孕晚期阴道B族链球菌定植的两种筛查方法比较

Comparison of Two Screening Methods of Virginal Group B Streptococcus Colonization in Late Pregnancy

目的比较传统阴道拭子培养法和阴道直肠拭子Lim次代接种法对孕晚期阴道B族链球菌(group B streptococcus,GBS)定植的筛查效果。方法 2014年12月至2015年8月在北京协和医院产科门诊接受常规产前检查的1371名孕妇,于孕35~37周同时采取传统阴道拭子培养法和阴道直肠拭子Lim次代接种法筛查GBS,采用卡方检验比较并分析两种筛查方法的阳性率、检出率和假阴性率。结果 1371名孕晚期妇女阴道GBS的定植率为8.0%,传统阴道拭子培养法的检出率为41.8%,假阴性率为58.2%;阴道直肠拭子的检出率为80.0%,假阴性率为20.0%;两种方法检出率差异具有统计学意义(P<0.001)。结论阴道直肠拭子Lim次代接种法对阴道GBS定植筛查的效率优于阴道拭子培养法,二者联合应用可提高检出率,避免漏诊。

Objective To compare the scanning efficiency between the traditional vaginal swab culture and Lim broth subinoculation culture using vaginal-rectal swab for group B Streptococcus（ GBS） colonization in late pregnancy. Methods A total of 1371 pregnant women who received prenatal care in Peking Union Medical College Hospital from December 2014 to August 2015 were enrolled in the study. Each patient got both kinds of culture in the 35 th to 37 th week of pregnancy. The positive rate,detection rate,and false negative rate of these two screening methods were compared and analyzed by chi-square test. Results The colonization rate of vaginal GBS in late pregnancy was 8. 0%. The detection rate of traditional vaginal swab culture was 41. 8% with a false negative rate of58. 2%,and the detection rate of vaginal-rectal swab culture was 80. 0% with a false negative rate of 20. 0%. The difference in the detection rate between these two methods was statistically significant（ P〈0. 01）. Conclusions The screening efficiency of Lim broth subinoculation culture using vaginal-rectal swab for GBS colonization in late pregnancy is superior to the traditional vaginal swab culture. Combined application of both methods might improve the detection rate and avoid the missed diagnosis.