[The pathomorphology and pathogenesis of lithium-induced nephropathy]

Results are submitted for a morphologic study of two nephrobiopsies in patients with manic-depressive psychosis on long-term treatment with lithium drugs, who developed clinical symptoms of chronic renal insufficiency. Light-optic, electronic-, and immunofluorescent microscopy was made use of in the study. Both biopsies showed features consistent with the diagnosis of chronic interstitial nephritis with manifest changes in proximal convoluted tubules of the kidney. On the basis of the morphologic picture of the kidney lesion and chemical nature of lithium (metal of the group and ionic identity with sodium and potassium) a conclusion was drawn that the initial mechanism in the development of renal pathology in exposure to lithium is a damage to the proximal convoluted tubules.