National Institute of Child Health and Human Development.

Objective To examine associations between the composition of the vaginal microbiota and genitourinary menopausal symptoms, serum estrogen, and vaginal glycogen. Methods For this cross-sectional study, 88 women ages 40–62 enrolled in a hot flash treatment trial provided vaginal swabs and a blood sample at enrollment. Bacterial communities were characterized using 16S rRNA PCR and deep sequencing targeting the V3-V4 region. Quantities of Lactobacillus crispatus and L. iners were measured using qPCR. Self-reported genitourinary symptoms included: 1) presence and severity of individual symptoms and 2) identification of most bothersome symptom. Glycogen was measured fluorometrically in swab eluate. Serum estradiol (E2) and estrone (E1) were measured by liquid chromatography/mass spectrometry. Associations between bacteria, symptoms, glycogen, and serum estrogens were tested by linear regression or Wilcoxon signed-rank test, adjusted for multiple comparisons. Comparisons between groups used Kruskall-Wallis or Fisher’s exact test. Results Of the 88 women, 33 (38%) had a majority of Lactobacillus species, while 58 (66%) had any Lactobacillus detected. Over half (53%) reported ≥ 1 vulvovaginal symptom (most commonly dryness), but symptoms were not associated with the presence of Lactobacillus species. Women with Lactobacillus dominant communities had higher unconjugated serum estrone, but no difference in vaginal glycogen levels, compared to those with non-Lactobacillus dominant communities. Higher serum E2 and E1 were not associated with higher vaginal glycogen, nor detection of individual genera. Conclusions Presence of Lactobacillus-dominant vaginal microbiota was not associated with fewer vulvovaginal symptoms. Serum estrone was higher in women with Lactobacillus-dominance, but vaginal free glycogen was not associated with composition of the vaginal microbiota.

Background Nongonococcal urethritis (NGU) is a common syndrome with no known etiology in up to 50% of cases. We estimated associations between urethral bacteria and NGU in men who have sex with men (MSM) and men who have sex with women (MSW). Methods Urine was collected from NGU cases (129 MSM; 121 MSW) and controls (70 MSM; 114 MSW) attending a Seattle STD clinic. Cases had ≥5 polymorphonuclear leukocytes on Gram stain plus symptoms or discharge; controls had <5 PMNs, no symptoms, no discharge. NGU was considered idiopathic when Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, Trichomonas vaginalis, adenovirus, and herpes simplex virus were absent. The urethral microbiota was characterized using 16S rRNA gene sequencing. Compositional lasso analysis was conducted to identify associations between bacterial taxa and NGU, and to select bacteria for targeted quantitative PCR (qPCR). Results Among NGU cases, 45.2% were idiopathic. Based on compositional lasso analysis, we selected Haemophilus influenzae (HI) and Mycoplasma penetrans (MP) for targeted qPCR. Compared to 182 men without NGU, the 249 men with NGU were more likely to have HI (14% vs. 2%) and MP (21% vs. 1%) (both p≤0.001). In stratified analyses, detection of HI was associated with NGU among MSM (12% vs. 3%, p=0.036) and MSW (17% vs. 1%, p<0.001), but MP was associated with NGU only among MSM (13% vs. 1%, p=0.004). Associations were stronger in men with idiopathic NGU. Conclusions HI and MP are potential causes of male urethritis. MP was more often detected among MSM than MSW with urethritis.