Current Status of Ampicillin-Resistant Hemophilus influenzae Type b

Abstract

At its meeting on April 16, 1975, the Committee on Infectious Diseases reconsidered the problem of ampicillin-resistant strains of Hemophilus influenzae type b. The following facts were noted: (1) Strains of H. influenzae type b highly resistant in vitro to ampicillin have been reported from 20 states and the District of Columbia.1 (2) These strains were isolated from children with sepsis, meningitis, cellulitis, epiglottitis, suppurative arthritis, and pneumonia. Some of the children died when the resistance of the etiologic strain was not appreciated. (3) The prevalence of these strains is still uncertain but appears to be at a low level in most communities. Epidemiologic studies, however, indicate these strains may infect many children in closed communities, such as day-care centers.2 The Committee believes a modification of its prior statement3 is warranted based on the wide-spread occurrence of these strains: (1) Initial management of children with documented or suspected severe infection due to H. influenzae type b (including meningitis, epiglotitis and sepsis) should include a parenteral penicillin (penicillin G or ampicillin) and intravenous chioramphenicol. (2) All strains of H. influenzae type b should be tested for susceptibility to ampicillin as early as possible. (3) Ampicillin alone as initial therapy for children with severe infections that may be due to H. influenzae should be considered only in areas of the country where ampicillin-resistant strains of H. influenzae type b have not appeared and where active programs of bacterial surveillance and rapid laboratory diagnosis of susceptibility to antimicrobial agents are available. The dosage schedules, rationale for combined therapy as initial management, and description of susceptibility tests for H. influenzae are given in the initial Committee Report.3