Detection of beta-lactamase produced by Staphylococcus intermedius
Hoskins, J.D.; Newman, S.S.; Roy, A.F.; Foil, C.S.; Cox, H.U.
American Journal of Veterinary Research 46(7): 1526-1528
1985
ISSN/ISBN: 0002-9645 PMID: 3875302 Document Number: 256356
One iodometric, 2 chromogenic, and 3 acidometric methods were compared for the detection of beta-lactamase produced by Staphylococcus intermedius (n = 105) isolated from dogs. Of 575 tests performed, using the 6 methods evaluated, 316 (55.0%) were positive for beta-lactamase production. The iodometric method was the reference method. With the exception of a high correlation (r = 0.962) between 1 acidometric method and 1 chromogenic method, the 5 commercial methods had correlation coefficients less than 0.900 when comparisons were made among them. The 6 methods were in agreement for 69 (65.7%) of the isolates. Based on the findings of this study, an inexpensive, laboratory-prepared, paper strip iodometric method was as reliable as 5 commercial methods for beta-lactamase detection and is recommended for routine use in clinical laboratories.