Disk diffusion susceptibility of Branhamella catarrhalis and relationship of beta-lactam zone size to beta-lactamase production

Antimicrob Agents Chemother. 1986 Nov;30(5):774-6. doi: 10.1128/AAC.30.5.774.

Abstract

We tested 231 isolates of Branhamella catarrhalis for beta-lactamase production and drug susceptibility by the National Committee for Clinical Laboratory Standards disk diffusion method. The nitrocephin disk (Cefinase) identified beta-lactamase in 98% of the enzyme-producing strains, and a zone diameter of inhibition of less than or equal to 29 mm for penicillin correctly predicted the presence of beta-lactamase in 99% of the isolates. No resistance to erythromycin, tetracycline, trimethoprim-sulfamethoxazole, or amoxicillin-clavulanic acid was observed.

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Methicillin / pharmacology
  • Microbial Sensitivity Tests
  • Moraxella / drug effects*
  • Moraxella / enzymology
  • Penicillin G / pharmacology
  • beta-Lactamases / biosynthesis*

Substances

  • Anti-Bacterial Agents
  • beta-Lactamases
  • Penicillin G
  • Methicillin