Development and initial evaluation of a lateral flow dipstick test for antigen detection of Entamoeba histolytica in stool sample

作者:Saidin Syazwan; Yunus Muhammad Hafiznur; Othman Nurulhasanah; Lim Yvonne Ai Lian; Mohamed Zeehaida; Zakaria Nik Zairi; Noordin Rahmah*
来源:Pathogens and Global Health, 2017, 111(3): 128-136.
DOI:10.1080/20477724.2017.1300421

摘要

Entamoeba histolytica infection remains a public health concern in developing countries. Early diagnosis of amoebiasis can avoid disease complications, thus this study was aimed at developing a test that can rapidly detect the parasite antigens in stool samples. Rabbits were individually immunized with recombinant pyruvate phosphate dikinase (rPPDK) and E. histolytica excretory-secretory antigens to produce polyclonal antibodies. A rapid dipstick test was produced using anti-rPPDK PAb lined on the dipstick as capture reagent and anti-EhESA PAb conjugated to colloidal gold as the detector reagent. Using E. histolytica-spiked in stool sample of a healthy individual, the detection limit of the dipstick test was found to be 1000 cellsml(-1). Meanwhile when rPPDK was spiked in the stool sample, the minimum concentration detected by the dipstick test was 0.1gml(-1). The performances of the dipstick, commercial Techlab E. histolytica II enzyme-linked immunosorbent assays (ELISA) and real-time PCR were compared using 70 stool samples from patients infected with Entamoeba species (n=45) and other intestinal pathogens (n=25). When compared to real-time PCR, the diagnostic sensitivity of the dipstick for detection of E. histolytica was 65.4% (n=17/26); while the diagnostic specificity when tested with stool samples containing other intestinal pathogens was 92% (23/25). In contrast, Techlab E. histolytica II ELISA detected 19.2% (5/26) of the E. histolytica-positive samples as compared to real-time PCR. The lateral flow dipstick test produced in this study enabled rapid detection of E. histolytica, thus it showed good potential to be further developed into a diagnostic tool for intestinal amoebiasis.

  • 出版日期2017