A Rapid Immunochromatography Test Based on Hcp1 Is a Potential Point-of-Care Test for Serological Diagnosis of Melioidosis

• Published in: Journal of clinical microbiology Vol. 56; no. 8
• Main Authors: Phokrai, Phornpun, Karoonboonyanan, Wisansanee, Thanapattarapairoj, Nida, Promkong, Chidchanok, Dulsuk, Adul, Koosakulnirand, Sirikamon, Canovali, Sasha, Indrawattana, Nitaya, Jutrakul, Yaowaruk, Wuthiekanun, Vanaporn, Limmathurotsakul, Direk, Brett, Paul J., Burtnick, Mary N., Lertmemongkolchai, Ganjana, Chantratita, Narisara
• Format: Journal Article
• Language: English
• Published: United States American Society for Microbiology 01.08.2018
• Subjects: Immunoassays; immunochromatography test; rapid test; point-of-care test; Burkholderia pseudomallei; melioidosis; antibody detection; serological diagnosis
• ISSN: 0095-1137; 1098-660X; 1098-660X
• DOI: 10.1128/JCM.00346-18

Melioidosis is a fatal infectious disease caused by the environmental bacterium Burkholderia pseudomallei . It is highly endemic in Asia and northern Australia but neglected in many other tropical countries. Melioidosis is a fatal infectious disease caused by the environmental bacterium Burkholderia pseudomallei . It is highly endemic in Asia and northern Australia but neglected in many other tropical countries. Melioidosis patients have a wide range of clinical manifestations, and definitive diagnosis requires bacterial culture, which can be time-consuming. A reliable rapid serological tool is greatly needed for disease surveillance and diagnosis. We previously demonstrated by enzyme-linked immunosorbent assay (ELISA) that a hemolysin-coregulated protein (Hcp1) is a promising target for serodiagnosis of melioidosis. In this study, we developed a rapid immunochromatography test (ICT) using Hcp1 as the target antigen (Hcp1-ICT). We evaluated this test for specific antibody detection using serum samples obtained from 4 groups of human subjects, including the following: (i) 487 culture-confirmed melioidosis patients from four hospitals in northeast Thailand; (ii) 202 healthy donors from northeast Thailand; (iii) 90 U.S. healthy donors; and (iv) 207 patients infected with other organisms. Compared to culture results as a gold standard, the sensitivity of ICT for all hospitals was 88.3%. The specificities for Thai donors and U.S. donors were 86.1% and 100%, respectively, and the specificity for other infections was 91.8%. The results of the Hcp1-ICT demonstrated 92.4% agreement with the Hcp1-ELISA results with a kappa value of 0.829, indicating that the method is much improved compared with the current serological method, the indirect hemagglutination assay (IHA) (69.5% sensitivity and 67.6% specificity for Thais). The Hcp1-ICT represents a potential point-of-care (POC) test and may be used to replace the IHA for screening of melioidosis in hospitals as well as in resource-limited areas.