Assessment of Vaginal Lactobacillary Flora in Wet Mount and Fresh or Delayed Gram's Stain

[摘要] Objective:The assessment of the vaginal lactobacillary flora helps to direct further diagnostic microbiologicinvestigations in genital infectious disease and seems to represent a powerful tool in predictinginfectious morbidity and preterm labor during pregnancy. In the absence of a “gold standard,” westudied the variations in assessing lactobacillary morphotypes according to the method used.Methods:The lactobacillary flora from 183 pregnant women was classified according to 3 groups:normal, intermediate, and abnormal. This grading of lactobacilli was appled to vaginal and cervicalspecimens by means of 1) immediate wet-smear microscopy, 2) Gram's stain on a fresh, air-dried specimen,and 3)delayed Gram's stain after specimen transportation in Stuart's growth medium for 3–6 h.Results:The assignment of intermediate or abnormal flora (grade II or grade III) showed highconcordance rates among the different preparatory techniques, but the assignment of grade I (normalflora) did not. Fewer lactobacilli were found 2.6 times more often after Gram's stains of freshspecimens [Relative Risk (RR) 2.6, 95% confidence interval (CI) 1.7–4.1] and 6 times more oftenwhen the Gram%s stain was performed in a delayed examination after transport than in a freshwet-mount specimen (RR 6.2, 95% CI 2.5–15.6). Disturbed lactobacillary grades were also foundmore frequently in specimens from the cervix than those from the vagina (RR 4.0, 95% CI, 1.5–10.4).Conclusions:There are discrepancies in the diagnosis of lactobacillary grades between gram-stainedand fresh vaginal specimens. The evidence is ambiguous as to which of the 2 methods isresponsible. If an evaluation is to be done on a gram-stained specimen, then the storage of thesample in Stuart transport medium before staining should be avoided.

[学科分类] 妇产科学