[Endemic Balkan nephropathy (author's transl)].

Endemic Balkan nephropathy (EBN) is a chronic interstitial nephritis which may occur at any age and may affect several members of the same family. The condition is slowly progressive and can more easily be diagnosed in its advanced than in its early stages. Early symptoms include severe anaemia and increased plasma aminoacids, alkaline phosphatases and gamma 2 and alpha globulins. Eosinophilia is not uncommon. Loss of urine concentration power and high beta 2 microglobin urinary levels are among the earliest signs of EBN and of considerable diagnostic value. Renal biopsy shows invasive sclerosis, IgG and IgA deposits in glomerular vessels and Bowman's capsule walls and, characteristically, osmiophilic granulations within the mitochondria of proximal tubule cells; the mitochondria may in due course burst and disappear. Atrophic or dystrophic changes may develop in the stomach, upper intestine and liver. The aetiology of EBN remains undetermined, but chronic intoxication with drinking water polluted by silicates released during soil erosion seems to be the most probable cause. Silicates may act directly or by inducing an immune process.