Current tests of gastric and small intestinal motor function provide relevant physiological information, but their clinical utility is controversial. This article reviews the current procedures, ...indications, significance, pitfalls, and guidelines for gastrointestinal motility measurements by scintigraphy, gastroduodenojejunal manometry, and surface electrogastrography in humans. Methods included review of literature and discussions in closed and open fora among investigators, including presentations for peer review at focused (Iowa City American Motility Society Symposium, December 1995) and national meetings (American Gastroenterological Association, May 1996, and American Motility Society, September 1996). The current tests are generally complementary; scintigraphy is typically the first test in the evaluation of gastric motor function and often confirms the clinical suspicion of dysmotility. Manometry identifies patterns suggestive of myopathy, neuropathy, or obstruction but may be most helpful when it shows entirely normal findings, because manometry helps in part to exclude dysmotility as a cause of symptoms. Electrogastrography may identify dysrhythmias or failure of signal power to increase postprandially; rhythm abnormalities may be independent of impaired emptying among dyspeptic patients. The best validated and clinically most significant results pertain to transit tests; manometry may contribute importantly to the diagnostic process; and the significance of electrogastrography remains to be fully elucidated.
GASTROENTEROLOGY 1998;115:747-762
To ascertain the effect on body weight of 14 days of bolus enteral feeding with mixed meal (MM) and electrolyte solution (ES) in ambulatory adults with type 2 diabetes and obesity, and also the ...safety and feasibility of using a modified, intraorally anchored enteral feeding tube for this purpose.
We conducted a randomized, crossover pilot trial with 16 participants. A 140 cm, 8-French feeding tube was placed in the jejunum under electromagnetic guidance and anchored intraorally. Participants were randomized to self-administer 120 mL 523 kJ (125 kcal) MM, or 50 kJ (12 kcal) ES four times/day for 14 days. After ≥14 days without the tube, participants crossed over to the other treatment. The primary outcome compared weight change between treatments. Thereafter, participants could elect to undergo additional MM cycles. Participants were encouraged to continue with all usual activities including eating ad lib throughout the study.
Ten participants withdrew prior to completing two randomized 14-day cycles (4 social, 3 intolerant of anchor, and 3 intolerant of tube). Six participants were assessed for the primary outcome and showed no significant difference in weight loss between MM and ES (p = 0.082). For the secondary outcome of within-group weight loss, average weight loss from baseline was significant for MM but not for ES: -2.40 kg (95% CI: -3.78, -1.02; p = 0.008) vs. -0.64 kg (95% CI: -2.01, 0.74; p = 0.27). A total of 23 2-week cycles were completed (12 paired, 2 unpaired, and 9 additional), with no significant adverse events for 334 days of tube use.
Repeated bolus nutrient administration via enteral feeding tube is associated with weight loss in adults with obesity and type 2 diabetes, with no significant difference seen between MM and ES feeds. The prototype device was safe, but requires development for further investigation into the effect of bolus jejunal feeding on weight and to improve acceptability.
Background Electrical stimulation (ES) of the lower esophageal sphincter (LES) increases resting LES pressure (LESP) in animal models. Our aims were to evaluate the safety of such stimulation in ...humans, and test the hypothesis that ES increases resting LESP in patients with gastroesophageal reflux disease (GERD).
Methods A total of 10 subjects (nine female patients, mean age 52.6 years), with symptoms of GERD responsive to PPIs, low resting LES pressure, and abnormal 24‐h intraesophageal pH test were enrolled. Those with hiatal hernia >2 cm and/or esophagitis >Los Angeles Grade B were excluded. Bipolar stitch electrodes were placed longitudinally in the LES during an elective laparoscopic cholecystectomy, secured by a clip and exteriorized through the abdominal wall. Following recovery, an external pulse generator delivered two types of stimulation for periods of 30 min: (i) low energy stimulation; pulse width of 200 μs, frequency of 20 Hz and current of 5–15 mA (current was increased up to 15 mA if LESP was less than 15 mmHg), and (ii) high energy stimulation; pulse width of 375 ms, frequency of 6 cpm, and current 5 mA. Resting LESP, amplitude of esophageal contractions and residual LESP in response to swallows were assessed before and after stimulation. Symptoms of chest pain, abdominal pain, and dysphagia were recorded before, during, and after stimulation and 7‐days after stimulation. Continuous cardiac monitoring was performed during and after stimulation.
Key Results All patients were successfully implanted nine subjects received high frequency, low energy, and four subjects received low frequency, high energy stimulation. Both types of stimulation significantly increased resting LESP: from 8.6 mmHg (95% CI 4.1–13.1) to 16.6 mmHg (95% CI 10.8–19.2), P < 0.001 with low energy stimulation and from 9.2 mmHg (95% CI 2.0–16.3) to 16.5 mmHg (95% CI 2.7–30.1), P = 0.03 with high energy stimulation. Neither type of stimulation affected the amplitude of esophageal peristalsis or residual LESP. No subject complained of dysphagia. One subject had retrosternal discomfort with stimulation at15 mA that was not experienced with stimulation at 13 mA. There were no adverse events or any cardiac rhythm abnormalities with either type of stimulation.
Conclusions & Inferences Short‐term stimulation of the LES in patients with GERD significantly increases resting LESP without affecting esophageal peristalsis or LES relaxation. Electrical stimulation of the LES may offer a novel therapy for patients with GERD.
Background: Interstitial cells of Cajal (ICC) are required for normal intestinal motility. ICC are found throughout the human colon and are decreased in the sigmoid colon of patients with slow ...transit constipation. Aims: The aims of this study were to determine the normal distribution of ICC within the human colon and to determine if ICC are decreased throughout the colon in slow transit constipation. Patients: The caecum, ascending, transverse, and sigmoid colons from six patients with slow transit constipation and colonic tissue from patients with resected colon cancer were used for this study. Methods: ICC cells were identified with a polyclonal antibody to c-Kit, serial 0.5 μm sections were obtained by confocal microscopy, and three dimensional software was employed to reconstruct the entire thickness of the colonic muscularis propria and submucosa. Results: ICC were located within both the longitudinal and circular muscle layers. Two networks of ICC were identified, one in the myenteric plexus region and another, less defined network, in the submucosal border. Caecum, ascending colon, transverse colon, and sigmoid colon displayed similar ICC volumes. ICC volume was significantly lower in the slow transit constipation patients across all colonic regions. Conclusions: The data suggest that ICC distribution is relatively uniform throughout the human colon and that decreased ICC volume is pan-colonic in idiopathic slow transit constipation.
Purpose of Review
Populations with significant dietary fish intake tend to have lower cardiovascular (CV) risk and demonstrable physiologic differences including lower lipid/lipoprotein levels and ...other direct and indirect effects on the arterial wall and inhibiting factors that promote atherosclerosis. Treatment with high doses of pharmacologic-grade omega-3 fatty acid (
n
-3FA) supplements achieves significant reductions in triglycerides (TG), non-high-density lipoprotein- (non-HDL-) and TG-rich lipoprotein- (TRL-) cholesterol levels.
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-3FA supplements have significant effects on markers of atherosclerosis risk including endothelial function, low-density lipoprotein (LDL) oxidation, cellular and humoral markers of inflammation, hemodynamic factors, and plaque stabilization. This review summarizes the lipid and cardiometabolic effects of prescription-grade
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-3FAs and will discuss clinical trials, national/organizational guidelines, and expert opinion on the impact of supplemental
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-3FAs on CV health and disease.
Recent Findings
Clinical trial evidence supports use of
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3FAs in individuals with established atherosclerotic cardiovascular disease (ASCVD), but the data either does not support or is lacking for other types of cardiometabolic risk including prevention of stroke, treatment in patients with heart failure, diabetes mellitus and prediabetes, and for primary prevention in the general population.
Summary
Despite inconsistent findings to support widespread benefit, there is persistent population-wide enthusiasm for
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-3FA as a dietary supplement for its cardiometabolic benefits. Fortunately, there are ongoing clinical trials to assess whether the lipid/lipoprotein benefits may be extended to other at-risk populations and whether lower-dose therapy may provide background benefit for primary prevention of ASCVD.
The objective of this study was to determine the distribution of enteric nerves and interstitial cells of Cajal (ICC) in the normal human appendix and in type 1 diabetes. Appendixes were collected ...from patients with type 1 diabetes and from non‐diabetic controls. Volumes of nerves and ICC were determined using 3‐D reconstruction and neuronal nitric oxide synthase (nNOS) expressing neurons were counted. Enteric ganglia were found in the myenteric plexus region and within the longitudinal muscle. ICC were found throughout the muscle layers. In diabetes, c‐Kit positive ICC volumes were significantly reduced as were nNOS expressing neurons. In conclusion, we describe the distribution of ICC and enteric nerves in health and in diabetes. The data also suggest that the human appendix, a readily available source of human tissue, may be useful model for the study of motility disorders.
We have recently described an association between irritable bowel syndrome (IBS) and abnormal lactulose breath test, suggesting small intestinal bacterial overgrowth (SIBO). However, the mechanism by ...which SIBO develops in IBS is unknown. In this case-control study we evaluate the role of small intestinal motility in subjects with IBS and SIBO. Small intestinal motility was studied in consecutive IBS subjects with SIBO on lactulose breath test. After fluoroscopic placement of an eight-channel water-perfused manometry catheter, 4-hr fasting recordings were obtained. Based on this, the number and duration of phase III was compared to 30 control subjects. To test whether there was a relationship between the motility abnormalities seen and the SIBO status of the patient at the time of the motility, subjects with a breath test within 5 days of the antroduodenal manometry were also compared. Sixty-eight subjects with IBS and SIBO were compared to controls. The number of phase III events was 0.7 +/- 0.8 in IBS subjects and 2.2 +/- 1.0 in controls (P < 0.000001). The duration of phase III was 305 +/- 123 sec in IBS subjects and 428 +/- 173 in controls (P < 0.001). Subjects whose SIBO was still present at the time of manometry had less frequent phase III events than subjects with eradicated overgrowth (P < 0.05). In conclusion, phase III is reduced in subjects with IBS and SIBO. Eradication of bacterial overgrowth seems to result in some normalization of motility.
SUMMARY
Eosinophilic esophagitis (EoE) and reflux esophagitis (RE) overlap clinically and histologically. RE is characterized by epithelial infiltration with small numbers of neutrophils and ...eosinophils, EoE by a prominent eosinophilic infiltrate. Lymphocytic esophagitis (LE), a new entity characterized by peripapillary lymphocytosis, questions the role lymphocytes play in esophageal inflammation. We test the hypothesis that lymphocyte infiltration in RE differs from EoE. One blinded pathologist read esophageal biopsies from 39 RE and 39 EoE patients. Both groups demonstrated significant numbers of lymphocytes (RE 22.7 ± 2.2/HPF, EoE 19.8 ± 1.8/HPF). Eosinophils/HPF in RE and EoE were 2.8 ± 0.7 and 74.9 ± 8.2, respectively (P < 0.001). Neutrophils were uncommon in RE (0.26 ± 0.16/HPF) and EoE (0.09 ± 0.04; P = 0.07). Eight of the 39 RE specimens had ≥50 lymphocytes in ≥1 HPF. Two were consistent with LE. There was an inverse correlation between numbers of eosinophils and lymphocytes in EoE (R = −0.47; P = 0.002), and no correlation between them in RE (R = 0.18; P = 0.36). The patients with EoE who used antireflux medications had fewer lymphocytes (16.3 ± 1.3 vs 22.2 ± 2.3/HPF; P = 0.030) and eosinophils (55.6 ± 5.2 vs 76.0 ± 8.7/HPF; P = 0.042) than those who did not. The pathological role of lymphocytes in RE and EoE may be underestimated. Our observation that 5% of the RE specimens meet histopathological criteria for LE potentially blurs the line between these entities. The observation that eosinophil counts are lower in EoE when antireflux meds are used supports the notion that reflux plays a role in the clinical expression of EoE.
Manometry is used widely in the evaluation of esophageal disorders. Our aim was to assess the intra- and interobserver reliability of esophageal manometry and identify potential causes for diagnostic ...variability.
Seventy-two esophageal manometry tracings were selected randomly from archives. Eight interpreters randomly and blindly evaluated tracings. Interpreters were divided into 3 groups: highly experienced (N = 3), moderately experienced (N = 3), and inexperienced (N = 2). Each tracing was examined for abnormalities involving the lower-esophageal sphincter (LES) and esophageal body. Interpreters rendered a single diagnosis from a list of 7 manometric diagnoses: normal, nutcracker, hypertensive LES, hypotensive LES, diffuse esophageal spasm (DES), nonspecific/ineffective esophageal motility (IEM), and achalasia. Intra- and interobserver agreements were determined and reasons for varied diagnoses were investigated.
Overall intraobserver agreement was good (kappa = .63, P < .0001). There was no difference ( P = .9) between the highly and midexperienced interpreters (kappa = .61 and .65, respectively). Interobserver agreement for the diagnosis of achalasia and normal motility was good (kappa = .65 and .56, respectively). However, other manometric diagnoses yielded only fair interobserver agreement (kappa = .27). DES, nonspecific/ineffective esophageal motility (IEM), and hypo- and hypertensive LES diagnoses showed the least agreement. Poor adherence to established manometric criteria, misinterpretation of intrabolus pressure, and technical inadequacy were the most common sources of inconsistency in interpretations.
Manometric diagnoses of conditions other than normal or achalasia are variable and have poor interobserver variability. Given their uncertain clinical implications, we must either redefine them or eliminate them from practice.