Anal Fistulas and Perianal Abscesses: Symptoms, Causes and Current Treatment Options

Dr. Scott Steele:

Butts & Guts, a Cleveland Clinic podcast exploring your digestive and surgical health from end to end. Hi again, everyone, and welcome to another episode of Butts & Guts. I'm your host, Scott Steele, the president of main campus and colorectal surgeon here at the Cleveland Clinic in beautiful Cleveland, Ohio. And today I'm very pleased to welcome Dr. Ebram Salama, who's a colorectal surgeon at the Digestive Disease Institute at Cleveland Clinic, Florida. Ebram, welcome to Butts & Guts.

Dr. Ebram Salama:

Thank you for having me.

Dr. Scott Steele:

So we're going to talk a little bit about perianal abscesses and fistulas, something that doesn't get a lot of credit, but can sure cause a lot of pain and a lot of problems. But before we do that, give us a little bit about your background to our listeners, where you're from, where the training occurred for you, and how did it come to the point that you're at Cleveland Clinic, Florida?

Dr. Ebram Salama:

Absolutely. I am a Toronto native. I'm currently transplanted down south, working as a colorectal surgeon at the Cleveland Clinic, Florida. I did my medical school and general surgery residency at McGill University in Montreal and then went on to complete a colorectal surgery fellowship at the Cleveland Clinic, Florida in Weston. After fellowship, I worked as a clinical associate under Dr. Wexner and now abroad colorectal surgery practice based here in Western Florida. A big part of what I do involves treating conditions around the anus and rectum, things like hemorrhoids, fissures, abscesses, and fistulas. So I'm really glad that we're talking about this today in a way that's understandable for people who may be dealing with it, but are maybe too embarrassed to ask.

Dr. Scott Steele:

Yeah, absolutely. And so as I said, today we're going to dig into a little bit of perianal abscesses and fistulas. So Dr. Salama, what are perianal fistulas and what is the relationship to perianal abscesses?

Dr. Ebram Salama:

I think the simplest way to picture a fistula is to imagine a little tunnel that shouldn't be there. A tunnel between two areas that shouldn't be communicating. Normally the inside of the anal canal should not be directly connected to the skin around the outside. So in a perianal fistula, there's this abnormal tunnel that runs from the inside of the anus or the rectum to the skin around the anus. That's really what a fistula is.

Now, how does it happen? Inside the anal canal we have these tiny little glands that produce mucus that help lubricate stool as it comes out. And for reasons that we don't fully understand, one of these glands can get inflamed, infected, obstructed, and that builds an infection behind it and the body wants to eliminate that infection, it wants it out. So the body's actually very clever rather than letting that infection spread inside and make you very sick, it tries to push it out towards the skin.

And that usually first shows up as a painful, swollen lump filled with pus underneath the skin near the anus. That's what we call a perianal abscess. That abscess may burst on its own or it may be drained by a healthcare provider if it causes enough discomfort that you seek medical attention. And sometimes everything heals, that's the end of the story, but in a significant number of people who have had perianal abscesses, a tunnel remains that connects the inside of the anal canal to the outside skin. And that persistent tunnel is what we call a perianal fistula. So you can think of it in this way is that an abscess is that initial pocket of infection and the fistula is that leftover tunnel that stays behind in some people after that abscess drains.

Dr. Scott Steele:

So I know we're going to talk a lot about this, but how common are fistulas in the general population?

Dr. Ebram Salama:

If you look at the whole population, anal fistulas, they're not one of the most common conditions, but they're also not that rare either. So large studies estimate prevalence at around 1 in 5,000, maybe to up to 1 in 10,000 at any given time, common enough that we see them quite often in our colorectal practice. Now where it becomes a little bit more relevant is if you've already had an abscess. Someone who's had a perianal abscess that's been drained about 30 to maybe up to 50% of those people will actually go on to develop a fistula. So while the average person on the street may have a relatively low chance of developing a fistula, if you've already had an abscess in that area, your chances are unfortunately much higher.

Dr. Scott Steele:

So I may have some listeners out there like, "Okay, maybe I haven't, maybe I don't." Can you kind of delve a little bit more into the signs and symptoms of both the abscess and the fistula?

Dr. Ebram Salama:

Absolutely. I like to split them into two stages, the abscess stage and the fistula stage. So that abscess stage, people often describe a very painful, tender lump around the anus. They can have some redness and swelling in that area and that pain can be quite severe. It can be worsened when you're sitting on top of it and putting direct pressure or having a bowel movement. Sometimes fevers can accompany this and feeling just general malaise feeling unwell if the infection is more advanced.

And then one of two things happens, either that bursts on its own and you notice pus and blood that drains out with some sudden relief of that pain, or you present yourself to a healthcare provider who makes an incision and drains the pus from that abscess.

Now, if a fistula forms afterwards, the story changes a little bit. In the fistula stage, the main symptoms are this recurrent or repeated episodes of tenderness or discomfort around the anus. It's usually accompanied with a small opening or bump on the skin that drains some fluid. That drainage is often yellowish or white pus like in appearance and can be oftentimes mixed with blood or confused for blood. That discharge generally has a foul odor associated with it and you can get some irritated or itchy skin in that area. Most patients with a fistula describe a cycle where it hurts, it feels swollen and then it drains pus or blood. They feel better. The skin seems to heal and close and then a few weeks later it swells up, hurts again and the cycle repeats this kind of on and off, on again, off again pattern of pain and drainage is very typical for a fistula.

Dr. Scott Steele:

What's the differential diagnosis or other conditions that may be confused with an abscess or fistula?

Dr. Ebram Salama:

Oftentimes an abscess can get confused for a thrombosed external hemorrhoid. That's a situation where one of the small veins around the anus can burst and form a little clot and that clot sits underneath the skin. It creates a very painful lump around the edge of the anus. And so that can have a very kind of similar presentation to an anal abscess. That usually has some association with bowel habits. There's a clear episode of heavy straining, of constipation, of maybe even a severe bout of diarrhea and then that lump pops up. So there is a bit of a temporal relationship between changes in bowel habits and thrombosis external hemorrhoids. Those can bleed eventually, but it's usually just blood. There's no pus mixed in with the blood. It's not particularly foul smelling and it's generally not an issue that continues to persist every few weeks. It's self-limited. It gets better with time. So while hemorrhoids don't usually give you ongoing drainage of pus, they don't create a tunnel from the inside to the outside, they can sometimes be confused with abscesses and fistulas.

Dr. Scott Steele:

I know that there's risk factors that we'll get into for these, but is there anything for just run-of-the-mill average perianal abscess or fistula that our patients can do, our listeners can do to reduce the symptoms of development of either of these?

Dr. Ebram Salama:

I wish I could say yes, but in truth, I'm not sure that there's really a lot that we can reliably do to prevent them. Most of the abscesses and fistulas start from these tiny glands in the anal canal that get inflamed or infected and that process is mostly random, not really strongly tied to diet, exercise or hygiene. That said, some general advice that may be helpful in overall anal health is really avoiding chronic straining, making sure that you're increasing your fiber intake, drinking lots of water and maintaining good bowel habits, keeping that area clean, both gently clean and dried avoiding any harsh soaps or aggressive wiping that can irritate the skin and then managing any underlying comorbidities that can impact your wound healing and immunity. So for example, things like uncontrolled diabetes can really put a damper on wound healing and that affects any parts of the body. In this case, we're talking specifically about fistulas and abscesses. So even though you do everything right you can still get an abscess or fistula, this is not a punishment for something you did or didn't do, unfortunately.

Dr. Scott Steele:

So I often tell patients that we're one long garden hose from our mouse to our bottom and it's that last little bit, if you will, those last five centimeters, there's a lot of confusion along. So can you help our listeners better understand this anatomy? What's a sphincter? What's a dentate line? How does the placement or types of characterization of an abscess or fistula relate to this?

Dr. Ebram Salama:

Absolutely. I'll try my best to keep the jargon to a minimum, but let me start by first defining some of those terms and then putting it all together as it relates to anal fistulas. So I like to think of the anal canal as a tube. It really is a tube and the last segment of our digestive tract. The anal verge is a term is just a fancy term to say the anal opening, that border between the outside skin and the inside of the anal canal. The perianal skin is the skin that is directly around that opening. It's often where we see an external opening of the fistula where the outlet of that tunnel is. A bit inside of this tube about two centimeters in is the dentate line. This is an important landmark. It's a developmental boundary, but it's also more importantly where those little anal glands live and where many abscesses and fistulas start.

So around this tube, this anal canal, there are sphincter muscles that help control your stool, making sure that you're able to keep your continence when it's appropriate. The internal sphincter is an involuntary muscle. Your body controls it automatically. You don't have to think about it. The external sphincter is the one where you can consciously squeeze. When you feel that urge to go, but you're in the middle of a meeting or in the middle of a podcast, that's the muscle that saves the day. So these muscles are very crucial for continents for staying clean and staying in control.

Now, if we come back to that tunnel analogy, a fistula is a tunnel that runs from the anal gland starting at the dentate line and goes out to the skin. And as it travels in that trajectory, it can pass through really just subcutaneously, just the skin that's there and not cross through any muscles. That's called a superficial or a subcutaneous fistula. It can cross through the internal sphincter and exit out skin, that being an intersphincteric fistula, or it can cross through both of those muscles, both the internal and external sphincter. And that's a transsphincteric fistula. It goes across both of those two sphincter muscles. There are some more complex patterns with branches and multiple tunnels, but most of the everyday fistulas that we see follow one of these basic paths and those paths determine how aggressively we can manage them surgically without risking your ability to control your stool.

Dr. Scott Steele:

Yeah, I think that's great. And a very, very good description and as we get into the treatment of it, you'll see why that's important. So let's jump right in there. So is there non-surgical treatments for either abscesses or fistulas?

Dr. Ebram Salama:

Unfortunately, I think the short answer is no. In my opinion, I consider these surgical diseases as do most experts. For abscesses, once you have a pocket of pus, the main treatment is drainage. Whether the body expels out on its own and eventually the skin ruptures and it drains on its own or you seek medical attention and you have it drained, the pus, we need to evacuate that pus one way or another. Antibiotics alone are typically not enough. For fistulas, and this is essentially a surgical disease. Antibiotics can calm things down temporarily, help decrease some of the drainage that's there, but they don't occlude or close that tunnel. Sits baths, which is basically soaking your bottom in warm water for 10 to 15 minutes can help with comfort and hygiene, can help decrease some of the drainage that's happening from those fistulas, but they rarely ever close without any sort of surgical intervention.

Dr. Scott Steele:

Ebram, I thought you brought up a very good point earlier in that about anywhere between 30 and 50% of all abscesses that are drained can develop a fistula. And so I've heard patients say, "Oh, this doctor screwed up. He drained this abscess and now I got this chronic draining fistula and something went wrong." And I think it's important to understand just the anatomy and the physiology of these particular conditions in the anal rectal region, the complexity of it. So you talked a little bit about you drain an abscess and unfortunately becomes a fistula. So what are the current surgical treatment options for fistulas and why is it potentially that you might need multiple operations for a single fistula?

Dr. Ebram Salama:

That's a great question and one that patients ask me all the time, why do we need to do all these procedures for this? And I think it really comes down to understanding the anatomy of the fistula and understanding the trade-off. That trade off is between efficacy of treatment and preservation of sphincter function. So our best treatment for a fistula by far is a fistulotomy. You're looking at 95 to 99% cure rate. What a fistulotomy is, again, going back to our tunnel analogy, it's taking the roof off of that tunnel, just ripping the roof right off and letting everything fill in from the bottom up. If it's a superficial fistula that's easy to do, we open the skin that's over top of it or a small amount of muscle and we let everything fill in from the bottom up and that's a 95 to 99% cure rate for fistulas, on single procedure, excellent efficacy.

Now, occasionally that tunnel as it's tracking through, it goes through both the internal and external sphincters, those are the muscles that are keeping our stools in and keeping us in control. And if I were to un-roof everything over top of that fistula tract and do a fistulotomy, I would effectively have to cut your sphincter muscles. And that can risk leakage or incontinence, especially if you're having episodes of diarrhea or as people age, their sphincters start to weaken. So we really, again, coming back to that trade off of efficacy of the procedure versus sphincter preservation. When we have these transsphincteric fistulas, I often recommend that we go through two stages of an operation.

The first stage is something called a seton placement. Basically a seton is just a fancy way of referring to a little rubber band or a suture that goes from the inside of the anal canal where the internal opening is to the outside opening on the skin. Now moving to a slightly different analogy, if you picture the skin as a dam, the seton's job is to keep that dam open. Every time the skin heals, you basically build a reservoir, a big lake of an infection that builds up behind the skin, builds up enough pressure and then eventually bursts and allows that pus to be evacuated. That's why there's this cyclic nature to a fistula. But what the seton does is it keeps that external opening open and allows the pus to continually drain so you're not building these reservoirs behind the skin.

And once you've really narrowed it down to a small stream with that seton, then you can come in and do a second stage procedure that eliminates the fistula. The two most common ones that we perform are something called a LIFT procedure, which is a Ligation of Intersphincteric Fistula Tract. Basically, we make a small incision around the anal area and dissect between the two sphincter muscles. So we don't actually divide them, but we separate them out and we find the tunnel as it courses through those muscles, tie it off and divide it. That essentially cuts the tunnel in the middle so it can no longer carry the stool or bacteria from the inside to the outside. The success rate of that is about maybe 70, 80% with low rates of incontinence. So we're trading off that 95, 99% success rate of fistulotomy for something that has a little bit of a higher failure rate, but it essentially preserves your sphincters.

The other common operation that I do is an endorectal advancement flap. And this is something where we go from the inside, open up the rectum, close the internal opening of the fistula, and then slide down a flap of healthy rectal lining over to cover that repair and act like a little patch to cover and protect the closure. So these sphincter sparing procedures are less effective than a straightforward fistulotomy, but they protect our continence, which is a trade off that most patients are happy to make when a lot of muscle is involved and essentially why we sometimes need two stages to this operation.

Dr. Scott Steele:

So what does recovery and healing look like after fistula surgery?

Dr. Ebram Salama:

It's a good question. It comes down to what type of fistula surgery was performed. So if it is a two-stage approach, the first stage is placement of the seton, that's a pretty quick recovery. Most people are back to work the next day. There's not a lot of pain associated with that procedure. There's no real cutting that's done in that procedure. I typically leave that seton in place for about 12 weeks, let everything cool off, make sure that we eliminate any lakes of pus that are sitting behind the skin and really let things scar down to a single stream and then proceed with a second stage, definitive closure.

Now the recovery time on a lift or endorectal advancement flap is a little bit longer. I usually recommend that patients take about two weeks off of work because there's quite a bit of discomfort that can be associated with that, especially as you start to have more bowel movements, making their way through that area that you made an incision in. There can be quite a bit of discomfort that needs some downtime. The healing process can take a little bit longer. So in two weeks you're back on your feet, you're doing your normal activities, but I reserve making any judgment on that flap or that lift having succeeded or failed for at least three months after surgery. At that time, the body's continuing to remodel, continuing to settle things down during that time. So it can take up to three months, maybe even longer for that to completely heal.

Dr. Scott Steele:

And are there any exciting treatment options on the horizon for either abscesses or fistulas? I've heard about plugs or stem cell therapy or things like that. Can you talk about that.

Dr. Ebram Salama:

There are a lot of promising avenues that are being studied. Stem cell therapies are one of the most promising where we take stem cells and directly inject them into the fistula tract to encourage healing from within. There is some encouraging data, particularly in Crohn's related fistulas, but it's still evolving and not yet standard of treatment for everyone.

There have been studies done using blood patches where you basically extract the patient's own blood and then inject it into that tract to try to create an inflammatory clotting response that helps the tunnel scar down. Again, an interesting idea, but we need some more robust long-term data.

And there is also some evidence for supportive laser treatments where we place a small little laser probe within the tunnel and then we slowly withdraw it while delivering energy that destroys that nerve lining of the fistula and encourages it to collapse and seal.

Early results are mixed but promising in some series, but at this time though, I wouldn't consider those standard surgical approaches. They're new and up and coming avenues of research.

Dr. Scott Steele

Yeah. And I think again, as a colorectal surgeon myself, I think if you think about it trying to balance how we can get the fistula best healed without a preserving continence and function, that's always the trade off that we're trying to do. So now it's time for our quick hitters, a chance to get to know you a little bit better. So first of all, what is your favorite sport.

Dr. Ebram Salama:

I grew up playing basketball since I was a young kid watching Vince Carter in the early 2000s.

Dr. Scott Steele:

Fantastic.

Dr. Ebram Salama:

It's definitely my choice.

Dr. Scott Steele:

And are you salt or are you sweet?

Dr. Ebram Salama:

Ooh, I like a mix of both, usually in the same dish.

Dr. Scott Steele:

Fantastic. And what is a bucket list trip that you want to go on within the next decade?

Dr. Ebram Salama:

I like to go down to South Africa, do a safari down in South Africa.

Dr. Scott Steele:

And finally, if you could have on superpower to add to your repertoire, what would that superpower be?

Dr. Ebram Salama:

Teleportation.

Dr. Scott Steele:

Ooh, a very good one. So give us a final take home message to our listeners regarding perianal abscesses and fistulas.

Dr. Ebram Salama:

I think my main message is there's not something to be embarrassed about. I don't want people suffering in silence. Really, if you've had a painful lump around the anus, something that's draining pus or blood, something that keeps coming back and really nagging or gnawing on you, extremely important to come seek out a healthcare professional who specializes in colorectal surgery and can help you establish a diagnosis and walk you through the next steps.

Dr. Scott Steele:

Great advice. And so for more information or to make an appointment in the Florida region, please visit clevelandclinicflorida.org/digestive. That's clevelandclinicflorida.org/digestive. And if you're closer to Ohio, please visit clevelandclinic.org/digestive. That's clevelandclinic.org/digestive. Ebram, thanks so much for joining us here on Butts & Guts.

Dr. Ebram Salama:

Thank you.

Dr. Scott Steele:

That wraps things up here at Cleveland Clinic. Until next time, thanks for listening to Butts & Guts.