Karyomegalic interstitial nephritis.

Karyomegalic interstitial nephritis is a singular type of progressive chronic interstitial nephritis. The pathogenesis of this disease is unknown. The present study reported the case of a 22-year-old man who presented with a long history of recurrent upper respiratory tract infection episodes secondary to bronchiectasis and with progressive renal failure. Renal biopsy revealed chronic tubulointerstitial nephritis and a surprisingly marked karyomegaly specifically of the tubular epithelium.