The in vitro activity of beta-lactamase inhibitors in combination with cephalosporins against M. tuberculosis.

Abstract

Although there are reports that the addition of a beta-lactamase inhibitor to ampicillin or amoxicillin greatly improves their in vitro activity against M. tuberculosis, there are no written reports about the antituberculosis effects of beta-lactamase inhibitors in combination with cephalosporins against M. tuberculosis. In this report, we have determined the minimal inhibitory concentrations (MIC) of 5 cephalosporins with or without combination with beta-lactamase inhibitor against M. tuberculosis strains isolated from patients before antituberculosis treatment and checked the production of beta-lactamase by bacteria before this procedure. Four strains of M. tuberculosis were contaminated during the experiment, and all the other 16 strains hydrolyzed the nitrocefin disc, thus indicating a beta-lactamase producer. The MICs of cephalosporins alone against M. tuberculosis were 200-400 micrograms/ml for ceforanide, 100-400 micrograms/ml for cephapirin, 400-1600 micrograms/ml for cefamandole, 200-1600 micrograms/ml for cefotaxime, and 800-1600 micrograms/ml for ceftriaxone. After adding the equimolar concentrations of sulbactam, the MICs were reduced to 100-200 micrograms/ml for ceforanide, 12.5-100 micrograms/ml for cephapirin, 100-400 micrograms/ml for cefamandole, 25-200 micrograms/ml for cefotaxime, and 100-800 micrograms/ml for ceftriaxone. We concluded that sulbactam enhanced the antituberculosis effect of cephalosporins.

• Authors: C H Chen, M H Yang, J S Lin, Y C Lee, R P Perng
• Journal: Proceedings of the National Science Council, Republic of China. Part B, Life sciences (Proc Natl Sci Counc Repub China B) Vol. 19 Issue 2 Pg. 80-4 (Apr 1995) ISSN: 0255-6596 [Print] China (Republic : 1949- )
• PMID: 7624446 (Publication Type: Journal Article)

Chemical References

• Cephalosporins
• beta-Lactamase Inhibitors
• Cefamandole
• Ceftriaxone
• Cephapirin
• ceforanide
• Cefotaxime
• Sulbactam

Topics

• Cefamandole (analogs & derivatives, pharmacology)
• Cefotaxime (pharmacology)
• Ceftriaxone (pharmacology)
• Cephalosporins (pharmacology)
• Cephapirin (pharmacology)
• Drug Synergism
• Microbial Sensitivity Tests
• Mycobacterium tuberculosis (drug effects)
• Sulbactam (pharmacology)
• beta-Lactamase Inhibitors