Cervical intraepithelial neoplasia and bacterial vaginosis: correlation or risk factor?

Bacterial Vaginosis (B.V.) is a syndrome defined microbiologically where lactobacilli-dominated flora is exchanged with an abundant complex flora dominated by strict and facultative anaerobic bacteria, constituted by gardenerella, micrococci, streptococci and staphylocci. It has been suggested that B.V. could be important in the development of cervical intracpithelial neoplasias, because the abnormal micro flora can produce careinogenic nitrosamines. The aim of this investigation was to evaluate the correlation between CIN and B.V. in 1,008 patients (median age: 28 years, range 17-60) who were divided into two groups: the first group consisted of 504 patients affected by CIN of different degrees, the second of 504 patients without CIN. All patients were submitted to colposcopy, pap-tests, cytology of the cervical canal and microcolpohysteroscopy in the case of lesions invading the cervical canal. The diagnosis of B.V. is based on four criteria: presence of clue cells, pH 4.5, positive amine test and increased vaginal discharge. X2 Pearson analysis was applied for statistical evaluation of the data. Among the 504 patients in the first group (women affected by CIN of different degrees), 180/504 (36%) women presented B.V. Among the second group (504 women without CIN), 248/504 (49%) women presented B.V. The results of our study demonstrate that there is no significant correlation between CIN and B.V. In the first group of patients affected by CIN and B.V., B.V. was present in 36% of the cases, while in the second group of patients not affected by CIN. B.V. was present in 49% of the cases (P < 0.00005).