Hirschsprung's disease. Identification of risk factors for enterocolitis

Approach to Constipation in Children: Recommendations for Evaluation and Management

Constipation is common in childhood, and most patients can be successfully managed by their primary care provider. However, some patients will require more specialized management either due to an underlying congenital colorectal disorder such as Hirschsprung disease or anorectal malformation or due to severe functional constipation that is refractory to medical management.

Risk factors for Hirschsprung disease-associated enterocolitis: a systematic review and meta-analysis

BACKGROUND

The incidence of Hirschsprung disease (HSCR) is nearly 1/5000 and patients with HSCR are usually treated through surgical intervention. Hirschsprung disease-associated enterocolitis (HAEC) is a complication of HSCR with the highest morbidity and mortality in patients. The evidence on the risk factors for HAEC remains inconclusive to date.

METHODS

Four English databases and four Chinese databases were searched for relevant studies published until May 2022. The search retrieved 53 relevant studies. The retrieved studies were scored on the Newcastle-Ottawa Scale by three researchers. Revman 5.4 software was employed for data synthesis and analysis. Stata 16 software was employed for sensitivity analysis and bias analysis.

RESULTS

A total of 53 articles were retrieved from the database search, which included 10 012 cases of HSCR and 2310 cases of HAEC. The systematic analysis revealed anastomotic stenosis or fistula [ I2 =66%, risk ratio (RR)=1.90, 95% CI 1.34-2.68, P <0.001], preoperative enterocolitis ( I2 =55%, RR=2.07, 95% CI 1.71-2.51, P <0.001), preoperative malnutrition ( I2 =0%, RR=1.96, 95% CI 1.52-2.53, P <0.001), preoperative respiratory infection or pneumonia ( I2 =0%, RR=2.37, 95% CI 1.91-2.93, P <0.001), postoperative ileus ( I2 =17%, RR=2.41, 95% CI 2.02-2.87, P <0.001), length of ganglionless segment greater than 30 cm ( I2 =0%, RR=3.64, 95% CI 2.43-5.48, P <0.001), preoperative hypoproteinemia ( I2 =0%, RR=1.91, 95% CI 1.44-2.54, P <0.001), and Down syndrome ( I2 =29%, RR=1.65, 95% CI 1.32-2.07, P <0.001) as the risk factors for postoperative HAEC. Short-segment HSCR ( I2 =46%, RR=0.62, 95% CI 0.54-0.71, P <0.001) and transanal operation ( I2 =78%, RR=0.56, 95% CI 0.33-0.96, P =0.03) were revealed as the protective factors against postoperative HAEC. Preoperative malnutrition ( I2 =35 % , RR=5.33, 95% CI 2.68-10.60, P <0.001), preoperative hypoproteinemia ( I2 =20%, RR=4.17, 95% CI 1.91-9.12, P <0.001), preoperative enterocolitis ( I2 =45%, RR=3.51, 95% CI 2.54-4.84, P <0.001), and preoperative respiratory infection or pneumonia ( I2 =0%, RR=7.20, 95% CI 4.00-12.94, P <0.001) were revealed as the risk factors for recurrent HAEC, while short-segment HSCR ( I2 =0%, RR=0.40, 95% CI 0.21-0.76, P =0.005) was revealed as a protective factor against recurrent HAEC.

CONCLUSION

The present review delineated the multiple risk factors for HAEC, which could assist in preventing the development of HAEC.

Prognostic factors of postoperative Hirschsprung-associated enterocolitis: a cohort study

PURPOSE

To identify prognostic factors of postoperative Hirschsprung-associated enterocolitis (HAEC).

METHOD

A retrospective cohort study of Hirschsprung patients between 2006 and 2021 was conducted. Patients with anorectal malformation and non-definitive surgery were excluded. Associated factors for postoperative HAEC were reported with hazard ratio (HR) and 95% confidence interval (CI).

RESULTS

Forty-nine patients were excluded due to concurrent anorectal malformation and incomplete data. Of 274 patients, 75 patients (27.4%) had at least one episode of postoperative HAEC. There were 28 patients (37.3%) who had multi-episodes of HAEC. The total episodes of post-operative HAEC in this study were 121 episodes (36.8%). In multivariable survival analysis, significant factors associated with postoperative HAEC were the aganglionic level above sigmoid colon (HR = 3.47, p = 0.023, 95% CI 1.19-10.09), and total colonic aganglionosis (HR = 14.83, p = 0.004, 95% CI 2.33-94.40). The patients who experienced clinical enterocolitis before 2 weeks after surgery significantly developed more postoperative HAEC (HR = 5.32, p = 0.038, % CI 1.09-25.92). The incidence of postoperative HAEC was increase in patients with postoperative obstructive symptoms (48.0%). One patient died due to severe sepsis from postoperative HAEC, while three others required intensive care.

CONCLUSIONS

The long involvement of aganglionic segment and early postoperative HAEC was significantly associated with postoperative HAEC. Frequent follow-up, parental education, and early treatment are recommended in these individuals, particularly in the first year after surgery.

Current understanding of Hirschsprung-associated enterocolitis: Pathogenesis, diagnosis and treatment

Hirschsprung-associated enterocolitis (HAEC) was described in 1886 by Harald Hirschsprung and is a potentially deadly complication of Hirschsprung Disease. HAEC is classically characterized by abdominal distension, fever, and diarrhea, although there can be a variety of other associated symptoms, including colicky abdominal pain, lethargy, and the passage of blood-stained stools. HAEC occurs both pre-operatively and post-operatively, is the presenting symptom of HSCR in up to 25% of infants and varies in overall incidence from 20 to 60%. This article reviews our current understanding of HAEC pathogenesis, diagnosis, and treatment with discussion of areas of ongoing research, controversy, and future investigation.

Forty-Year Experience Alleviating Postoperative Hirschsprung-Associated Enterocolitis by Complete Full-Thickness Posterior Rectal Cuff Excision. The Anorectal Line Eliminates Problematic Anastomoses

Introduction: A modified pull-through (PT) distinguished by complete full-thickness removal of the posterior rectal cuff, initially developed as an open procedure in 1980, has been performed with laparoscopic assistance since 1997. Postoperative bowel dysfunction improved when the anatomic landmark for PT surgery was revised from the dentate line (DL) to the anorectal (or Herrmann's) line (ARL) in 2007. A 40-year (1980-2019) review of 153 consecutive rectal/rectosigmoid type Hirschsprung's disease (HD) patients is presented. Methods: Data for postoperative bowel dysfunction and Hirschsprung-associated enterocolitis (HAEC) classified according to the American Pediatric Surgical Association (APSA) scale were obtained retrospectively. Results: PT was open (n = 43) and laparoscopic (n = 110). Dissection was DL (n = 57) and ARL (n = 96). Over 40 years, 5/153 patients (3.3%) had postoperative obstructive symptoms (POS), and 10/153 patients (6.5%) had 13 episodes of postoperative HAEC; APSA grades were: I (n = 4); II (n = 8); and III: (n = 1) presenting with explosive diarrhea (10/13; 76.9%), fever (10/13; 76.9%), abdominal distension (9/13; 69.2%), or bloody stools/shock (1/13 with grade III; 7.7%). The grade III case had histologically-proven transitional zone PT. Postoperative HAEC developed in 3/5 (60.0%) POS+ patients and 7/148 (4.7%) POS- patients (P = .002). Symptom duration and treatment were not correlated with APSA grades. Conclusions: Complete full-thickness posterior rectal cuff excision and using the ARL reduced postoperative HAEC significantly in this series. Despite being anatomically distinct, the DL is inadequate as a precise landmark for PT surgery because it lacks functional relevance. The APSA scale could benefit from timely review to improve its clinical and prognostic value.

Risk factors for enterocolitis in patients with Hirschsprung disease: A retrospective observational study

INTRODUCTION

Hirschsprung-associated enterocolitis (HAEC) accounts for substantial morbidity and mortality in patients with Hirschsprung disease (HD). The aim of this study was to identify incidence of pre- and postoperative HAEC in our consecutive cohort and to identify patient and clinical characteristics that are associated with developing postoperative HAEC and HAEC-free interval.

MATERIAL AND METHODS

A retrospective cohort study was performed with all 146 HD patients treated between 2000 and 2017. Data were retrieved from the medical records. HAEC was defined as presence of clinical signs of bowel inflammation, that required treatment with intravenous antibiotics and admittance to the hospital during at least two days. To identify risk factor for HAEC, patients with and without a history of postoperative HAEC were compared. Kaplan-Meier and Cox-regression were used to assess HAEC free intervals before and after surgery.

RESULTS

Out of 146 patients, 12 patients had pre-operative HAEC (8%) and 31 patients had postoperative HAEC (21%). Median preoperative HAEC free interval was 112 days (IQR 182 days). Length of hospital stay due to readmissions was longer for patients with a history of postoperative HAEC compared to patients without a history of postoperative HAEC (9.5 vs 16 days, U = 1872.5, p = 0.047). Median postoperative HAEC free interval was 226 days. Of the patients who had postoperative HAEC, 66% had their first episode within the first year after surgery and that the incidence of HAEC declined over follow-up.

CONCLUSIONS

HAEC incidence was relatively low in our population. No patient or clinical characteristics were associated with the risk of postoperative HAEC.

Use of an enterocolitis triage and treatment protocol in children with Hirschsprung disease reduces hospital admissions

BACKGROUND

While a consensus for the definition of Hirschsprung associated enterocolitis (HAEC) is lacking, the mainstay of treatment includes rectal irrigations with or without antibiotics. This treatment is often effective when initiated as an outpatient. Our institution implemented a triage algorithm in an effort to standardize care thus providing more timely treatment and preventing unnecessary hospital admissions. We sought to review our short-term experience.

METHODS

A retrospective review was performed of all Hirschsprung (HD) patients <6 years old over two distinct time periods from May 2016-2017 (pre-protocol, group A) and June 2017-2018 (post-protocol, group B). Patients with a colostomy were excluded. Primary end point was hospital admission. Presenting symptoms were categorized as moderate or severe, with patient triage based on number and quality of symptoms.

RESULTS

Eighty-seven total patients were included. Rectosigmoid transition zone was most common (75%) and 20% of patients had trisomy 21. HAEC occurred in 22% of patients in the preprotocol group (group A, n = 78, 27 episodes) and 20% of patients in the post-protocol group (group B, n = 87, 32 episodes). In group A, 78% of episodes required an unplanned visit and 74% resulted in admission. In group B, 81% of episodes required an unplanned visit and 50% resulted in admission (33% reduction in hospital admission, p = 0.06). Irrigations only, without antibiotics, were used in 30% of episodes in group A versus 41% in group B. Of patients who initially contacted the office by phone (group A = 7 episodes, group B = 6 episodes), outpatient management was successful in 43% versus 100% respectively (p = 0.07). No patient experienced increased morbidity in group B.

DISCUSSION

Implementation of a HAEC treatment algorithm shows promise in improving the management and resource utilization of this complex patient population. It is anticipated that continued education of caregivers and the treatment team will result in a greater effect. A multi-institutional implementation of this algorithm is needed to characterize risk factors associated with failure of outpatient management.

LEVEL OF EVIDENCE

III, Treatment Study.

Postoperative enterocolitis assessment using two different cut-off values in the HAEC score in Hirschsprung patients undergoing Duhamel and Soave pull-through

Background

Hirschsprung-associated enterocolitis (HAEC) is the most severe and potentially lethal complication of Hirschsprung disease (HSCR) which might occur following definitive surgery. Our objectives were: 1) to compare the incidence of HAEC after Duhamel and Soave procedures using different cut-off values of the HAEC scoring method; and 2) to associate them with the risk factors, including sex, aganglionosis type, mothers’ age at childbirth, gestational age, and mothers’ educational level.

Methods

Medical records of patients with HSCR who underwent Soave and Duhamel procedures in our institution, Indonesia (January 2012 – December 2016) were reviewed retrospectively. Two cut-off values of the HAEC scoring system (i.e., ≥10 and ≥ 4) were utilized.

Results

Eighty-three patients with HSCR were recruited in this study (Soave: 37 males and 7 females vs. Duhamel: 28 males and 11 females; p = 0.18). The incidence of HAEC after surgery was 14/83 (16.9%) and 38/83 (45.8%) for cut-off values of ≥10 and ≥ 4, respectively (p = 0.00012), and tended to have an association with sex (p = 0.09). Although it was not statistically significant (p = 0.07), the frequency of HAEC after Soave procedure tended to be higher in patients with their mother’s age of ≤35 years at childbirth than those with their mother’s age of > 35 years (OR = 7.9; 95% CI = 0.9–72.1). Multivariate analysis indicated none of the risk factors were associated with the frequency of HAEC after definitive surgery.

Conclusions

The lower cut-off value of ≥4 might increase the possibility to diagnose HAEC, particularly the mild cases. The incidence of HAEC after definitive surgery was not associated with any risk factors in our cohort patients. Further multicenter studies with a larger sample size are necessary to confirm our findings.

Hirschsprung-associated enterocolitis in children treated at US children's hospitals

BACKGROUND

The incidence of and risk factors for Hirschsprung's-associated enterocolitis (HAEC) following pull-through have been limited to single institutions studies. We characterized the incidence of, risk factors for, and consequences of post-operative HAEC.

METHODS

We identified children with Hirschsprung's Disease (HD) at US Children's Hospitals from 2007 to 2017 with and an associated pull-through operation at less than 1 year of age. HAEC readmissions were identified using ICD9/10 Diagnosis Codes and antibiotic administration. Hierarchical logistic regression models were developed for the risk factors for HAEC after pull-through and effects of recurrent HAEC on HD-related reoperations.

RESULTS

We identified 2030 children with HD, and 138 (7%) who had two or more readmissions related to HAEC. The frequency of recurrent HAEC by hospital ranged from 0 to 33%. Pre-operative HAEC, history of central nervous system infection, and congenital neurologic anomalies were associated with increased risk of recurrent HAEC. Recurrent HAEC was associated with HD-specific re-operation (OR 5.2, CI 3.3-8.1, p < 0.001); however, it was not associated with risk of in-hospital mortality (OR 3.3, CI 0.88-12.1, p = 0.08).

CONCLUSIONS

HAEC following pull-through occurs in a large proportion of infants with HD and predicts reoperation. Multicenter studies are needed to develop prediction models and treatment protocols for HAEC.

LEVEL OF EVIDENCE

II TYPE OF STUDY: Retrospective cohort study.

Risk factors of preoperative Hirschsprung-associated enterocolitis

Background

Hirschsprung-associated enterocolitis (HAEC) is a life-threatening complication of Hirschsprung disease (HSCR), that might occur preoperatively. We investigated the risk factors of preoperative HAEC.

Method

We retrospectively reviewed all medical records of HSCR patients admitted at Dr. Sardjito Hospital, Indonesia from March 2012 until March 2015. Diagnosis of HAEC was determined using the Delphi scoring system.

Results

Sixty-one HSCR patients were involved in this study, of whom 48 were males and 13 females. Eighteen percent (11/61) patients had a preoperative HAEC. The most common findings of the HAEC score found in our patients were distended abdomen (100%) and dilated loops of bowel (100%), followed by lethargy (72.7%), cut-off sign in rectosigmoid with absence of distal air (72.7%), leukocytosis (72.7%), and shift to left (63.6%). There was no association between gender, age of HSCR diagnosis, early/late diagnosis during neonatal period, aganglionosis type, albumin level nor body mass index with preoperative HAEC (p = 0.69, 0.76, 0.33, 1.0, 0.86, and 0.50, respectively). In addition, the maternal age, gestational age, and maternal education level also did not correlate with the development of preoperative HAEC (p = 0.71, 0.59, and 0.32, respectively).

Conclusion

The incidence of preoperative HAEC in our hospital is considered relatively moderate, with the most common findings of distended abdomen and dilated loops of bowel. None of the identified risk factors have an association with the development of HAEC in our patients.

Down Syndrome and Postoperative Complications in Children Undergoing Intestinal Operations

OBJECTIVE

This paper intends to evaluate the association between Down Syndrome (DS) and postoperative medical and surgical complications and inpatient postoperative mortality in pediatric patients undergoing intestinal operations.

METHODS

The 2012 Kids' Inpatient Database was queried to compare short-term postoperative medical and surgical complications and in-patient mortality among patients with DS undergoing intestinal operations to a cohort without DS using inverse probability weighting. Subset analysis was performed for patients undergoing intestinal operations exclusive of gastrostomy placement. Adverse treatment effects were calculated for the outcomes of interest.

RESULTS

Of 17,026 pediatric patients undergoing intestinal operations, 444 had DS. In unadjusted analysis, medical complications (urinary tract infection, deep venous thrombosis, sepsis, pneumonia) occurred in 7.9% of patients with DS, compared to 14.1% of those without (p < 0.001). Surgical complications (wound disruption, hemorrhage, superficial or deep wound infection) occurred in 3.5% of patients with DS, compared to 4.6% of those without (p = 0.34), and in-patient mortality occurred in 0.3% of patients with DS, compared to 2.7% of those without (p = 0.009). Adverse treatment effects (ATE) calculated after inverse probability weighting demonstrated no difference for medical or surgical complications but a significantly decreased mortality with DS.

CONCLUSIONS

Contrary to common perception and data extrapolated from the adult literature, pediatric patients with DS have neither higher medical nor surgical complication rates after intestinal operations. Similar to patients undergoing congenital heart surgery, pediatric patients with DS have a lower postoperative inpatient mortality after these general operations compared to those without DS. Mechanisms influencing risks in DS patient remain unknown.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Factors influencing the incidence of Hirschsprung associated enterocolitis (HAEC)

PURPOSE

This study aims to characterize risk factors for Hirschsprung-associated enterocolitis (HAEC). We hypothesize that earlier pull-through surgery is associated with lower risks of developing postoperative HAEC.

METHODS

A comparative study of 171 Hirschsprung patients treated from 1990 to 2017 was performed. Patients without HAEC were compared to patients with preoperative and/or postoperative HAEC. Results are presented as median [IQR] or frequency (%). Pearson's χ² test and Wilcoxon rank sum test were performed with a significance level at p < 0.05. Multivariable logistic regression analysis was used to adjust for potential confounders. A subanalysis was done to evaluate laparoscopic, laparotomy, and transanal surgeries.

RESULTS

Risk of developing preoperative HAEC was significantly associated with congenital malformations (OR 2.63 [1.11, 6.24]; p = 0.02). Birth weight was lower in patients with preoperative HAEC (OR 0.48 [95% CI 0.25, 0.93]; p = 0.03). On regression analysis, intestinal obstruction after surgery was significantly associated with postoperative HAEC (OR 8.2 [3.18, 21.13]; p < 0.0001). Patients with earlier pull-through surgery did not have a lower risk of developing postoperative HAEC.

CONCLUSIONS

Timing of surgery does not seem to be associated with a higher risk of developing pre- and postoperative HAEC. Predisposing factors for preoperative HAEC included associated malformations and lower birth weight, whereas intestinal obstruction was found to be associated with postoperative HAEC.

TYPE OF STUDY

Treatment study.

LEVEL OF EVIDENCE

Level III.

Risk factors for the development of post-operative enterocolitis in short segment Hirschsprung's disease

AIM OF THE STUDY

The objective of this study is to identify risk factors associated with the development of post-operative enterocolitis (HAEC), in short segment Hirschsprung's disease (HSCR-S).

METHODS

A retrospective study was carried out for post-operative patients with HSCR-S from 1997 to 2017. HSCR-S was defined as the most proximal extension of aganglionosis limited to the sigmoid colon. An episode of HAEC was defined as the presence of (1) vomiting or explosive diarrhea; (2) abdominal distension; (3) fever and (4) leukocytosis. Risk factors for the development of HACE were determined using multivariate logistic regression.

MAIN RESULTS

The medical records of 96 patients were reviewed. The overall incidence of HAEC was 20.8% (n = 20) and 65.0% (n = 13) of HAEC occurred within the first year of operation. After a univariate logistic regression analysis, three risk factors for HAEC were identified: (1) presence of other major anomalies [OR: 1.43 (1.12-2.32), p = 0.041]; (2) creation of pre-operative defunctioning stoma [OR: 2.28 (1.47-3.23), p = 0.035]; (3) extension of aganglionosis to the sigmoid colon [OR: 1.89 (1.05-3.19), p = 0.049]. After multivariate logistic regression analysis, a significant association was demonstrated for creation of pre-operative defunctioning stoma [OR: 1.81 (1.08-3.22), p = 0.045] and extension of aganglionosis to the sigmoid colon [OR: 1.91 (1.37-2.98), p = 0.038].

CONCLUSIONS

The requirement of pre-operative defunctioning stoma and a more proximal extension of aganglionosis are risk factors for the development of post-operative HAEC in HSCR-S. Patients with these risk factors should be closely followed up especially during the first year after the operation.

Advances in understanding the association between Down syndrome and Hirschsprung disease (DS-HSCR)

The clinical association between Trisomy 21 (Down syndrome) and aganglionosis (Hirschsprung disease; DS-HSCR) is well-established, being of the order of 5% and remains the most common congenital association with Hirschsprung disease. However, little consensus exists as to the possible etiologic and genetic factors influencing this association. Recent research has identified a number of levels at which development of the enteric nervous system is potentially affected in Trisomy 21. These include a decreased central pool of available neuroblasts for migration into the enteric nervous system, abnormal neuroblast type, poor synaptic nerve function and early germline gene-related influences on the migrating neuroblasts due to genetic mutations of a number of important developmental genes, and possible somatic mutations resulting from alterations in the local tissue microenvironment. In this paper, we review available evidence for this association. In addition, we provide evidence of both germline and somatic gene mutations suggesting causation. Although the picture is complex, recent associations between specific RET proto-oncogene variations have been shown to be significant in Down syndrome patients with Hirschsprung disease, as they probably interfere with vital RET functions in the development of the autonomic and enteric nervous systems, increasing the risk of disturbed normal function. In addition, we explore potential role of other facilitatory influence of other susceptibility genes as well as potential other chromosome 21 gene actions and the microenvironment on the Down syndrome gastro-intestinal tract. The various ways in which trisomy of chromosome influences the enteric nervous system are becoming clearer. The sum of these effects influences the outcome of surgery in Down syndrome patients with Hirschsprung Disease.

Increased Risk of Inflammatory Bowel Disease in a Population-based Cohort Study of Patients With Hirschsprung Disease

OBJECTIVES

Hirschsprung disease (HSCR) has previously been associated with inflammatory bowel disease (IBD). There are no data to show how common this association is. The aim of the present study was to assess the risk of IBD in individuals with HSCR in a population-based cohort.

METHODS

This was a nationwide, population-based cohort study. The study exposure was HSCR and the study outcome was IBD. The cohort included all individuals with HSCR registered in the Swedish National Patient Register between 1964 and 2013 and 10 age- and sex-matched controls per patient, randomly selected from the Swedish Population Register. Individuals with IBD were identified in the Swedish National Patient Register. Data were validated by checking for relevant surgical procedures, and, or prescription of drugs for IBD registered in the Swedish Drug Registry.

RESULTS

The cohort comprised 739 individuals with HSCR (565 boys) and 7390 controls (5650 boys). The median age at diagnosis of IBD was not different between the groups; 19 years (5-34) versus 21 years (7-37), P = 0.21. Twenty of the 739 individuals with HSCR and 41 of the 7390 controls had IBD, odds ratio 4.99, and 95% confidence interval 2.85 to 8.45. In the exposed group, 15 individuals had Crohn disease and 5 ulcerative colitis at their latest admission compared to 18 individuals with Crohn disease and 23 with ulcerative colitis in the unexposed group, P = 0.030.

CONCLUSION

There is an increased risk of IBD in patients with HSCR, which should be considered in clinical practice.

Pathologically assessed grade of Hirschsprung-associated enterocolitis in resected colon in children with Hirschsprung's disease predicts postoperative bowel function

PURPOSE

The aim of this study was to investigate the relationship between the grade of enterocolitis on pathological assessment of resected colon and postoperative bowel function in children with Hirschsprung's disease (HD).

METHODS

Children with HD who were seen at a large tertiary center from January 2012 to December 2013 were enrolled into this study. Resected colon was assessed using the histopathologic grade scoring system for Hirschsprung-associated enterocolitis (HAEC), and the relationship of these scores to postoperative bowel function was assessed. Time of recovery to normal defecation was the primary outcome measure. The t-test, analysis of variance, and Kaplan-Meier, univariate, and multiple regression analyses were performed.

RESULTS

Eighty children with HD (median age at repair 7.9months; range 1.3months to 9years) were included in the study. Nineteen children dropped out of the study and were considered as providing censored data, giving a follow-up rate of 76.3%. A total of 21 children (34.4%) were admitted to hospital with at least one episode of enterocolitis. Multivariate Cox proportional hazards models showed that compared with patients with a normal proximal colon, those with an inflamed proximal segment had a 1.5-fold higher risk of a poor recovery. Logistic regression analyses suggested that postoperative HAEC admissions increased by 57% with each HAEC pathological grade of the transitional segment and by 50% with each grade of the overall segment. Compared with normal bowel in the transitional segment, the detection of grade ≥3 HAEC in the transitional area increased the incidence of postoperative HAEC by 4.75-fold.

CONCLUSIONS

Children whose resected proximal colon showed inflammation on pathological assessment were at risk of poor recovery after surgery. A higher pathological HAEC score for the sum of the overall three segments suggested an increased risk for the subsequent development of enterocolitis. Among three segments, the severity of enterocolitis in the transitional segment was the most significant factor in predicting postoperative HAEC.

TYPE OF STUDY

Clinical study.

LEVEL OF EVIDENCE

Moderate.

Functional outcomes in Hirschsprung disease: A single institution's 12-year experience

AIMS

Hirschsprung disease (HD) is a chronic condition associated with long-term morbidity. We assessed the short and long-term functional outcomes of operated patients in a single institution over a 12-year period.

MATERIALS AND METHODS

We conducted a retrospective review of all children operated for HD between 2002 and 2014. Postoperative functional outcomes were assessed using the Rintala Bowel Function Score (BFS, 0-20, 20=best score). We assessed hospital admissions, complications including Hirschsprung associated enterocolitis (HAEC) and the need for further surgical procedures.

RESULTS

72 (52 male) patients were studied, of whom, 6 (8%) had a positive family history, 5 (7%) had Trisomy 21 and 5 (7%) had total colonic HD. The median age at diagnosis was 6.5days (2 days-6.7 years) and median follow-up was 6years (1-12years). All patients except two underwent a Duhamel pull-through procedure. The median age at surgery was 4months (6days-90months). 37 (51%) procedures were performed single-stage and 7 (10%) were laparoscopically assisted. Our early complication rate was 15%; 11 (15%) patients were treated for HAEC and 43 (60%) did not require any further surgery. 12 (17%) underwent injection of botulinum toxin, 7 (10%) needed residual spur division and 4 (5%) required an unplanned, post pull-through enterostomy for obstructive defecation symptoms and HAEC. Two (3%) patients underwent an Antegrade Colonic Enema (ACE) stoma. The median BFS was 17 (5-20). There were two deaths both out of hospital.

CONCLUSIONS

Long-term functional outcomes following Duhamel Pull-Through surgery are satisfactory although 40% of patients needed some form of further surgical intervention. The management of anal sphincter achalasia has improved with the use of botulinum toxin and we advocate aggressive and early management of this condition for symptoms of obstructive defecation and HAEC.

LEVEL OF EVIDENCE

III.

Enterocolitis and bowel function in children with Hirschsprung disease and trisomy 21

BACKGROUND/PURPOSE

The purpose of this study was to study the effect of trisomy 21 (T21) on enterocolitis rates and bowel function among children with Hirschsprung disease (HD).

METHODS

A retrospective cohort study of patients with HD treated at our tertiary children's hospital (2000-2015) and a cohort of patients with HD treated in our pediatric colorectal center (CRC) (2011-2015) were performed.

RESULTS

26/207 (13%) patients with HD had T21. 70 (41%) with HD alone were diagnosed with enterocolitis episodes compared to 9 (38%) with HD+T21 (p=0.71). 55/207 patients were managed in the CRC. 11/55 patients (20%) had HD+T21. 25 (58%) with HD had one or more enterocolitis episodes compared to 4 (36%) with HD+T21 (p=0.20). Number of hospitalizations for enterocolitis was similar between all groups. Toilet training was assessed in 32 CRC patients (25 HD, 7 HD+T21). One child with HD+T21 was toilet trained by age 4years versus 12 with HD (p=0.20). Laxative or enema therapy was required for constipation management in 57% HD versus 64% HD+T21.

CONCLUSION

Enterocolitis rates in children with HD+T21 did not differ from rates in children with HD alone. The majority of patients with CRC follow-up had constipation requiring laxative or enema therapy, which demonstrates the need for consistent postoperative follow-up.

LEVEL OF EVIDENCE

Retrospective Study - Level II.

Infant's Age Influences the Accuracy of Rectal Suction Biopsies for Diagnosing of Hirschsprung's Disease

BACKGROUND & AIMS

Hirschsprung's disease (HD) is a rare birth defect of the distal colon. Analysis of rectal suction biopsy (RSB) is considered to be the most reliable method for its diagnosis in infants. However, the diagnostic accuracy of RSB analysis could be affected by the patient's age, possibly because of rapid development of the enteric nervous system in the first weeks after birth. Because there is a trend toward testing for HD at early ages, we aimed to determine whether the diagnostic accuracy of RSB analysis is associated with the patient's age.

METHODS

We performed a retrospective analysis of all patients from whom 1 or more RSBs were analyzed from 1975 through 2011 (529 RSBs from 441 patients). Outcomes of RSB analyses were categorized as positive, inconclusive, or negative for HD. Primary diagnoses, based only on RSB, were compared with final diagnoses made after at least 1 year of clinical follow-up. Age at time of RSB analysis was corrected for the gestational age. By using these criteria, we determined the diagnostic accuracy of RSB analysis for different age groups.

RESULTS

RSB analysis identified HD in patients with sensitivity values of 46% (patients -45 to 7 days old), 47% (8-22 days old), and 62% (23-39 days old) (corrected for gestational age). The average sensitivity with which RSB analysis identified HD in patients older than 39 days was 88%. RSB identified HD in patients younger than 39 days old with significantly lower sensitivity than in older patients (50% vs 88%, P < .001). The specificity with which RSB identified infants without HD was not affected by age (average 95%). Of all RSBs, 11% were inconclusive for the diagnosis of HD.

CONCLUSIONS

RSB analysis identifies HD in patients younger than 39 days old with only 50% sensitivity. Moreover, RSBs obtained from younger patients often lead to inconclusive outcomes and require additional biopsies. We propose that for infants suspected of HD at these ages, a noninvasive technique, such as anorectal manometry, should be used for a primary diagnosis. RSB should thereafter be used to confirm the diagnosis when the infant is older than 39 days.

Effects of lipopolysaccharide-induced inflammation on the interstitial cells of Cajal

Interstitial cells of Cajal (ICC) have recently been found to display phenotypic changes. The present study is designed to determine whether phenotypic changes occur in ICC associated with an inflammatory microenvironment and whether the ICC phenotype could be recovered after the discontinuation of inflammatory stimuli. Immunohistochemistry studies revealed that the functional ICC marker, c-kit, was markedly reduced in patients with Hirschsprung's disease (n = 34) compared with controls (n = 12), whereas another marker of ICC, CD34, was not altered significantly. Compared with the vehicle group (n = 6), intraperitoneal injection of lipopolysaccharide (LPS; 1.5 mg/kg) in mice (n = 6) significantly induced plasma tumor necrosis factor-alpha (TNF-α) levels as determined by enzyme-linked immunosorbent assay. Western blot and real-time polymerase chain reaction assessment further showed that LPS injection markedly suppressed intestinal c-kit protein and mRNA expression, which could be blocked by Toll-like receptor 4 (TLR4) deficiency (n = 6) rather than TLR2 deficiency (n = 6) and had no effects on CD34. Compared with the vehicle group (n = 6), intraperitoneal TNF-α (30 μg/kg) administration (n = 6) also significantly reduced intestinal c-kit protein and mRNA levels but not CD34 levels. However, the reduction of c-kit induced by TNF-α injection was not suppressed by TLR4 deficiency (n = 6). Intestinal c-kit protein and mRNA levels were markedly restored after the discontinuation of TNF-α administration for 7 days. Moreover, immunofluorescence analysis of primary ICC further confirmed that exposure to TNF-α for 24 h suppressed c-kit expression, which could be restored after discontinuation of TNF-α exposure. CD34 expression was not altered upon exposure to TNF-α. Thus, phenotypic changes in ICC occur in an inflammatory microenvironment in the gut and LPS, TLR4 and TNFα are crucial to this process.

Impact of cow's milk allergy on enterocolitis associated with Hirschsprung's disease

PURPOSE

To investigate the impact of cow's milk allergy (CMA) on infants with Hirschsprung's disease (HD).

METHODS

Twenty-four patients, who developed gastrointestinal symptoms before the age of 60 days and underwent surgery for HD in the period between January 2003 and December 2012, were enrolled in this study. They were divided into two groups based on CMA-related findings: stimulation index of lymphocyte stimulation test >300 % and the presence of eosinophilic infiltration in the resected colon. Ten patients were determined specimen as not having CMA (Group A), because they did not satisfy any of the criteria. The remaining 14 were determined as having possible CMA (Group B), because they satisfied either or both findings. Patient background characteristics, pre- and postoperative clinical history, and laboratory data were compared between Groups A and B.

RESULTS

Pre- and postoperative enterocolitis did not occur in Group A patients. Postoperative enterocolitis was more frequent in Group B than in Group A (p = 0.04). Other clinical and laboratory data did not show significant difference between the two groups.

CONCLUSION

CMA is a possible risk factor for postoperative enterocolitis in patients with HD.

Hirschsprung's disease associated with Down syndrome: a meta-analysis of incidence, functional outcomes and mortality

PURPOSE

Down syndrome (DS) is the most frequent chromosomal abnormality associated with Hirschsprung's disease (HD). It has often been suggested that this association results in poorer outcomes with regard to postoperative complications, continence and mortality. On the other hand, the results after surgical treatment of HD in patients with DS are reportedly similar to those in cases with HD alone. The objective of this study was to determine the incidence of DS in cohorts with HD, and to compare pre-/postoperative complications, functional outcome and mortality between cohorts with and without coexisting DS.

METHODS

A systematic literature-based search for relevant cohorts was conducted using multiple online databases. The number of DS cases in HD cohorts was recorded and data on pre-/postoperative complications, functional outcome and mortality were extracted. Pooled odds ratios with 95% confidence intervals were calculated using meta-analysis methodology.

RESULTS

Sixty-one articles met defined inclusion criteria, comprising data from 16,497 patients with HD. The overall incidence of DS among them was 7.32%. Vice versa, the incidence of HD in 29,418 patients with DS was 2.62%. There were no significant differences regarding the male-to-female ratio between cohorts with and without coexisting DS (4:1 vs. 3:1 respectively; P = 0.5376). The rate of additional comorbidities was significantly higher in HD associated with DS (P < 0.0001). Recto-sigmoid HD was in both cohorts the most common type of HD (P = 0.8231). Long-segment HD was significantly more frequent in HD with coexisting DS (P = 0.0267), while total colonic aganglionosis occurred significantly more often in HD without DS (P = 0.0003). There were no significant differences in preoperative constipation/obstruction (P = 0.5967), but the rate of preoperative enterocolitis was significantly higher in HD associated with DS (P = 0.0486). Postoperative complications such as recurrent enterocolitis (P = 0.0112) and soiling (P = 0.0002) were significantly more frequent in HD with coexisting DS. Although not statistically significant, fecal incontinence (P = 0.1014) and persistent constipation (P = 0.1670) occurred more often after surgical treatment of HD with DS. The mortality rate was significantly higher in HD associated with DS (P < 0.0001).

CONCLUSIONS

The association of HD with DS is well-recognized with an incidence of 7.32%. A large number of patients with DS continue to have persistent bowel dysfunction after surgical treatment of HD. Our data provide strong evidence that the coexistence of HD and DS is associated with higher rates of pre-/postoperative enterocolitis, poorer functional outcomes and increased mortality.

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.

Sudden unexpected early neonatal death due to undiagnosed Hirschsprung disease enterocolitis: a report of two cases and literature review

Hirschsprung enterocolitis (HEC) is an uncommon, albeit well known, complication of Hirschsprung disease (HD). It is multifactorial and can appear in different age groups, but is particularly important in the neonatal period where it is characteristically seen in full-term neonates. Two cases of HEC are reported that were diagnosed at post-mortem examination, which presented as early sudden neonatal death, with a review the literature on fatal Hirschsprung enterocolitis. Case 1 was a 4-day old male neonate who was found unwell, struggling to breath, and with green vomitus. He was taken to hospital and pronounced dead a short time later. According to the parents meconium was passed on the first day. Post-mortem examination demonstrated necrotizing enterocolitis with isolated bowel perforation. Histology disclosed unsuspected HD. Case 2 was a 2-day old male neonate who was found wheezing with green vomitus. He arrived floppy, cyanosed, and in shock at the hospital and died a few hours later. Meconium was not passed, according to the parents. Post-mortem examination revealed necrotizing enterocolitis. There was also recto-sigmoidal aganglionosis and acetylcholinesterase staining confirmed HD. HEC is a multifactorial and sometimes recurrent complication of HD which characteristically develops in full-term neonates. Presentation with early sudden neonatal death is rare but should be considered in the diagnostic work-up of sudden deaths in this age group.

Probiotic prophylaxis after pullthrough for Hirschsprung disease to reduce incidence of enterocolitis: a prospective, randomized, double-blind, placebo-controlled, multicenter trial

OBJECTIVE

Hirschsprung-associated enterocolitis (HAEC) is one of the most troublesome problems encountered after a pullthrough. We hypothesized that prophylactic administration of probiotics after a pullthrough procedure would decrease the incidence of HAEC.

STUDY DESIGN

A prospective, double-blind, placebo-controlled, randomized trial was conducted at 2 children's hospitals. Infants undergoing pullthrough were randomized to probiotic or placebo for a period of 3 months post-pullthrough. Primary outcome was incidence of post-operative HAEC. Other outcomes included severity of HAEC by clinical grade, number of HAEC episodes and extent of aganglionosis. Pearson Chi Square analysis, as well as logistic regression, was used for statistical analysis.

RESULTS

Sixty-two patients were recruited (Sites: A=40; B=22). One was lost to follow up and one immediate post-op death was not included in final analysis. Probiotics were administered to 32 patients. Distribution of placebo/probiotics was equal between sites (P=0.858). Mean age at pullthrough was 6.5 ± 8.1(± SD) months. The incidence of HAEC was 28.3%. The incidence of HAEC was not statistically different between probiotic and placebo study groups.

CONCLUSIONS

Incidence of HAEC was not reduced with prophylactic probiotics. Future studies are needed to better determine the etiology and possible ways of preventing this complex condition.

The pathogenesis of Hirschsprung's disease-associated enterocolitis

Hirschsprung's disease-associated enterocolitis (HAEC) remains the most life-threatening complication in Hirschsprung disease (HD) patients. The pathogenesis of HAEC has not been determined and many hypotheses regarding the etiology of HAEC have been proposed. These include a possible causal relationship between the abnormal enteric nervous system development in HD and the development of enterocolitis. Based on the complex genetic causes of HD that have been discovered and the resultant heterogeneous group of patients that exists, the causes of HAEC are likely multiple. New insights regarding the relationship of the role of the enteric nervous system and its interaction between intestinal barrier function, innate host immunity, and commensal microflora have been discovered, which may shed light on this perplexing problem. This review presents current known risk factors of HAEC and the proposed theories and supporting evidence for the potential etiologies of HAEC.

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.

[Enterocolitis as a complication of late-diagnosed Hirschsprung disease]

Enterocolitis is the most serious complication of Hirschsprung disease. Early management of these patients can decrease the severity of this complication. Hirschsprung disease is more common in patients with trisomy 21 than in the general population. Furthermore, the risk of developing enterocolitis is higher in this population. We report on an infant with trisomy 21 who developed enterocolitis as a complication of Hirschsprung disease that was diagnosed late when the infant presented with septic shock leading to death of the patient.

Clinical impacts of delayed diagnosis of Hirschsprung's disease in newborn infants

BACKGROUND

Asian infants are at a higher risk of having Hirschsprung's disease (HD). Although HD is surgically correctable, serious and even lethal complications such as Hirschsprung's-associated enterocolitis (HAEC) can still occur. The aim of this study was to investigate the risk factors of HAEC, and the clinical impacts of delayed diagnosis of HD in newborn infants.

PATIENTS AND METHODS

By review of medical charts in a medical center in Taiwan, 51 cases of neonates with HD between 2002 and 2009 were collected. Patients were divided into two groups based on the time of initial diagnosis: Group I, diagnosis made within 1 week after birth, and Group II after 1 week. Clinical features including demographic distribution, presenting features of HD, short-term and long-term complications related to HD were compared between the two groups of patients.

RESULTS

There were 25 patients in Group I and 19 in Group II. Group II patients had more severe clinical signs and symptoms of HAEC than Group I patients. The incidence of preoperative HAEC was 12% in Group I and 63% in Group II (adjusted odds ratio = 12.81, confidence interval = 2.60-62.97). Patients with preoperative HAEC were more likely to develop adhesive bowel obstruction after operation (33% vs. 3%, p = 0.013) and failure to thrive (33% vs. 3%, p = 0.013). Also, patients with long-segment or total colonic aganglionosis were at risk of developing both postoperative HAEC (85% vs. 29%, p = 0.001) and failure to thrive (39% vs. 3%, p = 0.002).

CONCLUSION

In our study, we found that delayed diagnosis of HD beyond 1 week after birth significantly increases the risk of serious complications in neonatal patients. Patients with long-segment or total colonic aganglionosis have higher risk of postoperative HAEC and failure to thrive. Patients with preoperative HAEC are more likely to have adhesive bowel obstruction and failure to thrive.

Is daily dilatation by parents necessary after surgery for Hirschsprung disease and anorectal malformations?

BACKGROUND/PURPOSE

Most surgeons recommend daily dilatation after surgery for Hirschsprung disease and anorectal malformations. Our goal was to critically evaluate the potential risks and benefits of this practice.

METHODS

A retrospective chart review was carried out of all children undergoing repair of Hirschsprung disease or anorectal malformation over 5 years. Patients with long segment Hirschsprung disease or anal stenosis were excluded.

RESULTS

There were 95 patients, of which 34 had Hirschsprung disease and 61 had an anorectal malformation. Postoperatively, 65 underwent routine dilatation by parents; and 30 underwent weekly calibration by the surgeon, with daily dilatation by the parents only if the anastomosis was felt to be narrow. Of the 30 children undergoing weekly calibration, only 5 (17%) developed late narrowing that required conversion to the daily parental dilatation approach. There were no significant differences between the 2 approaches with respect to stricture development, anastomotic disruption, perineal excoriation, or enterocolitis.

CONCLUSION

Weekly calibration by the surgeon is associated with similar outcomes to daily dilatation by the parents. Because this approach is kinder to the parents and the child, it should be seriously considered for the postoperative management of children with Hirschsprung disease or anorectal malformations.

Hirschsprung's disease and the brain

A link between factors governing brain development and the development of the ENS is not surprising as both processes are largely controlled by the same or similar neural growth factors which are expressed at more or less in the same spatio-temporal time frame. Hirschsprung's disease (HSCR) occurs as an isolated phenotype in 70% of cases but is associated with other congenital abnormalities and syndromic phenotypes in the remainder, with CNS anomalies making up 6.78%. These associations may be underestimated and are possibly pathogenetically linked to genetic associations and probable gene-gene interaction. In this review we explore known syndromes and other ENS associations of HSCR, looking at possible pathogenetic associations. We point out that borderline cognitive abilities, attention-deficit disorders and possible epileptic seizures in Hirschsprung's patients should be fully investigated. We recognise that this group of patients remain a challenge from a clinical and functional management point of view, and suggest possible management guidelines.

Hirschsprung's disease in the neurologically challenged child

BACKGROUND

The association between Hirschsprung's disease (HSCR) and central nervous system (CNS) anomalies and syndromes is interesting because of similar developmental pathways. In addition to associated syndromes (e.g., Trisomy 21), these include brain anomalies, mental retardation and growth, ear and hearing deformities, eye hypoplasia, and craniofacial abnormalities, suggesting an neurocristopathy. This group of patients present with neurological challenges and have special challenges in management especially in the older child and adolescent.

METHODS

We retrospectively investigated 32 patients with significant HSCR-associated neurological challenges out of a local database of 555 HSCRs (6%). Data were analyzed with details of neurological problem, treatment, complications, and mortality. Long-term outcome was assessed clinically.

RESULTS

A total of 32 neurologically challenged children were studied. The male/female ratio was 1.7:1 and all ethnic groups were affected. Abnormalities and syndromes included Down (n = 16) and probable Mowat-Wilson (n = 2) syndromes. Other abnormalities included ophthalmic problems (n = 8), CNS and brain abnormalities (n = 8). Mortality (22%) was mostly related to enterocolitis, particularly in Trisomy 21, ophthalmic problems (n = 8), CNS and brain abnormalities (n = 8). Follow-up age range was 1-34 years (8 years, adolescence and beyond). The outcome was variable, concomitant medical problems were common. Several patients failed to achieve satisfactory continence.

CONCLUSION

The association of neurological difficulties in patients with HSCR presents many challenges. Management could involve the exploration and evaluation of alternative treatment choices.

Systematic review and meta-analysis of enterocolitis after one-stage transanal pull-through procedure for Hirschsprung's disease

PURPOSE

The transanal one-stage pull-through procedure (TERPT) has gained worldwide popularity over open and laparoscopic-assisted one-stage techniques in children with Hirschsprung's disease (HD). It offers the advantages of avoiding laparotomy, laparoscopy, scars, abdominal contamination, and adhesions. However, enterocolitis associated with Hirschsprung's disease (HAEC) still remains to be a potentially life-threatening complication after pull-through operation. The reported incidence of HAEC ranges from 4.6 to 54%. This meta-analysis was designed to evaluate postoperative incidence of HAEC following TERPT procedure.

METHODS

A meta-analysis of cases of TERPT reported between 1998 and 2009 was performed. Detailed information was recorded regarding intraoperative details and postoperative complications with particular emphasis on incidence of HAEC. Diagnosis of HAEC in a HD patient was based on the clinical presentation of diarrhoea, abdominal distension, and fever.

RESULTS

Of the 54 published articles worldwide, 27 articles, including 899 patients were identified as reporting entirely TERPT procedure. Postoperative HAEC occurred in 92 patients (10.2%). Recurrent episodes of HAEC were reported in 18 patients (2%). Conservative treatment of HAEC was successful in 75 patients (81.5%), whereas in 17 patients (18.5%) surgical treatment was needed.

CONCLUSIONS

This systematic review reveals that TERPT is a safe and less-invasive procedure with a low incidence of postoperative HAEC.

Murine model of Hirschsprung-associated enterocolitis. I: phenotypic characterization with development of a histopathologic grading system

PURPOSE

The aim of the study was to characterize enterocolitis in the Ednrb-null (Ednrb-/-) mouse with aganglionosis of the colon and to develop and validate a semiquantitative histopathologic grading system to assess enterocolitis.

METHODS

We isolated colon and ileal specimens of Ednrb-/- and control mice (Ednrb+/+) and performed histochemical staining (H&E) on tissue sections. After establishing inflammation grading criteria, 2 blinded pathologists independently assessed the severity and depth of inflammation of proximal colon segments on 2 separate occasions. Interclass correlations (ICCs) and coefficient of variation (CV) were calculated to determine interrater and intrarater agreement. We then prospectively applied the enterocolitis grading system to Ednrb-/- mice that became clinically ill. A cohort of Ednrb-/- mice were observed until they developed clinical illness, at which time they were euthanized and had multiple organ homogenates cultured for bacteria, and colon and small bowel were histopathologically graded for enterocolitis. Spearman's rank correlations comparing enterocolitis scores with level of bacteremia were performed.

RESULTS

Intra- and interrater ICCs of the histologic scoring system were satisfactory (0.61 and 0.94, respectively), as were intra- and interrater CVs (18% and 9%, respectively). Of the Ednrb-/- mice, 65% developed bacteremia. Those with bacteremia had significantly higher enterocolitis scores than those without bacteremia (P < .01). Ednrb-/- mice that developed bacteremia showed a strong positive correlation between total enterocolitis scores and number of bacterial colony forming units in peritoneal lavage, liver, kidney, and aerobic spleen.

CONCLUSIONS

The Ednrb-/- mouse with aganglionosis develops enterocolitis and has features similar to Hirschsprung-associated enterocolitis in humans. Our grading system is a reliable way to assess enterocolitis. By performing microsurgical pull-through, we can now perform controlled, hypothesis-driven, mechanistic studies to evaluate etiologic factors affecting enterocolitis in the Ednrb-/- mouse.

Practical pathology and genetics of Hirschsprung's disease

Diagnosis and management of Hirschsprung's disease (HSCR) requires understanding of the malformation's anatomic features and multigenic nature. Rectal biopsies, intraoperative frozen sections, and resection specimens provide invaluable information. Extraction of these data requires thoughtful biopsy technique, adequate histologic sections, histochemistry, and collaboration of surgeon and pathologist. Critical consideration of transition zone anatomy and published studies of "transition zone pull through" indicate that more research is needed to determine how much ganglionic bowel should be resected from HSCR patients. Many HSCR-susceptibility genes have been identified, but mutational analysis has limited practical value unless family history or clinical findings suggest syndromic HSCR.

Low incidence of enterocolitis and colonic mucosal inflammation in Norwegian patients with Hirschsprung's disease

BACKGROUND

Hirschsprung's disease (HD) may be associated with inflammation in the colon. Further, the etiology of Hirschsprung-associated enterocolitis (HEC) is unclear. To learn more about these features, we examined our cohort of HD patients during a period of 6 years for inflammation in their colonic mucosa as well as for signs of HEC.

MATERIALS AND METHODS

Rectal suction biopsies and operative full thickness aganglionic and ganglionic colonic specimens from 36 patients were examined. Signs of inflammation were recorded in hematoxylin/eosin/saffron (HES)-stained sections and with fluorescence conjugated polyclonal antibodies to IgA and IgG applied on serial sections. The suction biopsies were also evaluated for the presence of mucus inspissation and crypt dilatation. Clinical signs of HEC were recorded from medical files of the same 36 patients.

RESULTS

HES-staining revealed that seven patients had inflammation in the suction biopsies; these patients were significantly older than the patients without inflammation. Slight mucus inspissation was identified in suction biopsies of five out of 33 patients, but crypt abscesses or ulcerations were not found in any specimens. Virtually all very young patients (<3 months) had slight crypt dilatation. We identified inflammation in resected colonic segments from 17 out of 36 patients. Thirteen of these 17 had a diverting colostomy, and only one out of 14 patients with colostomy had no inflammation. Inflammatory changes were similar in ganglionic and aganglionic bowel. By immunofluorescence (IF) staining, inflammation was found in resected colonic segments from five patients. Four of these had a colostomy. HEC was diagnosed in three patients, and inflammation detected in resected specimens from only one of these three.

CONCLUSIONS

We have not been able to identify particular characteristics in the colonic or rectal mucosa that are linked to development of HEC. Inflammation in the resected specimen was mainly found in patients with a diverting colostomy, and then in both ganglionic and aganglionic colon.

Development of a standardized definition for Hirschsprung's-associated enterocolitis: a Delphi analysis

PURPOSE

The reported incidence of Hirschsprung's-associated enterocolitis (HAEC) is extremely variable. A standardized definition would permit comparison of different studies and provide an interpretable outcome measure for future prospective studies in patients with Hirschsprung's disease.

METHODS

The Delphi method is a technique for achieving consensus among a panel of experts. A list of 38 potential criteria from the history, physical examination, radiologic studies, and pathologic specimens was made available to pediatric surgeons and gastroenterologists who have contributed to the literature on Hirschsprung's disease. Each expert ranked the diagnostic importance of each item using a Likert scale. In subsequent surveys, the same process was used, but the means and SDs from previous rounds were included as a way of influencing the experts toward consensus. Cronbach's alpha was used after each round to measure variability among the experts. Once consensus was reached, an overall "HAEC score" was developed by assigning a value of 1 or 2 to each item that was considered important by the expert panel. The score was then validated by circulating 10 clinical cases to the panel and asking if each represented HAEC or not.

RESULTS

Twenty-seven experts completed the survey. Cronbach's alpha increased from 0.93 after the first round to 0.97 after the second. Criteria receiving the highest scores were diarrhea, explosive stools, abdominal distension, and radiologic evidence of bowel obstruction or mucosal edema. Eighteen items were included in the score. During the validation process, the score agreed with the experts in 9 of the 10 case scenarios.

CONCLUSION

The most important clinical diagnostic criteria for HAEC were identified from a larger pool of potential diagnostic items through a consensus approach using the Delphi method. A score was developed and validated and can now be used as a standardized and reproducible outcome measure for future studies in children with Hirschsprung's disease.

Hirschsprung disease

Hirschsprung disease is a relatively common condition managed by pediatric surgeons. Significant advances have been made in understanding its etiologies in the last decade, especially with the explosion of molecular genetic techniques and early diagnosis. The surgical management has progressed from a two- or three-stage procedure to a primary operation. More recently, definitive surgery for Hirschsprung disease through minimally invasive techniques has gained popularity. In neonates, the advancement of treatment strategies for Hirschsprung disease continues with reduced patient morbidity and improved outcomes.

Down syndrome and the enteric nervous system

Down syndrome (DS) is the most common chromosomal abnormality occurring in humans. Up to 77% of DS children have associated gastrointestinal (GI) abnormalities, which may be structural or functional in nature. Functional disturbances may, in turn, affect the outcome of corrective surgical procedures, prompting to caution. It is becoming clear that the processes affecting the enteric nervous system (ENS) in DS not only affect the micro-anatomy but also nerve function, and there is some histological evidence of ENS variations in both human and DS animal models. This suggests that developmental disorders of the ENS are probably fundamental to the functional GI disturbances encountered in patients with DS. The anomalous brain development, function and resulting intellectual impairment associated with DS appears to result from the genetic imbalance created by the trisomy of chromosome 21. The possible links between the brain, GI and ENS involvement are not as yet entirely clear. Neurotropic factors affecting brain development during embryogenesis are probably interlinked with ENS development, but the precise mechanism of how this occurs has yet to be established. This study explores what is known about the ENS dysfunction in DS and reviews the possible importance of chromosome 21 located and other genes in its etiology. Functional motor disturbances of the esophagus and colon are not uncommon and may be congenital or acquired in nature. The most prominent of these include esophageal dysmotility syndromes (e.g. achalasia, gastroesophageal reflux, dysphagia) as well as a higher incidence of chronic constipation and Hirschsprung's disease (HSCR) (2-15%) occurring in association with DS. Chromosome 21 itself is thought to be the site of a modifier gene for HSCR. Recently identified candidate genetic mechanisms provide unique insights into the genetic background of the neurological and cognitive disorders associated with DS. Although the role of the triplicated chromosome 21 and genetic dosage remain important, the additional role of other chromosome 21 genes in the etiology of ENS developmental anomalies remains undetermined and requires ongoing research.

The ITGB2 immunomodulatory gene (CD18), enterocolitis, and Hirschsprung's disease

Hirschsprung's disease (HSCR)-associated enterocolitis (HAEC) remains a major contributor to morbidity and mortality associated with HSCR, being sometimes difficult to diagnose in its subclinical form. Its pathogenesis appears to include impaired local defense mechanisms as well as dysfunctional immune response and leukocyte function. In this context, the ITGB2 (CD18) immunomodulation-related gene is a possible candidate in HAEC pathogenesis as it codes for the beta-subunit of leukocyte adhesion molecule lymphocyte function-associated antigen 1, which has an established role in T-cell development and function. ITGB2/CD18 has also been linked to chronic colitis in both human and animal models involving defense mechanisms within colonic mucosa. There is therefore a fairly compelling case for the potential involvement of the ITGB2 (CD18) in HAEC pathogenesis.

AIM

The aim of this study was to investigate the ITGB2 immunomodulatory gene (CD18) in a cohort of patients with HSCR and explore its correlation with enterocolitis.

PATIENTS AND METHODS

Screening for mutations of the ITGB2 (CD18) gene was performed on DNA extracted from colonic tissue samples and whole blood of 33 HSCR patients controlled by analysis of 60 unaffected individuals from the diverse South African population. Polymerase chain reaction amplification was performed, followed by heteroduplex single-strand conformation polymorphism analysis and bidirectional semiautomated DNA sequencing analysis.

RESULTS

Heteroduplex single-strand conformation polymorphism banding patterns of the ITGB2 gene showed variations in 22 HSCR patients (66%), 13 of whom had severe episodes of HAEC, and 6 others had milder symptoms. Of the 13, 6 (46%) had Down's syndrome-associated HSCR. Genetic variations included 1 mutation (D77N), 2 known (V367, V441), and 4 novel polymorphisms (-111T/C, 24G/T, 295G/A, 892A/G). Significant associations were identified in the exon 5' untranslated promotor region (P < .0001), exon 10 (P < .0007), and the 3' untranslated promotor region at 122G/A (P < .0001) and 370 G/T positions (P = .04). Those regions of the gene most frequently associated with HAEC and severe symptoms were those with more than 1 variant identified in the gene.

CONCLUSIONS

This study shows that impaired CD18 leukocyte and T regulatory cell regulation can probably be linked to a genetic (ITGB2) predisposition to HAEC. It furthermore provides a possible genetic link to HAEC patient selection, identifying a potential molecular target.

Older age at diagnosis of Hirschsprung disease decreases risk of postoperative enterocolitis, but resection of additional ganglionated bowel does not

PURPOSE

This study was conducted to determine the effect of age at diagnosis and length of ganglionated bowel resected on postoperative Hirschsprung-associated enterocolitis (HAEC).

METHODS

Children who underwent endorectal pull-through (ERPT) between January 1993 and December 2004 were retrospectively reviewed. t Test, analysis of variance, Kaplan-Meier, and Cox's proportional hazards analyses were performed.

RESULTS

Fifty-two children with Hirschsprung disease (median age, 25 days; range, 2 days-16 years) were included. Nineteen (37%) had admissions for HAEC. Proportional hazards regression showed that HAEC admissions decreased by 30% with each doubling of age at diagnosis (P = .03) and increased 9-fold when postoperative stricture was present (P < .01), after controlling for type of ERPT, trisomy 21, transition zone level, and preoperative enterocolitis. Thirty-six children, with age at initial operation less than 6 months, were grouped based on length of ganglionated bowel excised (A [5 cm] and B [>5 cm]). No significant difference in the number of HAEC admissions during initial 2 years post-ERPT was seen between groups A (n = 18) and B (n = 18). The study had a power of 0.8 to detect a difference of 1 admission over 2 years.

CONCLUSIONS

Children diagnosed with Hirschsprung disease at younger ages are at a greater risk for postoperative enterocolitis. Excising a longer margin of ganglionated bowel (>5 cm) does not seem to be beneficial in decreasing HAEC admissions.

Long-term outcome, colonic motility, and sphincter performance after Swenson's procedure for Hirschsprung's disease: a single-center 2-decade experience with 346 cases

BACKGROUND

The aim of this study is to explore the long-term outcome and the colon and sphincter function in children undergoing the Swenson's operation for Hirschsprung's disease (HD).

METHODS

Three hundred forty-six children (266 males and 80 females) undergoing Swenson's operation for HD for 8 to 20 years were followed up. Barium enema and defecography, total and segmental colonic transit time with the simplified radioopaque markers, and the anorectal vector manometry were used.

RESULTS

Stooling patterns were fair in most patients, and the functional examinations were abnormal in few cases.

CONCLUSIONS

The long-term outcome is satisfactory in most of the children undergoing the Swenson's operation for HD, but it is still not as good as what the surgeons have expected. This is probably because of the abnormal colonic motility and/or the dysfunctions of the internal anal sphincter.

Long-term results of bowel function after treatment for Hirschsprung's disease: a 29-year review

Although various surgical procedures have been described to treat Hirschsprung's disease (HD), few studies have evaluated the long-term results of these children. The purpose of this study was to assess the long-term clinical outcome and bowel function of patients with HD. The hospital records of 259 consecutive patients with a confirmed histological diagnosis of HD during 1975-2003 were examined. Data was assessed for age at presentation, sex, clinical presentation, associated anomalies, level of aganglionosis, surgical procedures, complications and bowel function. Follow up was carried out by personal/telephone interviews with patients or their parents. Of the 259 patients with HD, 200 were males (77.2%) and 59 females (22.8%). Intestinal obstruction was the presenting feature in 147 patients (56.8%), intestinal perforation in 5 (1.9%), enterocolitis in 30 (11.6%) and constipation in 77 (29.7%). Thirty-nine patients (15.1%) had associated Down's syndrome. Two hundred and nine patients (80.7%) had rectosigmoid disease, 31 (12%) had long segment disease and 19 (7.3%) had total colonic aganglionosis. Forty-three patients (16.6%) had preoperative enterocolitis. Primary colostomy was performed in 160 patients and a primary pull through in 90. Seven patients had a sphincteromyectomy for ultrashort HD. Two patients died prior to treatment. Various pull through procedures were performed in these patients. Postoperative complications included: pelvic abcess in 2, rectal stricture in 10, perianal excoriation in 7, anastomotic leak in 8, intestinal obstruction in 3, wound dehiscence in 1, stomal prolapse/stenosis in 5, rectovesical fistula in 2 and enterocolitis in 56. Five patients underwent a redo pull through and 46 required a post pull through sphincterectomy. At the time of follow-up, 27 were lost to follow-up, 9 died, 18 had permanent stomas and 4 were too young to assess bowel function. Of the remaining 194 patients, bowel function was normal in 132 (68%). Twenty patients (10.3%) had soiling and 42 (21.7%) had constipation requiring laxatives or enemas. There was no difference in bowel function in relation to type of pull through operation. Only 34% of patients with Down's syndrome had normal continence. The majority of patients with HD continue to have disturbances of bowel function for many years before attaining normal continence.

Long-term outcome of patients with enterocolitis complicating Hirschsprung's disease

Enterocolitis remains the most serious complication of Hirschsprung's disease (HD). The purpose of this study was to evaluate the risk factors in the development of enterocolitis and the long-term outcome in these patients. The hospital records of 259 consecutive patients with HD during 1975-2003 were examined. The data was analysed for age at presentation, associated anomalies, level of aganglionosis, clinical features, number of episodes of enterocolitis, type of pullthrough, necessity for post-pullthrough sphincterectomy. Follow up was carried out by personal interviews and interviews over the telephone with patients/parents. Enterocolitis was diagnosed on the basis of clinical features of diarrhoea, pyrexia, abdominal distention and vomiting. Of the 259 patients with HD, 74 patients (28.5%) were found to have enterocolitis. Out of 39 patients with Down's syndrome and HD, 19 (48%) had enterocolitis. Fifteen (20%) patients had other associated anomalies. Fifty-six patients (75.6%) were male and 18 (24.3%) were female. In 30 patients enterocolitis was the presenting feature in the neonatal period, 22 of which presented in the first 2 weeks of life. Fifty-six patients (75.6%) had rectosigmoid disease and 18 (24.3%) had long segment disease or total colonic aganglionosis. Eighteen (24.3%) had only preoperative enterocolitis and 31(41.8%) had only postoperative enterocolitis. Twenty-five (33.7%) had both pre- and post-operative enterocolitis. Twenty (27%) patients had more than 2 episodes of enterocolitis. Various pullthrough procedures were performed. Twenty-six patients (35.1%) required internal sphinctermyectomy to treat the enterocolitis. At the time of follow-up, 16 patients were lost to follow-up. Of the remaining 58 patients, 3 patients died, 2 due to enterocolitis and 1 due to sepsis. Six patients remained with a stoma. Twenty-two patients were continent and were stooling normally, but 14 of these were on laxatives for several years after pullthrough procedure. The mean age at achieving full continence was 4.95 years in the 22 patients with normal bowel function. Nineteen patients are still on laxatives and 8 patients are soiling. Eight patients continue to have multiple recurrent episodes of enterocolitis at follow-up. Down's syndrome is an important risk factor in the development of enterocolitis. The majority of patients with enterocolitis complicating HD continue to have disturbances of bowel function many years after surgery for HD.