Gastrointestinal transit in children with chronic idiopathic constipation

Testing in functional constipation-What's new and what works

BACKGROUND

Constipation is among the most common symptoms prompting a consultation with a paediatric gastroenterologist. While most patients will respond to lifestyle and dietary changes and conventional therapy, some may require diagnostic studies.

AIM

To review the diagnostics studies used to evaluate children with functional constipation.

MATERIALS AND METHODS

There is no evidence to support the routine use of abdominal X-rays in the evaluation of paediatric constipation. Colon transit by radiopaque markers (ROM) should be indicated when medical history does not match clinical findings, to guide colon manometry (CM) performance and to discriminate between faecal incontinence from functional constipation and non-retentive faecal incontinence. Colon scintigraphy may be useful as an alternative to ROM. Lumbar spine MRI may be indicated to evaluate for spinal abnormalities. The role of defecography has not been properly evaluated in children. Anorectal manometry in children is indicated primarily to evaluate anal resting pressure, presence and quality of the recto-anal inhibitory reflex and simulated defecation manoeuvres. The CM is indicated to guide surgical interventions after failing medical therapy.

CONCLUSIONS

The goal of these studies is to identify treatable causes of constipation. Most of these studies are designed to evaluate anatomy, transit and/or colon/rectum motility function and are primarily indicated in those who fail to respond to conventional therapy.

Gastrointestinal radionuclide imaging in pediatric age group

Pediatric gastrointestinal imaging plays a crucial role in evaluating and managing digestive system disorders in children. This comprehensive review dives into the nuances of pediatric gastrointestinal imaging techniques, focusing on three specific modalities: gastric emptying scintigraphy (GES), intestinal transit scintigraphy (ITS), and gastrointestinal bleeding scintigraphy. GES involves real-time monitoring of stomach emptying using radiotracers and gamma camera technology. While challenges exist in standardizing protocols due to age-specific meal compositions, GES remains pivotal in diagnosing motility disorders, gastroesophageal reflux, and abdominal pain in children. ITS, utilizing [67Ga], provides insights into gastrointestinal motility disorders such as Hirschsprung disease. It aids in whole-gut transit evaluation, guiding surgical interventions and improving long-term clinical outcomes. Gastrointestinal bleeding scintigraphy, employing [99mTc], assists in diagnosing conditions like Meckel's diverticulum and occult bleeding, offering continuous monitoring to pinpoint the bleeding site along the entire gastrointestinal tract. SPECT-CT improves the accuracy and the standards of care. Each technique's protocol details, clinical indications, and diagnostic capabilities are thoroughly discussed, highlighting the importance of these non-invasive, functional imaging modalities in pediatric gastroenterology.

Intrapyloric Botulinum Toxin A Injection for Gastroparesis and Functional Upper Gastrointestinal Symptoms in Children: Mayo Clinic Experience, Review of the Literature, and Meta-analysis

OBJECTIVE

We aimed to assess the efficacy of intrapyloric botulinum toxin A injection (IPBTI) in children with and without gastroparesis and to perform a meta-analysis and review of the literature.

METHODS

We retrospectively searched our electronic health records to identify children (aged < 18 years) who underwent an esophagogastroduodenoscopy with IPBTI between 2007 and 2018 for persistent upper gastrointestinal tract symptoms. We included children with and without gastroparesis and excluded children with a history of gastrointestinal surgery, gastrointestinal obstruction, or mucosal disease that could explain their symptoms. A meta-analysis including our study findings was performed.

RESULTS

We identified 20 children (mean [standard deviation] age, 9.7 [5.8] years; 14 [70%] girls) with upper gastrointestinal symptoms who underwent IPBTI at our institution during the study period. Of the 20 children, 17 (85%) underwent gastric emptying scintigraphy, only nine (53%) of whom had gastroparesis. Response to IPBTI was reported in ten children (50%). Response to IPBTI did not differ by the presence of gastroparesis in included children (p = 0.64). Repeated IPBTI was performed in four children who had a response to the first injection; all four reported no benefit from the second IPBTI. There were no reported complications of IPBTI in our cohort. The meta-analysis indicated that 68% (95% confidence interval 59-78) of patients had a response to IPBTI, regardless of the presence of gastroparesis; 66% (95% confidence interval 53-78) of patients who had gastroparesis had a response to IPBTI.

CONCLUSIONS

Intrapyloric botulinum toxin A injection is safe in children and can offer transient relief for patients with refractory upper gastrointestinal symptoms with and without gastroparesis.

Proceedings of the 2018 Advances In Motility and In NeuroGastroenterology: AIMING for the Future Single Topic Symposium

OBJECTIVES

Motility and functional disorders are common in children and often debilitating, yet these disorders remain challenging to treat effectively. At the 2018 Annual North American Society for Pediatric Gastroenterology, Hepatology and Nutrition meeting, the Neurogastroenterology and Motility Committee held a full day symposium entitled, 2018 Advances In Motility and In NeuroGastroenterology - AIMING for the future. The symposium aimed to explore clinical paradigms in pediatric gastrointestinal motility disorders and provided a foundation for advancing new scientific and therapeutic research strategies.

METHODS

The symposium brought together leading experts throughout North America to review the state of the art in the diagnosis and management of motility and functional disorders in children. Presentations were divided into esophageal, antral duodenal, and colorectal modules. Each module included oral presentations by experts in the respective fields, leading to thought-provoking discussions. There were 2 breakout sessions with small group discussions on select topics, focusing on defining scientific insights into the diagnosis and management of pediatric functional gastrointestinal and motility disorders in a systematic, segment-based approach.

CONCLUSIONS

The field of neurogastroenterology has made remarkable progress in the last decade. The current report summarizes the major learning points from the symposium highlighting the diagnosis and promising therapies on the horizon for pediatric neurogastrointestinal and motility disorders.

'Rapid transit' constipation in children: a possible genesis for irritable bowel syndrome

Children with chronic idiopathic constipation (CIC) often end up at the surgeon when medical treatments have failed. This opinion piece discusses a recently described pattern of CIC called 'Rapid transit constipation (RTC)' first identified in 2011 as part of surgical workup. RTC was identified using a nuclear medicine gastrointestinal transit study (NMGIT or nuclear transit study) to determine the site of slowing within the bowel and to inform surgical treatment. Unexpectedly, we found that RTC occured in 29% of 1000 transit studies in a retrospective audit. Irritable bowel syndrome (IBS) occurs in 7-21% of the population, with a higher prevalence in young children and with constipation type dominating in the young. While 60% improve with time, 40% continue with symptoms. First-line therapy for IBS in adults is a diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols which reduces symptoms in > 70% of patients. In children with functional gastrointestinal disorders, fructose intolerance occurs in 35-55%. Reducing fructose produced significant improvement in 77-82% of intolerant patients. In children with RTC and a positive breath test upon fructose challenge, we found that exclusion of fructose significantly improved constipation, abdominal pain, stool consistency and decreased laxative use. We hypothesise that positive breath tests and improvement of pain and bowel frequency with sugar exclusion diets in RTC suggest these children have IBS-C. These observations raise the possibility that many children with CIC could be treated by reducing fructose early in their diet and this might prevent the development of IBS in later life.

Diagnostic Tests in Pediatric Constipation

Constipation is one of the most common gastrointestinal symptoms in children. With a median reported prevalence of 12%, it accounts for about 25% of all pediatric gastroenterology consultations. The majority of children experiences functional constipation and do not usually require any diagnostic testing. For those children not responding to conventional medical treatment or in the presence of a more significant clinical picture, however, an accurate instrumental assessment is usually recommended to evaluate either the underlying pathophysiologic mechanisms or a possible organic etiology. The present review analyzes the possible diagnostic investigations for severely constipated children, focusing on their actual indications and their utility in clinical practice. During the last decade, there has been a remarkable increase in our knowledge of normal and abnormal colonic and anorectal motility in children, and a number of different techniques to measure transit and motility have been developed and are discussed in this narrative review.

Surgical Management of Idiopathic Constipation in Pediatric Patients

Constipation is a common childhood problem, but an anatomic or physiologic cause is identified in fewer than 5% of children. By definition, idiopathic constipation is a diagnosis of exclusion. Careful clinical evaluation and thoughtful use of imaging and other testing can help exclude specific causes of constipation and guide therapy. Medical management with laxatives is effective for the majority of constipated children. For those patients unresponsive to medications, however, several surgical options can be employed, including anal procedures, antegrade colonic enemas, colorectal resection, and intestinal diversion. Judicious use of these procedures in properly selected patients and based on appropriate preoperative testing can lead to excellent outcomes. This review summarizes the surgical options available for managing refractory constipation in children and provides guidance on how to choose the best procedure for a given patient.

Home-Based Transabdominal Interferential Electrical Stimulation for Six Months Improves Paediatric Slow Transit Constipation (STC)

BACKGROUND

Transcutaneous electrical stimulation (TES) for one to two months has produced some improvement in treatment-resistant slow-transit constipation (STC) in children. Optimal parameters for treatment are not known. It is possible that more improvement would occur with stimulation for longer. This study examined the effectiveness of stimulation for six months.

METHODS

Children with STC confirmed by nuclear transit study (NTS) were enrolled prospectively. All had chronic constipation for greater than two years and had failed medical treatment. TES was performed for one hour/day for six months using the INF 4160 (Fuji Dynamics) portable stimulator and 4 cm × 4 cm electrodes near the belly button and on the back. Families kept bowel diaries and completed PEDSQLCore QOL (4.0) questionnaires before and at end of treatment.

RESULTS

Sixty-two children (34 females; seven years, 2-16 year) with STC were studied. Defecation frequency increased in 57/62 (91%, mean ± SEM pre- 1.49 ± 0.20 vs. post- 3.25 ± 0.25 defecation/week, p < 0.0001) with the number with ≥3BA increasing from 6 to 37 (10-59%). Soiling frequency decreased from 4.8 to 1.1 days/week (p <0.001). Abdominal pain decreased from 1.7 to 0.3 days/week (<0.0001), and spontaneous urge to defecate improved. Quality of life (p < 0.01), mean transit index and gastric emptying on NTS improved (p < 0.005).

CONCLUSION

Treatment-resistant STC responds to TES using interferential current across the abdomen when given daily for many months. Battery operated stimulators allowed stimulation at home for an hour each day. Stimulation for six months produced clinically significant improvement in defecation frequency, soiling, abdominal pain, urge to defecate, and quality of life in half of these chronic patients.

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.

The effect of food withdrawal in children with rapid-transit constipation

BACKGROUND

Rapid proximal colonic transit with anorectal holdup is a subtype of chronic constipation linked to food intolerance. We aimed to determine the effectiveness of dietary exclusion as a treatment for constipated children with rapid-transit constipation by scintigraphy.

METHODS

Questionnaires on diet and symptoms were mailed out to 125 children with chronic constipation and rapid proximal colonic transit on nuclear transit study at our institute between 1998 and 2014 years. Patients were given instructions and encouraged to undertake a six-food elimination diet targeting common protein allergens (dairy, wheat, soy, eggs, nuts, seafood). Answers were completed by circling an option or on visual analogue scale. Results were evaluated statistically using GraphPad Prism 6 by a Wilcoxon matched-pairs rank test. P < 0.05 was considered significant.

RESULTS

We received 44/125 responses, 26 patients [mean age 11 years (5-21)] had attempted elimination diet and 18 had not. Dairy and wheat were the most common foods eliminated and symptomatic improvement was greater for patients who had completely eliminated foods. Constipation, abdominal pain and pain on defecation were reduced (p < 0.01). Laxative usage decreased, although this was not statistically significant. Families encountered problems with dietary exclusion, particularly expense. Assistance from a dietician or nutritionist was sought by >50 % of families.

CONCLUSION

Dietary exclusion is a promising strategy to treat constipation in children with rapid proximal colonic transit. However, it was hard for many families, demonstrating the need for identifying the cause more specifically and a better set of instructions for the family and/or dietitian to follow.

Colonic transit in children and adolescents with chronic constipation

OBJECTIVE

The aim of this study was to assess clinical features and colonic transit patterns in Brazilian children with refractory constipation.

METHODS

From 2010 to 2013, 79 constipated patients received follow-up care in a tertiary hospital. Of these patients, 28 (aged 8-14 years) were refractory to conventional therapy and underwent a simplified visual method of nuclear colonic transit study, by ingestion of a liquid meal containing 9.25 MBq/kg of (99m)Tc-phytate. Abdominal static images were taken immediately and at two, six, 24, 30, and 48h after ingestion for qualitative analysis of the radio marker progression through the colon.

RESULTS

Two patterns of colonic transit were found: slow colonic transit (SCT, n=14), when images at 48h showed a larger part of the tracer remained in proximal and transverse colon, and distal retention (DR, n=14), when after 30h, the radio isotope passed the transverse colon and was retained in the rectosigmoid up to 48h. The SCT and DR group included, respectively, nine and ten males; median ages in the nuclear study of 11 and 10 years, p=0.207; median duration of constipation of seven and six years, p=0.599. Constipation appearing during first year age (p=0.04) and report of soft stools (p=0.02) were more common in SCT patients. Palpable abdominal fecal impaction was found only in DR group. Appendicostomy for antegrade continence enema was successful in 4/12 (30%) of SCT patients (median follow-up: 2.4 years).

CONCLUSION

Nuclear transit study distinguished two colonic dysmotility patterns and was useful for guiding refractory patients to specific therapies.

Novel techniques to study colonic motor function in children

Colonic motility is an essential component of normal colonic physiology and it controls essential bodily functions such as stool propulsion, storage, and expulsion. Disordered colonic motility may present with constipation or diarrhea as well as associated symptoms such as bloating, gas, pain, incontinence, and others. In order to assess colonic motor function, practitioners may use studies that either investigate transit time or that evaluate peristaltic activity. Transit time is the result of both the effectiveness of propulsive pressures and the physical characteristics of the stools. Its measurement allows one to quantify the extent and severity of the colonic dysfunction and permits the assessment of response to therapy. Various methods exist to investigate colon transit time and motility. In this review, we will focus on newer techniques for these investigations, including: scintigraphic transit studies, anorectal manometry, colonic manometry, and studies using a wireless motility capsule.

Interobserver variability in the interpretation of colon manometry studies in children

OBJECTIVES

The aim of the present study was to evaluate the variability in interpretation of colon manometry (CM) in children.

METHODS

Fifty-seven colon motility studies were independently reviewed by 5 observers. Each observer was required to report on the colonic motility during fasting, after administration of a meal, and after bisacodyl stimulation. They were also asked to comment whether CM study was normal or abnormal and whether in their opinion the postprandial recording provided clinically useful information.

RESULTS

The median (range) agreement regarding the presence of high-amplitude propagating contractions (HAPC) was 83% (80%-92%). The interpretation of gastrocolonic response produced the most inconsistent results with median (range) agreemnet of 64% (53%-95%). The postprandial period was reported to be useful in only 3% to 24% of the studies. The median (range) agreement regarding the overall interpretation of the study being either normal or abnormal was 87% (83%-90%).

CONCLUSIONS

The most easily recognizable contraction pattern during CM is the high-amplitude propagating contractions. Visual interpretation of the gastrocolonic response produces the most inconsistent results and maximum variability. Abbreviated CM studies without the postprandial period or routine calculation of the motility index to evaluate gastrocolonic response can help make colon manometries more objective and reliable.

The impact of transcutaneous electrical stimulation therapy on appendicostomy operation rates for children with chronic constipation--a single-institution experience

PURPOSE

Appendicostomy for antegrade continence enema is a minimally invasive surgical intervention that has helped many children with chronic constipation. At our institution, since 2006, transcutaneous electrical stimulation (TES) has been trialed to treat slow-transit constipation (STC) in children. This retrospective audit aimed to determine if TES use affected appendicostomy-formation rates and to monitor changes in practice. We hypothesized that appendicostomy rates have decreased for STC but not for other indications.

METHODS

Appendicostomy-formation rate was determined for the 5 years before and after 2006. Children were identified as STC or non-STC from nuclear transit scintigraphy and patient records.

RESULTS

Since 1999, 317 children were diagnosed with STC using nuclear transit scintigraphy with 121 during 2001 to 2005 (24.2/year) and 147 during 2006 to 2010 (29.4/year). Seventy-four children had appendicostomy formation. For 2001 to 2005, appendicostomy-formation rates for STC and non-STC children were similar: 5.4 per year (n = 27) and 4.8 per year (n = 24), respectively. For 2006 to 2010, appendicostomy-formation rates were 1.2 per year (n = 6) for STC and 3.2 per year (n = 16) for non-STC (χ(2), P = .04).

CONCLUSION

Since 2006, appendicostomy-formation rates have significantly reduced in STC but not in non-STC children at our institute, coinciding with the introduction of TES as an alternative treatment for STC. Transcutaneous electrical stimulation has not been tested on non-STC children in this period.

How common is colonic elongation in children with slow-transit constipation or anorectal retention?

PURPOSE

Colonic elongation is reported as a possible cause for slow colonic transit, as it is observed in patients with slow-transit constipation (STC). This study aimed to determine the frequency of colonic elongation in children with STC or anorectal retention using radioimaging. We hypothesized that transverse colon elongation may occur in patients with STC, whereas sigmoid colon elongates in patients with anorectal retention.

METHODS

Nuclear transit scintigraphy performed for chronic constipation (1999-2011) was analyzed qualitatively for elongated transverse colon or sigmoid colon. Three major colonic transit patterns were identified: slow transit in the proximal colon (STC), normal proximal colonic transit with anorectal retention (NT-AR), and rapid proximal transit ± anorectal retention (RT). χ(2) Test was used for statistical analysis (P < .05 significant).

RESULTS

From 1999 to 2011, 626 children had nuclear transit scintigraphy. Transverse colon elongation occurred more frequently in STC (73/322, or 23%) compared with NT-AR (9/127, or 7%) and RT (5/177, or 3%; P < .0001). Sigmoid colon elongation was equally common in NT-AR (8/127, or 6%) compared with RT (10/177, or 6%) and STC (14/322, or 4%; P < .9).

CONCLUSION

Transverse colon elongation is more common in STC (23%), whereas sigmoid colon elongation is not more common in anorectal retention. Colonic elongation may be the cause or the result of the underlying slow colonic transit.

Home transcutaneous electrical stimulation to treat children with slow-transit constipation

PURPOSE

This study aimed to test the effectiveness of home transcutaneous electrical stimulation (TES) when patients with slow-transit constipation (STC) were trained by a naive clinician.

METHODS

A surgeon was trained to teach the TES method to STC children who then self-administered at home (1 hour a day, 3-6 months) using a battery-powered interferential stimulator. Bowel diaries, PedsQL4.0 questionnaires, and radio-nuclear colonic transit studies were completed before and after treatment.

RESULTS

Thirty-two children (16 female; mean age, 8.3 years; range, 3-17 years) self-administered 3 to 6 months of TES. Three did not return diaries. Group 1 (n = 13) started with less than 3 bowel actions per week, and group 2 (n = 16), with more than 3 bowel actions per week. Defecation frequency increased in 69% of group 1 (mean, 1.4-3.0 per week; P = .02). Soiling frequency decreased in 50% of group 2 (5.4-1.9 per week, P = .04). Of 13 patients, 7 improved with development of urge-initiated defecation. Abdominal pain decreased in 48% (1.6 episodes per week to 0.9 per week, P = .06). Stool consistency improved in 56%. There was significant improvement in child-reported and parent-reported PedsQL Scores. Colonic transit improved in 13 of 25 patients.

CONCLUSION

Home TES provides a new treatment for STC children, with 50% of treatment-resistant patients benefited. Success requires clinician training and close patient contact. Transcutaneous electrical stimulation increased defecation and reduced soiling.

Long-term effects of transabdominal electrical stimulation in treating children with slow-transit constipation

AIMS

Transcutaneous electrical stimulation (TES) was used to treat children with slow-transit constipation (STC) for 1 to 2 months in a randomized controlled trial during 2006 to 2008. We aimed to determine long-term outcomes, hypothesizing that TES produced sustained improvement.

METHODS

Physiotherapists administered 1 to 2 months of TES to 39 children (20 minutes, 3 times a week). Fifteen continued to self-administer TES (30 minutes daily for more than 2 months). Mean long-term follow-up of 30 of 39 patients was conducted using questionnaire review 3.5 years (range 1.9-4.7 years) later. Outcomes were evaluated by confidence intervals or paired t test.

RESULTS

Seventy-three percent of patients perceived improvement, lasting more than 2 years in 33% and less than 6 months in 25% to 33%. Defecation frequency improved in 30%. Stools got wetter in 62% after stimulation and then drier again. Soiling improved in 75% and abdominal pain in 59%. Laxative use stopped in 52%, and 43% with appendicostomies stopped washouts. Soiling/Holschneider continence score improved in 81% (P = .0002). Timed sits switched to urge-initiated defecations in 80% patients. Eighty percent of relapsed patients elected to have home stimulation.

CONCLUSION

TES holds promise for STC children. Improvement occurred in two thirds of children, lasting more than 2 years in one third, whereas symptoms recurred after 6 months in one third of children.

Slow-transit constipation with concurrent upper gastrointestinal dysmotility and its response to transcutaneous electrical stimulation

PURPOSE

Transcutaneous electrical stimulation (TES) speeds up colonic transit in children with slow-transit constipation (STC). This study examined if concurrent upper gastrointestinal dysmotility (UGD) affected response to TES.

METHODS

Radio-nuclear transit studies (NTS) were performed before and after TES treatment of STC as part of a larger randomised controlled trial. UGD was defined as delayed gastric emptying and/or slow small bowel transit. Improvement was defined as increase of ≥1 Geometric Centre (median radiotracer position at each time [small bowel = 1, toilet = 6]).

RESULTS

Forty-six subjects completed the trial, 34 had NTS after stimulation (21 M, 8-17 years, mean 11.3 years; symptoms >9 years). Active stimulation increased transit in >50% versus only 25% with sham (p = 0.04). Seventeen children also had UGD. In children with STC and either normal upper GI motility (NUGM) and UGD, NTS improved slightly after 1 month (57 vs. 60%; p = 0.9) and more after 2 months (88 vs. 40%; p = 0.07). However, mean transit rate significantly increased with NUGM, but not UGD (5.0 ± 0.2: 3.6 ± 0.6, p < 0.01).

CONCLUSION

Transcutaneous electrical stimulation was beneficial for STC, with response weakly associated with UGD. As measured by NTS, STC children with NUGM responded slightly more, but with significantly greater increased transit compared to those with UGD. Higher numbers are needed to determine if the difference is important.

Nuclear transit studies of patients with intractable chronic constipation reveal a subgroup with rapid proximal colonic transit

AIMS/BACKGROUND

Nuclear transit studies (NTS) allow us to follow transit through the stomach and the small and large intestines. We identified children with chronic constipation with rapid proximal colonic transit and characterized their clinical features.

METHODS

We reviewed NTS from 1998 to 2009 to identify patients with chronic constipation and rapid proximal colonic transit, defined as greater than 25% of tracer beyond hepatic flexure at 6 hour and/or greater than 25% of tracer beyond end of descending colon at 24 hour. This was correlated with clinical symptoms and outcome from patient records.

RESULTS

Five hundred twenty children with chronic constipation underwent investigation by NTS, and 64 (12%) were identified with rapid proximal colonic transit. The clinical history, symptoms, and outcome in 55 of 64 available for analysis frequently showed family history of allergy (10.9%) and symptoms associated with food allergy/intolerance: abdominal pain (80%), anal fissure (27.3%), and other allergic symptoms (43.6%). Eighteen children were treated with dietary exclusion, with resolution of symptoms in 9 (50%).

CONCLUSIONS

Some children with intractable chronic constipation have rapid proximal colonic transit, have symptoms consistent with possible food allergy/intolerance, and may respond to dietary exclusion. The NTS can identify these patients with rapid proximal transit that may be secondary to food intolerance.

Gender differences in reduced substance P (SP) in children with slow-transit constipation

PURPOSE

Adult slow-transit constipation (STC) occurs predominantly in females and is associated with low numbers of substance P (SP)-containing nerves in colonic circular muscle.

AIM

To determine if reduced SP nerves is female predominant in paediatric STC.

METHODS

Children with STC were identified from records of more than 600 nuclear transit studies (NTS) and intestinal biopsies done for intractable chronic constipation between November 1998 and March 2009. Colonic seromuscular biopsies collected from hepatic and splenic flexures, and sigmoid colon were processed for immunohistochemistry. Nerve fibre density in circular muscle containing SP was measured qualitatively by a pathologist.

RESULTS

Eighty-eight children with chronic constipation had both NTS and intestinal biopsies. Seventy-eight children (52 M; age 2-15.5 years; mean 7.7 years) had STC diagnosed by NTS. SP was reduced in 10/26 girls, but only 11/52 boys.

CONCLUSION

In this sample, STC was more common in boys than girls. However, in girls with STC, SP deficiency occurred in 40%, when compared with 20% of boys. During puberty, the percentage of girls with reduced SP decreased, whilst the percentage of boys increased. These results suggest that STC is heterogeneous and that there are some gender differences, the implication of which requires further investigation.

Substance P and vasoactive intestinal peptide are reduced in right transverse colon in pediatric slow-transit constipation

BACKGROUND

Slow-transit constipation (STC) is recognized in children but the etiology is unknown. Abnormalities in substance P (SP), vasoactive intestinal peptide (VIP) and nitric oxide (NO) have been implicated. The density of nerve fibers in circular muscle containing these transmitters was examined in colon from children with STC and compared to other pediatric and adult samples.

METHODS

Fluorescence immunohistochemistry using antibodies to NO synthase (NOS), VIP and SP was performed on colonic biopsies (transverse and sigmoid colon) from 33 adults with colorectal cancer, 11 children with normal colonic transit and anorectal retention (NAR) and 51 with chronic constipation and slow motility in the proximal colon (STC). The percentage area of nerve fibers in circular muscle containing each transmitter was quantified in confocal images.

KEY RESULTS

In colon circular muscle, the percentage area of nerve fibers containing NOS > VIP > SP (6 : 2 : 1). Pediatric groups had a higher density of nerve fibers than adults. In pediatric samples, there were no regional differences in NOS and VIP, while SP nerve fiber density was higher in sigmoid than proximal colon. STC children had lower SP and VIP nerve fiber density in the proximal colon than NAR children. Twenty-three percent of STC children had low SP nerve fiber density.

CONCLUSIONS & INFERENCES

There are age-related reductions in nerve fiber density in human colon circular muscle. NOS and VIP do not show regional variations, while SP nerve fiber density is higher in distal colon. 1/3 of pediatric STC patients have low SP or VIP nerve fiber density in proximal colon.

What is new in radiology and pathology of motility disorders in children?

Disorders affecting colorectal motility lead to significant morbidity in children with surgical conditions. Etiology is frequently unknown, which in turn makes treatment empiric and compromises outcome. A thorough understanding of the normal mechanisms of control and the ability to recognize and manage defects is an important goal for clinicians. This article reviews recent advances made in the investigation of children with colorectal motility disorders, including the role of transit studies (marker studies and scintigraphy), options for assessing anatomy (ultrasound, contrast enema, and sectional imaging) and the use of manometry, both anorectal and colonic. Current concepts in microscopic evaluation are outlined.

Standard medical therapies do not alter colonic transit time in children with treatment-resistant slow-transit constipation

BACKGROUND

Slow transit constipation (STC) is a form of chronic constipation characterised by prolonged passage of faecal matter through the colon. It is diagnosed by demonstrating delayed colonic transit on gastrointestinal transit studies. Traditionally, radio-opaque marker studies are performed. Recently, radioisotope nuclear transit studies (NTS) have been used in our centre to assess gastrointestinal transit time. This study aimed to evaluate if there are changes in colonic transit in STC children resistant to standard medical treatment over a prolonged period.

METHODS

Children with STC resistant to standard medical therapy for > or =2 years who had undergone two separate NTS to assess their colonic transit (where the first study had identified slow colonic transit without anorectal retention) were identified after ethical approval. The geometric centre (GC) of radioisotope activity at 6, 24, 30 and 48 h was compared in the two transit studies to determine if changes occurred.

RESULTS

Seven children (4 males) with proven STC resistant to standard medical therapy and two transit studies performed at different times were identified. Mean age was 7.0 years (5.4-10.8 years) at first study, and 11.4 years (9.7-14.2 years) at second study, with a mean of 4.4 years (1-8.5 years) between studies. There was no significant difference in colonic transit at any timepoint in the two tests (paired t test).

CONCLUSIONS

We conclude that nuclear transit studies are reproducible in assessing slow colonic transit in children with treatment-resistant STC and demonstrate that conventional medical treatment over many years has no effect on underlying colonic motility.