Sleep-related painful erections

Background A 45-year-old man presented with repeated awakenings at night caused by nocturnal painful erections, in sharp contrast with normal erections at other times, 2 years after surgical removal of a thoracic (Th6-7) ependymoma. Investigations Physical examination, pharmaco-sensitized penile Doppler ultrasound, spinal and brain MRI, nuerophysiological work-up (tibial and perineal somatosensory-evoked potential; hand, foot and perineal sympathetic skin response assessment), polysomnography with recording of nocturnal penile tumescence. Diagnosis Sleep-related painful erections, characterized by penile pain during nocturnal erection, typically during rapid eye movement sleep, in the presence of a residual thoracic spinal cord syndrome. Management Amitriptyline, an antidepressant that suppresses rapid eye movement sleep, was ineffective. Treatments with other antidepressants, clozapine and beta-blockers were suggested, but the patient declined because of potential severe side effects.