Retroperitoneal fibrosis/periaortitis and hydronephrosis

Abstract

Retroperitoneal fibrosis/periaortitis is one of the major organ manifestations of immunoglobulin G4 (IgG4)-related disease (IgG4-RD). This complication of IgG4-RD can lead to renal insufficiency mediated by ureteral obstruction and hydronephrosis. The frequency of hydronephrosis or ureter obstruction has been reported to occur in up to two-thirds of patients with IgG4-related retroperitoneal fibrosis/periaortitis, and more than one half of patients with hydronephrosis or ureter obstruction suffered permanent renal injury (often end-stage renal disease). The location of the ureter obstructions and the lesions causing it vary widely in patients with hydronephrosis. Periaortic/periarterial lesions are the most frequent and cause renal insufficiency with a high probability when ureteral involvement is bilateral. Although the response to corticosteroid therapy is generally good, some cases are uncontrollable with corticosteroid alone and need an additional steroid-sparing immunosuppressive agent or urological intervention. Early detection of such conditions and the prompt initiation of appropriate treatment are necessary to improve the renal prognosis. Further studies are required to estimate the renal risk more accurately, to calculate the risk and benefit balance of corticosteroid therapy, to determine the efficacy of other treatment options, and to understand the most appropriate indications for urological intervention in hydronephrosis related to IgG4-related retroperitoneal fibrosis/periaortitis.