Using LDA test the presence of antibodies in patients prior to and post renal transplantation was studied. The relationship between the results of LDA test and graft rejection episodes, the treatment with large doses of prednisolone and CDC test performed simultaneously were analized. No correlation between results of LDA test prior to transplantation or its response to prednisolone treatment and acute rejection crises was found. The value of LDA test in predicting rejection episodes was not confirmed. LDA test detects antibodies 10 times more frequently than CDC test. The presence of cytotoxic antibodies CDC was not always connected with the presence of LDA and vice versa.