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Simple inoculum standardizing system for antimicrobial disk susceptibility tests.

A L Barry·D Amsterdam·M B Coyle·E H Gerlach·C Thornsberry·R W Hawkinson
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Abstract

A collaborative study was undertaken to evaluate a simple, convenient device which expedites inoculum standardization for antimicrobial disk susceptibility tests. The Inocupac system (Minnesota Mining & Manufacturing [3M] Co., St. Paul, Minn.) was used to perform disk tests in parallel with the standard Bauer-Kirby method. Five investigators tested 100 selected isolates, each in triplicate. Inter- and intralaboratory precision of both disk procedures was essentially comparable. The Inocupac system failed to consistently provide satisfactory growth with some streptococci, but when testing common gram-negative bacilli, staphylococci, and most enterococci, the Inocupac system gave zones about the same size (+/-2 mm) as the Bauer-Kirby procedure. Interpretive agreement between the two test systems varied from 90 to 99% with different antimicrobial agents, and repeated tests with the Bauer-Kirby method demonstrated the same degree of interpretive agreement. The Inocupac system is a valid alternative method for inoculating disk susceptibility tests.

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Anti-Bacterial AgentsEnterobacteriaceaeEvaluation Studies as TopicMicrobial Sensitivity TestsPseudomonas aeruginosaStaphylococcusStreptococcusComparative StudyJournal Article

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A L Barry, D Amsterdam, M B Coyle, E H Gerlach, C Thornsberry, R W Hawkinson. 1979. Simple inoculum standardizing system for antimicrobial disk susceptibility tests.. https://doi.org/10.1128/jcm.10.6.910-918.1979

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