Perianal Abscesses

In this article

What is a perianal abscess? What causes an abscess? What complications can happen? How is an abscess treated? Recovery from abscess draining surgery What if the abscess comes back?

What is a perianal abscess?

A perianal abscess is a cavity filled with pus found near the back passage (‘anus’). It is a common condition. This can cause pain, tenderness, redness and/or a lump in the region of the anus sometimes with a fever.

What causes an abscess?

A perianal abscess is believed to be caused by infection getting in to one of the glands that produces mucus to lubricate the anus. However, there are some underlying diseases which can frequently cause perianal abscesses such as inflammatory bowel disease like Crohn's disease.

What complications can happen?

When an abscess has discharged itself or has been lanced (“drained”), the skin will usually heal over. Sometimes, however, a small hole is left on the outside. This usually means that a tunnel (a “fistula”) has developed between the anal gland and the outside opening. Only a minority of people who have had an abscess will go on to develop a fistula.

How is an abscess treated?

If the infection is caught very early on, antibiotics may work. However, the majority of abscesses will require to be drained. This usually requires a general anaesthetic (put to sleep) and a short stay in hospital. It will usually take a few weeks for the abscess cavity (hole) that has been drained to  fill up with scar tissue. Sometimes (but often not) the cavity will require “packing”. 

If there is also a possibility of a fistula, a clinical test for it can be done at the time of the pus drainage and if possible a draining seton can be applied. However, a fistula nearly always requires well planned surgery to cure it. The majority of fistulae are relatively easy to treat but should preferably be performed by a specialist in gastroenterological surgery.

Recovery from abscess draining surgery

The healing of an abscess cavity will usually take a few weeks. It may be necessary for a gauze pad to be worn in the underwear for a week or two after the operation to prevent the drainage from soiling the clothes.

Bowel movements will not affect the healing. Discomfort after  perianal abscess surgery is moderate for the first week and can be controlled with simple pain killers. The amount of time off work is usually about a week.

Bathing or showering two to three times a day helps keep the area clean and comfortable. Laxatives are recommended to minimise the discomfort associated with passing a motion.

What if the abscess comes back?

Perianal abscesses can come back. In this case it may be necessary to exclude an underlying condition such as inflammatory bowel disease or a perianal sinus or a fistula. This will warrant further investigations.