Abstract:

AIM:To evaluate the diagnostic value of rK39,a recombinant antigen,in visceral leishmaniasis. METHOD:Using a recombinant product with 39 amino acid repeats found in a kinesin like gene of visceral leishmania spp.rK39,as antigen in ELISA for immunodiagnosis,sera of 107 kala azar cases from Xinjiang,Gansu and Sichuan were assayed.RESULTS:Of 107 visceral leishmaniasis cases,103 were seropositive(96.2%) at a serum titre of 1∶100 with 80 ng of rK39. Of 65 cases under five years of age, 62(95.3%) were found seropositive.Thirty one samples with an OD 1.0 for the anti rK39 antibodies were subjected to end point titration,the distribution of their titres ranged from 1∶1 000 to 1∶12 800.Except for one leprosy patient with an OD of 0.43,no cross reaction was found for sera from malaria,tuberculosis and schistosomiasis patients or sera from healthy control.CONCNUSION:This is for the first time to use a recombinant antigen in the diagnosia of leishmaniasis in China.The results indicate that it is a specific and sensitive method for serodiagmosis of the disease.