Urinary creatinine excretion in children from families with Balkan endemic nephropathy: evidence for genetic predisposition to the disease.

Balkan endemic nephropathy (BEN) is a chronic tubulointerstitial kidney disease prevalent in Serbia, Bosnia, Croatia, Bulgaria and Romania. Genetic studies have supported the genetic predisposition to BEN, and some studies in Bulgaria and in the Kolubara region of Serbia have revealed abnormalities of the urinary tract in up to 46% of children from families with BEN. In the present study, urinary excretion of creatinine, an index of muscle mass, was studied in 703 healthy children from endemic and non-endemic areas around the South Morava River. The survey covered a three-year period, and the children were studied three times a year: in the spring, autumn and winter. A urine sample for the period corresponding to 7-10 a.m. was collected during each study period. Evidence has been presented that children from families with BEN excrete significantly less creatinine than those from families without BEN living in the same area, or than children living in villages outside the endemic region or in the city of Nis. This study supports the view that genetic predisposition to BEN is indicated by a smaller muscle mass, although the effect of living conditions and nutrition may also contribute to this.