title: Isolated polyarteritis nodosa of the genitourinary tract presenting with severe erectile dysfunction: a case report with long-term follow-up.
abstract: BACKGROUND
  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.
  
  
  OBJECTIVE
  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.
  
  
  METHODS
  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.
authors.affiliation: Department of Urology, University of Pisa, Pisa, Italy;. Electronic address: gianluca.giannarini@hotmail.it.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Giannarini
authors.affiliation: Department of Urology, University of Pisa, Pisa, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Pomara
authors.affiliation: Division of Urology, A.S.S. "Isontina", Gorizia, Italy.
authors.forename: Umberto
authors.initials: U
authors.lastname: Moro
authors.affiliation: Department of Urology, University of Pisa, Pisa, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Mogorovich
authors.affiliation: Department of Urology, University of Pisa, Pisa, Italy.
authors.forename: Filippo Menchini
authors.initials: FM
authors.lastname: Fabris
authors.affiliation: Department of Urology, University of Pisa, Pisa, Italy.
authors.forename: Girolamo
authors.initials: G
authors.lastname: Morelli
authors.affiliation: Institute of Pathology, University of Udine, Udine, Italy.
authors.forename: Cathryn Anne
authors.initials: CA
authors.lastname: Scott
authors.affiliation: Department of Urology, University of Pisa, Pisa, Italy.
authors.forename: Cesare
authors.initials: C
authors.lastname: Selli
mesh_terms: D000328:Adult; D007172:Erectile Dysfunction / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology*; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D058986:Phosphodiesterase 5 Inhibitors; D010726:Phosphodiesterase Inhibitors / Q000627:therapeutic use; D010488:Polyarteritis Nodosa / Q000150:complications* / Q000503:physiopathology*; D012720:Severity of Illness Index; D014566:Urogenital System / Q000503:physiopathology*
chemical_list: D058986:Phosphodiesterase 5 Inhibitors; D010726:Phosphodiesterase Inhibitors