Study on producing a LAMP kit for diagnosis of small liver fluke Clonorchis sinensis infection in humans

Abstract

Background: Clonorchis sinensis is one of the three species of small liver flukes that cause infections in humans. C. sinensis is found mainly in several Asian countries and Northern, Vietnam. The Loop-mediated isothermal amplification (LAMP) with a sensitivity and specificity comparable to that of the PCR method, which requires less complex equipment and facilities for performance. Methods: The research design describes the laboratory experiment and evaluates a LAMP kit for the diagnosis of C. sinensis in the laboratory and the small-scale field assessment, using 150 human stool samples from fascioliasis endemic areas. Results: The LAMP primer sets have been designed and selected; the conditions and components of the LAMP reaction for C. sinensis diagnosis have been optimised. Evaluation results of the LAMP kit in the laboratory showed a sensitivity of the test was 98.63% (95% CI: 91.92-99.99%); a specificity was 100% (95% CI: 85.25-100%); the limit of detection was 26 gene copies/µl. The LAMP test kit was found to be stable within 12 months at -20±5^oC, and 6 months after opening the tubes. The field assessment of the LAMP
kit in Ninh Binh province showed a C. sinensis rate of 6.66%, which was similar to the rate obtained from the studies using the real-time PCR method. Conclusions: The research has successfully produced a LAMP kit for the diagnosis of C. sinensis that is sensitive >95% and highly specific >95%. The LAMP kit is stable within 12 months at -20±5^oC and for 6 months after opening the tubes.