Isolated polyarteritis nodosa of the genitourinary tract presenting with severe erectile dysfunction: a case report with long-term follow-up

INTRODUCTION: Polyarteritis nodosa (PAN) is a rare necrotizing vasculitis affecting small- and medium-sized arteries of multiple organs. Spreading to the genitourinary tract is very common, with invariable involvement of kidneys or testes, but its impact on erectile function remains undetermined. AIM: We describe a case of isolated PAN of the genitourinary tract diagnosed in a young man presenting with severe erectile dysfunction (ED), debate the critical issues of the differential diagnosis, and provide the long-term follow-up outcome. METHODS: The case report profiled a 36-year-old man who presented with progressively worsening erectile function and was incidentally found to suffer from genitourinary PAN. Extensive clinical, laboratory, and instrumental investigations, including brachial artery dilation test, suggested an arteriogenic etiology for ED and excluded a systemic involvement by PAN. Management featured use of a long-term, on-demand phosphodiesterase type 5 (PDE5) inhibitor regimen for ED, and close surveillance with no immunosuppressive therapy for PAN. MAIN OUTCOME MEASURES: Clinical history data, brachial artery dilation test, response to PDE5 inhibitor therapy. RESULTS: After 12 months of PDE5 inhibitor therapy, the patient recovered a normal erectile function, paralleled by restored endothelial function as assessed with brachial artery dilation test. At a 5-year clinical follow-up, he continued to have full erectile ability with only occasional use of PDE5 inhibitor, and no evidence of progressive PAN was documented. CONCLUSIONS: We propose PAN as a novel cause of arteriogenic ED, report the effective therapy with PDE5 inhibitor, and confirm the good long-term prognosis of isolated genitourinary PAN without immunosuppressive treatment.