[Chronic idiopathic anal pain syndrome]

Abstract

Introduction: The study was undertaken to analyse whether intra-anal ultrasound examination, anorectal physiological evaluation, and histopathological examination of patients suffering from chronic idiopathic anal pain presented any common features and to analyse the results of various treatments.

Material and methods: Eighteen patients who met the criteria for chronic idiopathic anal pain were studied. Treatment included 0.2% glyceryl nitrate ointment, ultrasound guided injection of botulinum toxin in the intrasphincteric space, analgesics, and colostomy.

Results: Anal physiological examinations were normal in all but one patient. Intra-anal ultrasonography demonstrated abnormalities in 12 patients. Defecography showed in one patient a small distal invagination but was otherwise normal. Glyceryl nitrate ointment had an effect in one of four patients, and botulinum toxin in four of nine. Two patients needed a colostomy for definitive pain relief, and in 12 of the 18 patients the final treatment was analgesics.

Discussion: The methods used in this study did not contribute to the understanding of the pathogenesis of chronic anal pain. The treatment is experimental, but injection of botulinum toxin may be tried on the hypothesis that dystonia in the anal sphincter may play a pathogenetic role.