Rectal compliance and rectal sensation in constipated adolescents, recovered adolescents and healthy volunteers

Diagnostic and therapeutic approach to children with chronic refractory constipation: Consensus report by the SIGENP motility working group

Constipation is a common problem in children, accounting for about 3% of all primary care visits and up to 25% of referrals to paediatric gastroenterologists. Although polyethylene glycol often proves effective, most children require prolonged treatment and about 50% of them have at least one relapse within the first 5 years after initial recovery. When conventional treatment fails, children are considered to have refractory constipation. Children with refractory constipation deserve specialist management and guidance. Over the last decades, 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. The present review analyses the possible diagnostic investigations for children with refractory constipation, focusing on their actual indications and their utility in clinical practice. Moreover, we have also analytically reviewed medical and surgical therapeutic options, which should be considered in selected patients in order to achieve the best clinical outcome.

Evaluation of Chronic Constipation in Children With Autism Spectrum Disorder

OBJECTIVES

Chronic constipation occurs frequently in children with autism spectrum disorder (ASD). The primary objective was to determine whether chronic constipation is associated with a higher rate of abnormal colonic motor activity in ASD children than in non-ASD children. A secondary goal was to determine if clinical variables could identify children with ASD at risk for possessing abnormal colonic motility.

METHODS

A retrospective, propensity-matched, case-control study compared colonic manometry (CM) of an ASD cohort and non-ASD controls with chronic constipation. Clinical variables were evaluated as potential predictors for abnormal colonic motility.

RESULTS

Fifty-six patients with ASD and 123 controls without the diagnosis of ASD who underwent CM were included. Propensity score resulted in 35 matched cohorts of ASD and controls. The rate of abnormal CM findings between ASD and matched controls (24% vs 20%, P = 0.78) did not differ significantly. A prediction model of abnormal CM that included ASD diagnosis, duration of constipation, and soiling achieved a sensitivity of 0.94 and specificity of 0.65. The risk for abnormal colonic motility increased 11% for every 1-year increase in duration of constipation. Odds for abnormal motility were 30 times higher in ASD children with soiling than controls with soiling (P < 0.0001).

CONCLUSIONS

Chronic constipation does not appear to be associated with a higher rate of abnormal colonic motility in children with ASD. Clinical information of disease duration and presence of soiling due to constipation show promise in identifying patients with ASD at a greater risk for abnormal colonic motility.

Childhood constipation: Current status, challenges, and future perspectives

Constipation in children is a major health issue around the world, with a global prevalence of 9.5%. They present to clinicians with a myriad of clinical signs. The Rome IV symptom-based criteria are used to diagnose functional constipation. Functional constipation is also a huge financial burden for healthcare system and has a detrimental impact on health-related quality of life of children. There are various risk factors identified globally, including centrally connected factors such as child abuse, emotional and behavioral issues, and psychological stress. Constipation is also precipitated by a low-fiber diet, physical inactivity, and an altered intestinal microbiome. The main pathophysiological mechanism is stool withholding, while altered rectal function, anal sphincter, pelvic floor, and colonic dysfunction also play important roles. Clinical evaluation is critical in making a diagnosis, and most investigations are only required in refractory patients. In the treatment of childhood constipation, both nonpharmacological (education and de-mystification, dietary changes, toilet training, behavioral interventions, biofeedback, and pelvic floor physiotherapy), and pharmacological (osmotic and stimulant laxatives and novel drugs like prucalopride and lubiprostone) interventions are used. For children with refractory constipation, transanal irrigation, botulinum toxin, neuromodulation, and surgical treatments are reserved. While frequent use of probiotics is still in the experimental stage, healthy dietary habits, living a healthy lifestyle and limiting exposure to stressful events, are all beneficial preventive measures.

Functional Constipation and Dyssynergic Defecation in Children

Defecation is a complex physiological process, which relies on intricate mechanisms involving the autonomic and somatic nervous system, the pelvic floor muscles, and the anal sphincter complex. Anorectal dysfunction may result in constipation, a bothersome defecation disorder that can severely affect daily lives of children and their families. In this review, we focus on different mechanisms underlying anorectal dysfunction and specific treatment options aimed at improving defecation dynamics in children with functional constipation.

European society of neurogastroenterology and motility guidelines on functional constipation in adults

INTRODUCTION

Chronic constipation is a common disorder with a reported prevalence ranging from 3% to 27% in the general population. Several management strategies, including diagnostic tests, empiric treatments, and specific treatments, have been developed. Our aim was to develop European guidelines for the clinical management of constipation.

DESIGN

After a thorough review of the literature by experts in relevant fields, including gastroenterologists, surgeons, general practitioners, radiologists, and experts in gastrointestinal motility testing from various European countries, a Delphi consensus process was used to produce statements and practical algorithms for the management of chronic constipation.

KEY RESULTS

Seventy-three final statements were agreed upon after the Delphi process. The level of evidence for most statements was low or very low. A high level of evidence was agreed only for anorectal manometry as a comprehensive evaluation of anorectal function and for treatment with osmotic laxatives, especially polyethylene glycol, the prokinetic drug prucalopride, secretagogues, such as linaclotide and lubiprostone and PAMORAs for the treatment of opioid-induced constipation. However, the level of agreement between the authors was good for most statements (80% or more of the authors). The greatest disagreement was related to the surgical management of constipation.

CONCLUSIONS AND INFERENCES

European guidelines on chronic constipation, with recommendations and algorithms, were developed by experts. Despite the high level of agreement between the different experts, the level of scientific evidence for most recommendations was low, highlighting the need for future research to increase the evidence and improve treatment outcomes in these patients.

Anorectal manometry in children with retentive fecal incontinence: What parameters should we evaluate?

INTRODUCTION

Children with functional constipation frequently present with alterations in rectal compliance and the urge-to-defecate sensation that can be evaluated through anorectal manometry (ARM). In the present study, we evaluated the usefulness of the parameters obtained through ARM in children with retentive fecal incontinence (RFI).

MATERIALS AND METHODS

Children with functional constipation, aged 4 to 17years, that underwent ARM were included in the study.

RESULTS

Of the 35 children evaluated, 21 presented with functional constipation and 14 had functional constipation and RFI. The children with both constipation and RFI tolerated greater volumes of air insufflation for triggering the urge to defecate and reaching maximum tolerance of pain, compared with the children that did not have RFI. We identified the cutoff point of 135ml of air as the maximum tolerance sensation for distinguishing children with RFI.

CONCLUSIONS

Maximum tolerance of pain was the most useful parameter for evaluating RFI in children with functional constipation.

Normal Rectal Filling Sensations in Patients with an Enlarged Rectum

BACKGROUND

Increased rectal volume is believed to be associated with diminished rectal sensation, i.e., rectal hyposensitivity.

AIMS

To demonstrate that patients with increased rectal volumes do not automatically have diminished rectal filling sensations.

METHODS

We, retrospectively, observed 100 adult patients with defecation problems, and 44 healthy controls who had undergone anorectal function tests. Using the balloon retention test, we analyzed the distribution of rectal volumes and pressures at different rectal filling sensation levels.

RESULTS

We found variance in the distribution of rectal volumes at all levels, while rectal pressures showed a normal distribution. We found no correlation between rectal volumes and pressures (constant sensation, r = 0.140, P = 0.163, urge sensation, r = - 0.090, P = 0.375, and maximum tolerable volumes, r = - 0.091, P = 0.366), or when taking age and sex into account. The findings for the patient group were congruent with those for the control group.

CONCLUSIONS

Participants with increased rectal volumes do not experience increased rectal pressures at any sensation level. This finding, combined with the knowledge that rectal pressure triggers rectal filling sensation, indicates that rectal filling sensations in patients with increased rectal volumes are not diminished. Therefore, "rectal hyposensitivity" should be reserved for patients with increased rectal pressure thresholds, and not for "abnormally" increased rectal volume thresholds.

High-resolution anorectal manometry in children with functional constipation: a single-centre experience before and after treatment

INTRODUCTION

Constipation is a common disorder among children, and most of the cases are functional in aetiology. Few studies have reported the manometric data of normal and constipated children.

AIM

To evaluate the manometric parameters in children with functional constipation and to assess any possible changes in these parameters after treatment.

MATERIAL AND METHODS

A prospective descriptive study was conducted at a single centre, enrolling 50 children diagnosed with functional constipation based on Rome IV criteria. Their age ranged from 6 to 14 years with a mean of 7.31 ±1.72 years. High-resolution manometry was performed on all children at the initial presentation and after six months of treatment.

RESULTS

The studied children showed markedly abnormal rectal sensation parameters (increased first sensation, first urge, intense urge, and maximum tolerable volume) during rectal balloon distension. These parameters were even higher in children with stool incontinence (p = 0.005). Manometric data after 6 months of treatment showed that the resting and squeeze pressures were increased when compared to pre-treatment recordings; however, both were statistically insignificant (p = 0.474 and p = 0.155, respectively). Abnormalities in rectal sensations and the manometric parameters reached near normal values following treatment.

CONCLUSIONS

Anorectal manometry is sensitive in predicting improvement in patient condition even before complete clinical cure, and it has a prognostic role in the management of childhood constipation. More research is still needed before recommending anorectal manometry as a routine diagnostic or prognostic tool in paediatric constipation management.

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.

Brain processing of rectal sensation in adolescents with functional defecation disorders and healthy controls

BACKGROUND

Decreased sensation of urge to defecate is often reported by children with functional constipation (FC) and functional nonretentive fecal incontinence (FNRFI). The aim of this cross-sectional study was to evaluate cerebral activity in response to rectal distension in adolescents with FC and FNRFI compared with healthy controls (HCs).

METHODS

We included 15 adolescents with FC, 10 adolescents with FNRFI, and 15 young adult HCs. Rectal barostat was performed prior to functional magnetic resonance imaging (fMRI) to determine individual pressure thresholds for urge sensation. Subjects received 2 sessions of 5 × 30 seconds of barostat stimulation during the acquisition of blood oxygenation level-dependent fMRI. Functional magnetic resonance imaging signal differences were analyzed using SPM8 in Matlab.

KEY RESULTS

Functional constipation and FNRFI patients had higher thresholds for urgency than HCs (P < .001). During rectal distension, FC patients showed activation in the anterior cingulate cortex, dorsolateral prefrontal cortex, inferior parietal lobule, and putamen. No activations were observed in controls and FNRFI patients. Functional nonretentive fecal incontinence patients showed deactivation in the hippocampus, parahippocampal gyrus, fusiform gyrus (FFG), lingual gyrus, posterior parietal cortex, and precentral gyrus. In HCs, deactivated areas were detected in the hippocampus, amygdala, FFG, insula, thalamus, precuneus, and primary somatosensory cortex. In contrast, no regions with significant deactivation were detected in FC patients.

CONCLUSIONS & INFERENCES

Children with FC differ from children with FNRFI and HCs with respect to patterns of cerebral activation and deactivation during rectal distension. Functional nonretentive fecal incontinence patients seem to resemble HCs when it comes to brain processing of rectal distension.

Segmental colonic dilation is associated with premature termination of high-amplitude propagating contractions in children with intractable functional constipation

BACKGROUND

Colonic dilation is common in children with intractable functional constipation (FC). Our aim was to describe the association between segmental colonic dilation and colonic dysmotility in children with FC.

METHODS

We performed a retrospective study on 30 children with intractable FC (according to the Rome III criteria) who had undergone colonic manometry and contrast enema within a 12-month time period. Colonic diameter was measured at 5 cm intervals from the anal verge up to the splenic flexure. Moreover, the distance between the lateral margins of the pedicles of vertebra L2 was measured to provide a ratio (colonic diameter or length/distance between the lateral margins; "standardized colon size" [SCS]). All manometry recordings were visually inspected for the presence of high-amplitude propagating contractions (HAPCs); a parameter for colonic motility integrity. The intracolonic location of the manometry catheter sensors was assessed using an abdominal X-ray.

KEY RESULTS

Colonic segments with HAPCs had a significantly smaller median diameter than colonic segments without HAPCs (4.08 cm vs 5.48 cm, P<.001; SCS 1.14 vs 1.66, P=.001). Children with prematurely terminating HAPCs had significantly larger SCS ratios for colonic diameter than children with fully propagating HAPCs (P=.008). SCS ratios for the length of the rectosigmoid and the descending colon and the SCS ratio for sigmoid colon diameter were significantly larger in children with FC compared to a previously described normative population (P<.0001, P<.0001 and P=.0007 respectively).

CONCLUSIONS & INFERENCES

Segmental colonic dilation was associated with prematurely terminating HAPCs and may be a useful indicator of colonic dysmotility.

Rectal motility in pediatric constipation

OBJECTIVES

Constipation is a common disorder in children, but little is known about its etiology. Rectal impedance planimetry determines segmental rectal cross-sectional area (CSA) and pressure, allowing detailed description of rectal motility. The aim of the present study was to compare rectal motility in healthy and constipated children.

METHODS

We analyzed data from 10 children (1 girl) with constipation according to the Rome III criteria, mean age 8.8 years (standard deviation ± 1.2), and 10 healthy children (5 girls), mean age 9.9 years (standard deviation ± 1.5). CSA was determined at 3 levels (4, 5.5, and 7 cm from the anal verge). The resting rectal motility was recorded for 30 minutes followed by a distension protocol to assess compliance. Runs of phasic rectal contractions were defined as changes of >10% from baseline CSA and lasting at least 2 minutes. Rectal dimensions were expressed as mean CSA.

RESULTS

A low-amplitude contraction pattern (3%-5% of baseline CSA) with a frequency of 6 to 8/minute was present in all of the children. There was significantly more time with phasic rectal contractions in constipated children (median 38%, range [0-100]) compared with healthy children (median 8.8%, range [0-57]) (P < 0.05). The rectal CSA was higher in constipated children (median 1802 mm [range 1106-2948]) compared with healthy children (1375 mm [range 437-1861]) (P < 0.05), but compliance did not differ (constipated: median 38 mm/H2O [range 12-86] vs healthy 33 mm/H2O [range 10-63]) (P = 30).

CONCLUSIONS

In children with constipation, we found phasic rectal contractions for a significantly longer period compared with healthy children, and their rectum is larger than normal.

The use of abdominal muscle training, breathing exercises and abdominal massage to treat paediatric chronic functional constipation

AIM

The effect of muscular training, abdominal massage and diaphragmatic breathing was compared with medical treatment in a prospective randomized trial of patients with chronic functional constipation.

METHOD

Patients aged 4-18 years old with functional constipation according to the Rome III criteria were randomized to physiotherapy or medical treatment. In the physiotherapy group, exercises (isometric training of the abdominal muscles, diaphragmatic breathing exercises and abdominal massage) were employed during 12 40-min sessions twice a week by a trained physiotherapist, with laxatives. Patients in the medication group were only given laxatives. Primary outcome measures were frequency of defaecation and faecal incontinence. The analysis was performed by intention-to-treat.

RESULTS

After 6 weeks of treatment, the frequency of bowel movements was higher in the physiotherapy group [5.1 (2.1) days/week] than in the medication group [3.9 (2.0) days/week] (P = 0.01). The frequency of faecal incontinence was no different between the groups [3.6 (1.9) days/week vs 3.0 (2.1) days/week] (P = 0.31).

CONCLUSION

The combined use of isometric training of abdominal muscles, breathing exercises and abdominal massage increased defaecation frequency after 6 weeks but faecal incontinence remained unchanged. Physiotherapy may be a useful treatment for constipation.

Rectal hyposensitivity

Impaired or blunted rectal sensation, termed rectal hyposensitivity (RH), which is defined clinically as elevated sensory thresholds to rectal balloon distension, is associated with disorders of hindgut function, characterised primarily by symptoms of constipation and fecal incontinence. However, its role in symptom generation and the pathogenetic mechanisms underlying the sensory dysfunction remain incompletely understood, although there is evidence that RH may be due to 'primary' disruption of the afferent pathway, 'secondary' to abnormal rectal biomechanics, or to both. Nevertheless, correction of RH by various interventions (behavioural, neuromodulation, surgical) is associated with, and may be responsible for, symptomatic improvement. This review provides a contemporary overview of RH, focusing on diagnosis, clinical associations, pathophysiology, and treatment paradigms.

The physiology of human defecation

Human defecation involves integrated and coordinated sensorimotor functions, orchestrated by central, spinal, peripheral (somatic and visceral), and enteric neural activities, acting on a morphologically intact gastrointestinal tract (including the final common path, the pelvic floor, and anal sphincters). The multiple factors that ultimately result in defecation are best appreciated by describing four temporally and physiologically fairly distinct phases. This article details our current understanding of normal defecation, including recent advances, but importantly identifies those areas where knowledge or consensus is still lacking. Appreciation of normal physiology is central to directed treatment of constipation and also of fecal incontinence, which are prevalent in the general population and cause significant morbidity.

Sigmoid compliance and visceral perception in spinal cord injury patients

Intestinal motor and sensory dysfunctions in traumatic complete or incomplete spinal cord injury (SCI) are frequent and result in altered mechanisms of defecation. The aim of this study is to investigate sigmoid compliance and perception in chronic SCI patients. Sigmoid responses to fixed-tension distentions were assessed using a tensostat in six patients (six men, 42 ± 4 years) with chronic complete transection of the spinal cord (high-SCI; five tetraplegic C5-C7 and one paraplegic T4-T6) and impaired evacuation (i.e. constipation). A group of 10 healthy individuals (six men, 25 ± 1 years) served as controls. SCI patients had higher sigmoid compliance at the highest distention level than the controls (10.3 ± 2.4 vs. 5.1 ± 0.8 ml/mmHg; P<0.05). Perception scores at first sensation were higher in SCI patients (2.3 ± 0.7 vs. 1.1 ± 0.1; P<0.05), but were not different at the highest distention levels (3.7 ± 0.8 vs. 3 ± 1; NS). The most commonly reported sensation by patients was distention/bloating and was referred less commonly to the hypogastrium compared with distention/bloating in controls. An increased sigmoid compliance can be detected in constipated SCI patients. The preservation of some degree of visceral sensations, although abnormally referred, could imply the occurrence of sensory input remodeling at the spinal level.

Rectal sensorimotor dysfunction in constipation

The pathophysiological mechanisms underlying chronic constipation in both adults and children remain to be unravelled. This is a not inconsiderable challenge, but is fundamental to improving management of such patients. Rectal sensorimotor function, which encompasses both sensation and motility, as well as biomechanical components (compliance, capacity), is now strongly implicated in the pathogenesis of constipation. Rectal hyposensitivity, rectal hypercompliance, increased rectal capacity, rectal motor dysfunction (phasic contractility and tone), and altered rectoanal reflex activity are all found in constipated patients, particularly in association with 'functional' disorders of defaecation (i.e. pelvic floor dyssynergia). This review covers contemporary understanding of how components of rectal sensorimotor function may contribute to symptom development in both adult and paediatric populations. The complex interaction between sensory/motor/biomechanical domains, and how best to measure these functions are addressed, and where data exist, the impact of sensorimotor dysfunction on therapeutic outcomes is highlighted.

No change in rectal sensitivity after gut-directed hypnotherapy in children with functional abdominal pain or irritable bowel syndrome

OBJECTIVES

Gut-directed hypnotherapy (HT) has recently been shown to be highly effective in treating children with functional abdominal pain (FAP) and irritable bowel syndrome (IBS). This study was conducted to determine the extent to which this treatment success is because of an improvement in rectal sensitivity.

METHODS

A total of 46 patients (aged 8-18 years) with FAP (n=28) or IBS (n=18) were randomized to either 12 weeks of standard medical therapy (SMT) or HT. To assess rectal sensitivity, a pressure-controlled intermittent distension protocol (barostat) was performed before and after the therapy.

RESULTS

Rectal sensitivity scores changed in SMT patients from 15.1+/-7.3 mm Hg at baseline to 18.6+/-8.5 mm Hg after 12 weeks of treatment (P=0.09) and in HT patients from 17.0+/-9.2 mm Hg to 22.5+/-10.1 mm Hg (P=0.09). The number of patients with rectal hypersensitivity decreased from 6 of 18 to 0 of 18 in the HT group (P=0.04) vs. 6 of 20 to 4 of 20 in the SMT group (P=0.67). No relationship was established between treatment success and rectal pain thresholds. Rectal sensitivity scores at baseline were not correlated with intensity, frequency, or duration of abdominal pain.

CONCLUSIONS

Clinical success achieved with HT cannot be explained by improvement in rectal sensitivity. Furthermore, no association could be found between rectal barostat findings and clinical symptoms in children with FAP or IBS. Further studies are necessary to shed more light on both the role of rectal sensitivity in pediatric FAP and IBS and the mechanisms by which hypnotherapy results in improvement of clinical symptoms.

Antegrade colonic enemas and intestinal diversion are highly effective in the management of children with intractable constipation

PURPOSE

Intractable constipation in children is an uncommon but debilitating condition. When medical therapy fails, surgery is warranted; but the optimal surgical approach has not been clearly defined. We reviewed our experience with operative management of intractable constipation to identify predictors of success and to compare outcomes after 3 surgical approaches: antegrade continence enema (ACE), enteral diversion, and primary resection.

METHODS

A retrospective review of pediatric patients undergoing ACE, diversion, or resection for intractable, idiopathic constipation from 1994 to 2007 was performed. Satisfactory outcome was defined as minimal fecal soiling and passage of stool at least every other day (ACE, resection) or functional enterostomy without abdominal distension (diversion).

RESULTS

Forty-four patients (range = 1-26 years, mean = 9 years) were included. Sixteen patients underwent ACE, 19 underwent primary diversion (5 ileostomy, 14 colostomy), and 9 had primary colonic resections. Satisfactory outcomes were achieved in 63%, 95%, and 22%, respectively. Of the 19 patients diverted, 14 had intestinal continuity reestablished at a mean of 27 months postdiversion, with all of these having a satisfactory outcome at an average follow-up of 56 months. Five patients underwent closure of the enterostomy without resection, whereas the remainder underwent resection of dysmotile colon based on preoperative colonic manometry studies. Of those undergoing ACE procedures, age younger than 12 years was a predictor of success, whereas preoperative colonic manometry was not predictive of outcome. Second manometry 1 year post-ACE showed improvement in all patients tested. On retrospective review, patient noncompliance contributed to ACE failure.

CONCLUSIONS

Antegrade continence enema and enteral diversion are very effective initial procedures in the management of intractable constipation. Greater than 90% of diverted patients have an excellent outcome after the eventual restoration of intestinal continuity. Colon resection should not be offered as initial therapy, as it is associated with nearly 80% failure rate and the frequent need for additional surgery.

Pathophysiology of evacuation disorders

This review details our contemporary knowledge of the mechanisms underlying evacuatory disorders. There is confusion concerning terminology and classification, which is based upon both an incomplete understanding of the multiple mechanisms involved in evacuation, and that current tests to investigate it are not physiological. Nevertheless, despite the need for more research, significant advances have been made and current assessments can direct therapy.

No role for increased rectal compliance in pediatric functional constipation

BACKGROUND & AIMS

Increased rectal compliance has been proposed to contribute to pediatric functional constipation (FC). We evaluated the clinical relevance of increased rectal compliance and assessed whether regular use of enemas improves rectal compliance in children with FC.

METHODS

A prospective longitudinal study was conducted on children (8-18 years old) with FC. Pressure-controlled rectal distensions were performed at baseline and at 1 year. Rectal compliance was categorized into 3 groups: normal, moderately increased, or severely increased. Patients were randomly assigned to groups given conventional therapy or rectal enemas and conventional therapy. Clinical success was defined as >or=3 spontaneous defecations per week and fecal incontinence <1 per week.

RESULTS

Baseline measurements were performed in 101 children (11.0 +/- 2.1 years); rectal compliance was normal in 36%, moderately increased in 40%, and severely increased in 24%. Patients with severely increased rectal compliance had lower defecation frequency (P = .03), more fecal incontinence (P = .04), and more rectal fecal impaction (P < .001). After 1 year, success values were similar between groups: 42% normal, 41% moderately increased, and 40% with severely increased compliance. Barostat studies performed after 1 year in 80 children (37 conventional therapy and 43 rectal enemas in addition to conventional therapy) revealed that rectal compliance had not changed in either group and had not improved in successfully treated patients.

CONCLUSIONS

Constipated children with severely increased rectal compliance have severe symptoms. However, increased rectal compliance is not related to treatment failure. Regular use of enemas to avoid rectal fecal impaction does not improve rectal compliance in pediatric FC.

A randomized controlled trial of enemas in combination with oral laxative therapy for children with chronic constipation

BACKGROUND & AIMS

After 5 years of intensive oral laxative use, up to 30% of constipated children still have an unsuccessful outcome. Children refractory to oral laxatives might benefit from regular rectal evacuation by enemas. This randomized controlled trial compared the effects of additional treatment with rectal enemas (intervention) with conventional treatment alone (oral laxatives, control) in severely constipated children.

METHODS

In a tertiary hospital in the Netherlands, 100 children, aged 8-18 years, with functional constipation for at least 2 years were randomly assigned to intervention or control groups. The control group received education, behavioral strategies, and oral laxatives. The intervention group was also given 3 rectal enemas/week, reduced by 1 enema/week every 3 months. Outcome measures were defecation and fecal incontinence frequency and overall success at 12, 26, 39, and 52 weeks. Overall success was defined as 3 or more defecations/week and less than 1 fecal incontinence episode/week, irrespective of laxative use.

RESULTS

Defecation frequency normalized in both groups but was significantly higher in the intervention group compared with controls at 26 and 52 weeks (5.6 vs 3.9/week, P = .02, and 5.3 vs 3.9/week, P = .02, respectively). There were no significant differences between groups in reduction of fecal incontinence episodes (P = .49) and overall success rates (P = .67). After 1 year of treatment, the overall success rate was 47.1% in the intervention group versus 36.1% in the control group.

CONCLUSIONS

There is no additional effect of enemas compared with oral laxatives alone as maintenance therapy for severely constipated children.

The effects of butyrate enemas on visceral perception in healthy volunteers

Fermentation of dietary fibres by colonic microbes leads to the production of short chain fatty acids (mainly propionate, butyrate and acetate), which are utilized by the colonic mucosa. Previous studies showed positive effects of butyrate on parameters of oxidative stress, inflammation and apoptosis. Recent studies in rats, however, showed that butyrate increased visceral sensitivity. The aim of this study was to determine the effects of physiologically relevant concentrations of butyrate on visceral perception in healthy human subjects. Eleven healthy volunteers participated in this randomized double-blind, placebo controlled cross-over study. The study consisted of three periods of 1 week each, in which the volunteers daily self-administered rectal enemas containing 100, 50 mmol L(-1) butyrate, or placebo (saline) prior to sleeping. A rectal barostat measurement was performed at the start and the end of each test period for the measurement of pain, urge and discomfort. Butyrate treatment resulted in a dose-dependent reduction of pain, urge and discomfort throughout the entire pressure range of the protocol. At a pressure of 4 mmHg, 50 and 100 mmol L(-1) butyrate concentrations resulted in a 23.9% and 42.1% reduction of pain scores, respectively, and the discomfort scores decreased by 44.2% and 69.0% respectively. At a pressure of 67 mmHg, 50 and 100 mmol L(-1) of butyrate decreased the pain scores by 23.8% and 42%, respectively, and discomfort scores 1.9% and 5.2% respectively. Colonic administration of butyrate, at physiologically relevant concentrations, dose-dependently decreases visceral sensitivity in healthy volunteers.

Pediatric anorectal disorders

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