[Karyomegalic interstitial nephritis: an atypical case].

Karyomegalic interstitial nephritis (KIN) is a rare disease entity that was first described by Burry in 1974. The prevalence of this disease is less than 1% and its pathogenesis is unclear. KIN is characterized by chronic tubulointerstitial nephritis associated with enlarged tubular epithelial cell nuclei, which leads to progressive decline of renal function.