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

How do we define therapy-resistant constipation in children aged 4-18 years old? A systematic review with meta-narrative synthesis

BACKGROUND

Therapy-resistant constipation often is a frustrating clinical entity recognised by the persistence of infrequent and painful bowel movements faecal incontinence and abdominal pain despite intensive treatment. It is important to clearly define therapy-resistant constipation before children are subjected to invasive diagnostic and therapeutic procedures.

AIM

To conduct a systematic review determining how paediatric interventional studies define therapy-resistant constipation.

METHOD

We searched CENTRAL, MEDLINE, Embase, WHO ICTR and ClinicalTrials.gov. Studies that included patients with therapy-resistant constipation were identified. Data were extracted on criteria used for defining therapy-resistant constipation and reported using a meta-narrative approach highlighting areas of convergence and divergence in the findings.

RESULTS

A total of 1553 abstracts were screened in duplicate, and 47 studies were included in the review. There were at least seven definitions used in the paediatric literature to define medically resistant constipation. The term intractable was used in 24 articles and 21 used the term refractory to describe therapy-resistant constipation. Out of them, only 14 articles have attempted to provide an explicit definition including a predefined time and prior therapy. There were 10 studies without a clear definition for therapy-resistant constipation. The duration before being diagnosed as therapy-resistant constipation varied from 1 months to 2 years among studies. Seven studies employed the Rome criteria (Rome III or Rome IV) to characterising constipation while five adopted the Rome III and European and North American paediatric societies definition of paediatric gastroenterology, hepatology and nutrition guideline of management of constipation in children.

CONCLUSION

The current literature has no explicit definition for therapy-resistant constipation in children. There is a need for a detailed consensus definition to ensure consistency of future research and to avoid unnecessary and maybe even harmful, invasive diagnostic and therapeutic interventions.

Imaging in pediatric disorders of the gut-brain interactions: current best practice and future directions

INTRODUCTION

Disorders of Gut-Brain Interactions (DGBI) are a common clinical problem in children and pose significant challenges to the attending pediatrician. Radiological investigations are commonly ordered to evaluate these children.

AREA COVERED

This review focuses on the current best practice of using radiological investigations in DGBIs and how novel radiological investigations could revolutionize the assessment and therapeutic approach of DGBI in children.

EXPERT OPINION

We believe imaging in DGBI is still in its early stages, but it has the potential to revolutionize how we diagnose and treat children with DGBI. As the understanding of the gut-brain axis continues to grow, we can expect to see the disappearance of conventional imaging techniques and the emergence of more sophisticated imaging techniques with less radiation exposure in the future which provide more clinically meaningful information regarding the gut-brain axis and its influence on intestinal function. Some of the novel imaging modalities will be able to broaden our horizon of understanding DGBI in children providing more useful therapeutic options to minimize their suffering.

Can Lactose Intolerance Be a Cause of Constipation? A Narrative Review

Lactose intolerance and constipation are common in children and impact everyday life, not only for patients but also their families. Both conditions can be comorbid with other diseases or form a part of their clinical presentation, but constipation is not usually associated with lactose intolerance. The typical symptoms of lactose intolerance include abdominal pain, bloating, flatus, diarrhoea, borborygmi, and less frequently nausea and vomiting. In approximately 30% of cases, constipation can be a symptom of lactose intolerance. Constipation is characterized by infrequent bowel movements, hard and/or large stools, painful defecation, and faecal incontinence, and is often accompanied by abdominal pain. This paper provides a narrative review on lactose intolerance, its epidemiology, pathogenesis, the correlation between lactose intolerance and constipation in children, and potential mechanisms of such association.

Cows' Milk Allergy-Associated Constipation: When to Look for It? A Narrative Review

Constipation is a very common disorder, mostly functional in nature, that may persist for years in up to 35-52% of children. Food allergy prevalence, severity and persistence are increasing over time, and cows' milk protein is the commonest food allergen recognised to affect gastrointestinal motility in children. There is mounting evidence of the role of cows' milk (CM) allergy (CMA) in children with constipation. With this narrative review, we aim to provide clinicians with an updated and critical overview of food allergy-associated constipation. We searched Embase, Medline and the Cochrane Library, using keywords related to the topic. Only reviews and studies including children aged 0-17 years that were published in English were considered. Constipation has been reported in 4.6% of infants with CMA; the prevalence of food allergy underlying chronic constipation in children resistant to conventional treatment and presenting to tertiary clinics ranges between 28% and 78%. The identification of predisposing risk factors and of a specific phenotype of food allergy-induced constipation remains elusive. No allergic tests, radiological or motility investigations achieve sufficient sensitivity and specificity to screen children for CMA-related constipation. A 4-week cows' milk protein (CMP) elimination diet may be considered for children with chronic constipation resistant to conventional treatment and who lack alarm sign/symptoms of organic diseases. In subjects with ameliorated symptoms on CMP elimination, the diagnosis of CMA should be confirmed by a food challenge to avoid an unnecessary protracted diet.

Colon Transit Scintigraphy in Schaaf-Yang Syndrome

ABSTRACT

Schaaf-Yang syndrome is a genetic disorder characterized by delayed psychomotor development, hypotonia, intellectual disability, feeding difficulties, and variable dysmorphic facial features. It is an extremely rare disorder with over 250 cases reported in the medical literature. This condition has been determined to be inherited by an autosomal dominant pattern. We present colon transit scintigraphy of a 6-year-old boy with history of chronic constipation with poor response to medical treatment, clinical characteristics, and gene mutations consistent with this syndrome. After oral administration of 111In-DTPA, planar and SPECT/CT images showed rapid proximal colonic transit and anorectal retention.

Paediatric constipation for general paediatricians: Review using a case-based and evidence-based approach

Constipation is a common problem in childhood. The most common type of constipation is functional, accounting for 90-95% of all cases. The aim of this review is to provide clinical scenarios with treatment using evidence-based information, and management strategies and a clinical algorithm to guide the management of constipation in children. Recent guidelines and online information sites are detailed. Clinical red flags and organic causes of constipation are included. Four clinical scenarios are presented: case (1) 4-month-old child with constipation since birth and likely Hirschsprung disease; case (2) 6-month-old infant with infant dyschezia; case (3) 4-year old with functional constipation; and; case (4) 9-year old with treatment resistant constipation. Children with functional constipation need a thorough history and physical exam to rule out the presence of any 'red flags' but do not require laboratory investigations. Management includes education and demystification, disimpaction followed by maintenance therapy with oral laxatives, dietary counselling and toilet training. Treatment options differ between infants and children. Disimpaction and maintenance regimens for common laxatives are presented. On treatment failure or on suspicion of organic disease the patient should be referred for further evaluation. The radionuclide intestinal transit study (scintigraphy) is a useful modality for evaluation and planning of management in treatment-resistant children. Treatment options for treatment-resistant patients are presented. High-level evidence (meta-analyses) for pharmalogical and non-pharmalogical treatment modalities are reviewed and an algorithm for assessment and treatment are presented.

Treatment of childhood constipation: a synthesis of systematic reviews and meta-analyses

Introduction: Constipation occurs in many children and can become chronic. Many grow out of it but for one third, it continues into adulthood. For most patients, there is no identifiable organic disorder and it is classified as functional constipation.Areas covered: In 2016, treatment of childhood constipation was extensively reviewed by Rome IV. This review covers meta-analyses and evidence for treatment of paediatric constipation since 2016 and new emerging treatments.Expert opinion: Since 2016, meta-analyses conclude 1) fibre should be included in a normal diet, but further supplementation does not improve constipation; 2) probiotics may increase stool frequency in children, but evidence from larger RCTs is needed; 3) comparing laxatives, polyethylene glycol (PEG) is superior to placebo, lactulose and milk of magnesia, and 4) appendix stomas are effective and should be considered before surgery. Emerging areas of study include food intolerance, electrical stimulation and faecal microbiota transplant. For research, outcome measures need standardising to allow comparison between studies and allow meta-analyses. To assist this, validated GI instruments have been developed by Rome IV and PedsQl.

'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.

Dietary exclusion of fructose and lactose after positive breath tests improved rapid-transit constipation in children

Aims

Exclusion of fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) from the diet is effective in alleviating symptoms of irritable bowel syndrome (IBS) in adults. Rapid‐transit constipation (RTC) is a recently discovered subset of chronic constipation and has been linked to food intolerance. The aim of this study was to audit the effect of specific FODMAP elimination diets in children with RTC.

Methods

This was an audit of children presenting to a tertiary children's hospital surgeon with refractory chronic constipation who had rapid transit in the proximal colon on nuclear imaging; had hydrogen/methane breath tests for fructose, lactose, and/or sorbitol intolerance; and were advised to exclude positive sugar under clinical supervision. Patients filled in a questionnaire rating severity of constipation, abdominal pain, and pain on defecation with a visual analogue scale (VAS, 0 = none, 10 = high) and stool consistency for 6 months before and after dietary exclusion.

Results

In responses from 29 children (5–15 years, 21 males), 70% eliminated fructose, and 40% eliminated lactose. There was a significant reduction in the severity of constipation (VAS mean ± SEM, pre 5.8 ± 0.5 vs post 3.3 ± 0.6, P < 0.0001), abdominal pain (5.1 ± 0.6 vs 2.8 ± 0.5, P = 0.0004), pain on defecation (5.8 ± 0.6 vs 2.6 ± 0.5, P < 0.0001), and increase in stool wetness (Bristol Stool Scale pre 3.3 ± 0.3 vs post 3.9 ± 0.2, P = 0.004).

Conclusion

Children with RTC showed significant improvements in constipation and pain after excluding the sugar indicated by positive breath tests, suggesting that specific sugar‐exclusion diets may have a role in the management of RTC in children.

Gastrointestinal transit scintigraphy in chronic constipation evaluation in pediatric age; an infrequent test

AIM

Chronic constipation is a common pathology in children. The aim of this paper was to show the usefulness of gastrointestinal transit scintigraphy in pediatric patients with chronic constipation, and the advantages with respect to other imaging techniques, despite our limited experience.

MATERIAL AND METHODS

We evaluated 5 patients sent to our service with a diagnosis of chronic constipation refractory to treatment. We performed a complete study protocol, including liquid gastric emptying scintigraphy and small and large bowel transit times, using a single dose of ¹¹¹In-DTPA. Following international guidelines regions of interest were defined in stomach, terminal ileum and in 6 regions of the large intestine.

RESULTS

All patients showed altered scintigraphy study, showing 4 of them normal radiological tests. Radioisotopic study changed diagnosis in 2 patients and in other 2 patients contributed to clarify it, since discordance between normal radiological tests and abnormal rectal biopsy. One of the patients showed concordance between each imaging modality. The results of the test changed the therapeutic management in 2 cases.

CONCLUSIONS

Our limited experience coincides with published data in which scintigraphy study turns out to be a reproducible and accurate method. It provides physiological, quantitative and useful information in the study of constipation, being the unique exploration that allows both global and regional gastrointestinal transit time determination.

Gastrointestinal Motility, Part 2: Small-Bowel and Colon Transit

Because of the difficulty often encountered in deciding whether a patient's symptoms originate in the upper or lower gastrointestinal tract, gastrointestinal transit scintigraphy is a uniquely suited noninvasive, quantitative, and physiologic method of determining whether there is a motility disorder affecting the stomach, small bowel, or colon. Small-bowel and colon transit studies can be performed alone or together with gastric emptying studies after oral administration of an appropriately radiolabeled meal. It is hoped that newly published standards for performing these studies and the anticipated arrival of new Current Procedural Terminology codes in the United States for small-bowel and colon transit studies will increase their availability and use.

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.

Predictors of slow colonic transit in children

PURPOSE

Slow transit constipation (STC) and functional fecal retention (FFR) are two forms of severe intractable constipation in childhood diagnosed by nuclear transit studies (NTS). This retrospective study aims to identify the predicting factors for STC and FFR by looking at the association with neuropsychiatric disorders (NPD), obesity, family history of constipation and atopic disease.

PATIENTS AND METHODS

A retrospective chart review was conducted on children with intractable constipation referred for NTS between 1st April 2003 and 1st April 2014. Comparisons were made between STC, FFR and normal transit patients with regards to NPD, obesity (BMI z score >95th percentile), family history of constipation in first and second-degree relatives and atopic disease which included food allergy, asthma and eczema.

RESULTS

Between 2003 and 2014, 97 patients were referred for a NTS. Out of 36 patients with NPD, 21 (58.3 %) had STC and 13 (36.1 %) had FFR (p < 0.05). 15.8 % of patients with constipation were obese, compared to 6.4 % in the general Australian paediatric population (p < 0.05). There was no significant association between constipation and atopic disease or family history.

CONCLUSION

Neuropsychiatric disorders, in particular autism, are useful predictors of STC and FFR in children. Obesity may be associated with a higher risk of developing chronic constipation.

Curative effect of Biantong capsules combined with mosapride in treatment of constipation after hemorrhoid surgery in elderly patients

AIM: To assess the curative effect of Biantong capsules combined with mosapride in the treatment of constipation in elderly patients after hemorrhoid surgery.

METHODS: Seventy-eight elderly patients with constipation who had undergone hemorrhoid surgery at Nanyang Central Hospital were randomly divided into either an observation group or a control group (n = 39 for each). The observation group was treated with Biantong capsules plus mosapride, and the control group was treated with mosapride alone. The curative effect was compared between the two groups.

RESULTS: Two patients in the observation group developed loose stool, which was relieved after continued treatment. Six patients in the control group developed abdominal pain, which was resolved after enema administration. No liver function abnormalities were observed in either group. In the observation group, 26 (66.7%) cases were cured, 7 (17.9%) cases showed a significant response, 4 (10.3%) cases showed a partial response, and 2 (5.1%) cases showed no response; the corresponding figures in the control group were 17 (43.6%), 4 (10.3%), 10 (25.9%) and 8 (20.5%), respectively. The total response rate was significantly higher in the treatment group than in the control group (94.9% vs 79.5%, P < 0.05).

CONCLUSION: Biantong capsules combined with mosapride has a good curative effect in the treatment of constipation in elderly patients after hemorrhoid surgery.

Fusion of gamma scintigraphic and magnetic resonance images improves the anatomical delineation of radiotracer for the assessment of gastrointestinal transit

OBJECTIVES

This paper describes the use of gamma scintigraphic and magnetic resonance (MR) fusion images for improving the anatomical delineation of orally administered radiotracers used in gastrointestinal (GI) transit investigations.

METHODS

Ten healthy volunteers ingested enteric-coated gelatin capsules containing 4.4 ± 1.1 MBq SmCl3-labelled resin. Four external body markers containing Sm and Gd-DTPA were placed on the left and right lower costal margins and iliac crests of each volunteer. Anterior and posterior planar images were acquired hourly for 9 h, followed by a final single photon emission computed tomography (SPECT) image and subsequent T1-weighted images using a 1.5 T MR system. Coronal scintigraphic images were fused with MR images and assessed for diagnostic information.

RESULTS

The fused images revealed a combination of the tissue and organ anatomy with an overlay of the distribution of the tracer. Compared with conventional scintigraphic imaging alone, SPECT-MR fused images improved the localization of spatial and temporal movements of the radiotracer throughout the GI tract.

CONCLUSION

Fusion of SPECT and MR images in conjunction with sequential scintigraphic images improved the assessment of segmental GI transit. These have the potential to provide more accurate diagnostic results and are visually powerful images that would have more widespread acceptance by nonspecialists.

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.

Pathophysiology of chronic childhood constipation: functional and morphological evaluation by anorectal manometry and endosonography and colonic transit study

BACKGROUND

Chronic idiopathic constipation (IC) is a common problem in children. We hypothesised that hypertonicity and overactivity of the internal anal sphincter (IAS) contributed to childhood IC.

METHOD

This was a prospective study of children who were admitted for investigation and treatment of chronic constipation at the gastrointestinal motility clinic in Guy's and St. Thomas' Hospital, NHS Foundation Trust, London. All children had a colonic transit marker study followed by anorectal manometry and anal endosonography under ketamine anesthesia. We used a validated symptom severity (SS) score questionnaire for assessment of constipation and fecal incontinence on admission to hospital and during follow-up for 12months. The SS score of 0 was the best and 65 the worst.

RESULTS

Of 92 children, 57 were male and median (range) age was 8.46years (3.35-14.97). Duration of symptoms was 4.7years (0.3-13). Soiling was present in 88 (96%) patients, delay in defecation of once every 2 to 3days or less frequently in 86 (93%) and a palpable fecaloma (megarectum) on abdominal examination in 76 (83%). 42 children had 'fecal impaction' requiring disimpaction of stool from the rectum under general anesthesia and 50 had 'no impaction'. The median IAS resting pressure was within the normal range measuring 55mm Hg (25-107) and median amplitude and frequency of the IAS contractions were 10mm Hg (2.0-58) and 17cycles per min (5.0-34), respectively. The median IAS thickness was 0.93mm (0.5-2.0). There was no correlation between amplitude and frequency of anorectal contractions and anal sphincter resting pressure. The mean right colonic transit time was 8.55 (standard deviation ±13.22) h, left colonic transit time was 11.51h (±13.21), rectosigmoid transit time was 25.91h (±18.89) and total colonic transit time was 45.97h (±17.69).

CONCLUSION

The anal sphincter resting pressure is normal in children with chronic IC. Increased frequency and amplitude of IAS contractions seen in these patients do not cause raised anal sphincter resting pressure or obstructive defecation. Further studies should be done to investigate the role of external anal sphincter dysfunction in pathophysiology of childhood constipation and fecal incontinence.

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.