Table of Contents
Anorectal abscesses most commonly result from obstruction of glandular crypts in the anorectal canal. Abscesses are commonly diagnosed by clinical exam with fluctuance, induration, and tenderness around the perianal tissue. Abscesses are managed with incision and drainage. For superficial perianal abscesses bedside lancing can be performed, but for more complex or ischiorectal or postanal abscess, examination under anesthesia in the operating room is preferred. Complete evacuation of the abscess with breakdown of loculated abscess pockets is critical to fully control the infection. Drains may also be left in a deep abscess pocket to prevent the skin prematurely closing before the cavity has healed. Imaging is selectively performed with CT or MRI to identify occult infections or further identify proximal extent of abscess cavity or associated fistula. For recurrent abscesses, associated fistula tracts should also be identified and, if possible, treated intraoperatively. Antibiotics are utilized for patients with cellulitis or those who are immunosuppressed. We present an adult male with recurrent anorectal abscesses with a new anterior abscess collection, which was managed with anal exam under anesthesia with incision and drainage of abscess collection and drain placement.
Anorectal abscesses form due to obstruction of glandular crypts in the anorectal canal.1-3 Anal glands empty into ducts oriented transversely to the internal sphincter and drain into anal crypts at the dentate line.1,3 Obstruction of these ducts and crypts promote infection and abscess formation along perianal and perirectal planes. Common pathogens include: Bacteroides fragilis, Peptostreptococcus, Prevotella, Fusobacterium, Porphyromonas, Clostridium, Staph aureus. Streptococcus, and E. coli.3
Clinically, it is important to describe anorectal abscesses by the anatomic space in which they develop, most commonly perianal and ischiorectal. Additional spaces include intersphincteric, supralevator, submucosal, and postanal spaces.1 The location of the abscess within these spaces will determine whether drainage may be performed internally into the rectal canal, or externally through skin. While the exact percentage ranges from 30–70%, many anorectal abscesses have an associated anal fistula.1 Anorectal abscesses are more common in males with a peak incidence in young-mid adulthood, ages 20–40.1
A male in his 60s with an unremarkable past medical history status post posterior anal abscess drainage with seton placement (x2) one year prior presented with worsening rectal pain. The patient denied bleeding per rectum, changes in bowel movements, or increased pain with defecation.
Physical exam should include a rectal exam to evaluate for fluctuance, induration, tenderness to palpation, and erythema in the perianal area.1 Cellulitis or gross evidence of fistula tracts should also be noted. If the abscess is spontaneously draining, blood or purulent fluid may be appreciated on exam. The depth of the abscess collection can also be evaluated grossly. Superficial abscesses are more likely to drain spontaneously and present without fever in comparison to deeper abscesses. Imaging is not required prior to drainage of an abscess collection. However, ultrasound and MRI may aid in localizing complex abscesses and associated fistulae.1
This patient presented with a right anterior abscess on scrotum with a punctate area of draining pus.
The first line management of an anorectal abscess is incision and drainage.1 Drainage should include interrogation of the wound for any loculated collections that should be subsequently broken down to ensure comprehensive drainage. The skin incision should also be large enough to prevent early closure of the wound and reaccumulation of the abscess. A counter incision may also be necessary to promote drainage and relieve skin tension. Finally, a drain may also be placed to promote drainage.1
Fistula tracts may be identified intraoperatively by injecting H2O2 into the abscess pocket and evaluating for bubbles inside the anorectal canal. In cases of first time abscess drainage, it is unnecessary to look for evidence of fistula. However, if simple fistulas are identified with minimal sphincter involvement, then fistulotomy at the time of the primary incision and drainage is performed to reduce the risk of persistent abscess, recurrence, and need for repeat surgery.1,2 In the case presented, we looked for communication of the abscess with prior fistulotomy sites.
The rate of recurrence of anorectal abscess after incision and drainage is approximately 44% in one year.1 Additional complications from these procedures include fistula formation and fecal incontinence.2
Most patients will not require antibiotics at the time of discharge. However, patients with cellulitis and/or systemic signs of infection or underlying immunosuppression benefit from postprocedural antibiotics.3 Aerobic and anaerobic organisms should be appropriately covered.3 Sitz baths are recommended for all patients postoperatively.
Patients with anorectal abscesses should also be evaluated for additional signs of Crohn’s disease including surgical scars, anorectal deformities, or external fistula openings, and colonoscopy aids in this evaluation to rule out chronic bowel disease.1,3
An adult male with a history of anorectal abscesses presents with anterior perirectal pain and fluid collection with purulent drainage. Patient underwent incision and drainage of abscess collection with Pezzer drain placement to promote complete drainage of abscess collection.
Drain (Pezzer or Malecot).
Nothing to disclose.
The patient referred to in this video article has given their informed consent to be filmed and is aware that information and images will be published online.
- Gaertner WB, Burgess PL, Davids JS, et al. Clinical Practice Guidelines Committee of the American Society of Colon and Rectal Surgeons. The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the management of anorectal abscess, fistula-in-ano, and rectovaginal fistula. Dis Colon Rectum. 2022 Aug 1;65(8):964-985. doi:10.1097/DCR.0000000000002473.
- Malik AI, Nelson RL, Tou S. Incision and drainage of perianal abscess with or without treatment of anal fistula. Cochrane Database Syst Rev. 2010 Jul 7;(7):CD006827. doi:10.1002/14651858.CD006827.
- Sigmon DF, Emmanuel B, Tuma F. Perianal Abscess. [Updated 2022 Jun 21]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK459167/.
Cite this article
Shearer J, Gurland B. Anal examination under anesthesia with abscess drainage and evaluation for fistula. J Med Insight. 2023;2023(370). doi:10.24296/jomi/370.
Table of Contents
- Pre-op Exam
- Pudendal Nerve Block
- Inject More Local Anesthetic
- Clean Cavity
Hi, I am Dr. Brooke Gurland. I'm a colorectal surgeon and I'm gonna show you a little bit about an anal rectal case that I saw. This is a gentleman who is well known to me because I have drained abscesses for him in the past, and I've placed setons. Setons are something that I do for fistula-in-ano to keep the space open. But when he came to my office recently, he had a new swelling in a completely different location. Now it was towards the front, closer to the scrotum. Before it had been towards the back and the posterior location. And so he had a raised area. It was a little fluctuant. It already had been draining. I could see some puss coming out and I recommend that we do a drainage in the OR, so I could get a good look and really open up the cavity. So luckily I was able to get him on, it wasn't an emergency situation, but I had him on electively, but we were able to expedite. And in this case, I did him in the prone position. I wanted to be able to take a good look inside the anus as well as doing the abscess drainage. So my plan for the procedure is really evaluate the extent of the anal area, look and see where, how far the fluctuation is. Once I'm open and I'm draining different material, I wanna make sure to get any loculations out. I wanna open and clean the cavity out. In general, I do not usually look for fistulas when I'm draining an abscess, but because of his previous history, I also wanted to just take a look and see if they communicated. And he had an area that was a little bit indurated on the side. Also, my plan was to check and see how far things extended.
He has known fistulas here and here, but this is where his new abscess is, and it's all the way kind of extending into the groin. And so that's what this looks like. We're gonna shave a little bit and then position him, and then clean out this abscess cavity. And you know, really, he has a history of abscesses and fistula. This is the last thing I did. These are both setons, right? They keep the space open and prevent. This is now in a new brand new location.
So we're gonna do a pudendal block. Okay. All right, so sometimes it can be hard to get someone anesthetized who has an abscess. So I'm gonna start with a block and we start it away from where that is. Now go ahead, you can give on the other side. Feel where you feel that tuberosity, you'll go medial to it, aspirate. And then after that, we'll give a bit on each side. We'll give a little bit on that skin. Yep. We've got some great anesthesia. He's under a heavy sedation, but isn't moving and feels great. And then I would also just comment on the fact that these are some chronic... These setons have been in for some time, and they allow him to go to work without any infections. And this is... It's a recent infection in the last couple months.
Okay. So let's see. So let's give a little local just around this site. What we're gonna do, 'cause I could see in the office that there was some drainage, and we're gonna end up opening that up, that cavity. Yep. So give a little bit around here. Yep. Yeah. Okay. A little bit on the side over here. Okay. Okay, great. Okay, nice.
So why don't you - this, see where this is already bulging out? Why don't we take on a 15 blade and we'll just kind of open this up a little bit. And then I'll take a Kelly, just around this area right here that's enlarged. So just, yep, take a 15 blade. 15. And we're gonna drain this abscess. And actually, look, I just popped right through it 'cause it was ready, it was a cavity underneath. I'm just gonna have you take the knife, or it could be a Bovie at this point, but just open it up because we want it large enough that it can really drain. There you go. That's good enough. Go ahead, open it. Right here or laterally? All right, I'm opening it for us. There you go, 'cause look at this cavity. This potential cavity is - I'm putting my finger in. Okay. You can see that this is a cavity. So just take the Bovie and just right on my finger here. So this is... Yep, just open up the skin a little bit if I... Okay, great. Okay, let's see in this direction. I'm gonna break up some loculation. I know I'm cheating a little bit. And then I'm gonna have us go a little bit in this direction because I don't want it to close too soon. Yeah, we'll get rid of the edges. So this is a big cavity, like you can get a sense of this. Okay. So let's do this. I'm gonna have you take a little bit of the skin 'cause I do not want this. This'll close very soon. And just come around, just around, just not so much. I don't need you to take all that skin. I just don't want it to close. Yeah, right, like just take a little. No, yeah. No, yeah, not that much. I don't need that amount of skin. Yeah, there you go. Perfect. Right, because... And then take a little of that and just so that it doesn't - yeah, heal in. Very nice. Okay, so let's take some irrigation. And that is an abscess that has been drained. And what I did with the little skin edge is I just didn't want the skin to close too soon, 'cause if the skin closes, and I have this deep cavity, now it's still a little bit deep, and maybe I do need to leave a drain or something in. But... I broke up loculations. So let's take a look now on the inside. So can I have those lighted anoscopes? Those will really help us. And we'll look to see if this communicates with anything on the inside. Yes, there's lighted anoscopes. There's a light cord. I'd really like those.
The lighted anoscopes? All right, we'll take a little bit of lube and we'll use the anoscopes that you have. Yep, the lighted anoscopes, please. Okay. So we'll take a look and we'll look to see what it looks like on the inside. I'll take the anoscope that you have. No, I like the half... Yeah, but the largest one. The larger one. Yeah. Okay, thanks. Okay, let's look and see. And then I'm gonna want an angiocath with hydrogen peroxide just to see, so... In general, when I'm draining an abscess, I just drain the abscess and then move on. But in this case where he has had chronic fistula, I'm gonna look to see if it communicates with any of the other fistula, any of the other sites. But this is really in a completely different location. And I don't see any openings. This looks really good here. Okay.
Okay, and then I'm gonna... I think what I will do for him is, here's my consideration. Let's take a little bit of this so that this doesn't heal too soon. Let's take a little bit more skin. And then just this little edge, not too much. Just the little edge so that we'll have this corner, this cavity, yeah. And I'm a little bit worried. See how it drops all the way down here. I don't know that he can manage this. I certainly don't wanna pack it, but maybe I'll leave a drain in there. Can I have a curette, please? I'm gonna clean this cavity out. Go ahead. You're gonna take the curette and clean that out. So what I'm thinking about is, I know that he has to go back to work, and that's really a very big deal for him not to miss any work. So I'm trying to think what will give him the best, what'll be easiest for him. And he also, I'm not sure really that he has any help to help with doing any kind of dressing changes. Kind of trying to think to myself, "What can we do?" And, maybe what I will do is I will put just the edge of packing in and ask to see if he can just put something, otherwise I leave a drain. So this will stay open for a little bit. I think what I'm gonna do is I'm gonna put a little bit of packing in, tell him to change it, not pack deep. All right? And then have him come back to the clinic and see me. And then I can take a look at it. But this is really quite a deep cavity. The other option would be to leave a drain in there. I am gonna put a little bit of a drain. I'm gonna put a Pezzer drain in here and suture it into place. And then I'll bring him back to the office and we'll take it out. I just don't want it to close too soon. I wanna give this time. But this is really quite a large potential cavity. You can kind of feel there's some fluctuance here too. That's a little bit, that bothers me a little bit. Let's see if we go in this direction. But I don't wanna make so you almost get... Like you know that here... This is a... So maybe what I'll do is just put the drain in and then wait to see. And we did it before. Okay, so let's just... This is nice 'cause we can take a look on the inside. Very nice. Okay. Great. So, there we go. All right, can I just have some dilute hydrogen peroxide? I'm just gonna take a look and see. Yeah, I probably don't even need the angiocath. Can you hold this for me? I'm just looking to see if it... And if none of those things, then it's just I'm doing a little bit of cleaning, but he's not gonna like it. It's a little bit burn. Hold on, hold on, hold on. I'm looking to see. Okay, hold on. Right, I'm not seeing any. All right. Okay, we'll take some more irrigation. And then can I get a Pezzer drain, please? Yeah. The Pezzer drain, like a 20. It's called a Pezzer drain. Okay, I got it. Okay, thanks. Like a 20. Yep. All right, I'm gonna put a drain in here, and then we can call it a day. These all look good, though. They're nice and clean.
All right, let's look at the edges, make sure that we're happy. Take a Bovie, just curate these edges a little bit. Make sure nothing's bleeding. Not curette, Bovie. Okay. And here. It was right there. Right here in the base. Can I have a Raytec instead? Would that be possible? Okay. Anything else bleeding? It looks pretty good to me. Okay. And then what we'll do is we'll put the drain so that it goes in that direction. And then she's just gonna need a stitch for the drain. I just don't love how full this feels, but I'm not sure what else I can do about that right this minute. Actually, maybe what we should do on him... Let's see if this communicates this way at all. Maybe what we should do is make a counter incision here. I'll just take a... I'm just gonna do something like this. Okay. Just because I'd rather... We know he's got extensive fistulas, and I'd rather leave another outlet for an opening. Okay. But I'm not seeing any more pus or anything. So I made a counter. Okay. And this connects with this. So... Sometimes people can get loculations. I just don't want one area to close.
Okay. So I think this is as good as it gets. Yep, great. All right. So, Pezzer drain. And then I'll take this out in the office. Okay, so we'll take some sort of drain stitch where you just put this to the most... I guess it's dependent. You're just gonna sew that onto the skin right there. It can be anything, I don't care if it's chromic. Whatever you have. Actually, I'd prefer like a 3-0 or a 2-0. Something a little heavier. Yeah, anything's okay. It's not gonna last forever. So I made this counter incision, partly because I know him, and I did one abscess drainage, and then we had to go repeat - he had to come back the next day. So I didn't wanna do the same thing here. And I figured that this'll just heal, if there's no problem. I just wanted to give adequacy for drainage. Okay, I'm gonna have you use this. This isn't our typical stitch. Go ahead. You're gonna just use that. You're gonna put it through the edge. Yeah, that's fine. Okay. Your idea is not... Go ahead, take that. Can she have a DeBakey or something? Or Adsons maybe. Okay. Okay, and then you can wrap this around. That's all you have to do. You're just gonna tie this into place. This is your drain stitch, so wrap that around. Yep. And then tie that into place. Wrap this one around? Yep. Wrap it around and then tie it down. Okay. There you go. Can you just squirt her hands? Because chromic could be a little bit... Yeah. Okay. Scissors, please. Thanks. Okay. So I don't need this to stay in forever. I'm keeping this in over the weekend. Let things drain a little bit. It will not be that fun for him to have this hanging out. And if it comes out on its own, I'm okay with that. And that's one of the reasons that I used chromic. I don't mind if it comes out.
Okay. I've done what I can do here. I drained an abscess. I'm leaving a drain in that we can take out in the office. I made a counter incision because I didn't know if this was an area of fluctuance and I know that this'll heal on its own. And my biggest problem is usually the skin heals, and then the abscess reaccumulates. And then I have to see in context with the fact that he already has two additional setons and posterior fistulas, exactly what's happening with him. So I might image him later. Alright, all good. Thanks.
In this specific case, because of the size of the cavity, I was concerned that the skin would heal too soon, and I'd be left with a cavity underneath. And I'm not a big fan of packing where someone has to keep putting a little gauze inside of a cavity just 'cause it's super hard for patients to do. And I prefer to use a drain. And in this case I use a Pezzer drain and I choose a specific size based on the opening. I placed that in and I sutured it to the skin. That will be removed in the office, and this will prevent the skin from closing too soon. If the skin closes too soon, then I will be left with another cavity and an area ripe for infection. So on this gentleman, I did not see an additional fistula. I saw the abscess, I cleaned it out. And very possibly in the future I'll do an an MRI or some sort of imaging to get more visualization to see if any of these - if these connect. Thank you very much.