Definition An abscess is a pocket of pus inside the body. The anus and the area just above it, called the rectum, are common places for an abscess to form. An abscess in either of these areas is known as an anorectal abscess.
What is going on in the body? Infection can cause inflammation. Inflammation creates a wall around the bacteria or other causes of the infection. This wall makes it hard for the immune system to fight the bacteria. The bacteria are protected from attack.
What are the signs and symptoms of the condition? Signs and symptoms of anorectal abscess include:
anal or rectal pain that often gets worse with coughing or straining during a bowel movement
a mass felt by the doctor during rectal examination with a gloved finger
What are the causes and risks of the condition? Most cases are caused by bacterial infection in the lining of the anus or rectum. Chronic constipation may increase the risk of developing an anorectal abscess. Any erosion or small hole in the bowel lining increases the risk of an abscess. Some cases are caused by a condition known as inflammatory bowel disease (IBD). This condition is thought to be due to an autoimmune disorder, in which the person's immune system attacks the bowel for unknown reasons.
What can be done to prevent the condition? Early treatment of erosions of the lining of the bowel can help prevent an anorectal abscess. Treating chronic constipation with stool softeners may also help reduce the risk.
How is the condition diagnosed? Anal pain and a lump that feels like an abscess in the anus are often all a doctor needs to diagnose an anorectal abscess. Special studies of the anus or rectum can determine the size of the abscess. This may include special x-ray tests, such as a CT scan.
A proctoscopy may be done to give the doctor a direct look at the inside of the bowel. A special thin tube with a camera and light on the end of it is inserted into the anus and advanced into the bowel.
What are the long-term effects of the condition? An untreated or incompletely healed anorectal abscess can get worse. It can develop into a fistula or a life-threatening infection. A fistula is an abnormal opening or tract that connects two organs that are not supposed to be connected.
What are the risks to others? An anorectal abscess is not contagious.
What are the treatments for the condition? Treatment of an anorectal abscess usually involves surgery to drain or clean out the pocket of pus. Antibiotics are often used.
What are the side effects of the treatments? Surgery can cause bleeding, worsening infection, or allergic reaction to the anaesthesia. Antibiotics can cause allergic reactions and stomach upset.
What happens after treatment for the condition? After successful treatment and recovery, a person can generally return to normal activities.
How is the condition monitored? Someone with inflammatory bowel disease often needs lifelong monitoring by a doctor. Any new or worsening symptoms should be reported to the doctor.
Author: Adam Brochert, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
