Granulomatosis with polyangiitis (GPA) is a rare cause of prostatitis. Our case illustrates a case of granulomatous prostatitis secondary to unrecognised GPA requiring multiple surgical interventions. The patient presented with lower urinary tract symptoms. They underwent two endoscopic prostatic resections for recurrent urinary obstruction due to granulomatous prostatitis before a diagnosis of GPA was made. The rarity of this pathology, challenges in making a diagnosis and the systemic nature of this disease are emphasised.