INFECTIOUS DISEASE Systemic Hemophilus influenzae Infection A Study of Risk Factors

and accepted January 1982. In Omaha, from 1974 to 79, 30 (12.5%) of 240 patients with Haemophilus influenzae bacteremia or meningitis had a wide variety of conditions known to be associated with increased susceptibility to bacterial infection. Neonates and adults accounted for 47 per cent of the infections. Non-type b and non-typable strains caused 41 per cent of the episodes. Forty-one per cent of patients had bacteremia with no detectable focus of infection. The incidence of meningitis was low. Mortality was 28 per cent, considerably higher than in patients who were previously healthy. A review of the medical literature indicated that low-birth weight infants and patients with leukemia and other malignancies undergoing chemotherapy, splenectomy, congenital asplenia, sickle cell anemia, immunoglobulin deficiency diseases, cerebrospinal fluid shunts, and skull de-fects are at greater risk for systemic H. influenzae disease than the general population. THE USUAL DESCRIPTION of the patient with systemic Haemophilus influenzae disease is that of a previously healthy infant or young child who is infected with type b organisms and has an identifiable focus of infection, such as epiglottitis or meningitis. However, analysis of cases of H. influenzae bacter-emia or meningitis from a city-wide surveillance sys-tem indicated that this characterization is incomplete. A substantial proportion of patients had a predispos-ing condition, were newborns or adults, had infecting strains that were non-type b or non-typable, and had no focus of infection. ~~~r~~~ ~ and, ~~h~~~ This survey, early results of which have been pub-1,.,sh,--d,l included all with ~~. ~~~~~~~~~ ~ bac-teremia and meningitis at the University of Nebrask