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.
- 1. O'Malley RB, Al-Hawary MM, Kaza RK et-al. Rectal imaging: part 2, Perianal fistula evaluation on pelvic MRI-what the radiologist needs to know. AJR Am J Roentgenol. 2012;199 (1): W43-53. doi:10.2214/AJR.11.8361 - Pubmed citation
- 2. Morris J, Spencer JA, Ambrose NS. MR imaging classification of perianal fistulas and its implications for patient management. Radiographics. 20 (3): 623-35. Radiographics (full text) - Pubmed citation
- 3. Li X, Qiang JW, He C et-al. Magnetic resonance imaging study of perianal abscess. Zhonghua Wei Chang Wai Ke Za Zhi. 2013;14 (11): 868-70. Pubmed citation