title: Aerobic and anaerobic microbiology of external otitis.
abstract: Microbiological and clinical data from 46 patients with external otitis were retrospectively evaluated. Specimens were processed for isolation of aerobic and anaerobic bacteria. A total of 42 aerobic bacteria, 22 anaerobic bacteria, and 3 Candida albicans organisms were recovered. Aerobic bacteria only were isolated from 31 patients (67%), anaerobic bacteria only were isolated from 8 (17%), and mixed aerobic and anaerobic bacteria were isolated from 4 (9%). C. albicans alone was recovered from two patients (4%), and the organism was mixed with aerobic bacteria in one case (2%). The most common isolates were Pseudomonas aeruginosa (19 instances), Peptostreptococcus species (11), Staphylococcus aureus (7), and Bacteroides species (5). One isolate was recovered from 30 patients (65%), 2 isolates were recovered from 11 (24%), and 3 isolates were recovered from 5 (11%). beta-Lactamase activity was detected in 32 isolates recovered from 27 specimens (59%). These data illustrate the polymicrobial nature of external otitis in one-third of the patients and the role of anaerobic bacteria in one-quarter of them. Further prospective studies are warranted for evaluating the role of anaerobic bacteria in this infection and the therapeutic implications of these findings.
authors.affiliation: Department of Pediatrics, Naval Medical Center, Bethesda, Maryland.
authors.forename: I
authors.initials: I
authors.lastname: Brook
authors.forename: E H
authors.initials: EH
authors.lastname: Frazier
authors.forename: D H
authors.initials: DH
authors.lastname: Thompson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001420:Bacteria, Aerobic / Q000302:isolation & purification*; D001421:Bacteria, Anaerobic / Q000302:isolation & purification*; D001424:Bacterial Infections / Q000453:epidemiology* / Q000382:microbiology; D002648:Child; D004424:Ear Canal / Q000382:microbiology*; D005260:Female; D006772:Hospitals, Military; D006801:Humans; D008297:Male; D008875:Middle Aged; D010032:Otitis Externa / Q000453:epidemiology / Q000382:microbiology*; D012189:Retrospective Studies