Long-term outcome after internal sphincter myectomy for internal sphincter achalasia

Evaluation and Management of Postsurgical Patient With Hirschsprung Disease Neurogastroenterology & Motility Committee: Position Paper of North American Society of Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN)

Children with Hirschsprung disease have postoperative long-term sequelae in defecation that contribute to morbidity and mortality and significantly impact their quality of life. Pediatric patients experience ongoing long-term defecation concerns, which can include fecal incontinence (FI) and postoperative obstructive symptoms, such as constipation and Hirschsprung-associated enterocolitis. The American Pediatric Surgical Association has developed guidelines for management of these postoperative obstructive symptoms and FI. However, the evaluation and management of patients with postoperative defecation problems varies among different pediatric gastroenterology centers. This position paper from the Neurogastroenterology & Motility Committee of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition reviews the current evidence and provides suggestions for the evaluation and management of postoperative patients with Hirschsprung disease who present with persistent defecation problems.

Reoperative techniques and management in Hirschsprung disease: a narrative review

The majority of children who undergo operative management for Hirschsprung disease have favorable results. A subset of patients, however, have long-term dysfunctional stooling, characterized by either frequent soiling or obstructive symptoms. The evaluation and management of a child with poor function after pull-through for Hirschsprung disease should be conducted by an experienced multidisciplinary team. A systematic workup is focused on detecting pathologic and anatomic causes of pull-through dysfunction. This includes an exam under anesthesia, pathologic confirmation including a repeat biopsy, and a contrast enema, with additional studies depending on the suspected etiology. Obstructive symptoms may be due to technique-specific types of mechanical obstruction, histopathologic obstruction, or dysmotility-each of which may benefit from reoperative surgery. The causes of soiling symptoms include loss of the dentate line and damage to the anal sphincter, which generally do not benefit from revision of the pull-through, and pseudo-incontinence, which may reveal underlying obstruction. A thorough understanding of the types of complications associated with various pull-through techniques aids in the evaluation of a child with postoperative dysfunction. Treatment is specifically tailored to the patient, guided by the etiology of the patient's symptoms, with options ranging from bowel management to redo pull-through procedure. This review details the workup and management of patients with complications after pull-through, with a focus on the perioperative management and technical considerations for those who require reoperation.

Impact of Botulinum Toxin on Hirschsprung-Associated Enterocolitis After Primary Pull-Through

BACKGROUND

Hirschsprung-associated enterocolitis (HAEC) is a serious potential complication after primary pull-through surgery for Hirschsprung's disease (HSCR). Administration of anal botulinum toxin (BT) injection may improve obstructive symptoms at the internal anal sphincter, leading to improved fecal passage. The timing of administration and effects on delay or prevention of HAEC are unknown. We hypothesized that BT administration increased the postoperative time to HAEC and aimed to investigate whether anal BT administration after primary pull-through surgery for HSCR is associated with increased time to inpatient HAEC admission development.

METHODS

We performed a retrospective cohort study examining children with HSCR at US children's hospitals from 2008 to 2018 using the Pediatric Health Information System database with an associated primary pull-through operation performed before 60 d of age. The intervention assessed was the administration of BT concerning the timing of primary pull-through, and two groups were identified: PRO (received BT at or after primary pull-through, before HAEC) and NOT (never received BT, or received BT after HAEC). The primary outcome was time from pull-through to the first HAEC admission. The Cox proportional hazards model was developed to examine the BT administration effect on the primary outcome after controlling for patient-level covariates.

RESULTS

We examined a total of 1439 children (67 in the PRO and 1372 in the NOT groups). A total of 308 (21.4%) developed at least one episode of HAEC, including 76 (5.3%) who had two or more episodes. Between 2008 and 2018, the frequency of BT administration has increased from three to 20 hospitals with a frequency of administration between 2.2% and 16.2%. Prophylactic BT (PRO) was not associated with increased time to HAEC event on adjusted analysis.

CONCLUSIONS

Among children with HSCR undergoing primary pull-through surgery, prophylactic BT administration did not demonstrate increased time to first HAEC event. A better-powered study with prophylactic BT is required to determine the effect on HAEC occurrence and timing.

LEVEL OF EVIDENCE

Level II (retrospective cohort study).

Postoperative Pullthrough Obstruction in Hirschsprung Disease: Etiologies and Diagnosis

Some patients continue to have obstructive symptoms and/or incontinence after pullthrough surgery for Hirschsprung disease. Incontinence can be due to injury to the anal sphincter and/or dentate line, abnormal colonic motility (nonretentive), or a chronic large stool burden (retentive). A diagnostic algorithm based on clinical and pathological evaluations can be applied to distinguish potential etiologies for obstructive symptoms, which segregate into anatomic (mechanical or histopathological) or physiologic subgroups. Valuable clinical information may be obtained by anorectal examination under anesthesia, radiographic studies, and anorectal or colonic manometry. In addition, histopathological review of a patient's original resection specimen(s) as well as postoperative biopsies of the neorectum usually are an important component of the diagnostic workup. Goals for the surgical pathologist are to exclude incomplete resection of the aganglionic segment or transition zone and to identify other neuromuscular pathology that might explain the patient's dysmotility. Diagnoses established from a combination of clinical and pathological data dramatically alter management strategies. In rare instances, reoperative pullthrough surgery is required, in which case the pathologist must be aware of histopathological features specific to redo pullthrough resection specimens.

Botulinum toxin injection for internal anal sphincter achalasia after pull-through surgery in Hirschsprung disease

Botulinum toxin (Botox) was introduced for the management of internal anal sphincter (IAS) achalasia after a pull-through procedure in Hirschsprung disease (HD). We conducted a prospective evaluation of the efficacy and safety of this Botox treatment.Our study group included 15 patients with HD (median age, 4.8 years; range, 1.7-7.4 years) who experienced persistent constipation after pull-through surgery. Rectal biopsy and colon study were performed before Botox injection to exclude agangliosis. Intersphincteric Botox injections (dose, 4 IU/kg) were performed at 3 sites, (3, 6, and 9 o'clock) under general anesthesia. Measured outcomes of efficacy included anorectal manometry, Wexner constipation score and the quality of life score for defecation, measured at baseline and at 2 weeks and 3 months after injection. The Holschneider incontinence score and an assessment of pain, bleeding, heating sensation, and swelling were also performed at follow-up as outcomes of safety.There was no significant change in measured outcomes with Botox treatment. Botox did decrease the number of patients who experienced abdominal distension at 3 months, compared to 2-weeks, post-injection. No major complications were identified, with only 2 cases of anal bleeding that resolved spontaneously. Local tenderness at the injection site was reported by 4 patients, recovering without treatment.The efficacy of Botox, injected into the IAS, for the treatment of achalasia is questionable on short-term follow-up. Larger studies with a longer follow-up period and the use of repeated injections are required to evaluate the evidence for this treatment.

Prevention and management of recurrent postoperative Hirschsprung's disease obstructive symptoms and enterocolitis: Systematic review and meta-analysis

BACKGROUND/PURPOSE

The purpose of this study was to review the management of obstructive symptoms and enterocolitis (HAEC) following pull-through for Hirschsprung's disease.

METHODS

A systematic review and meta-analysis (1992-2017) was performed. Included studies were: randomized controlled trials (RCT), retrospective/prospective case-control (C-C), case-series (C-S). Random-effect model was used to produce risk ratio (RR) [95% CI]. P < 0.05 was considered significant.

RESULTS

Twenty-nine studies were identified. Routine postoperative dilatations (5 C-S, 2 C-C; 405 patients): no effect on stricture incidence (RR 0.3 [0.02-5.7]; p = 0.4). Routine postoperative rectal irrigations (2 C-C; 172 patients): reduced HAEC incidence (RR 0.2 [0.1-0.5]; p = 0.001). Posterior myotomy/myectomy (4 C-S; 53 patients): resolved obstructive symptoms in 79% [60.6-93.5] and HAEC in 80% [64.1-92.1]. Botulinum toxin injection (9 C-S; 166 patients): short-term response in 77.3% [68.2-85.2], long-term response in 43.0% [26.9-59.9]. Topical nitric oxide (3 C-S; 13 patients): improvement in 100% of patients. Probiotic prophylaxis (3 RCT; 160 patients): no reduction in HAEC (RR 0.6 [0.2-1.7]; p = 0.3). Anti-inflammatory drugs (1 C-S, sodium cromoglycate; 8 patients): improvement of HAEC in 75% of patients.

CONCLUSIONS

Several strategies with variable results are available in patients with obstructive symptoms and HAEC. Routine postoperative dilatations and prophylactic probiotics have no role in reducing the incidence of postoperative obstructive symptoms and HAEC.

TYPE OF STUDY

Systematic review and meta-analysis.

LEVEL OF EVIDENCE

Level II.

Botulinum toxin injection for childhood constipation is safe and can be effective regardless of anal sphincter dynamics

BACKGROUND

Childhood constipation is common. Previously, internal anal sphincterotomy has been used for hypertensive/non-relaxing sphincters; however, recent benefit has been shown with Botulinum Toxin (BT) injections. The aim is to investigate BT, including response duration, symptom association and effectiveness in relation to sphincter dynamics.

METHODS

Retrospective study of 164 children receiving sphincter BT for severe constipation unresponsive to medication management. Charts reviewed for symptoms, anorectal manometry (ARM) findings and response defined by decreased pain or increased defecation. Patients were grouped: normal sphincter pressure (≤50 mmHg), elevated (>50 mmHg), normal and abnormal rectoanal inhibitory reflex (RAIR).

RESULTS

There were 142 analyzed and 124 completed ARMs; 98 (70%) had positive response with 57% lasting greater than 6 months. 36 had normal sphincter pressure with 24 (69%) responding. 88 had elevated pressure with 60 (68%) responding (p=0.87). 90 normal RAIRs with 64 (71%) responding. 34 abnormal RAIRs with 22 (64%) responding (p=0.41). With logistic regression, fecal incontinence prior to BT was a predictor of poor response (p= 0.02). The most common side effect was fecal incontinence typically resolving within week with equal frequency regardless of sphincter dynamics.

CONCLUSIONS

BT is effective for children with chronic constipation. Patients with fecal incontinence are less likely to respond. More than half had prolonged beneficial response. Those with normal and abnormal sphincter dynamics had similar responses and without differences in side effects. Therefore, injection may be considered in patients with intractable constipation unresponsive to medication, regardless of anal sphincter dynamics.

LEVEL OF EVIDENCE

Level III (Treatment Study: Retrospective comparative study).

Ultrasound-guided intrasphincteric botulinum toxin injection relieves obstructive defecation due to Hirschsprung's disease and internal anal sphincter achalasia

PURPOSE

Chronic obstructive defecation can occur in patients with Hirschsprung Disease (HD) and internal anal sphincter (IAS) achalasia. Injection of Botulinum Toxin (BoTox) into the IAS can temporarily relieve obstructive defecation, but can be challenging when performed by tactile sense alone. We compared results of BoTox injections with and without ultrasound (US) guidance.

METHODS

We retrospectively reviewed BoTox injections into the IAS for obstructive defecation over 5years. Analyzed outcomes included short-term improvement, defined as resolution of enterocolitis, new ability to spontaneously defecate, and/or normalization of bowel movement frequency 2weeks post-operatively, as well as requirement of more definitive surgical therapy (myotomy/myomectomy, colectomy, colostomy, cecostomy/appendicostomy, and/or sacral nerve stimulator implantation). Outcomes were compared using t-test and Fisher's Exact test, with significance defined as p<0.05.

RESULTS

Twelve patients who underwent BoTox injection were included, including 5 patients who underwent injections both with and without ultrasound. Ten underwent an ultrasound-guided injection (13 injection procedures), 5 of whom had HD. Seven underwent an injection without ultrasound guidance (17 injection procedures), 5 of whom had HD. Procedures performed with US resulted in greater short-term improvement (76% versus 65% without ultrasound) and less requirement of a definitive procedure for obstructive defecation (p<0.05).

CONCLUSIONS

US-guided BoTox injection is safe and effective for obstructive defecation, and may decrease the need for a definitive operation.

LEVEL OF EVIDENCE

III.

RESULTS OF POSTERIOR MYECTOMY FOR THE TREATMENT OF CHILDREN WITH CHRONIC CONSTIPATION

BACKGROUND AND OBJECTIVES

The aim of this study was to evaluate the result of posterior myectomy in children with chronic constipation who underwent to this surgery.

METHODS

Forty eight children with chronic constipation who did not respond to diet, laxative, or enema were included. Children with abnormal barium enema showing transitional zone were excluded. Children with documented metabolic disease diabetes, and hypothyroidism were also excluded. All patients underwent posterior myectomy. Children were followed during 1 year after surgery regarding frequency of fecal evacuation, fecal consistency, straining during defecation, and diameter of feces. Data was analyzed using SPSS version 13.0 (Chicago, IL, USA).

RESULTS

Of 48 cases that underwent surgery, 21 were male and 27 were female. Age range was 1.5 to 11 years old. Mean duration of constipation before surgery was 22.79±17.08 (range 6-48 months). Mean duration of medical treatment was 14.90±10.31 (range= 6-48 months). Fecal consistency, feces diameter, number of bowel movements and straining during defecation were compared before and after surgery. The results were statistically significant ( P <0.001). Of all cases, 52% continued treatment of constipation after surgery for 1 year. Ganglion cells were absent in 32 cases. Ganglion cells were present in seven children. Proximal ganglion cell was found in nine cases Treatment response was not different between cases according to status of ganglion cell in biopsy.

CONCLUSION

Fecal consistency, feces diameter, number of bowel movements, and straining for defecation were improved after posterior myectomy. Another study with more sample is required for better evaluation of treatment.

Botulinum toxin is efficient to treat obstructive symptoms in children with Hirschsprung disease

BACKGROUND

Obstructive symptoms are common after pull-through for Hirschsprung disease. Botulinum toxin injection treatment may improve the bowel function if internal sphincter achalasia is the cause of obstructive symptoms. The aim of this study was to review the outcome in patients treated with intrasphincteric botulinum toxin injections after pull-through for Hirschsprung disease.

METHODS

The operative records were used to identify children with Hirschsprung disease who were treated with botulinum toxin injections at Karolinska University Hospital, Stockholm, Sweden, from September 2007 to November 2014. Data on age, sex, associated syndromes, length of aganglionic segment, age at pull-through, type of pull-through, age at first botulinum toxin injection, indication for botulinum toxin injection, and effect of first botulinum toxin injection were retrieved from the case records. Bowel function at last follow-up visit or telephone contact was recorded.

RESULTS

Nineteen patients were identified. All had biopsy-verified Hirschsprung disease. Eighteen (15 males and 3 females) children had undergone intrasphincteric botulinum toxin injection treatment for obstructive symptoms after pull-through, which was done at 127 (18-538) days of age. Four children had total colonic aganglionosis. The first botulinum toxin injection was given at 2.4 (0.53-6.9) years of age. Thirteen children (72 %) had a good response to the first injection treatment. The children underwent 3 (1-13) injection treatments. At follow-up four patients had improved and did not need treatment for obstruction, four were scheduled for further botulinum toxin injections, eight had persistent obstructive symptoms treated with laxatives or enemas, and two children had an ileostomy.

CONCLUSION

Botulinum toxin injection treatment improves the obstructive symptoms in children after pull-through for Hirschsprung disease. The effect is reversible and a majority of patients need repeat injections. When injection treatment is not repeated, a large proportion of children need laxatives or enemas due to recurrent symptoms.

Outcome after anal intrasphincteric Botox injection in children with surgically treated Hirschsprung disease

OBJECTIVES

A nonrelaxing internal anal sphincter is present in a relatively large proportion of children with surgically treated Hirschsprung disease (HD) and can cause obstructive gastrointestinal symptoms. The short- and long-term outcome and adverse effects of intrasphincteric botulinum toxin (Botox) injections in children with obstruction after surgically treated HD are evaluated.

METHODS

The outcome of children with surgically treated HD treated with intrasphincteric Botox injections for obstructive symptoms was analyzed with a retrospective chart review between 2002 and 2013 in the University Medical Centers of Maastricht and Nijmegen.

RESULTS

A total of 33 patients were included. The median time of follow-up was 7.3 years (range 1-24). A median of 2 (range 1-5) injections were given. Initial improvement was achieved in 76%, with a median duration of 4.1 months (range 1.7-58.8). Proportion of children hospitalized for enterocolitis decreased after treatment from 19 to 7. A good long-term response was found in 49%. Two children experienced complications: transient pelvic muscle paresis with impairment of walking. In both children symptoms resolved within 4 months without treatment.

CONCLUSIONS

Intrasphincteric Botox injections in surgically treated HD are an effective long-term therapy in approximately half of our patients with obstructive symptoms. The possibility of adverse effects should be noticed.

Effect of propofol on anal sphincter pressure during anorectal manometry

We evaluated the effect of propofol on resting anal sphincter pressure (RP) during anorectal manometry performed under general anesthesia in 20 children with chronic constipation. After propofol bolus administration, there was a significant decrease in the RP in 95% of children from a mean of 51.5 ± 15.3 to a mean nadir of 21.7 ± 10.5 mmHg (P < 0.001). The new postpropofol RP of 47.0 ± 12.4 mmHg was significantly lower compared with prepropofol RP (P < 0.0001). Propofol should be used with caution as an anesthetic agent for anorectal manometry, given the potential for confounding RP measurements.

Classification and diagnostic criteria of variants of Hirschsprung's disease

"Variants of Hirschsprung's disease" are conditions that clinically resemble Hirschsprung's disease (HD), despite the presence of ganglion cells in rectal suction biopsies. The diagnosis and management of these patients can be challenging. Specific histological, immunohistochemical and electron microscopic investigations are required to characterize this heterogeneous group of functional bowel disorders. Variants of HD include intestinal neuronal dysplasia, intestinal ganglioneuromatosis, isolated hypoganglionosis, immature ganglia, absence of the argyrophil plexus, internal anal sphincter achalasia and congenital smooth muscle cell disorders such as megacystis microcolon intestinal hypoperistalsis syndrome. This review article systematically classifies variants of HD based on current diagnostic criteria with an additional focus on pathogenesis, epidemiology, clinical presentation, management and outcome.

Hirschsprung-associated enterocolitis: pathogenesis, treatment and prevention

Hirschsprung-associated enterocolitis (HAEC) is a common and sometimes life-threatening complication of Hirschsprung disease (HD). Presenting either before or after definitive surgery for HD, HAEC may manifest clinically as abdominal distension and explosive diarrhea, along with emesis, fever, lethargy, and even shock. The pathogenesis of HAEC, the subject of ongoing research, likely involves a complex interplay between a dysfunctional enteric nervous system, abnormal mucin production, insufficient immunoglobulin secretion, and unbalanced intestinal microflora. Early recognition of HAEC and preventative practices, such as rectal washouts following a pull-through, can lead to improved outcomes. Treatment strategies for acute HAEC include timely resuscitation, colonic decompression, and antibiotics. Recurrent or persistent HAEC requires evaluation for mechanical obstruction or residual aganglionosis, and may require surgical treatment with posterior myotomy/myectomy or redo pull-through. This chapter describes the incidence, pathogenesis, treatment, and preventative strategies in management of HAEC.

Reoperative surgery for Hirschsprung disease

Despite most children undergoing a successful pull through for Hirschsprung disease, a small portion of children are left with persistent stooling issues. Most of these stooling issues can be addressed by nonoperative approaches. However, in a small group of remaining children, a reoperation may be necessary. Most children who may need a redo pull-through procedure may have a persistent area of aganglionosis, unremitting enterocolitis, or a torsion or stricture of the pull-through segment. Each of these influences the approach the surgeon must take to correct the presenting problem. The chapter details the diagnostic approach as well as the operative techniques, which best deal with each of these complications.

Hirschsprung-associated enterocolitis: prevention and therapy

Hirschsprung-associated enterocolitis remains the greatest cause of morbidity and mortality in children with Hirschsprung disease. This chapter details the various approaches used to treat and prevent this disease process. This includes prevention of complications, such as stricture formation, prophylaxis with rectal washouts, and identification of high-risk individuals. The chapter also details approaches to diagnose Hirschsprung-associated enterocolitis as well as to exclude other etiologies.

Comparison of posterior internal anal sphincter myectomy and intrasphincteric botulinum toxin injection for treatment of internal anal sphincter achalasia: a meta-analysis

PURPOSE

Internal anal sphincter (IAS) achalasia is a clinical condition with presentation similar to Hirschsprung's disease, but with the presence of ganglion cells on rectal suction biopsy (RSB). The diagnosis is made by anorectal manometry (ARM), which demonstrates the absence of the rectosphincteric reflex on rectal balloon inflation. The recommended treatment of choice is posterior IAS myectomy. Recently, intrasphincteric botulinum toxin (Botox) injection has been effectively used for treatment of IAS achalasia. The aim of this meta-analysis was to compare the efficacy of posterior IAS myectomy with intrasphincteric Botox injection for treatment of IAS achalasia.

METHODS

A systematic literature search for relevant articles was conducted using the following databases: MEDLINE( ® ), EMBASE(®), ISI Web of Science(SM) and the Cochrane Library. A meta-analysis was performed with the studies where IAS achalasia was diagnosed based on the results of ARM and RSB. Odds ratio (OR) with 95 % confidence intervals were calculated.

RESULT

Sixteen prospective and retrospective studies, published from 1973 to 2009, were identified. A total of 395 patients with IAS achalasia were included in this meta-analysis. Fifty-eight percent of patients underwent IAS myectomy and 42 % Botox injection. Regular bowel movements were significantly more frequent after IAS myectomy (OR 0.53, [95 % CI 0.29-0.99]; p = 0.04). There was no significant difference in continued use of laxatives or rectal enemas (OR 0.92, [95 % CI 0.34-2.53], p = 0.89) and in overall complication rates between both procedures (OR 0.68, [95 % CI 0.38-1.21]; p = 0.19). Looking at specific complications, the rate of transient faecal incontinence was significantly higher after Botox injection (OR 0.07, [95 % CI 0.01-0.54]; p < 0.01). Constipation and soiling were not significantly different between both procedures (OR 0.66, [95 % CI 0.30-1.48]; p = 0.31 and OR 0.24, [95 % CI 0.03-2.07]; p = 0.25). The rate of non-response was significantly higher after Botox injection (OR 0.52, [95 % CI 0.27-0.99]; p = 0.04). Subsequent surgical treatment was significantly more frequent after Botox injection (OR 0.18, [95 % CI 0.07-0.44]; p < 0.0001). Short- and long-term improvements were significantly more frequent after IAS myectomy (OR 0.56, [95 % CI 0.32-0.97]; p = 0.04 and OR 0.25, [95 % CI 0.15-0.41]; p < 0.0001).

CONCLUSION

This meta-analysis indicates that in patients with IAS achalasia, posterior IAS myectomy appears to be a more effective treatment option compared to intrasphincteric Botox injection. After Botox injection, the rate of transient faecal incontinence, non-response and subsequent surgical procedures were significantly higher compared to IAS myectomy.

A comparison of clinical protocols for assessing postoperative fecal continence in anorectal malformation

BACKGROUND

We compared four protocols for assessing fecal continence (FC) in anorectal malformation (ARM).

METHODS

Of 111 ARM cases we treated by anoplasty from 1995 to 2007, 59 have been followed up for more than 4 years [male high (n = 23), male low (n = 12), female high (n = 7), and female low (n = 17)] and 27 for more than 7 years [male high (n = 11), male low (n = 5), female high (n = 5), and female low (n = 6)]. FC was assessed in these 86 cases using each of the four protocols; the Kelly score (0-6 points), the Japanese Study Group of Anorectal Anomalies (JSGA) score (0-8 points), the Holschneider score (0-14 points), and our original score (0-10 points). Results were re-classified into four outcome levels (good, fair, poor, very poor) for direct comparison.

RESULTS

Outcome was different by two levels (i.e., good vs. very poor) in 7 (8.1%) assessments and different by one category (i.e., fair vs. poor) in ten assessments (11.6%). Outcome was different most often in male high ARM cases and JSGA scores were most divergent.

CONCLUSIONS

Fecal continence in male high ARM appears to be assessed inconsistently and a review of protocols may be of value to standardize clinical assessment and enhance reliability.

Internal anal sphincter achalasia

Internal anal sphincter (IAS) achalasia is a clinical condition with presentation similar to Hirschsprung's disease, but with the presence of ganglion cells on rectal suction biopsy. The diagnosis is made by anorectal manometry, which demonstrates the absence of the rectosphincteric reflex on rectal balloon inflation. The IAS is regulated by several neurogenic mechanisms, and so its pathogenesis is thought to be multifactorial, including the absence of nitrergic innervations, defective innervation of the neuromuscular junction, and altered distribution of interstitial cells of Cajal. The recommended treatment of choice is posterior IAS myectomy. Recently, however, the use of intrasphincteric botulinum toxin has been used to treat this condition, but further long-term studies are needed to determine its effectiveness.

Long-term outcome of internal sphincter myectomy in patients with internal anal sphincter achalasia

BACKGROUND

Internal anal sphincter achalasia (IASA) is a condition with presentation similar to Hirschsprung's disease (HD), but with the presence of ganglion cells on rectal suction biopsy (RSB). The diagnosis is made on anorectal manometry (ARM) by the absence of the rectosphincteric reflex on rectal balloon inflation. Internal sphincter myectomy (ISM) is the treatment of choice for patients with IASA. Recently, botulinum toxin has been used to treat IASA patients. The purpose of this study was to assess the long-term bowel function in patients with IASA following ISM.

METHODS

The medical records of 24 patients with IASA managed by ISM during 1993-2005 were examined. There were 18 boys and 6 girls, aged 2-12 years. All patients presented with intractable constipation with or without soiling. The diagnosis was made by the demonstration of the absence of the rectosphincteric reflex on ARM. HD was excluded by the presence of ganglion cells and normal acetylcholinesterase activity in RSB. Patients were followed 4-14 years later.

RESULTS

Fifteen (62.5%) patients at the time of follow-up had regular bowel motions without the use of laxatives. Six (25%) patients had regular bowel motions, but remained on small doses of laxatives. Two (8.3%) patients who suffered from constipation and soiling required twice weekly enemas to remain clean. One (4.2%) patient required resection of dilated rectosigmoid colon 3 years after myectomy, remains on laxatives, but has normal bowel control. No patients had faecal incontinence following ISM.

CONCLUSION

This long-term follow-up study shows that the vast majority of IASA patients have normal bowel control following ISM.

Botox injection treatment for anal outlet obstruction in patients with internal anal sphincter achalasia and Hirschsprung's disease

BACKGROUND AND AIM

Botox injection treatment (BIT) is a potentially effective but yet unproven treatment of functional anal outlet obstruction that is caused by non-relaxing internal anal sphincter. We present a single institution experience of BIT from 2005 to 2008.

PATIENTS AND METHODS

Sixteen patients (11 males), eight with Hirschsprung's disease (HD) (one with total colon aganglionosis, TCA) and eight with internal sphincter achalasia (ISA) were included. Median ages were 3.8 years (0.4-9.3) for HD and 8.1 years (range 1.5-11.4) for ISA. ISA was defined as the absence of rectoanal inhibitory reflex with normal rectal biopsies. Seven HD patients had previous coloanal pull-through (CAPT), and one (TCA) colectomy and ileoanal J-Pouch anastomosis. Two of the ISA patients had undergone internal sphincter myectomy and two had Malone procedure [antegrade colonic enema (ACE)]. Indication for BIT in 16 patients was anal outlet obstruction (n = 11) with soiling and recurring HD-associated enterocolitis (n = 5) and in one patient (HD, TCA) soiling with enterocolitis (n = 1). Before BIT, all patients underwent anorectal manometry, rectal biopsies and barium enema. The effect of BIT was evaluated after 2 months and BIT was repeated if necessary. Effect of BIT was scored as follows: 0 no, 1 little, 2 significant effect and 3 symptoms disappeared.

RESULTS

Median follow-up was 19 months (range 3-43). The median number of injections was two per patient (range 1-4) and the median Botox dose was 80 U (range 40-100). Scores of BIT effect were 3 or 2 in five (31%) and 0 or 1 in 11 (69%). After adjunctive treatment modalities (myectomy n = 1, CAPT n = 1, adjusted ACE/laxative treatment), the end result was good or satisfactory in 11 (69%) but remained poor in 5 (31%) patients. Patient age, diagnosis, anorectal resting pressure or findings in barium enema were not correlated with BIT efficiency score (R range -0.06 to 0.39, P = 0.12-0.91).

CONCLUSION

Although successful in some patients, the role of BIT remains undetermined. It is difficult to predict which patients will profit from BIT. Continuing other treatment modalities after BIT may improve the results.

Long-term clinical outcome after botulinum toxin injection in children with nonrelaxing internal anal sphincter

OBJECTIVES

Children with surgically repaired Hirschsprung's disease (HD) and those with internal anal sphincter (IAS) achalasia may develop obstructive gastrointestinal symptoms and/or enterocolitis due to a functional obstruction caused by an inability of the IAS to relax. Anal sphincter Clostridium botulinum toxin (BoTox) injections may provide a reversible therapy. However, there is limited information regarding the long-term outcomes of children receiving this therapy. The primary aim of this study was to determine the long-term clinical outcomes of BoTox therapy in children with a nonrelaxing IAS. The secondary aim of this study was to determine prognostic factors predicting a favorable outcome following BoTox IAS injection.

METHODS

We conducted a retrospective review of children with nonrelaxing IAS who received anal sphincter BoTox at a tertiary medical center. Children were classified into one of four long-term clinical outcome groups (excellent, good, fair, poor).

RESULTS

A total of 73 children (30 HD, 43 IAS achalasia) received anal sphincter BoTox injections and had a mean follow-up of 32.1+/-2.9 (s.e.) months. A mean of 2.7+/-0.2 injections were given to each child, with 56 (76.7%) children receiving multiple injections. An initial clinical improvement was seen in 65 of 73 (89%) children after the first injection. A total of 39 (53.4%) children had an excellent or good long-term outcome that was maintained for a mean of 17.1+/-3.1 months from the time of the last BoTox injection. Hospitalization rates significantly decreased in those previously hospitalized before initial BoTox injection. Seven (9.5%) patients developed transient fecal incontinence, and one (1.3%) developed significant pain after an injection. Factors predicting a favorable long-term clinical outcome were initial short-term improvement after the first BoTox injection and having IAS achalasia rather than HD.

CONCLUSIONS

Anal sphincter BoTox may be an effective and safe long-term therapy for children with nonrelaxing IAS.

Botulinum toxin for the treatment of chronic constipation in children with internal anal sphincter dysfunction

Internal anal sphincter (IAS) dysfunction is a cause of refractory constipation in children. The goal of this study was to determine whether intrasphincteric injection of botulinum toxin is effective in the treatment of constipation in pediatric patients with IAS dysfunction. A retrospective review was performed of 24 pediatric patients with intractable constipation. All patients had abnormal anorectal manometry, with either elevated IAS resting pressure (> or =100 mm Hg) or an absent or diminished rectoanal inhibitory reflex. Patients with Hirschsprung's disease were excluded. All patients underwent botox injection into the IAS and were followed for a minimum of 6 months. Of 24 patients, 22 experienced significant improvement in their constipation lasting greater than 2 weeks. The duration of effect was variable, with 12 patients demonstrating benefit lasting at least 6 months. Transient postoperative incontinence occurred in five patients. Intrasphincteric injection of botox is a safe and effective treatment for intractable constipation in children with IAS dysfunction.