Xanthogranulomatous pyelonephritis (XGP): a local disease with systemic manifestations. Report of 23 patients and review of the literature

The clinical, pathological and radiographic findings of 135 cases of xanthogranulomatous pyelonephritis have been reviewed. It is a form of renal suppuration and obstruction most commonly seen in middle aged women although all ages and both sexes may be affected. There is no race predilection. Gram-negative organisms are usually present and bilateral involvement has not been reported. The most common offending organism is Proteus mirabilis. Hepatic dysfunction is seen and appears to normalize with removal of the XGP process. Preoperative angiography may increase the accuracy of differentiating this disorder from hypernephroma and may aid the surgeon in planning his approach to kidney resection depending upon the staging of XGP. Chronic renal failure is not usually a feature of XGP and nephrectomy is curative without any incidence of recurrence.