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

Assessing fecal load with ultrasound in children with colorectal pathology: ReKiSo study

PURPOSE

To evaluate bowel management for children with colorectal pathology by measuring transverse rectal diameter (TRD) and assessing fecal load with transabdominal rectal ultrasound (TRU).

METHODS

Prospective case-control study of children receiving bowel management (BM) between 04/2023 and 04/2024 was done. There was inclusion of patients with Hirschsprung disease (HD), anorectal malformation (ARM) and functional constipation (FC). Patients with other congenital or neurological conditions were excluded. Control group consisted of inpatients and outpatients without abdominal complaints. FC was diagnosed according to ROM-IV-criteria. For HD and ARM, we followed a list of symptoms. To assess fecal load, we visualized the TRD using the Klijn (Klijn et al. in J Urol 172:1986-1988, 2004) method. The bladder was moderately full. The fecal load was assessed retrograde from the rectum. Follow-up was at 1/3/6 months. Secondary data were collected from medical records. Sample size calculated a priori and follow-up group with new gathered data.

RESULTS

p value for TRD in all groups significant with p < 0.05 and in grouped follow-up.

CONCLUSION

Ultrasound is a useful tool for assessing fecal load and helps diagnose constipation and monitor BM. Irrespective of colorectal pathology, a cut-off of 3 cm seems to discriminate between children without constipation/overload symptoms and asymptomatic patients. We present a radiation-free method for monitoring bowel management.

Are the complications after laparo-assisted endo-rectal pull-through for Hirschsprung disease related to the change of the anal tone?

The main advantage of the laparo-assisted transanal endorectal pull-through technique (LA - TERPT) for Hirschsprung Disease (HD) is the respect to the rectal-anal anatomy. Postoperative complications have been observed recently. The present study aims to determine how often these postoperative complications occur in these patients. From January 2009 to December 2018, a retrospective analysis was conducted on 36 children (25 males) with HD who underwent LA-TERPT. Data were collected on the age of diagnosis and surgery, sex, the presence of other pathologies, and cases of enterocolitis. In all cases, anorectal manometry (ARM) was performed to evaluate the anal tone. The median age at diagnosis was 2 months and the mean age at surgery was 5 months. Nine related pathologies were identified: five cases of Down syndrome, one case of hypertrophic stenosis of the pylorus, atresia of the esophagus, polydactyly, and anorectal malformation. A patient with total colonic aganglionosis was identified through laparoscopic serummuscular biopsies. Enterocolitis was diagnosed in 7 cases before and 6 after surgery. At follow-up, the complications recorded were: 5 cases of constipation (treated with fecal softeners), one case of anal stenosis (patient with anorectal malformation), 16 cases of soiling (treated with enemas) and 1 child with fecal incontinence (treated with a transanal irrigation system). The ARM was performed in all 36 cases and showed normal anal tone, except for one case with anal hypotonia. LA-TERPT is an important surgical technique for HD. According to the literature, soiling is the most main complication after HD surgery, probably due to "pseudo-incontinence" with normal anal sphincter tone.

Hirschsprung's disease. Management

BACKGROUND

Hirschsprung's disease (HD) is a rare congenital disease that is characterised by the absence of ganglion cells in the myenteric plexus starting in the distal bowel. This results in distal functional obstruction and may lead to complications like enterocolitis. The treatment is surgical and requires the resection of the aganglionic segment, and the pull-through of normal intestine into the anal opening. However, even after successful surgery, patients may continue to have symptoms.

AIM

Discuss current surgical techniques and management strategies for patients with postoperative symptoms after surgical correction of Hirschsprung's disease.

METHODS

A review of the literature was done through PubMed, with a focus on clinical management and approach.

RESULTS

We describe the clinical problems that can occur after surgical correction. These include obstructive symptoms, enterocolitis, or faecal incontinence. A systematic approach for the evaluation of these patients includes the exclusion of anatomic, inflammatory, behavioural or motility related factors. Depending on the severity of the symptoms, the evaluation includes examination under anaesthesia, the performance of contrast studies, endoscopic studies, measurement of anal sphincter function and colonic motility studies. The treatment is focused towards addressing the different pathophysiological mechanisms, and may include medical management, botulinum toxin to the anal sphincter or rarely redo-operation.

CONCLUSIONS

Patients with Hirschsprung's disease need to have surgical correction, and their postoperative long-term management is complex given a variety of associated problems that can occur after surgery. A systematic evaluation is necessary to provide appropriate therapy.

Short and Long-Term Outcomes in Hirschsprung Disease: Are the Syndrome-Associated Patients Really Doing Worse?

INTRODUCTION

Given the lack of data to help caregivers in the follow-up of Hirschsprung disease (HD), this study aimed to compare the functional outcomes of isolated Hirschsprung disease (I-HD) to syndrome-associated Hirschsprung disease (SA-HD) at 1, 3, 5, and 10 years.

METHODS

A retrospective chart review of patients diagnosed with HD between January 1990 and May 2021 at our pediatric center was performed to collect data on patient characteristics, investigations, and treatments. Ninety-five patients were identified, of whom 76 were included in the study. SA-HD is defined as a syndrome known to be associated with HD or cognitive impairment.

RESULTS

Patient characteristics were comparable between groups ( P > 0.05). There were 52 patients with I-HD and 24 with SA-HD. The patients median age was 9 days at diagnosis and 1.5 month at surgery. SA-HD patients became bowel continent at a significantly older age (mean age 8.43 vs 4.94 years, P = 0.0471) and received more bowel continence medications. At 5 years, SA-HD patients requiring ≥2 medications for bowel continence represented 54.5% versus 11.1% of I-HD patients ( P = 0.009). Lastly, SA-HD patients had urinary incontinence at a significantly older age ( P = 0.0136, 5 years).

CONCLUSION

Clinicians should be aware that SA-HD patients are more prone to bladder dysfunction and became bowel continent at an older age than I-HD patients. They need more and prolonged bowel management medications, and other important complications need to be addressed in patient care. These results should prompt a longer follow-up period for these patients, especially in SA-HD.

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

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

Abnormal enteric nervous system and motor activity in the ganglionic proximal bowel of Hirschsprung's disease

Hirschsprung's disease (HSCR) is a congenital defect in which the enteric nervous system (ENS) does not develop in the distal bowel, requiring surgical removal of the portions of bowel without ENS ganglia ('aganglionic') and reattachment of the 'normal' proximal bowel with ENS ganglia. Unfortunately, many HSCR patients have persistent dysmotility (e.g., constipation, incontinence) and enterocolitis after surgery, suggesting that the remaining bowel is not normal despite having ENS ganglia. Anatomical and neurochemical alterations have been observed in the ENS-innervated proximal bowel from HSCR patients and mice, but no studies have recorded ENS activity to define the circuit mechanisms underlying post-surgical HSCR dysfunction. Here, we generated a HSCR mouse model with a genetically-encoded calcium indicator to map the ENS connectome in the proximal colon. We identified abnormal spontaneous and synaptic ENS activity in proximal colons from GCaMP-Ednrb ^-/- mice with HSCR that corresponded to motor dysfunction. Many HSCR-associated defects were also observed in GCaMP-Ednrb ^+/- mice, despite complete ENS innervation. Results suggest that functional abnormalities in the ENS-innervated bowel contribute to post-surgical bowel complications in HSCR patients, and HSCR-related mutations that do not cause aganglionosis may cause chronic colon dysfunction in patients without a HSCR diagnosis.

Stem cell-based therapy for hirschsprung disease, do we have the guts to treat?

Hirschsprung disease (HSCR) is a congenital anomaly of the colon that results from failure of enteric nervous system formation, leading to a constricted dysfunctional segment of the colon with variable lengths, and necessitating surgical intervention. The underlying pathophysiology includes a defect in neural crest cells migration, proliferation and differentiation, which are partially explained by identified genetic and epigenetic alterations. Despite the high success rate of the curative surgeries, they are associated with significant adverse outcomes such as enterocolitis, fecal soiling, and chronic constipation. In addition, some patients suffer from extensive lethal variants of the disease, all of which justify the need for an alternative cure. During the last 5 years, there has been considerable progress in HSCR stem cell-based therapy research. However, many major issues remain unsolved. This review will provide concise background information on HSCR, outline the future approaches of stem cell-based HSCR therapy, review recent key publications, discuss technical and ethical challenges the field faces prior to clinical translation, and tackle such challenges by proposing solutions and evaluating existing approaches to progress further.

The impact of botulinum injection for hospitalized children with Hirschsprung-associated enterocolitis

INTRODUCTION

Stasis from obstruction at the level of the internal anal sphincter (IAS) can lead to Hirschsprung-associated enterocolitis (HAEC) and may be improved by botulinum toxin (BT) injections. Our aim was to determine if BT injection during HAEC episodes decreased the number of recurrent HAEC episodes and/or increased the interval between readmissions.

METHODS

A retrospective review was performed of patients admitted for HAEC from January 2010 to December 2019. Demographics and outcomes of patients who received BT were compared to patients who did not receive BT during their hospital stay.

RESULTS

A total of 120 episodes of HAEC occurred in 40 patients; 30 patients (75%) were male, 7 (18%) had Trisomy 21 and 10 (25%) had long-segment disease. On multivariate analysis, patients who received BT during their inpatient HAEC episode had a longer median time between readmissions (p = 0.04) and trending toward an association with fewer readmissions prior to a follow-up clinic visit (p = 0.08).

CONCLUSION

The use of BT in HD patients hospitalized for HAEC is associated with an increased time between recurrent HAEC episodes and trended toward fewer recurrent episodes. The use of BT should be considered in the management of patients admitted with HAEC.

Outpatient Botulinum Injections for Early Obstructive Symptoms in Patients with Hirschsprung Disease

INTRODUCTION

Botulinum toxin (BT) injections may play a role in preventing Hirschsprung associated enterocolitis (HAEC) episodes related to internal anal sphincter (IAS dysfunction). Our aim was to determine the association of outpatient BT injections for early obstructive symptoms on the development of HAEC.

METHODS

A retrospective review of children who underwent definitive surgery for Hirschsprung disease (HSCR) from July 2010 - July 2020 was performed. The timing from pull-through to first HAEC episode and to first BT injection was recorded. Primary analysis focused on the rate of HAEC episodes and timing between episodes in patients who did and did not receive BT injections.

RESULTS

Eighty patients were included. Sixty patients (75%) were male, 15 (19%) were diagnosed with trisomy 21, and 58 (72.5%) had short-segment disease. The median time to pull-through was 150 days (IQR 16, 132). Eight patients (10%) had neither an episode of HAEC or BT injections and were not included in further analysis. Forty-six patients (64%) experienced at least one episode of HAEC, while 64 patients (89%) had at least one outpatient BT injection. Compared to patients who never received BT injections (n = 9) and those who developed HAEC prior to BT injections (n = 35), significantly fewer patients who received BT injections first (n = 28) developed enterocolitis (P < 0.001), with no patient developing more than one HAEC episode.

CONCLUSION

Outpatient BT is associated with decreased episodes of HAEC and increased interval between HAEC episodes requiring inpatient treatment. Scheduling outpatient BT injections to manage obstructive symptoms may be beneficial after pull-through for HSCR.

Clinical predictors of readmission after surgery for Hirschsprung disease

The reasons for readmission of children with Hirschsprung disease (HD) are multiple. The study aims to predict the relevant factors for the readmission of children with HD by collecting and analyzing the relevant data of the child's admission to the hospital at the time of surgery.A retrospective review was performed including all patients with surgical treatment of HD at our institution between the years of 2011 to 2020. Univariate and multivariate Logistic regression analysis were performed to obtain the independent risk factor for this study. The receiver operating characteristic curve (ROC) were used to assess the performance of derived models.A total of 162 patients were identified. The average presurgery weights were 6.93 ± 1.78 kg in the readmission group and 8.38 ± 3.17 kg in the non-readmission group. Six children were classified as a low-weight in the readmission group, and 11 children classified as low-weight in the non-readmission group. The length of the intestinal tube after resection was 25.25 ± 15.21 cm in the readmission group, and 16.23 ± 4.10 cm in the non-readmission group. The ROC for the prediction model of readmission after HD surgery (AUC = 0.811).In children undergoing the HD surgery, we showed preoperative low body weight and long intra-operative bowel resection significantly increase the probability of readmission due to complications.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

Level II (retrospective cohort study).

Hirschsprung's Disease-Recent Understanding of Embryonic Aspects, Etiopathogenesis and Future Treatment Avenues

Hirschsprung's disease is a neurocristopathy, caused by defective migration, proliferation, differentiation and survival of neural crest cells, leading to gut aganglionosis. It usually manifests rapidly after birth, affecting 1 in 5000 live births around the globe. In recent decades, there has been a significant improvement in the understanding of its genetics and the association with other congenital anomalies, which share the pathomechanism of improper development of the neural crest. Apart from that, several cell populations which do not originate from the neural crest, but contribute to the development of Hirschsprung's disease, have also been described, namely mast cells and interstitial cells of Cajal. From the diagnostic perspective, researchers also focused on "Variants of Hirschsprung's disease", which can mimic the clinical signs of the disease, but are in fact different entities, with distinct prognosis and treatment approaches. The treatment of Hirschsprung's disease is usually surgical resection of the aganglionic part of the intestine, however, as many as 30-50% of patients experience persisting symptoms. Considering this fact, this review article also outlines future hopes and perspectives in Hirschsprung's disease management, which has the potential to benefit from the advancements in the fields of cell-based therapy and tissue engineering.

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.

Functional outcome, quality of life, and 'failures' following pull-through surgery for hirschsprung's disease: A review of practice at a single-center

AIMS

The purpose of this study was to assess bowel function and quality of life (QoL) in patients with Hirschsprung's disease (HD) and identify patients who have 'failed' treatment.

METHODS

A review of a single-center HD cohort treated with pull-through surgery from 2004 to 2017 was completed. Bowel function of patients five years and above and QoL of all patients were assessed using validated questionnaires. Patients who 'failed' treatment were defined as above five years with one or more of: a) long-term stoma, b) needing an antegrade continence enema or transanal irrigation, c) severe soiling, or d) severe constipation. Statistical analysis was performed with P < 0.05 deemed significant. Data are given as mean [range].

RESULTS

Seventy-one patients presented with HD within the study period. Mean follow-up was 5.4 years [0.7-13.3]. Of 38 eligible patients, bowel function was assessed in 24 patients (nine had a stoma, five lost to follow-up). The mean incontinence score was 17 [0-28)], and the mean constipation score was 17 [5-25]. Incontinence and constipation scores were worse than healthy controls (P < 0.001 and P = 0.001, respectively) and did not improve with age. Fifty-six patients had QoL assessed with no difference between our cohort (81 [25-100]) and healthy controls (81 [unknown]); (P = 0.85). Thirty-three patients were assessed for 'failure' (bowel function score n = 24; stoma n = 9). Thirty of 33 (91%) children older than five years can be considered to have 'failed' treatment.

CONCLUSIONS

Patients have worse bowel function than healthy children, which does not improve with age. QoL is comparable to healthy controls. A significant proportion of patients have poor outcomes and have 'failed' treatment.

LEVEL OF EVIDENCE

Level III.

Botulinum toxin injections after surgery for Hirschsprung disease: Systematic review and meta-analysis

BACKGROUND

A large proportion of patients with Hirschsprung disease experience persistent obstructive symptoms after corrective surgery. Persistent obstructive symptoms may result in faecal stasis that can develop into Hirschsprung-associated enterocolitis, a potential life-threatening condition. Important treatment to improve faecal passage is internal anal sphincter relaxation using botulinum toxin injections.

AIM

To give an overview of all empirical evidence on the effectiveness of botulinum toxin injections in patients with Hirschsprung disease.

METHODS

A systematic review and meta-analysis was done by searching PubMed, EMBASE and the Cochrane Library, using entry terms related to: (1) Hirschsprung disease; and (2) Botulinum toxin injections. 14 studies representing 278 patients met eligibility criteria. Data that were extracted were proportion of patients with improvement of obstructive symptoms or less enterocolitis after injection, proportion of patients with adverse effects and data on type botulinum toxin, mean dose, average age at first injection and patients with associated syndromes. Random-effects meta-analysis was used to aggregate effects and random-effects meta-regression was used to test for possible confounding factors.

RESULTS

Botulinum toxin injections are effective in treating obstructive symptoms in on average 66% of patients [event rate (ER) = 0.66, P = 0.004, I² = 49.5, n = 278 patients]. Type of botulinum toxin, average dose, average age at first injections and proportion of patients with associated syndromes were not predictive for this effect. Mean 7 duration of improvement after one botulinum toxin injections was 6.4 mo and patients needed on average 2.6 procedures. There was a significant higher response rate within one month after botulinum toxin injections compared to more than one month after Botulinum toxin injections (ER = 0.79, vs ER = 0.46, Q = 19.37, P < 0.001). Botulinum toxin injections were not effective in treating enterocolitis (ER 0.58, P = 0.65, I² = 71.0, n = 52 patients). There were adverse effects in on average 17% of patients (ER = 0.17, P < 0.001, I² = 52.1, n = 187 patients), varying from temporary incontinence to mild anal pain.

CONCLUSION

Findings from this systematic review and meta-analysis indicate that botulinum toxin injections are effective in treating obstructive symptoms and that adverse effects were present, but mild and temporary.

Experience with the Redo Pull-Through for Hirschsprung's Disease

Aim:

This study aims to evaluate the need of Redo pull-through (Re PT) procedures for Hirschsprung's disease (HD) and suggest preventive strategies.

Materials and Methods:

Patients who underwent redo procedures for HD from 1980 to 2016 by a single surgeon were retrospectively reviewed.

Results:

Of 167 patients operated for HD, 32 underwent Re PT; 7 were previously operated by the same surgeon, while 25 were referred from outside. Indication for Re PT included residual disease including the rectal pouch following-Duhamel (12), false-negative biopsy (3), retraction of bowel (5), anorectal stricture (2), bowel twist (1), cuff inversion (2), postmyectomy continued symptoms after primary PT (1), fecal fistula (1), Re PT after surgery for adhesive intestinal obstruction (3), bleeding (1), and combination of causes, including scarred perineum (1). Age at follow-up ranged from 2.5 to 26 years. Proximal diversion was performed in 19 and 14 underwent open Scott Boley's/Soave PT and 5 ileoanal anastomosis. Of the remaining, nondiverted 13 patients, 5 underwent transanal endorectal PT and 8 underwent PT of colostomy.

Conclusions:

Most patients of Re PT came after an initial Duhamel's procedure. Retraction of bowel, inversion of cuff, twist, distal bowel stricture, and perianal fibrosis were found after Scott Boley procedure. Proper planning with an initial diversion, nutritional buildup, barium study evaluation, frozen section facility, experienced pathologist, and an expert surgeon are prerequisites for a successful outcome after an initial as well as Re PT.

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

BACKGROUND/PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

TYPE OF STUDY

Systematic review and meta-analysis.

LEVEL OF EVIDENCE

Level II.

The advances of genetics research on Hirschsprung's disease

Hirschsprung's disease (HSCR) is a rare and complex congenital disorder characterized by the absence of the enteric neurons in lower digestive tract with an incidence of 1/5 000. Affected infant usually suffer from severe constipation with megacolon and distended abdomen, and face long-term complications even after surgery. In the last 2 decades, great efforts and progresses have been made in understanding the genetics and molecular biological mechanisms that underlie HSCR. However, only a small fraction of the genetic risk can be explained by the identified mutations in the previously established genes. To search novel genetic alterations, new study designs with advanced technologies such as genome/exome-wide association studies (GWASs/EWASs) and next generation sequencing (NGS) on target genes or whole genome/exome, were applied to HSCR. In this review, we summaries the current development of the genetics researches on HSCR based on GWASs/EWASs and NGS, focusing on the newly discovered variants and genes, and their potential roles in HSCR pathogenesis.

Comparison of Hirschsprung-associated enterocolitis following Soave and Duhamel procedures

BACKGROUND

Hirschsprung-associated enterocolitis (HAEC) represents the primary cause of high morbidity and mortality in Hirschsprung disease (HSCR) patients. The most common surgical methods for HSCR are the Soave and Duhamel procedures. Therefore, we aimed to compare the HAEC frequency following the Soave and Duhamel procedures.

METHODS

Medical records were retrospectively analyzed for patients who underwent the Soave and Duhamel pull-through at Dr. Sardjito Hospital, Indonesia from 2010 to 2015. The diagnosis of HAEC was determined using a HAEC scoring system.

RESULTS

One hundred patients were involved (Soave: 52 males and 19 females vs. Duhamel: 23 males and 6 females, p=0.62). There was significant difference in mean age at pull-through (Soave: 29.9±45.2 vs. Duhamel: 50.8±47.5months, p=0.04), whereas mean age of HSCR diagnosis and pre-operative enterocolitis frequency did not differ significantly between groups (Soave: 25.4±41.0 vs. Duhamel: 43.7±48.1months, p=0.06, and Soave: 7% vs. Duhamel: 14%, p=0.44, respectively). The HAEC frequency after pull-through was significantly higher in the Duhamel than the Soave group (28% vs. 10%, respectively, p=0.03). Furthermore, pre-operative enterocolitis showed a significant association with HAEC following pull-through (p=2.0×10-4) and the risk of HAEC after Soave pull-through was increased in long-segment aganglionosis compared to short-segment HSCR (p=0.015).

CONCLUSIONS

The frequency of HAEC was significantly higher after the Duhamel than the Soave procedure. Moreover, patients with pre-operative enterocolitis are prone to have HAEC following pull-through.

LEVEL OF EVIDENCE

III.

Hirschsprung disease - integrating basic science and clinical medicine to improve outcomes

Hirschsprung disease is defined by the absence of enteric neurons at the end of the bowel. The enteric nervous system (ENS) is the intrinsic nervous system of the bowel and regulates most aspects of bowel function. When the ENS is missing, there are no neurally mediated propulsive motility patterns, and the bowel remains contracted, causing functional obstruction. Symptoms of Hirschsprung disease include constipation, vomiting, abdominal distension and growth failure. Untreated disease usually causes death in childhood because bloodstream bacterial infections occur in the context of bowel inflammation (enterocolitis) or bowel perforation. Current treatment is surgical resection of the bowel to remove or bypass regions where the ENS is missing, but many children have problems after surgery. Although the anatomy of Hirschsprung disease is simple, many clinical features remain enigmatic, and diagnosis and management remain challenging. For example, the age of presentation and the type of symptoms that occur vary dramatically among patients, even though every affected child has missing neurons in the distal bowel at birth. In this Review, basic science discoveries are linked to clinical manifestations of Hirschsprung disease, including partial penetrance, enterocolitis and genetics. Insights into disease mechanisms that might lead to new prevention, diagnostic and treatment strategies are described.

The impact of down-regulated SK3 expressions on Hirschsprung disease

Background

Some Hirschsprung’s disease (HSCR) patients showed persistent bowel symptoms following an appropriately performed pull-through procedure. The mechanism is presumed to be down-regulated small-conductance calcium-activated potassium channel 3 (SK3) expression in the HSCR ganglionic intestines. We aimed to investigate the SK3 expression’s impact in HSCR patients after a properly performed pull-through surgery in an Indonesian population, a genetically distinct group within Asia.

Methods

We assessed SK3 gene expression in both the ganglionic and aganglionic colon of HSCR patients and controls colon by quantitative real-time polymerase chain reaction (RT-PCR).

Results

We ascertained fourteen sporadic HSCR patients and six anorectal malformation patients as controls. Quantitative RT-PCR showed that the SK3 expression was significantly lower (23-fold) in the ganglionic colon group compared to the control group (9.9 ± 4.6 vs. 5.4 ± 3.4; p = 0.044). The expression of SK3 in the aganglionic colon group was also significantly lower (43-fold) compared to the control group (10.8 ± 4.4 vs. 5.4 ± 3.4; p = 0.015).

Conclusion

Our study shows that the down-regulated SK3 expression in ganglionic intestines might contribute to the persistent bowel symptoms following a properly performed pull-through surgery in Indonesian HSCR patients. Furthermore, this study is the first report of SK3 expression in a sample population of Asian ancestry.

Hirschsprung disease-Bowel function beyond childhood

Hirschsprung disease is a developmental defect of the enteric nervous system characterized by lack of enteric neurons in the distal hindgut. There are numerous reports on short-term outcomes indicating that impaired bowel function is common. Recently, several controlled studies show that bowel function outcomes are affected beyond childhood, in adolescents and adults, compared with healthy control subjects. Constipation and fecal incontinence are common. The impaired bowel function appears to have a negative impact on quality of life, although, a majority of patients have adapted to their symptoms. On the other hand, Hirschsprung disease seems to have limited impact on education and occupation in adult life. The aim of this review was to summarize current knowledge of bowel function outcome beyond childhood in patients with Hirschsprung disease.