What is a perianal abscess? A perianal abscess is an abscess formed by infection of the soft tissues around the anus, characterized by the eventual formation of an anal fistula. The clinical manifestations of perianal abscesses vary depending on where they occur, but they generally have the following symptoms: hard nodular masses: Initially, hard nodular masses rise around the anus and gradually increase in size, some of which can break down on their own over time. Pus flow: Pus flow is the main symptom of anal fistula, usually more from a newly created tube and less from a paralyzed one. Fistulas sometimes appear to be temporarily free of pus, when there is localized swelling and pain and a rise in body temperature. Pain: Swelling, soreness, and burning discomfort may occur, and the symptoms worsen when walking or defecating. Itching: When the skin around the anus is stimulated by pus and secretions, the patient will feel itching of the skin. Poor defecation: Some patients may have difficulty in defecating and have a feeling of incomplete defecation. Systemic symptoms: Some patients may have fever, peripheral discomfort, lethargy, and lack of appetite. How is perianal abscess treated? A few perianal abscesses can be dissipated with antibiotics, hot water sitz baths and local physiotherapy, but most require surgery, which varies depending on the location of the abscess. 1.Perianal abscess incision and drainage can be performed under local anesthesia, and a radial incision with the anus is made at the most obvious fluctuation to ensure unobstructed drainage. 2.Sciatic anal canal interstitial abscess should be performed under lumbar or sacral anesthesia, puncture with a thick needle at the most obvious place of pressure pain, extract the pus, make an arc-shaped incision parallel to the anal verge at that place to avoid damaging the sphincter, probe the pus cavity so that the drainage is unobstructed, and then place a tube or oil gauze to drain. 3.Pelvic rectal interstitial abscess incision and drainage should be performed under lumbar or sacral anesthesia, and the incision site varies depending on the source of the abscess. If the abscess protrudes into the intestinal cavity and fluctuations can be palpated by fingers in the rectum, rectal wall incision and drainage should be performed in the corresponding area under anoscopy; if the abscess originates from trans-sphincteric anal fistula infection, the drainage method is similar to that of sciatic anal canal gap abscess. The majority of perianal abscesses form anal fistulas after incision and drainage. In recent years, the use of abscess incision and drainage plus one-stage suturing has been reported, which can avoid the formation of anal fistula.