Epidemiological characteristics of Balkan endemic nephropathy in eastern regions of Yugoslavia.

Foci of Balkan endemic nephropathy have been found scattered along several rivers in many parts of Serbia, as well as in north-eastern Bosnia. There is no indication that the medical geography of the disease changes over time. As for the intensity of the endemic process, both the poor quality of the routinely collected data and an inconsistent methodological approach obscure the real epidemiological situation. The incidence of deaths, the most reliable measure of outcome, has been stable over the last few decades, slightly exceeding 3 per 1000 person-years of observation in the most heavily affected endemic villages. The point prevalence rate of hyper-beta-2-microglobulinuria, an indicator of tubular damage, also remained unchanged over that period, at a value as high as 20-25%. Over time, however, the course of the disease became more protracted and its onset moved towards older ages. These two facts may indicate a less intense contact with the agent(s) and, consequently, suggest a decreased burden of Balkan endemic nephropathy in the near future. The natural history of Balkan endemic nephropathy is still not well understood, however. The disease seems to have had an endemo-epidemic pattern in the past, and the possibility of another epidemic wave in the future cannot be completely ruled out.