Differential expression of lactic acid isomers, extracellular matrix metalloproteinase inducer, and matrix metalloproteinase-8 in vaginal fluid from women with vaginal disorders

ObjectiveDo metabolites in vaginal samples vary between women with different vaginal disorders. DesignCross-sectional study. SettingCampinas, Brazil. SampleSeventy-seven women (39.9%) with no vaginal disorder, 52 women (26.9%) with vulvovaginal candidiasis (VVC), 43 women (22.3%) with bacterial vaginosis (BV), and 21 women (10.9%) with cytolytic vaginosis (CTV). MethodConcentrations of d- and l-lactic acid, extracellular matrix metalloproteinase inducer (EMMPRIN), and matrix metalloproteinase-8 (MMP-8), and the influence of Candida albicans on EMMPRIN production by cultured vaginal epithelial cells, were determined by enzyme-linked immunosorbent assay (ELISA). Associations were determined by the Mann-Whitney U-test and by Spearman's rank correlation test. Main outcome measuresMetabolite levels and their correlation with diagnoses. ResultsVaginal concentrations of d- and l-lactic acid were reduced from control levels in BV (P<0.0001); l-lactic acid levels were elevated in CTV (P=0.0116). EMMPRIN and MMP-8 concentrations were elevated in VVC (P<0.0001). EMMPRIN and l-lactic acid concentrations (P0.008), but not EMMPRIN and d-lactic acid, were correlated in all groups. EMMPRIN also increased in proportion with the ratio of l- to d-lactic acid in controls and in women with BV (P0.009). Concentrations of EMMPRIN and MMP-8 were correlated in controls and women with VVC (P0.0002). Candida albicans induced EMMPRIN release from vaginal epithelial cells. ConclusionsVaginal secretions from women with BV are deficient in d- and l-lactic acid, women with VVC have elevated EMMPRIN and MMP-8 levels, and women with CTV have elevated l-lactic acid levels. These deviations may contribute to the clinical signs, symptoms, and sequelae that are characteristic of these disorders.