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Concept: Defecation


The appendix may modulate colon microbiota and bowel inflammation. We investigated whether appendectomy alters colorectal cancer risk.

Concepts: Cancer, Colorectal cancer, Ulcerative colitis, Crohn's disease, Colon, Constipation, Large intestine, Defecation


Smooth muscle sphincters exhibit basal tone and control passage of contents through organs such as the gastrointestinal tract; loss of this tone leads to disorders such as faecal incontinence. However, the molecular mechanisms underlying this tone remain unknown. Here, we show that deletion of myosin light-chain kinases (MLCK) in the smooth muscle cells from internal anal sphincter (IAS-SMCs) abolishes basal tone, impairing defecation. Pharmacological regulation of ryanodine receptors (RyRs), L-type voltage-dependent Ca(2+) channels (VDCCs) or TMEM16A Ca(2+)-activated Cl(-) channels significantly changes global cytosolic Ca(2+) concentration ([Ca(2+)]i) and the tone. TMEM16A deletion in IAS-SMCs abolishes the effects of modulators for TMEM16A or VDCCs on a RyR-mediated rise in global [Ca(2+)]i and impairs the tone and defecation. Hence, MLCK activation in IAS-SMCs caused by a global rise in [Ca(2+)]i via a RyR-TMEM16A-VDCC signalling module sets the basal tone. Targeting this module may lead to new treatments for diseases like faecal incontinence.

Concepts: Cardiac muscle, Actin, Stomach, Muscle contraction, Skeletal muscle, Muscular system, Defecation, Sphincter


: The purpose of this study was to identify patient, clinical, and surgical factors that may predispose patients to anastomotic leak (AL) after large bowel surgery.

Concepts: Colon, Defecation


OBJECTIVE.: Fecal incontinence reduces the quality of life of many women but has no long-term cure. Research on mesenchymal stem cell (MSC)-based therapies has shown promising results. The primary aim of this study was to evaluate functional recovery after treatment with MSCs in two animal models of anal sphincter injury. METHODS.: Seventy virgin female rats received a sphincterotomy (SP) to model episiotomy, a pudendal nerve crush (PNC) to model the nerve injuries of childbirth, a sham SP, or a sham PNC. Anal sphincter pressures and electromyography (EMG) were recorded after injury but before treatment and 10days after injury. Twenty-four hours after injury, each animal received either 0.2ml saline or 2million MSCs labelled with green fluorescing protein (GFP) suspended in 0.2ml saline, either intravenously (IV) into the tail vein or intramuscularly (IM) into the anal sphincter. RESULTS.: MSCs delivered IV after SP resulted in a significant increase in resting anal sphincter pressure and peak pressure, as well as anal sphincter EMG amplitude and frequency 10days after injury. MSCs delivered IM after SP resulted in a significant increase in resting anal sphincter pressure and anal sphincter EMG frequency but not amplitude. There was no improvement in anal sphincter pressure or EMG with in animals receiving MSCs after PNC. GFP-labelled cells were not found near the external anal sphincter in MSC-treated animals after SP. CONCLUSION.: MSC treatment resulted in significant improvement in anal pressures after SP but not after PNC, suggesting that MSCs could be utilized to facilitate recovery after anal sphincter injury.

Concepts: Stem cell, Mesenchymal stem cell, Bone marrow, Stem cells, Adipocyte, Mesenchyme, Defecation, Sphincter


BACKGROUND: The aim of our study was to evaluate gas retention, abdominal symptoms and changes in girth circumference in females with bloating using an active or sham abdominal wall mechanical stimulation. METHODS: In 14 female patients, complaining of bloating (11 with irritable bowel syndrome and 3 with functional bloating according to the Rome III criteria) a gas mixture was continuously infused into the colon for 1 h (accommodation period). Abdominal perception and girth were measured. At the beginning of the 30-min period of free rectal gas evacuation (clearance period), an electromechanical device was positioned on the abdominal wall of all patients. The patients were randomly assigned to an active or a sham stimulation protocol group. Gas retention, perception and abdominal distension were measured at the end of the clearance period. RESULTS: All patients tolerated the volume (1,440 ml) of gas infused into the colon. Abdominal perception and girth measurements was similar in both groups during the accommodation period. At the end of the clearance, the perception score and the girth changes in the active and sham stimulation groups were similar (2.8 ± 2.0 vs. 1.4 ± 1.2, p = 0.2 and 4.9 ± 4.5 vs. 2.8 ± 2.3 mm, p = 0.3 active vs. sham, respectively). Furthermore, the mechanical stimulation of the abdominal wall did not significantly reduce gas retention (495 ± 101 ml vs. 566 ± 55, active vs. sham, p = 0.1). CONCLUSIONS: An external mechanical massage of the abdominal wall did not improve intestinal gas transit, abdominal perception and abdominal distension in our female patients complaining of functional bloating.

Concepts: Abdominal pain, Constipation, Intestine, Gastroenterology, Irritable bowel syndrome, Flatulence, Defecation, Abdominal distension


BACKGROUND/AIMS: Chronic constipation is frequently seen in women who have undergone hysterectomy or delivery. However, reports regarding anorectal physiologic features in those patients are rare. We analyzed the constipated patients associated with either radical hysterectomy or vaginal delivery in order to clarify the anorectal physiologic features and the effectiveness of biofeedback therapy. METHODS: Of the constipated patients, we included a hysterectomy group (n=40), delivery group (n=41), and a control group (n=89), who had no history of either surgery or delivery before developing functional constipation. We investigated their anorectal physiological tests and the effectiveness of biofeedback therapy. RESULTS: The volume of desire to defecate was greater in the hysterectomy group than in the control group (86.5±55.0 mL vs. 62.9±33.7 mL; P=0.03), and more than 240 ml of maximal volume of toleration was more frequently noted in the hysterectomy group (32.5%) than in the delivery group (14.6%) and control group (13.5%) (P=0.02).The failure of balloon expulsion was more frequently noted in delivery group (44.0%) than in the hysterectomy group (15.0%) and control group (25.0%) (P=0.01). The defecation satisfaction score was significantly increased after biofeedback therapy in the hysterectomy group (2.0 ± 2.7 vs. 7.8 ± 1.5, P<0.001), the delivery group (1.6 ± 2.1 vs. 6.7 ± 2.0, P<0.001) and the control group (2.5 ± 2.7 vs. 6.9 ± 2.1, P<0.001). CONCLUSIONS: Rectal hyposensitivity could have been the characteristic mechanism in the hysterectomy group, whereas dyssynergic defecation could have been the cause in the delivery group. Biofeedback therapy was effective for both groups.

Concepts: Childbirth, Physiology, Colon, Constipation, Dietary fiber, Rectum, Defecation, Anismus


AIM: This retrospective study aimed to determine functional results of Laparoscopic Ventral Rectopexy (LVR) for rectal prolapse (RP) and symptomatic rectoceles in a large cohort of patients. METHODS: All patients treated between 2004 and 2011 were identified. Relevant patient characteristics were gathered. A questionnaire concerning disease related symptoms as well as the Cleveland Clinic Incontinence Score (CCIS) and Cleveland Clinic Constipation Score (CCCS) was sent to all patients. RESULTS: A total 245 patients were operated. Twelve patients (5%) deceased during follow-up (FU) and were excluded. Remaining patients (224 females, 9 males) were sent a questionnaire. Indications for LVR were: external RP (n=36), internal RP or symptomatic rectocele (n=157) or a combination of symptomatic rectocele and enterocele (n=40). Mean age and follow-up were 62 years (range: 22-89) and 30 months (range 5-83), respectively. Response rate was 64% (150 patients). The complication rate was 4.6% (11 complications). A significant reduction in symptoms of constipation or obstructed defecation syndrome (ODS) was reported (53% of patients before vs. 19% after surgery, P< 0.001). Mean CCCS during FU was 8.1 points (range 0-23, SD ± 4.3). Incontinence was reported in 138 patients (59%) before surgery and in 32 patients after surgery (14%), indicating a significant reduction (P<0.001). Mean CCIS was 6.7 (range 0-19, SD ± 5.2) after surgery. CONCLUSION: A significant reduction of incontinence and constipation or ODS after LVR was observed in this large retrospective study. LVR therefore appears a suitable treatment for RP and rectocele with and without associated enterocele. © 2013 The Authors. Colorectal Disease © 2013 The Association of Coloproctology of Great Britain and Ireland.

Concepts: Surgery, Colorectal cancer, Colon, Constipation, Rectum, United Kingdom of Great Britain and Ireland, Defecation, Cleveland


AIM: Laparoscopic Ventral mesh rectopexy (LVMR) is increasingly recognised as having utility in rectal prolapse, obstructed defaecation (ODS), faecal incontinence (FI) and multi-compartment pelvic floor dysfunction (PFD). This study aimed to highlight gaps in service provision and areas for improvement by examining a cohort of patients with complications referred to a tertiary center. METHOD: Examination was carried out of a password protected electronic database of all LVMRs operated on in one institution. RESULTS: 50 patients (45 female) aged 24-71 (median 54) years were referred with early symptomatic failure (n=27) following an inadequate LVMR or major mesh complications (erosion into other organ, fistulation, stricturing) (n=23). All were amenable to remedial laparoscopic surgery. Functional improvements in pre- and postoperative ODS, Wexner (FI) scores (two tailed t test; p<0.0001) and QoL (BBUSQ-22) scores at 3 months (two tailed t test; p<0.001) and normalization at one year (p<0.015). This was mirrored by improved Linear Bowel Severity VAS scores (two tailed t test; p < 0.0001 [3/12] and p = 0.0151 [at 1 year]. CONCLUSION: LVMR can be associated with technical complications arising from inadequate technique, or operation specific complications that are amenable to complex revisional laparoscopic surgery with significant improvement in quality of life and function. © 2013 The Authors. Colorectal Disease © 2013 The Association of Coloproctology of Great Britain and Ireland.

Concepts: Better, Improve, Surgery, Tertiary referral hospital, Laparoscopic surgery, Rectum, United Kingdom of Great Britain and Ireland, Defecation


♦ Background: Fructo-oligosaccharides (FOS) exhibit soluble-fiber properties that beneficially affect bowel function and relieve constipation. The effects of FOS supplementation on constipation and biochemical parameters were examined in elderly continuous ambulatory peritoneal dialysis (CAPD) patients. ♦ Methods: This randomized, double-blind, placebo-controlled, cross-over study was performed in elderly CAPD patients (5 males and 4 females) with chronic constipation. All subjects were randomly assigned to receive either 20 g FOS or placebo daily for 30 days. After a 14-day washout period, the patients were switched to the other substance for 1 more month. Before and after each treatment period, frequency of defecation, characteristics of feces, and colonic transit were evaluated. Biochemical parameters were also assessed. ♦ Results: Fructo-oligosaccharides significantly increased the frequency of defecation (10.5 ± 2.0 vs 6.2 ± 1.4 times per week, p < 0.005) and changed the feces' appearance from type 1 (nut-like) to type 4 (sausage-like). The colonic transit determined by geometric center (GC) was augmented after FOS supplementation (3.9 ± 0.3 vs 3.2 ± 0.4, p < 0.05). Fructo-oligosaccharides had no effects on biochemical parameters. Fructo-oligosaccharides caused mild discomforts which were well tolerated after dose adjustment. ♦ Conclusions: Fructo-oligosaccharide supplementation is effective, well tolerated, and can be an alternative to other laxatives in CAPD patients with constipation. Further studies are needed to better assess the biochemical effects of FOS in the chronic kidney disease population.

Concepts: Chronic kidney disease, Nephrology, Dialysis, Hemodialysis, Constipation, Peritoneum, Peritoneal dialysis, Defecation


The position that we adopt to evacuate “waste matters” may potentially have an impact on the efficiency with which these are expelled. Proponents of squatting have eloquently described associated “health benefits” and have hinted that nonsquatters may be prone to urological, gynecological, and colorectal disorders. In this original piece of research, the effects of posture on micturition have been studied in various positions with interesting results.

Concepts: Urination, Woman, Defecation, Toilet, Toilet training, Toilet-related injury