Somatosensory phenotyping in women with persistent genital arousal disorder: a case-control study.

Introduction: Persistent genital arousal disorder (PGAD) is a rare and distressing condition characterized by persistent, unwanted genital arousal in the absence of sexual desire or stimulation. Persistent genital arousal disorder is increasingly recognized as a disorder of abnormal genital sensory processing, but objective neurophysiological data remain limited. Methods: We conducted an exploratory case-control study to characterize somatosensory function in women with PGAD. Thirty women with PGAD and 30 age-matched healthy controls were recruited at Leiden University Medical Center. Participants underwent quantitative sensory testing (QST) at hand and external genital sites, conditioned pain modulation, and corneal confocal microscopy. Results: Hand QST values were within normal range in both groups. In the genital region, PGAD participants showed altered thermal pain processing, with cold and heat hyperalgesia compared with controls. Mechanical pain thresholds did not differ between groups; however, PGAD participants reported higher pain intensity ratings to mechanical stimuli and showed significantly greater temporal summation of pain in genital regions. Genital dynamic mechanical allodynia occurred more frequently in PGAD participants but did not differ significantly at the group level. Conditioned pain modulation magnitude did not differ between groups and showed substantial interindividual variability. Corneal confocal microscopy abnormalities were observed in a proportion of participants in both groups without significant between-group differences. Discussion: These findings show that QST is feasible in women with PGAD and indicate that PGAD is associated with altered somatosensory processing demonstrating genital thermal hypersensitivity and central pain sensitization in a subset of patients.