HealthInfo Canterbury
Anorectal abscess
Whēwhē ki te tou
An abscess is an infected collection of pus in your body. When it occurs near your anus or rectum, it's called an anorectal abscess.
There are different types of anorectal abscesses depending on their location around your anus and anal muscles.
Anorectal abscesses are more common in men than women, and mostly happen between the ages of 20 and 50. These infections can be serious – especially if you have diabetes or reduced immunity.
Causes of anorectal abscesses
Anorectal abscesses sometimes start in a gland located between the two rings of muscles in your anus called sphincters. It happens when bacteria get into the gland, causing an infection that grows into an abscess. It could also start with an anal fissure, from a sexually transmitted infection (STI) or blocked glands in your anus.
Symptoms of anorectal abscesses
Symptoms differ, but you may:
- notice a painful lump in your anus or bottom
- feel a severe throbbing pain that gets worse when you sit down, move, cough or go to the toilet
- see some pus or blood-stained fluid come from the lump if it starts to leak
- have a fever, sweating or shaking episodes
- lose your appetite or feel tired and unwell.
Diagnosing anorectal abscesses
Your general practice team will ask you about your bowel habits and any stomach pain you've been feeling. They will examine the area around your anus to look for swelling or signs of infection. They may need to put a gloved finger into your bottom to feel the abscess.
If your general practice team finds an anorectal abscess, they will refer you to the General Surgical Team at the hospital for treatment.
Treating anorectal abscesses
On arrival, you'll have a blood test. If you're very unwell, you may be given antibiotics. An MRI scan could be needed to find out how deep the abscess is in your bottom.
If the abscess needs to be surgically drained, you'll be given a general anaesthetic. The abscess will be cut open, drained out and the wound packed and dressed.
After surgery, you may need to have your wound repacked daily so it can heal. This is usually managed by a district nurse. You should see your general practice team two weeks after surgery and again at 6 weeks to make sure you're healing well.
Self-care after anorectal abscess draining
After your surgery, you'll feel some discomfort. It's important to have good pain relief, such as paracetamol and anti-inflammatories (NSAIDS) that you can take regularly.
Other things to consider as you recover include:
- drinking plenty of fluids to reduce the chance of becoming constipated
- eating a well-balanced diet high in fibre
- avoiding pushing too hard when going to the toilet.
Anal fistula
You could develop a fistula (a tunnel between your skin and anal canal). If this happens, you'll be referred back to the General Surgical Outpatient Clinic for follow up and further treatment as needed. This happens in approximately 30% of patients with an anorectal abscess.
Recurrent abscess
In some people, an abscess can recur requiring further treatment.
Risks of general surgery
Having surgery involves some risks but these are usually outweighed by the benefits. Your surgeon will discuss the likely risks with you.
It's important that you take adequate pain relief while your anal area is healing.
HealthInfo recommends the following pages
- Colorectal Surgical Society of Australia and New Zealand – Condition information
Information about common conditions including anal abscess, anal fistula, anal fissure and diverticular disease.
- Patient.info – abscess
Information about abscesses, prevention, and treatment options.
Written by HealthInfo clinical advisers. Last reviewed July 2022.
SourcesReview key: HIARA-13012
