Impaired proximal colonic motor response to rectal mechanical and chemical stimulation in obstructed defecation

Diagnosis of colonic dysmotility associated with autonomic dysfunction in patients with chronic refractory constipation

We report the first study assessing human colon manometric features and their correlations with changes in autonomic functioning in patients with refractory chronic constipation prior to consideration of surgical intervention. High-resolution colonic manometry (HRCM) with simultaneous heart rate variability (HRV) was performed in 14 patients, and the resulting features were compared to healthy subjects. Patients were categorized into three groups that had normal, weak, or no high amplitude propagating pressure waves (HAPWs) to any intervention. We found mild vagal pathway impairment presented as lower HAPW amplitude in the proximal colon in response to proximal colon balloon distention. Left colon dysmotility was observed in 71% of patients, with features of (1) less left colon HAPWs, (2) lower left colon HAPW amplitudes (69.8 vs 102.3 mmHg), (3) impaired coloanal coordination, (4) left colon hypertonicity in patients with coccyx injury. Patients showed the following autonomic dysfunction: (1) high sympathetic tone at baseline, (2) high sympathetic reactivity to active standing and meal, (3) correlation of low parasympathetic reactivity to the meal with absence of the coloanal reflex, (4) lower parasympathetic and higher sympathetic activity during occurrence of HAPWs. In conclusion, left colon dysmotility and high sympathetic tone and reactivity, more so than vagal pathway impairment, play important roles in refractory chronic constipation and suggests sacral neuromodulation as a possible treatment.

Rationale and design of a multicenter, single-group, open-label trial aiming at investigating the effectiveness of elobixibat for loss of defecation desire in patients with chronic constipation

Background

Approximately 60% of patients with chronic constipation (CC) have a significantly higher rate of loss of defecation desire (LODD). Bile acids are expected to have a restorative effect on defecation desire (DD) because they lower the rectal sensory threshold, which is an objective index of DD. Elobixibat (EXB) specifically inhibits the ileal bile acid transporter/apical sodium-dependent bile acid transporter, which is a transporter involved in the reabsorption of bile acids in the terminal ileum. This study aims to investigate the LODD improvement rate in patients with CC after 4 weeks of EXB treatment.

Methods

A total of 40 adult patients with CC who meet the eligibility criteria will be enrolled. Patients will receive oral EXB (10 mg/day) for 4 weeks. A patient diary will be provided daily at 4 weeks after treatment. The primary endpoint will be the percentage LODD improvement at week 4 of the treatment period from week 2 of the observation period using questionnaires.

Ethics and dissemination

Ethical approval was obtained from the Yokohama City University Certified Institutional Review Board prior to participant enrolment (approval number: CRB21-008). The results of this study will be submitted for publication in international peer-reviewed journals, and key findings will be presented at international scientific conferences. Participants desiring the results of this study will be directly contacted for data dissemination.

Trial registration

This trial was registered at ClinicalTrials.gov (NCT05165199).

Protocol version

1.0, September 21, 2021.

The Role of Intestinal Permeability in Gastrointestinal Disorders and Current Methods of Evaluation

An increased intestinal permeability has been described in various gastrointestinal and non-gastrointestinal disorders. Nevertheless, the concept and definition of intestinal permeability is relatively broad and includes not only an altered paracellular route, regulated by tight junction proteins, but also the transcellular route involving membrane transporters and channels, and endocytic mechanisms. Paracellular intestinal permeability can be assessed in vivo by using different molecules (e.g., sugars, polyethylene glycols, ⁵¹Cr-EDTA) and ex vivo in Ussing chambers combining electrophysiology and probes of different molecular sizes. The latter is still the gold standard technique for assessing the epithelial barrier function, whereas in vivo techniques, including putative blood biomarkers such as intestinal fatty acid-binding protein and zonulin, are broadly used despite limitations. In the second part of the review, the current evidence of the role of impaired barrier function in the pathophysiology of selected gastrointestinal and liver diseases is discussed. Celiac disease is one of the conditions with the best evidence for impaired barrier function playing a crucial role with zonulin as its proposed regulator. Increased permeability is clearly present in inflammatory bowel disease, but the question of whether this is a primary event or a consequence of inflammation remains unsolved. The gut-liver axis with a crucial role in impaired intestinal barrier function is increasingly recognized in chronic alcoholic and metabolic liver disease. Finally, the current evidence does not support an important role for increased permeability in bile acid diarrhea.

Long-term outcomes and quality of life after subtotal colectomy combined with modified Duhamel procedure for adult Hirschsprung's disease

BACKGROUND

Subtotal colectomy combined with modified Duhamel procedure (Jinling procedure) was used in patients with adult Hirschsprung's disease (AHD) at Jinling Hospital in the last decade. The aim of this study is to evaluate the safety, effectiveness and quality of life of Jinling procedure for AHD.

MATERIALS AND METHODS

All the data are from the database of the Jinling Hospital Constipation Registry System. Primary outcomes, including safety (morbidity and adverse events), effectiveness (satisfaction rate, Wexner constipation scale (WCS) and bowel function score (BFS)) and gastrointestinal quality of life index (GIQLI), were all evaluated.

RESULTS

Fifty-nine patients were available for this study and the mean postoperative period was 44 months. Seventeen major complications were found in 11 patients and most of the complications could be managed conservatively. A significant improvement in WCS, BFS and GIQLI at 6 months postoperatively was obtained.

CONCLUSION

Jinling procedure is safe and effective for AHD.

Colonic electrical stimulation for the treatment of slow-transit constipation: a preliminary pilot study

BACKGROUND

Electrical stimulation of the gastrointestinal tract is an attractive concept. In this article we report on a procedure for electrical colonic pacing due to intramuscular electrode placement for slow-transit constipation and some preliminary results.

METHODS

From January 2011 to December 2012, all consecutive patients affected by constipation and evaluated in our Pelvic Floor Center were prospectively assessed. Patients who underwent colonic electrical stimulation were evaluated for the present study.

RESULTS

In the study period, 256 patients were evaluated for constipation; 58% were identified as having obstructed defecation syndrome, 27.3% with irritable bowel syndrome or mixed forms, 4% with pelvic floor dyssynergia, and 10.5% (27 patients) as having slow-transit constipation. After failure of all the maximal conventional therapies, two patients, candidates for colectomy, agreed to undergo colonic electrical stimulation before a resective treatment. Both patients were females, aged 34 and 29 years, and were suffering from severe constipation since childhood. The follow-up was 19 and 6 months. The number of bowel movements per week increased from 0.3 to 3.5 in the first patient and from 0.5 to 2.5 in the second patient. Both patients no longer needed laxatives, enemas, or any other treatment. The hospital stay was 4 days, the mean operative time was 120 min, and no complications were reported.

CONCLUSIONS

Colonic pacing seems to be feasible and shows positive results. Further studies are required with a larger number of patients and a longer follow-up period to confirm the role of this promising treatment for slow-transit constipation.

Review article: faecal incontinence in children: epidemiology, pathophysiology, clinical evaluation and management

BACKGROUND

Faecal incontinence (FI) in children is a significant gastrointestinal problem, with great personal and social impacts. It is characterised by recurrent loss of faecal matter into the underwear. Both functional and organic causes contribute to its aetiology with the former predominating.

AIM

To review the epidemiology, pathophysiology, clinical evaluation and management of functional faecal incontinence in children.

METHODS

A PubMed search was conducted using search terms f(a)ecal incontinence, and encopresis. Articles on epidemiology, pathophysiology, clinical evaluation, investigation and management of functional FI in children were retrieved and assessed.

RESULTS

Community prevalence of this distressing problem ranges from 0.8% to 7.8% globally. Male: female ratio varies from 3:1 to 6:1. The diagnosis of FI is often based on established clinical criteria. The majority (82%) have constipation associated functional FI. Biopsychosocial factors play a crucial role in the pathogenesis. Limited physiological testing of anorectal function is recommended in the diagnostic procedures, particularly in children with atypical symptoms and possible organic disorders. Management of FI needs a multidisciplinary approach which includes establishment of an effective doctor-patient partnership, understanding the underlying mechanisms, pharmacotherapy and behavioural treatment. Approximately 15% of children with functional nonretentive faecal incontinence (FNRFI) had the same symptoms at the age of 18 years.

CONCLUSION

Significant therapeutic advances have been made for retentive faecal incontinence, but treatment options for functional nonretentive faecal incontinence are limited. Limited long-term outcome data show that the majority outgrow faecal incontinence. A substantial proportion of children progress to adulthood with faecal incontinence.

Long-term follow-up of the Jinling procedure for combined slow-transit constipation and obstructive defecation

BACKGROUND

Surgery is indicated for chronic constipation refractory to conservative therapy. The treatment of combined slow-transit constipation and obstructive defecation is controversial.

OBJECTIVE

The aim of the study is to describe the Jinling procedure and examine safety, effectiveness, and quality of life over 4 years of follow-up.

DESIGN

The study is a retrospective review of prospectively gathered data in a patient registry database.

SETTINGS

This investigation was conducted at a tertiary-care gastroenterology surgical center in China.

PATIENTS

The study included 117 consecutive patients with slow-transit constipation combined with obstructive defecation treated between January 2005 and December 2007.

INTERVENTION

The Jinling procedure modifies the classic procedure of subtotal colectomy with colorectal anastomosis by adding a new side-to-side cecorectal anastomosis to solve the coexistence of obstructive defecation and slow-transit constipation in one operation.

MAIN OUTCOME MEASURES

We measured morbidity and mortality rates, Wexner constipation scores, and Gastrointestinal Quality of Life Index at baseline and after 1, 6, 12, 24, 36 and 48 months of follow-up.

RESULTS

A total of 117 patients underwent the Jinling procedure, which was laparoscopically assisted in 56 patients (47.9%) and an open procedure in 61 patients (52.1%). Of the total, 72 patients (61.5%) had undergone previous surgical intervention without improvement. A total of 28 complications and adverse events were reported in 117 procedures, giving an overall morbidity rate of 23.9%; 23 patients (19.7%) had 1 or more events. Most complications were managed conservatively. A significant reduction in Wexner constipation score was observed from baseline (mean, 21.9) to 1 month (mean, 9.8), and the reduction was maintained at 48 months (mean 5.1; p < 0.001). Compared with baseline, significant overall improvements were also seen in gastrointestinal quality of life at 12, 24, and 48 months of follow-up (p < 0.01).

LIMITATIONS

This study did not include a comparison group.

CONCLUSIONS

Our clinical practice demonstrates that Jinling procedure is safe and effective for refractory slow-transit constipation associated with obstructive defecation, with minimal major complications, significant improvement of quality of life, and a high satisfaction rate after 4-year follow up.

An assessment of enteric nervous system and estroprogestinic receptors in obstructed defecation associated with rectal intussusception

BACKGROUND

The pathophysiological basis of obstructed defecation (OD) is still incompletely understood. In particular, few or no data are available concerning the enteric nervous system (ENS) in this condition. We investigated ENS abnormalities in patients with OD, undergoing surgery, together with the presence of estrogen (α and β) and progesterone receptors, and compare the results with those obtained in controls.

METHODS

Full-thickness rectal samples were obtained from 17 patients undergoing stapled transanal rectal resection for OD associated with rectal intussusception. Samples were analyzed by immunohistochemistry for enteric neurons, enteric glial cells, interstitial cells of Cajal (ICC), and for estrogen and progesterone receptors. Data were compared with those obtained in 10 controls.

KEY RESULTS

No differences between patients and controls were found for enteric neurons, whereas (compared with controls) OD patients displayed a significant decrease of enteric glial cells in both the submucous (P = 0.0006) and the myenteric (P < 0.0001) plexus. ICC were significantly increased in patients in the submucosal surface (P < 0.0001) and the myenteric area (P < 0.0001). Concerning estroprogestinic receptors, both were present on ICC in patients and controls. Estrogen receptors α and progesterone receptors were absent on enteric neurons and enteric glial cells in patients and controls, whereas estrogen receptors β were present in all controls and in 69% of patients' enteric neurons (P = 0.18) and in 12% of patients' glial cells (P = 0.0001).

CONCLUSIONS & INFERENCES

Patients with OD associated to rectal intussusception display abnormalities of the ENS and of estrogen receptors β.

Colonic dysmotility in constipation

Constipation is a common and distressing condition with major morbidity, health care burden, and impact on quality of life. Colonic motor dysfunction remains the leading hypothesis to explain symptom generation in the most severe cases of chronic constipation and physiological testing plays a role in identifying the colonic dysmotility and the subsequent patient management. Measurement of colonic motor patterns and transit has enhanced our knowledge of normal and abnormal colonic motor physiology. The scope of this review encompasses the latest findings that improve our understanding of the motility disorders associated with colonic dysfunction in both the paediatric and adult population suffering from constipation.

Paediatric and adult colonic manometry: A tool to help unravel the pathophysiology of constipation

Colonic motility subserves large bowel functions, including absorption, storage, propulsion and defaecation. Colonic motor dysfunction remains the leading hypothesis to explain symptom generation in chronic constipation, a heterogeneous condition which is extremely prevalent in the general population, and has huge socioeconomic impact and individual suffering. Physiological testing plays a crucial role in patient management, as it is now accepted that symptom-based assessment, although important, is unsatisfactory as the sole means of directing therapy. Colonic manometry provides a direct method for studying motor activities of the large bowel, and this review provides a contemporary understanding of how this technique has enhanced our knowledge of normal colonic motor physiology, as well as helping to elucidate pathophysiological mechanisms underlying constipation. Methodological approaches, including available catheter types, placement technique and recording protocols, are covered, along with a detailed description of recorded colonic motor activities. This review also critically examines the role of colonic manometry in current clinical practice, and how manometric assessment may aid diagnosis, classification and guide therapeutic intervention in the constipated individual. Most importantly, this review considers both adult and paediatric patients. Limitations of the procedure and a look to the future are also addressed.

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.

Pathophysiology of colonic causes of chronic constipation

Colonic sensorimotor dysfunction is recognized as the principal pathophysiological mechanism underpinning chronic constipation. This review addresses current understanding derived from both human and animal studies, with particular reference made to methods of investigation.

Spatio-temporal analysis reveals aberrant linkage among sequential propagating pressure wave sequences in patients with symptomatically defined obstructed defecation

Available evidence implicates abnormal colonic contractility in patients suffering from constipation. Traditional analysis of colonic manometry focuses on the frequency, extent and amplitude of propagating sequences (PS). We tested the hypotheses that the spatio-temporal linkage among sequential PSs exists throughout the healthy human colon and is disrupted during constipation. In eight patients with severe constipation and eight healthy volunteers, we recorded colonic pressures from 16 regions (caecum-rectum) for 24 h. Sequential PSs were regionally linked if the two PSs originated from different colonic regions but the segments of colon traversed by each PS overlapped. In order to determine whether this linkage occurred by chance, a computer program was used to randomly rearrange all PSs in time. Data were re-analysed to compare regional linkage between randomly re-ordered PSs (expected) and the natural distribution of PSs (observed). In controls the observed regional linkage (82.5 +/- 9.0%) was significantly greater than the expected value (60.5 +/- 4.3%; P = 0.0001). In patients the observed and expected regional linkage did not differ. The (observed - expected) delta value of regional linkage in controls was significantly greater than in patients (21.7 +/- 8.5%vs-2.3 +/- 7.0%; P = 0.01). Regional linkage among sequential PSs in the healthy colon appears to be a real phenomenon and this linkage is lost in patients with constipation. Regional linkage may be important for normal colonic transit and loss of linkage might have pathophysiological relevance to and provide a useful biomarker of severe constipation.

Twenty-four hour spatiotemporal mapping of colonic propagating sequences provides pathophysiological insight into constipation

Colonic propagating sequences (PS)s are a major determinant of luminal propulsion. A global appreciation of spatiotemporal patterning of PSs requires evaluation of 24 h pan-colonic recordings, a difficult task given that PSs are relatively infrequent events that are not uniformly distributed throughout the colon. Here we developed a means of space-time-pressure 'mapping' in a condensed format, 24 h of colonic recording in such a manner that readily permits an overall view of colonic antegrade and retrograde colonic PSs within a single figure. Such graphical representation readily permits appreciation and identification of aberrant patterns in severe constipation and may be an important clinical and research tool in the assessment of colonic motor disorders.

Rectal hyposensitivity: evaluation of anal sensation in female patients with refractory constipation with and without faecal incontinence

Rectal hyposensitivity (RH) is commonly found in patients with intractable constipation, faecal incontinence or both. Anal sensation may also be blunted in these conditions. We aimed to determine whether RH is associated with anal hyposensitivity, which may reflect a combined viscero-somatic neuropathy. One hundred and fifty-eight female patients with chronic constipation underwent physiological investigation including rectal sensation to volumetric balloon distension, and distal anal mucosal sensation to electrostimulation. Data were also obtained from 32 healthy female volunteers. Anal mucosal electrosensory thresholds were significantly higher in patients compared with volunteers (median: 2.4 mA, range: 0.4-19.6 vs 1.1 mA, range: 0.1-4.2, respectively), although the patient group was older (P < 0.0001), but there was no difference (P = 0.572) in the incidence of blunted anal sensation between those with normal rectal sensation (n = 113, 20% abnormal) and RH (n = 45, 24% abnormal). Irrespective of rectal sensory function, there was a strong association between symptom duration (P = 0.012) and anal hyposensitivity. One-fifth of constipated female patients had evidence of diminished anal sensation. However, the presence of RH was not associated with an increased frequency of anal hyposensitivity, thereby suggesting that different aetiopathogenic mechanisms underlie the development of anal and rectal hyposensitivity. Further studies in carefully selected, homogenous patient populations are necessary to elucidate these mechanisms.

Slow-transit constipation: evaluation and treatment

Slow-transit constipation is characterized by delay in transit of stool through the colon, caused by either myopathy or neuropathy. The severity of constipation is highly variable, but may be severe enough to result in complete cessation of spontaneous bowel motions. Diagnostic tests to assess colonic transit include radiopaque marker or radioisotope studies, and intraluminal tests (colonic and small bowel manometry). Most patients with functional constipation respond to laxatives, but a small proportion are resistant to this treatment. In some patients biofeedback is helpful although the mechanism by which this works is still uncertain. Other patients are resistant to all conservative modes of therapy and require surgical intervention. Extensive clinical and physiological preoperative assessment of patients with slow colonic transit is essential before considering surgery, including an assessment of small bowel motility and identification of coexistent obstructed defecation. The psychological state of the patient should always be taken into account. When surgery is indicated, subtotal colectomy and ileorectal anastomosis is the operation of choice. Segmental colonic resection has been reported in a few patients, but methods of identifying the affected segment need to be developed further. Less invasive and reversible surgical options include laparoscopic ileostomy, antegrade colonic enema and sacral nerve stimulation.

Colonic neuropathological aspects in patients with intractable constipation due to obstructed defecation

One of the most frequent subtypes of constipation is represented by obstructed defecation, and it has recently been reported that these patients may have colonic motor abnormalities in addition to alterations of the anorectal area. However, it is unknown whether these patients display abnormalities of the enteric nervous system, as reported in other groups of constipated subjects. For this reason, we evaluated the neuropathologic aspects of the enteric nervous system in a homogeneous group of patients with obstructed defecation. Colonic specimens from 11 patients (nine women, age range 39-66 years) undergoing surgery for symptoms refractory to any therapeutic measure, including biofeedback training, were obtained and examined by means of conventional histological methods and immunohistochemistry (NSE, S100, c-Kit, formamide-mAb, Bcl-2, CD34, alfa-actin). Analysis of the specimens showed that the enteric neurons were significantly decreased only in the submucosal plexus of patients (P<0.0001 vs controls), whereas the enteric glial cells of constipated patients were reduced in both the myenteric (P=0.018 vs controls) and the submucosal plexus (P=0.004 vs controls). No difference between patients and controls were found concerning c-Kit and CD34 expression, and the number of apoptotic neurons. These findings support the concept that at least a subgroup of patients with obstructed defecation and severe, intractable symptoms display abnormalities of the enteric nervous system, mostly related to the enteric glial cells. These findings might explain some of the pathophysiological abnormalities, and help to better understand this condition.