Accuracy of urethral swab and urine analysis for the detection of Mycoplasma hominis and Ureaplasma urealyticum in women with lower urinary tract symptoms

Our objective was to evaluate and compare the accuracy of urethral swabs and urine specimens in the detection of Mycoplasmas in women with lower urinary tract symptoms (LUTS). During a urogynecological work-up, including cystometry, we obtained first-void urine, urethral and vaginal swabs in 207 consecutive women at our urogynecological division. Mycoplasma hominis and Ureaplasma urealyticum as well as other microorganisms were detected by standard culture methods. 131 of 207 women reported LUTS. The other 76 formed the controls. Of 207 women 50 (24.2%) had positive cultures for Mycoplasmas. The prevalence of Mycoplasmas in women with LUTS (30.3%) was statistically significant and higher in the group without LUTS (14.5%) (p = 0.011). The detection of M. hominis was most accurate using urethral swab (Specificity 99.9%, PPV 99.6%) compared to the urine specimen (96%, 75%) and vaginal swab (95.1%, 67%). Similar results could be achieved for U. urealyticum (urethral swab: specificity 98.7%, PPV 96.3%; urine specimen: 86.8%, 72%; vaginal swab: 80.5%, 65.2%). In the subgroup of women less than 50 years an (detectable) infection due to Mycoplasma or Ureaplasma leads typically to LUTS with normal filling cystometry, whereas no such findings were relevant for the elderly women.