Retroperitoneal disorders associated with IgG4-related autoimmune pancreatitis.

IgG4-related autoimmune pancreatitis is frequently accompanied by relevant lesions in the genitourinary tract and retroperitoneal organs, which cause various clinical problems, ranging from non-specific back pain or bladder outlet obstruction to renal failure. The diagnosis of IgG4-related retroperitoneal fibrosis requires a multidisciplinary approach, including serological tests, histological examination, imaging analysis, and susceptibility to steroid therapy. Radiological examinations are helpful to diagnose this condition, but surgical resection is occasionally unavoidable to exclude malignancy, particularly for patients with isolated retroperitoneal involvement. Steroid therapy is the treatment of choice for this condition, the same as for other manifestations of IgG4-related disease. For patients with severe ureteral obstruction, additional ureteral stenting needs to be considered prior to steroid therapy to preserve the renal function. Some papers have suggested that IgG4-related disease can affect male reproductive organs including the prostate and testis. IgG4-related prostatitis usually causes lower urinary tract symptoms, such as dysuria and pollakisuria. Patients sometimes state that corticosteroids given for IgG4-related disease at other sites relieve their lower urinary tract symptoms, which leads us to suspect prostatic involvement in this condition. Because of the limited number of publications available, further studies are warranted to better characterize IgG4-related disease in male reproductive organs.