High-resolution anorectal manometry: A comparison of solid-state and water-perfused catheters

London Protocol under water-perfused HRM in a healthy population, towards novel 3D manometric parameters in an evaluation of anorectal functional disorders

BACKGROUND/AIM

London Protocol (LP) and Classification allied to high-resolution manometry (HRM) technological evolution has updated and enhanced the diagnostic armamentarium in anorectal disorders. This study aims to evaluate LP reproducibility under water-perfused HRM, provide normal data and new parameters based on 3D and healthy comparison studies under perfusional HRM.

METHODS

Fifty healthy (25 F) underwent water-perfused 36 channel HRM based on LP at resting, squeeze, cough, push, and rectal sensory. Additional 3D manometric parameters were: pressure-volume (PV) 104mmHg2.cm (resting, short and long squeeze, cough); highest and lowest pressure asymmetry (resting, short squeeze, and cough). Complementary parameters (CP) were: resting (mean pressure, functional anal canal length); short squeeze (mean and maximum absolute squeeze pressure), endurance (fatigue rate, fatigue rate index, capacity to sustain); cough (anorectal gradient pressure); push (rectum-anal gradient pressure, anal canal relaxation percent); recto-anal inhibitory reflex (anal canal relaxation percent).

RESULTS

No difference to genders: resting (LP, CP, and 3D); short squeeze (highest pressure asymmetry); endurance (CP); cough (CP, highest and lowest pressure asymmetry); push (gradient pressure); rectal sensory. Higher pressure in men: short squeeze (maximum incremental, absolute, and mean pressure, PV, lowest pressure asymmetry); long squeeze (PV); cough (anal canal and rectum maximum pressure, anal canal PV); push (anal canal and rectum maximum pressure). Anal canal relaxation was higher in women (push).

CONCLUSIONS

LP reproducibility is feasible under water-perfused HRM, and comparative studies could bring similarity to dataset expansion. Novel 3D parameters need further studies with healthy and larger data to be validated and for disease comparisons.

KEY POINTS

• London Protocol and Classification allied with the technological evolution of HRM (software and probes) has refined the diagnostic armamentarium in anorectal disorders. • Novel 3D and deepening the analysis of manometric parameters before the London Classification as a contributory diagnostic tool. • Comparison of healthy volunteers according to the London Protocol under a perfusional high-resolution system could establish equivalence points.

Role of 3D high resolution anorectal manometry compared to conventional technique in management of constipation and fecal incontinence in children

BACKGROUND

Anorectal manometry is a valuable tool for objective assessment of motility motor and sensory function of the anorectum. The aim of this study was to investigate role of water-perfused (WP) three dimensional high-resolution anorectal manometry (3D-HRARM) compared to WP conventional manometry (CM) in the management of chronic idiopathic constipation (CIC) and faecal incontinence (FI) in children.

METHODS

This was a retrospective review of 122 consecutive children, who had WP 8-channel CM or 24 channel 3D-HRARM and endosonography under ketamine anaesthesia from September 2012 to February 2019. All patients had a validated symptom severity score questionnaire ranging from 0 (best) to 65 (worst). Mann-Whitney-U test and Spearman rank test were used and p<0.05 was considered significant.

RESULTS

Subjects were divided according to investigation: CM group (n = 75) and 3D-HRAM (n = 47), who were otherwise comparable. Median anal resting pressure was 50 mmHg and rectoanal inhibitory reflex (RAIR) threshold volume was 10mls across the entire cohort. There were no significant differences in resting pressure or RAIR threshold when using conventional or 3D-HRARM. Rectal capacity was significantly higher in the CM group (p = 0.002). Rectal capacity and internal anal sphincter (IAS) thickness positively correlated with symptom severity, duration and patient age. 3D-HRARM provided a more detailed depiction of the anorectal pressure profile. Botulinum toxin was injected into the external anal sphincter (EAS) muscle (n = 75, 61%) and an anterograde colonic enema (ACE) stoma was needed subsequently in 19 (16%) to treat recurrent constipation and soiling symptoms. Rectal biopsy was done in 43(35%) patients, if RAIR was absent or inconclusive.

CONCLUSION

CM and 3D-HRARM are comparable in terms of resting pressure and RAIR threshold. 3D-HRAM is safe and provides detailed functional morphology of anal sphincters and it is useful to understand underlying pathophysiology of constipation and faecal incontinence in children and plan further treatment.

LEVEL OF EVIDENCE

Level I.

Effects of Aging and Gender on the Anorectal Function of Healthy Subjects Assessed with Conventional Anorectal Manometry

Background/Aims

Anorectal functions are influenced by gender and age. This study sought to define the normal anorectal pressure values measured with conventional anorectal manometry (ARM) and to evaluate the effects of age and gender on anorectal function in asymptomatic subjects.

Methods

Conventional ARM was used to measure the anorectal pressures of 164 asymptomatic healthy subjects, including 86 males and 76 females.

Results

The resting anal pressures of males and females aged >60 years were significantly lower than those ≤60 years (males, 44.09±14.22 vs. 57.45±17.69, p<0.001; females, 44.09±14.22 vs. 57.45±17.69, p<0.001). The anal high-pressure zone was significantly lower in older males than in younger males (2.42±0.93 vs. 2.82±0.739, p=0.048). In both age groups (<60 and ≥60 years), the anal squeezing pressures of males were significantly higher than those of females (<60 years old, 168.40±75.94 vs. 119.15±57.53, p=0.001; ≥60 years, 149.61±64.68 vs. 101.3±54.92, p=0.006).

Conclusions

The normal anorectal pressure values measured with ARM in males and females were different. Older males and females had lower anal resting pressures than those of the younger subjects, but squeezing pressure was not affected by age.

Slow, deep breathing intervention improved symptoms and altered rectal sensitivity in patients with constipation-predominant irritable bowel syndrome

BACKGROUND AND AIM

Limited treatment options have been shown to alter the natural course of irritable bowel syndrome (IBS). Slow, deep breathing (SDB) is a common pain self-management intervention. This pilot study aimed to explore the impact of SDB on measures of autonomic and anorectal functions as well as patient-reported symptoms in constipation-predominant IBS (IBS-C).

METHODS

Eighty-five IBS-C patients were enrolled in this study and randomly assigned to the experimental group (Group A, n = 42) and the control group (Group B, n = 43). SDB was conducted at six breathing cycles per minute with an inhalation for 4 s and exhalation for 6 s at a ratio of 2:3 and repeated for 30 min during the intervention. All subjects underwent high-resolution anorectal manometry (HRAM) and completed the standardized IBS symptom severity system (IBS-SSS) questionnaire. Meanwhile, changes in stool consistency, weekly frequency of complete spontaneous bowel movements (CSBMs), and weekly frequency of spontaneous bowel movements (SBMs) were recorded. All IBS-C patients received electrocardiogram (ECG) recordings for heart rate variability (HRV) analysis at baseline, weeks 3, 6.

RESULTS

At baseline, no differences were found between Groups A and B. The IBS-SSS score and its five sub-scores of Group B patients were significantly higher at week 6 than those of Group A patients (all p < 0.001). Furthermore, compared with Group B patients, Group A patients had a significantly higher threshold volume for the first sensation (p < 0.001), desire to defecate (p = 0.017), and maximum tolerable volume (p = 0.018) at week 6 of the SDB treatment. We also noted significant improvements in stool consistency (p = 0.002), weekly SBM frequencies (p < 0.001), and weekly CSBM frequencies (p = 0.018) of Group A patients at week 6 when compared with Group B patients. Finally, the corrected high frequency (HF) of Group A patients was significantly higher than the HF of Group B patients at week 3 (p < 0.001) and at week 6 (p < 0.001). Likewise, patients in Group A had a significantly higher root mean square of the successive differences (RMSSD) than that of patients in Group B at week 3 (p < 0.001) and at week 6 (p < 0.001).

CONCLUSION

We found that a 6-week SDB intervention improved symptoms and altered rectal sensation in IBS-C patients. Moreover, SDB enhanced vagal activity. These findings suggest that the effect of SDB on IBS-C may be due to mechanisms involving autonomic responses.

Review of the indications, methods, and clinical utility of anorectal manometry and the rectal balloon expulsion test

BACKGROUND

Anorectal manometry (ARM) comprehensively assesses anorectal sensorimotor functions.

PURPOSE

This review examines the indications, techniques, interpretation, strengths, and weaknesses of high-resolution ARM (HR-ARM), 3-dimensional high-resolution anorectal manometry (3D-HR-ARM), and portable ARM, and other assessments (i.e., rectal sensation and rectal balloon expulsion test) that are performed alongside manometry. It is based on a literature search of articles related to ARM in adults. HR-ARM and 3D-HR-ARM are useful for diagnosing defecatory disorders (DD), to identify anorectal sensorimotor dysfunction and guide management in patients with fecal incontinence (FI), constipation, megacolon, and megarectum; and to screen for anorectal structural (e.g., rectal intussusception) abnormalities. The rectal balloon expulsion test is a useful, low-cost, radiation-free, outpatient assessment tool for impaired evacuation that is performed and interpreted in conjunction with ARM. The anorectal function tests should be interpreted with reference to age- and sex-matched normal values, clinical features, and results of other tests. A larger database of technique-specific normal values and newer paradigms of analyzing anorectal pressure profiles will increase the precision and diagnostic utility of HR-ARM for identifying abnormal mechanisms of defecation and continence.

Intra- and inter-observer agreement in the classification of dyssynergic defecation on high-resolution anorectal manometry using water-perfusion system

BACKGROUND AND AIMS

Dyssynergic defecation (DD) classified on anorectal manometry is based on variations in anal sphincter pressures and rectal pressure generated during bearing down. There is a paucity of data on intra- and inter-observer agreement in the classification of DD on high-resolution anorectal manometry (HRAM) using a water-perfusion system.

METHODS

This cross-sectional observational study was conducted between June 2014 and May 2016 on 70 adult patients with DD. Observer 1 did the baseline analysis and reanalyzed the readings at least 6 months later, blinded to the initial analysis results (intra-observer variability). Four other blinded observers (5-25 years in anorectal manometry and minimum 5 years of experience in HRAM) then individually analyzed the manometry data (inter-observer variability).

RESULTS

Intra-observer agreement was excellent (kappa 0.862) for classifying DD. Agreement between the six observations (i.e. two from observer 1 and four from independent observers) was also good (kappa 0.632). The highest agreement was for type 4 DD (kappa 0.738), followed by type 1 (0.680), type 2 (0.664), and type 3 (0.537). Cronbach's alpha value was 0.93, suggesting excellent internal consistency.

CONCLUSION

The diagnosis of the types of DD on anorectal manometry using a water-perfusion system has excellent intra-observer and good inter-observer agreement .

Sleep Deficiency Is Associated With Exacerbation of Symptoms and Impairment of Anorectal and Autonomic Functions in Patients With Functional Constipation

Objective

Sleep deficiency (SD) is commonly seen in patients with functional constipation (FC). Our aim was to determine whether the presence of SD would influence symptoms, anorectal motility, sensation, and autonomic function in FC patients.

Materials and Methods

A total of 85 FC patients with SD and 193 FC patients without SD underwent high-resolution anorectal manometry. SD was assessed by using the Pittsburgh Sleep Quality Index (PSQI) score. Participants were required to fill in the entire questionnaires, including Patients’ Constipation-symptoms, State-Trait Anxiety Inventory, and Hamilton Depression Scale. Autonomic dysfunction was studied by recording the heart rate variability. Multiple logistic regression was performed to explore the potential risk factors for anorectal function.

Results

Functional constipation patients with SD had a higher total score of constipation symptom (P &lt; 0.001), in comparison with those without SD. FC patients with SD demonstrated significantly lower threshold volume for first sensation (P &lt; 0.001) and urge (P &lt; 0.001), as compared to those without SD. The PSQI score positively correlated with constipation symptom total score (P &lt; 0.001), and negatively correlated with threshold volume for first sensation (P &lt; 0.001) and urge (P &lt; 0.001). FC patients with SD had a reduced vagal activity (P = 0.016) and a higher sympathetic activity as compared to those without SD (P = 0.003). Multivariate logistic regression revealed that SD, anxiety and depression were independent risk factors for anorectal function, with SD exhibiting the highest degree of association with first sensation (OR: 4.235).

Conclusion

Sleep deficiency is associated with worse constipation related symptoms, altered anorectal function and perception, and impaired autonomic function in FC patients.

Prevalence of double incontinence in patients with fecal incontinence undergoing anorectal manometry and discriminating factors

Background: Double incontinence (DI) is the concomitant presence of incontinence for urine and stool. Aim of this study is to assess prevalence of DI in patients with fecal incontinence (FI) undergoing Ano-Rectal Manometry (ARM) in a tertiary care center and to identify factors discriminating between both. Methods: Medical records of consecutive patients referred for ARM for FI during 2 years at University Hospital Brussels were retrospectively reviewed. Results from ARM, presence of diarrhea, diseases from recto-anal or peri-anal region, prior abdominal, proctological or urological surgery and neurological comorbidities were recorded. Results: Of 101 enrolled patients, 77% suffered from solitary FI and 23% from DI. Diarrhea was more common in DI vs. FI (43,5% vs. 15,4%, P=.008), as was the presence of neurological comorbidities (34.8% vs. 10.3%, P=.009) and urological interventions (21.7% vs. 1.3%, P=.002). In respect to women only, more urological interventions were performed (20% vs. 0%, P=.006) and more diseases from recto-anal or peri-anal region were encountered in DI vs. FI (35.0 % vs. 12.5 %, P= .045). In men, neurological disorders were significantly more common in DI (100.0% vs. 3.3%, P=.002). Conclusions: This study identified gender-specific patterns of comorbidities in FI and DI. ARM had no distinctive value between FI and DI in men and women. A prospective study should provide more information on patients at risk for incontinence and help to identify distinct features between FI and DI in men and women.

Evaluation of Anorectal Function in Perianal Crohn's Disease: A Pilot Study

Background: Perianal Crohn’s disease is a disabling condition, with little known about anorectal function in healed/inactive perianal Crohn’s disease; Aim: To evaluate anorectal function in a cohort of patients with treated/healed perianal Crohn’s disease; Methods: Prospective cohort study, including high-resolution anorectal manometry, balloon expulsion test, and 3D-endoanal ultrasound in all patients; Results: Of the 16 patients studied (mean age ± SD, 42 ± 13 years), 12 (75%) were men. A laceration of the internal anal sphincter and/or anal scarring was seen in nine (56%) patients; there was no laceration of the external anal sphincter. Five (56%) of these nine patients had never experienced faecal incontinence. All had normal anal resting and squeeze pressures. Manometry suggested dyssynergia in 11 (69%) patients, with only one (6%) fulfilling the criteria for obstructed defecation. Hyposensitivity for at least one sensory parameter was seen in 11 (69%) patients and hypersensitivity in five (31%) patients; Conclusions: This study detected sphincter abnormalities in more than half of patients, many of whom were asymptomatic. Alterations in rectal sensation were frequently seen, more commonly with rectal hyposensitivity. Trial registration: ClinicalTrials.gov (NCT03819257).

Comparison of Anorectal Function as Measured with High-Resolution and High-Definition Anorectal Manometry

INTRODUCTION

Anorectal manometry (ARM) provides comprehensive assessment of pressure activity in the rectum and anal canal. Absolute pressure values might depend on the catheter used.

OBJECTIVE

Our aim was to compare the results obtained by different anorectal catheters in children with functional anorectal disorders.

METHODS

Children diagnosed with functional defecation disorders based on the Rome IV criteria were prospectively enrolled. ARM was performed in the supine position successively using 2 different probes in each patient in random order. Resting, squeeze pressures, and bear-down maneuver variables obtained by high-resolution (2-dimensional [2D]) and high-definition (3-dimensional [3D]) catheters were compared.

RESULTS

We prospectively included 100 children {mean age 7.5 [standard deviation (SD) ± 4.3] years; 62 boys}. Mean resting pressures were significantly higher when measured with the 3D than with the 2D catheter (71 [SD ± 19.4] vs. 65 [SD ± 20.1] mm Hg, respectively; p = 0.000). Intrarectal pressure measured by 3D and 2D catheters was similar (35 vs. 39 mm Hg, respectively; p = 0.761), but the percent of anal relaxation appeared to be higher for the 3D than for the 2D probe (12 vs. 5%, respectively; p = 0.002). Dyssynergic defecation (DD) was diagnosed in 41/71 patients (57.7%) using the 3D probe and in 51/71 children (71.8%) using the 2D probe (p = 0.044). Cohen's kappa showed only fair agreement between the catheters (κ = 0.40) in diagnosis of DD.

CONCLUSIONS

Our study demonstrated significantly different values of pressures obtained with different types of catheters. Normal ranges for conventional manometry cannot be applied to high-resolution systems, and results obtained by different types of manometry cannot be compared without adjustments (NCT02812823).

Systematic evaluation of cough-anorectal pressure responses in health and in fecal incontinence: A high-resolution anorectal manometry study

BACKGROUND

Anorectal manometry is the most commonly performed test of anorectal function. The cough-anorectal response is frequently assessed as part of a routine manometric investigation but has not previously been the subject of detailed analysis. This study systematically examined anorectal pressure responses to cough in health and evaluated the impact of parity and symptoms of fecal incontinence (FI) on measurements.

METHODS

High-resolution anorectal manometry (HR-ARM) traces from nulliparous (n = 25) and parous (n = 25) healthy volunteers (HV: aged 41, range 18-64), and 57 parous patients with FI (age 47, range 28-72) were retrospectively reviewed. Cough-anorectal pressure responses were analyzed between groups by qualitative and quantitative approaches.

KEY RESULTS

In health, traditional anal pressure measurements ("rest" and "squeeze") were similar between nulliparous and parous women. In contrast, incremental anal-rectal pressure difference during cough significantly differed: nulliparous 42 mm Hg (95% CI: 21-64) vs. parous 6 mm Hg (-14-25), P < 0.036). This measure also differed significantly between nulliparous HVs and patients with FI (-2 mm Hg (95% CI: -15-12), P < 0.001), but not between parous HVs and FI. Qualitatively, a color-contour trace resembling a "spear" in the upper anal canal was observed uniquely in FI. Of 25 patients with normal anal function by traditional measures, cough parameters were abnormal in 52%.

CONCLUSIONS AND INFERENCES

Novel HR-ARM measures during coughing revealed differences in anal function between nulliparous and parous HV, and patients with FI, which were not detected by traditional measures. Cough-anorectal measurements may improve manometric yield, though clinical utility would require assessment by longitudinal studies.

[Recommendations for the Protocol of functional examination of the anorectal zone and disorders classification: the International Anorectal Physiology Working Group consensus and Russian real-world practice]

This manuscript summarizes consensus reached by the International Anorectal Physiology Working Group (IAPWG) for the performance, terminology used, and interpretation of anorectal function testing including anorectal manometry (focused on high-resolution manometry), the rectal sensory test, and the balloon expulsion test. Based on these measurements, a classification system for disorders of anorectal function is proposed. Aim to provide information about methods of diagnosis and new classification of functional anorectal disorders to a wide range of specialists general practitioners, therapists, gastroenterologists, coloproctologists all who face the manifestations of these diseases in everyday practice and determine the diagnostic and therapeutic algorithm. Current paper provides agreed statements of IAPWG Consensus and comments (in italics) of Russian experts on real-world practice, mainly on methodology of examination. These comments in no way intended to detract from the provisions agreed by the international group of experts. We hope that these comments will help to improve the quality of examination based on the systematization of local experience with the use of the methods discussed and the results obtained. Key recommendations: the International Anorectal Physiology Working Group protocol for the performance of anorectal function testing recommends a standardized sequence of maneuvers to test rectoanal reflexes, anal tone and contractility, rectoanal coordination, and rectal sensation. Major findings not seen in healthy controls defined by the classification are as follows: rectoanal areflexia, anal hypotension and hypocontractility, rectal hyposensitivity, and hypersensitivity. Minor and inconclusive findings that can be present in health and require additional information prior to diagnosis include anal hypertension and dyssynergia.

Comparison of anorectal function measured using wearable digital manometry and a high resolution manometry system

There is a need for a lower cost manometry system for assessing anorectal function in primary and secondary care settings. We developed an index finger-based system (termed "digital manometry") and tested it in healthy volunteers, patients with chronic constipation, and fecal incontinence. Anorectal pressures were measured in 16 participants with the digital manometry system and a 23-channel high-resolution anorectal manometry system. The results were compared using a Bland-Altman analysis at rest as well as during maximum squeeze and simulated defecation maneuvers. Myoelectric activity of the puborectalis muscle was also quantified simultaneously using the digital manometry system. The limits of agreement between the two methods were -7.1 ± 25.7 mmHg for anal sphincter resting pressure, 0.4 ± 23.0 mmHg for the anal sphincter pressure change during simulated defecation, -37.6 ± 50.9 mmHg for rectal pressure changes during simulated defecation, and -20.6 ± 172.6 mmHg for anal sphincter pressure during the maximum squeeze maneuver. The change in the puborectalis myoelectric activity was proportional to the anal sphincter pressure increment during a maximum squeeze maneuver (slope = 0.6, R2 = 0.4). Digital manometry provided a similar evaluation of anorectal pressures and puborectalis myoelectric activity at an order of magnitude less cost than high-resolution manometry, and with a similar level of patient comfort. Digital Manometry provides a simple, inexpensive, point of service means of assessing anorectal function in patients with chronic constipation and fecal incontinence.

The London Classification: Improving Characterization and Classification of Anorectal Function with Anorectal Manometry

PURPOSE OF REVIEW

Objective measurement of anorectal sensorimotor function is a requisite component in the clinical evaluation of patients with intractable symptoms of anorectal dysfunction. Regrettably, the utility of the most established and widely employed investigations for such measurement (anorectal manometry (ARM), rectal sensory testing and the balloon expulsion test) has been limited by wide variations in clinical practice.

RECENT FINDINGS

This article summarizes the recently published International Anorectal Physiology Working Group (IAPWG) consensus and London Classification of anorectal disorders, together with relevant allied literature, to provide guidance on the indications for, equipment, protocol, measurement definitions and results interpretation for ARM, rectal sensory testing and the balloon expulsion test. The London Classification is a standardized method and nomenclature for description of alterations in anorectal motor and sensory function using office-based investigations, adoption of which should bring much needed harmonization of practice.

High-resolution anorectal manometry in children with functional constipation with or without fecal incontinence

BACKGROUND

High-resolution anorectal manometry (HR-ARM) is expected to be better than conventional manometry. Our aim was to characterize HR-ARM pressures in children with functional constipation (FC), with or without fecal incontinence (FI).

METHODS

Children with diagnosis of FC, with or without FI, according to Rome-IV criteria, were enrolled. All patients underwent HR-ARM using 24-channel water-perfused catheter.

RESULTS

Twenty-nine consecutive children (M/F: 21/8; mean age ± SD: 9.5 ± 3.1 years; range 4-15), of whom 21 affected by FC without FI (mean age ± SD: 9.3 ± 3.23 years) and 8 affected by FC with FI (mean age ± SD: 10.2 ± 3.08 years), were enrolled. No significant differences were found regard to gender and age. The analysis of HR-ARM 3D plots demonstrated asymmetry of the anal canal, with higher pressures in distal halves. Comparing pressures between the two groups, we found lower values in FC with FI than in FC without FI group, with a statistically significance for maximum and mean resting pressures (P = .032 and P = .008, respectively). When evaluating our study population respect to asymptomatic children, we found lower resting pressures, lower maximum squeeze pressure, and higher rectoanal inhibitory reflex (RAIR) values.

CONCLUSIONS

Our data demonstrate that HR-ARM pressures at rest and during squeezing in FC with FI children are lower than FC without FI subjects, particularly in anteroposterior quadrants. Compared to children without lower gastrointestinal symptoms, children with FC with or without FI show lower pressures and higher values of RAIR.

The relationship between dectin-1 and mast cells in patients with diarrhea-predominant irritable bowel syndrome

Background/Aims: Currently, the role of the microbiome GBA is being widely studied in the pathogenesis of visceral hypersensitivity in IBS. To investigate the role of fungus, the current study aimed to i) investigate the expression of Syk/CARD9-coupled Dectin-1 receptors in the ileocecal mucosa in D-IBS patients and (ii) explore the relationships between Dectin-1 and plasma MCT levels as well as anorectal sensory function in patients with D-IBS.Methods: Thirty-eight D-IBS patients who met the Rome III criteria and 2 groups of age- and sex-matched asymptomatic healthy controls were recruited from March 2015 to January 2017. Anorectal sensory function was quantified by HR-ARM. Plasma MCT titers were identified by ELISA, while the expression of Syk/CARD9 Dectin-1 receptors in ileocecal mucosa was identified by RT-qPCR.Results: (i) The expression of Syk/CARD9-coupled Dectin-1 receptors was significantly higher in D-IBS patients than in controls (p < .001). ii) The threshold values of first sensation and desire to defecate were significantly lower in D-IBS patientsthan in controls (the P value was0.007 and 0.001 respectively). (iii) There were negative correlations between plasma MCT levels and first sensation thresholds in D-IBS patients (r = -0.513, p = .012) and the desire to defecate thresholds (r = -0.423, p = .044). (iiii) There was a positive correlation between plasma MCT titers and the expression of Dectin-1 receptors in D-IBS patients (r = 0.565, p = .005).Conclusions: These results suggested that fungi may partially participate in the genesis of visceral hypersensitivity by activating mast cells, which is mediated by activation of the Dectin-1 receptor-mediated Syk/CARD9 signaling pathway.

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.

High-resolution colonic manometry and its clinical application in patients with colonic dysmotility: A review

The detailed process and mechanism of colonic motility are still unclear, and colonic motility disorders are associated with numerous clinical diseases. Colonic manometry is considered to the most direct means of evaluating colonic peristalsis. Colonic manometry has been studied for more than 30 years; however, the long duration of the examination, high risk of catheterization, huge amount of real-time data, strict catheter sterilization, and high cost of disposable equipment restrict its wide application in clinical practice. Recently, high-resolution colonic manometry (HRCM) has rapidly developed into a major technique for obtaining more effective information involved in the physiology and/or pathophysiology of colonic contractile activity in colonic dysmotility patients. This review focuses on colonic motility, manometry, operation, and motor patterns, and the clinical application of HRCM. Furthermore, the limitations, future directions, and potential usefulness of HRCM in the evaluation of clinical treatment effects are also discussed.

High-resolution anal manometry: Repeatability, validation, and comparison with conventional manometry

BACKGROUND

Accurate measurement of anal sphincter function is potentially of value in defining treatment of common pelvic floor disorders. The aim of this study was to establish repeatability and validate high-resolution anorectal manometry (HRAM) by comparison to conventional manometry (CM). Arising from this work would be definitive normal range data.

METHODS

Eighty healthy volunteers (40 female) underwent a test-retest repeatability study. A 16-channel water-perfused HRAM catheter was compared to an 8-channel conventional catheter using a station pull-through technique.

KEY RESULTS

High-resolution anorectal manometry had similar precision to conventional manometry when measuring resting pressure (intraclass correlation coefficient [ICC] 0.73 vs 0.68, HRAM vs CM) and squeeze increment (ICC 0.90 vs 0.94, HRAM vs CM). HRAM measured resting pressures 10% lower than CM and squeeze pressure 27% higher than CM.

CONCLUSIONS AND INFERENCES

High-resolution anorectal manometry is a valid technique with comparable precision to CM. HRAM measurements differ considerably to CM, and a new set of normal values must be used.

High-resolution and high-definition anorectal manometry: rediscovering anorectal function

Anorectal motor and functional disorders are common among the general population. Anorectal manometry allows the study of anorectal motor activity both at rest and mimicking different physiological situations. High-resolution anorectal manometry (HR-ARM) and high-definition anorectal manometry (HD-ARM) are increasingly used in clinical practice. In comparison with the conventional technique, HR-ARM and HD-ARM catheters provide a higher number of recording points because of their many, closely packed circumferential sensors. This allows time-space visualization (topographic or 2-3-plane mode) as spatially continuous measurements are obtained by interpolation between near sensors. HR-ARM and HD-ARM allow a more standardized, reproducible technique, and a better assessment and understanding of the functional anatomy of the sphincter complex. Newer specific parameters are now being developed for use with these systems. They are being currently assessed by multiple research teams, and many of them remain unavailable for clinical practice as of today. However, they provide highly relevant information, which is now prompting a redefinition of anorectal anatomy and physiology. The goal of the present review was to describe the currently available HR-ARM and HD-ARM techniques, to discuss the normal values so far reported, and to analyze the newer parameters that may be assessed with these techniques, and which will likely be highly useful for clinical practice in the upcoming future.

Evaluation of 153 Asymptomatic Subjects Using the Anopress Portable Anal Manometry Device

Background/Aims

The Anopress device is a new portable manometry system. The aim of this study is to formulate normative data using this new device by recording the anorectal function of asymptomatic subjects. Patient comfort was also assessed.

Methods

Anorectal function was assessed in asymptomatic volunteers using the Anopress. All volunteers were examined in a standardized way in accordance with the study protocol. Normative values for the Anopress were obtained from the recorded data and patient comfort was assessed using a visual analogue scale.

Results

We recruited 153 healthy volunteers. Eighty were female (23 parous; median age 39.5 [interquartile range {IQR}, 28.75–53.00]) and 73 were male (median age 40.5 [IQR, 29.00–52.25]). For the female cohort, the following normal range (2.5–97.5 percentile) values were recorded across the whole anal canal: resting pressure 40.0–103.0 mmHg; squeeze increment 35.0–140.6 mmHg; endurance 1.3–9.0 seconds; involuntary squeeze 41.1–120.8 mmHg; and strain pressure 22.1–77.9 mmHg. Similarly, the following male normal range (2.5–97.5 percentile) values were recorded across the whole anal canal: resting pressure 38.3–99.6 mmHg; squeeze increment 42.5–154.8 mmHg; involuntary squeeze 40.0–123.6 mmHg; endurance 2.0–10.0 seconds; and strain pressure 11.0–72.1 mmHg. The median visual analogue scale scores for discomfort during the measurement was 0.0 (IQR, 0.00–0.00).

Conclusions

Normative values for the Anopress device have been calculated by this study. The Anopress appears to be a safe and well tolerated way of measuring pressures from the entire anal canal. Further comparisons with other standard and commonly used manometry tests are, however, required to verify its reliability.

High-Resolution Anorectal Manometry - New Insights in the Diagnostic Assessment of Functional Anorectal Disorders

Functional anorectal disorders such as faecal incontinence (FI), functional anorectal pain, and functional defecation disorders (FDD) are highly prevalent and represent a high socioeconomic burden. Several tests of anorectal function exist in this setting; however, high-resolution anorectal manometry (HR-ARM) is a new tool that depicts pressure all along the anal canal and can assess rectoanal coordination. HR-ARM is used in the diagnosis of FI and especially FDD although data in health is still sparse, and pressure phenomena seen during simulated defecation, such as dyssynergia, are highly prevalent in health.