Primary syphilis of the anorectal region.
D000328:Adult; D001004:Anus Diseases / Q000175:diagnosis*; D003937:Diagnosis, Differential; D005260:Female; D005401:Fissure in Ano / Q000175:diagnosis; D006484:Hemorrhoids / Q000175:diagnosis; D006716:Homosexuality; D006801:Humans; D008297:Male; D008875:Middle Aged; D012002:Rectal Diseases / Q000175:diagnosis*; D012004:Rectal Neoplasms / Q000175:diagnosis; D013587:Syphilis / Q000175:diagnosis*