Antimicrobial Susceptibilities of Ureaplasma urealyticum and Mycoplasma hominis in Pregnant Women

Abstract

Background: Ureaplasma urealyticum and Mycoplasmahominis are associated with an increased risk ofpregnancy complications, such as preterm birth andpremature membrane rupture. The purpose of thisstudy was to determine the isolation rates and antimicrobialsusceptibilities of genital mycoplasma in asample of pregnant women from Jinju, Korea.Methods: Vaginal swabs were obtained from 258 pregnantwomen between 2004 and 2008 and tested forthe presence of U. urealyticum and M. hominis atGyeongsang National University Hospital. The identificationand antimicrobial susceptibilities of U. urealyticumand M. hominis were determined with a commerciallyavailable kit, the Mycoplasma IST2 Kit (bioMe-rieux, Marcy-l’Etoile, France), and evaluated accordingto standards set by the Clinical and LaboratoryStandards Institute (CLSI).Results: U. urealyticum only was detected in 105specimens (38.6%), while M. hominis only was detectedonly in 2 specimens (1.8%). Seven specimens(6.7%) were positive both for U. urealyticum and M.hominis. Susceptibilities of U. urealyticum to azithromycin,erythromycin, clarithromycin, and doxycyclinewere 75.2%, 82.9%, 88.6%, and 88.6%, respectively,while almost all of the isolates were susceptible to josamycin(99.0%) and pristinamycin (100%). The susceptibilityof U. urealyticum to ofloxacin and ciprofloxacinwas 56.2% and 15.2%, respectively.Conclusion: The rate of isolation of genital mycoplasmain pregnant women was 44.2% in Jinju; mostof the mycoplasma were U. urealyticum. U. urealyticumand M. hominis were highly resistant to quinolones,but susceptible to josamycin. Therefore, empiricaltreatment without prior identification and determinationof the antimicrobial susceptibility of genitalmycoplasma will fail in many cases.