Previous studies of BC have reported conflicting data on the incidence of co-existent bacteremia and meningitis. Otitis media (OM) is reportedly found in 75% of patients and, when unilateral, is said to always occur on the ipsilateral side (suggesting lymphangitic spread to the cheek). To more accurately define the clinical picture of BC, we reviewed the records of 55 children with a clinical diagnosis of primary (no overlying skin trauma) BC. There were 32 males and 23 females with a median age of 11 (range 1.5-64) months. OM was present in 22 (40%) patients. The contralateral ear was involved in 5 of 13 patients with unilateral OM. Blood cultures were positive in 27 (53%) of 51 patients and grew H. influenzae b (HIB) in 25 (92.5%). Two infants with S. pneumoniae and S. agalactiae infections were clinically indistinguishable from the remaining patients. Cellulitis cultures were positive in 6 (17%) of 35 attempts. Cerebrospinal fluid (CSF) cultures were positive in 3 (9.4%) of 32 patients; one additional child whose CSF was not initially examined later developed meningitis. These data suggest that: (a) bacteremia is commonly present in BC, (b) the pathogenesis of BC does not usually involve lymphangitic extension from the middle ear, (c) lumbar punctures should always be performed because of the associated risk of meningitis and (d) BC is predominately but not exclusively due to HIB. Initial therapy should include parenteral antimicrobial coverage for HIB and Gram positive organisms.