Comparison of qPCR and chromogenic culture methods for rapid detection of group B streptococcus colonization in Vietnamese pregnant women

IF 1.7 Q3 MEDICAL LABORATORY TECHNOLOGY

Practical Laboratory Medicine Pub Date : 2024-10-15 DOI:10.1016/j.plabm.2024.e00435

Manh-Tuan Ha , Huyen Tran-Thi-Bich , Thao Bui-Thi-Kim , My-Linh Nguyen-Thi , Thanh Vu-Tri , Thuy-Duong Ho-Huynh , Tuan-Anh Nguyen

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引用次数: 0

Abstract

Introduction

Neonatal infections can rapidly become severe, with delays in treatment often proving fatal. Streptococcus agalactiae (Group B Streptococcus, GBS) is a common cause, typically transmitted from colonized pregnant women to neonates during childbirth. In Vietnam, routine prenatal care lacks standardized GBS screening protocols. This study aims to compare enhanced qPCR methods with the culture method, evaluate the diagnostic accuracy of these qPCR procedures, and assess the frequency of GBS infection in pregnant Vietnamese women during their final trimester.

Materials and methods

Pregnant women aged 35 weeks gestation or more were recruited. Rectovaginal swabs were collected and analyzed for GBS using chromogenic culture, a commercial real-time PCR kit, and in-house real-time PCR assays targeting the cfb and sip genes. Clinical diagnostic values were calculated, and GBS prevalence was determined.

Results

The study included 259 pregnant women with a mean age of 30.2 ± 5.0 years. Of these, 96.6 % had gestational ages of 37 weeks or more at delivery. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the cfb-based and sip-based qPCR assays were 94.1/92.7, 99.0/99.5, 97.1/98.5, 97.8/97.3, and 97.6 %, respectively. The Kappa values were excellent (0.940 and 0.939), with results available in under 2 h. GBS prevalence was 24.7 % and 25.5 % by cfb-based and sip-based qPCR assays, aligning with the culture method (25.5 %).

Conclusions

Both direct real-time PCR assays demonstrated high accuracy and were comparable to chromogenic culture in diagnosing GBS. A significant prevalence of GBS colonization was found among Vietnamese pregnant women in their final trimester.

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比较 qPCR 和色原培养法快速检测越南孕妇 B 群链球菌定植情况

导言：新生儿感染会迅速恶化，延误治疗往往会导致死亡。无乳链球菌（B 组链球菌，GBS）是一种常见的致病菌，通常在分娩过程中由带有菌落的孕妇传染给新生儿。在越南，常规产前护理缺乏标准化的 GBS 筛查方案。本研究旨在比较增强型 qPCR 方法和培养方法，评估这些 qPCR 程序的诊断准确性，并评估越南孕妇在最后三个月感染 GBS 的频率。收集直肠阴道拭子，并使用色原培养法、商用实时 PCR 试剂盒和针对 cfb 和 sip 基因的内部实时 PCR 检测法进行 GBS 分析。计算了临床诊断值，并确定了 GBS 患病率。其中，96.6%的孕妇分娩时胎龄为 37 周或以上。基于 cfb 和基于 sip 的 qPCR 检测的灵敏度、特异性、阳性预测值、阴性预测值和准确性分别为 94.1/92.7、99.0/99.5、97.1/98.5、97.8/97.3 和 97.6%。基于 cfb 和基于 sip 的 qPCR 检测方法的 GBS 感染率分别为 24.7% 和 25.5%，与培养方法（25.5%）一致。结论两种直接实时 PCR 检测方法在诊断 GBS 方面都具有很高的准确性，与色原培养法不相上下。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Practical Laboratory Medicine Health Professions-Radiological and Ultrasound Technology

CiteScore

3.50

自引率

0.00%

发文量

审稿时长

7 weeks

期刊介绍： Practical Laboratory Medicine is a high-quality, peer-reviewed, international open-access journal publishing original research, new methods and critical evaluations, case reports and short papers in the fields of clinical chemistry and laboratory medicine. The objective of the journal is to provide practical information of immediate relevance to workers in clinical laboratories. The primary scope of the journal covers clinical chemistry, hematology, molecular biology and genetics relevant to laboratory medicine, microbiology, immunology, therapeutic drug monitoring and toxicology, laboratory management and informatics. We welcome papers which describe critical evaluations of biomarkers and their role in the diagnosis and treatment of clinically significant disease, validation of commercial and in-house IVD methods, method comparisons, interference reports, the development of new reagents and reference materials, reference range studies and regulatory compliance reports. Manuscripts describing the development of new methods applicable to laboratory medicine (including point-of-care testing) are particularly encouraged, even if preliminary or small scale.