The study involved 17 patients on IPD. Blood serum levels of IgG, IgA, IgM, circulating immune complexes, complement and proteins were determinated at the beginning of therapy, after 3, 6, 12 months on IPD and after 1 year on hemodialysis. The frequency of peritonitis was noted during this time. Peritonitis was the most frequent during first 3 months on IPD. No differences in blood serum levels of IgG, IgA, IgM, in the specific periods of IPD were noted. A significant increase in blood serum circulating immune complexes in patients on IPD and hemodialysis compared to the control group was found. A significant decrease in blood serum of C3 complement in patients on IPD and hemodialysis in comparison with the controls were found. A significant decrease in blood serum proteins at the beginning of IPD and after 3 months IPD in comparison with proteins concentration in patients on hemodialysis was observed.