Occult infection in the facial area presenting as fever of unknown origin

Dental infections, otitis media or sinusitis may present as fever of unknown origin (FUO), lacking local symptoms and signs. Physicians are often unaware of this possibility, since current textbooks and major articles do not mention occult facial infections among the causes of FUO. Patients with FUO typically undergo a laborious series of uncomfortable, time-consuming, expensive and often unnecessary investigations in the search for the cause of pyrexia. We report five such patients from a community hospital, representing 14% of cases in a series of patients with FUO. In most of these patients local signs were absent, laboratory investigations were noncontributory, and antibiotic treatment was ineffective. Surgical drainage of pus collections was followed a few days later by defervescence. We suggest that occult infections in the facial area should be considered among the common causes of FUO, and careful dental examination, otoscopy and X-rays of the teeth and sinuses should be included early in the investigation of these patients.