SUSCEPTIBILITY OF BETA-HEMOLYTIC STREPTOCOCCI TO 9 ANTIMICROBIAL AGENTS AMONG 4 MEDICAL-CENTERS IN SALT-LAKE-CITY, UTAH, USA

A multicenter study was performed to evaluate the susceptibility of be ta-hemolytic streptococci to nine antimicrobial agents. MICs were perf ormed in cation-supplemented Mueller-Hinton broth with 3.5% lysed shee p red blood cells according to NCCLS guidelines. A total of 646 isolat es were tested: 300 (46%) group A; 170 (26%) group B; 38 (6%) group C, 35 (5%) group F; 83 (17%) group G; and 20 (3%) nongroupable. Six perc ent of the total isolates were resistant to one or more of the antibio tics rested. Approximately 7% of 387 strains from the University of Ut ah Hospital and Clinics were resistant to erythromycin. Four isolates were resistant to clindamycin. Six strains (3%) from Primary Children' s Medical Center (207 tested) were resistant to one or more of the mac rolides. Resistance was rare at the LDS Hospital and the Salt Lake Vet eran's Affairs Hospital. Overall, resistance among beta-hemolytic stre ptococci in this geographic location does not seem to be a significant problem, except at the tertiary care University hospital. (C) 1997 El sevier Science Inc.