'Prostate Abscess' as the Initial Manifestation of Granulomatosis with Polyangiitis (Wegener's Granulomatosis)

Complex case of granulomatosis with polyangiitis involving the urethra and prostate causing outflow obstruction and ano-urethral fistula

Granulomatosis with polyangiitis (GPA) is an autoimmune small to medium vessel inflammatory vasculitis that can affect multiple organ systems, with predominantly pulmonary, renal and musculoskeletal manifestations. Rarely, there have been cases involving the genitourinary system, particularly causing urethritis and prostatitis. In some incidences, this may mimic prostate abscess or malignancy. We present a case of a 36-year-old man with refractory urinary retention secondary to prostate abscess due to GPA. This case necessitated transurethral resection of the prostate (TURP) and supra-pubic catheterisation, later complicated by a peri-anal abscess and severe urethritis. A potential recto-urethral fistula was noted on magnetic resonance imaging (MRI) and cystourethroscopy, which was managed conservatively with long-term catheter drainage until resolution. The patient ultimately displayed many severe clinical manifestations of a systemic vasculitis and this case report emphasises the importance of considering autoimmune vasculitis conditions as a differential diagnosis when managing inflammatory genitourinary conditions. This case report highlights the importance of obtaining sufficient tissue to make a timely diagnosis in order to initiate immunosuppressant therapy and disease-modifying anti-rheumatic drugs (DMARDs).

[An abscessed granulomatous prostatitis]

INTRODUCTION

Prostatic abscesses are usually diagnosed in the setting of bacterial prostatitis. Rarely, they reveal or complicate granulomatous prostatitis.

CASE REPORT

A 55-year-old man was admitted for acute urinary retention. Urine culture was sterile, with leukocyturia > 10⁶/ml. After failure of antibiotic therapy with cefotaxime, CT scan revealed a necrotic prostatic collection and a nodular non-necrotic tissular lesion in the left upper lung lobe. Trans-rectal drainage of the prostatic lesion and lung biopsies revealed granuloma with multinucleated giant cells (without mycobacteria). The diagnosis of granulomatosis with polyangiitis was confirmed by high level of anti-proteinase 3 antibodies. Treatment with steroids and rituximab resulted in apyrexia, regression of the inflammatory syndrome and clinical manifestations.

CONCLUSION

The diagnosis of granulomatosis with polyangiitis should be considered in the presence of a non-infectious granulomatous prostatitis with systemic involvement.

Prostate involvement in granulomatosis with polyangiitis

To present a case of prostate involvement (PI) in granulomatosis polyangiitis (GPA) and analyse related published reports. We employed the following keywords for retrieving reports indexed by MEDLINE/PubMed and/or Scopus: "granulomatosis with polyangiitis", "Wegener granulomatosis" and "prostate involvement". Additional searches were performed through Google Scholar and HINARI. All cases that fulfilled the American College of Rheumatology criteria for GPA, standards of Chapel Hill Consensus Conference, and did not match with exclusion criteria were analysed and summarised. A 35-year-old man presented with complaints of stuffy nose, difficulty breathing through the nose, swelling and pain in the left half of the nose, low-grade fever, and discomfort. The nasal mucosal biopsy did not reveal any specific changes. During the inpatient treatment, he developed eye redness, tearing, dysuria, and decreased urinary stream. Prostate-specific antigen (PSA) was elevated (2.81 μg/L; normal values ≤ 1.4 μg/L for males below 40 years). Prostate biopsy findings were consistent with diagnosis of GPA, which was confirmed by detecting elevated anti-PR3 antibodies (4.1 IU; normal values < 1.0 IU). We analysed our case in view of the clinical course of 45 published cases of PI in GPA. PI in GPA is a rare clinical manifestation of the vasculitis. Patients with atypical clinical symptoms of GPA are at risk of delayed diagnosis. The awareness of variable clinical presentations of GPA, particularly specific affection of the prostate gland, is crucial for timely diagnosis.