基于艰难梭菌tcdC基因的新型LAMP检测方法的研发及临床诊断效能评估

Development and clinical diagnostic efficacy of a novel LAMP method targeting the tcdC gene in Clostridioides difficile

摘要:

目的 研发一项快速鉴定艰难梭菌并能明确高产毒株的检测方法,开展临床评估。方法 利用环介导等温扩增(LAMP)法,基于tcdC、tcdA、tcdB 基因来鉴定艰难梭菌,并评估该检测技术的灵敏度、特异度和总体一致性。结果 共完成499例疑似艰难梭菌感染腹泻住院患者粪便标本检测,艰难梭菌检出率为12.8%(64/499),其中产毒艰难梭菌的检出率为10.8%(54/499)。本检测方法针对tcdA的灵敏度为87.2%,特异度为98.9%,阳性预测值为89.1%, 阴性预测值为98.6%;对tcdB的灵敏度为88.2%,特异度为99.6%,阳性预测值为90.0%,阴性预测值为98.7%。不同菌株总毒素量各有不同,但A+B+菌株平均产毒量(1.79 μg/mL)高于A-B+菌株(0.72 μg/mL) 和A-B-菌株(<0.10 μg/mL)。结论 本便携式高通量LAMP检测方法能快速、高效鉴定艰难梭菌并且明确高毒株。

Abstract:

Objective To develop a method for rapidly identifying Clostridioides difficile (C. difficile) and determining high-producing toxin strains, conduct clinical evaluation. Methods The loop-mediated isothermal amplification (LAMP) method was used to identify C. difficile based on the tcdC, tcdA, and tcdB genes. The sensitivity, specificity, and overall consistency of the detection method were evaluated. Results Feces specimens from 499 hospitalized patients suspected of C. difficile-associated diarrhea were detected, with C.difficile detection rate of 12.8% (64/499), out of which the detection rate of toxin-producing C. difficile was 10.8% (54/499). The sensitivity, specificity, positive predictive value, and negative predictive value of the detection method for tcdA were 87.2%, 98.9%, 89.1%, and 98.6%, respectively, and 88.2%, 99.6%, 90.0%, and 98.73% for tcdB , respectively. The total toxin levels of different strains were different, but the average toxin production level of A+B+ strains (1.79 μg/mL) was higher than those of A-B+ strains (0.72 μg/mL) and A-B- strains (<0.10 μg/mL). Conclusion The portable high-throughput LAMP detection method can rapidly and efficiently identify C. difficile and determine high-producing toxin strains.