Anal Abscess
What is an anal abscess?
An anal abscess is a painful condition caused by a collection of pus near the anus or rectum.
What causes an anal abscess?
It is often the result of a bacterial infection that develops in the glands inside the anus. These glands become blocked, leading to accumulation of bacteria and pus.
What are the symptoms of an anal abscess?
Pain: Often severe and localised around the anus.
Swelling: A tender lump near the anus.
Fever: Sometimes accompanied by chills if the infection is more severe.
Discharge: Pus or fluid draining from the abscess.
How is an abscess treated?
Incision and drainage: The primary treatment involves making an incision to allow the pus to drain from the abscess. This procedure is typically performed under general anaesthesia. The wound is usually left open to heal on its own.
Antibiotics: Depending on the severity of the infection, antibiotics may be prescribed to clear the infection.
In some cases, especially if an abscess is recurrent or associated with a fistula, further surgical procedures might be needed to prevent recurrence and address the underlying cause.
Prompt medical attention is crucial for anal abscesses to prevent spread of infection and to ensure proper treatment. If left untreated, abscesses can worsen and lead to more serious complications.
What is an anal fistula?
An anal fistula is an abnormal tunnel-like tract that connects the anal canal or the rectum to the skin near the anus.
What are the symptoms of a fistula?
Pain: Persistent discomfort, often around the anus.
Discharge: Pus or foul-smelling drainage from an opening near the anus.
Swelling or redness: Around the affected area.
What causes a fistula?
Anal abscess: Often, an anal fistula develops as a complication of an untreated or inadequately treated anal abscess. When an abscess doesn’t heal properly and the infection persists, it can create a tunnel-like passage, forming a fistula.
How is a fistula treated?
The initial goal of surgery is to treat the infection. This involves examination of the fistula under a general anaesthetic and insertion of a seton (thread or rubber-band like material) into the fistula. Further investigations such as a MRI scan or colonoscopy may be required.
Once the infection is under control, there are various procedures to treat the fistula depending on the characteristics of the fistula.
Fistulotomy – In this procedure, the surgeon cuts open the entire length of the fistula to lay it open. This allows for drainage and promotes healing. It is effective for straightforward fistulas but might not be suitable for complex or high-risk fistulas.
LIFT (Ligation of Intersphincteric Fistula Tract) – This technique involves identifying and closing off the internal opening of the fistula. It is a sphincter saving technique and is preferred for certain types of fistulas to reduce the risk of continence.
Mucosal advancement flap – A flap of healthy tissue is created and used to cover the internal opening of the fistula. This technique aims to preserve sphincter function and promote healing.
Fistula plug – This is a medical device made of an absorbable bioprosthetic material (collagen or porcine small intestinal mucosa) which is inserted into the fistula to seal the internal opening. The plug aims to encourage the growth of tissue around it.
Multiple attempts at surgery are often required before a fistula is fixed. The success of each technique varies greatly with a fistulotomy having a success rate above 90%. The remaining techniques have a success rate of 50% and lower.