Novel multiplex real-time PCR assays reveal a high prevalence of diarrhoeagenic Escherichia coli pathotypes in healthy and diarrhoeal children in the south of Vietnam

BMC Microbiology

article

Duong, Vu Thuy¹  Vi, Lu Lan¹  Jenkins, Claire³  Okeke, Iruka⁴  Higginson, Ellen⁵  Baker, Stephen⁵  Tu, Le Thi Phuong¹  Tuyen, Ha Thanh¹  Nhi, Le Thi Quynh¹  Campbell, James I.¹  Van Minh, Pham¹  Le Phuc, Hoang²  Chau, Tran Thi Hong¹  Ngoc, Nguyen Minh⁷ 

[1] The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit;Children’s Hospital 1;National Infection Service, Public Health England;Department of Pharmaceutical Microbiology, Faculty of Pharmacy, University of Ibadan;Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID) Department of Medicine, Cambridge Biomedical Campus, University of Cambridge;University of Medicine and Pharmacy at Ho Chi Minh City;Children’s Hospital 2

关键词: ETEC;    EAEC;    EIEC;    EPEC;    EHEC;    Multiplex real-time PCR;    Diarrhoea children;    Healthy children;    Co-infection;   

DOI  :  10.1186/s12866-020-01878-5

学科分类：放射科、核医学、医学影像

来源: BioMed Central

【 摘 要 】

Diarrhoeagenic Escherichia coli (DEC) infections are common in children in low-middle income countries (LMICs). However, detecting the various DEC pathotypes is complex as they cannot be differentiated by classical microbiology. We developed four multiplex real-time PCR assays were to detect virulence markers of six DEC pathotypes; specificity was tested using DEC controls and other enteric pathogens. PCR amplicons from the six E. coli pathotypes were purified and amplified to be used to optimize PCR reactions and to calculate reproducibility. After validation, these assays were applied to clinical samples from healthy and diarrhoeal Vietnamese children and associated with clinical data. The multiplex real-time PCRs were found to be reproducible, and specific. At least one DEC variant was detected in 34.7% (978/2815) of the faecal samples from diarrhoeal children; EAEC, EIEC and atypical EPEC were most frequent Notably, 41.2% (205/498) of samples from non-diarrhoeal children was positive with a DEC pathotype. In this population, only EIEC, which was detected in 34.3% (99/289) of diarrhoeal samples vs. 0.8% (4/498) non-diarrhoeal samples (p < 0.001), was significantly associated with diarrhoea. Multiplex real-time PCR when applied to clinical samples is an efficient and high-throughput approach to DEC pathotypes. This approach revealed high carriage rates of DEC pathotypes among Vietnamese children. We describe a novel diagnostic approach for DEC, which provides baseline data for future surveillance studies assessing DEC burden in LMICs.

【 授权许可】

CC BY|CC0