Enterocolitis associated with Hirschsprung's disease: a clinical histopathological correlative study

Postoperative Hirschsprung's associated enterocolitis (HAEC): transition zone as putative histopathological predictive factor

AIMS

Hirschsprung's-associated enterocolitis (HAEC) is the most severe complication of Hirschsprung disease (HD), and its pathogenesis is still unknown. Length of transition zone (TZ) interposed between aganglionic and normal bowel has been poorly explored as predictor for postoperative HAEC (post-HAEC). This study aimed to identify potential predictive factors for post-HAEC, with a particular focus on histopathological findings.

METHODS

Data from Hirschsprung patients treated in a single Italian centre between 2010 and 2022 with a follow-up >6 months were collected. Thorough histopathological examination of the resected bowel was conducted, focusing on length of TZ and aganglionic bowel.The degree of inflammatory changes in ganglionic resected bowel was further obtained. Ultra-long HD, total colonic aganglionosis and ultra-short HD were excluded. Bivariate and multivariate regression analysis were performed.

RESULTS

Thirty-one patients were included; 5 experienced preoperative HAEC (pre-HAEC) and later post-HAEC (16.1%), further 10 patients developed post-HAEC (total post-HAEC 48.38%). Pre-HAEC-history and a TZ<2.25 cm correlated with an early development of post-HAEC. Multivariate analysis identified a TZ<2.25 cm as an independent post-HAEC predictive factor (p=0.0096). Inflammation within the ganglionic zone and a TZ<2.25 cm correlated with higher risk of post-HAEC (p=0.0074, 0.001, respectively). Severe post-HAEC more frequently occurred in patients with pre-HAEC (p=0.011), histological inflammation (p=0.0009) and short TZ (p=0.0015).

CONCLUSIONS

This study suggests that TZ<2.25 cm predicts the risk of post-HAEC. Preoperative clinical and histopathology inflammation may predispose to worst post-HAEC. Readily available histopathological findings might help identifying patients at higher risk for HAEC and implementing prevention strategies.

A unicentric cross-sectional observational study on chronic intestinal inflammation in total colonic aganglionosis: beware of an underestimated condition

BACKGROUND

Inflammatory Bowel Diseases (IBD) are known to occur in association with Hirschsprung disease (HSCR). Most of cases are represented by Crohn Disease (CD) occurring in patients with Total Colonic Aganglionosis (TCSA) with an estimated prevalence of around 2%. Based on these considerations and on a number of provisional data belonging to our Center for Digestive Diseases, we developed a unicentric cross-sectional observational study aimed at describing phenotype, genotype, pathology and metagenomics of all patients with TCSA and Crohn-like lesions.

RESULTS

Out of a series of 62 eligible TCSA patients, 48 fulfilled inclusion criteria and were enrolled in the study. Ten patients did not complete the study due to non-compliance or withdrawal of consent and were subsequently dropped out. A total of 38 patients completed the study. All patients were tested for chronic intestinal inflammation by a combination of fecal calprotectine (FC) or occult fecal blood (OFB) and underwent fecal metagenomics. Nineteen (50%) tested positive for FC, OFB, or both and subsequently underwent retrograde ileoscopy. Fourteen patients (36.8%) presented Crohn-like lesions, occurring after a median of 11.5 years after surgery (range 8 months - 21.5 years). No statistically significant differences regarding demographic, phenotype and genotype were observed comparing patients with and without lesions, except for need for blood transfusion that was more frequent in those with lesions. Faecal microbiome of patients with lesions (not that of caregivers) was less biodiverse and characterized by a reduction of Bacteroidetes, and an overabundance of Proteobacteria. FC tested negative in 3/14 patients with lesions (21%).

CONCLUSIONS

Our study demonstrated an impressive 10-folds higher incidence of chronic inflammation in TCSA. Up to 50% of patients may develop IBD-like lesions postoperatively. Nonetheless, we failed in identifying specific risk factors to be used to implement prevention strategies. Based on the results of our study, we suggest screening all TCSA patients with retrograde ileoscopy regardless of FC/OFB values. The frequency of endoscopic assessments and the role of FC/OFB screening in prompting endoscopy is yet to be determined.

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.

Routine botulinum toxin injection one month after a Swenson pull-through does not change the incidence of Hirschsprung associated enterocolitis

PURPOSE

Patients with Hirschsprung disease (HD) are at risk of Hirschsprung associated enterocolitis (HAEC) following pull-through. The purpose of this study was to determine if routine Botulinum toxin (BT) injected one-month post pull-through decreases the incidence of HAEC.

METHODS

We reviewed patients who underwent a primary (not redo) pull-through operation for HD between April 2014 to December 2019. Over the most recent 18 months, BT was administered routinely one-month post-pull-through procedure; these patients were compared to the prior group that did not receive routine BT. A HAEC episode was defined as one that required initiation of treatment for obstructive symptoms in the inpatient or outpatient setting with antibiotics and irrigations. Categorical variables were compared using the nonparametric chi-square test or Fisher's exact test. Continuous variables were compared using the two-tailed Student's t-test. P-value <0.05 was determined to be statistically significant.

RESULTS

A total of 70 patients underwent Swenson pull-through during the study period (52% male). There were no statistically significant differences in demographics in the BT vs. non-BT group. Routine post-pull-through BT was given in 28 patients and did not significantly change HAEC incidence compared to the non-BT group (12/28, 43% vs. 16/42, 38%. P = 0.691). Of note, the BT group patients developed HAEC significantly sooner than the patients in the non-BT group (37.5 days vs. 253 days, p = 0.029). More patients in the BT group (n = 18, 64%) required at least one subsequent BT injection compared to the patients in the non-BT group (n = 11, 26%. P = 0.001).

CONCLUSIONS

We conclude that routine postoperative botulinum toxin injection given one month postoperatively from Swenson pull-through did not change the incidence of HAEC. A prospective controlled study is necessary to confirm these findings.

Different Fecal Microbiota in Hirschsprung's Patients With and Without Associated Enterocolitis

Background and Objectives

Patients with Hirschsprung's disease are at risk of developing Hirschsprung-associated enterocolitis, especially in the first 2 years of life. The pathophysiology of this inflammatory disease remains unclear, and intestinal dysbiosis has been proposed in the last decade. The primary objective of this study was to evaluate in a large cohort if Hirschsprung-associated enterocolitis was associated with alterations of fecal bacterial composition compared with HD without enterocolitis in different age groups.

Methods

We analyzed the fecal microbiota structure of 103 Hirschsprung patients from 3 months to 16 years of age, all of whom had completed definitive surgery for rectosigmoid Hirschsprung. 16S rRNA gene sequencing allowed us to compare the microbiota composition between Hirschsprung's disease patients with (HAEC group) or without enterocolitis (HD group) in different age groups (0-2, 2-6, 6-12, and 12-16 years).

Results

Richness and diversity increased with age group but did not differ between HD and HAEC patients, irrespective of the age group. Relative abundance of Actinobacteria was lower in HAEC than in HD patients under 2 years of age (-66%, P = 0.045). Multivariate analysis by linear models (MaAsLin) considering sex, medications, birth mode, breast-feeding, and the Bristol stool scale, as well as surgery parameters, highlighted Flavonifractor plautii and Eggerthella lenta, as well as Ruminococcus gnavus group, as positively associated with Hirschsprung-associated enterocolitis in the 0-2 years age group.

Conclusion

Hirschsprung-associated enterocolitis was associated with features of intestinal dysbiosis in infants (0-2 years) but not in older patients. This could explain the highest rate of enterocolitis in this age group.

Clinical Trial Registration

https://clinicaltrials.gov/ct2/show/NCT02857205, MICROPRUNG, NCT02857205, 02/08/2016.

Evaluation and treatment of the post pull-through Hirschsprung patient who is not doing well; Update for 2022

After operative intervention for Hirschsprung disease (HD) a child should thrive, be fecally continent, and avoid recurrent episodes of abdominal distention and enterocolitis. This is unfortunately not the case for a significant number of patients who struggle following their pull-through procedure. Many clinicians are puzzled by these outcomes as they can occur in patients who they believe have had a technically satisfactory described operation. This review presents an organized approach to the evaluation and treatment of the post HD pull-through patient who is not doing well. Patients with HD who have problems after their initial operation can have: (1) fecal incontinence, (2) obstructive symptoms, and (3) recurrent episodes of enterocolitis (a more severe subset of obstructive symptoms). After employing a systematic diagnostic approach, successful treatments can be implemented in almost every case. Patients may need medical management (behavioral interventions, dietary changes, laxatives, or mechanical emptying of the colon), a reoperation when a specific anatomic or pathologic cause is identified, or botulinum toxin when non-relaxing sphincters are the cause of the obstructive symptoms or recurrent enterocolitis.

Cholinergic Signaling Attenuates Pro-Inflammatory Interleukin-8 Response in Colonic Epithelial Cells

Infants affected by Hirschsprung disease (HSCR), a neurodevelopmental congenital disorder, lack ganglia of the intrinsic enteric nervous system (aganglionosis) in a variable length of the colon, and are prone to developing severe Hirschsprung-associated enterocolitis (HAEC). HSCR patients typically show abnormal dense innervation of extrinsic cholinergic nerve fibers throughout the aganglionic rectosigmoid. Cholinergic signaling has been reported to reduce inflammatory response. Consequently, a sparse extrinsic cholinergic innervation in the mucosa of the rectosigmoid correlates with increased inflammatory immune cell frequencies and higher incidence of HAEC in HSCR patients. However, whether cholinergic signals influence the pro-inflammatory immune response of intestinal epithelial cells (IEC) is unknown. Here, we analyzed colonic IEC isolated from 43 HSCR patients with either a low or high mucosal cholinergic innervation density (fiber-low versus fiber-high) as well as from control tissue. Compared to fiber-high samples, IEC purified from fiber-low rectosigmoid expressed significantly higher levels of IL-8 but not TNF-α, IL-10, TGF-β1, Muc-2 or tight junction proteins. IEC from fiber-low rectosigmoid showed higher IL-8 protein concentrations in cell lysates as well as prominent IL-8 immunoreactivity compared to IEC from fiber-high tissue. Using the human colonic IEC cell line SW480 we demonstrated that cholinergic signals suppress lipopolysaccharide-induced IL-8 secretion via the alpha 7 nicotinic acetylcholine receptor (a7nAChR). In conclusion, we showed for the first time that the presence of a dense mucosal cholinergic innervation is associated with decreased secretion of IEC-derived pro-inflammatory IL-8 in the rectosigmoid of HSCR patients likely dependent on a7nAChR activation. Owing to the association between IL-8 and enterocolitis-prone, fiber-low HSCR patients, targeted therapies against IL-8 might be a promising immunotherapy candidate for HAEC treatment.

Evaluation and Management of Persistent Problems After Surgery for Hirschsprung Disease in a Child

PURPOSE OF REVIEW

Ideally, after operative intervention, a child born with Hirschsprung disease (HD) should thrive, achieve fecal continence, and avoid recurrent episodes of abdominal distention and enterocolitis. However, a significant number of patients continue to struggle following their pull-through procedure. The purpose of this review is to present an organized and practical approach to the evaluation and management of the symptomatic patient post pull-through operation for HD.

RECENT FINDINGS

Children diagnosed with HD who are not doing well after their initial operation can be categorized in three distinct groups: (1) those that have fecal incontinence, (2) those with obstructive symptoms, and (3) those with recurrent episodes of enterocolitis. It is important to have a systematic diagnostic approach for these patients based on a comprehensive protocol. All three of these patient groups can be treated with a combination of either medical management, reoperation when a specific anatomic or pathologic etiology is identified, or botulinum toxin for non-relaxing sphincters contributing to the obstructive symptoms or recurrent enterocolitis. For patients not doing well after their initial pull-through, a systematic workup should be employed to determine the etiology. Once identified, a multidisciplinary and organized approach to management of the symptomatic patients can alleviate most post pull-through symptoms.

Comparison of Hirschsprung Disease Characteristics between Those with a History of Postoperative Enterocolitis and Those without: Results from the Pediatric Colorectal and Pelvic Learning Consortium

INTRODUCTION

 The current understanding of Hirschsprung-associated enterocolitis (HAEC) is based mainly on single-center, retrospective studies. The aims of this study are to determine risk factors for postoperative HAEC using the Pediatric Colorectal and Pelvic Learning Consortium (PCPLC) database.

MATERIALS AND METHODS

 We performed a multicenter, retrospective, case-control study of children with Hirschsprung disease (HD) who had undergone a pull-through procedure and were evaluated at a PCPLC member site between February 2017 and March 2020. The cohort with a history of postoperative HAEC was compared with that without postoperative episodes of HAEC to determine relevant associations with postoperative HAEC.

RESULTS

 One-hundred forty of 299 (46.8%) patients enrolled had a history of postoperative HAEC. Patients with a rectosigmoid transition zone had a lower association with postoperative HAEC as compared with those with a more proximal transition zone (odds ratio [OR]: 0.46, 95% confidence interval [CI]: 0.26, 0.84, p < 0.01). Private insurance was protective against postoperative HAEC on univariate analysis (OR: 0.62, 95% CI: 0.38, 0.99, p = 0.047), but not on multivariate analysis (OR: 0.62, 95% CI: 0.37, 1.04, p = 0.07). Preoperative HAEC was not associated with the development of postoperative HAEC.

CONCLUSION

 Patients with a rectosigmoid transition zone have less postoperative HAEC compared with patients with a more proximal transition zone. Multi-institutional collection of clinical information in patients with HD may allow for the identification of additional risk factors for HAEC and afford the opportunity to improve care.

Intestinal proinflammatory macrophages induce a phenotypic switch in interstitial cells of Cajal

Interstitial cells of Cajal (ICCs) are pacemaker cells in the intestine, and their function can be compromised by loss of C-KIT expression. Macrophage activation has been identified in intestine affected by Hirschsprung disease-associated enterocolitis (HAEC). In this study, we examined proinflammatory macrophage activation and explored the mechanisms by which it downregulates C-KIT expression in ICCs in colon affected by HAEC. We found that macrophage activation and TNF-α production were dramatically increased in the proximal dilated colon of HAEC patients and 3-week-old Ednrb-/- mice. Moreover, ICCs lost their C-KIT+ phenotype in the dilated colon, resulting in damaged pacemaker function and intestinal dysmotility. However, macrophage depletion or TNF-α neutralization led to recovery of ICC phenotype and restored their pacemaker function. In isolated ICCs, TNF-α-mediated phosphorylation of p65 induced overexpression of microRNA-221 (miR-221), resulting in suppression of C-KIT expression and pacemaker currents. We also identified a TNF-α/NF-κB/miR-221 pathway that downregulated C-KIT expression in ICCs in the colon affected by HAEC. These findings suggest the important roles of proinflammatory macrophage activation in a phenotypic switch of ICCs, representing a promising therapeutic target for HAEC.

Evidence for Differentiation of Colon Tissue Microbiota in Patients with and without Postoperative Hirschsprung's Associated Enterocolitis: A Pilot Study

PURPOSE

To investigate the differences in the colon microbiota composition of Hirschsprung's disease (HSCR) patients with and without a history of postoperative Hirschsprung's associated enterocolitis (HAEC).

METHODS

Colon tissue microbiota was characterized by bacterial deoxyribonucleic acid (DNA) extraction and 16S rDNA sequencing for taxonomic classification and comparison.

RESULTS

The sequence diversity richness within samples was significantly higher in samples from patients with a history of postoperative HAEC. We observed an increased relative abundance of the phyla Bacteroidetes, Firmicutes and Cyanobacteria in HAEC patients and Fusobacteria, Actinobacteria and Proteobacteria in HSCR patients and, an increased relative abundance of the genera Dolosigranulum, Roseouria and Streptococcus in HAEC patients and Propionibacterium and Delftia in HSCR patients.

CONCLUSION

Our findings provide evidence that the colon tissue microbiota composition is different in HSCR patients with and without postoperative HAEC.

Colonoscopic Diagnosis of Postoperative Gastrointestinal Bleeding in Patients With Hirschsprung's Disease

Aim: Postoperative lower gastrointestinal bleeding in children with Hirschsprung's Disease (HSCR) is a non-specific symptom, which may be caused by various etiologies. Our current study aims to utilize colonoscopy to diagnose the causes of postoperative hematochezia and to analyze its feasibility, accuracy, and safety. Methods: Twenty-four patients with HSCR with postoperative lower gastrointestinal bleeding or occult blood in the stool were enrolled in this study. The postoperative onset duration, age at examination, accompanied anomalies were recorded. After bowel preparation, all patients underwent colonoscopy. According to visual findings, mucosal biopsy was performed, followed by pathological diagnosis. Further treatment was determined according to the visual findings and pathological diagnosis. All patients were followed up for 6 months including therapeutic outcomes and recurrence of symptoms. Results: The mean onset duration was (221.3 ± 216.8) days postoperatively (ranging from 25 to 768 days). The mean age at examination was (41.0 ± 29.4) months. There was no significant difference in the onset days among each group (all, p > 0.05). Based on visual and pathological findings, there were 11 cases of HSCR associated enterocolitis (HAEC), 4 cases of anastomotic leakage, 7 cases of anastomotic inflammation, 1 case of juvenile polyp, and 1 case of inflammatory pseudopolyp. Intraluminal saline irrigation, thrombin treatment or colorectal polyp electrocision was performed according to intraoperative diagnosis. Patients with HEAC and anastomotic inflammation underwent antibiotics therapy and colorectal irrigation. Patients with leakage underwent reoperation. The highest incidence of accompanied symptoms of diarrhea existed in HEAC group (p = 0.02) and fever in leakage group (p = 0.02), respectively. No perforation or aggravated bleeding occurs in any patients. All patients gained uneventful recovery during follow-up period. Conclusions: Colonoscopy is a safe, accurate and timely examination for HSCR patients with postoperative lower gastrointestinal bleeding. The visual findings and biopsy may provide accurate diagnosis and guide treatment for this subset of patients.

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.

First Report of Congenital Short Bowel Syndrome in an Iranian Patient Caused by a Mutation in the CLMP Gene

Congenital short bowel syndrome (CSBS) is a rare congenital neonatal disorder. CSBS results from intestinal impairment during embryogenesis. Mutated CXADR-like membrane protein ( CLMP ) and Filamin A genes are involved in the cause of CSBS. In this study, due to our misdiagnosis, we had to perform whole exome sequencing on the patient, and also we implemented cosegregation analysis on his parents with consanguineous marriage and also parents' mothers. We identified a homozygous loss of function mutation in the CLMP gene in exon 5 (c.664C > T, p.R222X). Also, both parents and grandmothers of the proband were heterozygous for this mutation. Loss of function mutation in CLMP causes CSBS, leading to impaired intestinal development.

Transanal endorectal stepwise gradient muscular cuff cutting pull-through method: Technique refinements and comparison with laparoscopy-assisted procedures

In all existing radical resection procedures available for Hirschprung's disease (HD), the muscular cuff has been retained. In recent years, our study group has modified the procedure using a stepwise gradient muscular cuff cutting pull-through method for the treatment of HD. The objective of the present study was to assess patient prognosis following the use of the transanal endorectal pull-through (TEPT) method or the laparoscopy-assisted pull-through (LPT) method and to provide evidence to assist in clinical decisions. The medical records of 172 patients (age, ≥3 years) who underwent TEPT or LPT for HD between September 2003 and August 2014 at the Pediatric Surgery Department of The Affiliated Hospital of Zunyi Medical College (Zunyi, China) were reviewed (TEPT, n=94; LPT, n=78). Preoperative, intraoperative and post-operative data for the subjects involved were recorded. Each patient's family was interviewed using a uniform 12-item post-pull-through long-term outcome questionnaire, which was scored in order to compare the short and long-term treatment outcomes of patients in each group. Patients in the LPT group had significantly prolonged operating times, reduced intraoperative blood loss and perioperative transfusion rates and shorter anal dissection times. Furthermore, the oral feeding time and length of hospital stay were similar between groups. There were no significant differences in early complications between the groups. No significant differences in late complications, including anastomotic stricture and enterocolitis were observed; however, the soiling and constipation rates were significantly higher in the TEPT group compared with the LPT group. The stool pattern score was not significantly different between groups, while the frequency of bowel movements in the LPT group was significantly higher compared with the TEPT group from 9-24 months post-surgery. The stepwise gradient muscular cuff cutting pull-through method demonstrated a good safety profile and efficacy with regard to the long-term outcomes of patients with HD. These results support the clinical application of LPT as a promising surgical approach for children with HD.

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.

Isolated Ileal Perforation in Infancy: A Lethal Initial Presentation of Hirschsprung's Disease

Arare case of ileal perforation, as a fatal initial presentation of total colonic aganglionosis (TCA) in infancy is reported. A 10-week-old boy, was brought to the emergency department with symptoms of complicated intestinal obstruction. He looked ill, was lethargic, markedly dehydrated and had a severely distended abdomen. An abdominal X-ray revealed multiple air fluid levels seen in a distended small intestine. During exploratory laparotomy the ileum was massively dilated with distal segment perforation. Ileal perforation repair was performed. A totally collapsed microcolon was identified. Biopsies were taken from the high rectum, sigmoid and hepatic flexure. Appendectomy and ileostomy were performed. All biopsies, as well as the appendix, showed absence of ganglion cells. Despite this procedure the patient progressively deteriorated and later died due to sepsis. Ileal perforation in infants is a rare, but potentially fatal initial presentation of TCA. Early detection is essential to prevent life-threatening complications.

Disruptions of the intestinal microbiome in necrotizing enterocolitis, short bowel syndrome, and Hirschsprung's associated enterocolitis

Next generation sequencing techniques are currently revealing novel insight into the microbiome of the human gut. This new area of research seems especially relevant for neonatal diseases, because the development of the intestinal microbiome already starts in the perinatal period and preterm infants with a still immature gut associated immune system may be harmed by a dysproportional microbial colonization. For most gastrointestinal diseases requiring pediatric surgery there is very limited information about the role of the intestinal microbiome. This review aims to summarize the current knowledge and outline future perspectives for important pathologies like necrotizing enterocolitis (NEC) of the newborn, short bowel syndrome (SBS), and Hirschsprung’s disease associated enterocolitis (HAEC). Only studies applying next generation sequencing techniques to analyze the diversity of the intestinal microbiome were included. In NEC patients intestinal dysbiosis could already be detected prior to any clinical evidence of the disease resulting in a reduction of the bacterial diversity. In SBS patients the diversity seems to be reduced compared to controls. In children with Hirschsprung’s disease the intestinal microbiome differs between those with and without episodes of enterocolitis. One common finding for all three diseases seems to be an overabundance of Proteobacteria. However, most human studies are based on fecal samples and experimental data question whether fecal samples actually represent the microbiome at the site of the diseased bowel and whether the luminal (transient) microbiome compares to the mucosal (resident) microbiome. In conclusion current studies already allow a preliminary understanding of the potential role of the intestinal microbiome in pediatric surgical diseases. Future investigations could clarify the interface between the intestinal epithelium, its immunological competence and mucosal microbiome. Advances in this field may have an impact on the understanding and non-operative treatment of such diseases in infancy.

Long-term results of total colonic agangliosis patients treated by preservation of the aganglionic right hemicolon and the ileo-cecal valve

PURPOSE

In 1989, Sauer introduced a technique to treat patients with total colonic aganglionosis (TCA) where he preserved the ileo-cecal valve and the right hemicolon to retain water and electrolyte absorption. This report examines the long-term outcome of patients who underwent this technique.

METHODS

All TCA patients treated between 1981 and 2005 according to Sauer were invited in 2013 to participate in a questionnaire survey to assess their long-term outcome focusing on bowel function and quality of life (QoL), using standardized scores.

RESULTS

Of eight TCA patients (2 females, 6 males), seven participated in the follow-up survey (median follow-up time 13.5 years (range 8-31.6). Early postoperative complications involving bouts of enterocolitis in 3 and anal strictures in 5 patients ceased with age. Bowel movements ranged from median 3-4 times a day (range 1-8). Bowel-function score (BFS) was reduced in 6 patients (median 16 points, range 8-19, max 20), who also reported soiling incidences with the need for night-time protective aids in two. QoL assessment, however, documented a good outcome with a median score of 10 points (range 7-13, max 13).

CONCLUSION

This long-term investigation of TCA patients treated according to Sauer's technique documented a good QoL despite a reduced BFS.

Advances in Hirschsprung disease genetics and treatment strategies: an update for the primary care pediatrician

Hirschsprung disease (HSCR) is a multigenic condition with variable presentation. Most commonly, it presents in the neonatal period as a functional intestinal obstruction secondary to failure of caudal migration of the enteric nervous system. Classically, this manifests as dilated proximal bowel and constricted distal bowel with absent ganglia and hypertrophic nerve trunks. When recognized early, medical and surgical therapies can be instituted to minimize associated morbidity and mortality. This article reviews current understanding of the etiology of HSCR, its multigenic associations, the historical evolution of HSCR diagnosis and treatment, and current HSCR therapies.

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.

Induction of RET dependent and independent pro-inflammatory programs in human peripheral blood mononuclear cells from Hirschsprung patients

Hirschsprung disease (HSCR) is a rare congenital anomaly characterized by the absence of enteric ganglia in the distal intestinal tract. While classified as a multigenic disorder, the altered function of the RET tyrosine kinase receptor is responsible for the majority of the pathogenesis of HSCR. Recent evidence demonstrate a strong association between RET and the homeostasis of immune system. Here, we utilize a unique cohort of fifty HSCR patients to fully characterize the expression of RET receptor on both innate (monocytes and Natural Killer lymphocytes) and adaptive (B and T lymphocytes) human peripheral blood mononuclear cells (PBMCs) and to explore the role of RET signaling in the immune system. We show that the increased expression of RET receptor on immune cell subsets from HSCR individuals correlates with the presence of loss-of-function RET mutations. Moreover, we demonstrate that the engagement of RET on PBMCs induces the modulation of several inflammatory genes. In particular, RET stimulation with glial-cell line derived neurotrophic factor family (GDNF) and glycosyl-phosphatidylinositol membrane anchored co-receptor α1 (GFRα1) trigger the up-modulation of genes encoding either for chemokines (CCL20, CCL2, CCL3, CCL4, CCL7, CXCL1) and cytokines (IL-1β, IL-6 and IL-8) and the down-regulation of chemokine/cytokine receptors (CCR2 and IL8-Rα). Although at different levels, the modulation of these “RET-dependent genes” occurs in both healthy donors and HSCR patients. We also describe another set of genes that, independently from RET stimulation, are differently regulated in healthy donors versus HSCR patients. Among these “RET-independent genes”, there are CSF-1R, IL1-R1, IL1-R2 and TGFβ-1, whose levels of transcripts were lower in HSCR patients compared to healthy donors, thus suggesting aberrancies of inflammatory responses at mucosal level. Overall our results demonstrate that immune system actively participates in the physiopathology of HSCR disease by modulating inflammatory programs that are either dependent or independent from RET signaling.

Short bowel syndrome in the NICU

Short bowel syndrome (SBS) is the most common cause of intestinal failure in infants. In neonates and young infants, necrotizing enterocolitis, gastroschisis, intestinal atresia, and intestinal malrotation/volvulus are the leading causes of SBS. Following an acute postsurgical phase, the residual gastrointestinal tract adapts with reorganization of the crypt-villus histoarchitecture and functional changes in nutrient absorption and motility. A cohesive, multidisciplinary approach can allow most neonates with SBS to transition to full enteral feeds and achieve normal growth and development. In this article, the clinical features, management, complications, and prognostic factors in SBS are reviewed.

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.

Total colonic aganglionosis in Hirschsprung disease

Total colonic aganglionosis (TCA) is a relatively uncommon form of Hirschsprung disease (HSCR), occurring in approximately 2%-13% of cases. It can probably be classified as TCA (defined as aganglionosis extending from the anus to at least the ileocecal valve, but not >50 cm proximal to the ileocecal valve) and total colonic and small bowel aganglionosis, which may involve a very long segment of aganglionosis. It is not yet clear whether TCA merely represents a long form of HSCR or a different expression of the disease. There are many differences between TCA and other forms of HSCR, which require explanation if its ubiquitous clinical features are to be understood. Clinically, TCA appears to represent a different spectrum of disease in terms of presentation and difficulties that may be experienced in diagnosis, suggesting a different pathophysiology from the more common forms of HSCR. There is also some evidence suggesting that instead of being purely congenital, it may represent certain different pathophysiologic mechanisms. This study, in addition to reviewing current understanding and differences between TCA and the more frequently encountered rectosigmoid (or short-segment) expression, correlates them with what is currently known about the genetic and molecular biological background. Moreover, it reviews current outcomes to find consensus on management.

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.

Mucosal healing in inflammatory bowel diseases: a systematic review

Recent studies have identified mucosal healing on endoscopy as a key prognostic parameter in the management of inflammatory bowel diseases (IBD), thus highlighting the role of endoscopy for monitoring of disease activity in IBD. In fact, mucosal healing has emerged as a key treatment goal in IBD that predicts sustained clinical remission and resection-free survival of patients. The structural basis of mucosal healing is an intact barrier function of the gut epithelium that prevents translocation of commensal bacteria into the mucosa and submucosa with subsequent immune cell activation. Thus, mucosal healing should be considered as an initial event in the suppression of inflammation of deeper layers of the bowel wall, rather than as a sign of complete healing of gut inflammation. In this systematic review, the clinical studies on mucosal healing are summarised and the effects of anti-inflammatory or immunosuppressive drugs such as 5-aminosalicylates, corticosteroids, azathioprine, ciclosporin and anti-TNF antibodies (adalimumab, certolizumab pegol, infliximab) on mucosal healing are discussed. Finally, the implications of mucosal healing for subsequent clinical management in patients with IBD are highlighted.

Intestinal aganglionosis is associated with early and sustained disruption of the colonic microbiome

BACKGROUND

Congenital aganglionosis (Hirschsprung's disease) results in colonic dysmotility and a risk for Hirschsprung's-associated enterocolitis (HAEC), whose cause is unknown. We hypothesized that aganglionosis leads to microbiome changes that may contribute to HAEC risk.

METHODS

Colon and fecal samples were collected from endothelin receptor B-null (Ednrb(-/-) ) mice, an established model of colorectal aganglionosis, at postnatal day 7 (P7), P20, and P24. We determined microbiome composition by 16S ribosomal RNA gene pyrosequencing and fecal metabolite profile by nuclear magnetic resonance spectroscopy.

KEY RESULTS

Wild-type (WT) mice exhibited increasing species diversity with age, with mutant mice possessing even greater diversity. WT and mutant microbiomes, both fecal and colonic, significantly segregated by principal coordinates analysis based on species composition at all ages examined. Importantly, mutant mice contained more Bacteroidetes and less Firmicutes than WT, with additional genus- and species-level differences observed. Notably, mutant P7 colon was dominated by coagulase-negative Staphylococcus species, which were rare in WT. Mutant fecal metabolite profiles also differed, particularly in the abundance of formate, a short-chain fatty acid product of microbial fermentation.

CONCLUSIONS & INFERENCES

Colorectal aganglionosis is associated with early and sustained disruption of the normal colonic and fecal microbiome, supporting the enteric nervous system as a determinant of microbiome composition. Furthermore, the differences observed suggest a potential contributory role for the microbiome in the etiology of HAEC. These findings provide a basis for further studies to determine the causative role of specific bacterial communities in HAEC and the potential to restore the normal microbiome in Hirschsprung's disease.

Total colonic aganglionosis: a systematic review and meta-analysis of long-term clinical outcome

PURPOSE

Total colonic aganglionosis (TCA) is a severe form of Hirschsprung's disease (HD), occurring in less than 10 % of the cases. It is a challenging surgical condition and outcomes of pull-through (PT) surgery are reported to be inferior to those in patients with recto-sigmoid HD. As even large centres only see a few patients with TCA, there is little information on the long-term outcome of patients after PT operation for TCA. The aim of this meta-analysis was to investigate the long-term clinical outcome in patients with TCA.

METHODS

MEDLINE(®) and EMBASE(®) databases were searched for relevant articles that reported the outcomes of patients with TCA published between 1980 and 2011. The search terms were "Hirschsprung's disease", "Total colonic aganglionosis" AND "Outcome". All published studies containing adequate clinical data for a mean follow-up period of not less than 4 years were included. Reference lists of retrieved articles were reviewed for additional cases. Detailed records of morbidity and mortality were extracted and analysed.

RESULTS

This search yielded 225 articles reporting on outcomes in TCA. Of these, 189 were excluded for having too short a follow-up period, small or single case series, inadequate clinical data and duplicated patient groups. Ultimately, 36 articles from 37 centres containing useful clinical information on the outcomes of TCA in 969 patients were identified. There were 152 early deaths prior to PT (15.7 %). Of 817 survivors, 739 underwent PT. The mortality rate for TCA post-PT was 5.7 %. The most frequently reported post-operative complication was enterocolitis in 42 % of the cases. 17.5 % of patients underwent subsequent major surgery including redo PT, stoma reformation or other laparotomy. Long-term follow-up data were available in 396 patients. Satisfactory or normal bowel control was reported in 60 % of the patients. Soiling, faecal incontinence or other poor outcome was reported in 33.5 % of the cases and 6.5 % of the patients had undergone conversion to a permanent ileostomy for post-operative complications.

CONCLUSION

This meta-analysis reveals that a large number of patients with TCA have long-term problems with bowel control.

Re-operation for Hirschsprung's disease: experience in 24 patients from China

PURPOSE

The aim of this study is to review the authors' 12-year experience with re-operative surgery for Hirschsprung's disease (HD) including indications of re-operation and surgical technique.

METHODS

We retrospectively reviewed the data of 24 patients who underwent re-operation from 1998 to 2010. The type of initial procedure, clinical presentations, indications and details of redo surgery, and the functional results were analyzed.

RESULTS

The primary operations performed on these patients included Duhamel (nine cases), Soave (12 cases), Swenson (one case) and Rehbein (two cases). The indications for re-operation were recurrent constipation due to severe anastomotic stricture (five cases), residual aganglionic segments (five cases) and gate syndrome after Duhamel procedure (five cases); fistula formation including rectocutaneous fistula (six cases), rectovaginal fistula (one case), complex fistula (two cases). The redo procedure ranged from posterior sagittal approach combined with laparotomy (seven cases), Soave procedure (seven cases, six conventional Soave + one transanal Soave), Duhamel procedure (one case), Rehbein procedure (three cases), re-using the stapling device (five cases), repairing the rectovaginal fistula via laparotomy (one case). We have followed up the patients for 7 months to 6 years (mean 2.5 years). After re-operation, in 22 patients older than 3 years, 19 (86.4%) have normal or near normal bowel habits with a stool frequency of 1-5 times per day, two have voluntary bowel movements but occasional soiling (once or twice per week) and without significant incontinence, one presented rectosacral fistula due to careless dilatation. There were no deaths.

CONCLUSION

Re-operation can work out the anatomical or pathological problems resulted from failed initial procedure and improve the patient's quality of life. Posterior sagittal approach, Soave and Duhamel are all safe and effective, but we still need to try our best to diminish the necessity of re-operation.

Residual aganglionosis after pull-through operation for Hirschsprung's disease: a systematic review and meta-analysis

PURPOSE

Most patients with Hirschsprung's disease (HD) have a satisfactory outcome after pull-through (PT) operation. However, some children continue to have persistent bowel symptoms after the initial operation and may require redo PT. Redo PT operation in HD is usually indicated for anastomotic strictures or residual aganglionosis (RA). We designed this meta-analysis to determine the incidence and outcome of RA among patients with HD following PT operation.

METHODS

A meta-analysis of redo PT operations for HD reported in the literature between 1985 and 2011 was performed. Detailed information was recorded in patients with RA and transition-zone bowel (TZB), including recurrent bowel problems, histological findings on repeat rectal biopsy, type of redo PT operation and outcome.

RESULTS

Twenty-nine articles reported 555 patients with redo PT operations. 193 (34.8%) patients demonstrated abnormal histological findings on rectal biopsy with 144 patients showing RA and 49 patients showing TZB. These 193 patients presented with persistent constipation (n = 135), recurrent enterocolitis (n = 45) and abnormal histology of the pulled-through bowel (n = 13). Mean age at redo PT was 4.4 years (range 4 months-17 years). Redo procedures were Duhamel (n = 57), transanal endorectal PT (n = 40), Soave (n = 35), Swenson (n = 10), posterior sagittal approach (n = 1) and not reported (n = 50). Follow-up information after redo PT was available in 134 (69.4%) patients and not available in 59 patients. Of the 134 patients, 99 (73.9%) patients had normal bowel habits, 19 patients had persistent constipation/soiling and 16 patients had recurrent enterocolitis.

CONCLUSION

This meta-analysis reveals that RA and TZB are the underlying causes of persistent bowel symptoms in one-third of all patients with HD requiring redo PT operation. Most patients have a satisfactory outcome after redo operation. Rectal biopsy should be performed in all patients with recurrent bowel problems after PT operation.

Splenic lymphopenia in the endothelin receptor B-null mouse: implications for Hirschsprung associated enterocolitis

PURPOSE

The aim of the study was to describe and characterize a novel small spleen phenotype with splenic lymphopenia in the Ednrb-null (Ednrb-/-) mouse with aganglionosis known to also develop enterocolitis.

METHODS

We compared spleen weight as a percent of body weight from Ednrb+/+, Ednrb+/-, and Ednrb-/- mice to quantify our initial observation. Splenic microarchitecture of Ednrb+/+ and Ednrb-/- mice was assessed using both H and E staining and immunofluorescence staining for CD45R+ (B cells) and CD3+ (T cells) on tissue sections. To identify and quantify cell type, flow cytometry for CD19+ (mature B cells), CD4+ and CD8+ (T cells) was performed on the splenocytes of Ednrb+/+ and Ednrb-/- mice and compared with student's t test. A separate cohort of Ednrb+/+ and Ednrb-/- mice was killed and splenocytes were analyzed by flow cytometry, and proximal colon was histopathologically graded for enterocolitis. Spearman's rank correlations comparing total splenocyte and CD19+ cell counts with enterocolitis scores were performed.

RESULTS

We found that the mean spleen weight expressed as a percent of body weight for Ednrb+/+ and Ednrb-/- mice was 0.72 and 0.25%, respectively (P < 0.001), at 25 days of age. In addition, the Ednrb-/- spleens also had markedly abnormal splenic microarchitecture with lymphopenia, and relative reduction of B cells compared to T cells. FACS of splenocytes revealed a 5 to 20-fold reduction in total cell number, CD19+, CD4+, and CD8+ of the Ednrb-/- mice compared to the Ednrb+/+ littermates (P < 0.01). We also found a strong inverse correlation of total spleen and CD19+ cell counts with histopathological enterocolitis scores (r (s) = -0.43, P = 0.02), showing that mice with reduced cell counts also had increased severity of enterocolitis.

CONCLUSION

The small spleen immunophenotype in the Ednrb-/- mouse suggests that Ednrb-dependent signaling may be required for normal spleen development. These results raise the possibility that primary immune abnormalities may contribute at least in part to some enterocolitis. At present, our data suggest intriguing new potential explanations for HAEC in Hirschsprung patients.

Endorectal pull-through for Hirschsprung's disease-a multicenter, long-term comparison of results: transanal vs transabdominal approach

PURPOSE

Previous studies have reported decreased continence in patients undergoing transanal endorectal pull-through (TERP) for Hirschsprung's disease compared to the older transabdominal approach (TAA). To address this, we examined long-term stooling outcomes in a large, multicenter cohort of patients undergoing either TERP or TAA.

METHODS

Data were collected from 5 large pediatric institutions. Patient families were surveyed using a stooling score system (0-40, best to worst total score). Inclusion criteria included patients older than 3 years and those who had more than 6 months of recovery after pull-through. Those with total colonic aganglionosis were excluded. Statistical analysis included univariate and multivariate linear regression (significance, P < .05).

RESULTS

Two hundred eighty-one patients underwent TERP (192) or TAA (89). Interviews were completed in 149 (104 [52%] TERP vs 45 [52%] TAA). The TAA group had a significantly greater number of daily bowel movements for each respective postoperative year and experienced more early complications (3% vs 1% with >1 complication; P = .061) and late complications (19% vs 4% with >1 complication; P < .001). Although the TAA group had a higher mean enterocolitis score (3.3 +/- 0.4 vs 1.8 +/- 0.2; P < .001), this was not borne out by multivariate regression analysis (P = .276). Parental survey showed that there were no significant differences between procedures in mean total, continence, or stooling pattern scores.

CONCLUSION

Transanal endorectal pull-through was associated with fewer complications and fewer episodes of enterocolitis. In contrast to prior studies, TERP patients did not have a higher rate of incontinence. These results support use of TERP as an excellent surgical approach for children with Hirschsprung's disease.

Evaluation and treatment of the patient with Hirschsprung disease who is not doing well after a pull-through procedure

Ideally, after operative management of Hirschsprung disease, a child should thrive, avoid recurrent episodes of abdominal distention and enterocolitis, and be fecally continent. However, there is a small group of patients that do not do well after their pull-through procedure. The purpose of this article is to describe our algorithm for the work-up and management of the post pull-through patient with Hirschsprung disease who is not doing well. These children can be categorized into 2 distinct groups: (1) those who are soiling, and (2) those who suffer from distention and enterocolitis. Both of these patient types can be systematically treated with a combination of bowel management, dietary changes, and laxatives, and, potentially, a redo operation, with the goal of having a clean, and happy child.

Genomics approach to the analysis of bacterial communities dynamics in Hirschsprung's disease-associated enterocolitis: a pilot study

INTRODUCTION

The most invalidating and life-threatening complication in Hirschsprung's disease patients (HSCR) is Hirschsprung's disease-associated enterocolitis (HAEC). The mechanisms underlying enterocolitis have not been identified. The limited knowledge of the role of intestinal microflora is in part due to the complexity of the intestinal microbiome and to the limitation of cultivation-based technologies, given that less than 25% of the intestinal bacterial species can be cultured.

MATERIALS AND METHODS

We used amplified ribosomal DNA restriction analysis (ARDRA) with four different restriction enzymes to study variations of microflora composition of the stools of a selected HSCR patient in different clinical conditions (acute phase vs. remission).

RESULTS

We assessed a total of 15 stool specimens belonging to the same 3-year-old male patient suffering from HSCR, which were harvested during 4 HAEC episodes and remission phases. Restriction analysis showed that HAEC episodes seem to cluster together at ARDRA analysis, thus suggesting a sort of predisposing bacterial community for HAEC development and the need for a microflora equilibrium to maintain wellness.

CONCLUSIONS

This approach proved to be effective, useful and powerful in assessing microflora dynamics and indicated that the differences in microflora associated with acute HAEC or remission are likely to result from a combination of disease activity and different antibiotic therapies. ARDRA proved to be useful in discriminating disease versus remission. Our findings indicated that HAEC results from a change in the equilibrium between bacterial species or from altered discrimination of harmless from harmful microorganisms, challenging the definition of pathogenic and non-pathogenic species. Based on these results, we propose ARDRA as a rapid inexpensive tool to assess microflora dynamics during HAEC episodes.

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.

Patterns of postoperative enterocolitis in children with Hirschsprung's disease combined with hypoganglionosis

OBJECTIVE

The relationship between postoperative enterocolitis (EC) and Hirschsprung's disease (HD) combined with hypoganglionosis (HYP) has not been thoroughly reported elsewhere. The aim of this study was to investigate the incidence of EC after operation in children with HD combined with HYP and to identify new strategies to prevent postoperative EC.

METHODS

From 1998 to 2005, 97 children with HD underwent the modified Swenson's procedure in this institute. They were classified into 2 groups based on pathologic investigation as follows: group A contained 70 patients with HD and group B contained 27 patients with HD complicated with HYP. The mean follow-up time from the time of the operation was 3.4 years (range, 1.5-8 years). The incidence of postoperative EC and anorectal functions were evaluated and compared between these 2 groups.

RESULTS

Eight cases (11.4%) in group A developed postoperative EC, whereas 11 (40.7%) in group B did so. The incidence of postoperative EC in group A was significantly lower than that in group B (P < .005). According to the Rintala scoring system, the percentage of patients with an excellent score in group A (85.7%) was significantly higher than that in group B (P < .05). The recurrence rate of constipation in group B was 14.8% (4/27), whereas it was 2.8% (2/70) in group A.

CONCLUSIONS

Postoperative EC is associated with retained proximal HYP, which suggests that HYP could be, at minimum, a predictive marker for this complication. Complete resection of HYP segment could potentially minimize the incidence of postoperative EC and alleviate the severity of EC.

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.

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.

Pediatric anorectal disorders

This article reports the clinical, physiopathologic, diagnostic, and therapeutic aspects of the most common anorectal disorders in children. In particular, it focuses on the differential diagnosis between organic and functional constipation. In addition, the authors separately examine some of the clinical conditions such as atopy, neurologic diseases, and anorectal malformations, in which chronic constipation may be an important clinical manifestation.

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.

Hirschsprung disease: do risk factors of poor surgical outcome exist?

INTRODUCTION

Long-term results after surgical treatment of Hirschsprung disease (HSCR) are not always as good as a surgeon may perceive. Several studies have tried to correlate preoperative features to the surgical outcome of HSCR, but none came to definitive conclusions. Our study is aimed at identifying risk factors of poorer long-term outcome after surgery for HSCR.

MATERIALS AND METHODS

One hundred two patients with HSCR were included. Eighty had rectosigmoid aganglionosis and 22 had total colonic aganglionosis (TCSA). Preoperative variables were sex, associated anomalies, delayed meconium passage, preoperative enterocolitis, preoperative bowel obstruction, age at surgery, and number of pull-through procedures performed. Outcome measures were surgical complications, postoperative enterocolitis, perineal excoriations, constipation, continence, psychological self acceptance, and patients' perspectives. These were evaluated with regard to preoperative features and length of aganglionosis.

RESULTS

Results of patients with TCSA proved to be significantly worse than those of patients with classic HSCR (constipation and poor continence excluded). Male patients with TCSA proved to have a significantly higher incidence of complications (100% vs 38.5%) and poor psychological self acceptance (100% vs 46.2%). Patients with associated anomalies (central nervous system) experienced a significantly higher incidence of postoperative constipation (43% vs 13%). Patients who described failure or delayed meconium passage complained of significantly worse continence (28.3% vs 7.1% of fair to poor continence). Preoperative enterocolitis proved to be significantly correlated to postoperative enterocolitis (16.4% vs 37.1%) and perineal excoriations (13.7% vs 30.9%). Patients with preoperative intestinal obstructions complained of significantly worse psychological self acceptance (37.8% vs 12.5%).

CONCLUSIONS

Length of aganglionosis has the greatest impact on overall surgical outcome of HSCR. Other minor risk factors have been identified, namely, male sex, associated central nervous system anomalies, failure to pass meconium, and preoperative enterocolitis occurrences. Age at surgery and redo procedures proved not to significantly interfere with the outcome. Our study provides comprehensive and useful data to inform parents and families of a baby with HSCR with regard to expected results and long-term outcomes of surgery basing on preoperative features. Further studies on larger series are strongly recommended.

Uncommon causes of postoperative chronic diarrhoea mimicking enterocolitis in Hirschsprung's disease: is there a role for digestive endoscopy?

Severe chronic diarrhoea secondary to enterocolitis is a severe complication of Hirschsprung's disease (HSCR). Persistent outlet obstruction, immunologic issues, and mucin/mucous imbalance can cooperate in the development of this complication. Furthermore, isolated reports described severe postoperative chronic diarrhoea mimicking enterocolitis in patients with sucrase-isomaltase deficiency, inflammatory bowel disease (IBD), or intestinal microvillus atrophy. This paper is aimed in describing three patients from our HSCR series who experienced severe chronic postoperative diarrhoea secondary to such uncommon associated anomalies: sucrase-isomaltase deficiency (one patient) and IBD (two patients). With an appropriate sucrose-free diet or immunosuppressive therapy these patients improved dramatically and their diarrhoea settled. These associated anomalies can be diagnosed with digestive endoscopies (both gastro-duodenoscopy and colonoscopy). Therefore, we developed a diagnostic and therapeutic algorithm for patients with chronic diarrhoea after a pull-through, which includes digestive endoscopy to be performed in selected cases.

Evaluation and management of persistent problems after surgery for Hirschsprung disease in a child

Hirschsprung disease occurs approximately once in every 5000 live-born infants. It is characterized by the absence of ganglion cells in the myenteric and submucosal plexuses of the intestine. Once the diagnosis of Hirschsprung disease has been made, most patients are now treated with a transanal approach to resection. We review the early and late postoperative complications. Late complications include persistent mechanical obstruction, recurrent or acquired aganglionosis, disordered motility in the proximal colon or small bowel, internal sphincter achalasia, or functional megacolon caused by stool-holding behavior. These children require complex interdisciplinary care to ensure an adequate quality of life.

Evaluation and treatment of constipation in infants and children: recommendations of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition

Constipation, defined as a delay or difficulty in defecation, present for 2 or more weeks, is a common pediatric problem encountered by both primary and specialty medical providers. The Constipation Guideline Committee of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) has formulated a clinical practice guideline for the management of pediatric constipation. The Constipation Guideline Committee, consisting of two primary care pediatricians, a clinical epidemiologist, and pediatric gastroenterologists, based its recommendations on an integration of a comprehensive and systematic review of the medical literature combined with expert opinion. Consensus was achieved through Nominal Group Technique, a structured quantitative method. The Committee developed two algorithms to assist with medical management, one for older infants and children and the second for infants less than 1 year of age. The guideline provides recommendations for management by the primary care provider, including evaluation, initial treatment, follow-up management, and indications for consultation by a specialist. The Constipation Guideline Committee also provided recommendations for management by the pediatric gastroenterologist.