Glucose-6-Phosphate Dehydrogenase Deficiency: An Etiology for Idiopathic Priapism?

INTRODUCTION: Efforts to identify the health risk associations for priapism may reveal pathophysiologic mechanisms for the disorder and suggest a scientifically rational approach for correcting it. AIM: We describe a clinical presentation of idiopathic recurrent priapism in a patient with glucose-6-phosphate dehydrogenase (G6PD) deficiency and consider a possible nitric oxide (NO)-dependent mechanistic basis from which the medical condition causes priapism. METHODS: The case report profiled a 35-year-old African-American man with G6PD deficiency who presented with a rapid progression of recurrent priapism episodes. He was outwardly healthy and did not have sickle cell disease or trait by hematologic screening. His management featured use of a long-term, continuous phosphodiesterase type 5 (PDE5) inhibitor therapeutic regimen. MAIN OUTCOME MEASURES: Clinical history data and response to PDE5 inhibitor therapy. RESULTS: After a 3-month duration of PDE5 inhibitor therapy, priapism recurrences were sufficiently resolved and the patient discontinued therapy. At 18-month clinical follow-up, he experienced only minor priapism recurrences and retention of full erectile ability. CONCLUSIONS: G6PD deficiency offers an explanation for idiopathic priapism. The medical condition generates a pathophysiologic milieu consistent with aberrant NO signaling and heightened oxidative stress in the penis.