An etiological approach to Balkan endemic nephropathy based on the investigation of two genetically different populations.

The direct inheritance as a possible etiologic factor of Balkan endemic nephropathy (BEN) has been studied in an endemic area in the district of Slavonski Brod (Croatia-Yugoslavia). The basis for the investigation was given by a natural experiment induced by immigration of people from Ukraina to the endemic and nonendemic areas near Slavonski Brod. 1,536 persons in endemic villages and 733 inhabitants from the villages, where BEN has not been found, were studied with the aim of establishing diagnosis or excluding BEN. The generally adopted criteria enabling to classify the examined persons into the following 3 groups have been used: (a) diseased of BEN; (b) suspect to be diseased of BEN, and (c) individuals without signs of a renal disease. In the endemic villages among the population of Croatian aborigines, 12,1% diseased and suspects have been revealed. Among the Ukrainian immigrants and their offsprings, 10.5% diseased and suspects have been found. The difference is not significant (t = 0.7, p greater than 0.05). On the other hand, in nonendemic villages there were no diseased nor suspect BEN patients among the indigenous people as well as among the Ukrainians. The inference is suggested that the factors of the direct inheritance do not play a decisive role in the etiopathogenesis of BEN.