A great deal of youngsters suffer from otitis media, for which antimicrobials are frequently prescribed. Increased antimicrobial resistance forces physicians to judiciously use antimicrobial agents in treating patients with acute otitis media. There have however been few references with regard to otitis media in Korean children, and authors proceeded investigation to look for the causative agents of otitis media in Korean children and their antimicrobial susceptibility.

The study included 65 patients younger than 15 years old who had been cared at the department of pediatrics and otolaryngology in Hanyang University Hospital from July 1994 to June 1999, and diagnosed of otitis media with otorrhea which contained microorganisms isolated in otorrhea culture. The medical records were reviewed for demographic data, isolated organisms and their antimicrobial susceptibility.

Among 65 patients, 37(57%) were boys and 28(43%) girls. Distribution of the patients was reciprocal to the age of the patients; 27 patients(41.5%) were younger than 1 year old, 24(36.9%) were 1 to 3 years old with the average of 2.9 years of age. Staphylococus aureus was isolated in 32 patients(49.2%), Streptococcus pneumoniae in 19 patients(29.2 %) Haemophilus inf luenzae in 9 patients(13.8%), Streptococcus oralis in 3 patients(4.6%), Moraxella catarrhalis in 1 patient(1.5%). The isolated microorganisms were not different whether patients had cleft lip/palate or not. The antibiotic resistance rates of S. aureus were ≥90 % to erythromycin, imipenem, cephalothin, and clindamycin, 86.2% to oxacillin, 25% to chloramphenicol, 12.5% to trimethoprim/sulfamethoxazole(TMP/SMX), and 0% to vancomycin and teicoplanin. The antibiotic resistance rates of S. pneumoniae were 71.4% to penicillin and greater than 60% to erythromycin, tetracycline, TMP/SMX, 7.1% to chloramphenicol, and 0% to vancomycin and teicoplanin. The antibiotic resistance rates of H. influenzae were 55% to ampicillin and TMP/SMX, and 0% to chloramphenicol, ceftriaxone, aztreonam, imipenem and ciprofloxacin.

With otorrhea culture, the causative organisms of otitis media appear to be S. aureus, S. pneumoniae and H. influenzae. The high antibiotic resistance rates of the isolated organisms should affect the choice of antibiotics in treating patients with otitis media. Prospective investigations utilizing tympanocentesis in microbiologic studies are needed.