Haemophilus influenzae Type B Resistant to Ampicillin

Abstract

Recently, two infants with severe infections due to ampicillin-resistant strains ofHaemophilus influenzaetype B were treated at Children's Hospital National Medical Center. In both cases, it was necessary to change therapy to chloramphenicol. One patient with meningitis died while the second with bacteremia and pneumonia recovered. A survey of 60 recent isolates ofH influenzaetype B in the Washington community showed that 10% were ampicillin-resistant. The enzyme produced by these resistant strains was found to be a β-Iactamase. Careful appraisal is now necessary to decide whether ampicillin is the drug of choice as initial therapy inH influenzaemeningitis in pediatric patients. (JAMA229:298-301, 1974)