IgG4-related prostatitis manifesting as urinary obstruction in a 28-year-old male

Abstract

Background Immunoglobulin G4-related disease (IgG4-RD) is a systemic lymphoproliferative disorder characterized by elevated serum IgG4 levels and tumefactive lesions that can involve nearly every organ system. Involvement of the prostate is rare but has been reported in limited cases. Case presentation A 28-year-old man of Asian descent with a history of sinusitis and priapism presented to hospital with rigors and voiding symptoms. He was diagnosed with IgG4-RD one month prior to presentation, following pathological analysis of a submandibular mass that demonstrated chronic sclerosing sialadenitis. On presentation, white blood cell count, C-reactive protein, and prostate serum antigen levels were all within normal limits. Examination was notable for a large, firm prostate, and a foley catheter was inserted. Contrast CT of the abdomen was unremarkable. Further workup revealed elevated serum IgG4 levels (9.22 g/L) and he was subsequently started on prednisone 35 mg daily. Imaging to screen for systemic IgG4-RD involvement demonstrated paravertebral soft tissue involvement and he was given rituximab 1000 mg IV × 2 doses. MRI revealed diffuse prostatitis. Five days after starting prednisone and one day after his first dose of rituximab, he successfully passed trial of void and was discharged home. Conclusions IgG4-related prostatitis is a rare and underrecognized manifestation of IgG4-RD. Our case highlights the need to consider IgG4-related prostatitis as an etiology of urinary obstruction in young individuals. Resolution of symptoms following treatment with steroids may be diagnostic of IgG4-related prostatitis, and may potentially avoid the need for invasive diagnostic procedures such as prostate biopsy.

Imaging findings in inflammatory disease of the genital organs

“…Prostatic involvement in IgG4-related disease has been also reported, and in most cases described in the literature, patients were retrospectively diagnosed with IgG4-related prostatitis based on histopathological findings following transurethral resection for symptoms of benign prostatic hyperplasia. A presumptive diagnosis is often made when symptomatic relief of benign prostatic hyperplasia is observed after glucocorticoid treatment [ 40 , 41 ]. CT findings typically show diffuse enlargement of the prostate gland with homogeneous low attenuation, or the presence of nodular lesions within the prostate gland, with or without periprostatic soft-tissue infiltration [ 40 , 41 ] (Fig.…”

“…A presumptive diagnosis is often made when symptomatic relief of benign prostatic hyperplasia is observed after glucocorticoid treatment [ 40 , 41 ]. CT findings typically show diffuse enlargement of the prostate gland with homogeneous low attenuation, or the presence of nodular lesions within the prostate gland, with or without periprostatic soft-tissue infiltration [ 40 , 41 ] (Fig. 19 ).…”

“…19 ). PET imaging has also been used to support the diagnosis of IgG4-related prostatitis [ 41 ], showing an inverted V-shaped increase in FDG uptake in the prostate [ 42 ].

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IgG4-Related Prostatitis: A Potentially Underappreciated Finding for Pathologists

“…IgG4-related disease (IgG4-RD) is an autoimmune-mediated disease that can effectively involve every organ system, with limited data on genitourinary tract involvement. [1][2][3][4][5][6][7] Detailed findings of IgG4-RD involving the prostate consist of mostly single case reports, with the largest known study of histologically confirmed prostatic involvement by IgG4-RD including 9 patients, 2 which comprised a targeted retrospective review of patients with known autoimmune pancreatitis. In order to emphasize that IgG4 prostatitis may be underappreciated among pathologists, herein we report detailed findings from a series of patients with histologic evidence of IgG4-RD identified during routine work-up of urologic symptoms.…”

“…While prostatic involvement by IgG4-RD has been estimated at 15% of all IgG4-RD patients, 5 based on the paucity of reports in the genitourinary pathology literature, we suspect IgG4-related prostatitis is an under-appreciated finding for pathologists, which in some instances can have therapeutic and symptomatic implications. 1,2,4,5…”