Xanthogranulomatous pyelonephritis: a review

Xanthogranulomatous pyelonephritis (XP), first described in 1916, is a rare form of chronic granulomatous inflammation. The etiology is still unclear; however, the development of the disease is associated with chronic urinary obstruction secondary to lithiasis, tumors and urological malformations, among others. This leads to the destruction of the renal parenchyma and its replacement by solid sheets of lipid-laden macrophages. Female gender, diabetes and obesity are attributed as predisposing factors to the development of XP. It is estimated that the incidence presents a maximum peak between 50 and 70 years, with a ratio of 2:1 women-men respectively. Computed tomography (CT) is described as the mainstay in the evaluation. However, the definitive diagnosis is made by histopathological study, where a mixture of lipid-laden foamy macrophages, lymphocytes, neutrophils, giant cells, and plasma cells can be seen. Nephrectomy (open or laparoscopic) continues to be the first-line treatment. The laparoscopic approach is associated with an increase in operating time; however, the recovery time is shorter compared to the open approach. Given the natural history of the disease and the associated complications, this makes it a challenging approach for the surgeon. Therefore, a surgeon experienced in laparoscopic skills is necessary. This review seeks to synthesize existing information regarding the appropriate surgical approach in conjunction with the clinical context.