Prevalence of Disaccharidase Deficiency in Adults With Unexplained Gastrointestinal Symptoms

Background/Aims@#Disaccharidase assay is used for assessing carbohydrate intolerance in children, but its usefulness in adults is not known. The aim of this study is to assess the prevalence of disaccharidase deficiency in patients with unexplained gastrointestinal symptoms. @*Methods@#A retrospective review of adults with chronic (> 1 year) abdominal symptoms and negative imaging and endoscopy/colonoscopy and who completed bowel symptom questionnaire and duodenal biopsy for lactase, maltase, sucrase, and palatinase was performed. A subset also underwent 25 g lactose breath test (LBT). @*Results@#One hundred twenty patients (females = 83) were evaluated, of whom 48 also underwent LBT. Fifty-six (46.7%) patients had enzyme deficiency; 44 (36.7%) had single (either lactase or maltase), 1 had 3 enzyme deficiencies, 11 (9.2 %) had all 4 disaccharidase enzyme (pan-disaccharidase) deficiency, and 64 (53.0%) had normal enzyme levels. Baseline prevalence and severity of 11 gastrointestinal symptoms were similar between normal and single enzyme deficiency groups. The sensitivity and specificity of LBT was 78.3% and 72.0%, respectively and overall agreement with lactase deficiency was 75.0%. @*Conclusions@#Isolated disaccharidase deficiency occurs in adults, usually lactase and rarely maltase, and pan-disaccharidase deficiency is rare. Baseline symptoms or its severity did not predict enzyme deficiency.

Update on the Pathophysiology and Management of Anorectal Disorders

Anorectal disorders are common and present with overlapping symptoms. They include several disorders with both structural and functional dysfunction(s). Because symptoms alone are poor predictors of the underlying pathophysiology, a diagnosis should only be made after evaluating symptoms and physiologic and structural abnormalities. A detailed history, a thorough physical and digital rectal examination and a systematic evaluation with high resolution and/or high definition three-dimensional (3D) anorectal manometry, 3D anal ultrasonography, magnetic resonance defecography and neurophysiology tests are essential to correctly identify these conditions. These physiological and imaging tests play a key role in facilitating a precise diagnosis and in providing a better understanding of the pathophysiology and functional anatomy. In turn, this leads to better and more comprehensive management using medical, behavioral and surgical approaches. For example, patients presenting with difficult defecation may demonstrate dyssynergic defecation and will benefit from biofeedback therapy before considering surgical treatment of coexisting anomalies such as rectoceles or intussusception. Similarly, patients with significant rectal prolapse and pelvic floor dysfunction or patients with complex enteroceles and pelvic organ prolapse may benefit from combined behavioral and surgical approaches, including an open, laparoscopic, transabdominal or transanal, and/or robotic-assisted surgery. Here, we provide an update on the pathophysiology, diagnosis, and management of selected common anorectal disorders.

Anorectal Manometry in Defecatory Disorders: A Comparative Analysis of High-resolution Pressure Topography and Waveform Manometry

BACKGROUND/AIMS: Whether high-resolution anorectal pressure topography (HRPT), having better fidelity and spatio-temporal resolution is comparable to waveform manometry (WM) in the diagnosis and characterization of defecatory disorders (DD) is not known. METHODS: Patients with chronic constipation (Rome III) were evaluated for DD with HRPT and WM during bearing-down “on-bed” without inflated rectal balloon and “on-commode (toilet)” with 60-mL inflated rectal balloon. Eleven healthy volunteers were also evaluated. RESULTS: Ninety-three of 117 screened participants (F/M = 77/16) were included. Balloon expulsion time was abnormal (> 60 seconds) in 56% (mean 214.4 seconds). A modest correlation between HRPT and WM was observed for sphincter length (R = 0.4) and likewise agreement between dyssynergic subtypes (κ = 0.4). During bearing down, 2 or more anal pressure-segments (distal and proximal) could be appreciated and their expansion measured with HRPT but not WM. In constipated vs healthy participants, the proximal segment was more expanded (2.0 cm vs 1.0 cm, P = 0.003) and of greater pressure (94.8 mmHg vs 54.0 mmHg, P = 0.010) during bearing down on-commode but not on-bed. CONCLUSIONS: Because of its better resolution, HRPT may identify more structural and functional abnormalities including puborectal dysfunction (proximal expansion) than WM. Bearing down on-commode with an inflated rectal balloon may provide additional dimension in characterizing DD.

Diagnosis and Treatment of Dyssynergic Defecation

Dyssynergic defecation is common and affects up to one half of patients with chronic constipation. This acquired behavioral problem is due to the inability to coordinate the abdominal and pelvic floor muscles to evacuate stools. A detailed history, prospective stool diaries, and a careful digital rectal examination will not only identify the nature of bowel dysfunction, but also raise the index of suspicion for this evacuation disorder. Anorectal physiology tests and balloon expulsion test are essential for a diagnosis. Newer techniques such as high-resolution manometry and magnetic resonance defecography can provide mechanistic insights. Recently, randomized controlled trials have shown that biofeedback therapy is more effective than laxatives and other modalities, both in the short term and long term, without side effects. Also, symptom improvements correlated with changes in underlying pathophysiology. Biofeedback therapy has been recommended as the first-line of treatment for dyssynergic defecation. Here, we provide an overview of the burden of illness and pathophysiology of dyssynergic defecation, and how to diagnose and treat this condition with biofeedback therapy.

How to Perform and Assess Colonic Manometry and Barostat Study in Chronic Constipation

Management of chronic constipation with refractory symptoms can be challenging. Although new drugs and behavioral treatments have improved outcome, when they fail, there is little guidance on what to do next. At this juncture, typically most doctors may refer for surgical intervention although total colectomy is associated with morbidity including complications such as recurrent bacterial overgrowth. Recently, colonic manometry with sensory/tone/compliance assessment with a barostat study has been shown to be useful. Technical challenges aside, adequate preparation, and appropriate equipment and knowledge of colonic physiology are keys for a successful procedure. The test itself appears to be safe with little complications. Currently, colonic manometry is usually performed with a 6-8 solid state or water-perfused sensor probe, although high-resolution fiber-optic colonic manometry with better spatiotemporal resolutions may become available in the near future. For a test that has evolved over 3 decades, normal physiology and abnormal findings for common phenotypes of chronic constipation, especially slow transit constipation, have been well characterized only recently largely through the advent of prolonged 24-hour ambulatory colonic manometry studies. Even though the test has been largely restricted to specialized laboratories at the moment, emerging new technologies and indications may facilitate its wider use in the near future.

Optimal Testing for Diagnosis of Fructose Intolerance: Over-dosage Leads to False Positive Intolerance Test

No abstract available.

How to Assess Regional and Whole Gut Transit Time With Wireless Motility Capsule

Assessment of transit through the gastrointestinal tract provides useful information regarding gut physiology and pathophysiology. Although several methods are available, each has distinct advantages and limitations. Recently, an ingestible wireless motility capsule (WMC), similar to capsule video endoscopy, has become available that offers a less-invasive, standardized, radiation-free and office-based test. The capsule has 3 sensors for measurement of pH, pressure and temperature, and collectively the information provided by these sensors is used to measure gastric emptying time, small bowel transit time, colonic transit time and whole gut transit time. Current approved indications for the test include the evaluation of gastric emptying in gastroparesis, colonic transit in constipation and evaluation of generalised dysmotility. Rare capsule retention and malfunction are known limitations and some patients may experience difficulty with swallowing the capsule. The use of WMC has been validated for the assessment of gastrointestinal transit. The normal range for transit time includes the following: gastric emptying (2-5 hours), small bowel transit (2-6 hours), colonic transit (10-59 hours) and whole gut transit (10-73 hours). Besides avoiding the use of multiple endoscopic, radiologic and functional gastrointestinal tests, WMC can provide new diagnoses, leads to a change in management decision and help to direct further focused work-ups in patients with suspected disordered motility. In conclusion, WMC represents a significant advance in the assessment of segmental and whole gut transit and motility, and could prove to be an indispensable diagnostic tool for gastrointestinal physicians worldwide.