The increasing incidence of Ampicillin-resistant Haemophilus influenzae. A cause of otitis media

Abstract

Middle ear exudate was obtained by myringotomy or aspiration from 625 suburban children, aged 1 mo. to 12 yr, who had acute otitis media; bacterial pathogens were isolated from 71%. Haemophilus spp. were isolated from 212 (29%) and Streptococcus pneumoniae from 205 (28%). From 1975 to Aug. 1977, the number of Haemophilus isolates resistant to ampicillin appreciably increased. Currently, 8% of all cases of acute otitis media in the Washington, DC, area [USA] are due to H. influenzae resistant to ampicillin. Of 35 patients with resistant H. influenzae otitis, 31 were treated with an erythromycin/sulfisoxazole combination with an impressive clinical response. Of these 31 cases, 26 failed to have H. influenzae eradicated by an average of 10 days of oral ampicillin in recommended doses.