Susceptibilities of genital mycoplasmas to the newer quinolones as determined by the agar dilution method.

Abstract

The increasing resistance of genital mycoplasmas to tetracycline poses a problem because tetracycline is one of the few antimicrobial agents active against Mycoplasma hominis, Ureaplasma urealyticum, chlamydiae, gonococci, and other agents of genitourinary-tract disease. Since the quinolones are a promising group of antimicrobial agents, the susceptibilities of M. hominis and U. urealyticum to the newer 6-fluoroquinolones were determined by the agar dilution method. Ciprofloxacin, difloxacin, and ofloxacin had good activity against M. hominis, with the MIC for 50% of isolates tested (MIC50) being 1 microgram/ml. Fleroxacin, lomefloxacin, pefloxacin, and rosoxacin had MIC50s of 2 micrograms/ml. Enoxacin, norfloxacin, and amifloxacin had MIC50s of 8 to 16 micrograms/ml, and cinoxacin and nalidixic acid were inactive (MIC50, greater than or equal to 256 micrograms/ml). Overall, the activities of 6-fluoroquinolones for ureaplasmas were similar to those for M. hominis, with MICs being the same or twofold greater. The most active 6-fluoroquinolones against ureaplasmas were difloxacin, ofloxacin, and pefloxacin, with MIC50s of 1 to 2 micrograms/ml. Ciprofloxacin was unusual in that the MIC50 for M. hominis was 1 microgram/ml, whereas the MIC50 for ureaplasmas was 8 micrograms/ml. Since the MIC50s for the most active quinolones approximate achievable concentrations in blood and urine, quinolones have promise in treating mycoplasmal infections.

• Authors: G E Kenny, T M Hooton, M C Roberts, F D Cartwright, J Hoyt
• Journal: Antimicrobial agents and chemotherapy (Antimicrob Agents Chemother) Vol. 33 Issue 1 Pg. 103-7 (Jan 1989) ISSN: 0066-4804 [Print] United States
• PMID: 2712541 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• 4-Quinolones
• Anti-Infective Agents

Topics

• 4-Quinolones
• Anti-Infective Agents (pharmacology)
• Colony Count, Microbial
• Microbial Sensitivity Tests
• Mycoplasma (drug effects)
• Ureaplasma (drug effects)
• Urogenital System (microbiology)