheumatica were particularly frequent in the elderly. Epstein-Barr virus and cytomegalovirus infections and habitual hyperthermia were particularly frequent in the youngest patients. There were no major differences in repartition of diagnostic categories between this series and historical university series.