Methods:1. The incidence of PKDL after treatment for VL will be investigated through studying a retrospective cohort which will be identified by cross-sectional survey; 2. serum level of cytokines and lipid profile will be measured respectively by cytometric bed-array and autoanalyzer before and after treatment for PKDL; 3. mRNA expression of cytokines will be measured real-time PCR before and after treatment for PKDL; 4. gene polymorphism will be investigated by DNA sequencing; 5. the new diagnostic tool will be developed using immunofluorescence technique; and, 6. urine antigens and antibodies will be detected by ELISA.