An anorectal abscess is a collection of pus in the area of the anus and rectum.
Common causes of anorectal abscess include:
Deep rectal abscesses may be caused by intestinal disorders such as Crohn disease or diverticulitis.
The following factors increase the risk for an anorectal abscess:
The condition affects men more than women. The condition may occur in infants and toddlers who are still in diapers and who have a history of anal fissures.
Common symptoms are swelling around the anus and a constant, throbbing pain with swelling. Pain may be severe with bowel movements, coughing and sitting.
Other symptoms may include:
In infants, the abscess often appears as a swollen, red, tender lump at the edge of the anus. The infant may be fussy and irritable from discomfort. There are usually no other symptoms.
A rectal examination may confirm an anorectal abscess. A proctosigmoidoscopy may be done to rule out other diseases.
In some cases, a CT scan, MRI, or ultrasound is needed to help locate the collection of pus.
The problem rarely goes away on its own. Antibiotics alone usually cannot treat an abscess.
Treatment involves surgery to open and drain the abscess.
Drained abscesses are usually left open and no stitches are needed.
The surgeon may prescribe painkillers and antibiotics.
You may need stool softeners. Practice good hygiene. Eat soft or liquid foods until the abscess has healed.
Avoiding constipation will help decrease pain. You may need stool softeners. Drinking fluids and eating foods with lots of fiber can also help.
With prompt treatment, people with this condition usually do well. Infants and toddlers usually recover quickly.
Complications can occur when treatment is delayed.
Complications of anorectal abscess may include:
Call your health care provider if you:
Prevention or prompt treatment of STDs may prevent an anorectal abscess from forming. Use condoms during intercourse, including anal sex, to prevent such infections.
In infants and toddlers, frequent diaper changes and proper cleaning during diaper changes can help prevent both anal fissures and abscesses.
Reviewed By: Debra G. Wechter, MD, FACS, general surgery practice specializing in breast cancer, Virginia Mason Medical Center, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.