Fistula Treatment
Treatment of an abnormal tunnel between the anal canal and nearby skin, usually requiring specialist assessment
What is fistula treatment?
There are small glands inside the anal canal that drain into it. If one becomes blocked and infected it forms an abscess, and the pus finds its way out through the skin near the anus. When the abscess drains, what is left behind is a tunnel, the fistula, running from inside the canal to the opening on the skin.
That tunnel is lined and it stays open. It fills, discharges, seems to settle, and fills again, sometimes for years. Antibiotics clear the infection in it temporarily and do nothing to the tunnel itself, so it always comes back.
Most fistulas start as an abscess, and most people with one remember the abscess. Some follow Crohn's disease, an injury, radiotherapy or surgery instead. What matters most for treatment is not what caused it but where it runs: a tract that passes through the muscle ring controlling continence is treated very differently from one that stays below it.
What you might notice
- Discharge or wetness near the anus
- Pain or itching around the anus
- A lump near the anus
How it is diagnosed
A doctor examines the skin around the anus for the external opening, feels along the line of the tract, and examines inside to find where it starts. Much of the time that is enough to know what they are dealing with.
Where the tract is high, has branches, or has come back after earlier surgery, they will ask for an MRI of the pelvis. It is the single most useful investigation here, because it shows how the tract relates to the sphincter muscles, and that relationship, more than anything else, decides which operation is safe.
Expect that question to dominate the consultation. The muscle can be divided safely below a certain level and not above it, and every sphincter-sparing technique exists because of what dividing too much of it costs.
Recovery
A fistulotomy leaves an open wound that heals from the base upwards, which takes about four to six weeks and needs daily dressings and showering. It is not painful in the way people expect, but it is slow, and knowing that in advance makes it easier.
A laser closure or a LIFT procedure leaves no open wound and you are usually back to normal within a week. The trade is that they close a lower proportion of fistulas first time, so a second procedure is more likely than after a fistulotomy.
A seton is not really a recovery at all. It is a thread left in place for weeks or months while things settle, and you carry on normally with it in. Your surgeon will tell you what the plan after it is before they put it there.
If it is left untreated
A fistula does not close on its own. That is the single most important thing to know about it, and it is why watchful waiting is not offered.
Left alone, it keeps discharging, which is uncomfortable and hard to live with. It also flares periodically into another abscess, and each flare inflames more tissue and can add branches to the tract. A simple fistula that would have been straightforward to treat can become a complex one over a few years of this.
Very rarely, a fistula present for decades can undergo malignant change. It is uncommon enough that it is not the reason to treat, but it is a reason not to leave one indefinitely.
Questions about fistula treatment
Can a fistula heal without surgery?
No. The tract is lined and stays open, so it fills and discharges however long it is left. Antibiotics settle the infection inside it for a while and do nothing to the tract itself, so it always returns after a course. The only exception is a fistula caused by Crohn's disease, where medical treatment for the Crohn's is part of the plan. Even then the tract itself is usually dealt with surgically.
Will the surgery affect my continence?
It depends entirely on where the tract runs relative to the sphincter, which is why the MRI matters so much. A low tract below the muscle can be laid open with very little risk. A tract crossing the muscle cannot, and the whole family of sphincter-sparing operations, from laser closure and LIFT to an advancement flap or a seton, exists precisely because dividing that muscle would cost control. Ask your surgeon which type yours is and what the specific risk is for that operation.
Why do I need a seton first?
A seton is a soft thread left along the tract to keep it draining. It is used when the tract is high, still infected, or has branches, and it does two things: it stops abscesses forming while you wait, and it lets the inflammation settle so the definitive operation is done on quiet tissue instead of angry tissue. That gives a better result. You carry on normally with it in place, and your surgeon should tell you at the outset what the plan after it is and roughly how long it will stay.
Other proctology treatments
Treatment for swollen veins in the anus or lower rectum, ranging from lifestyle measures to minimally invasive or surgical care
Day CareManagement of a painful tear in the anal lining, with treatment chosen according to severity and duration
Day CareTalk to a care coordinator about fistula treatment
Leave a number and a care coordinator calls you back with what the treatment involves and which hospital it would be at. They book a consult only if you want one