Beware of anal fissures: pemphigus vulgaris of the anal canal.

A case of anal pemphigus vulgaris in a 49-year-old female suffering from pemphigus vulgaris of the oral cavity is reported. The oral manifestations were in remission until she presented with episodes of anal pain and bleeding on defecation, initially mimicking anal fissures. Inspection revealed prominent painful erosions in the anal canal with external hemorrhoids and strands of sloughing skin and maceration in the anal verge. Histology and direct immunofluorescence test were consistent with pemphigus vulgaris. The disease was refractory to treatment and complete remission was only achieved with the combination of rituximab and corticosteroids. Anal involvement seems to be an uncommon or underreported manifestation of pemphigus vulgaris. Gastroenterologists should be aware of this entity, especially in areas with a high incidence of the disease, for appropriate diagnosis and management.