Open AccessUtility of the Rapid Antigen Detection Test E. histolytica Quik Chek for the Diagnosis of Entamoeba histolytica Infection in Nonendemic Situations
Author(s) -
Yasuaki Yanagawa,
Rieko Shimogawara,
Tomoyuki Endo,
Rika Fukushima,
Hiroyuki Gatanaga,
Kasumi Hayasaka,
Yoshimi Kikuchi,
Taiichiro Kobayashi,
Michiko Koga,
Tomohiko Koibuchi,
Toshikazu Miyagawa,
Ayaka Nagata,
Hirotomo Nakata,
Shinichi Oka,
Risa Otsuka,
Kazumi Sakai,
Mami Shibuya,
Hiroyuki Shingyochi,
Etsuko Tsuchihashi,
Kôji Watanabe,
Kenji Yagita
Publication year - 2020
Publication title -
journal of clinical microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.349
H-Index - 255
eISSN - 1070-633X
pISSN - 0095-1137
DOI - 10.1128/jcm.01991-20
Subject(s) - entamoeba histolytica , antigen , parasite hosting , virology , diagnostic test , medicine , immunology , biology , microbiology and biotechnology , pediatrics , world wide web , computer science
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.