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The morbidity of constipation in patients with anorectal malformations
Journal of Pediatric Surgery (2010) 45, 1228–1233
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The morbidity of constipation in patients with anorectal malformations Marc A. Levitt ⁎, Adrien Kant, Alberto Peña Colorectal Center for Children, Cincinnati Children's Hospital, Division of Pediatric Surgery, University of Cincinnati, Cincinnati, Ohio 45229, USA Received 16 February 2010; accepted 23 February 2010
Key words: Anorectal malformation; Imperforate anus; Fecal incontinence; Morbidity; Constipation; Megasigmoid
Abstract Background: Constipation in anorectal malformations (ARM) is extremely common, particularly in the lower types. Failure to adequately treat it can lead to significant morbidity. Methods: From our series of over 2000 patients with ARM, we reviewed 398 with good prognosis for bowel control and a tendency toward constipation; rectoperineal fistula (63), rectovestibular fistula (114), rectobulbar urethral fistula (104), imperforate anus with no fistula (46), rectal atresia or stenosis (9), and cloaca with a common channel below 3 cm (62). Those lost to follow-up, not yet toilet-trained (b3 years old), or with poor prognostic features were excluded. We compared morbidities in patients we operated on and managed primarily (group A, n = 268) to those managed at other institutions who suffered from constipation or incontinence and were referred to us for treatment (group B, n = 130). Those we managed primarily were subjected to an aggressive senna-based laxative program, started after their primary repair or after colostomy closure. Results: Morbidities associated with constipation were higher in the referral group and included fecal impaction (7.8% vs 38.5%), overflow pseudoincontinence (4.9% vs 33.8%), and megacolon (14.6% vs 54.6%). A loop or transverse colostomy (4.9% vs 9.2%), stoma or anorectal stricture, or a stenotic fistula (2.2% vs 28.5%) were contributing factors. Adequate laxative treatment with, in certain cases, resection of a megarectosigmoid (2.6% vs 23.1%) enabled many pseudoincontinent children to achieve bowel control (reported previously). Unneeded colorectal biopsies (1.9% vs 16.2%), Hirschsprung's-type pullthroughs (0% vs 3.1%), and, in retrospect, unneeded antegrade continent enema procedures (0% vs 3.1%) were higher in Group B. Overall, 19.8% of Group A and 66.2% of Group B experienced constipation-related morbidities. Conclusion: The morbidity of constipation in ARM includes fecal impaction, megacolon, incontinence, and performance of unneeded surgeries. Inadequate treatment, the type of the original colostomy, and postoperative anal or stomal stricture as well as stenotic fistulae were key contributing factors. Children with ARM and good prognosis for bowel control are at the greatest risk for severe constipation and its consequences. With recognition and aggressive, proactive treatment, we have found that these morbidities can be reduced. © 2010 Elsevier Inc. All rights reserved.
⁎ Corresponding author. Tel.: +1 513 636 3240; fax: +1 513 636 3248. E-mail address: [email protected] (M.A. Levitt). 0022-3468/$ – see front matter © 2010 Elsevier Inc. All rights reserved. doi:10.1016/j.jpedsurg.2010.02.096
The morbidity of constipation in patients with anorectal malformations Constipation in anorectal malformations (ARM) is extremely common, particularly in the lower types with good prognosis for bowel control [1-5], which include imperforate anus with no fistula, rectal atresia or stenosis, rectoperineal fistula, males with rectourethral fistula at the bulbar level, and females with rectovestibular fistula or cloaca with a common channel of less than 3 cm. Constipation in its most serious forms can produce overflow pseudoincontinence, frequently related to a dilated rectosigmoid [6-10]. Failure to recognize or adequately treat this associated hypomotility in ARM patients can lead to significant morbidity [4,6-10], which we believe is largely preventable. Minor childhood constipation is often dismissed as dietrelated or behavioral. Diet does have some impact on colonic motility, and treating constipation with stool softeners may be sufficient in mild cases, but their therapeutic value is negligible in the most serious forms of constipation. The rectosigmoid normally stores the stool, and active peristaltic waves occur every 24 to 48 hours indicating that it is time to empty. A normal individual, with an intact continence mechanism, feels this sensation, contracts their sphincter, and then decides when to relax the voluntary sphincter mechanism to allow evacuation. The ability to have a voluntary bowel movement depends on the combined integrity of the anal canal, sphincters, and motility [11]. Patients with anorectal malformations lack a normal anal canal, have variably deficient sphincters, and have an accompanying motility disorder, usually hypomotility [8,11]. Management for this depends on treatment of constipation with laxatives to provoke peristalsis and to overcome the dysmotility. A child with a correctly repaired good-prognosis anorectal defect, normal lumbosacral spine, good sphincters, and an intact rectosigmoid should be fecally continent [1], so that if such a patient is soiling, we can expect that they are not being adequately treated for constipation. Hirschsprung's disease is sometimes suspected when a child with ARM has severe constipation, and some clinicians perform biopsies [12,13]. In fact, Hirschsprung's disease is no more common in patients with ARM than in the general population [8]. Some surgeons have even done Hirschsprung's type pullthroughs in these patients, but loss of the rectum (a common part of certain pullthroughs for ARM done mostly before 1985 [14]) leads to loose stool and requires treatments that slow down the colon. Unfortunately, most of these patients become fecally incontinent, because, in addition to the lack of a true anal canal and deficient sphincters, they now no longer have a rectal reservoir and, thus, cannot retain loose stool or rely on proprioception for help with a voluntary bowel movement [15]. Therefore, such a resection when constipation is misinterpreted for Hirschsprung's can lead to fecal incontinence. For patients with true fecal incontinence, a bowel management program is an artificial way to keep them clean with daily enemas [11,15]. For most ARM patients (75%), with the potential for continence, medical manage-
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Table 1 Indicators of prognosis for bowel control in anorectal malformation patients Good prognostic features
Poor prognostic features
• Normal sacrum / spine • Abnormal sacrum • No presacral mass • Myelomeningocele • Good buttock crease • Some types of ARM • Good anal dimple ◦ Rectoprostatic urethral fistula • Some types of ARM ◦ Rectobladder neck fistula ◦ Rectoperineal fistula ◦ Cloacal exstrophy cloaca ◦ Rectobulbar urethral fistula ◦ N3 cm common channel ◦ Rectovestibular fistula ◦ Complex defects ◦ Cloaca b 3 cm common channel ◦ Rectal atresia or stenosis ◦ Imperforate anus without fistula
ment consists of avoidance and treatment of constipation, as well as effective potty training strategies [11]. Therefore, only a small minority require washouts and, thus, would need a Malone or cecostomy. In this review, we sought to objectively assess the consequences of constipation in ARM who have good potential for bowel control (Table 1). We hypothesized that there is a lower incidence of morbidity when constipation is managed early and effectively.
1. Methods From our series of over 2000 patients with ARM, we reviewed the charts of 398 patients with good potential for fecal continence (Table 2) and a tendency toward constipation, including those with rectoperineal fistula (63), rectovestibular urethral fistula (114), rectobulbar urethral fistula (104), cloaca with common channel below 3 cm (62), imperforate anus with no fistula (46), and rectal atresia or stenosis (9). These patients historically have a good prognosis for bowel control. [1] Those lost to follow up, not yet toilet-trained (or b3 years old), or with poor prognostic features (Table 1) were excluded. We compared morbidities in patients we operated on and managed primarily with an aggressive constipation avoidance protocol (group A, n = 268) to those operated on, treated primarily or managed postoperatively at other institutions who suffered from constipation or incontinence and were referred to us for treatment, operation or reoperation (group B, n = 130) [25]. In group A, constipation was treated with the following protocol: a senna-based laxative was begun after primary repair or after colostomy closure. Stool softeners were avoided because they make the stool too soft, and they do not help to provoke a bowel movement. We found stimulant laxatives in this patient group more effective as they are designed to increase the motility of the colon. Although often
1230 Table 2
M.A. Levitt et al. Constipation-related morbidities in groups A and B
Constipation-related morbidities in Groups A and B Group A n = 268 Group B n = 130 Fecal impaction 21 Pseudoincontinence 13 Megacolon 39 Sigmoid resection 7 Hirschsprung's biopsy 5 Hirschsprung's 0 pullthrough Cecostomy/ 0 appendicostomy
7.8% 4.9% 14.6% 2.6% 1.9% 0.0%
50 44 71 30 21 4
38.5% 33.8% 54.6% 23.1% 16.2% 3.1%
0.0%
4
3.1%
therapy and resection of a massive megarectosigmoid (2.6% vs 23.1%) enabled many pseudoincontinent children to achieve bowel control (a finding that we have reported previously) [8,11]. Unneeded colorectal biopsies were performed in 21 patients (1.9% vs 16.2%). Hirschsprung'stype pullthroughs were performed in four patients. Four had an antegrade continent enema procedure which, in retrospect, after successful laxative treatment, they did not need. Overall, 19.8% of group A and 66.2% of group B patients experienced morbidities related to their constipation.
3. Discussion discussed as a concern by parents and physicians, we are unable to find any long term problems related to senna usage. We sometimes add pectin to the regimen which gives the stool a little bulk and makes the laxative more efficient. The goal was 1 to 2 well-formed stools per day. To ensure regular emptying, the parents are instructed to give the laxative each day and then observe the child for the next 24 hours. If the patient does not have a bowel movement in the 24 hours, or does not empty completely, it means the laxative dose was not enough, and it must be increased. An enema is given in order to remove the stool produced during the previous 24 hours, and the laxative dose is increased. The routine of giving an enema, if needed, and increasing the laxative are then continued. The child should stool daily. We monitor them with an occasional abdominal radiograph to confirm colonic emptying. We defined overflow pseudoincontinence as soiling in a constipated patient who, once treated adequately with laxatives, has voluntary bowel movements and stops soiling. Such patients have benign malformations, a normal sacrum and spine, and good sphincters, yet they soil. Fecal impaction was defined as episodes requiring hospitalization for disimpaction. Those patients with poor prognosis defects, an abnormal sacrum and spine, a flat bottom, and poor sphincters were considered to be in the true incontinence group and were not part of this review. Group B patients were referred for a variety of reasons. Those with good prognosis for bowel control but with constipation-related morbidities were analyzed. The protocol for their treatment and evaluation has been reported on previously [8,11,15].
We recognize that this review is inherently flawed because there is no way to know the denominator of patients with ARM who have constipation, and we do not know precisely what treatments were employed before referral to our center. Clearly, the problem of constipation is very common particularly in the benign types, and we found that, in many patients, it was not recognized or treated aggressively [1]. It was our intention therefore to show that when constipation is proactively managed from early in life, and a good bowel movement pattern (1-2 well-formed stools per day and objective, radiologic confirmation of emptying) is established, children with ARM with good prognosis should potty train successfully [1]. We hypothesized that when constipation is not adequately treated, and patients present after many years, they can have overflow pseudoincontinence and other constipation related morbidities. We do not understand why many of these patients suffer from different degrees of dilation of the distal colon, usually a megarectosigmoid (Figs. 1 and 2A), but surmise that a hypomotility disorder exists that interferes with complete emptying of the rectosigmoid, which leads to progressive dilation. This process sometimes may start in utero as the newborn colon can be found already dilated (Fig. 1) [7,8,16,17], but usually, this is a process that develops over time.
2. Results Morbidities associated with constipation included episodes of fecal impaction (group A = 7.8% vs group B = 38.5%), usually with overflow pseudoincontinence (4.9% vs 33.8%), and varying degrees of megacolon (14.6% vs 54.6%) (Table 2). A loop or transverse colostomy (4.9% vs 9.2%), and/or stomal or anorectal stricture or stenotic fistula (2.2% vs 28.5%) were key contributing factors. Laxative
Fig. 1
Megarectosigmoid in a newborn.
The morbidity of constipation in patients with anorectal malformations
Fig. 2
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A, Megasigmoid. B, Colorectal anastomosis after sigmoid resection. J Pediatr Surg. 1993; 28: 1-5.
Constipation in anorectal malformations is a selfperpetuating disease. We know that dilation of a hollow viscus leads to poor peristalsis [18], which can explain how constipation leads to fecal retention and results in increasingly greater degrees of megasigmoid, which then exacerbates the constipation in a vicious cycle. We surmised that with an early and aggressive laxative regimen, we could potentially interrupt this cycle. Colonic dilation can also occur when the distal limb of a colostomy is very long or not cleaned out, or from stool
spillage, when it is not completely diverted from the proximal stoma [19]. This dilation leads to more constipation. We also observed varying degrees of megacolon in patients with postoperative stomal or anal strictures, in patients who did not perform or continue anal dilations, and in children with stenotic perineal or vestibular fistulas in whom the anoplasty was delayed. Soiling of the underwear in an older child is an ominous sign of bad constipation and may represent overflow pseudoincontinence. This phenomenon was more common
Fig. 3 A, Contrast enema showing megarectosigmoid. B, Absent (previously resected) rectosigmoid with straight colonic segment from the splenic flexure to the perineum (note the haustrations in the pelvis). Printed with kind permission from Curr Probl Surg. 2002; 39: 661-732.
1232 in the patients whose degree of constipation was unrecognized and is a common source of referral to our Center [15]. These patients behave as if they are fecally incontinent, but when the constipation is treated adequately, the great majority regain bowel control [11]. Of course, this clinical presentation of soiling may also occur in a patient with a poor prognosis ARM, and an associated spinal or sacral anomaly. For such a patient who has true incontinence, bowel management with a daily enema is needed [15]. Most of the time, the dose of laxative that the patient needs in order to empty the rectosigmoid completely, as demonstrated radiologically, can be achieved. At that dose, the pseudoincontinent patient should stop soiling, because by successfully emptying the distal colon each day, the child will remain clean until the laxative provokes the next voluntary bowel movement(s). Occasionally, in the process of increasing the amount of laxative, a patient may be unable to tolerate (as evidenced by cramping, nausea, or emesis) the amount required to empty the colon daily. Such a patient may be a candidate for surgical intervention, a sigmoid resection. The megarectosigmoid is resected, and the descending colon is anastomosed to the residual rectum (Fig. 2). We attribute the smaller incidence of megarectosigmoid (Fig. 3A) found in our patients to our early and vigilant treatment of constipation. Our incidence was not zero, however, which is potentially explained by a congenital dilation, or our own inadequate treatment and/or follow-up care. After a sigmoid resection, the amount of laxative required to treat these children can be significantly reduced or even eliminated [6,7]. The more localized the dilation of the rectosigmoid, the better the results of its resection [7]. These patients are not cured, however, and must be followed up closely, because the remaining distal colon can redilate. Before performing this operation, it is mandatory to confirm that the patient is definitely suffering from overflow pseudoincontinence rather than true fecal incontinence with constipation—that is, whether the child remains clean and has effective voluntary bowel movements provoked by adequate laxative treatment. Failure to make this distinction may lead to an operation in which a fecally incontinent constipated child is changed to one without an adequate reservoir and a tendency to have loose stool, which is much more difficult to manage. Unfortunately, this is what happened to many ARM patients who were initially treated by abdominoperineal and/ or endorectal pullthrough operations [14] used commonly before the introduction of the PSARP. Loss of the rectal reservoir (Fig. 3B) led many of these children to lose their potential for continence, making them dependent on enemas [15]. Greater understanding and appreciation of this fact, along with widespread practice of the posterior sagittal approach, has considerably reduced the frequency of this outcome [20]. It still occurs, however, when similar operations are undertaken in attempts to treat severe constipation. Faced with severe or recurrent constipation in a child with an ARM, some physicians suspect Hirsch-
M.A. Levitt et al. sprung's disease and, as noted, obtain rectal biopsies to rule out this possibility. Some even proceeded with rectosigmoid resections. Unfortunately, this leads to loose stools and fecal incontinence [15]. We believe that, in the absence of characteristic contrast studies or episodes of enterocolitis, the likelihood of Hirschsprung's disease in conjunction with a known anorectal malformation is very low and does not warrant biopsy or rectosigmoid resection [8]. Other clinicians attempted to treat “unmanageable” constipation with antegrade enemas through a catheterizable stoma or button device [21,22]. We have found, though, that once their constipation is effectively treated medically with laxatives, patients can become continent and turn out not to need washouts at all. We reserve antegrade enemas procedures for incontinent patients who require a daily washout [11]. Despite the limitations of this review, mainly owing to the fact that the referred patients are a non-representative group, as they are referred because they are having problems, the trends we have documented are clear. We regard these morbidities as mostly preventable, despite the fact that some were present in our own patients. In our group, morbidities were mainly related to the patient having rectosigmoid dilation starting at birth, or from inadequate follow up. With an aggressive constipation avoidance and treatment protocol, we were able to see a lower rate of morbidity. The morbidity of constipation in ARM is an impressive list, including impaction, megacolon, pseudoincontinence, and performance of unindicated or unnecessary surgeries. In addition to inadequate treatment, other preventable causes include type and location of the original colostomy (transverse and loop colostomies) postoperative stricture and delayed treatment of a narrow perineal or vestibular fistula. Noncompliance or poor follow-up also contributes to increased morbidity from constipation. It is imperative to understand that children with anorectal malformations with the best prognosis for bowel control are at the greatest risk for severe constipation and its consequences. With appropriate recognition and aggressive, proactive treatment, these morbidities can be significantly reduced.
References [1] Levitt MA, Peña A. Imperforate anus and cloacal malformations. In Pediaric Surgery, 5th ed, Holcomb GW & Murphy JP (editors) Elsevier Saunders, Philadelphia. pp. 337-59 [In Press]. [2] Heinen F. The surgical treatment of low anal defects and vestibular fistulas. Semin Pediatr Surg 1997;64:204-16. [3] Rintala R. Fecal incontinence in anorectal malformations, neuropathy, and miscellaneous conditions. Semin Pediatr Surg 2002;11: 75-82. [4] Rintala R, Lindahl H, Rasanen M. Do children with repaired low anorectal malformations have normal bowel function? J Pediatr Surg 1997;32:823-6. [5] Pakarinen M, Koivusalo A, Lindahl H, et al. Prospective controlled long-term follow-up for functional outcome after anoplasty in boys with perineal fistula. J Pediatr Gastroenterol Nutr 2007;44:436-9.
The morbidity of constipation in patients with anorectal malformations [6] Keshtgar A, Ward H, Richards C, et al. Outcome of excision of megarectum in children with anorectal malformation. J Pediatr Surg 2007;42:227-33. [7] Peña A, El-Behery M. Megasigmoid: a Source of pseudo-incontinence in children with repaired anorectal malformations. J Pediatr Surg 1993; 28:1-5. [8] Peña A, Levitt MA. Colonic inertia disorders in pediatrics. Curr Probl Surg 2002;39:661-732. [9] Smith E. The identification and management of anorectal anomalies— the factors ensuring continence. Prog Pediatr Surg 1976;9:7-40. [10] Kim H, Gow K, Penner J, et al. Presentation of low anorectal malformations beyond the neonatal period. Pediatrics 2000;105:e68. [11] Levitt MA, Peña A. Update on pediatric fecal incontinence. Eur J Pediatr Surg 2009;19:1-9. [12] Kiesewetter W, Sukarochana K, Sieber W. The frequency of aganglionosis associated with imperforate anus. Surg 1965;58: 655-71. [13] Stevenson J, Herron P. Hirschsprung's disease: a rare cause of constipation in patients following surgical correction of imperforate anus: report of 2 cases. Am Surg 1967;33:555-8. [14] Kiesewetter W. Imperforate anus: the role and results of the sacroabdomino-perineal operation. Ann Surg 1966;164:655-61. [15] Bischoff A, Levitt M, Bauer C, et al. Treatment of fecal incontinence with a comprehensive bowel management program. J Pediatr Surg 2009;6:1278-84. [16] Holschneider A, Koebke J, Meier-Ruge W, et al. Pathophysiology of chronic constipation on anorectal malformations. Long-term results and preliminary anatomical investigations. Eur J Pediatr Surg 2001;11: 305-10. [17] Stephens F. Rectal ectasia: primary and secondary associated with anorectal anomalies. Birth Defects Org Artic Ser 1988;24:99-104. [18] Nixon H. An experimental study of propulsion in isolated small intestine and applications to surgery in the newborn. Ann R Coll Surg Engl 1960;27:105-24. [19] Peña A, Migotta-Krieger M, Levitt MA. Colostomy in anorectal malformations: a procedure with serious but preventable complications. J Pediatr Surg 2006;41:748-56. [20] Holschneider A, Pfrommer W, Gerresheim B. Results in the treatment of anorectal malformations with special regard to the histology of the rectal pouch. Eur J Pediatr Surg 1994;4:303-9. [21] Malone P, Ransley P, Kiely E. Preliminary report: the antegrade continence enema. Lancet 1990;336:1217-8. [22] Rakic S, Baeten C. Laparoscopic appendicostomy with cecoplication for antegrade colonic enema procedure. Surg Laparosc Endosc Percutan Tech 2004;14:165-6.
Discussion Gail Besner, MD (Columbus, OH): Could you comment on the three patients that were referred to you from elsewhere who had pull-through procedures that were not indicated? Marc Levitt, MD (Cincinnati, OH) (response): These patients had severe constipation as their only symptom.
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These are patients that underwent biopsies. Those biopsies were done too low so there may have been “absence of ganglion cells”, but there was no comment on whether the nerves are hypertrophic or not. Those patients ultimately underwent rectosigmoid resections and pullthroughs, and sadly, those patients became incontinent because of the hypermotility induced by that resection. Obviously, they didn't have the greatest anal canal or sphincter by nature of their anorectal malformation and could not handle the hypermotility. This is something that needs to be avoided. These patients did not have Hirschprung's disease. Daniel Von Allmen Md (Cincinnati, Ohio): Do you think there was a selection bias since the patients who were referred may have been more complex? Marc Levitt, MD (response): I believe that this is certainly a factor. We do not intend in any way to compare the two groups. These are obviously complex patients. We have no idea what the denominator is. My only point of utilizing the two groups was to show that with an aggressive management scheme from colostomy closure on, you can dramatically reduce the morbidity. Even in the group managed in our institution, we did not come close to zero, there was still a significant amount of morbidity, but you can dramatically reduce it if you're very aware of it and treat it aggressively. Don Nakayama, MD (Macon, Ga): What kind of laxatives do you use on your patients? Marc Levitt, MD (response): We use senna-based laxatives. Most of the things on the market are actually stool softeners, and we regularly stop the stool softeners and change them over to something with a stimulant component, something with senna, I think in these patients, the problem is not hard stool but rather motility of the colon. So giving them a stool softener just makes the stool soft, it doesn't really help it come out, and they have a colon full of stool that doesn't empty, and in fact, may empty in more of a leakage kind of way and they're worse. Many patients will tell you that they're much worse on a stool softener such as MiraLAX; once you put them on something stimulating, it actually empties the distal part of the colon and they do a lot better. It's important to remember that distinction. We routinely are stopping stool softeners and switching patients to laxatives.
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The morbidity of constipation in patients with anorectal malformations Marc A. Levitt ⁎, Adrien Kant, Alberto Peña Colorectal Center for Children, Cincinnati Children's Hospital, Division of Pediatric Surgery, University of Cincinnati, Cincinnati, Ohio 45229, USA Received 16 February 2010; accepted 23 February 2010
Key words: Anorectal malformation; Imperforate anus; Fecal incontinence; Morbidity; Constipation; Megasigmoid
Abstract Background: Constipation in anorectal malformations (ARM) is extremely common, particularly in the lower types. Failure to adequately treat it can lead to significant morbidity. Methods: From our series of over 2000 patients with ARM, we reviewed 398 with good prognosis for bowel control and a tendency toward constipation; rectoperineal fistula (63), rectovestibular fistula (114), rectobulbar urethral fistula (104), imperforate anus with no fistula (46), rectal atresia or stenosis (9), and cloaca with a common channel below 3 cm (62). Those lost to follow-up, not yet toilet-trained (b3 years old), or with poor prognostic features were excluded. We compared morbidities in patients we operated on and managed primarily (group A, n = 268) to those managed at other institutions who suffered from constipation or incontinence and were referred to us for treatment (group B, n = 130). Those we managed primarily were subjected to an aggressive senna-based laxative program, started after their primary repair or after colostomy closure. Results: Morbidities associated with constipation were higher in the referral group and included fecal impaction (7.8% vs 38.5%), overflow pseudoincontinence (4.9% vs 33.8%), and megacolon (14.6% vs 54.6%). A loop or transverse colostomy (4.9% vs 9.2%), stoma or anorectal stricture, or a stenotic fistula (2.2% vs 28.5%) were contributing factors. Adequate laxative treatment with, in certain cases, resection of a megarectosigmoid (2.6% vs 23.1%) enabled many pseudoincontinent children to achieve bowel control (reported previously). Unneeded colorectal biopsies (1.9% vs 16.2%), Hirschsprung's-type pullthroughs (0% vs 3.1%), and, in retrospect, unneeded antegrade continent enema procedures (0% vs 3.1%) were higher in Group B. Overall, 19.8% of Group A and 66.2% of Group B experienced constipation-related morbidities. Conclusion: The morbidity of constipation in ARM includes fecal impaction, megacolon, incontinence, and performance of unneeded surgeries. Inadequate treatment, the type of the original colostomy, and postoperative anal or stomal stricture as well as stenotic fistulae were key contributing factors. Children with ARM and good prognosis for bowel control are at the greatest risk for severe constipation and its consequences. With recognition and aggressive, proactive treatment, we have found that these morbidities can be reduced. © 2010 Elsevier Inc. All rights reserved.
⁎ Corresponding author. Tel.: +1 513 636 3240; fax: +1 513 636 3248. E-mail address: [email protected] (M.A. Levitt). 0022-3468/$ – see front matter © 2010 Elsevier Inc. All rights reserved. doi:10.1016/j.jpedsurg.2010.02.096
The morbidity of constipation in patients with anorectal malformations Constipation in anorectal malformations (ARM) is extremely common, particularly in the lower types with good prognosis for bowel control [1-5], which include imperforate anus with no fistula, rectal atresia or stenosis, rectoperineal fistula, males with rectourethral fistula at the bulbar level, and females with rectovestibular fistula or cloaca with a common channel of less than 3 cm. Constipation in its most serious forms can produce overflow pseudoincontinence, frequently related to a dilated rectosigmoid [6-10]. Failure to recognize or adequately treat this associated hypomotility in ARM patients can lead to significant morbidity [4,6-10], which we believe is largely preventable. Minor childhood constipation is often dismissed as dietrelated or behavioral. Diet does have some impact on colonic motility, and treating constipation with stool softeners may be sufficient in mild cases, but their therapeutic value is negligible in the most serious forms of constipation. The rectosigmoid normally stores the stool, and active peristaltic waves occur every 24 to 48 hours indicating that it is time to empty. A normal individual, with an intact continence mechanism, feels this sensation, contracts their sphincter, and then decides when to relax the voluntary sphincter mechanism to allow evacuation. The ability to have a voluntary bowel movement depends on the combined integrity of the anal canal, sphincters, and motility [11]. Patients with anorectal malformations lack a normal anal canal, have variably deficient sphincters, and have an accompanying motility disorder, usually hypomotility [8,11]. Management for this depends on treatment of constipation with laxatives to provoke peristalsis and to overcome the dysmotility. A child with a correctly repaired good-prognosis anorectal defect, normal lumbosacral spine, good sphincters, and an intact rectosigmoid should be fecally continent [1], so that if such a patient is soiling, we can expect that they are not being adequately treated for constipation. Hirschsprung's disease is sometimes suspected when a child with ARM has severe constipation, and some clinicians perform biopsies [12,13]. In fact, Hirschsprung's disease is no more common in patients with ARM than in the general population [8]. Some surgeons have even done Hirschsprung's type pullthroughs in these patients, but loss of the rectum (a common part of certain pullthroughs for ARM done mostly before 1985 [14]) leads to loose stool and requires treatments that slow down the colon. Unfortunately, most of these patients become fecally incontinent, because, in addition to the lack of a true anal canal and deficient sphincters, they now no longer have a rectal reservoir and, thus, cannot retain loose stool or rely on proprioception for help with a voluntary bowel movement [15]. Therefore, such a resection when constipation is misinterpreted for Hirschsprung's can lead to fecal incontinence. For patients with true fecal incontinence, a bowel management program is an artificial way to keep them clean with daily enemas [11,15]. For most ARM patients (75%), with the potential for continence, medical manage-
1229
Table 1 Indicators of prognosis for bowel control in anorectal malformation patients Good prognostic features
Poor prognostic features
• Normal sacrum / spine • Abnormal sacrum • No presacral mass • Myelomeningocele • Good buttock crease • Some types of ARM • Good anal dimple ◦ Rectoprostatic urethral fistula • Some types of ARM ◦ Rectobladder neck fistula ◦ Rectoperineal fistula ◦ Cloacal exstrophy cloaca ◦ Rectobulbar urethral fistula ◦ N3 cm common channel ◦ Rectovestibular fistula ◦ Complex defects ◦ Cloaca b 3 cm common channel ◦ Rectal atresia or stenosis ◦ Imperforate anus without fistula
ment consists of avoidance and treatment of constipation, as well as effective potty training strategies [11]. Therefore, only a small minority require washouts and, thus, would need a Malone or cecostomy. In this review, we sought to objectively assess the consequences of constipation in ARM who have good potential for bowel control (Table 1). We hypothesized that there is a lower incidence of morbidity when constipation is managed early and effectively.
1. Methods From our series of over 2000 patients with ARM, we reviewed the charts of 398 patients with good potential for fecal continence (Table 2) and a tendency toward constipation, including those with rectoperineal fistula (63), rectovestibular urethral fistula (114), rectobulbar urethral fistula (104), cloaca with common channel below 3 cm (62), imperforate anus with no fistula (46), and rectal atresia or stenosis (9). These patients historically have a good prognosis for bowel control. [1] Those lost to follow up, not yet toilet-trained (or b3 years old), or with poor prognostic features (Table 1) were excluded. We compared morbidities in patients we operated on and managed primarily with an aggressive constipation avoidance protocol (group A, n = 268) to those operated on, treated primarily or managed postoperatively at other institutions who suffered from constipation or incontinence and were referred to us for treatment, operation or reoperation (group B, n = 130) [25]. In group A, constipation was treated with the following protocol: a senna-based laxative was begun after primary repair or after colostomy closure. Stool softeners were avoided because they make the stool too soft, and they do not help to provoke a bowel movement. We found stimulant laxatives in this patient group more effective as they are designed to increase the motility of the colon. Although often
1230 Table 2
M.A. Levitt et al. Constipation-related morbidities in groups A and B
Constipation-related morbidities in Groups A and B Group A n = 268 Group B n = 130 Fecal impaction 21 Pseudoincontinence 13 Megacolon 39 Sigmoid resection 7 Hirschsprung's biopsy 5 Hirschsprung's 0 pullthrough Cecostomy/ 0 appendicostomy
7.8% 4.9% 14.6% 2.6% 1.9% 0.0%
50 44 71 30 21 4
38.5% 33.8% 54.6% 23.1% 16.2% 3.1%
0.0%
4
3.1%
therapy and resection of a massive megarectosigmoid (2.6% vs 23.1%) enabled many pseudoincontinent children to achieve bowel control (a finding that we have reported previously) [8,11]. Unneeded colorectal biopsies were performed in 21 patients (1.9% vs 16.2%). Hirschsprung'stype pullthroughs were performed in four patients. Four had an antegrade continent enema procedure which, in retrospect, after successful laxative treatment, they did not need. Overall, 19.8% of group A and 66.2% of group B patients experienced morbidities related to their constipation.
3. Discussion discussed as a concern by parents and physicians, we are unable to find any long term problems related to senna usage. We sometimes add pectin to the regimen which gives the stool a little bulk and makes the laxative more efficient. The goal was 1 to 2 well-formed stools per day. To ensure regular emptying, the parents are instructed to give the laxative each day and then observe the child for the next 24 hours. If the patient does not have a bowel movement in the 24 hours, or does not empty completely, it means the laxative dose was not enough, and it must be increased. An enema is given in order to remove the stool produced during the previous 24 hours, and the laxative dose is increased. The routine of giving an enema, if needed, and increasing the laxative are then continued. The child should stool daily. We monitor them with an occasional abdominal radiograph to confirm colonic emptying. We defined overflow pseudoincontinence as soiling in a constipated patient who, once treated adequately with laxatives, has voluntary bowel movements and stops soiling. Such patients have benign malformations, a normal sacrum and spine, and good sphincters, yet they soil. Fecal impaction was defined as episodes requiring hospitalization for disimpaction. Those patients with poor prognosis defects, an abnormal sacrum and spine, a flat bottom, and poor sphincters were considered to be in the true incontinence group and were not part of this review. Group B patients were referred for a variety of reasons. Those with good prognosis for bowel control but with constipation-related morbidities were analyzed. The protocol for their treatment and evaluation has been reported on previously [8,11,15].
We recognize that this review is inherently flawed because there is no way to know the denominator of patients with ARM who have constipation, and we do not know precisely what treatments were employed before referral to our center. Clearly, the problem of constipation is very common particularly in the benign types, and we found that, in many patients, it was not recognized or treated aggressively [1]. It was our intention therefore to show that when constipation is proactively managed from early in life, and a good bowel movement pattern (1-2 well-formed stools per day and objective, radiologic confirmation of emptying) is established, children with ARM with good prognosis should potty train successfully [1]. We hypothesized that when constipation is not adequately treated, and patients present after many years, they can have overflow pseudoincontinence and other constipation related morbidities. We do not understand why many of these patients suffer from different degrees of dilation of the distal colon, usually a megarectosigmoid (Figs. 1 and 2A), but surmise that a hypomotility disorder exists that interferes with complete emptying of the rectosigmoid, which leads to progressive dilation. This process sometimes may start in utero as the newborn colon can be found already dilated (Fig. 1) [7,8,16,17], but usually, this is a process that develops over time.
2. Results Morbidities associated with constipation included episodes of fecal impaction (group A = 7.8% vs group B = 38.5%), usually with overflow pseudoincontinence (4.9% vs 33.8%), and varying degrees of megacolon (14.6% vs 54.6%) (Table 2). A loop or transverse colostomy (4.9% vs 9.2%), and/or stomal or anorectal stricture or stenotic fistula (2.2% vs 28.5%) were key contributing factors. Laxative
Fig. 1
Megarectosigmoid in a newborn.
The morbidity of constipation in patients with anorectal malformations
Fig. 2
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A, Megasigmoid. B, Colorectal anastomosis after sigmoid resection. J Pediatr Surg. 1993; 28: 1-5.
Constipation in anorectal malformations is a selfperpetuating disease. We know that dilation of a hollow viscus leads to poor peristalsis [18], which can explain how constipation leads to fecal retention and results in increasingly greater degrees of megasigmoid, which then exacerbates the constipation in a vicious cycle. We surmised that with an early and aggressive laxative regimen, we could potentially interrupt this cycle. Colonic dilation can also occur when the distal limb of a colostomy is very long or not cleaned out, or from stool
spillage, when it is not completely diverted from the proximal stoma [19]. This dilation leads to more constipation. We also observed varying degrees of megacolon in patients with postoperative stomal or anal strictures, in patients who did not perform or continue anal dilations, and in children with stenotic perineal or vestibular fistulas in whom the anoplasty was delayed. Soiling of the underwear in an older child is an ominous sign of bad constipation and may represent overflow pseudoincontinence. This phenomenon was more common
Fig. 3 A, Contrast enema showing megarectosigmoid. B, Absent (previously resected) rectosigmoid with straight colonic segment from the splenic flexure to the perineum (note the haustrations in the pelvis). Printed with kind permission from Curr Probl Surg. 2002; 39: 661-732.
1232 in the patients whose degree of constipation was unrecognized and is a common source of referral to our Center [15]. These patients behave as if they are fecally incontinent, but when the constipation is treated adequately, the great majority regain bowel control [11]. Of course, this clinical presentation of soiling may also occur in a patient with a poor prognosis ARM, and an associated spinal or sacral anomaly. For such a patient who has true incontinence, bowel management with a daily enema is needed [15]. Most of the time, the dose of laxative that the patient needs in order to empty the rectosigmoid completely, as demonstrated radiologically, can be achieved. At that dose, the pseudoincontinent patient should stop soiling, because by successfully emptying the distal colon each day, the child will remain clean until the laxative provokes the next voluntary bowel movement(s). Occasionally, in the process of increasing the amount of laxative, a patient may be unable to tolerate (as evidenced by cramping, nausea, or emesis) the amount required to empty the colon daily. Such a patient may be a candidate for surgical intervention, a sigmoid resection. The megarectosigmoid is resected, and the descending colon is anastomosed to the residual rectum (Fig. 2). We attribute the smaller incidence of megarectosigmoid (Fig. 3A) found in our patients to our early and vigilant treatment of constipation. Our incidence was not zero, however, which is potentially explained by a congenital dilation, or our own inadequate treatment and/or follow-up care. After a sigmoid resection, the amount of laxative required to treat these children can be significantly reduced or even eliminated [6,7]. The more localized the dilation of the rectosigmoid, the better the results of its resection [7]. These patients are not cured, however, and must be followed up closely, because the remaining distal colon can redilate. Before performing this operation, it is mandatory to confirm that the patient is definitely suffering from overflow pseudoincontinence rather than true fecal incontinence with constipation—that is, whether the child remains clean and has effective voluntary bowel movements provoked by adequate laxative treatment. Failure to make this distinction may lead to an operation in which a fecally incontinent constipated child is changed to one without an adequate reservoir and a tendency to have loose stool, which is much more difficult to manage. Unfortunately, this is what happened to many ARM patients who were initially treated by abdominoperineal and/ or endorectal pullthrough operations [14] used commonly before the introduction of the PSARP. Loss of the rectal reservoir (Fig. 3B) led many of these children to lose their potential for continence, making them dependent on enemas [15]. Greater understanding and appreciation of this fact, along with widespread practice of the posterior sagittal approach, has considerably reduced the frequency of this outcome [20]. It still occurs, however, when similar operations are undertaken in attempts to treat severe constipation. Faced with severe or recurrent constipation in a child with an ARM, some physicians suspect Hirsch-
M.A. Levitt et al. sprung's disease and, as noted, obtain rectal biopsies to rule out this possibility. Some even proceeded with rectosigmoid resections. Unfortunately, this leads to loose stools and fecal incontinence [15]. We believe that, in the absence of characteristic contrast studies or episodes of enterocolitis, the likelihood of Hirschsprung's disease in conjunction with a known anorectal malformation is very low and does not warrant biopsy or rectosigmoid resection [8]. Other clinicians attempted to treat “unmanageable” constipation with antegrade enemas through a catheterizable stoma or button device [21,22]. We have found, though, that once their constipation is effectively treated medically with laxatives, patients can become continent and turn out not to need washouts at all. We reserve antegrade enemas procedures for incontinent patients who require a daily washout [11]. Despite the limitations of this review, mainly owing to the fact that the referred patients are a non-representative group, as they are referred because they are having problems, the trends we have documented are clear. We regard these morbidities as mostly preventable, despite the fact that some were present in our own patients. In our group, morbidities were mainly related to the patient having rectosigmoid dilation starting at birth, or from inadequate follow up. With an aggressive constipation avoidance and treatment protocol, we were able to see a lower rate of morbidity. The morbidity of constipation in ARM is an impressive list, including impaction, megacolon, pseudoincontinence, and performance of unindicated or unnecessary surgeries. In addition to inadequate treatment, other preventable causes include type and location of the original colostomy (transverse and loop colostomies) postoperative stricture and delayed treatment of a narrow perineal or vestibular fistula. Noncompliance or poor follow-up also contributes to increased morbidity from constipation. It is imperative to understand that children with anorectal malformations with the best prognosis for bowel control are at the greatest risk for severe constipation and its consequences. With appropriate recognition and aggressive, proactive treatment, these morbidities can be significantly reduced.
References [1] Levitt MA, Peña A. Imperforate anus and cloacal malformations. In Pediaric Surgery, 5th ed, Holcomb GW & Murphy JP (editors) Elsevier Saunders, Philadelphia. pp. 337-59 [In Press]. [2] Heinen F. The surgical treatment of low anal defects and vestibular fistulas. Semin Pediatr Surg 1997;64:204-16. [3] Rintala R. Fecal incontinence in anorectal malformations, neuropathy, and miscellaneous conditions. Semin Pediatr Surg 2002;11: 75-82. [4] Rintala R, Lindahl H, Rasanen M. Do children with repaired low anorectal malformations have normal bowel function? J Pediatr Surg 1997;32:823-6. [5] Pakarinen M, Koivusalo A, Lindahl H, et al. Prospective controlled long-term follow-up for functional outcome after anoplasty in boys with perineal fistula. J Pediatr Gastroenterol Nutr 2007;44:436-9.
The morbidity of constipation in patients with anorectal malformations [6] Keshtgar A, Ward H, Richards C, et al. Outcome of excision of megarectum in children with anorectal malformation. J Pediatr Surg 2007;42:227-33. [7] Peña A, El-Behery M. Megasigmoid: a Source of pseudo-incontinence in children with repaired anorectal malformations. J Pediatr Surg 1993; 28:1-5. [8] Peña A, Levitt MA. Colonic inertia disorders in pediatrics. Curr Probl Surg 2002;39:661-732. [9] Smith E. The identification and management of anorectal anomalies— the factors ensuring continence. Prog Pediatr Surg 1976;9:7-40. [10] Kim H, Gow K, Penner J, et al. Presentation of low anorectal malformations beyond the neonatal period. Pediatrics 2000;105:e68. [11] Levitt MA, Peña A. Update on pediatric fecal incontinence. Eur J Pediatr Surg 2009;19:1-9. [12] Kiesewetter W, Sukarochana K, Sieber W. The frequency of aganglionosis associated with imperforate anus. Surg 1965;58: 655-71. [13] Stevenson J, Herron P. Hirschsprung's disease: a rare cause of constipation in patients following surgical correction of imperforate anus: report of 2 cases. Am Surg 1967;33:555-8. [14] Kiesewetter W. Imperforate anus: the role and results of the sacroabdomino-perineal operation. Ann Surg 1966;164:655-61. [15] Bischoff A, Levitt M, Bauer C, et al. Treatment of fecal incontinence with a comprehensive bowel management program. J Pediatr Surg 2009;6:1278-84. [16] Holschneider A, Koebke J, Meier-Ruge W, et al. Pathophysiology of chronic constipation on anorectal malformations. Long-term results and preliminary anatomical investigations. Eur J Pediatr Surg 2001;11: 305-10. [17] Stephens F. Rectal ectasia: primary and secondary associated with anorectal anomalies. Birth Defects Org Artic Ser 1988;24:99-104. [18] Nixon H. An experimental study of propulsion in isolated small intestine and applications to surgery in the newborn. Ann R Coll Surg Engl 1960;27:105-24. [19] Peña A, Migotta-Krieger M, Levitt MA. Colostomy in anorectal malformations: a procedure with serious but preventable complications. J Pediatr Surg 2006;41:748-56. [20] Holschneider A, Pfrommer W, Gerresheim B. Results in the treatment of anorectal malformations with special regard to the histology of the rectal pouch. Eur J Pediatr Surg 1994;4:303-9. [21] Malone P, Ransley P, Kiely E. Preliminary report: the antegrade continence enema. Lancet 1990;336:1217-8. [22] Rakic S, Baeten C. Laparoscopic appendicostomy with cecoplication for antegrade colonic enema procedure. Surg Laparosc Endosc Percutan Tech 2004;14:165-6.
Discussion Gail Besner, MD (Columbus, OH): Could you comment on the three patients that were referred to you from elsewhere who had pull-through procedures that were not indicated? Marc Levitt, MD (Cincinnati, OH) (response): These patients had severe constipation as their only symptom.
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These are patients that underwent biopsies. Those biopsies were done too low so there may have been “absence of ganglion cells”, but there was no comment on whether the nerves are hypertrophic or not. Those patients ultimately underwent rectosigmoid resections and pullthroughs, and sadly, those patients became incontinent because of the hypermotility induced by that resection. Obviously, they didn't have the greatest anal canal or sphincter by nature of their anorectal malformation and could not handle the hypermotility. This is something that needs to be avoided. These patients did not have Hirschprung's disease. Daniel Von Allmen Md (Cincinnati, Ohio): Do you think there was a selection bias since the patients who were referred may have been more complex? Marc Levitt, MD (response): I believe that this is certainly a factor. We do not intend in any way to compare the two groups. These are obviously complex patients. We have no idea what the denominator is. My only point of utilizing the two groups was to show that with an aggressive management scheme from colostomy closure on, you can dramatically reduce the morbidity. Even in the group managed in our institution, we did not come close to zero, there was still a significant amount of morbidity, but you can dramatically reduce it if you're very aware of it and treat it aggressively. Don Nakayama, MD (Macon, Ga): What kind of laxatives do you use on your patients? Marc Levitt, MD (response): We use senna-based laxatives. Most of the things on the market are actually stool softeners, and we regularly stop the stool softeners and change them over to something with a stimulant component, something with senna, I think in these patients, the problem is not hard stool but rather motility of the colon. So giving them a stool softener just makes the stool soft, it doesn't really help it come out, and they have a colon full of stool that doesn't empty, and in fact, may empty in more of a leakage kind of way and they're worse. Many patients will tell you that they're much worse on a stool softener such as MiraLAX; once you put them on something stimulating, it actually empties the distal part of the colon and they do a lot better. It's important to remember that distinction. We routinely are stopping stool softeners and switching patients to laxatives.