Entamoeba histolytica infection is an increasingly common sexually transmitted infection in Japan. Currently, stool ova and parasite examination (O&P) is the only approved diagnostic method. Here, we assessed the utility of the commercially available rapid antigen detection test (Quik Chek) for E. histolytica. A multicenter cross-sectional study was conducted. Stool samples that had been submitted for O&P were included. The samples were subjected to both Quik Chek and PCR, and the Quik Chek results were assessed in comparison with PCR as the reference standard. E. histolytica infection was confirmed in 5.8% (38/657) of the samples and comprised 20 diarrheal and 18 nondiarrheal cases. The overall sensitivity and specificity of Quik Chek were 44.7% (95% confidence interval, 30.1 to 60.3) and 99.8% (99.1 to 100), respectively. The sensitivity of Quik Chek was higher for diarrheal cases (60.0%) than for nondiarrheal cases (27.8%). Furthermore, the combined use of Quik Chek with O&P increased the sensitivity (78.9%), especially for diarrheal cases (up to 90%). The E. histolytica burden assessed by quantitative PCR was similar between Quik Chek-positive and -negative samples. The Quik Chek assay sensitivity was lower for cyst-containing stools than for trophozoite-containing stools, although it was shown that cultured E. histolytica clinical strains from Quik Chek-negative cyst-containing stools exhibited antigenicity in vitro. The present study confirmed the high specificity of Quik Chek for E. histolytica infection. Combined use with O&P increased the sensitivity of detection, facilitating the use of Quik Chek in point-of-care settings in nonendemic situations.

中文翻译：

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快速抗原检测测试E. HISTOLYTICA QUIK CHEK在非流行情况下用于诊断溶组织性变形杆菌的用途。

在日本，溶组织性变形杆菌的感染是一种越来越普遍的性传播感染。目前，粪便卵和寄生虫检查（O＆P）是唯一批准的诊断方法。在这里，我们评估了商业可用的快速抗原检测试验（Quik Chek）对溶组织性大肠杆菌的实用性。进行了多中心横截面研究。包括已提交给O＆P的粪便样本。对样品进行Quik Chek和PCR检验，并与PCR作为参考标准进行比较，评估Quik Chek结果。溶组织性大肠杆菌在5.8％（38/657）的样本中证实感染，包括20例腹泻和18例非腹泻病例。Quik Chek的总体敏感性和特异性分别为44.7％（95％置信区间，30.1至60.3）和99.8％（99.1至100）。腹泻病例的Quik Chek敏感性较高（60.0％），非腹泻病例的敏感性较高（27.8％）。此外，Quik Chek与O＆P的组合使用可提高敏感性（78.9％），尤其是对于腹泻病例（高达90％）。的溶组织内阿米巴通过定量PCR评估负担Quik的赤阳性和阴性样品之间相似。尽管已证明培养的溶组织性大肠杆菌能对含囊粪的粪便进行Quik Chek测定的敏感性低于对含滋养体的粪便。Quik Chek阴性囊肿粪便的临床菌株在体外表现出抗原性。本研究证实了Quik Chek对溶组织性大肠杆菌的高度特异性。将O＆P与O＆P结合使用可提高检测的敏感性，从而有助于在非流行情况下在护理点中使用Quik Chek。