Prevalencia de portación de Estreptococo Grupo B (EGB) en embarazadas y comparación de la microbiota vaginal de gestantes colonizadas y no colonizadas en un hospital universitario

Introduction. The colonization by GBS during pregnancy is of particular importance because of the possibility of vertical transmission which in the absence of prevention, causes neonatal sepsis and meningitis.Objective. To study the prevalence of carriage of GBS in pregnant women in two periods, comparing the vaginal microbiota between colonized pregnant and non-colonized pregnant women.Materials and methods. The carriage of GBS (weeks of gestation: 32-37) in 866 patients who prospectively and consecutively attended the hospital during two periods (307 in 2010 and 559 in 2011 and 2012), was studied. A clinical examination and anorectal swabbing/vaginal introito (cultured in selected medium for GBS and subcultured in Columbia 5% blood agar base) during the first period and in STRB chromogenic agar during the second, were performed. The vaginal microbiological content was also analyzed by conventional methodology and Trichomonas vaginalis was investigated by modified thioglycolate medium. Statistical analysis: Chi-Square test (2) and Fischer.Results. Out of 307 pregnant women, 30 (9.8%) resulted colonized by GBS in 2010 and 81 out of 559 (14.5%) in 2011 and 2012. A higher prevalence of pathogenic flora was observed (51/111) (45.9%) in colonized pregnant women with respect to non – colonized ones (259/755) (34.3%) (2 yates: 5.21 p < 0.02). Candida spp was most frequently associated with colonized patients (36.9% vs 21.3%) (2 yates: 12.33; p < 0,0001), corresponding 23.4% to asymptomatic patients and 13.5% to symptomatic ones (2 yates: 5.97; p: 0.01).