Perianal eczema is confined to the skin around the anus and may rarely involve the perineum. It is unbearably itchy. It is often moist and the skin is infiltrated and thickened and can become chapped. It can develop at any age. Perianal eczema is confined to the perianal skin and may rarely involve the perineum. It is unbearably itchy. The skin is often moist, infiltrated and thickened, and may become chapped. In the acute phase, the rash is mostly dense, corn-sized papules, papules or small blisters with a flushed base. As a result of scratching, the lesions may show obvious punctate exudate and small vesicular surface, the center of the lesion is often heavy, and gradually spread like around, and peripheral and scattered papules, papules, so the boundary is unclear. When combined with infection, the inflammation can be more pronounced and form pustules with pus oozing or yellow-green or dirty brown scabs. It can also be combined with folliculitis, boils, local lymphadenitis, etc. 1, prolapse disease Whether internal hemorrhoids repeatedly prolapse or rectal prolapse or rectal polyps, villiiform papilloma and other diseases, in the process of repeated prolapse, often lead to mucosal congestion, erosion, resulting in inflammatory exudation, these diseases in the process of prolapse secretions often stimulate the perianal skin and stay in the perianal area, over time, the skin formed chronic eczema-like changes. In particular, rectal prolapse severe anal sphincter relaxation, anal closure is not tight, intestinal mucus often overflow anal and eczema. 2, inflammatory diseases long-term alcohol consumption, spicy food, will lead to anal sinusitis or anal canal inflammation, at this time, rectal end anal sinus or anal canal skin congestion or with inflammatory exudate, due to secretions overflowing anal canal will also lead to perianal eczema occur. In addition, the repeated secretion stimulation of anal fistula eventually leads to the occurrence of eczema. 3, surgical sequelae such as excessive excision of anal canal skin resulting in epithelial defects of the anal canal, anal sphincter injury resulting in poor anal closure, anal deformation, or anal incontinence often lead to unconscious overflow of intestinal secretions out of the anus, leading to eczema. 4, intestinal inflammatory diseases chronic intestinal inflammatory diseases such as chronic colitis, proctitis, chronic ulcerative colitis, proctitis, intestinal polyposis, radiation enteritis, intestinal flora imbalance, etc., due to repeated diarrhea, thin stool often stimulates the perianal skin can also cause perianal skin eczema occurs. Perianal eczema is confined to the skin around the anus, and a few can involve the perineum. It is unbearably itchy. The skin is often moist, infiltrated and thickened, and can become chapped. It can develop at any age.