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

Sexual function and lower urinary tract symptoms after minimally invasive endorectal pull-through in adolescent males with Hirschsprung disease

BACKGROUND

Effects of colorectal resection on sexual function and the lower urinary tract are inadequately studied in patients with Hirschsprung disease (HD). This study aimed to increase existing knowledge on sexual function and lower urinary tract symptoms (LUTS) in HD male adolescents operated with minimally invasive endorectal pull-through (ERPT).

METHODS

Non-syndromic male adolescents (12-18 years) operated with ERPT were invited to participate in this single-center cross-sectional study which included a semi-structured interview on sexual function and LUTS, a questionnaire recording LUTS, and a urodynamic study. Uroflowmetry curves were eligible for evaluation if the voided volume was >50% of expected bladder capacity. Ethical approval and informed consent were obtained.

RESULTS

Of 37 eligible male adolescents, 35 (95%) with a median age of 14.9 (12.0 -18.3) years were included. 94% had rectosigmoid aganglionosis, and 97% underwent a minimally invasive ERPT. 34 (97%) visited the outpatient clinic. The ability to get erections and to ejaculate was assessed in 25/35 (71%) adolescents. 25/25 (100%) could get an erection, and of adolescents ≥15 years 14/15 (93%) could ejaculate. 32 (91%) returned the questionnaire and underwent urodynamic studies. 15/32 (47%) reported LUTS, but most had only sporadic LUTS. 31/32 (97%) were highly satisfied with their bladder function. Sporadic urinary incontinence was reported by 4/32 (13%), but none reported social problems due to this. Of the eligible 28/32 (88%) uroflowmetry curves, 15/28 (54%) were normal.

CONCLUSIONS

Minimally invasive ERPT seems to preserve sexual function and does not induce lower urinary tract symptoms in adolescent HD males.

LEVEL OF EVIDENCE

III.

Post-operative colonic manometry in children with Hirschsprung disease: A systematic review

BACKGROUND

A significant proportion of children experience bowel dysfunction (including constipation and fecal incontinence) following surgical repair of Hirschsprung disease (HD). Persistent symptoms are thought to relate to underlying colonic and/or anorectal dysmotility. Manometry may be used to investigate the gastrointestinal motility patterns of this population.

PURPOSE

To (1) evaluate the colonic manometry equipment and protocols used in the assessment of the post-operative HD population and (2) summarize the available evidence regarding colonic motility patterns in children with HD following surgical repair.

DATA SOURCES

We performed a systematic review of the Cochrane Library, Embase, MEDLINE, and PubMed databases (January 1, 1980 and March 9, 2020). Data were extracted independently by two authors.

STUDY SELECTION

This systematic review was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Studies reporting the post-operative assessment of children with HD using colonic manometry were considered for inclusion.

RESULTS

Five studies satisfied selection criteria, providing a combined total of 496 children. Of these, 184 children with repaired HD underwent colonic manometry. Studies assessed heterogeneous populations, utilized variable manometry equipment and protocols, and reported limited baseline symptom characteristics, thus restricting comparability. All studies used low-resolution colonic manometry.

CONCLUSIONS

This systematic review highlighted the paucity of evidence informing the understanding of colonic dysmotility in the post-operative HD cohort. Current literature is limited by variable methodologies, heterogeneous cohorts, and the lack of high-resolution manometry.

Long-term outcomes of laparoscope-assisted heart-shaped anastomosis for children with hirschsprung disease: A 10-year review study

BACKGROUND AND OBJECTIVE

Several operating procedures have been reported for treating Hirschsprung Disease (HD), but the incidence of postoperative complications remains at a high level affecting both the patients' prognosis and postoperative life quality. Heart-shaped anastomosis as a novel surgery method for children with HD has been improved by our medical center. This new surgery method is characterized by a heart-shaped colorectal anastomosis after splitting the posterior rectum wall to 0.5 cm above the dentate line. The aim of this review was to research the outcomes and quality of life of laparoscope-assisted heart-shaped anastomosis (LHSA) for children with HD by comparing it with a more generally applied surgery method, the laparoscope-assisted Soave procedure (LSP).

METHODS

A retrospective review was conducted for 198 patients who underwent operations from January 2005 to December 2014 in our institution, who were divided into 97 cases of the LHSA group and 101 cases of LSP group according to the treatment methods; all the outcomes and individual quality of life data were assessed and compared.

RESULT

All the enrolled 198 children diagnosed with HD, LHSA and LSP had been successfully completed in all cases. For complications, the incidence of constipation and soiling in the LHSA group was lower than the LSP group (P = 0.030, P = 0.042 respectively). On aspects of quality of life after operation, the individual quality of life of children with fecal incontinence was scored; and the higher the scores, the better the quality of life. Patients in the LHSA group had higher scores in terms of soiling, unhappy or anxious and peer rejection than the LSP group (P = 0.003, P = 0.009, P = 0.021, respectively). Other surgical characteristics and outcomes did not significantly differ between the two groups.

CONCLUSION

LHSA is a feasible and safe minimally invasive surgery method with good long-term follow-up outcomes for HD patients. Compared with LSP, LHSA has advantages of low incidence of constipation and soiling, and provides better quality of life. Therefore, LHSA may provide a better choice for HD patients.

LEVELS OF EVIDENCE

The type of study was Clinical Research Paper and the level of evidence was level III.

Long-term Outcomes of Patients Surgically Treated for Hirschsprung Disease

Background

The only curative treatment for Hirschsprung disease (HD) is surgical repair. However, some patients experience poor postoperative outcomes. We determined long-term outcomes of all HD patients in Ontario, Canada’s most populous province.

Methods

We conducted a retrospective cohort study including all children with HD born between April 1, 1991 and March 31, 2014 in Ontario using linked health administrative data. Each HD case was matched to five non-HD controls on sex, date of birth, region of residence and income and followed to March 31, 2016. Chronic diarrhea and constipation were identified using combinations of outpatient physician billing codes in both HD patients and non-HD residents of the province. We determined risk factors associated with diarrhea and constipation, including surgery type and sociodemographic characteristics, using multivariable conditional logistic regression, and reported adjusted odds ratios (aORs).

Results

There were 3,265,172 children born in the study period, of whom 673 had HD. Compared to controls, chronic constipation was more common in HD patients (27.5% versus 2.1%; aOR 17.2, 95% CI 12.6 to 23.4), as was chronic diarrhea (29.9% versus 6.9%, aOR 5.22, 95% CI 4.19 to 6.50). In HD patients, older age at surgery was associated with increased risk of chronic constipation (OR 2.71, 95% CI 1.75 to 4.20). Surgery type, sex, rural/urban residence and income were not associated with risk of chronic constipation or diarrhea.

Conclusion

Chronic constipation and diarrhea were common following surgery for HD. Older age at surgery was associated with subsequent risk of chronic constipation. Surgery type was not associated with increased risk of chronic constipation or diarrhea.

Infra-anastomotic Innervation of Residual Aganglionic Distal Rectum After Pull-through Surgery for Hirschsprung Disease

BACKGROUND

Descending neurons are important for intestinal reflex activities, including the recto-anal inhibitory reflex involved in normal defecation. Pull-through surgery for Hirschsprung disease results in the anastomosis of ganglionic bowel to native aganglionic rectum just superior to the internal anal sphincter, which potentially could allow for physiologically significant infra-anastomotic innervation.

METHODS

The density and distribution of intramuscular neuronal nitric oxide synthase (nNOS)- and mucosal calretinin-immunoreactive nerves were evaluated proximal and distal to the anastomosis in redo resection specimens after pull-through surgery for Hirschsprung disease. The findings were compared with data collected from cadaveric controls with no history of dysmotility and the distal aganglionic segments of primary rectal resections from patients with Hirschsprung disease.

RESULTS

Native aganglionic rectum of Hirschsprung patients lacks the normal lush intramuscular nNOS- and mucosal calretinin-immunoreactive nerves present in normal bowel. In post-pull-through resection specimens obtained more than 7 months after pull-through surgery, nNOS- and calretinin-positive innervation is at least partially restored for variable distances up to 10 to 12 mm inferior to the anastomosis, respectively.

CONCLUSIONS

Innervation of infra-anastomotic muscularis propria and mucosa in the aganglionic distal rectum occurs to a variable degree after pull-through surgery for Hirschsprung disease and may contribute to individual differences in postoperative obstructive symptoms. Strategies to enhance infra-anastomotic innervation may improve clinical outcome.

The long-term quality of life outcomes in adolescents with Hirschsprung disease

BACKGROUND

Postoperative outcomes for Hirschsprung disease (HD) remain variable, with many patients affected by constipation and/or fecal incontinence. The long-term impact upon quality of life (QoL) for HD patients is unclear. We measured long-term QoL outcomes in adolescents with HD using validated questionnaires.

METHODS

Patients with HD, managed at a large tertiary pediatric institution between 1997 and 2004, were identified. Patients and/or their proxy completed validated questionnaires. Results were compared with published healthy population controls. Two questionnaires assessed QoL: Pediatric Quality of Life Inventory (PedsQL) and Fecal Incontinence and Constipation Quality of Life (FICQOL). Three measures assessed functional outcomes: Baylor Continence Scale, Cleveland Clinic Constipation Scoring System, and Vancouver Dysfunctional Elimination Symptom Survey.

RESULTS

Interviews were completed for 58 (70% response rate) patients [M:F, 49:9; median age, 14.5 years (11.1-18.7)]. No significant differences were found in general QoL scores between patients and healthy controls (84.84 versus 81.49, p = 0.28). Disease-specific questionnaires revealed reduced QoL in patients and families, with 17% of parents reporting the bowel dysfunction stopped their child from socializing and 47% of parents experiencing some degree of anxiety/depression regarding their child's bowel condition. Fecal incontinence (r = -0.59, p < 0.01), constipation (r = -0.36, p = 0.01), and dysfunctional elimination (r = -0.59, p < 0.01) all negatively correlated with QoL scores.

CONCLUSIONS

In this study, generic QoL in the adolescent HD population was comparable to healthy populations. However, children with HD have ongoing bowel dysfunction which negatively impacts upon their QoL.

LEVEL OF EVIDENCE

Prognosis study:- level II (prospective cohort study).

Prevalence, Risk Factors, and Prognosis of Postoperative Complications after Surgery for Hirschsprung Disease

BACKGROUND

Although most of patients do well after surgery for Hirschsprung disease (HSCR), there are complications in some instances that impact social aspects and quality of life. The aim of this study was to explore the prevalence, risk factors, and prognosis of these complications, providing guidance for surgeons and healthcare personnel.

METHODS

A cohort of patients (N = 229) was retrospectively reviewed in the aftermath of surgery for HSCR. All medical data and operative notes were assessed. Early and late postoperative complications were solicited by questionnaire, using logistic regression and the Cox proportional hazards regression model for analysis.

RESULTS

A total of 181 patients qualified for the study. Enterocolitis and soiling/incontinence constituted the most frequent complications, whether early or late in the postoperative period. Risk factors for developing enterocolitis included low weight, low-level IgA, preoperative enterocolitis, and lengthy aganglionic segment in the early term; whereas preoperative enterocolitis and diet control impacted complications emerging later. Risk factors in early soiling/incontinence were low weight, operative age of < 2 months, low IgA level, and lengthy aganglionic segment. Lengthy aganglionic segment, operative age of < 2 months, and toilet training were factors long-term. Prognostic factors included diet control and toilet training.

CONCLUSION

Enterocolitis and soiling/incontinence remain the most frequent complications after surgery for HSCR. Risk factors in early and late postoperative periods differed, with diet control and toilet training contributing favorably to enterocolitis and soiling/incontinence, respectively.

Changes in cholinergic and nitrergic systems of defunctionalized colons after colostomy in rabbits

BACKGROUND

This study was designed to assess smooth muscle function and motility in defunctionalized colonic segments and subsequent changes in pathways responsible for gastrointestinal motility.

METHODS

Two-month-old New Zealand rabbits were randomly allocated into control and study groups. Sigmoid colostomies were performed in the study group. After a 2-month waiting period, colonic segments were harvested in both groups. For the in vitro experiment, the isolated circular muscle strips which were prepared from the harvested distal colon were used. First, contraction responses were detected using KCl and carbachol; relaxation responses were detected using papaverine, sodium nitroprusside, sildenafil, and l-arginine. The neurologic responses of muscle strips to electrical field stimulation (EFS) were evaluated in an environment with guanethidine and indomethacin. EFS studies were then repeated with atropine, Nω-nitro-l-arginine methyl ester, atropine, and Nω-nitro-l-arginine methyl ester-added environments.

RESULTS

Although macroscopic atrophy had developed in the distal colonic segment of the colostomy, the contraction and relaxation capacity of the smooth muscle did not change. EFS-induced nitrergic-peptidergic, cholinergic-peptidergic, and noncholinergic nonnitrergic responses significantly decreased at all frequencies (0.5-32 Hz) in the study group compared with those in the control group (P < 0.05).

CONCLUSIONS

Although the contraction capacity of the smooth muscle was not affected, the motility of the distal colon deteriorated owing to the defective secretion of presynaptic neurotransmitters such as acetylcholine, nitric oxide, and neuropeptides.

Urological and sexual outcome in patients with Hirschsprung disease: A systematic review

PURPOSE

There is a paucity of recent evidence regarding long-term urological and sexual outcomes following surgery for Hirschsprung disease (HD). We aimed to undertake a systematic review of all HD literature to define these outcomes.

MATERIALS AND METHODS

A systematic literature search was conducted on studies from 1966 to 2014. Relevant articles were assessed for urological/sexual operative complications and functional sequelae. Studies were analysed in qualitative (Rangel score) and quantitative syntheses.

RESULTS

Initially 257 reports were assessed, with 24 studies were eligible for inclusion (1972-2014). Mean study quality was 16.5 ± SD 4.8 (range 6-23), indicating overall fair/poor quality. Ten studies (1021 patients) reported operative complications, with ureteric/urethral/vaginal injury occurring in seven (0.7%) patients. In three studies, the primary outcome was urological functional assessment. From 17 studies, 52/2546 patients (2.0%) had reported urinary incontinence. In infants, absent spontaneous erections post-operatively was reported in 3/203 patients (1.5%, 5 studies); of these 3, parents did not note spontaneous erections pre-operatively either. In older patients, erectile dysfunction occurred in 6/498 (1.2%) males. Other sexual outcomes were reported in 10 studies, with 5/10 studies (416 patients) reporting no erectile dysfunction. In the other studies reports ranged from non-specified sexual dysfunction in one study to diverse sexual related problems in nine (7.8%) of their patients in another.

CONCLUSIONS

Urological/sexual outcomes are rarely reported after HD surgery (24 studies over 42 years). Study quality is usually poor and a large proportion of the studies are more than 30 years old. In the majority of series it is unclear whether urological and sexual function impairments were not present or if they were not assessed. Prospective reporting of urological/sexual outcome is required, in particular in the era of new surgical techniques/approaches to HD.

Nuclear transit study in children with chronic faecal soiling after Hirschsprung disease (HSCR) surgery has revealed a group with rapid proximal colonic treatment and possible adverse reactions to food

BACKGROUND/PURPOSE

Long-term problems with faecal incontinence occur in up to 50 % of patients after pull-through for Hirschsprung disease (HSCR). The cause often remains unknown, leading to empirical treatments. Using nuclear transit study, we found some patients surprisingly had rapid proximal colonic transit, suspicious of occult diarrhoea. We aimed to assess whether these patients had unrecognized adverse reactions to food.

METHODS

Patients (n = 10, all males, 9.6 year; 4.25-15.5 years) with persistent faecal incontinence following pull-through for HSCR referred to the senior author and after exclusion of anatomical defects, underwent nuclear transit studies. Most (8) subsequently underwent breath hydrogen tests for sugar malabsorption and were tested for adverse reactions to food. Exclusion diets for protein allergens, lactose or fructose were then trialed.

RESULTS

Of the 10 patients with rapid intestinal transit proven on nuclear transit study, breath hydrogen tests for fructose and/or lactose malabsorption were done in 8, and were positive in 7/8 patients. Exclusion diets contributed to either resolution or improvement in faecal incontinence in 9/10 patients.

CONCLUSIONS

Rapid transit in the proximal, ganglionated colon may be present in children with faecal incontinence following pull-through for HSCR, possibly secondary to adverse reactions to food. This study suggests that children with post-operative soiling may benefit from a transit study and hydrogen breath tests to diagnose adverse reactions to food caused by sugar malabsorption.

Long-term results of transanal pull-through for Hirschsprung's disease: a meta-analysis

INTRODUCTION

Several operative techniques have been developed for the treatment of Hirschsprung's disease (HD) in the past decades. Since one-stage transanal pull-through (TAPT) was first performed in 1998, multiple studies have shown favourable short-and midterm results compared to other techniques with shorter operation length, shorter hospital stay and lower complication rates. The aim of this meta-analysis was to determine the longterm results following TAPT for HD.

METHODS

A systematic literature search for relevant articles was performed in four databases using the following terms "Hirschsprung/Hirschsprung's disease", "aganglionosis", "transanal", "pullthrough/pull-through", "longterm/long-term" "results", "follow-up" and "outcome". A meta-analysis was conducted for relevant articles for one-stage transanal pull-through for HD with a minimal follow-up of median 36 months regarding constipation, incontinence/soiling, enterocolitis and secondary operations. Odds ratio (OR) with 95 % confidence intervals (CI) were calculated.

RESULTS

Six studies with 316 patients matched the set criteria and were included in this analysis. Overall 45 (14.2 %) patients had disturbances of bowel function (OR 0.05, 95 % CI 0.03-0.07, p < 0.00001). Of these, 24 (53.3 %) patients experienced constipation, 8 (17.8 %) incontinence/soiling and 13 (28.9 %) enterocolitis. 10 (3.2 %) patients developed complications requiring secondary surgery. Most patients had a daily defecation frequency of 1-3 bowel movements 3 years postoperatively, resembling the stooling patterns of healthy controls.

CONCLUSION

Nearly 15 % of all patients operated with TAPT for HD continue to experience persistent bowel symptoms with constipation as the main problem. Further studies on the long-term outcome of children operated with this technique for HD are necessary to evaluate stooling patterns, urinary and sexual function as well as general quality of life during adolescence and adulthood.

Laparoscopy-assisted versus transabdominal reoperation in Hirschprung's disease for residual aganglionosis and transition zone pathology after transanal pull-through

INTRODUCTION

This study aims to describe laparoscopic reoperation (LSR) and compare its outcomes with transabdominal reoperation (TAR) for treating Hirschsprung's disease (HD).

PATIENTS AND METHODS

Eighteen patients with HD underwent reoperation for recurring constipation due to residual aganglionosis and transition zone pathology after an initial transanal procedure (LSR, n=10; TAR, n=8). Preoperative, operative and postoperative data were collected through patient follow-ups ranging from 13 to 75months to compare operative characteristics and postoperative outcomes between the two groups.

RESULTS

Ten patients underwent laparoscopic reoperation in our institution without major complications. On average, blood loss was significantly lower in the LSR group (mean±standard deviation, 83±32.7mL) than in the TAR group (185±69mL) (P=0.001). The LSR group had a shorter hospitalization time (12±2days) than the TAR group (15±2.1days) (P=0.02). There was no statistically significant difference in incidence of postoperative complications between the two groups.

CONCLUSIONS

LSR is safe and technically feasible in HD for recurring constipation due to residual aganglionosis and transition zone pathology, when initial transanal procedure fails. Although RA and TZP can be cured by reoperation, great efforts should be made to diminish the necessity of reoperation.

A population-based, complete follow-up of 146 consecutive patients after transanal mucosectomy for Hirschsprung disease

OBJECTIVE

The objective of the study is to define the population-based bowel functional outcomes and enterocolitis following transanal endorectal pull-through (TEPT) in patients with Hirschsprung disease (HD) treated at our institution between 1986 and 2011.

METHODS

146 consecutive patients who had undergone primary surgical treatment for HD were included. The median follow-up time was 15 (3-33) years. The clinical details and prevalence of enterocolitis were evaluated in all patients, and bowel function in patients >3 years of age with functional intestino-anal continuity.

RESULTS

No patients were lost to follow-up. Overall survival was 98%. The level of disease was rectosigmoid in 83%, long segment in 7%, total colonic in 4%, and extending up to the small bowel in 6%. 29% had an associated syndrome. 22% had a preoperative stoma. Operations included TEPT (89%), proctocolectomy with ileoanal anastomosis in 9%, and 3% had a permanent endostomy owing to small intestinal aganglionosis. One patient underwent intestinal transplantation. At the latest follow-up, 42% had occasional soiling, 12% had frequent soiling and 46% had no soiling. Constipation occurred in 9%. An associated syndrome was the only predictor for soiling or constipation (OR 4.3, 95% CI 1.5-12). 44% developed recurrent postoperative enterocolitis, which was predicted by extended aganglionosis (OR 6.9, 95% CI 2.4-20) and syndromatic disease (OR 2.4, 95% CI 1.2-5.0).

CONCLUSION

The major functional sequelae following TEPT were recurrent enterocolitis and fecal soiling, which was mostly occasional. An associated syndrome was a predictor of a reduced bowel functional outcome, and alongside extended aganglionosis were significant risk factors for recurrent postoperative enterocolitis.

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.

Reoperative surgery for Hirschsprung disease

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

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.

Primary transanal Swenson pull-through operation for Hirschsprung's disease

OBJECTIVE

The authors describe an experience with a newly developed technique for the treatment of Hirschsprung's disease (HD)-transanal Swenson pull-through operation (TSPT).

METHODS

The records of 27 children (15 males and 12 females) with HD proven on the basis of rectal biopsy or barium enema who underwent primary TSPT between November 2003 and April 2008 were retrospectively reviewed. Rectosigmoidectomy begins at the level just above dentate line in neonates and approximately 1-cm above dentate line in older children. The full-thickness dissection is performed upward around the rectum. The colon is transected above transition zone and anastomosed to the anus. All patients had postoperative pathologic proof. Data are expressed as mean and SD.

RESULTS

Mean age at operation was 29.4 +/- 48.2 months (range, 1-155 months). The operative time averaged 153.5 +/- 85.9 min (range, 65-400 min). There was a statistically significant difference between those younger than 1 month (107.1 +/- 14.8 months) and those greater than 1 month (190.7 +/- 101.1 months). None did receive blood transfusion. Average length of hospital stay was 9.1 +/- 4.1 days (range, 4-21 days). Peri- and postoperative complications included anastomotic stricture (n = 6), enterocolitis (n = 3), and urethral injury (n = 1). Fecal continence (stooling frequency rate of 1-2 times per day) was noted in 70.8% (17/24) and 77.8% (14/18) at 1- and 2-year follow-up, respectively. There was no mortality in the series.

CONCLUSIONS

Primary TSPT would be an alternative, safe technique in children with HD. The technique is not difficult, and associated with acceptable short-term outcomes. A long-term follow-up will be necessary to assess the real benefit of the technique.

Disturbances of colonic motility in mouse models of Hirschsprung's disease

Mutations in genes encoding members of the GDNF and endothelin-3 (Et-3) signaling pathways can cause Hirschsprung's disease, a congenital condition associated with an absence of enteric neurons in the distal gut. GDNF signals through Ret, a receptor tyrosine kinase, and Et-3 signals through endothelin receptor B (Ednrb). The effects of Gdnf, Ret, and ET-3 haploinsufficiency and a null mutation in ET-3 on spontaneous motility patterns in adult and developing mice were investigated. Video recordings were used to construct spatiotemporal maps of spontaneous contractile patterns in colon from postnatal and adult mice in vitro. In Ret(+/-) and ET-3(+/-) mice, which have normal numbers of enteric neurons, colonic migrating motor complexes (CMMCs) displayed similar properties under control conditions and following inhibition of nitric oxide synthase (NOS) activity to wild-type mice. In the colon of Gdnf(+/-) mice and in the ganglionic region of ET-3(-/-) mice, there was a 50-60% reduction in myenteric neuron number. In Gdnf(+/-) mice, CMMCs were present, but abnormal, and the proportion of myenteric neurons containing NOS was not different from that of wild-type mice. In the ganglionic region of postnatal ET-3(-/-) mice, CMMCs were absent, and the proportion of myenteric neurons containing NOS was over 100% higher than in wild-type mice. Thus impairments in spontaneous motility patterns in the colon of Gdnf(+/-) mice and in the ganglionic region of ET-3(-/-) mice are correlated with a reduction in myenteric neuron density.