Perianal abscess refers to a formed infective-inflammatory collection within the perianal region. It forms part of the broader group of anorectal abscesses. They are often associated with perianal fistulae and are components of grades 2 and 4 fistulae of the St James’ University Hospital classification 2.
Infection and anal gland drainage obstruction from the perianal fistula may lead to an acute perianal abscess.
Recognised associations include:
- diabetes mellitus
- Crohn disease
- pelvic infection
- anorectal cancer/anal cancer +/- radiation therapy
Treatment and prognosis
While some abscesses may resolve spontaneously via internal drainage into the anal canal, others may require surgical incision and drainage.
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