Balkanic Nephropathy (BN) is characterized by: an incidence limited to a geographic area: a familial character and a slow progressive evoluation towards chronic renal failure associated with the symmetrical reduction of the kidney size. The etiology of BN is unknown.The aim of our study was to find out the immune alterations in BN pathology.In the BN patients we identified a novel subset of the CD3+CD 16+CD56+T cells expressing the phenotypic characteristics of both T lymphocytes and NK cells. The analysis of various subpopulations of lymphocytes, however, showed no quantitative differences in comparison with healthy subjects and healthy subjects from the endemic area.