[Digestive localizations of sexually transmitted diseases in male homosexuals]. / Localisations digestives des maladies sexuellement transmissibles chez l'homosexuel mâle.

The common practice of sexual relations with many different and anonymous partners and the great variety of responsible micro-organisms account for the high incidence, growing complexity and uneasy prevention of sexually transmitted diseases of the digestive tract in male homosexuals. Syphilis, gonorrhoea, papillomas, chancroid, donovanosis, herpes virus or Chlamydia infections are known to be transmitted by anal coitus; amebiasis, giardiasis and shigellosis by oro-anal contact (faecal contamination). Still under discussion, however, are the predominant mode of transmission of Campylobacter jejuni, the true frequency in homosexuals of intestinal anguilluliasis, oxyuriasis and salmonellosis and the anorectal pathogenicity of Neisseria meningitidis, intestinal spirochetes, Mycoplasma homini, Ureaplasma urealyticum and Campylobacter-like organisms. Diagnosis is difficult since these infections are polymicrobial as a rule and often clinically asymptomatic or atypical and may be further modified by features of the acquired immunodeficiency syndrome, traumatic lesions or anorectal tumours. Microbiological examination is an essential prerequisite to rational treatment.

[Vascularization of the anal canal]. / Vascularisation sanguine du canal anal.

The arterial blood supply of the anal canal derives from the superior, middle and inferior rectal arteries, whose branches reach the anal submucosa. Three main arterial trunks in the right anterior, right posterior and left lateral positions can be isolated below the pectinate line. They come, for the most important part, from the superior rectal artery. On the course of the anal submucosal venous plexus are fusiform, saccular or serpiginous dilatations confined to the lower half of the anal canal. This plexus is mainly tributary of the superior rectal vein to the portal system and secondly, of the middle and inferior rectal veins and the lateral sacral veins to the inferior vena cava. Arterio-venous direct communications have been demonstrated by serial section and by radiography of cadaveric specimens and by selective inferior mesenteric arteriography in patients. The erectile property of the anal submucosa as suggested by large vascular spaces, arterio-venous shunts and glomic systems may function in the erectile mechanism.