Karyomegalic tubulointerstitial nephritis: A rare cause of chronic kidney disease

Karyomegalic tubulointerstitial nephritis is a rare disease of uncertain etiology with typical clinical features of slowly progressive renal failure in the third decade of life. histological findings characterize striking enlarged and hyperchromic nuclei in nu- merous tubular epithelial cells throughout the nephron accompanied by interstitial fibrosis around atrophic tubules. herein, we report a case of 30 year-old patient who presented with asymptomatic progressive renal dysfunction in 2009. renal biopsy revealed chronic tubulointerstitial nephritis and an unusually marked karyomegaly particularly of the tubular epithelium.