使用多个菌落挑取法对B族链球菌多种血清型的阴道和直肠定植情况进行特征分析。

Characterization of vaginal & rectal colonization with multiple serotypes of group B streptococci using multiple colony picks.

作者信息

Ferrieri P, Hillier S L, Krohn M A, Moore D, Paoletti L C, Flores A E

机构信息

University of Minnesota Medical School, Minneapolis, MN, USA.

出版信息

Indian J Med Res. 2004 May;119 Suppl:208-12.

PMID:15232197

Abstract

BACKGROUND & OBJECTIVES: There is paucity of information on vaginal and rectal colonization with multiple serotypes of group B streptococci (GBS). As part of an ongoing cohort study evaluating the natural history of vaginal and rectal colonization by GBS, the colonization with multiple serotypes was studied in 102 non-pregnant women aged 18-30 yr.

METHODS

Up to ten separate colony picks of beta-haemolytic streptococci (total 1515 isolates) were selected from vaginal and rectal primary culture plates. The colonies were identified as GBS, and their capsular polysaccharides (CPS) serotypes determined using monospecific rabbit antisera for types Ia-VIII by double immunodiffusion in agarose (DID). A colony dot immunoblot (DB) assay, using monospecific rabbit antisera to purified type polysaccharides conjugated to tetanus toxoid, was developed to serotype efficiently the multiple colony picks of GBS.

RESULTS

The CPS serotype distribution, examining only the 177 "a" or first colony picks from the 102 patients, was 30.5 per cent for Ia; 28.2 per cent for type III; 15.3 per cent for type II; and 13.6 per cent for type V. Only 2.8 per cent were nontypeable. Eighty of the 102 patients (78.4%) were colonized with only one serotype; 20 (19.6%) had two serotypes and two patients (2%) had three serotypes in their vaginal and/or rectal paired cultures. Overall, 91.9 per cent of the culture sites colonized with one to three CPS types (from the total number of colonies picked) were identified with a minimum of three colony picks. In 75 patients with vaginal/rectal pairs the GBS serotype concordance of only the "a" colony was 89.3 per cent and concordance decreased to 80 per cent when the serotype concordance of the total colony picks was analyzed.

INTERPRETATION & CONCLUSION: In conclusion, there was a relatively high prevalence of serotype nonconcordance in this population, and 21.6 per cent of patients had multiple GBS serotypes.

摘要

背景与目的

关于B族链球菌（GBS）多种血清型在阴道和直肠定植的信息较少。作为一项正在进行的评估GBS阴道和直肠定植自然史的队列研究的一部分，对102名年龄在18至30岁的非孕妇的多种血清型定植情况进行了研究。

方法

从阴道和直肠原代培养平板中选取多达十个不同的β溶血性链球菌菌落（共1515株分离株）。将菌落鉴定为GBS，并使用针对Ia - VIII型的单特异性兔抗血清，通过琼脂糖双免疫扩散（DID）法测定其荚膜多糖（CPS）血清型。开发了一种菌落斑点免疫印迹（DB）检测方法，使用针对与破伤风类毒素偶联的纯化型多糖的单特异性兔抗血清，对GBS的多个菌落进行高效血清分型。

结果

仅检查102例患者的177个“a”或首个菌落，CPS血清型分布为：Ia型占30.5%；III型占28.2%；II型占15.3%；V型占13.6%。仅2.8%为不可分型。102例患者中有80例（78.4%）仅被一种血清型定植；20例（19.6%）有两种血清型，2例患者（2%）在阴道和/或直肠配对培养中有三种血清型。总体而言，从挑选的菌落总数来看，91.9%的被一至三种CPS类型定植的培养部位，通过至少三次菌落挑选得以鉴定。在75例有阴道/直肠配对样本的患者中，仅“a”菌落的GBS血清型一致性为89.3%，分析所有菌落挑选的血清型一致性时，一致性降至80%。