[Development and application of rapid molecular method for detection of asymptomatic infection of Leishmania].

Objective: To develop a rapid molecular biological method for detection of the asymptomatic infection of Leishmania.
Methods: Two pairs of primers named RV1-RV2 and K13A-K13B were selected to be the fast diagnosis primers since they were designed according to the conserved region of Leishmania kinetoplast DNA (kDNA) minicircles. The PCR amplification products of Leishmania donovani promastigote from Shandong Province were sequenced to compare their conservatism. The method was applied to detect 105 venous blood samples from healthy home canine and 7 venous blood samples from home canine suffered from Kala-azar in Heishui County of Sichuan Province, and 75 venous blood samples from susceptible population (no leishmaniasis symptoms) and 7 venous blood samples from patients in Xinjiang Kashi area in order to verify the feasibility and accuracy of the method.
Results: The size of PCR products was consistent with the expected fragments with high conservative among Leishmania species. The positive rates of 105 home canine samples and 75 susceptible population samples were 37.14% (39/105) and 82.67% (62/75) rspectively, and the positive rates of home canine suffered from Kala-azar and patients were all 100%(7/7).
Conclusion: This rapid diagnosis method is suitable for detection of asymptomatic infection of Leishmania in Kalaazar endemic areas of China with high sensitive and specific, thus it has bright perspective to be used.