Treatment of otitis media caused by Hemophilus influenzae: evaluation of three antimicrobial regimens.

Ninety young children with otitis media, proven by tympanocentesis culture to be due to Hemophilus influenzae, were treated in a prospective double-blind study with one of three antimicrobial regimens: ampicillin, erythromycin ethylsuccinate, or erythromycin ethylsuccinate with concomitant trisulfapyrimidines. Results of efficacy evaluation indicated that the combination was as effective as ampicillin and statistically superior to erythromycine alone. Of the strains of H influenzae identified, 15/9 were typable with 12/9, type b. In vitro sensitivity tests indicated that the strains were sensitive to the amtimicrobials studied in clinically attainable levels; however, comparison of individual efficacy ratings with sensitivity results indicated that some children in each treatment group failed to respond as predicted.