Retro-peritoneal fibrosis: A rare presentation with localized unilateral perirenal fibrosis

We report a rare case of localized unilateral perirenal involvement in retroperitoneal fibrosis in a man presenting with left upper abdominal discomfort and generalized weakness. The increased diagnostic capabilities and imaging characteristics of computed tomography and magnetic resonance imaging are emphasized. Multiple tissue sampling for histopathological study should be done to rule out malignancy in cases of atypical site involvement