title: Methicillin-resistant Staphylococcus aureus susceptibility testing by an automated system, Autobac I.
abstract: The Autobac I system was used to evaluate the antibiotic susceptibility pattern of methicillin-resistant Staphylococcus aureus isolates. The results of the Autobac I were compared with the results of the disk diffusion method. The disk diffusion susceptibility pattern showed resistance to methicillin/oxacillin, penicillin, erythromycin, clindamycin, and kanamycin. All isolates were susceptible to cephalothin, chloramphenicol, tetracycline, and gentamicin. There was at least 96% agreement using the Autobac I system with all antibiotics except methicillin and clindamycin. Seventy percent of 57 isolates were recorded as susceptible to methicillin, whereas 9% had an intermediate susceptibility. With clindamycin, 14% were recorded as susceptible and 7% were recorded as intermediate. Upon prolonged incubation of the Autobac I cuvette, the agreement between the two methods was 44% for methicillin and 93% for clindamycin. Changes in the environmental conditions, such as use of 5% sodium chloride broth and a 32 degrees C incubation temperature, did not increase the detection of methicillin-resistant isolates by the Autobac I system.
mesh_terms: D001434:Bacteriophage Typing; D005069:Evaluation Studies as Topic; D008712:Methicillin / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests / Q000295:instrumentation* / Q000379:methods; D010403:Penicillin Resistance; D013211:Staphylococcus aureus / Q000187:drug effects*
chemical_list: D008712:Methicillin
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