Renal sequelae to nephropathia epidemica.

Clinical data and renal biopsy findings were studied in 9 patients 4-5 years after the acute phase of Nephropathia epidemica. Laboratory data suggested slightly depressed tubular function, but glomerular function was normal. Light microscopy of renal biopsy specimens showed slight residual interstitial fibrosis and occasionally atrophic tubuli, tubular casts, increased number of hyalinized glomeruli, and minor changes in other glomeruli. Two specimens showed fibrotic scars in the cortex. Electron microscopy revealed degenerative changes in the glomeruli, arterioles and tubules. The immunohistochemical study showed no fixed immunoglobulins in the kidney. The study shows that practically complete and lasting clinical recovery follows the acute phase of Nephropathia epidemica and that the disease does not leave diagnostic structural changes in the kidneys.