Ashok Attaluri

Digital rectal examination is a useful tool for identifying patients with dyssynergia.

BACKGROUND & AIMS Dyssynergic defecation is a common cause of chronic constipation; its diagnosis requires anorectal physiological tests that are not widely available. It is not known whether digital rectal examination (DRE) can be used to identify dyssynergia. We examined the diagnostic yield of DRE in patients with dyssynergic defecation. METHODS Consecutive patients with chronic constipation (Rome III criteria, n = 209) underwent DREs, anorectal manometry analyses, balloon expulsion tests, and colonic transit studies. In the DRE, dyssynergia was identified by 2 or more of the following features: impaired perineal descent, paradoxic anal contraction, or impaired push effort; diagnostic yields were compared with physiological test results. RESULTS Of the patients included in the study, 187 (87%) had dyssynergic defecation, based on standard criteria; 134 (73%) of these were identified to have features of dyssynergia, based on DREs. The sensitivity and specificity of DRE for identifying dyssynergia in patients with chronic constipation were 75% and 87%, respectively; the positive predictive value was 97%. DRE was able to identify normal resting and normal squeeze pressure in 86% and 82% of dyssynergic patients, respectively. CONCLUSIONS DRE appears to be a reliable tool for identifying dyssynergia in patients with chronic constipation and detecting normal, but not abnormal, sphincter tone. DREs could facilitate the selection of appropriate patients for further physiologic testing and treatment.

Methanogenic flora is associated with altered colonic transit but not stool characteristics in constipation without IBS

OBJECTIVES:About 35% of humans have methane-producing gut flora. Methane-producing irritable bowel syndrome (IBS) subjects are generally constipated. In animal models, methane infusion slows intestinal transit. Whether methanogenic flora alters colonic transit or stool characteristics and its relationship to constipation is unclear. The aim of this study was to examine the prevalence and association of methanogenic flora in patients with slow transit (ST) constipation and normal transit (NT) constipation and non-constipated controls.METHODS:Ninety-six consecutive subjects with chronic constipation (CC) (Rome III) were evaluated with radio-opaque marker (ROM) transit studies and were classified as ST (>20% ROM retention) or NT. All constipated subjects and 106 non-constipated controls underwent breath tests to assess methane production. Baseline CH4 of ≥3 p.p.m. was used to define presence of methanogenic flora. Stool frequency and consistency were assessed using a prospective stool diary. Correlation analyses were performed.RESULTS:Forty-eight subjects had ST and 48 had NT. Prevalence of methanogenic flora was higher (P<0.05) in ST (75%) compared to NT (44%) or controls (28%). ST patients had higher methane production compared to NT and controls (P<0.05). NT patients also produced more methane compared to controls (P<0.05). There was moderate(P<0.05) correlation among baseline, peak, and area under the curve (AUC) of methane response with colonic transit but not with stool characteristics.CONCLUSIONS:Presence of methanogenic flora is associated with CC. Methane production after carbohydrate challenge and its prevalence were higher in ST than NT, although stool characteristics were similar in both groups. Methane production correlated with colonic transit, suggesting an association with stool transport but not with stool characteristics.

Randomised clinical trial: dried plums (prunes) vs. psyllium for constipation.

Aliment Pharmacol Ther 2011; 33: 822–828

Dysmotility and proton pump inhibitor use are independent risk factors for small intestinal bacterial and/or fungal overgrowth

Whether intestinal dysmotility and the use of a proton pump inhibitor (PPI) either independently or together contributes to small intestinal bacterial overgrowth (SIBO), and/or small intestinal fungal overgrowth (SIFO) is not known.

Visceral hypersensitivity and impaired accommodation in refractory diabetic gastroparesis

Abstract  The pathophysiology of persistent gastrointestinal (GI) symptoms in patients with diabetic gastroparesis is poorly understood. Our aim was to evaluate gastric sensation and accommodation to a meal in patients with diabetic gastroparesis and refractory symptoms. We performed intermittent, phasic balloon distensions of the stomach using a gastric barostat device in 18 patients with diabetes and gastroparesis unresponsive to prokinetic therapy and in 13 healthy volunteers. We assessed the biomechanical, sensory and accommodation responses of the stomach, during fasting and after liquid meal. During balloon distension, the sensory thresholds for discomfort were lower (P < 0.02) in patients with diabetes than those in controls, in both the fasting and the postprandial states. The accommodation response to a meal was significantly impaired (P = 0.01) in patients with diabetes when compared to controls, although fasting gastric tone was similar (P = 0.08). Patients with diabetic gastroparesis and refractory GI symptoms demonstrate sensori‐motor dysfunction of the stomach, comprising either impaired accommodation, gastric hypersensitivity or both. An objective evaluation of these biomechanical and sensory properties may provide valuable mechanistic insights that could guide therapy.

Investigation of Esophageal Sensation and Biomechanical Properties in Functional Chest Pain

Background  There is limited and conflicting data regarding the role of esophageal hypersensitivity in the pathogenesis of functional chest pain (FCP). We examined esophageal sensori‐motor properties, mechanics, and symptoms in subjects with FCP.

Investigation of anal motor characteristics of the sensorimotor response (SMR) using 3-D anorectal pressure topography

Desire to defecate is associated with a unique anal contractile response, the sensorimotor response (SMR). However, the precise muscle(s) involved is not known. We aimed to examine the role of external and internal anal sphincter and the puborectalis muscle in the genesis of SMR. Anorectal 3-D pressure topography was performed in 10 healthy subjects during graded rectal balloon distention using a novel high-definition manometry system consisting of a probe with 256 pressure sensors arranged circumferentially. The anal pressure changes before, during, and after the onset of SMR were measured at every millimeter along the length of anal canal and in 3-D by dividing the anal canal into 4 × 2.1-mm grids. Pressures were assessed in the longitudinal and anterior-posterior axis. Anal ultrasound was performed to assess puborectalis morphology. 3-D topography demonstrated that rectal distention produced an SMR coinciding with desire to defecate and predominantly induced by contraction of puborectalis. Anal ultrasound showed that the puborectalis was located at mean distance of 3.5 cm from anal verge, which corresponded with peak pressure difference between the anterior and posterior vectors observed at 3.4 cm with 3-D topography (r = 0.77). The highest absolute and percentage increases in pressure during SMR were seen in the superior-posterior portion of anal canal, reaffirming the role of puborectalis. The SMR anal pressure profile showed a peak pressure at 1.6 cm from anal verge in the anterior and posterior vectors and distinct increase in pressure only posteriorly at 3.2 cm corresponding to puborectalis. We concluded that SMR is primarily induced by the activation and contraction of the puborectalis muscle in response to a sensation of a desire to defecate.

Diagnostic utility of wireless motility capsule in gastrointestinal dysmotility.

Goals To examine the diagnostic utility of wireless motility capsule (WMC) in patients with suspected gastrointestinal (GI) dysmotility. Background Subjects with suspected GI motility disorders undergo invasive and expensive diagnostic tests. In these patients, whether WMC provides clinically useful information is unknown. Study Patients with symptoms of dysmotility and normal endoscopic/radiologic evaluations were assessed with WMC test and conventional motility tests (CMT). Diagnostic utility of WMC was assessed retrospectively by examining device agreement and new information compared with CMT. Results On the basis of predominant symptom(s), 86 patients were classified into 2 subgroups: lower GI (LGI=50) and upper GI (UGI=36). Clinical suspicion was confirmed in 52% and 66% of patients, respectively, and there was good device agreement between WMC and CMT in 76% and 81% in the LGI and UGI groups, respectively. There was new diagnostic information with the WMC test in 53% of the LGI (P=0.006) and 47% of the UGI group (P=0.001). WMC detected generalized motility disorder in 44 (51%) patients and influenced management in 30% of LGI and 50% of UGI subjects. Conclusions WMC confirmed clinical suspicion, provided new diagnostic information, influenced clinical management, and detected many patients with generalized motility disorder. It had good device agreement with conventional tests.

Email teleconsultations: well formulated clinical referrals reduce the need for clinic consultation

We examined how well primary-care physicians formulated their clinical referrals when asking for help with patient-related clinical problems using an email-based teleconsultation service. Over 100 family physicians made use of the service. The specialists were medical school faculty members. The service was initiated in May 1996 with 19 specialists and expanded to 34 specialties over the next five years. A total of 1618 patient-related clinical questions were analysed, the outcome for the analysis being whether specialists recommended a clinic consultation. Specialists recommended a clinic consultation in response to 10% of their clinical questions about patients. There was a strong association between how family physicians formulated their clinical questions and whether the specialist recommended a clinic consultation. When the family physicians specified a clinical task (P<0.001), intervention (P=0.004) and outcome (P<0.001) in their questions, specialists were less likely to recommend a clinic consultation. This influence was independent of the amount of clinical information included with the question (P>0.05). About 5% of the questions that included all three question components resulted in the recommendation for a clinic consultation, compared with nearly 30% of the questions containing none of these components. How family physicians formulate their clinical questions influences whether specialists request a clinic consultation.

Translumbar and transsacral motor-evoked potentials: a novel test for spino-anorectal neuropathy in spinal cord injury.

OBJECTIVES:Spinal cord injury (SCI) causes anorectal problems, whose pathophysiology remains poorly characterized. A comprehensive method of evaluating spino-anorectal function is lacking. The aim of this study was to investigate the neuropathophysiology of bowel dysfunction in SCI by evaluating motor-evoked potentials (MEP) of anus and rectum following transspinal magnetic stimulation and anorectal physiology.METHODS:Translumbar and transsacral magnetic stimulations, anorectal manometry, and pudendal nerve terminal motor latency (PNTML) were performed in 39 subjects with SCI and anorectal problems and in 14 healthy controls, and data were compared. MEPs were recorded with an anorectal probe containing bipolar ring electrodes.RESULTS:The MEPs were significantly prolonged (P<0.05) bilaterally, and at lumbar and sacral levels, as well as at rectal and anal sites in SCI subjects compared with controls. A total of 95% of SCI subjects had abnormal MEPs and 53% had abnormal PNTML. All subjects with abnormal PNTML also demonstrated abnormal MEP, but 16/17 subjects with normal PNTML had abnormal MEP. Overall, SCI patients had weaker anal sphincters (P<0.05), higher prevalence of dyssynergia (85%), and altered rectal sensation (82%).CONCLUSIONS:Translumbar and transsacral MEPs revealed significant and hitherto undetected lumbosacral neuropathy in 90% of SCI subjects. Test was safe and provided neuropathophysiological information that could explain bowel dysfunction in SCI subjects.