Relation between endemic (Balkan) nephropathy and urinary-tract tumours.

Serum and urine beta 2-microglobulin concentrations were determined in 38-6% of the 869 inhabitants of a village in which both Balkan endemic nephropathy and papillary tumours of the urinary-tract epithelium are common. Over 23% of the "healthy" population had raised serum and/or urine beta 2-microglobulin. 5 of 6 patients with papillary tumours of the renal pelvis, without evidence of renal parenchymal involvement, and 13-4% of the "healthy" population had raised serum-beta 2-microglobulin. It is suggested that overproduction of beta 2-microglobulin, a light-chain-like immune globulin, by the tumour cells may result in a light-chain-like nephropathy--i.e., endemic Balkan nephropathy.