Uncommon presentation of granulomatosis with polyangiitis: Prostate involvement.

Granulomatosis with polyangiitis (GPA) is an autoimmune granulomatous disease of unknown etiology; frequently associated with anti-proteinase 3 antineutrophil cytoplasmic antibody (PR3-ANCA). Although any organ can be involved, prostatic involvement in GPA is very rare. We present a male patient with GPA, 26 years old, with pulmonary manifestations and prostatic involvement who underwent exhaustive evaluation. The patient's laboratory tests and imaging scans showed evidence of lesions in multiple areas, including the prostate. Histopathological testing confirmed that the lesions were consistent with granulomatosis with polyangiitis. The patient was treated with oral steroids and rituximab and showed significant improvement. He was later maintained on azathioprine without any relapse.