Does a glucose-based hydrogen and methane breath test detect bacterial overgrowth in the jejunum?

BACKGROUND

Direct diagnosis of small intestinal bacterial overgrowth (SIBO) requires the collection and culture of fluid from the jejunal lumen, with a finding of over 10⁵ viable bacteria per mL. More often, SIBO is diagnosed indirectly, using a non-invasive test of the exhaled hydrogen and methane generated by microbial fermentation when ingested glucose reaches the jejunum. Our objective was to determine how well this breath test detects chronic overgrowth of jejunal bacteria that is unrelated to gastrointestinal surgery.

METHODS

Eighteen patients reporting symptoms consistent with SIBO received a glucose breath test. On a later day, the jejunal lumen was sampled via aspiration during enteroscopy. Jejunal aspirates were cultured on aerobic and anaerobic media. DNA was extracted from the same samples and analyzed by quantitative pan-bacterial PCR amplification of 16S ribosomal rRNA genes, which provided a culture-independent bacterial cell count.

KEY RESULTS

Combined bacterial colony counts ranged from 5.7 x 10³ to 7.9 x 10⁶ CFU/mL. DNA-based yields ranged from 1.5 x 10⁵ to 3.1 x 10⁷ bacterial genomes per mL. Microbial viability ranged from 0.3% to near 100%. We found no significant correlation of glucose breath test results with either the number of bacterial colonies or with the DNA-based bacterial cell counts. Instead, higher signals in the hydrogen-methane breath test were significantly correlated with a lower viability of jejunal bacteria, at a P-value of .014.

CONCLUSIONS & INFERENCES

The glucose-based hydrogen and methane breath test is not sensitive to the overgrowth of jejunal bacteria. However, a positive breath test may indicate altered jejunal function and microbial dysbiosis.

Efficacy of needleless transcutaneous electroacupuncture in synchronization with breathing for symptomatic idiopathic gastroparesis: A blinded and controlled acute treatment trial

BACKGROUND

Needleless transcutaneous electroacupuncture (TEA) improves nausea and myoelectrical activity in diabetic gastroparesis (GP). Synchronized TEA (STEA), which combines synchronized breathing with TEA, is more potent than TEA in enhancing vagal activity in healthy subjects.

AIMS

To investigate whether STEA improves symptoms, electrogastrogram (EGG) and vagal activity in idiopathic gastroparesis (IGP).

METHODS

Eighteen IGP subjects underwent 2 randomized visits (sham at non-acupoints or real STEA at acupoints) consisted of a 30-minute baseline, an Ensure challenge to provoke nausea, followed by 60-minute treatment with sham or real STEA, and 15-minute observation period. Severity of nausea, EGG, and vagal activity (based on electrocardiogram and serum Pancreatic Polypeptide, PP) were recorded.

RESULTS

In sham or STEA, the nausea scores of 2.7 ± 0.5 and 1.9 ± 0.5 at fasting baseline, respectively, increased to 5.9 ± 0.4 and 5.8 ± 0.3 during Ensure test (P < .05, vs baseline), subsequently reduced to 3.4 ± 0.6 with sham or 3.6 ± 0.6 with STEA, respectively (P < .05, vs Ensure period). Experiments with sham and STEA started with similar % of normal waves on EGG (66.4 ± 3.9 and 61.8 ± 3.0, respectively); decreased to 63. 5 ± 4.1 and 58.2 ± 2.8 during the Ensure test. After STEA, there was ~24% increase in % of normal waves, significantly different from the sham (6.0%) (P < .01). In sham or STEA, vagal activity was identical at baseline and after the Ensure. STEA induced a 3-fold increase in vagal activity compared with sham (P < .01). Ensure increased serum PP levels, and both treatments decreased the PP CONCLUSIONS: In IGP, STEA is not superior to Sham in decreasing nausea, but is more effective in improving gastric dysrhythmia.

Reactive oxygen species overproduction and MAP kinase phosphatase-1 degradation are associated with gastroparesis in a streptozotocin-induced male diabetic rat model

BACKGROUND

Diabetic gastroparesis in human and animal models suggest different developmental causes in females vs males. Previously, we demonstrated that although male and female diabetic gastroparetic rats exhibited similarity in disease pathology, molecular mechanisms were different: slow gastric emptying in male diabetic gastroparetic rats was not associated with the level of expression and dimerization of neuronal nitric oxide synthase α in gastric tissues, as was demonstrated in females. Male gastroparesis may involve other mechanisms, such as oxidative stress. We hypothesize that sustained increased reactive oxygen species (ROS) and degradation of MAP kinase phosphatase-1 with subsequent unregulated activation of c-Jun N-terminal kinase and p38MAP kinase pathways are associated with gastroparesis in a male diabetic rat model.

METHODS

Using a male rat model of diabetic gastroparesis, we analyzed serum and pyloric tissue for ROS and antioxidant enzyme levels using ELISA; MAP kinase phosphatase-1, c-Jun N-terminal kinases, and p38MAP kinase levels utilized western blotting techniques and phospho-specific antibodies.

KEY RESULTS

Both diabetic and diabetic gastroparetic rats demonstrated overproduction of ROS. However, loss of MAP kinase phosphatase-1, a MAP kinase pathway negative regulator, with subsequent activation of c-Jun N-terminal kinase 2 and p38MAP kinase pathways, were observed only in diabetic gastroparetic rats. Diabetic rats without gastroparesis had no significant pathway activation.

CONCLUSIONS & INFERENCES

These results suggest that sustained, increased ROS and degradation of MAP kinase phosphatase-1, with subsequent unregulated activation of c-Jun N-terminal kinase and p38MAP kinase pathways, are likely to be factors in diabetic gastroparesis phenotype in a male diabetic rat model.

Relating gastric scintigraphy and symptoms to motility capsule transit and pressure findings in suspected gastroparesis

BACKGROUND

Wireless motility capsule (WMC) findings are incompletely defined in suspected gastroparesis. We aimed to characterize regional WMC transit and contractility in relation to scintigraphy, etiology, and symptoms in patients undergoing gastric emptying testing.

METHODS

A total of 209 patients with gastroparesis symptoms at NIDDK Gastroparesis Consortium centers underwent gastric scintigraphy and WMCs on separate days to measure regional transit and contractility. Validated questionnaires quantified symptoms.

KEY RESULTS

Solid scintigraphy and liquid scintigraphy were delayed in 68.8% and 34.8% of patients; WMC gastric emptying times (GET) were delayed in 40.3% and showed 52.8% agreement with scintigraphy; 15.5% and 33.5% had delayed small bowel (SBTT) and colon transit (CTT) times. Transit was delayed in ≥2 regions in 23.3%. Rapid transit was rarely observed. Diabetics had slower GET but more rapid SBTT versus idiopathics (P ≤ .02). GET delays related to greater scintigraphic retention, slower SBTT, and fewer gastric contractions (P ≤ .04). Overall gastroparesis symptoms and nausea/vomiting, early satiety/fullness, bloating/distention, and upper abdominal pain subscores showed no relation to WMC transit. Upper and lower abdominal pain scores (P ≤ .03) were greater with increased colon contractions. Constipation correlated with slower CTT and higher colon contractions (P = .03). Diarrhea scores were higher with delayed SBTT and CTT (P ≤ .04).

CONCLUSIONS & INFERENCES

Wireless motility capsules define gastric emptying delays similar but not identical to scintigraphy that are more severe in diabetics and relate to reduced gastric contractility. Extragastric transit delays occur in >40% with suspected gastroparesis. Gastroparesis symptoms show little association with WMC profiles, although lower symptoms relate to small bowel or colon abnormalities.

Colonic immune cells in irritable bowel syndrome: A systematic review and meta-analysis

BACKGROUND & AIMS

Increases in mucosal immune cells have frequently been observed in irritable bowel syndrome (IBS) patients. However, this finding is not completely consistent between studies, possibly due to a combination of methodological variability, population differences and small sample sizes. We performed a meta-analysis of case-control studies that compared immune cell counts in colonic biopsies of IBS patients and controls.

METHODS

PubMed and Embase were searched in February 2017. Results were pooled using standardized mean difference (SMD) and were considered significant when zero was not within the 95% confidence interval (CI). Heterogeneity was assessed based on I² statistics where I²  ≤ 50% and I²  > 50% indicated fixed and random effect models, respectively.

KEY RESULTS

Twenty-two studies on 706 IBS patients and 401 controls were included. Mast cells were increased in the rectosigmoid (SMD: 0.38 [95% CI: 0.06-0.71]; P = .02) and descending colon (SMD: 1.69 [95% CI: 0.65-2.73]; P = .001) of IBS patients. Increased mast cells were observed in both constipation (IBS-C) and diarrhea predominant IBS (IBS-D). CD3⁺ T cells were increased in the rectosigmoid (SMD: 0.53 [95% CI: 0.21-0.85]; P = .001) and the descending colon of the IBS patients (SMD: 0.79, 95% CI [0.28-1.30]; P = .002). This was possibly in relation to higher CD4⁺ T cells in IBS (SMD: 0.33 [95% CI: 0.01-0.65]; P = .04) as there were no differences in CD8⁺ T cells.

CONCLUSIONS & INFERENCES

Mast cells and CD3⁺ T cells are increased in colonic biopsies of patients with IBS vs non-inflamed controls. These changes are segmental and sometimes IBS-subtype dependent. The diagnostic value of the quantification of colonic mucosal cells in IBS requires further investigation.

Diabetic and idiopathic gastroparesis is associated with loss of CD206-positive macrophages in the gastric antrum

BACKGROUND

Animal studies have increasingly highlighted the role of macrophages in the development of delayed gastric emptying. However, their role in the pathophysiology of human gastroparesis is unclear. Our aim was to determine changes in macrophages and other cell types in the gastric antrum muscularis propria of patients with diabetic and idiopathic gastroparesis.

METHODS

Full thickness gastric antrum biopsies were obtained from patients enrolled in the Gastroparesis Clinical Research Consortium (11 diabetic, 6 idiopathic) and 5 controls. Immunolabeling and quantitative assessment was done for interstitial cells of Cajal (ICC) (Kit), enteric nerves protein gene product 9.5, neuronal nitric oxide synthase, vasoactive intestinal peptide, substance P, tyrosine hydroxylase), overall immune cells (CD45) and anti-inflammatory macrophages (CD206). Gastric emptying was assessed using nuclear medicine scintigraphy and symptom severity using the Gastroparesis Cardinal Symptom Index.

RESULTS

Both diabetic and idiopathic gastroparesis patients showed loss of ICC as compared to controls (Mean [standard error of mean]/hpf: diabetic, 2.28 [0.16]; idiopathic, 2.53 [0.47]; controls, 6.05 [0.62]; P=.004). Overall immune cell population (CD45) was unchanged but there was a loss of anti-inflammatory macrophages (CD206) in circular muscle (diabetic, 3.87 [0.32]; idiopathic, 4.16 [0.52]; controls, 6.59 [1.09]; P=.04) and myenteric plexus (diabetic, 3.83 [0.27]; idiopathic, 3.59 [0.68]; controls, 7.46 [0.51]; P=.004). There was correlation between the number of ICC and CD206-positive cells (r=.55, P=.008). Enteric nerves (PGP9.5) were unchanged: diabetic, 33.64 (3.45); idiopathic, 41.26 (6.40); controls, 46.80 (6.04).

CONCLUSION

Loss of antral CD206-positive anti-inflammatory macrophages is a key feature in human gastroparesis and it is associates with ICC loss.

Depleted interstitial cells of Cajal and fibrosis in the pylorus: Novel features of gastroparesis

BACKGROUND

Depletion and ultrastructural changes of interstitial cells of Cajal (ICC) in the gastric body and antrum have been observed in gastroparesis. This research was performed to investigate the ICC population in the muscularis propria and fibrosis of the muscular layer of the pylorus in gastroparesis.

METHODS

Full thickness pyloric and antral biopsies were obtained from 17 gastroparetic and 6 non-gastroparetic controls. Biopsies were stained with C-Kit for ICC and Trichrome for collagen fibrosis. Interstitial cells of Cajal depletion in the antrum was defined as mean ICC count <10 per 20 high power fields (HPF) based on established data.

KEY RESULTS

The average pyloric ICC count was ≥10/HPF in the control patients. Twelve (70.5%) gastroparetic patients had pyloric ICC loss. Only five patients (29.4%) had ICC loss in the antrum. Gastric emptying (GE) was not significantly different in patients with depleted vs normal pyloric ICC. However, GE at 2 h was slower in patients with antral ICC <10/HPF compared to those with normal antral ICC populations. Collagen fibrosis was observed in the pylorus of 14 (82.3%) patients. Inclusion bodies in the muscularis propria of the pylorus were identified in four patients, all with diabetic gastroparesis.

CONCLUSIONS & INFERENCES

In gastroparetic patients, ICC loss in the pylorus is twice as common as in the antrum and fibrosis in the pyloric smooth muscle is nearly three times more common than the antrum. These findings can provide one explanation for pyloric dysfunction which is a contributing factor to the pathophysiology of gastroparesis.

Thermodynamic database for the Co-Pr system

In this article, we describe data on (1) compositions for both as-cast and heat treated specimens were summarized in Table 1; (2) the determined enthalpy of mixing of liquid phase is listed in Table 2; (3) thermodynamic database of the Co-Pr system in TDB format for the research articled entitle Chemical partitioning for the Co-Pr system: First-principles, experiments and energetic calculations to investigate the hard magnetic phase W.

Neutron-scattering measurements of spin excitations in LaFeAsO and Ba(Fe(0.953)Co(0.047))(2)As(2): evidence for a sharp enhancement of spin fluctuations by nematic order

Inelastic neutron scattering is employed to investigate the impact of electronic nematic order on the magnetic spectra of LaFeAsO and Ba(Fe(0.953)Co(0.047))(2)As(2). These materials are ideal to study the paramagnetic-nematic state, since the nematic order, signaled by the tetragonal-to-orthorhombic transition at T(S), sets in well above the stripe antiferromagnetic ordering at T(N). We find that the temperature-dependent dynamic susceptibility displays an anomaly at T(S) followed by a sharp enhancement in the spin-spin correlation length, revealing a strong feedback effect of nematic order on the low-energy magnetic spectrum. Our findings can be consistently described by a model that attributes the structural or nematic transition to magnetic fluctuations, and unveils the key role played by nematic order in promoting the long-range stripe antiferromagnetic order in iron pnictides.

Giant magnetic anisotropy and tunnelling of the magnetization in Li₂(Li(1-x)Fe(x))N

Large magnetic anisotropy and coercivity are key properties of functional magnetic materials and are generally associated with rare earth elements. Here we show an extreme, uniaxial magnetic anisotropy and the emergence of magnetic hysteresis in Li₂(Li(1-x)Fe(x))N. An extrapolated, magnetic anisotropy field of 220 T and a coercivity field of over 11 T at 2 K outperform all known hard ferromagnets and single-molecular magnets. Steps in the hysteresis loops and relaxation phenomena in striking similarity to single-molecular magnets are particularly pronounced for x≪1 and indicate the presence of nanoscale magnetic centres. Quantum tunnelling, in the form of temperature-independent relaxation and coercivity, deviation from Arrhenius behaviour and blocking of the relaxation, dominates the magnetic properties up to 10 K. The simple crystal structure, the availability of large single crystals and the ability to vary the Fe concentration make Li₂(Li(1-x)Fe(x))N an ideal model system to study macroscopic quantum effects at elevated temperatures and also a basis for novel functional magnetic materials.

Phase 2b, randomized, double-blind 12-week studies of TZP-102, a ghrelin receptor agonist for diabetic gastroparesis

BACKGROUND

TZP-102, a potent, oral, ghrelin receptor agonist, improved diabetic gastroparesis symptoms in Phase 2a.

METHODS

Patients with type 1 or 2 diabetes, delayed gastric half-emptying (T(1/2)), and ≥3 months gastroparesis symptoms randomized 1 : 1 : 1 to double-blind placebo, 10-mg, or 20-mg TZP-102 once daily for 12 weeks (Study TZP-102-CL-G003). Study TZP-102-CL-G004 patients randomized 1 : 1 to 10-mg TZP-102:placebo three-times-daily. Primary endpoint was change-from-baseline through Weeks 11-12 in Daily Diary of Gastroparesis Symptoms Questionnaire (GSDD) via electronic Patient Recorded Outcome device: worst severity of nausea, early satiety, bloating, and upper abdominal pain in 24 h (0 = none-to-5 = very severe). GSDD Composite Score for eligibility was ≥2.5 (Day-14-to-baseline). Patient Overall Treatment Evaluation (OTE) provided an anchor-based minimal clinically important difference (MCID) for GSDD Composite Score.

KEY RESULTS

Study TZP-102-CL-G003 enrolled 201 outpatients: females 72%; Caucasians 87%; type 2 diabetes 61%; insulin-dependent 65%; age mean ± SD 53 ± 11.3 years; HbA1c 7.8 ± 1.5%; GCSI 3.4 ± 0.7; GSDD Composite 3.6 ± 0.6; gastric T1/2 131 ± 32 min; n = 69 (10-mg), n = 66 (20-mg), n = 66 (placebo). Primary endpoint (GSDD): significant improvement in all arms, although not for TZP-102 vs placebo: mean change-from-baseline -1.7, -1.4, -1.5 (10-mg, 20-mg, placebo); Gastroparesis Cardinal Symptom Index -1.8, -1.6, -1.5, respectively. The OTE (all patients) at Week-12 was: Patient 3.7 ± 3.2 and Physician 3.6 ± 3.0 with median score for both of 5.0 = important on scale of improvement; individual MCID was 1.61 and 0.94 for group analyses, greater than expected. Study TZP-102-CL-G004 with similar demographic/disease characteristics was prematurely terminated for efficacy futility (n = 64 with Week-4 assessments).

CONCLUSIONS & INFERENCES

Efficacy of TZP-102 was not demonstrated compared with placebo in diabetic gastroparesis; however, there was substantial symptom improvement in all arms (ClinicalTrials.gov NCT01452815/NCT01664637).

Gastric electrical stimulation with Enterra therapy improves symptoms of idiopathic gastroparesis

BACKGROUND

Gastric electrical stimulation (GES) is a therapeutic option for intractable symptoms of gastroparesis (GP). Idiopathic GP (ID-GP) represents a subset of GP.

AIMS

A prospective, multicenter, double-blinded, randomized, crossover study to evaluate the safety and efficacy of Enterra GES in the treatment of chronic vomiting in ID-GP.

METHODS

Thirty-two ID-GP subjects (mean age 39; 81% F, mean 7.7 years of GP) were implanted with GES. The stimulator was turned ON for 1½ months followed by double-blind randomization to consecutive 3-month crossover periods with the device either ON or OFF. ON stimulation was followed in unblinded fashion for another 4.5 months. Twenty-five subjects completed the crossover phase and 21 finished 1 year of follow-up.

KEY RESULTS

During the unblinded ON period, there was a reduction in weekly vomiting frequency (WVF) from baseline (61.2%, P < 0.001). There was a non-significant reduction in WVF between ON vs OFF periods (the primary outcome) with median reduction of 17% (P > 0.10). Seventy-five percent of patients preferred the ON vs OFF period (P = 0.021). At 1 year, WVF remained decreased (median reduction = 87%, P < 0.001), accompanied by improvements in GP symptoms, gastric emptying and days of hospitalization (P < 0.05).

CONCLUSIONS & INFERENCES

(i) In this prospective study of Enterra GES for ID-GP, there was a reduction in vomiting during the initial ON period; (ii) The double-blind 3-month periods showed a non-significant reduction in vomiting in the ON vs OFF period, the primary outcome variable; (iii) At 12 months with ON stimulation, there was a sustained decrease in vomiting and days of hospitalizations.

A phase 2a, randomized, double-blind 28-day study of TZP-102 a ghrelin receptor agonist for diabetic gastroparesis

BACKGROUND

Gastroparesis causes significant morbidity and treatment options are limited. TZP-102 a novel, macrocyclic, selective, oral ghrelin receptor agonist, was evaluated in a randomized, double-blind, placebo-controlled trial in patients with diabetic gastroparesis.

METHODS

A total of 92 outpatients were randomized to once-daily administrations of 10-mg (n = 22), 20-mg (n = 21), 40-mg (n = 23) TZP-102 or placebo (n = 26). The primary endpoint was the change from baseline in gastric half-emptying time (T(½)) utilizing (13)C-breath test methodology and secondary endpoints included symptom improvement using patient-reported gastroparesis symptom scores (PAGI-SYM questionnaire) and patient and physician overall treatment evaluations (OTE).

KEY RESULTS

Gastric T½ changes were not statistically significant between TZP-102 and placebo after 28 days of treatment at any dose. Clinical improvements (-1.0 to -1.4 point mean decrease in symptom severity) occurred in the Gastroparesis Cardinal Symptom Index (GCSI) component of the PAGI-SYM, which was significant vs placebo for all TZP-102 doses combined. Improvements became evident after 1 week of treatment. Significantly, more patients given TZP-102 (any dose) had a 50% reduction in baseline GCSI score (28.8%vs 7.7% placebo). Safety profiles were similar across groups. All TZP-102 doses were well-tolerated with no adverse cardiac, weight, or glucose control outcomes.

CONCLUSIONS & INFERENCES

TZP-102 for 28 days, at doses of 10-40 mg once daily, was well-tolerated and resulted in a reduction in symptoms of gastroparesis. The lack of correlation between symptom improvement and gastric emptying change is consistent with previous studies in diabetic gastroparesis, and emphasizes the value of patient-defined outcomes in determining therapeutic benefit.

The addition of pyloroplasty as a new surgical approach to enhance effectiveness of gastric electrical stimulation therapy in patients with gastroparesis

BACKGROUND

Improvement of gastroparesis (GP) symptoms has been documented in patients treated with gastric electrical stimulation (GES), but acceleration of gastric emptying (GET) is unpredictable. The aim of our study was to evaluate the advantage of adding surgical pyloroplasty (PP) to GES for improvement of GET and control of symptoms in diabetes mellitus (DM), idiopathic (ID), and postvagotomy (P-V) GP.

METHODS

A total of 49 (17 - DM, 9 - ID, 23 - P-V) consecutive GP patients: 38 female; mean age 42 (21-73 years); mean weight 158 lbs (102-245), underwent GES implantation, and 26 (53%) additionally received PP. Total Symptoms Score, 4-h GET, adverse events (AEs), and days of hospitalizations were captured at baseline and at the last visit.

KEY RESULTS

The mean follow-up was 7 months. Total Symptoms Score in patients who received Enterra and PP or GES alone significantly improved compared to their baseline scores (P < 0.001). GET improved by 64% at 4 h (P < 0.001) in patients with Enterra and PP, compared to 7% observed after GES therapy alone (ns). The most impressive acceleration of GET was seen in the P-V group, who received both therapies (P = 0.004) and 8 (60%) of them normalized GET. No AEs accompanied the addition of PP to the Enterra surgery.

CONCLUSIONS & INFERENCES

(i) In drug-refractory GP the addition of PP to GES substantially accelerated GET; (ii) The GET response in P-V group was the most impressive; (iii) Significant symptom reductions were achieved by both procedures; and (iv) PP added to GES may sustain better long-term symptoms control particularly in the P-V setting.

Is symptom relief associated with reduction in gastric retention after gastric electrical stimulation treatment in patients with gastroparesis? A sensitivity analysis with logistic regression models

BACKGROUND

Enterra gastric electrical stimulation (GES) is an alternative treatment for gastroparesis (GP) when standard medical therapy fails. The aims of this study were to evaluate the association between total symptom score (TSS) and reduction in gastric retention (GR) after GES by GP etiology and to examine the sensitivity of the association to varying cutpoints used to define GR and TSS improvement.

METHODS

Gastric retention assessed with a standardized (99m) Tc radio-labeled egg meal and TSS measured by a five-point Likert scale in 221 GP patients treated with Enterra GES therapy for at least 1 year were analyzed. Bivariate chi-square test and multivariable logistic regression with all possible cutpoints were used to assess the consistency of association and quantitate the relationship across three GP etiologies.

KEY RESULTS

Symptom relief in diabetic GP was more likely attributable to GR reduction as indicated by the consistently significant odds ratios (P < 0.01) across all cutpoints. The association in idiopathic GP was inconclusive because odds ratios were sensitive to cutpoints with P-values ranging from 0.01 to 0.47. No association was found for patients with post surgical gastroparesis (P > 0.1 for all cutpoints). Patient age, gender, baseline TSS and baseline GR had no significant effect at 5% level on clinical improvement regardless of cutpoints for GR.

CONCLUSIONS & INFERENCES

Association between clinical improvements and GR reduction following GES treatment depends on patient etiology and was able to be demonstrated in diabetic GP. The association for idiopathic GP was inconclusive and no such association was found for post surgical GP across all possible cutpoint combinations.

Clinical-histological associations in gastroparesis: results from the Gastroparesis Clinical Research Consortium

BACKGROUND

Cellular changes associated with diabetic (DG) and idiopathic gastroparesis (IG) have recently been described from patients enrolled in the Gastroparesis Clinical Research Consortium. The association of these cellular changes with gastroparesis symptoms and gastric emptying is unknown. The aim of this study was to relate cellular changes to symptoms and gastric emptying in patients with gastroparesis.

METHODS

Earlier, using full thickness gastric body biopsies from 20 DG, 20 IG, and 20 matched controls, we found decreased interstitial cells of Cajal (ICC) and enteric nerves and an increase in immune cells in both DG and IG. Here, demographic, symptoms [gastroparesis cardinal symptom index score (GCSI)], and gastric emptying were related to cellular alterations using Pearson's correlation coefficients.

KEY RESULTS

Interstitial cells of Cajal counts inversely correlated with 4 h gastric retention in DG but not in IG (r = -0.6, P = 0.008, DG, r = 0.2, P = 0.4, IG). There was also a significant correlation between loss of ICC and enteric nerves in DG but not in IG (r = 0.5, P = 0.03 for DG, r = 0.3, P = 0.16, IG). Idiopathic gastroparesis with a myenteric immune infiltrate scored higher on the average GCSI (3.6 ± 0.7 vs 2.7 ± 0.9, P = 0.05) and nausea score (3.8 ± 0.9 vs 2.6 ± 1.0, P = 0.02) as compared to those without an infiltrate.

CONCLUSIONS & INFERENCES

In DG, loss of ICC is associated with delayed gastric emptying. Interstitial cells of Cajal or enteric nerve loss did not correlate with symptom severity. Overall clinical severity and nausea in IG is associated with a myenteric immune infiltrate. Thus, full thickness gastric biopsies can help define specific cellular abnormalities in gastroparesis, some of which are associated with physiological and clinical characteristics of gastroparesis.

Review article: cyclic vomiting syndrome in adults--rediscovering and redefining an old entity

BACKGROUND

Cyclic vomiting syndrome is a disorder characterised by recurrent episodes of severe nausea and vomiting separated by symptom-free periods.

AIMS

To review the history, epidemiology, clinical aspects, pathophysiology, diagnosis and treatments of adult cyclic vomiting syndrome as well as to identify areas for further clinical research and the unanswered questions in this field.

METHODS

We conducted a PubMed search using such keywords as cyclic vomiting syndrome; nausea; vomiting; pathophysiology; diagnosis; treatment; trigger factors; gastric emptying test; autonomic nerve function test; gastrointestinal hormones; outcome and natural history and combined this information with the knowledge and extensive clinical research and publications from the authors.

RESULTS

Available data show that in adult cyclic vomiting syndrome, severe epigastric and sometimes diffuse abdominal pain accompanies most cycles of nausea and vomiting interspersed with periods of symptomatic remission. Psychological disorders, specifically anxiety and depression are common, and gastric emptying is actually rapid in approximately 60% of patients and normal in the remainder. There is an impressive and sustained response to high-dose tricyclic antidepressants. In up to 15% who are regarded as poor responders to tricyclic antidepressants, a predictable profile can be identified related to co-existing psychological disorders, marijuana use, poorly controlled migraine headache or chronic narcotic use.

CONCLUSIONS

Cyclic vomiting syndrome in adults is an entity that is being increasingly recognised, but the need to educate Internists, Gastroenterologists and Emergency Department staff remains an ongoing challenge.

Autonomic nerve function in adult patients with cyclic vomiting syndrome

BACKGROUND

Cyclic vomiting syndrome (CVS) in adults is a disorder characterized by recurrent and stereotypic episodes of severe nausea and vomiting separated by symptom-free periods. Autonomic dysfunction has been a postulated mechanism for the pathogenesis of this disorder in children but has not been explored in adults.

METHODS

Our goals were to investigate autonomic nerve function in adult patients with CVS. The sympathetic nervous system was evaluated through postural changes in heart rate and blood pressure and sympathetic skin response in the hand and foot. The parasympathetic nervous system was tested through heart rate response to deep breathing [expiration/inspiration (E/I)], Valsalva and postural indices (30 : 15 ratio). All patients had a 4-h standard isotope labeled egg beater meal gastric emptying test (GET).

KEY RESULTS

Twenty-two adult (18 female), mean age 35 ± 11 (range 19-61 years), who met Rome III criteria for CVS were included. History of migraine headache was reported in three patients. Five (23%) had pediatric onset. Of 21 patients who completed the test, nine patients had 21 abnormalities detected in their autonomic nerve testing profile and the remaining 12 had normal autonomic function results. Orthostatic tachycardia was observed in two (mean heart rate increase 39 beats min(-1)) and a decline in blood pressure (BP) in three patients (mean BP drop 30/14 mmHg). Parasympathetic abnormalities were elicited in six patients with an abnormal response to deep breathing and E/I index <1.25. Sympathetic nerve dysfunction was reported in seven patients with absent sympathetic skin response in the foot and/or hand. Twelve (57%) of CVS group had rapid GET (<50% retention at 1 h). The frequency of abnormal autonomic nerve function was not significantly higher in rapid GET subgroup.

CONCLUSIONS & INFERENCES

(i) Autonomic nerve dysfunction is common in adult CVS patients, being observed in 43% of our cohort; (ii) Sympathetic abnormalities dominate; and (iii) Rapid gastric emptying, present in 57% of patients, did not correlate with autonomic testing results. These new data provide more insight into the pathophysiology of CVS in adults and help explain the spectrum of clinical manifestations observed in this entity.

Randomised clinical trial: ghrelin agonist TZP-101 relieves gastroparesis associated with severe nausea and vomiting--randomised clinical study subset data

BACKGROUND

Limited therapeutic options exist for severe gastroparesis, where severe nausea and vomiting can lead to weight loss, dehydration and malnutrition due to inadequate caloric and fluid intake. TZP-101 (ulimorelin) is a ghrelin receptor agonist that accelerates gastric emptying and improves upper gastrointestinal symptoms in diabetic patients with gastroparesis.

AIM

To assess effects of TZP-101 in diabetic gastroparesis patients with severe nausea/vomiting and baseline severity scores of ≥3.5 (range: 0-5) on the Gastroparesis Cardinal Symptom Index (GCSI) Nausea/Vomiting subscale.

METHODS

Patients were hospitalised and received four single daily 30-min infusions of one of six TZP-101 doses (range 20-600 μg/kg) or placebo. Efficacy was assessed by symptom improvement.

RESULTS

At baseline, 23 patients had a mean severity score for GCSI Nausea/Vomiting of 4.45±0.44. Statistically significant improvements over placebo occurred in the 80 μg/kg group for end of treatment changes from baseline in GCSI Nausea/Vomiting subscale (reduction in score of -3.82±0.76, P=0.011) and the GCSI Total score (-3.14±0.78, P=0.016) and were maintained at the 30-day follow-up assessment (-2.02±1.63, P=0.073 and -1.99±1.33, P=0.032 respectively). The proportion of days with vomiting was reduced significantly (P=0.05) in the 80 μg/kg group (mean of 1.2 days of vomiting for four treatment days) compared with placebo (mean of 3.2 days of vomiting across 4 treatment days).

CONCLUSIONS

TZP-101 substantially reduced the frequency and severity of nausea and vomiting as well as overall gastroparesis symptoms. The results are consistent with gastrointestinal motility effects of TZP-101, supporting further investigation of TZP-101 in the management of severe gastroparesis.

A Bayesian hierarchical assessment of gastric emptying with the linear, power exponential and modified power exponential models

BACKGROUND

Many studies assessed gastric retention over time utilizing different models, mostly with scintigraphic measures at varied endpoints from limited number of normal volunteers. With a standardized 4-h gastric emptying (GE) protocol, we compared model fit by the linear, power exponential (PE), and modified power exponential (MPE) models to contrast differences in GE among different groups based on clinical diagnosis and gender.

METHODS

We retrospectively collected 320 patient records with four consecutive hourly scintigraphic measures of percent intragastric residual at the Kansas University Medical Center. We obtained parameter estimates with the Bayesian hierarchical models using informative priors from previous research.

KEY RESULTS

The PE or MPE model captured the time dependent GE rate better than the linear model. The estimated GE rates more than doubled for those without gastroparesis compared to patients diagnosed with gastroparesis. Males tended to empty gastric content faster but were not significantly different from females at the 5% level.

CONCLUSIONS & INFERENCES

The point estimates and 95% credible interval for GE rates obtained with the PE and MPE models may provide an alternative diagnostic tool for clinicians since it utilizes gastric emptying scintigraphy measures at multiple endpoints which may be sensitive to different aspects of the disease. No agreement in lag phases was obtained by the three models based on respective definitions from previous researches, but similar results would be obtained with the PE and MPE models if both defined lag phase by back projecting the regression lines to the same gastric retention level.

Spectrum of gastric emptying patterns in adult patients with cyclic vomiting syndrome

BACKGROUND

Cyclic vomiting syndrome (CVS) in adults is a disorder characterized by recurrent and stereotypic episodes of severe nausea, vomiting and abdominal pain separated by symptom-free intervals. Both rapid and delayed gastric emptying (GE) have been observed but the reports involved small numbers of CVS patients.

METHODS

We performed a retrospective study of 92 adult patients who met Rome Ш diagnostic criteria for CVS between 2003 and 2009 at the Kansas University Medical Center. Gastric emptying was measured by a standardized scintigraphic method involving a low fat (2%) isotope labeled egg white meal of 250 Kcal, with anterior and posterior gastric imaging in the standing position obtained at 0, 1, 2, 4 h after meal ingestion. Rapid GE was defined as <50% isotope retention at 1st h and/or <30% at 2nd h and delayed GE as >10% at 4 h.

KEY RESULTS

Ninety two patients were analyzed: 47 males and 45 females mean of age 37 ± 12 years (range: 20-68 years). There were 27 patients with a personal history of migraine headache, 30 with history of marijuana use, 12 had diabetes mellitus (DM) and 10 had irritable bowel syndrome (IBS) as an accompanying diagnosis. Fifty four patients (59%) met criteria for rapid GE, 25 (27%) had normal GE and 13 (14%) had slow GE. Eighty percent of patients with co-existing IBS symptoms were identified as rapid. The subset with delayed emptying was often associated with narcotics use, DM and marijuana use (P < 0.05).

CONCLUSIONS & INFERENCES

(i) In adult CVS patients, GE is generally either rapid or normal. (ii) Cyclic vomiting syndrome is an important new etiology to explain the finding of rapid GE on a radionuclide test. (iii) The small subset of CVS patients (14%) whose GE was slow were explained by the role of narcotics and/or marijuana.

Safety and efficacy of ghrelin agonist TZP-101 in relieving symptoms in patients with diabetic gastroparesis: a randomized, placebo-controlled study

BACKGROUND

Gastroparesis, a chronic disorder of abnormal gastric motility, is common in patients with diabetes mellitus. A synthetic, selective ghrelin receptor agonist, TZP-101, is in clinical development for treatment of gastroparesis. This double-blind, randomized, placebo-controlled study evaluated the safety and efficacy of multiple TZP-101 doses in patients with moderate to severe symptomatic diabetic gastroparesis.

METHODS

Patients were admitted to the hospital and adaptively randomized to receive a single 30-min intravenous infusion of 20, 40, 80, 160, 320, or 600 μg kg(-1) TZP-101, (n = 57) or placebo, (n = 19) for four consecutive days. Symptoms were evaluated daily with the patient-rated Gastroparesis Cardinal Symptom Index (GCSI) and Gastroparesis Symptom Assessment (GSA). Clinicians rated gastroparesis symptoms on treatment day 4.

KEY RESULTS

  The 80 μg kg(-1) dose was identified as the most effective dose. On day 4, there was statistically significant improvement compared with placebo in the severity of GCSI Loss of Appetite and Vomiting scores for that dose group (P = 0.034 and P = 0.006). In addition, at the 80 μg kg(-1) dose, the proportion of patients with at least 50% improvement in vomiting score was significantly different (P = 0.019) compared with placebo. Meal-related GSA scores for Postprandial fullness were significantly improved in the 80 μg kg(-1) TZP-101 group compared with placebo (P = 0.012). Clinicians rated the 80 μg kg(-1) group better improved than placebo for overall symptom assessment (P = 0.047). Safety profiles were similar in the placebo and TZP-101 groups and all doses were well-tolerated.

CONCLUSIONS & INFERENCES

TZP-101 appears to be safe, well-tolerated, and effective at acutely addressing several gastroparesis symptoms.

Motility of the antroduodenum in healthy and gastroparetics characterized by wireless motility capsule

BACKGROUND

The wireless motility capsule (WMC) measures intraluminal pH and pressure, and records transit time and contractile activity throughout the gastrointestinal tract. Our hypothesis is that WMC can differentiate antroduodenal pressure profiles between healthy people and patients with upper gut motility dysfunctions. This study aims to analyze differences in the phasic pressure profiles of the stomach and small intestine in healthy and gastroparetic subjects.

METHODS

Data from 71 healthy and 42 gastroparetic subjects were analyzed. The number of contractions (Ct), area under the pressure curve and motility index (MI = Ln (Ct *sum amplitudes +1)) were analyzed for 60 min before gastric emptying of the capsule (GET), (gastric window) and after GET (small bowel window) and results between groups were compared with the Wilcoxon rank sum test.

KEY RESULTS

Significant differences were observed between healthy and gastroparetic subjects for Ct and MI (P < 0.05). Median values of the motility parameters in gastric window were Ct = 72, MI = 11.83 for healthy and Ct = 47, MI = 11.12 for gastroparetics. In the small bowel, median values were Ct = 144.5, MI = 12.78 for healthy and Ct = 93, MI = 12.12 for gastroparetics. Diabetic subjects with gastroparesis showed significantly lower Ct and MI compared with healthy subjects in both gastric and small bowel windows while idiopathic gastroparetic subjects did not show significant differences.

CONCLUSIONS & INFERENCES

The WMC is able to differentiate between healthy and gastroparetic subjects based on gastric and small bowel motility profiles.

Gastroparesis and functional dyspepsia: excerpts from the AGA/ANMS meeting

BACKGROUND

Despite the relatively high prevalence of gastroparesis and functional dyspepsia, the aetiology and pathophysiology of these disorders remain incompletely understood. Similarly, the diagnostic and treatment options for these two disorders are relatively limited despite recent advances in our understanding of both disorders.

PURPOSE

This manuscript reviews the advances in the understanding of the epidemiology, pathophysiology, diagnosis, and treatment of gastroparesis and functional dyspepsia as discussed at a recent conference sponsored by the American Gastroenterological Association (AGA) and the American Neurogastroenterology and Motility Society (ANMS). Particular focus is placed on discussing unmet needs and areas for future research.

Mechanisms of symptomatic improvement after gastric electrical stimulation in gastroparetic patients

The aims were to investigate the effects of gastric electrical stimulation (GES) on autonomic function, gastric distention and tone, and central control mechanisms in gastroparetic patients. Ten gastroparetic patients refractory to standard medical therapy participated in this study and data were collected at baseline, within two weeks before surgery for implantation of GES system, and at follow-up sessions between 6 and 12 weeks after GES therapy was initiated. In each session, electrocardiogram, electrogastrogram (EGG) and gastric barostat measurements were conducted before and after a caloric liquid meal. Positron Emission Tomography (PET) brain scans were performed on a separate day. During GES therapy there was a significant increase in the discomfort threshold for mean pressure from 21 mmHg at baseline to 25 mmHg at follow-up, and for mean volume from 561 mL to 713 mL. A significant increase in the postprandial EGG power (amplitude) was observed between baseline and follow up. The sympathovagal balance was significantly decreased after GES therapy, indicating a significant increase in vagal activity. The cumulative PET data showed an increase in quantitative radioactive counts relative to the standardized data base in both the thalamic and caudate nuclei after chronic GES therapy. We conclude that our data suggest that the symptomatic improvement achieved by GES in gastroparesis is best explained by activation of vagal afferent pathways to influence CNS control mechanisms for nausea and vomiting accompanied by enhanced vagal efferent autonomic function and decreased gastric sensitivity to volume distention which enhances postprandial gastric accommodation.

Who are the nonresponders to standard treatment with tricyclic antidepressant agents for cyclic vomiting syndrome in adults?

BACKGROUND

Cyclic vomiting syndrome in adults is a disorder characterized by recurrent and stereotypic episodes of severe nausea and vomiting separated by symptom-free periods.

AIMS

To investigate the demographic and clinical characteristics of adult cyclic vomiting syndrome patients not responding to standard tricyclic antidepressant (TCA) therapy.

METHODS

A total of 132 adults (62 men) with cyclic vomiting syndrome were followed for a mean of 1.6 years. Of these, 17 (eight men) patients were identified as nonresponders based on the criteria of unchanged, increased or minimally changed (<25%) frequency/duration of episodes and/or emergency department visits/hospitalizations. Demographic and clinical characteristics at baseline and annually up to 4 years were investigated.

RESULTS

The nonresponders were receiving TCAs at an average dose of 90 mg/day compared to a mean dose of 85 mg/day in responders. Compared with the responders, the nonresponders were significantly more likely to have a history of migraine (P < 0.05); co-existing psychological disorders (P < 0.05); chronic marijuana use (P < 0.05) and reliance on narcotics for pain control between cyclic vomiting syndrome episodes (P < 0.05).

CONCLUSIONS

(1) Nonresponse to standard therapy in adult cyclic vomiting syndrome patients occurs in approximately 13% and is not explained by under dosing with TCA therapy. (2) The main risk factors for nonresponse are: co-existing migraine headache, psychiatric disorder, chronic narcotic and marijuana use, which should be addressed aggressively when symptom exacerbations continue during attempts to induce remission in cyclic vomiting syndrome with high-dose TCA therapy.

Association of the status of interstitial cells of Cajal and electrogastrogram parameters, gastric emptying and symptoms in patients with gastroparesis

Our goal was to investigate associations between the status of interstitial cells of Cajal (ICC) and electrogastrogram (EGG) parameters, gastric emptying and symptoms in a large cohort of patients with gastroparesis. Forty-one patients with refractory gastroparesis who were referred for gastric electrical stimulation (GES) underwent full thickness gastric (antrum) biopsy during the surgery to place the GES device. The biopsy samples were stained with c-kit and scored for the presence of ICC based on criteria obtained from 10 controls. All patients underwent EGG recordings, a 4-h standardized scintigraphic gastric emptying study and symptom assessment prior to the surgery. Based on antral biopsy, 15 patients (36%) had almost no ICC (ICC- group) and 26 patients had adequate cell numbers (ICC+ group). EGG recordings in the ICC- group displayed significantly less normal slow waves than in the ICC+ group both in the fasting and fed states. Tachygastria in the ICC- group was significantly more than in the ICC+ group both in the fasting (32 +/- 8%vs 11 +/- 2%) and fed states (27 +/- 9%vs 12 +/- 2%). There was no statistical difference in gastric emptying, symptom severity of gastroparesis, aetiology, age and gender between the two groups. Severely depleted ICC occurs in up to 36% of gastroparetic patients and significantly correlates with an abnormal EGG. Severely depleted ICC does not correlate with the severity of gastroparesis as assessed by gastric emptying or symptom status but did result in a poorer symptomatic response to GES. These data suggest that the EGG may have a role for predicting ICC status during clinical evaluation of gastroparetic patients.

Are pediatric and adult-onset cyclic vomiting syndrome (CVS) biologically different conditions? Relationship of adult-onset CVS with the migraine and pediatric CVS-associated common mtDNA polymorphisms 16519T and 3010A

Pediatric cyclic vomiting syndrome (CVS) is associated with a high prevalence of co-morbid migraine and other functional disorders, and with two adult migraine-associated mitochondrial DNA (mtDNA) polymorphisms: 16519T and 3010A. These potential associations have not been studied in adult CVS. The objective of this study is to determine the prevalence of 16519T and 3010A mtDNA polymorphisms and other functional disorders in adult CVS patients. Adults with CVS recruited from the University of Kansas meeting Rome III criteria and a population control group completed a self-reported survey that included questions relating to the diagnostic criteria for several functional disorders. DNA was isolated from blood or saliva and genotyping was performed by standard methodologies. Adult CVS subjects, compared to controls, had significantly more symptoms consistent with several other functional disorders. 16519T was present in 22/31 cases (71%) of child-onset (<12 years) and 9/31 (29%) cases of adult-onset (18+ years) CVS (P = 0.01), vs 27% of controls. Among subjects with 16519T, 3010A was present in 30% of child-onset vs 0% of adult-onset CVS (P = 0.05) and 2% of controls. The conclusions drawn were: (i) unlike pediatric CVS, adult CVS is not associated with the 16519T and 3010A mtDNA polymorphisms, suggesting a degree of genetic distinction and (ii) similar to the pediatric setting, adult CVS is associated with a substantial burden of co-morbid functional disorders.

Effect of oxygen content on the magnetic properties of multiferroic YMn(2)O(5+δ)

The effect of oxygen content on magnetic properties in the multiferroic YMn(2)O(5+δ) system was investigated with samples prepared under different oxygen pressures. Our results show that, with increasing oxygen content, the magnetic response changes from being dominated by the anomaly at ∼45 K to the one around 20 K. However, specific heat measurements and neutron powder diffraction studies indicate that the presence of the magnetic transition at ∼45 K is independent of oxygen content. The results suggest that oxygen nonstoichiometry can be one important degree of freedom in manipulating the multiferroic properties.

Probing fractal magnetic domains on multiple length scales in Nd2Fe14B

Using small-angle neutron scattering, we demonstrate that the complex magnetic domain patterns at the surface of Nd2Fe14B, revealed by quantitative Kerr and Faraday microscopy, propagate into the bulk and exhibit structural features with dimensions down to 6 nm, the domain wall thickness. The observed fractal nature of the domain structures provides an explanation for the anomalous increase in the bulk magnetization of Nd2Fe14B below the spin-reorientation transition. These measurements open up a rich playground for studies of fractal structures in highly anisotropic magnetic systems.

Association between changes in symptoms and gastric emptying in gastroparetic patients treated with gastric electrical stimulation

To investigate whether there is an association between gastric emptying rate and symptom improvement in gastroparetic patients treated with gastric electrical stimulation (GES), we retrospectively reviewed 63 gastroparetic patients who received GES therapy for at least 1 year. Patient characteristics, seven upper gastrointestinal (GI) symptoms and 4-h standardized gastric emptying test (GET) were evaluated at baseline and at 1 year of GES. All symptoms were significantly reduced (P < 0.001). Mean gastric retention was reduced by 7% (P = 0.102) for measurement at 4 h. Of the 63 patients, 14 had their GET normalized and 49 remained delayed after 1 year. Normalized GET patients had a similar symptom improvement as those whose GET remained delayed. Of all upper GI symptoms, the improvements in vomiting (P = 0.04), nausea (P = 0.002) and epigastric pain (P = 0.001) were significantly correlated with reduction in 4-h gastric retention between baseline and 12 months of GES therapy for patients with normalized gastric emptying but there were no correlations with any symptoms and change in gastric emptying for those patients who remained delayed. In summary, overall gastric emptying is not significantly accelerated at 4 h after successful symptomatic improvement with GES but nausea, vomiting and epigastric pain can be correlated with normalization of GET in a subset of patients.

Cyclic vomiting syndrome in adults

Cyclic vomiting syndrome (CVS) was initially described in children but can occur in all age groups. Cyclic vomiting syndrome is increasingly recognized in adults. However, the lack of awareness of CVS in adults has led to small numbers of diagnosed patients and a paucity of published data on the causes, diagnosis and management of CVS in adults. This article is a state-of-knowledge overview on CVS in adults and is intended to provide a framework for management and further investigations into CVS in adults.

Comparison of gastric emptying of a nondigestible capsule to a radio-labelled meal in healthy and gastroparetic subjects

BACKGROUND

Gastric emptying scintigraphy (GES) using a radio-labelled meal is used to measure gastric emptying. A nondigestible capsule, SmartPill, records luminal pH, temperature, and pressure during gastrointestinal transit providing a measure of gastric emptying time (GET).

AIMS

To compare gastric emptying time and GES by assessing their correlation, and to compare GET and GES for discriminating healthy subjects from gastroparetics.

METHODS

Eighty-seven healthy subjects and 61 gastroparetics enrolled with simultaneous SmartPill and GES. Fasted subjects were ingested capsule and [(99m)Tc]-SC radio-labelled meal. Images were obtained every 30 min for 6 h. Gastric emptying time and percentage of meal remaining at 2/4 h were determined for each subject. The sensitivity/specificity and receiver operating characteristic analysis of each measure were determined for each subject.

RESULTS

Correlation between GET and GES-4 h was 0.73 and GES-2 h was 0.63. The diagnostic accuracy from the receiver operating characteristic curve between gastroparetics and healthy subjects was GET = 0.83, GES-4 h = 0.82 and GES-2 h = 0.79. The 300-min cut-off time for GET gives sensitivity of 0.65 and specificity of 0.87 for diagnosis of gastroparesis. The corresponding sensitivity/specificity for 2 and 4 h standard GES measures were 0.34/0.93 and 0.44/0.93, respectively.

CONCLUSION

SmartPill GET correlates with GES and discriminates between healthy and gastroparetic subjects offering a nonradioactive, standardized, ambulatory alternative to scintigraphy.

Clinical trial: effect of mitemcinal (a motilin agonist) on gastric emptying in patients with gastroparesis - a randomized, multicentre, placebo-controlled study

BACKGROUND

Mitemcinal is an orally active motilin agonist that could potentially improve gastric emptying.

AIM

To investigate the effect of mitemcinal on gastric emptying in patients with idiopathic and diabetic gastroparesis.

METHODS

In a randomized, double-blind design, 106 patients were randomized into four dosing regimens (22 to placebo and 21 each to mitemcinal 10 mg, 20 mg, 30 mg bid or 20 mg tid) for 28 days. A standardized scintigraphic gastric emptying test was performed at screening and again after completing the 4-week protocol.

RESULTS

All doses of mitemcinal showed prokinetic activity. A significant improvement in meal retention at 240 min was noted even in the lowest dose group with the greatest improvement observed with 30 mg bid group (75% vs. 10% in placebo group). Diabetic patients responded better than the idiopathic subgroup. In diabetic patients, blood glucose at 1 h after a meal showed dose-dependent elevation. Although gastroparetic symptoms improved with both mitemcinal and placebo, the prominent placebo effect was not statistically exceeded by mitemcinal. Baseline scintigraphy results exhibited no clear correlation between the severity of gastroparetic symptoms and the status of gastric emptying.

CONCLUSION

Mitemcinal is capable of accelerating gastric emptying in both diabetic and idiopathic patients with gastroparesis.

Efficacy of mitemcinal, a motilin agonist, on gastrointestinal symptoms in patients with symptoms suggesting diabetic gastropathy: a randomized, multi-center, placebo-controlled trial

BACKGROUND

Mitemcinal, an oral motilin agonist, accelerates gastric emptying.

AIM

To investigate if mitemcinal was superior to placebo in relief of symptoms attributed to gastroparesis.

METHODS

In a randomized, double-blind design, 392 insulin-requiring diabetics with symptoms attributable to gastroparesis were treated for 3 months with placebo, mitemcinal 5 or 10 mg bid. On a weekly basis, patients assessed whether there was adequate relief of their gastroparesis symptoms. Patients were classified as Complete Responders (CR) if there were three consecutive positive monthly responses, which required at least 50% of their weekly responses in a month being positive. An Overall Responder (OR) had at least 75% positive weekly responses for the whole treatment period.

RESULTS

Mitemcinal 10 mg produced a significantly better response rate than placebo with a 10.6% increase in the OR (P < 0.05 vs. placebo). Mitemcinal 10 mg also produced statistically significant increases in the CR and OR in the subgroup identified by baseline body mass index (<35 kg/m(2)) and haemoglobin A(1c) (<10%) (P < 0.01 vs. placebo). Adverse events did not differ from placebo frequency levels.

CONCLUSIONS

Mitemcinal can induce a statistically significant response to treatment in a subset of diabetic gastroparesis where future prokinetic clinical trials should be focused.

Clinical, psychiatric and manometric profile of cyclic vomiting syndrome in adults and response to tricyclic therapy

Our goal was to investigate 31 adult patients (mean age 29 years, range 18-62 years) meeting Rome II criteria for cyclic vomiting syndrome (CVS). All subjects completed a clinical questionnaire, a Hamilton Rating Scale for Anxiety (HAM-A) and Zung Depression Inventory. Gastric emptying time was assessed in 30 subjects and electrogastrogram (EGG) in 11 between acute attacks. Twenty-seven patients treated with amitriptyline completed a follow-up questionnaire. The mean age of onset of the patients was 30 years (range 14-53 years) and cycles of nausea and vomiting were accompanied by often-severe epigastric and diffuse abdominal pain. A typical attack ranged from 1 to 14 days, with the majority being 4-6 days. The HAM-A revealed that 84% had an anxiety disorder, and based on Zung Depression Inventory 78% suffered from mild-to-severe depression. Only 4 (13%) patients reported migraine, but 14 had a family history of migraine. Gastric emptying time was rapid in 23 (77%), normal in 4 and delayed in 3. The EGG was abnormal in 7 of 11 patients, with 4 having tachygastria. Of 13 patients using marijuana, 7 had symptom relief, while 2 had resolution of CVS after stopping use. The overall treatment experience in the 24 patients receiving amitriptyline up to 1 mg kg(-1) day(-1) for at least 3 months indicated that 93% had decreased symptoms and 26% achieved full remission. Cyclic vomiting syndrome in adults has the following hallmarks: prominence of accompanying abdominal pain and increased prevalence of anxiety and depression, rapid gastric emptying and tachygastric EGG, and successful suppression of attacks by chronic amitriptyline therapy.

Results of small intestinal bacterial overgrowth testing in irritable bowel syndrome patients: clinical profiles and effects of antibiotic trial

PURPOSE

Small intestinal bacterial overgrowth (SIBO) may coexist with irritable bowel syndrome (IBS) and eradication therapy has been reported as effective in reducing IBS symptoms. Aims of this study were to: (1) Assess the clinical profiles of IBS patients, who underwent breath testing with a glucose substrate--glucose breath test (GBT); (2) Evaluate hydrogen and methane parameters in various IBS groups; (3) Assess the role of inhibition of gastric acid in contributing to SIBO; (4) Investigate efficacy and safety of non-absorbable antibiotic rifamixin for eradication and symptom relief.

METHODS

204 IBS patients met the ROME II criteria for IBS (170F & 34M; mean age 46.4; range 18-88) and underwent GBT. 8 of these patients with positive GBT were treated with rifaximin 200 mg, 4 times a day for 1 month and symptom assessments and GBT were repeated.

RESULTS

93 (46%) had a positive GBT. 68 (73%) of these 93 IBS-diarrhea dominant (IBS-D), 12 (13%) were constipation dominant (IBS-C) and 13 (14%) IBS with alternating bowel pattern. 48% of SIBO positive patients were receiving PPI therapy compared to 40% of IBS patients with negative GBT. 61 (66%) produced only hydrogen, 27 (29%) methane only, and 5 (5%) both-hydrogen and methane. There were more methane producers in IBS-C then IBS-D group (58% vs 28%) while IBS-D had more hydrogen formers (71% vs 42%). 8 patients with SIBO (7F & IM; mean age 55, range 31-85) received rifamixin 800 mg/day. Repeat GBT was normal in 6 (75%), 1 patient (12.5%) normalized according to hydrogen criteria but methane remained positive. Symptoms score improved in 7 (87.5%) patients and no adverse events were noted.

CONCLUSIONS

(1) SIBO was present in nearly half of this large cohort of IBS patients based on the results of GBT; (2) Chronic PPI use was not associated with SIBO; (3) Methane formers on the GBT are more likely to be constipated; (4) Rifaximin is effective in treatment of SIBO in IBS and controlled trials are warranted.

Treatment of gastroparesis: a multidisciplinary clinical review

This clinical review on the treatment of patients with gastroparesis is a consensus document developed by the American Motility Society Task Force on Gastroparesis. It is a multidisciplinary effort with input from gastroenterologists and other specialists who are involved in the care of patients with gastroparesis. To provide practical guidelines for treatment, this document covers results of published research studies in the literature and areas developed by consensus agreement where clinical research trials remain lacking in the field of gastroparesis.

Role of bile acids, prostaglandins and COX inhibitors in chronic esophagitis in a mouse model

AIM: To develop a new experimental model of esophagitis that serves a complementary tool to clinical investigation in an insight into the mechanism of the damage to the esophagus mucosa by aggressive factors, and role of COX inhibitors in this process.

METHODS: The study was conducted in 56 male mice. Animals were divided into seven groups: (1) perfused with HCl, (2) perfused with HCl and physiologic concentration of pepsin (HCl/P), (3) perfused with similar HCl/P solution enriched with conjugated bile acids (glycho- and tauro-sodium salts) designated esophageal infusion catheter under the general anesthesia, (4) perfused as in group 2 treated with indometacin, (5) perfused as in group 2 treated with NS-398, (6) perfused as in group 3 treated with indometacin, and (7) perfused as in group 3 treated with NS-398. The esophagus was divided into 3 parts: upper, middle and lower. The PGE2 concentration was measured in all parts of esophagus using RIA method. Esophagus of sacrificed animals was macroscopically evaluated using a low power dissecting microscope (20×). Specimens, representing the most frequently seen changes were fixed, stained with H&E and assessed microscopically using the damage score, and inflammatory score.

RESULTS: The macroscopic changes were significantly severer in HCl/P than those in HCl animals (77%) and in HCl/P/BA group (43%). In HCl/P NS-398 group we noticed significantly less changes than those in not treated group (42%) and in analogical group treated with indomethacine (45%). In HCl/P/BA INDO group we observed significantly severer changes than that in not treated group (52%). We noticed less changes in HCl/P NS-398 than that in group with indomethacine (46%). In HCl/P/BA NS-398 group we had less changes than that in indometacin group (34%). The microscopic changes observed in HCl/P/BA INDO group were severer than that in not treated group (48%). Esophagitis index in HCl group was significantly lower than in HCl/P and also HCl/P/BA group (32% and 33 %). In HCl/P/BA/INDO group the esophagitis surface was larger than that in not treated group (33%). In HCL/P group the surface of esophagus with ulceration was significantly larger (10-fold) than that in HCl/P/BA group. The PGE2 concentration was significantly higher in HCl/P group than in HCl/P/BA group. The PGE2 concentration in lower part of esophagus was also significantly higher in middle than those in HCl and HCl/P/BA groups. In upper part of esophagus the PGE2 concentration was significantly higher in HCl/P/BA group than that in group treated with indomethacine (46%). We also observed higher PGE2 concentration in middle part of esophagus in HCl/P/BA group than those in group treated with indomethacine and in group treated with indometacin and NS-398 (by 52% and 43% respectively).

CONCLUSION: Pepsin is the pivotal factor in the development of chronic esophageal injury. Bile acids diminish chronic esophageal injury induced by HCl/P, indicating its potential negative impact on pepsin proteolytic potential, pivotal for mucosal injury in low pH. The role of selective COX inhibitors is still unclear, and needs more investigations. This novel chronic experimental esophagitis is an excellent model for further study on the role of cytokines in genetically modified animals.

Symptom responses, long-term outcomes and adverse events beyond 3 years of high-frequency gastric electrical stimulation for gastroparesis

The aims were to determine symptom responses and long-term outcomes in gastroparetic patients receiving gastric electrical stimulation (GES) therapy beyond 3 years by presenting per protocol analysis and intention-to-treat (ITT) analysis. Data collected at baseline, 1 year and beyond 3 years in 55 patients included total symptom scores (TSS), nutritional status, weight, hospitalizations, the use of prokinetic and/or antiemetic medications, HbA1c in diabetics and adverse events. Of the 55 patients, 10 died of non-pacemaker-related complications, six had the devices removed and two could not be reached. The remaining 37 patients had the device activated for a mean of 45 months. Both per protocol and ITT analysis demonstrated that TSS, hospitalization days and the use of medications were all significantly reduced at 1 year and were sustained beyond 3 years. Average TSS decreased by 62.5% for the 37 patients completing 3 years of GES. At implantation, 15/37 patients required nutritional support and only five continued beyond 3 years. Mean HbA1c level in diabetics was significantly reduced from 9.5 to 7.9% at 3 years. We conclude that a significant improvement in symptoms and all measures of clinical outcome can be maintained for greater than 3 years with GES in patients with refractory gastroparesis.

Efficiency and efficacy of multi-channel gastric electrical stimulation

Gastric electrical stimulation (GES) using single channel has been under investigation for its therapeutic potential for gastroparesis. The aim of this study was to study the efficacy and efficiency of multi-channel GES in accelerating gastric emptying in dogs. The study was performed in eight dogs, and gastric emptying of liquid was assessed in three randomized sessions of control, one-channel GES and four-channel GES. It was found that (i) GES of both one-channel and four-channel was able to completely entrain the slow waves in the entire stomach. However, the stimulation energy required by four-channel GES was only 1% of that required by one-channel GES. (ii) Four-channel, but not one-channel, GES significantly and substantially accelerated gastric emptying. An increase of 121.0 and 93.9% was noted with four-channel GES at 30 and 60 min after the meal, respectively. It was concluded that four-channel GES is substantially more efficient and effective than conventional single-channel GES in improving gastric emptying. It is worthy to explore its therapeutic potential for gastroparesis in clinical settings.

Effect of high-frequency gastric electrical stimulation on gastric myoelectric activity in gastroparetic patients

The aim of this study was to investigate the effect of gastric electrical stimulation (GES) on gastric myoelectric activity (GMA) and to identify possible mechanisms that could help explain how high-frequency GES is effective in treating nausea and vomiting associated with gastroparesis. Fifteen gastroparetic patients who received high-frequency GES were enrolled. Two pairs of temporary pacing wires were implanted on the serosa of the stomach along the greater curvature during surgery for placement of the permanent stimulation device. Two-channel serosal recordings of GMA before and during GES were measured. A gastric emptying test and severity of nausea and vomiting were assessed at baseline and at 3 months of GES. Power spectral and cross correlation analyses revealed that impaired propagation of slow waves (50%), tachygastria (30%) and abnormal myoelectric responses to a meal (50%) were the main abnormalities observed at baseline. GES with a high frequency significantly enhanced the slow wave amplitude and propagation velocity, and resulted in a significant improvement in nausea and vomiting but did not entrain the gastric slow wave or improve gastric emptying after 3 months of GES.

Higher carotid-radial pulse wave velocity in healthy offspring of patients with Type 2 diabetes

AIMS

To determine whether carotid-radial pulse wave velocity (crPWV), a simple non-invasive measurement of muscular artery structure and function, is increased in offspring of patients with Type 2 diabetes compared with well-matched controls with no family history of diabetes. Serum levels of intercellular adhesion molecule-1 (sICAM-1) were also examined.

METHODS

Offspring (n = 19, M = 8) were recruited via contact with patients attending clinics. Controls (n = 19, M = 8) were recruited by advertisement. crPWV was measured using COMPLIOR. Blood pressure and heart rate were determined and fasting blood taken for measurement of metabolic and endothelial parameters.

RESULTS

Offspring and controls were well matched [mean (sd)] for age [33.1 (9.6) vs. 32.8 (9.5) years], body mass index [24.8 (4.9) vs. 24.3 (3.4) kg/m2], waist circumference [78.3 (2.3) vs. 76.3 (2.5) cm], and systolic blood pressure [120 (9.3) vs. 119 (14.2) mmHg]. crPWV was 10% higher in the offspring [9.94 (1.3) m/s] compared with controls [9.01 (1.2) m/s, P = 0.02] despite similar pulse pressure [52 (10.5) vs. 53.5 (9.3) mmHg] and resting heart rate [71 (8.7) vs. 69 (14.0) beats/min]. They also showed a trend toward higher sICAM-1 [217 (55) vs. 188 (40) ng/ml, P = 0.07] concentrations which were also strongly correlated to crPWV in offspring (r = 0.63, P = 0.004).

CONCLUSIONS

Vascular dysfunction in the form of increased muscular artery stiffness is present from an early stage in subjects at higher risk of developing diabetes. This may be secondary to impaired activation of endothelial signalling pathways in the context of inherited insulin resistance.

Secretory function of the esophageal mucosa in opossum: the role of cholinergic, peptidergic and histaminergic pathways

PURPOSE

Esophageal histology in the opossum reveals numerous submucosal mucous glands closely resembling those commonly found in humans. The aim of the study was to examine the secretion of these glands using the commonest secretagogues.

MATERIAL AND METHODS

The esophageal lumen in 5 male opossums was continuously perfused with saline during sixteen consecutive 5 min perfusion periods. After four initial equilibrating periods, each animal was injected (s.c.) with pentagastrin (6 microg/kg), bethanechol chloride (100 microg/kg) or histamine dihydrochloride (0.5 mg/kg). All sixteen (5 min) perfusates were assayed for protein by Lowry, mucin by PAS and viscosity using a cone/plate digital viscometer. Results were expressed as mean +/- SE. Statistical analysis was performed using paired Student's t-test.

RESULTS

Administration of bethanechol resulted in a significant increase in esophageal mucin release from 2.4 +/- 0.4 to 8.0 +/- 1.2 microg/cm2/min (p < 0.01); enhancement of protein output from 8.9 +/- 2.0 to 20.4 +/- 2.9 microg/cm2/min (p < 0.01) and potentiation of specific viscosity from 7.5 +/- 0.6 to 14.4 +/- 0.8 (p < 0.01). Pentagastrin-induced release of mucin reached the maximal value of 5.5 +/- 0.7 microg/cm2/min (p < 0.01), protein output increased to 20.0 +/- 2.7 (p < 0.01) and viscosity expanded to 11.7 +/- 0.9 (p < 0.05). Histamine evoked an increase in mucin release to 3.9 +/- 0.4 microg/cm2/min (p < 0.01), protein output to 24.1 +/- 3.3 microg/cm2/min (p < 0.01) and viscosity to 12.8 +/- 1.1 (p < 0.05).

CONCLUSIONS

The significant influence of cholinergic, histaminergic and peptidergic stimulation on physical and chemical properties of the esophageal secretion provides evidence for the role of these pathways in the pathophysiology of the esophageal mucosa.