Hcp1-Based Rapid Immunochromatography Test Offers Improved Point-of-Care Diagnosis of Melioidosis
Researchers developed and validated a rapid immunochromatography test targeting hemolysin-coregulated protein 1 (Hcp1) for serological diagnosis of melioidosis across 487 culture-confirmed patients in Thailand. The Hcp1-ICT achieved 88.3% sensitivity and 92.4% agreement with ELISA, substantially outperforming the current indirect haemagglutination assay (69.5% sensitivity, 67.6% specificity) and offering a viable point-of-care alternative for resource-limited settings.
The original study
A Rapid Immunochromatography Test Based on Hcp1 Is a Potential Point-of-Care Test for Serological Diagnosis of Melioidosis.
- Authors
- Phokrai P, Karoonboonyanan W, Thanapattarapairoj N, Promkong C, Dulsuk A, Koosakulnirand S, et al.
- Journal
- Journal of clinical microbiology
- Type
- Comparative Study, Evaluation Study, Journal Article, Multicenter Study, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't
- PMID
- 29848565
Original abstract
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.