Spurious ampicillin resistance by testing Haemophilus influenzae with agar containing supplement C.

نویسندگان

  • J A Washington
  • R J Snyder
  • P C Kohner
چکیده

Ampicillin resistance (minimal inhibitory concentration >/=10 mug/ml) in the absence of beta-lactamase activity by Haemophilus influenzae was noted in tests performed with Mueller-Hinton agar containing one lot of supplement C. All strains, except five with known resistance due to beta-lactamase activity, were inhibited by 0.6 mug or less of ampicillin per ml of chocolatized blood agar.

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عنوان ژورنال:
  • Antimicrobial agents and chemotherapy

دوره 9 1  شماره 

صفحات  -

تاریخ انتشار 1976