Danubian endemic familial nephropathy

Danubian endemic familial nephropathy (DEFN), sometimes called Balkan endemic nephropathy, is a form of interstitial nephritis. It was first identified in the 1920s among several small, discrete communities along the Danube River and its major tributaries, in the modern countries of Croatia, Bosnia, Serbia, Romania and Bulgaria.

A striking feature of the disease is its very localized occurrence. There are approximately ten small areas where it occurs, all of them more or less rural, but nothing seems to connect those areas other than the occurrence of this illness.

Causes
The etiology for DEFN is currently unknown. . It has recently been hypothesized that chronic exposure to dietary aristolochic acid is a major risk for DEFN. Aristolochic acid may come from Aristolochia clematitis, a plant native to the endemic region, and its seeds may comingle with wheat used for bread. This theory has recently gained further support through research by Arthur P. Grollman, cancer biologist and the director of Stony Brook University's chemical biology lab in New York, and Bojan Jelaković, an associate professor at the Zagreb University School of Medicine.