Antimicrobial drug susceptibility of respiratory isolates of Hemophilus influenzae from adults.

Hemophilus influenzae isolates from sputum of 111 patients with chronic bronchitis were tested for susceptibility to 8 antimicrobial drugs. A new beta-lactam, LY-127935, was the most active agent tested. Ampicillin, cefamandole, tetracycline, and cefuroxime showed good activity against most isolates. Two strains, both nontypable, were resistant to ampicillin and produced beta-lactamase. Cefaclor was somewhat less effective, although most strains were susceptible. Erythromycin and cephalexin were of limited utility.