Unexplained fever in the ED: analysis of 139 patients.

This study examined consecutive patients with unexplained fever (UF) presenting to the ED to define their characteristics and to compare distinctive parameters between admitted and discharged patients. During a 3-month period, all adult patients presenting to the ED with UF were prospectively followed for 1 month. Of 139 patients with UF, 58 patients (42%) were admitted to the hospital, whereas 81 patients (58%) were discharged. Whereas most of the discharged patients had self-limited febrile disease and eventually recovered, the admitted patients had more unresolved fever, serious infections, or systemic diseases and a 5% mortality rate. The admitted patients were older, had more comorbidity, higher leukocyte count, and anemia, but not a higher degree of fever. Older age, comorbidity, leukocytosis, and anemia, but not higher degree of fever, should direct the decision toward admission of a patient with UF.