An increased rectal maximum tolerable volume and long anal canal are associated with poor short-term response to biofeedback therapy for patients with anismus with decreased bowel frequency and normal colonic transit time

Clinical Impact of Rectal Hyposensitivity: A Cross-Sectional Study of 2,876 Patients With Refractory Functional Constipation

INTRODUCTION

Normal bowel function requires intact sensory pathways. Diminished rectal sensation (rectal hyposensitivity [RH]) is associated with constipation, although its clinical importance remains unclear.

METHODS

Consecutive patients (aged 18-80) attending a tertiary center (2004-2016) for investigation of refractory functional constipation (Rome IV core criteria defined, applied post hoc) were included. Patients completed a clinical symptom questionnaire and underwent anorectal physiologic investigations, including rectal sensory testing (balloon distension) to determine 3 well-established sensory thresholds. Multivariate regression analyses were performed to evaluate associations between RH, symptomology, and allied physiologic investigations.

RESULTS

Of 2,876 patients meeting inclusion criteria, 722 (25%) had RH based on ≥1 elevated sensory thresholds (0: n = 2,154 [74.9%]; 1: n = 327 [11.4%]; 2: n = 209 [7.3%]; and 3: n = 186 [6.5%]). A linear relationship existed between increasing number of elevated sensory thresholds and constipation severity (Cleveland Clinic constipation score: mean difference per threshold [95% confidence interval] 0.69 [0.48-0.90]; P < 0.001). Several symptoms were significantly (P < 0.05) associated with RH including: infrequent defecation (odds ratio 1.29 [1.17-1.42]), painful evacuation (1.15 [1.05-1.27]), prolonged toileting (1.14 [1.05-1.24]), and digitation or enema use (1.18 [1.08-1.30]). On defecography, a "functional" evacuation disorder was also associated with RH (1.37 [1.25-1.50], P < 0.001), as was megarectum (2.52 [2.08-3.05], P < 0.001).

DISCUSSION

RH occurs in 25% of patients with refractory functional constipation. Increased number of elevated sensory thresholds is associated with more severe constipation phenotype. These data, in the largest study to date, provide for the first time evidence to show that RH is a major pathophysiologic mechanism in constipation, with recognized clinical impact (http://links.lww.com/AJG/B765).(Equation is included in full-text article.).

Functional anal canal length measurement using high-resolution anorectal manometry to investigate anal sphincter dysfunction in patients with fecal incontinence or constipation

BACKGROUND

Using high-resolution anorectal manometry, we aimed to evaluate the: (a) optimal threshold to measure functional anal canal length (FACL) with intra- and inter-observer variability; (b) relationship between abnormal FACL and other phenotypic findings; and (c) utility of FACL measurement to discriminate between healthy volunteers (HV) and patients with fecal incontinence (FI) or chronic constipation (CC).

METHODS

Consecutive patients referred for investigation of FI or CC in isolation were included. FACL was calculated at 5, 10, 20, 30, and 50 mm Hg above rectal pressure. 5th-95th percentile in HV defined limits of normality.

KEY RESULTS

FACL was analyzed in 192 patients with FI (154 females), 204 patients with CC (175 females), and 134 HV (101 females). The optimal threshold for measurement of FACL was 20 mm Hg. Using this threshold, observer reproducibility was very high (ICC 0.99, P < 0.0001). FACL was shorter in females with FI and longer in females with CC compared to HV (2.3 vs 2.9 cm; and 3.4 cm vs 2.9 cm; both P < 0.0001). Twenty percent of females and 13% males with FI had a short FACL, associated with older age, anal hypotonia or hypocontractility, and a atrophic internal anal sphincter. However, abnormal FACL in isolation was only found in 1/190 FI (0.5%) and 2/201 CC (1%) patients; all other patients had other abnormal manometric findings.

CONCLUSIONS AND INFERENCES

Considering overlap with other routinely evaluated manometric parameters, FACL measurement does not provide additional information in the diagnostic assessment of FI or CC.

An investigation into the effect of biofeedback on urinary and fecal incontinence in patients with anal sphincter dysfunction

Introduction:

Fecal incontinence refers to the inability to control bowel movements, causing feces to leak unexpectedly from the rectum. People suffering from this disorder are emotionally distressed. This problem causes social degradation, anxiety, fear, and social isolation. The present study aimed to evaluate the effect of biofeedback (BFB) on fecal incontinence in patients with anal sphincter abnormalities in 2017.

Methods:

This quasi-experimental study was performed on 30 patients with fecal incontinence, referring to the gastroenterology clinic of Taleghani and Mehrad hospitals. Patients were first evaluated by Wexner criteria and then, with the aid of a manometer, information was obtained on the amount of sphincter muscle tone, squeeze pressure, and rectal sensation. Manometric results and Waxner's questionnaire were compared before and after BFB. Data were analyzed using SPSS (version 20).

Findings:

In this study, 18 women and 12 men were studied. There was no significant relationship between fluid intake, fiber, exercise, sex, and incontinence (P < 0.05). According to Wuxner's components, the sphincter muscle tone increased significantly after BFB in patients. The total score of the squeeze pressure increased significantly after the BFB application (P < 0.05). The mean total score of rectal sensation (individual awareness of rectal contents) decreased after the BFB application.

Conclusion:

In addition to the fact that it can improve incontinence in patients with anal sphincter abnormalities, BFB is also helpful for patients whose sphincter and rectum are not seriously affected and only show incontinence symptoms.

Expert consensus document: Advances in the evaluation of anorectal function

Faecal incontinence and evacuation disorders are common, impair quality of life and incur substantial economic costs worldwide. As symptoms alone are poor predictors of underlying pathophysiology and aetiology, diagnostic tests of anorectal function could facilitate patient management in those cases that are refractory to conservative therapies. In the past decade, several major technological advances have improved our understanding of anorectal structure, coordination and sensorimotor function. This Consensus Statement provides the reader with an appraisal of the current indications, study performance characteristics, clinical utility, strengths and limitations of the most widely available tests of anorectal structure (ultrasonography and MRI) and function (anorectal manometry, neurophysiological investigations, rectal distension techniques and tests of evacuation, including defecography). Additionally, this article provides our consensus on the clinical relevance of these tests.

Efficacy and safety of botulinum toxin in treatment of anismus: A systematic review

AIM: To evaluate the efficacy and safety of botulinum toxin type A (BTX-A) in the management of patients with anismus.

METHODS: An organized search of published literature was conducted using electronic databases including: PubMed/MEDLINE, and Cochrane Central Register of Controlled Trials, also an internet-based search using “Google Scholar” service was conducted. Both comparative and observational studies were included. We excluded irrelevant articles, editorials, case reports, reviews, and meta-analyses. The studies that followed the patients less than 6 mo were excluded. Variables collected were demographic data of the patients, technique of BTX-A injection and number of sessions, short-term and long-term clinical improvement, post-injection changes in electromyography (EMG), defecography, manometry, and balloon expulsion test, and complications recorded after BTX-A injection.

RESULTS: Seven studies comprising 189 patients were included in the review. The median age of the patients was 41.2 years and female-to-male ratio was 1.3:1. The median dose of BTX-A injected per procedure was 100 IU (range, 20-100 IU). Lateral injection was done in five trails and combined lateral and posterior injections in two trials. Three studies used endorectal ultrasonography-guided technique, one study used EMG-guided technique, whereas the remaining three studies used manual palpation with the index finger. The median percentage of patients who reported initial improvement of symptoms was 77.4% (range 37.5%-86.7%), this percentage declined to a median of 46% (range 25%-100%) at 4 mo after injection of BTX-A. Rates of improvement evaluated by balloon expulsion test, EMG, and defecography ranged between (37.5%-80%), (54%-86.7%), and (25%-86.6%), respectively. Fourteen (7.4%) patients developed complications after injection of BTX-A. Complication rates across the studies ranged from 0% to 22.6%.

CONCLUSION: Initial satisfactory improvement of symptoms after BTX-A injection remarkably deteriorated after 3 mo of the procedure. However, repeated injection may provide better sustained results with no additional morbidities. Further analysis of more patients is necessary to conclude the safety of BTX-A for the treatment of anismus.

Long-term efficacy of biofeedback therapy in patients with dyssynergic defecation: results of a median 44 months follow-up

BACKGROUND

The beneficial effect of biofeedback therapy (BFT) over a period of more than 2 years has not been studied in a large group of patients. The aim of this study was to evaluate the long-term efficacy of BFT for dyssynergic defecation (DD).

METHODS

We evaluated the results for 347 consecutive constipated patients with DD who underwent BFT for a median of five sessions between 2004 and 2009. Initial responses were assessed immediately after the completion of BFT. A responder was defined as a subject with at least a three-point improvement from before to after BFT on an 11-point global bowel satisfaction (GBS) scale, or a two-point improvement if the baseline GBS was more than six points. The probability of remaining a responder was estimated by non-parametric maximum likelihood estimation.

KEY RESULTS

The initial response rate to BFT was 72.3% (n = 251), Parkinson's disease and higher baseline GBS scores were associated with initial non-response. The long-term efficacy of BFT was analyzed in 103 patients who were followed up for more than 6 months; the initial effects of BFT were maintained in 85 of the patients (82.5%) during a median of 44 months of follow-up (IQR = 12-68). The probability of remaining a responder was 60% at 2 years, and 58% at 5 years.

CONCLUSIONS & INFERENCES

The efficacy of BFT is maintained for more than 2 years after BFT in a considerable proportion of constipated patients with DD. BFT is effective and durable treatment for managing DD.

Biofeedback for treatment of chronic idiopathic constipation in adults

BACKGROUND

Biofeedback therapy has been used to treat the symptoms of people with chronic constipation referred to specialist services within secondary and tertiary care settings. However, different methods of biofeedback are used within different centres and the magnitude of suggested benefits and comparable effectiveness of different methods of biofeedback has yet to be established.

OBJECTIVES

To determine the efficacy and safety of biofeedback for the treatment of chronic idiopathic (functional) constipation in adults.

SEARCH METHODS

We searched the following databases from inception to 16 December 2013: CENTRAL, the Cochrane Complementary Medicine Field, the Cochrane IBD/FBD Review Group Specialized Register, MEDLINE, EMBASE, CINAHL, British Nursing Index, and PsychINFO. Hand searching of conference proceedings and the reference lists of relevant articles was also undertaken.

SELECTION CRITERIA

All randomised trials evaluating biofeedback in adults with chronic idiopathic constipation were considered for inclusion.

DATA COLLECTION AND ANALYSIS

The primary outcome was global or clinical improvement as defined by the included studies. Secondary outcomes included quality of life, and adverse events as defined by the included studies. Where possible, we calculated the risk ratio (RR) and corresponding 95% confidence interval (CI) for dichotomous outcomes and the mean difference (MD) and 95% CI for continuous outcomes. We assessed the methodological quality of included studies using the Cochrane risk of bias tool. The overall quality of the evidence supporting each outcome was assessed using the GRADE criteria.

MAIN RESULTS

Seventeen eligible studies were identified with a total of 931 participants. Most participants had chronic constipation and dyssynergic defecation. Sixteen of the trials were at high risk of bias for blinding. Attrition bias (4 trials) and other potential bias (5 trials) was also noted. Due to differences between study populations, the heterogeneity of the different samples and large range of different outcome measures, meta-analysis was not possible. Different effect sizes were reported ranging from 40 to 100% of patients who received biofeedback improving following the intervention. While electromyograph (EMG) biofeedback was the most commonly used, there is a lack of evidence as to whether any one method of biofeedback is more effective than any other method of biofeedback. We found low or very low quality evidence that biofeedback is superior to oral diazepam, sham biofeedback and laxatives. One study (n = 60) found EMG biofeedback to be superior to oral diazepam. Seventy per cent (21/30) of biofeedback patients had improved constipation at three month follow-up compared to 23% (7/30) of diazepam patients (RR 3.00, 95% CI 1.51 to 5.98). One study compared manometry biofeedback to sham biofeedback or standard therapy consisting of diet, exercise and laxatives. The mean number of complete spontaneous bowel movements (CSBM) per week at three months was 4.6 in the biofeedback group compared to 2.8 in the sham biofeedback group (MD 1.80, 95% CI 1.25 to 2.35; 52 patients). The mean number of CSBM per week at three months was 4.6 in the biofeedback group compared to 1.9 in the standard care group (MD 2.70, 95% CI 1.99 to 3.41; 49 patients). Another study (n = 109) compared EMG biofeedback to conventional treatment with laxatives and dietary and lifestyle advice. This study found that at both 6 and 12 months 80% (43/54) of biofeedback patients reported clinical improvement compared to 22% (12/55) laxative-treated patients (RR 3.65, 95% CI 2.17 to 6.13). Some surgical procedures (partial division of puborectalis and stapled transanal rectal resection (STARR)) were reported to be superior to biofeedback, although with a high risk of adverse events in the surgical groups (wound infection, faecal incontinence, pain, and bleeding that required further surgical intervention). Successful treatment, defined as a decrease in the obstructed defecation score of > 50% at one year was reported in 33% (3/39) of EMG biofeedback patients compared to 82% (44/54) of STARR patients (RR 0.41, 95% CI 0.26 to 0.65). For the other study the mean constipation score at one year was 16.1 in the balloon sensory biofeedback group compared to 10.5 in the partial division of puborectalis surgery group (MD 5.60, 95% CI 4.67 to 6.53; 40 patients). Another study (n = 60) found no significant difference in efficacy did not demonstrate the superiority of a surgical intervention (posterior myomectomy of internal anal sphincter and puborectalis) over biofeedback. Conflicting results were found regarding the comparative effectiveness of biofeedback and botulinum toxin-A. One small study (48 participants) suggested that botulinum toxin-A injection may have short term benefits over biofeedback, but the relative effects of treatments were uncertain at one year follow-up. No adverse events were reported for biofeedback, although this was not specifically reported in the majority of studies. The results of all of these studies need to be interpreted with caution as GRADE analyses rated the overall quality of the evidence for the primary outcomes (i.e. clinical or global improvement as defined by the studies) as low or very low due to high risk of bias (i.e. open label studies, self-selection bias, incomplete outcome data, and baseline imbalance) and imprecision (i.e. sparse data).

AUTHORS' CONCLUSIONS

Currently there is insufficient evidence to allow any firm conclusions regarding the efficacy and safety of biofeedback for the management of people with chronic constipation. We found low or very low quality evidence from single studies to support the effectiveness of biofeedback for the management of people with chronic constipation and dyssynergic defecation. However, the majority of trials are of poor methodological quality and subject to bias. Further well-designed randomised controlled trials with adequate sample sizes, validated outcome measures (especially patient reported outcome measures) and long-term follow-up are required to allow definitive conclusions to be drawn.

Prospective randomized double-blind study of temporary sacral nerve stimulation in patients with rectal evacuatory dysfunction and rectal hyposensitivity

OBJECTIVE

Prospective randomized double-blind placebo-controlled crossover trial of 14 female patients (median age 52 [30-69] years) with proctographically defined evacuatory dysfunction (ED) and demonstrable rectal hyposensitivity (elevated thresholds to balloon distension in comparison with age- and sex-matched controls).

BACKGROUND

Sacral nerve stimulation (SNS) is an evolving treatment for constipation. However, variable outcomes might be improved by better patient selection. Evidence that the effect of SNS may be mediated by modulation of afferent signaling promotes a role in patients with ED associated with rectal hyposensation.

METHODS

SNS was performed by the standard 2-stage technique (temporary then permanent implantation). During a 4-week period of temporary stimulation, patients were randomized ON-OFF/OFF-ON for two 2-week periods. Before insertion (PRE), and during each crossover period, primary (rectal sensory thresholds) and secondary (bowel diaries, constipation, and GIQoL [gastrointestinal quality of life] scores) outcome variables were blindly assessed.

RESULTS

Thirteen patients completed the trial. Following stimulation, defecatory desire volumes to rectal balloon distension were normalized in 10 of 13 patients (PRE: mean 277 mL [234-320] vs ON: 163 mL [133-193] vs OFF: 220 mL [183-257 mL]; P = 0.006) and maximum tolerable volume in 9 of 13 (PRE: mean 350 mL [323-377] vs ON: 262 mL [219-305] vs OFF: 298 mL [256-340 mL]; P = 0.012). There was a significant increase in the percentage of successful bowel movements (PRE: median 43% [0-100] vs ON: 89% [11-100] vs OFF: 83% [11-100]; P = 0.007) and Wexner constipation scores improved (PRE: median 19 [9-26] vs ON: 10 [6-27] vs OFF: 13 [5-29]; P = 0.01). There were no significant changes in disease-specific or generic quality of life measures. Eleven patients progressed to permanent stimulation (9/11 success at 19 months).

CONCLUSIONS

Most patients with chronic constipation secondary to ED with rectal hyposensitivity responded to temporary SNS. The physiological results presented support a mechanistic role for rectal afferent modulation.

Excellent response rate of anismus to botulinum toxin if rectal prolapse misdiagnosed as anismus ('pseudoanismus') is excluded

AIM

Anismus causes obstructed defecation as a result of inappropriate contraction of the puborectalis/external sphincter. Proctographic failure to empty after 30 s is used as a simple surrogate for simultaneous electromyography/proctography. Botulinum toxin is theoretically attractive but efficacy is variable. We aimed to evaluate the efficacy of botulinum toxin to treat obstructed defecation caused by anismus.

METHOD

Botulinum toxin was administered, under local anaesthetic, into the puborectalis/external sphincter of patients with proctographic anismus. Responders (resolution followed by recurrence of obstructed defecation over a 1- to 2-month period) underwent repeat injection. Nonresponders underwent rectal examination under anaesthetic (EUA). EUA-diagnosed rectal prolapse was graded using the Oxford Prolapse Grade 1-5.

RESULTS

Fifty-six patients were treated with botulinum toxin. Twenty-two (39%) responded initially and 21/22 (95%) underwent repeat treatment. At a median follow up of 19.2 (range, 7.0-30.4) months, 20/21 (95%) had a sustained response and required no further treatment. Isolated obstructed defecation symptoms (OR = 7.8, P = 0.008), but not proctographic or physiological factors, predicted response on logistic regression analysis. In 33 (97%) of 34 nonresponders, significant abnormalities were demonstrated at EUA: 31 (94%) had a grade 3-5 rectal prolapse, one had internal anal sphincter myopathy and one had a fissure. Exclusion of these alternative diagnoses revised the initial response rate to 96%.

CONCLUSION

Simple proctographic criteria overdiagnose anismus and underdiagnose rectal prolapse. This explains the published variable response to botulinum toxin. Failure to respond should prompt EUA seeking undiagnosed rectal prolapse. A response to an initial dose of botulinum toxin might be considered a more reliable diagnosis of anismus than proctography.

Comparative study between surgical and non-surgical treatment of anismus in patients with symptoms of obstructed defecation: a prospective randomized study

PURPOSE

This study came to compare the results of biofeedback retraining biofeedback (BFB), botulinum toxin botulinum type A (BTX-A) injection and partial division of puborectalis (PDPR) in the treatment of anismus patients.

PATIENTS AND METHODS

Consecutive patients treated for anismus fulfilled Rome II criteria for functional constipation at our institution were evaluated for inclusion. Participants were randomly allocated to receive BFB, BTX-A injection, and PDPR. All patients underwent anorectal manometry, balloon expulsion test, defecography, and electromyography activity of the anal sphincter. Follow up was conducted weekly in the first month then monthly for about 1 year. Study variables included clinical improvement, patient satisfaction, and objective improvement.

RESULTS

Sixty patients with anismus were randomized and completed the study. The groups differed significantly regarding clinical improvement at 1 month (50% for BFB, 75%BTX-A injection, and 95% for PDPR, P = 0.006) and differences persisted at 1 year (30% for BFB, 35%BTX-A injection, and 70% for PDPR, P = 0.02). Constipation score of the patients significantly improved postPDPR and BTX-A injection. Manometric relaxation was achieved significantly in the three groups.

CONCLUSION

Biofeedback retraining has a limited therapeutic effect, BTX-A injection seems to be successful for temporary treatment but PDPR is found to be an effective with lower morbidity in contrast to its higher success rate in treating anismus.

Predictive capability of anorectal physiologic tests for unfavorable outcomes following biofeedback therapy in dyssynergic defecation

The purpose of this study is to evaluate the predictive capability of anorectal physiologic tests for unfavorable outcomes prior to the initiation of biofeedback therapy in patients with dyssynergic defecation. We analyzed a total of 80 consecutive patients who received biofeedback therapy for chronic idiopathic functional constipation with dyssynergic defecation. After classifying the patients into two groups (responders and non-responders), univariate and multivariate analyses were performed to determine the predictors associated with the responsiveness to biofeedback therapy. Of the 80 patients, 63 (78.7%) responded to biofeedback therapy and 17 (21.3%) did not. On univariate analysis, the inability to evacuate an intrarectal balloon (P=0.028), higher rectal volume for first, urgent, and maximal sensation (P=0.023, P=0.008, P=0.007, respectively), and increased anorectal angle during squeeze (P=0.020) were associated with poor outcomes. On multivariate analysis, the inability to evacuate an intrarectal balloon (P=0.018) and increased anorectal angle during squeeze (P=0.029) were both found to be independently associated with a lack of response to biofeedback therapy. Our data show that the two anorectal physiologic test factors are associated with poor response to biofeedback therapy for patients with dyssynergic defecation. These findings may assist physicians in predicting the responsiveness to therapy for this patient population.

Discriminative value of anorectal manometry in clinical practice

Guidelines recommend anorectal manometry in patients with fecal incontinence and chronic constipation. However, limited evidence supports the utility of manometric testing. We retrospectively reviewed tracings obtained between November 2005 and May 2008. A total of 298 patients (86% women; average age 52 years) were included. The main indications were incontinence (51%) and constipation (42%). Patients suffering from incontinence were older and had lower resting and squeeze pressure compared to continent patients. However, the discriminative power of manometric pressure data was poor, with low sensitivity and specificity. An abnormal straining pattern suggesting dyssynergic defecation was seen in 43% of constipated patients compared to 13% of patients with fecal incontinence. A concordance between manometric patterns and the balloon expulsion test was seen in 72%. The low sensitivity and specificity of manometric parameters does not support the routine use of anorectal manometry in patients with defecation disorders.

Physiological, psychological and behavioural characteristics of men and women with faecal incontinence

BACKGROUND

The factors leading to faecal incontinence in males are less well understood than those in females. In this prospective study we aimed to compare the physiological, anatomical, psychological and behavioural characteristics of male and female patients presenting with symptoms of faecal incontinence.

METHOD

One hundred and nine patients presenting with symptoms of faecal incontinence were studied. They underwent anorectal physiological studies, endoanal ultrasonography, and completed a St Mark's Incontinence Score, a locally developed pad questionnaire, a bowel symptom questionnaire, the Short Form 36 (SF-36) Health Survey questionnaire, the Hospital Anxiety and Depression Scale and the Maudsley Obsessive Compulsive Inventory.

RESULTS

Thirty-four men (mean age 59 years, SD 14 years, range 33-80) and 75 women (mean age 55 years, SD 15 years, range 21-86) participated in the study. Twenty-one patients (38% of men and 11% of women) had normal manometry and endoanal ultrasonography. There was no significant difference in the resting pressures of men compared with women, but men had significantly higher squeeze pressures. Rectal capacity was significantly higher in men but anal and rectal electrosensitivities were the same. Men placed a tissue at the anus more commonly than women while women were more likely to use a pad and to carry a spare pair of underwear around with them. Psychological profiles were very similar in the two sexes.

CONCLUSIONS

Nearly 40% of men with faecal incontinence report it in the absence of a definable functional or structural sphincter abnormality. There are differences in physiological characteristics and coping behaviours of men and women with faecal incontinence.

Idiopathic proximal hemimegacolon: radiologic findings and analyses of clinical and physiological characteristics

BACKGROUND

Idiopathic megacolon with bowel dilatation only proximal to the splenic flexure is an uncommon and poorly characterized disease. This study aimed to identify the characteristics of idiopathic proximal hemimegacolon.

METHODS

Five patients (2 males and 3 females) were diagnosed to have idiopathic proximal hemimegacolon and their radiologic, clinical, and physiological characteristics were reviewed. Hirschsprung's disease and other known causes of bowel dilatation were excluded by the presence of rectoanal inhibitory reflex and reviewing medical records.

RESULTS

Mean age at diagnosis and symptom onset were 50.4 years and 47.2 years, respectively. Four patients presented with constipation, and all five patients showed abdominal distention and abdominal pain. Four patients were successfully treated and maintained only with laxatives and prokinetics without enema. Only one patient underwent surgery for intractable constipation. Mean maximal diameters of each segment of colons measured by computed tomography were 57.5 mm, 69.3 mm, 73.0 mm, 33.3 mm, 24.0 mm, and 27.3 mm for cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum, respectively. Colon transit time was delayed in four patients with mean value of 90.0 h.

CONCLUSIONS

These results indicated that patients with idiopathic proximal hemimegacolon may be treated successfully only with medical therapy in most cases.

Comparative study between biofeedback retraining and botulinum neurotoxin in the treatment of anismus patients

PURPOSE

Anismus is a significant cause of chronic constipation. This study came to revive the results of BFB training and BTX-A injection in the treatment of anismus patients.

MATERIALS AND METHODS

Forty-eight patients with anismus (33 women; mean age 39.6 +/- 15.9) were included in this study. All patients fulfilled Rome II criteria for functional constipation. All patients underwent anorectal manometry, balloon expulsion test, defecography, and electromyography (EMG) activity of the EAS. All patients had non-relaxing puborectalis muscle. The patients were randomized into two groups. Group I patients received biofeedback therapy, two times per week for about 1 month. Group II patients were injected with BTX-A. Follow-up was conducted weekly in the first month then monthly for about 1 year.

RESULTS

In the BFB training group, three patients quit before the end of sessions with no improvement; initial improvement was recorded in 12 patients (50%) while long-term success was recorded in six patients (25%). In the BTX-A group, clinical improvement was recorded in 17 patients (70.83%), but the improvement persisted only in eight patients (33.3%). There is a significant difference between BTX-A group and BFB group regarding the initial success, but this significant difference disappeared at the end of follow-up. Manometric relaxation was achieved significantly post-BFB and post-BTX-A injection with no significant difference between the two groups.

CONCLUSIONS

Biofeedback training has a limited therapeutic effect on patients suffering from anismus. BTX-A injection seems to be successful for temporary treatment of anismus.

Enteroendocrine cell counts correlate with visceral hypersensitivity in patients with diarrhoea-predominant irritable bowel syndrome

The objective of this study was to determine whether or not the number of enteroendocrine cells (ECs) in the gut is related to visceral hypersensitivity in patients with diarrhoea-predominant irritable bowel syndrome (D-IBS). Twenty-five subjects with D-IBS (mean, 43.1 years; 16 women, nine men) were recruited into our study, along with 13 healthy controls (mean, 40.7 years; nine women, four men). Maximally tolerable pressures were evaluated via barostat testing, and the levels of ECs were immunohistochemically identified and quantified via image analysis. The numbers of ECs between the D-IBS subjects and the controls were not significantly different in the terminal ileum, ascending colon and rectum. However, the maximally tolerable pressures determined in the D-IBS subjects were significantly lower than those of the control subjects (P < 0.01), and we detected a significant relationship between the maximally tolerable pressures and the numbers of ECs in the rectum (r = -0.37, P < 0.01). Rectal sensitivity was enhanced to a greater degree in D-IBS patients exhibiting an elevated level of rectal ECs. This study provides some evidence to suggest that ECs play an important role in visceral hypersensitivity.

Mucosal mast cell counts correlate with visceral hypersensitivity in patients with diarrhea predominant irritable bowel syndrome

BACKGROUND AND AIM

Although increased mast cells in the gut and their role in visceral hypersensitivity in irritable bowel syndrome have been postulated, this relationship remains unclear. Our aim was to determine whether a relationship exists between the number of mucosal mast cells in the gut and visceral hypersensitivity.

METHOD

Eighteen patients with diarrhea predominant irritable bowel syndrome (D-IBS) (eight females, 10 males aged 25-65 years; mean 42.6 years) with symptoms meeting the Rome-II criteria, and 15 healthy controls (five females, 10 males aged 31-57 years; mean 41.4 years) were recruited. Participants completed a questionnaire for bowel symptoms and psychological distress. Colonic mucosal mast cells were identified immunohistochemically and quantified by image analysis, and maximally tolerable pressures were evaluated using barostat test.

RESULTS

Numbers of mast cells were significantly greater in the terminal ileum, ascending colon and rectum of D-IBS patients compared with controls (P<0.01). A multivariate analysis of the barostat test showed that maximally tolerable pressures of D-IBS patients were significantly lower than those of controls (P<0.01). When patients were divided into the rectal hypersensitivity (+) and (-) groups by the distension level of 34 mmHg, mast cell counts were significantly higher in the rectal hypersensitivity (-) group than in the rectal hypersensitivity (+) group for the terminal ileum, ascending colon and rectum (P<0.05, respectively).

CONCLUSIONS

Rectal sensitivity was enhanced in D-IBS patients with moderately increased mucosal mast cells, but it was attenuated in patients with markedly increased ones. This study might provide evidence for an important role of mast cells in visceral hypersensitivity.

Increased beta-adrenergic sensitivity correlates with visceral hypersensitivity in patients with constipation-predominant irritable bowel syndrome

Autonomic imbalance has been proposed to be a pathophysiological factor for irritable bowel syndrome (IBS). The aim of this study was to assess beta-adrenergic abnormalities in IBS and to evaluate their relationship to visceral hypersensitivity and other symptoms of IBS patients. Sixteen IBS patients and 16 control subjects were recruited into this study. Participants were asked to complete a questionnaire regarding bowel symptoms, and in order to study beta-adrenergic sensitivity, isoproterenol stimulation tests were performed and visceral hypersensitivity was evaluated by barostat test. Results showed that beta-adrenergic activity and rectal sensitivity were more pronounced in IBS patients than in normal control patients (P < 0.01). Although both IBS subgroups also exhibited more pronounced beta-adrenergic sensitivity than did the controls (P < 0.05), a significant correlation between beta-adrenergic activity and maximally tolerable pressures on the barostat test was found only in IBS-C patients (P = 0.03, R = 0.855). In addition, patients with "hard or lumpy" stools exhibited a higher degree of beta-adrenergic activity (P = 0.00). We conclude that increased beta-adrenergic activity significantly correlated with visceral hypersensitivity in constipation-predominant IBS and symptoms of hard or lumpy stools in IBS patients.

Treatment of obstructed defecation

Obstructed defecation is a common problem that adversely affects the quality of life for many patients. Known causes of obstructed defecation include pelvic dyssynergy, rectocele, rectal intussusception, enterocele, pelvic organ prolapse, and overt rectal prolapse. Management of this condition requires an understanding of urinary, defecatory, and sexual function to achieve optimal outcomes. The goal of surgical treatment is to restore the various pelvic organs to their appropriate anatomic positions. However, there is a poor correlation between anatomic and functional results. It must be remembered that the pelvis contains many structures and that defects of pelvic support or function frequently affect other pelvic organs. Optimal outcomes can be achieved only by selecting appropriate treatment modalities that address all of the components of an individual patient's problem.

Responses of anal constipation to biofeedback treatment

OBJECTIVE

Biofeedback is considered an effective treatment for anal constipation, but a substantial proportion of patients fail to improve. Our aim was to identify the key predictors of outcome using a comprehensive standardized evaluation of anorectal function.

MATERIAL AND METHODS

We retrospectively analysed the clinical and physiological data of 148 patients consecutively treated for constipation due to functional outlet obstruction by biofeedback. Clinical evaluation was performed by means of a structured questionnaire. Anorectal evaluation included anal pressure, neural reflexes, defecatory dynamics, rectal compliance, rectal sensitivity and balloon expulsion test. Biofeedback treatment was performed using a manometric technique. The clinical response to biofeedback treatment was evaluated as good (improvement of constipation) or poor (no improvement or worsening).

RESULTS

Of the 148 patients included, 112 (86 F, 26 M; age range 8-67 years) were followed-up for between 1 and 44 months, and 66% had a good response to treatment. The response depended on the severity of the defecatory dysfunction. Thus, lack of anal relaxation during straining and inability to evacuate a 1 ml intrarectal balloon were inversely related to physiological variables related to therapeutic success. Among the 49 patients with absent anal relaxation, 51% had a good response to treatment (versus 78% in patients with partial relaxation; p < 0.01), and among the 29 patients with failed balloon expulsion, 48% responded to treatment (versus 74% in patients able to evacuate > or = 1 ml intrarectal balloon; p < 0.05).

CONCLUSIONS

Even in the presence of negative predictors, biofeedback is a valuable treatment option in a substantial proportion of constipated patients.

Constipation caused by functional outlet obstruction

Functional constipation is a very common problem in Western societies. Functional outlet obstruction, part of the spectrum of functional constipation, is suspected when patients present with select symptoms. Diagnosis is commonly made with anorectal manometry, electromyography, and rectal evacuation tests. Abnormal test patterns include poor relaxation and contraction of the anal sphincter in response to attempted defecation and difficult rectal evacuation. Several treatment approaches have been tested in these patients. Biofeedback training is considered the most specific therapeutic modality, and it is particularly attractive because of its safety. This review provides an assessment of the diagnostic tests for functional outlet obstruction and summarizes current options for therapy.