Goel Neeraj, Wattal Chand, Gujral Kanwal, Dhaduk Nehal, Mansukhani Chandra, Garg Pankaj
Department of Clinical Microbiology and Immunology, Sir Ganga Ram Hospital, New Delhi, India.
Institute of Obstetrics and Gynaecology, Sir Ganga Ram Hospital, New Delhi, India.
Indian J Med Microbiol. 2020 Jul-Dec;38(3 & 4):357-361. doi: 10.4103/ijmm.IJMM_20_333.
To study the prevalence of group B streptococci (GBS) in Indian pregnant women and associated risk factors.
Four hundred and fifty pregnant women attending antenatal outpatient/inpatient department between 35-38 weeks of gestation were enrolled in the study. All enrolled subjects were assessed by a predefined proforma for their demographics, socio-economic characteristics, education, toilet habits, obstetric history and clinical outcome. Two cotton swabs each from lower vagina and rectum were collected and plated on selective solid media CHROM agar Strept B (CHROMagarTM) and selective Enrichment Broth LIM RambaQUICK StreptB broth (CHROMagarTM). Presumptive identification of GBS was growth of 1-3 mm grayish white β-hemolytic colonies on BAP or mauve coloured colonies on CHROM agar Strept B. All presumptively identified GBS were confirmed as group B streptococcus by automated identification system-Vitek MS (Bio Merieux).
The recto vaginal colonization rate of GBS in this study was observed as 3.3% (n=15). GBS colonization was significantly associated with nulliparous women (p= 0.026) and use of western style toilet (p=0.017). GBS urinary tract infections was also seen more commonly in women with GBS rectovaginal colonization (p=0.002).
Due to the low GBS prevalence and no significant association with major risk factors, we recommend to institute universal screening of GBS in pregnant women, instead of risk based screening. Since this was a single centric study with low prevalence of GBS, its applicability may be limited, therefore further larger multi-centric prospective studies are required to understand the true GBS prevalence in Indian society.
研究印度孕妇中B族链球菌（GBS）的流行情况及相关危险因素。
选取450名妊娠35 - 38周期间到产前门诊/住院部就诊的孕妇纳入研究。所有纳入的受试者均通过预定义的表格评估其人口统计学、社会经济特征、教育程度、如厕习惯、产科病史和临床结局。分别从阴道下段和直肠采集两根棉拭子，接种于选择性固体培养基CHROM琼脂链球菌B（CHROMagarTM）和选择性增菌肉汤LIM RambaQUICK链球菌B肉汤（CHROMagarTM）。GBS的初步鉴定为在血平板上生长1 - 3毫米灰白色β溶血菌落或在CHROM琼脂链球菌B上生长淡紫色菌落。所有初步鉴定为GBS的菌株均通过自动鉴定系统Vitek MS（生物梅里埃公司）确认为B族链球菌。
本研究中GBS的直肠阴道定植率为3.3%（n = 15）。GBS定植与初产妇（p = 0.026）和使用西式马桶（p = 0.017）显著相关。GBS直肠阴道定植的女性中GBS尿路感染也更常见（p = 0.002）。
由于GBS流行率低且与主要危险因素无显著关联，我们建议对孕妇进行GBS普遍筛查，而非基于风险的筛查。由于这是一项GBS流行率低的单中心研究，其适用性可能有限，因此需要进一步开展更大规模的多中心前瞻性研究，以了解印度社会GBS的真实流行情况。
