Fluorescence cholangiography during laparoscopic cholecystectomy: a feasibility study on early biliary tract delineation

BACKGROUND

Laparoscopic cholecystectomy (LC) is one of the most commonly performed laparoscopic procedures. Bile duct injury is a rare but serious complication during this procedure, mostly caused by misidentification of the extrahepatic bile duct anatomy. Intraoperative cholangiography may be helpful to reduce the risk of bile duct injury; however, this is not a common procedure worldwide. Near-infrared fluorescence cholangiography (NIRFC) using indocyanine green (ICG) is a promising alternative for the identification of the biliary tree. This prospective observational study was designed to assess the feasibility and image quality of intermittent NIRFC during LC, using a newly developed laparoscopic fluorescence system.

METHODS

Consecutive patients undergoing elective LC were included and received a single intravenous injection of ICG directly after induction of anesthesia. During dissection of the base of the gallbladder and the cystic duct, the extrahepatic bile ducts were visualized by using a dedicated laparoscope, which offers both conventional state-of-the-art imaging and fluorescence imaging. Intraoperative recognition of the biliary structures was registered at set time points, as well as the establishment of the critical view of safety.

RESULTS

Fifteen patients were included between December 2011 and May 2012. ICG was visible in the liver and bile ducts within 20 min after intravenous administration and remained for approximately 2 h, using the fluorescence mode of the laparoscope. The common bile duct and cystic duct could be clearly identified at an early stage of the operation and, more important, significantly earlier than with the conventional camera mode. No per- or postoperative complications occurred as a consequence of ICG use.

CONCLUSIONS

Intermittent fluorescence imaging using a newly developed laparoscope and preoperative administration of ICG seems a useful aid in accelerating visualization of the extrahepatic bile ducts during laparoscopic cholecystectomy.

Increased proton pump inhibitor and NSAID exposure in irritable bowel syndrome: results from a case-control study

Background

Patients with irritable bowel syndrome (IBS) seen by a gastroenterologist often utilize medications that may alter intestinal homeostasis. The question arises whether exposure to these drugs is associated with the development of IBS symptoms. Aim of this study was therefore to assess the use of PPIs and NSAIDs in patients with IBS versus controls.

Methods

Cases of IBS from the last 5 years were reviewed. All patients having had at least one prescription for a particular drug (PPIs, NSAIDs, SSRIs, diuretics, ACE inhibitors) in the 6 months prior to the time of initial symptom onset were considered exposed. The control group consisted of individuals randomly selected from the general population.

Results

287 cases of IBS were retrieved for analysis together with 287 age and sex-matched controls. Exposure to PPIs and NSAIDs was significantly higher in IBS patients, whereas no association between ACE inhibitor use and IBS was found. PPIs were not significantly associated when excluding patients with gastrointestinal reflux disease or functional dyspepsia. Exposure to SSRIs was also positively associated with IBS, but only when patients with psychiatric comorbidity were included in the analyses.

Conclusions

Medications that may alter intestinal homeostasis such as NSAIDs and PPIs were more frequently used in IBS patients compared to controls. This association might be relevant for everyday clinical practice, but it is remains to be elucidated whether this association is of etiological nature.

Rectal hypersensitivity as hallmark for irritable bowel syndrome: defining the optimal cutoff

BACKGROUND

Visceral hypersensitivity is a frequently observed hallmark of irritable bowel syndrome (IBS). Studies have reported differently about the presence of visceral hypersensitivity in IBS resulting from lack of standardization of the barostat procedure and due to different criteria used to assess hypersensitivity. We aimed to calculate the optimal cutoff to detect visceral hypersensitivity in IBS.

METHODS

A total of 126 IBS patients and 30 healthy controls (HC) were included for assessment of visceroperception by barostat. Pain perception was assessed on a visual analogue scale (VAS). ROC-curves were used to calculate optimal discriminative cutoff (pressure and VAS-score) between IBS patients and HC to define hypersensitivity. Furthermore, pain perception to distension sequences below the pressure threshold for hypersensitivity was defined as allodynia.

KEY RESULTS

Irritable bowel syndrome patients showed increased visceroperception compared to HC. Thresholds for first sensation and first pain were lower in IBS patients VS HC (P < 0.01). ROC-curves showed optimal discrimination between IBS patients and HC at 26 mmHg with a VAS cutoff ≥20 mm. Using this criterion, hypersensitivity percentages were 63.5% and 6.6% in IBS patients and HC, respectively. No significant differences were observed between IBS subtypes. Allodynia was found in a small number of patients (11%).

CONCLUSIONS & INFERENCES

Optimal cutoff for visceral hypersensitivity was found at pressure 26 mmHg with a VAS ≥20 mm, resulting in 63.5% of IBS patients being hypersensitive and 11% being allodynic. Standardization of barostat procedures and defining optimal cutoff values for hypersensitivity is warranted when employing rectal barostat measurements for research or clinical purposes.

Therapeutic drug monitoring of thiopurine metabolites in adult thiopurine tolerant IBD patients on maintenance therapy

BACKGROUND AND AIMS

Therapeutic drug monitoring of active metabolites of thiopurines, azathioprine and 6-mercaptopurine, is relatively new. The proposed therapeutic threshold level of the active 6-thioguanine nucleotides (6-TGN) is ≥235 pmol/8×10(8) erythrocytes. The aim of this prospective cross-sectional study was to compare 6-TGN levels in adult thiopurine tolerant IBD patients with an exacerbation with those in remission, and to determine the therapeutic 6-TGN cut-off level.

METHODS

Hundred IBD patients were included. Outcome measures were thiopurine metabolite levels, calculated therapeutic 6-TGN cut-off level, CDAI/CAI scores, thiopurine dose and TPMT enzyme activity.

RESULTS

Forty-one patients had an exacerbation, 59 patients were in remission. In 17% of all patients 6-TGN levels were compatible with non-compliance. The median 6-TGN levels were not significantly different between the exacerbation and remission group (227 versus 263 pmol/8×10(8) erythrocytes, p=0.29). The previous reported therapeutic 6-TGN cut-off level of 235 pmol/8×10(8) erythrocytes was confirmed in this study. Twenty-six of the 41 patients (63%) with active disease had 6-TGN levels below this threshold and 24 of 59 IBD patients (41%) in clinical remission (p=0.04).

CONCLUSIONS

Thiopurine non-compliance occurs frequently both in active and quiescent disease. 6-TGN levels below or above the therapeutic threshold are associated with a significant higher chance of IBD exacerbation and remission, respectively. These data support the role of therapeutic drug monitoring in thiopurine maintenance therapy in IBD to reveal non-compliance or underdosing, and can be used as a practical tool to optimize thiopurine therapy, especially in case of thiopurine non-response.

Gastrointestinal symptoms in diabetes mellitus, and their relation to anxiety and depression

BACKGROUND

Prevalence of gastrointestinal (GI) symptoms is increased in patients with diabetes mellitus. In general, GI symptoms are influenced by psychological factors such as anxiety and depression, but little is known about this association in diabetic patients.

AIM

We tested the hypothesis that anxiety and depression have major impact on GI symptoms in diabetic patients.

METHODS

280 diabetic patients and 355 non-diabetic, age and sex matched controls were studied by validated questionnaires: (1) PAGI-SYM and GSRS for common GI symptoms and (2) HADS for anxiety and depression. Data were compared using logistic regression analysis.

RESULTS

Patients with diabetes scored significantly (p<0.05) higher on the symptoms diarrhea (OR 1.64, 95% CI 1.05-2.56), early satiety (OR 2.50, 95% CI 1.39-4.49) and bloating (OR 1.58, 95% CI 1.03-2.43), but not on other symptoms. Prevalence of anxiety and depression (HADS scores ≥ 8) in diabetics and controls was respectively 27.5% and 20.6% for anxiety (p<0.05), and 19.6% and 13.4% for depression (p<0.05). After adjusting for anxiety and depression only the GI symptom "early satiety" remained significantly more prevalent in the patients with diabetes.

CONCLUSIONS

The prevalence of the gastrointestinal symptoms diarrhea, bloating and early satiety, and of anxiety and depression is significantly increased in our cohort of predominantly patients with longstanding type 2 diabetes mellitus compared to controls. When adjusted for anxiety and depression, only the gastrointestinal symptom "early satiety" remained more prevalent in these diabetic patients, pointing to a somatic based origin. Thus, in our diabetic population psychological factors to a large extent are associated with gastrointestinal symptoms and should be taken into account when considering treatment of the gastrointestinal symptoms.

Validation of Ussing chamber technology to study satiety hormone release from human duodenal specimens

By developing novel screening technologies to test effects of food ingredients on hormone release, which are comparable to the in vivo situation, fewer tests may have to be performed using volunteers, whereas it still provides information that can be extrapolated to the human situation. In an in vivo intervention study, 10 lean (BMI: 20-25 kg/m(2)) and 10 obese (BMI >30 kg/m(2)) were recruited. All subjects randomly received pea protein (PP) solutions or placebo, orally and intraduodenally. Cholecystokinin (CCK) and glucagon like peptide 1 (GLP-1) release was measured over 2 h. During the oral interventions, gastrointestinal (GI) fluids were retrieved. For the present ex vivo study, duodenal biopsies were taken and placed in Ussing chambers. The luminal side was exposed to PP, placebo, intraduodenal fluid after oral PP-intake and oral placebo-intake in vivo, and a commercial pea-hydrolysate for 2 h. CCK and GLP-1 levels were measured at the serosal side. After intraduodenal PP administration in vivo, the area under the curve (AUC) for both CCK and GLP-1 was significantly increased in both lean and obese subjects. In the ex vivo study, exposure to PP resulted in significantly elevated levels of CCK and GLP-1 compared to all other test solutions. These results indicate that the ex vivo Ussing chamber technology is a valid alternative for in vivo studies, and may therefore serve as a suitable screening tool for studying the effects of nutritional compounds on the release of satiety hormones.

Nonpolypoid colorectal neoplasms: gender differences in prevalence and malignant potential

OBJECTIVE

Colonoscopy may fail to prevent colorectal cancer, especially in the proximal colon and in women. Nonpolypoid colorectal neoplasms may potentially explain some of these post-colonoscopy cancers. In the present study, we aimed to examine the prevalence and malignant potential of nonpolypoid colorectal neoplasms in a large population, with special attention to gender and location.

METHODS

We performed a cross-sectional study of all consecutive patients undergoing elective colonoscopy at a single academic medical center. The endoscopists were familiarized on the detection and treatment of nonpolypoid lesions. Advanced histology was defined by the presence of high-grade dysplasia or early cancer.

RESULTS

We included 2310 patients (53.9% women, mean age 58.4 years) with 2143 colorectal polyps. Prevalences of colorectal neoplasms and nonpolypoid colorectal neoplasms were lower in women than in men (20.9% vs. 33.7%, p < 0.001 and 3.0% vs. 5.5%, p = 0.002). In women, nonpolypoid colorectal neoplasms were significantly more likely to contain advanced histology than polypoid ones (OR 2.89, 95% CI 1.24-6.74, p = 0.01), while this was not the case in men (OR 0.91, 95% CI 0.40-2.06, p = 0.83). Proximal neoplasms with advanced histology were more likely to be nonpolypoid than distal ones (OR 4.68, 95% CI 1.54-14.2, p = 0.006).

CONCLUSION

Nonpolypoid mechanisms may play an important role in colorectal carcinogenesis, in both women and men. Although women have fewer colorectal neoplasms than men, they have nonpolypoid colorectal neoplasms, which frequently contain advanced histology.

DNA methylation of phosphatase and actin regulator 3 detects colorectal cancer in stool and complements FIT

Using a bioinformatics-based strategy, we set out to identify hypermethylated genes that could serve as biomarkers for early detection of colorectal cancer (CRC) in stool. In addition, the complementary value to a Fecal Immunochemical Test (FIT) was evaluated. Candidate genes were selected by applying cluster alignment and computational analysis of promoter regions to microarray-expression data of colorectal adenomas and carcinomas. DNA methylation was measured by quantitative methylation-specific PCR on 34 normal colon mucosa, 71 advanced adenoma, and 64 CRC tissues. The performance as biomarker was tested in whole stool samples from in total 193 subjects, including 19 with advanced adenoma and 66 with CRC. For a large proportion of these series, methylation data for GATA4 and OSMR were available for comparison. The complementary value to FIT was measured in stool subsamples from 92 subjects including 44 with advanced adenoma or CRC. Phosphatase and Actin Regulator 3 (PHACTR3) was identified as a novel hypermethylated gene showing more than 70-fold increased DNA methylation levels in advanced neoplasia compared with normal colon mucosa. In a stool training set, PHACTR3 methylation showed a sensitivity of 55% (95% CI: 33-75) for CRC and a specificity of 95% (95% CI: 87-98). In a stool validation set, sensitivity reached 66% (95% CI: 50-79) for CRC and 32% (95% CI: 14-57) for advanced adenomas at a specificity of 100% (95% CI: 86-100). Adding PHACTR3 methylation to FIT increased sensitivity for CRC up to 15%. PHACTR3 is a new hypermethylated gene in CRC with a good performance in stool DNA testing and has complementary value to FIT.

Endoscopic red flags for the detection of high-risk serrated polyps: an observational study

BACKGROUND AND STUDY AIMS

In routine practice, colonoscopy may fail to prevent colorectal cancer (CRC), especially in the proximal colon. A better endoscopic recognition of serrated polyps is important, as this pathway may explain some of the post-colonoscopy cancers. In this study, the endoscopic characteristics of serrated polyps were examined.

PATIENT AND METHODS

This was a cross-sectional, single-center study of all consecutive patients referred for elective colonoscopy during 1 year. The endoscopists were familiarized with the detection and treatment of nonpolypoid colorectal lesions. Serrated polyps were classified into high risk serrated polyps, defined as dysplastic or large (≥ 6 mm) proximal nondysplastic serrated polyps, and low risk serrated polyps including the remaining nondysplastic serrated polyps. Advanced colorectal neoplasms were defined as multiple (at least three),≥ 10 mm in size, high grade dysplastic adenomas or CRC.

RESULTS

A total of 2309 patients were included (46.1 % men, mean age 58.4 years), of whom 2.5 % (57) had at least one high risk serrated polyp and 13.9 % (322) had at least one advanced neoplasm. Overall, serrated polyps were more often nonpolypoid than adenomas (16.2 % vs. 11.1 %; P = 0.002). In total, 65 high risk serrated polyps were found, of which 43.1 % (28) displayed a nonpolypoid endoscopic appearance. Patients with advanced neoplasms were more likely to have synchronous high risk serrated polyps than patients without advanced neoplasms: OR 3.66 (95 % CI 2.03 - 6.61, P < 0.001).

CONCLUSIONS

High risk serrated polyps are frequently nonpolypoid and are associated with synchronous advanced colorectal neoplasms. Advanced colorectal neoplasms may therefore be considered red flags for the presence of high risk serrated polyps. Detection, diagnosis, and treatment of high risk serrated lesions may be important targets to improve the quality of colonoscopic cancer prevention.

Impedance measurements and high-resolution manometry help to better define rumination episodes

BACKGROUND

Rumination syndrome is a disorder of unknown etiology characterized by regurgitation of recently ingested food. We aimed to improve the diagnosis of rumination syndrome by classification of separate rumination symptoms using (1) an ambulatory manometry/impedance (AMIM) measurement and (2) a single-catheter high-resolution manometry/impedance (HRIM) measurement.

METHODS

A total of 96 symptoms during AMIM and 37 symptoms during HRIM were analyzed in five patients with clinically diagnosed rumination syndrome.

KEY RESULTS

AMIM identified rumination events in 85 out of 96 reported symptoms (symptom index (SI): 89%). Of these events, 63% were non-acidic and would have been missed by pH-metry. HRIM identified 32 out of 37 reported symptoms (SI: 86%). Upper esophageal sphincter (UES) relaxation was observed during all rumination events identified by HRIM and could be an additional criterion in the definition of rumination events.

CONCLUSIONS

Impedance measurement and high-resolution manometry contribute to a more detailed description of rumination events. Rumination events defined as gastric strain, common cavity phenomenon, retrograde esophageal fluid flow, and UES relaxation show a high SI when measured with AMIM or single-catheter HRIM.

Test performance of immunologic fecal occult blood testing and sigmoidoscopy compared with primary colonoscopy screening for colorectal advanced adenomas

Given the current increase in colorectal cancer screening, information on performance of screening tests is needed, especially in groups with a presumed lower test performance. We compared test performance of immunologic fecal occult blood testing (FIT) and pseudosigmoidoscopy with colonoscopy for detection of advanced adenomas in an average risk screening population. In addition, we explored the influence of gender, age, and location on test performance. FIT was collected prior to colonoscopy with a 50 ng/mL cutoff point. FIT results and complete colonoscopy findings were available from 329 subjects (mean age: 54.6 ± 3.7 years, 58.4% women). Advanced adenomas were detected in 38 (11.6%) of 329 subjects. Sensitivity for advanced adenomas of FIT and sigmoidoscopy were 15.8% (95% CI: 6.0-31.3) and 73.7% (95% CI: 56.9-86.6), respectively. No sensitivity improvement was obtained using the combination of sigmoidoscopy and FIT. Mean fecal hemoglobin in FIT positives was significantly lower for participants with only proximal adenomas versus those with distal ones (P = 0.008), for women versus men (P = 0.023), and for younger (<55 years) versus older (≥55 years) subjects (P = 0.029). Sensitivities of FIT were 0.0% (95% CI: 0.0-30.9) in subjects with only proximal versus 21.4% (95% CI: 8.3-41.0) in those with distal nonadvanced adenomas; 5.3% (95% CI: 0.0-26.0) in women versus 26.3% (95% CI: 9.2-51.2) in men; 9.5% (95% CI: 1.2-30.4) in younger versus 23.5% (95% CI: 6.8-49.9) in older subjects. Sigmoidoscopy had a significantly higher sensitivity for advanced adenomas than FIT. A single FIT showed very low sensitivity, especially in subjects with only proximal nonadvanced adenomas, in women, and in younger subjects. This points to the existence of "low" FIT performance in subgroups and the need for more tailored screening strategies.

Intraduodenal administration of intact pea protein effectively reduces food intake in both lean and obese male subjects

BACKGROUND

Human duodenal mucosa secretes increased levels of satiety signals upon exposure to intact protein. However, after oral protein ingestion, gastric digestion leaves little intact proteins to enter the duodenum. This study investigated whether bypassing the stomach, through intraduodenal administration, affects hormone release and food-intake to a larger extent than orally administered protein in both lean and obese subjects.

METHODS

Ten lean (BMI:23.0±0.7 kg/m²) and ten obese (BMI:33.4±1.4 kg/m²) healthy male subjects were included. All subjects randomly received either pea protein solutions (250 mg/kg bodyweight in 0.4 ml/kg bodyweight of water) or placebo (0.4 ml/kg bodyweight of water), either orally or intraduodenally via a naso-duodenal tube. Appetite-profile, plasma GLP-1, CCK, and PYY concentrations were determined over a 2 h period. After 2 h, subjects received an ad-libitum meal and food-intake was recorded.

RESULTS

CCK levels were increased at 10(p<0.02) and 20(p<0.01) minutes after intraduodenal protein administration (IPA), in obese subjects, compared to lean subjects, but also compared to oral protein administration (OPA)(p<0.04). GLP-1 levels increased after IPA in obese subjects after 90(p<0.02) to 120(p<0.01) minutes, compared to OPA. Food-intake was reduced after IPA both in lean and obese subjects (-168.9±40 kcal (p<0.01) and -298.2±44 kcal (p<0.01), respectively), compared to placebo. Also, in obese subjects, food-intake was decreased after IPA (-132.6±42 kcal; p<0.01), compared to OPA.

CONCLUSIONS

Prevention of gastric proteolysis through bypassing the stomach effectively reduces food intake, and seems to affect obese subjects to a greater extent than lean subjects. Enteric coating of intact protein supplements may provide an effective dietary strategy in the prevention/treatment of obesity.

Symptoms in patients with ulcerative colitis in remission are associated with visceral hypersensitivity and mast cell activity

OBJECTIVE

Patients with ulcerative colitis in remission (UCR) frequently report irritable bowel syndrome (IBS)-like symptoms. Recent studies have pointed to the role of mast cells in mediating visceral hypersensitivity in IBS. We hypothesized that visceral hypersensitivity is frequently present in patients with UCR and is related to the quantity and activity of mast cells in the sigmoid mucosa.

MATERIAL AND METHODS

A group of 17 controls and 19 patients with UCR were studied. Rectal compliance and perception were measured by electronic barostat. Sigmoid biopsies were taken to quantify the amount of mast cells, degranulating mast cells and mast cells in close proximity to mucosal nerve endings.

RESULTS

Visceroperception significantly increased in UCR (p < 0.05) versus controls. Rectal perception correlated positively with IBS-like symptoms in UCR (r = 0.969; p < 0.05). The amount of mucosal mast cells (per 100 crypts) was significantly increased in UCR versus controls: 228 ± 20 versus 163 ± 18 (p < 0.05). In the UCR patients a higher percentage of mucosal mast cells was in close proximity to nerve endings (58 ± 4 vs. 38 ± 3% in controls; p < 0.05) or was degranulating (40 ± 7 vs. 16 ± 4% in controls; p < 0.05). There was a significant but weak correlation between quantity of mucosal mast cells and pain perception (r = 0.32; p < 0.05).

CONCLUSION

Rectal hypersensitivity is associated with mucosal presence and activation of mast cells and with IBS-like symptoms in patients with UCR.

Leaky gut and diabetes mellitus: what is the link?

Diabetes mellitus is a chronic disease requiring lifelong medical attention. With hundreds of millions suffering worldwide, and a rapidly rising incidence, diabetes mellitus poses a great burden on healthcare systems. Recent studies investigating the underlying mechanisms involved in disease development in diabetes point to the role of the dys-regulation of the intestinal barrier. Via alterations in the intestinal permeability, intestinal barrier function becomes compromised whereby access of infectious agents and dietary antigens to mucosal immune elements is facilitated, which may eventually lead to immune reactions with damage to pancreatic beta cells and can lead to increased cytokine production with consequent insulin resistance. Understanding the factors regulating the intestinal barrier function will provide important insight into the interactions between luminal antigens and immune response elements. This review analyses recent advances in the mechanistic understanding of the role of the intestinal epithelial barrier function in the development of type 1 and type 2 diabetes. Given our current knowledge, we may assume that reinforcing the intestinal barrier can offer and open new therapeutic horizons in the treatment of type 1 and type 2 diabetes.

Review article: the clinical relevance of transient lower oesophageal sphincter relaxations in gastro-oesophageal reflux disease

BACKGROUND

Transient lower oesophageal sphincter relaxations (TLOSR) are considered the physiological mechanism that enables venting of gas from the stomach and appear as sphincter relaxations that are not induced by swallowing. It has become increasingly clear that most reflux episodes occur during TLOSRs and therefore play a key role in gastro-oesophageal reflux disease (GERD).

AIM

To describe the current knowledge about TLOSRs and its clinical implications.

METHODS

Search of the literature published in English using the PubMed database and relevant abstracts presented at international conventions.

RESULTS

Several factors influence the rate of TLOSRs including anti-reflux surgery, meal, body position, nutrition, lifestyle and a wide array of neurotransmitters. Ongoing insights in the neurotransmitters responsible for the modulation of TLOSRs, as well as the neural pathways involved in TLOSR induction, have lead to novel therapeutic targets. These therapeutic targets can serve as an add-on therapy in patients with an unsatisfactory response to proton pump inhibitor by inhibiting TLOSRs and its associated reflux events. However, the TLOSR-inhibiting drugs that are currently available still have significant side effects.

CONCLUSION

It is likely that in the future, selected GERD patients may benefit from transient lower oesophageal sphincter relaxation inhibition when compounds are found without significant side effects.

Proton pump inhibitor use is associated with an increased risk for microscopic colitis: a case-control study

BACKGROUND

Microscopic colitis causes chronic watery diarrhoea. Recent studies have suggested an aetiological role for various medications, including proton pump inhibitors, in the pathogenesis of microscopic colitis.

AIM

To determine whether an association exists between microscopic colitis and proton pump inhibitor use in patients with documented microscopic colitis vs. age- and gender-matched controls.

METHODS

In this retrospective case-control study, cases of microscopic colitis from a secondary and tertiary referral medical centre diagnosed in the last 5 years were reviewed. Demographic characteristics, clinical, histological and endoscopic records, as well as exposure to PPIs and NSAIDs were assessed. Controls from the population were matched to cases by gender and by age.

RESULTS

During the investigated period, 136 cases were identified in both hospitals. Of these, 95 cases of microscopic colitis were retrieved for detailed analysis. Exposure to proton pump inhibitors at the time of the histological diagnosis was significantly higher in patients with collagenous colitis than in controls [38% vs. 13%, P < 0.001; adjusted OR of 4.5 (95% CI 2.0-9.5)].

CONCLUSIONS

This observation confirms the presumed association between microscopic colitis and PPI use, and it supports the possible aetiological role of PPI exposure in the development of microscopic colitis.

Development of expertise in the detection and classification of non-polypoid colorectal neoplasia: Experience-based data at an academic GI unit

At its core, quality improvement in gastrointestinal (GI) practice relies on continuous training, education, and information among all health care providers, whether gastroenterologists, GI trainees, endoscopy nurses, or GI pathologists. Over the past few years, it became clear that objective criteria are needed to assess the quality of colonoscopy, such as cecum intubation rate, quality of bowel preparation, withdrawal time, and adenoma detection rate. In this context, development of competence among practicing endoscopists to adequately detect and treat non-polypoid colorectal neoplasms (NP-CRNs) deserves special attention. We describe a summary of the path to develop expertise in detection and management of NP-CRNs, based on experience at our academic GI unit.

Understanding the role of tryptophan and serotonin metabolism in gastrointestinal function

Tryptophan is the precursor of a wide array of metabolites, which are involved in a variety of aspects of human nutrition and metabolism. Accumulating evidence suggests a role of tryptophan metabolites, especially serotonin (5-hydroxytryptamin) in intestinal (patho) physiology, although mechanisms of action are still poorly understood. Alterations of serotonin metabolism may give rise to gastrointestinal dysfunction. Recently, it has been postulated that other metabolites of tryptophan, mostly of the kynurenine pathway, also play a role in regulating gut function. This review analyses the current knowledge of the interrelationship between tryptophan metabolic pathways and summarizes the existing scientific evidence regarding the role of tryptophan metabolites in intestinal function and in the pathogenesis of gastrointestinal diseases.

Effect of fat saturation on satiety, hormone release, and food intake

BACKGROUND

Ileal delivery of fat reduces hunger and food intake through activation of the ileal brake. Physicochemical properties of fat have been shown to affect satiety and food intake.

OBJECTIVE

The objective of this study was to assess the effect of ileal fat emulsions with differing degrees of fatty acid saturation on satiety, food intake, and gut peptides (cholecystokinin and peptide YY). We hypothesized that long-chain triacylglycerols with diunsaturated fatty acids would increase satiety and reduce energy intake compared with long-chain triacylglycerols with monounsaturated or saturated fatty acids.

DESIGN

We performed a double-blind, randomized, crossover study in which 15 healthy subjects [mean age: 24 y; mean body mass index (in kg/m(2)): 22] were intubated with a naso-ileal catheter and participated in 4 experiments performed in random order on 4 consecutive days. After consumption of a liquid meal, subjects received a fat or control infusion in the ileum. Fat emulsions consisted of 6 g of 18:0 (shea oil; mainly 18:0), 18:1 (canola oil; mainly 18:1), or 18:2 (safflower oil; mainly 18:2) oils. Food intake was measured during an ad libitum lunch. Satiety questionnaires (visual analog scale) and blood samples were collected at regular intervals.

RESULTS

Compared with the control, only 18:2 and 18:1 significantly increased fullness and reduced hunger. No effect on food intake was observed. 18:1 and 18:2 increased cholecystokinin secretion significantly compared with the control. Fatty acid saturation did not affect peptide YY secretion.

CONCLUSIONS

When infused into the ileum, triacylglycerols with unsaturated fatty acids increase satiety, whereas triacylglycerols with saturated fatty acids does not. This trial was registered with the Dutch Trial Register as: ISRCTN51742545.

Ileal brake: a sensible food target for appetite control. A review

With the rising prevalence of obesity and related health problems increases, there is increased interest in the gastrointestinal system as a possible target for pharmacological or food-based approaches to weight management. Recent studies have shown that under normal physiological situations undigested nutrients can reach the ileum, and induce activation of the so-called "ileal brake", a combination of effects influencing digestive process and ingestive behaviour. The relevance of the ileal brake as a potential target for weight management is based on several findings: First, activation of the ileal brake has been shown to reduce food intake and increase satiety levels. Second, surgical procedures that increase exposure of the ileum to nutrients produce weight loss and improved glycaemic control. Third, the appetite-reducing effect of chronic ileal brake activation appears to be maintained over time. Together, this evidence suggests that activation of the ileal brake is an excellent long-term target to achieve sustainable reductions in food intake. This review addresses the role of the ileal brake in gut function, and considers the possible involvement of several peptide hormone mediators. Attention is given to the ability of macronutrients to activate the ileal brake, and particularly variation attributable to the physicochemical properties of fats. The emphasis is on implications of ileal brake stimulation on food intake and satiety, accompanied by evidence of effects on glycaemic control and weight loss.

Gallstone formation after pancreas and/or kidney transplantation: an analysis of risk factors

Pancreas and kidney transplantation (SPK) is the treatment of choice for patients with type 1 diabetes mellitus and end-stage renal failure. Gallstones are common after SPK transplantation but little is known about the true incidence and etiology of gallstones in this group. We therefore evaluated the incidence of gallstones and the presence of transplant-related risk factors in patients after SPK and kidney transplantation alone (KTA). Data were evaluated of 56 consecutive patients who underwent SPK transplantation and compared the results with those of 91 consecutive nondiabetic patients who underwent KTA transplantation at the Leiden University Medical Center between 1987 and 1994. Of the 58 evaluable KTA patients, 20.7% developed gallstones during 7.7 yr of follow-up and in the SPK group 43.9% of the 41 evaluable patients developed gallstones during 7.1 yr of follow-up. Postoperative weight loss and cyclosporin A-related hepatotoxicity correlated with gallstone formation both in SPK and KTA patients. In addition, the duration of postoperative fasting and autonomic neuropathy correlated with gallstones in SPK patients. It is concluded that both in patients after SPK transplantation and in patients after KTA transplantation, the risk to develop gallstones is significantly increased. Physicians should be aware of the high incidence of gallstones in SPK recipients.

Review article: The diagnosis and management of gastroparesis

BACKGROUND

Gastroparesis is a disorder characterized by a delay in gastric emptying of a meal in the absence of a mechanical gastric outlet obstruction.

AIM

To provide an evidence based overview on diagnosis and management of gastroparesis.

METHODS

A PubMed search was performed using search terms including gastroparesis, gastric retention, gastric emptying, accommodation, manometry, prokinetics, antiemetics, metoclopramide, domperidone, erythromycin, botulinum toxin, gastric pacing. Relevant studies were identified and original articles and reviews were collected. References in these articles were examined for relevance and included where appropriate.

RESULTS

Diagnosis of gastroparesis is based on the presence of symptoms such as nausea, vomiting and postprandial abdominal fullness and on an objectively determined delay in gastric emptying. The true prevalence of gastroparesis is unknown. Gastric emptying can be assessed by scintigraphy and stable isotope breath tests. Management of gastroparesis consists of dietary and lifestyle measures and/or pharmacological interventions (prokinetics, antiemetics, intrapyloric botulinum toxin injection) or other interventions that focus on adequate nutrient intake either through a nasoduodenal tube, percutaneous gastrostomy or jejunostomy.

CONCLUSIONS

Accurate diagnosis of gastroparesis requires an adequate protocol to measure gastric emptying. Treatment options in gastroparesis remain limited despite the disabling nature of the disorder.

Clinical trial: short- and long-term benefit of relaxation training for irritable bowel syndrome

BACKGROUND

Psychotherapy is effective in treating irritable bowel syndrome, but the effect of relaxation training, a brief psychological group intervention, is not known.

AIM

To determine the efficacy of relaxation training in a large cohort of irritable bowel syndrome patients.

METHODS

Ninety-eight irritable bowel syndrome patients were included in this randomized controlled trial. Forty-six patients received standard medical care (CON) and 52 received four 90-min sessions of relaxation training in small groups in addition to standard medical care. Irritable bowel syndrome symptom severity, medical consumption and quality of life were assessed at baseline in patients and in 38 healthy controls and evaluated in patients at 3, 6 and 12 months after intervention.

RESULTS

Irritable bowel syndrome symptom severity was significantly reduced in the relaxation training group compared to CON at 3, 6 and 12 months after treatment (time-by-treatment interaction, P = 0.002). The number needed to treat for long-term improvement was 5. Quality of life had improved (general health, P = 0.017; health change, P = 0.05). Frequency of doctor visits was reduced (P = 0.039).

CONCLUSIONS

Relaxation training is a brief group intervention that significantly improves symptom severity, general health perception and medical consumption in irritable bowel syndrome patients immediately after, as well as 6 and 12 months after intervention.

Recto-colonic reflex is impaired in patients with irritable bowel syndrome

Motor and sensory dysfunction of the gut are present in a subset of patients with irritable bowel syndrome (IBS). Recent studies have demonstrated the presence of a recto-colonic inhibitory reflex in healthy humans. It is not known whether this reflex exists in IBS. We studied rectal compliance, perception and the recto-colonic reflex by measuring volume responses of the descending colon to rectal distentions by barostat in 26 IBS patients and 13 healthy controls under both fasting and postprandial conditions. In the fasting state, rectal distention inhibited colonic tone and phasic motility to a similar extent in health and IBS. After a meal, rectal distention inhibited colonic tone and phasic motility to a lesser degree (P < 0.05) in IBS than health. Under postprandial but not fasting conditions, rectal distentions of increasing intensity were associated with higher pain scores in IBS than in health. Rectal distention inhibits tonic and phasic motility of the descending colon in healthy controls and in IBS patients. Postprandially this recto-colonic inhibitory reflex is impaired and attenuated in IBS patients compared with controls. These findings point to an altered reflex function in IBS and have implications for pathophysiology and therapy.

The effect of laparoscopic partial fundoplication on dysphagia, esophageal and lower esophageal sphincter motility

It has been suggested that dysphagia is less common after partial versus complete fundoplication. The mechanisms contributing to postoperative dysphagia remain unclear. The objective of the present prospective study was to investigate esophageal motility and the prevalence of dysphagia in patients who have undergone laparoscopic partial fundoplication. Symptoms, lower esophageal sphincter (LES) characteristics and esophageal body motility were evaluated prospectively in 62 patients before and after laparoscopic partial fundoplication: 33 women and 29 men with a mean age of 44 +/- 1.5 years (range, 21-71). The patients filled in symptom questionnaires and underwent stationary and ambulatory manometry and 24-h pH-metry before and after operation. A small but significant increase in LES pressure from 14.8 +/- 0.9 to 17.8 +/- 0.8 mmHg was seen after laparoscopic partial fundoplication. Further, LES characteristics and esophageal body motility were not different post- versus preoperation. Three months after surgery, dysphagia was present in eight patients. No differences in LES characteristics or body motility were present between patients with and without dysphagia. Six months after the operation dysphagia was present in only three patients (3.2% mild and 1.6% severe dysphagia). Adequate reflux control was obtained in 85% of the patients. Laparoscopic partial fundoplication offers adequate reflux control without affecting esophageal body motility and with a very low incidence of postoperative dysphagia.

Effect of fat digestion on superior mesenteric artery blood flow in humans

BACKGROUND AND AIM

Intraluminal nutrients stimulate superior mesenteric artery (SMA) blood flow. Of the macronutrients, especially fat affects the magnitude of the SMA blood flow response to a meal. Little is known however on the influence of fat hydrolysis on SMA flow.

METHODS

We compared in eight healthy volunteers the SMA flow response (Doppler ultrasonography) to continuous intraduodenal fat perfusion (LCT, 240 kCal h(-1)) during conditions with normal hydrolysis (placebo, control), increased hydrolysis (pancreatic enzyme supplementation; 50 kU lipase) and impaired hydrolysis (orlistat 240 mg).

RESULTS

Intraduodenal LCT significantly (P<0.01) increased SMA flow in all experiments over basal. The SMA flow response to fat during pancreatic enzyme supplementation (1.49 +/- 0.1 l min(-1)) was significantly (P<0.05) higher compared with placebo (1.11 +/- 0.16 l min(-1)). Lipase inhibition with orlistat did not significantly affect fat stimulated SMA flow compared with placebo: 0.89 +/- 0.08 l min(-1) versus 1.11 +/- 0.16 l min(-1).

CONCLUSIONS

Administration of pancreatic enzymes significantly increases fat stimulated SMA flow. Fat digest products in the intestinal lumen contribute to the regulation of SMA blood flow.

Gastric accommodation and motility are influenced by the barostat device: Assessment with magnetic resonance imaging

The barostat is considered the gold standard for evaluation of proximal gastric motility especially for the accommodation response to a meal. The procedure is invasive because it involves the introduction of an intragastric catheter and bag and is not always well tolerated. Moreover, the barostat bag itself may influence motility. Nowadays magnetic resonance imaging (MRI) is able to measure several aspects of gastric motility noninvasively. To evaluate whether the accommodation response of the stomach, observed with the barostat, is present during MRI and whether the barostat interferes with gastric physiology, gastric accommodation, motility, and emptying were studied twice in 14 healthy subjects with MRI using three-dimensional volume scans and two-dimensional dynamic scans once in the presence of a barostat bag and once when the barostat bag was not present. Fasting and postprandial intragastric volumes were significantly higher in the experiment with barostat vs. without barostat (fasting: 350 +/- 132 ml vs. 37 +/- 21 ml, P < 0.0001; postprandial: 852 +/- 126 ml vs. 361 +/- 62 ml, P < 0.0001). No significant differences were found in gastric emptying (88 +/- 41 vs. 97 +/- 40 ml/h, not significant) and contraction frequency between both experiments. The accommodation response observed in the presence of the barostat bag was not observed in the absence of the barostat bag. In conclusion, the presence of an intragastric barostat bag does not interfere with gastric emptying or motility, but the accommodation response measured with the barostat in situ is not observed without the barostat bag in situ. Gastric accommodation is a nonphysiological barostat-induced phenomenon.

Octreotide therapy in dumping syndrome: Analysis of long-term results

BACKGROUND

Octreotide therapy is effective in controlling severe dumping symptoms during short-term follow-up but little is known about long-term results.

AIM

To report on the long-term results of patients with severe dumping syndrome treated at the Leiden University Medical Center with subcutaneous or depot intramuscular (long-acting release) octreotide.

METHODS

Follow-up of 34 patients with severe dumping syndrome refractory to other therapeutic measures treated between 1987 and 2005 with octreotide subcutaneous/long-acting release. At regular intervals symptoms, quality of life, weight, faecal fat excretion and gallstone formation were evaluated.

RESULTS

All patients had excellent initial relief of symptoms during octreotide subcutaneous therapy. However, during follow-up 16 patients stopped therapy because of side effects (n = 9) or loss of efficacy (n = 7). Four patients died. Fourteen patients (41%) remain using octreotide (follow-up 93 +/- 15 months), seven are on octreotide subcutaneous and seven on octreotide long-acting release. Patients with severe dumping (both early and late) do better on subcutaneous than long-acting release despite the inconvenience of frequent injections. Dumping symptoms are reduced by 50% even in long-term users. Body weight continues to increase during therapy despite more pronounced steatorrhoea.

CONCLUSION

The long-term the efficacy of octreotide is much less favourable compared with short-term treatment.

The outcome of a long-term follow-up of pancreatic function after recovery from acute pancreatitis

CONTEXT

It is generally assumed that pancreatic function recovers completely after mild but not after severe acute pancreatitis.

OBJECTIVE

To evaluate both pancreatic function and quality of life in patients who had recovered from acute pancreatitis in a long-term follow-up study.

PARTICIPANTS

Thirty-four patients (mean age: 56 years) who had recovered from biliary (n=26) or post ERCP (n=8) acute pancreatitis. The mean time after the event was 4.6 years.

MAIN OUTCOME MEASURES

Pancreatic function was evaluated by fecal fat excretion, urinary 4-aminobenzoic acid (PABA) recovery, oral glucose tolerance test and pancreatic polypeptide (PP) secretion. In addition, the quality of life was measured by the gastrointestinal quality of life index (GIQLI).

RESULTS

Of the 34 patients, 22 (65%) had mild and 12 (35%) had severe acute pancreatitis. Exocrine insufficiency (fecal fat greater than 7 g/24h and/or urinary PABA recovery less than 50%) was present in 22 (65%) patients: in 10 (83%) after severe and in 12 (55%) after mild acute pancreatitis, respectively (P=0.140). Endocrine insufficiency was present in 12 patients (35%): 7 (32%) mild versus 5 (42%) severe acute pancreatitis; P=0.711. the quality of life was significantly impaired after acute pancreatitis, (P=0.024). No significant relationship was found between the severity of the pancreatitis and impairment of the quality of life (P=0.604).

CONCLUSION

In a significant proportion of patients who had recovered from acute pancreatitis, exocrine and endocrine functional impairment was found. This finding is not confined only to patients after severe acute pancreatitis. Routine evaluation of pancreatic function after acute pancreatitis should be considered.

Efficacy of lower than standard doses of pancreatic enzyme supplementation therapy during acid inhibition in patients with pancreatic exocrine insufficiency

GOAL

To compare, during strong acid inhibition with omeprazole, the effect of 2 different doses of an enteric-coated pancreatic enzyme preparation on fecal fat excretion and abdominal symptoms in patients with exocrine insufficiency due to chronic pancreatitis (CP).

BACKGROUND

Treatment with pancreatic enzymes reduces fecal fat excretion in patients with CP but is rather unsuccessful due to irreversible lipase inactivation at pH below 4.

STUDY

Sixteen patients with CP (3 women, 13 men; age 53+/-3 y) participated in this randomized double blind 2-way cross over study. Fecal fat excretion and fat intake were measured and abdominal symptoms (visual analog scales) were scored during a 2 weeks control period, during omeprazole 60 mg+pancreatic enzymes 10,000 Fédération Internationale Pharmaceutique IU lipase tid (treatment A) for 2 weeks and during omeprazole 60 mg+pancreatic enzymes, 20,000 Fédération Internationale Pharmaceutique IU lipase tid (treatment B) for 2 weeks.

RESULTS

During acid inhibition with enzyme supplementation fecal fat excretion was significantly (P<0.01) reduced compared with control: 18+/-7 and 18+/-5 g/24 h versus 36+/-8 g/24 h for treatment A, B, and control, respectively. Abdominal symptom score and general well being improved significantly (P<0.05) during treatments A and B versus control. No differences in fat excretion or symptoms scores between treatments A and B were observed.

CONCLUSIONS

During strong acid inhibition, lower than recommended oral doses of pancreatic enzymes are therapeutically effective with respect to fat absorption and symptom reduction.

Intragastric acidification inhibits motilin-induced phase III activity in humans

In a randomized, placebo-controlled crossover design we studied the effect of gastric acidification on motilin-induced interdigestive antropyloroduodenal motility. Ten healthy volunteers participated in the study consisting of four experiments. Each experiment started after a spontaneous occurring phase III and consisted of intragastric infusion of either saline or acid (0.08 mol L(-1) HCl) for 90 min and intravenous infusion of either saline or motilin (4 pmol kg(-1) min(-1)) for 30 min. Antropyloroduodenal motility and pH were recorded continuously for 240 min. Reoccurrence of phase III was significantly (P < 0.05) earlier during intragastric saline-intravenous motilin infusion compared with control (intragastric saline-intravenous saline), 52 min (range 25-79) and 113 min (84-141) respectively. This effect was completely abolished during intragastric acid-intravenous motilin infusion, 112 min (82-142). The percentage of phase III of antral origin was significantly (P < 0.05) higher during intragastric saline-intravenous motilin infusion (90%) compared with control (30%). The mean area under the contraction (AUC) for phase II was significantly (P < 0.05) lower during intragastric saline-intravenous motilin infusion and intragastric acid-intravenous saline infusion compared with control. It is concluded that in humans intragastric acidification inhibits the effect of motilin on antroduodenal motility, decreases the AUC of antral phase II contractions and delays the occurrence of phase III of the migrating motor complex.

Fish oil increases bile acid synthesis in male patients with hypertriglyceridemia

Fibrates are drugs of choice in patients with hypertriglyceridemia (HTG), but may increase the risk for gallstones by decreasing bile acid synthesis. Fish oil might be a therapeutic alternative, but its effect on bile acid metabolism in humans is unknown. We compared the effects of triglyceride-lowering therapy by fish oil or bezafibrate on cholesterol synthesis and bile acid metabolism in HTG. Cholesterol synthesis, bile acid pool sizes, and synthesis rates were compared between 9 male HTG patients and 10 normolipidemic controls matched for age, sex, and BMI. Effects of bezafibrate or fish oil were studied only in HTG patients in a randomized crossover trial. Patients had 14-fold higher serum triglyceride concentrations and greater cholesterol synthesis, as indicated by a 107% higher ratio of serum lathosterol to cholesterol (P < 0.01) than controls. The groups did not differ in bile acid metabolism. Both bezafibrate and fish oil reduced serum TG concentration (-68 and -51% vs. baseline, respectively). Compared with baseline, bezafibrate therapy was associated with reduced cholesterol synthesis (-25%, P = 0.009) without changes in bile acid synthesis rate and pool size. In contrast, fish oil increased bile acid synthesis (+31% vs. baseline, P = 0.07 and +53% vs. bezafibrate, P = 0.02) and altered bile acid distribution, as reflected by an increased ratio of the cholic acid (CA) synthesis rate to the chenodeoxycholic acid (CDCA) synthesis rate (+35% vs baseline, P = 0.05 and + 32% vs bezafibrate, P = 0.07) without effects on bile acid pool size or cholesterol synthesis. In conclusion, cholesterol synthesis is greater in HTG patients than in controls, whereas bile acid synthesis does not differ. Bezafibrate and fish oil have similar triglyceride-lowering capacities, but distinct effects on cholesterol synthesis. Bile acid synthesis is increased by fish oil, but not by bezafibrate therapy.

Proximal and distal gut hormone secretion in irritable bowel syndrome

OBJECTIVE

Sensory and motor dysfunctions of the gut are both important characteristics of irritable bowel syndrome (IBS). Several gut peptides contribute to the regulation of gastrointestinal function but little is known about gut hormone secretion in IBS.

MATERIAL AND METHODS

We evaluated perceptual thresholds and fasting and postprandial plasma levels of proximal (cholecystokinin (CCK), motilin) and distal (peptide YY) gut peptides up to 1 h after ingestion of a high caloric meal in 99 IBS patients and 40 age- and gender-matched healthy controls.

RESULTS

Fasting plasma CCK levels were significantly elevated in patients (1.2+/-0.8 pM) compared with those in controls (0.8+/-0.7 pM, p=0.006), as was the incremental postprandial CCK response (72+/-73 versus 40+/-42 pM.60 min, respectively; p=0.003). No differences in fasting and postprandial motilin or PYY levels were found. The postprandial PYY response was significantly increased in hypersensitive compared to normosensitive patients (215+/-135 versus 162+/-169 pM, p=0.048). Patients with a diarrhoea predominant bowel habit had higher fasting motilin levels compared to constipated patients or alternating type IBS patients (82.1+/-36.5 versus 60.8+/-25.1 versus 57.5+/-23.9 pM, one-way ANOVA p=0.003).

CONCLUSIONS

IBS patients have increased fasting and postprandial plasma levels of CCK. Changes in plasma levels of motilin and PYY may contribute to the clinical expression of IBS, such as the presence of visceral hypersensitivity or a predominant bowel habit.

Risk factors of frequent exacerbations in difficult-to-treat asthma

Recurrent exacerbations are a major cause of morbidity and medical expenditure in patients with asthma. Various exogenous and endogenous factors are thought to influence the level of asthma control, but systematical data on the involvement of these factors in the recurrence of asthma exacerbations are scarce. In this study, 13 clinical and environmental factors potentially associated with recurrent exacerbations were investigated in 136 patients with difficult-to-treat asthma. Patients with more than three severe exacerbations (n = 39) in the previous year were compared with those with only one exacerbation per year (n = 24). A systematic diagnostic protocol was used to assess 13 potential risk factors. Factors significantly associated with frequent exacerbations included: severe nasal sinus disease (adjusted odds ratio (OR) 3.7); gastro-oesophageal reflux (OR 4.9); recurrent respiratory infections (OR 6.9); psychological dysfunctioning (OR 10.8); and obstructive sleep apnoea (OR 3.4). Severe chronic sinus disease and psychological dysfunctioning were the only independently associated factors (adjusted OR 5.5 and 11.7, respectively). All patients with frequent exacerbations exhibited at least one of these five factors, whilst 52% showed three or more factors. In conclusion, the results show that recurrent exacerbations in asthma are associated with specific co-morbid factors that are easy to detect and that are treatable. Therapeutic interventions aimed at correcting these factors are likely to reduce morbidity and medical expenditure in these patients.

Efficacy of depot long-acting release octreotide therapy in severe dumping syndrome

BACKGROUND

Dumping syndrome is a serious complication occurring in 10% of patients after gastric surgery. Dumping symptoms are effectively reduced by subcutaneous application of the somatostatin analogue octreotide, but side-effects limit its use.

AIM

To evaluate the efficacy of depot long-acting release octreotide (Sandostatin-LAR) vs. octreotide subcutaneous on dumping symptoms, quality of life and side-effects.

METHODS

Twelve patients (five females, age 58 +/- 3 years) with severe dumping symptoms, requiring daily use of octreotide subcutaneous, were included in an open study and changed from octreotide subcutaneous after a 2 weeks washout to Sandostatin-LAR 10 mg i.m., every 4 weeks for 6 months. Symptoms (diary), body weight, fat excretion, food intake and Gastrointestinal Specific Quality of Life Index were evaluated.

RESULTS

Gastrointestinal Specific Quality of Life Index increased significantly (P < 0.05) during Sandostatin-LAR treatment (88 +/- 4) compared with octreotide (74 +/- 4) and washout (75 +/- 6). During Sandostatin-LAR treatment, abdominal symptom score was lower compared with octreotide and washout, but not significantly. During Sandostatin-LAR treatment, body weight increased (66 +/- 4 to 70 +/- 3 kg; P = 0.19).

CONCLUSIONS

Sandostatin-LAR is at least as effective as octreotide subcutaneous in suppressing symptoms in patients with severe dumping syndrome and is more effective than octreotide subcutaneous in increasing body weight and quality of life.

Role of tumor necrosis factor-alpha and interleukin-10 gene polymorphisms in irritable bowel syndrome

OBJECTIVES

Imbalances in the genetically controlled pro- and anti-inflammatory cytokine production may promote ongoing low-grade inflammation after an acute gastroenteritis, and subsequently, irritable bowel syndrome (IBS) (post-infectious IBS, PI-IBS). We studied gene promoter single nucleotide polymorphisms (SNPs) of tumor necrosis factor-alpha (TNF-alpha, pro-inflammatory) and interleukin-10 (IL-10, anti-inflammatory) in IBS patients and controls.

METHODS

DNA was extracted from peripheral blood leucocytes of 111 IBS patients and 162 healthy controls. Genotype and allele frequencies were assessed by analyzing SNPs at position -308 (TNF-alpha) and -1082 and -819 (IL-10).

RESULTS

Homozygous high producers for TNF-alpha (A/A) were rare (overall prevalence 2.6%). The heterozygous TNF-alpha genotype (G/A, high producer) was significantly more prevalent in IBS compared to controls (41%vs 26%, p= 0.02). More patients (41%) than controls (30%) were positive for the A allele (p= 0.044; odds ratio (OR) 1.68, 95% confidence interval (CI) 1.01-2.79), with a similar trend for diarrhea (54%) versus constipation and alternating subtypes (<33%, p= 0.079), but not for subgroups according to a history of acute gastroenteritis. IL-10 genotypes were similarly distributed in patients and controls for both SNPs. Possession of a high producer TNF-alpha and a low producer IL-10 genotype were significantly more prevalent in IBS (9%) versus controls (3%, p= 0.035; OR 3.11, 95% CI 1.03-9.36) and in diarrhea (20%) compared to other IBS subtypes (<4%, p= 0.026).

CONCLUSIONS

Our results support the emerging hypothesis that genetically determined immune activity plays a role in the pathophysiology of IBS. Future studies in larger, clinically relevant, IBS subgroups are warranted to establish definite associations with cytokine gene polymorphisms.

Viscerosensory-cardiovascular reflexes: altered baroreflex sensitivity in irritable bowel syndrome

Animal studies have demonstrated that visceral afferent stimulation alters autonomic cardiovascular reflexes. This mechanism might play an important role in the pathophysiology of conditions associated with visceral hypersensitivity, such as irritable bowel syndrome (IBS). As such, studies in humans are lacking, we measured viscerosensory-cardiovascular reflex interactions in IBS patients and healthy controls. Systolic blood pressure (SBP), heart rate (HR), and arterial baroreflex sensitivity (BRS) were studied in 87 IBS patients and 36 healthy controls under baseline conditions and during mild (15 mmHg) and intense (35 mmHg) visceral stimulation by rectal balloon distension. BRS was computed from continuous ECG and arterial blood pressure signals (Finapres-method) during 5-min periods of 15-min metronome respiration. Baseline SBP and HR were not different between patients and controls. In both groups, SBP increased similarly during rectal stimulation, whereas HR decreased during mild and increased intense stimulation. BRS was significantly higher in patients compared with controls at baseline (7.9 +/- 5.4 vs. 5.7 +/- 3.7 ms/mmHg, P = 0.03) and increased significantly in both groups during mild stimulation. This increase persisted in controls during intense stimulation, but BRS returned to baseline in patients. BRS was not significantly different between groups during rectal distension. This study demonstrates the presence of a viscerosensory-cardiovascular reflex in healthy individuals and in IBS patients. The increased BRS in IBS patients at baseline may either be a training-effect (frequent challenging of the reflex) or reflects altered viscerosensory processing at the nucleus tractus solitarii.

Gastric emptying and vagus nerve function after laparoscopic partial fundoplication

OBJECTIVE

To establish the relation between vagus nerve dysfunction, gastric emptying, and antireflux surgery.

SUMMARY BACKGROUND DATA

Delayed gastric emptying occurs in up to 40% of reflux patients. After antireflux surgery, gastric emptying becomes normal or is even accelerated. Occasionally, severe gastric stasis is found and is associated with a negative outcome of the antireflux procedure. It has been suggested that injury to the vagus nerve could be the cause of this delayed emptying.

METHODS

We evaluated in a prospective study gastric emptying of solids and vagus nerve function (pancreatic polypeptide response to hypoglycemia) before and after surgery in 41 patients (22 women; age 43 +/- 1.6 years) who underwent laparoscopic hemifundoplication.

RESULTS

All patients had relief of reflux symptoms varying from adequate (n = 8) to complete relief (n = 33). Gastric emptying of solids increased significantly (P < 0.001) after operation: lag phase from 19 +/- 2 to 10 +/- 1 minute, emptying rate (%/h) from 37 +/- 2 to 48 +/- 5 and half emptying time from 110 +/- 8 to 81 +/- 4 minutes. Gastric emptying improved to a similar extent in patients with delayed and normal preoperative gastric emptying. Postoperative signs of vagus nerve damage (PP peak < 47pmol/L) were present in 4 patients (10%). In these 4 patients gastric emptying both before and after operation did not differ from patients with normal vagus nerve function. In fact, none of the 41 patients had severely delayed emptying after laparoscopic hemifundoplication.

CONCLUSIONS

Laparoscopic hemifundoplication affects vagus nerve integrity in 10% of patients, but this does not lead to a delay in gastric emptying. In fact, gastric emptying improved significantly after fundoplication.

Effects of a nonpeptide motilin receptor antagonist on proximal gastric motor function

AIM

To assess the effects of the motilin receptor antagonist RWJ-68023 on basal and motilin-stimulated proximal gastric volume.

METHODS

Eighteen healthy male volunteers received RWJ-68023 in two different doses or placebo for 135 min. After 45 min, subjects received a motilin infusion for 90 min. Proximal gastric volume was measured with a barostat at constant pressure and during isobaric distensions. Abdominal symptoms were scored using visual analogue scales. Motilin and RWJ-68023 concentrations were assessed by radioimmunoassay and liquid chromatography-mass spectrometry, respectively.

RESULTS

Both dosages of RWJ-68023 were safe and well tolerated. The most common adverse events were of gastrointestinal origin. RWJ-68023 did not affect basal proximal gastric volume, but the high-dose RWJ-68023 reduced the contractile effect of motilin on the stomach. This antagonizing effect of RWJ-68023 was only significant (P = 0.014) during the distension procedure.

CONCLUSIONS

The RWJ-68023 doses used in this study were selected to accomplish plasma concentrations that would block the motilin effect entirely. However, the antagonizing effect of RWJ-68023 was partial and only present when the tonic condition of the stomach was modulated by motilin.

Comparison of two techniques for lower oesophageal sphincter manometry: sleeve and sphinctometer

We have compared the sphinctometer with the water-perfused sleeve (gold standard) for measurement of lower oesophageal sphincter (LOS) characteristics by simultaneous recording. LOS pressure and transient LOS relaxations (TLOSR) measured by sleeve and sphinctometer in 11 healthy volunteers showed identical patterns. However, output of the sphinctometer was significantly (P < 0.01) lower than output of the sleeve. A total of 249 TLOSR were recorded. Of these, 176 TLOSR were identified by both sleeve and sphinctometer, 50 TLOSR were identified by sleeve alone and 23 TLOSR by sphinctometer alone. Due to the lower pressure output of the sphinctometer, 29 LOS relaxations did not reach criteria to qualify as TLOSRs. When TLOSR criteria were adjusted for sphinctometer pressure measurements, the number of TLOSRs identified by both sleeve and sphinctometer increased from 176 to 205. In conclusion, in healthy volunteers the sphinctometer registers TLOSR with results comparable with sleeve recording. However at low LOS pressures, the number of TLOSR is underscored by the sphinctometer.

Gallbladder volume as a biomarker for the motilin effect in healthy volunteers and patients with functional dyspepsia

AIM

To investigate a motilin effect on gallbladder volume in healthy volunteers and patients with functional dyspepsia.

METHODS

Forty-three healthy volunteers and 10 patients with functional dyspepsia received motilin (4 pmol.min/kg) or placebo in four separate double-blind, randomized, placebo-controlled, cross-over studies. The gallbladder volume was measured by ultrasonography. Analysis of variance of the combined data of these studies was performed to investigate a motilin effect on gallbladder volume and potential differences between patients and healthy volunteers.

RESULTS

The baseline gallbladder volume was similar for placebo and motilin treatment, as well as for patients and healthy volunteers. Motilin, compared with placebo, significantly decreased the gallbladder volume in healthy volunteers (P = 0.003) and patients (P < 0.0001). A linear concentration-response relationship was observed. The decrease in gallbladder volume by motilin was greater in patients (P = 0.03). The motilin effect was consistent between studies.

CONCLUSION

The interdigestive gallbladder volume is a non-invasive end-point for motilin activity, displaying a consistent response across studies, a clear response to motilin and a clear concentration-response relationship. However, it is less suitable as a biomarker for future pharmacological studies on motilin agonists or antagonists as the effect is probably indirect, and a relatively large study population of 27 subjects is required to demonstrate a 15% decrease in gallbladder volume. Further investigation is required to confirm altered gallbladder motility as a feature of functional dyspepsia.

Effect of surgery for chronic pancreatitis on pancreatic function: pancreatico-jejunostomy and duodenum-preserving resection of the head of the pancreas

BACKGROUND

Resection and drainage procedures are performed for chronic pancreatitis. After resection, pancreatic function deteriorates; however, little is known about the effect of drainage procedures.

METHODS

Pancreatic function was evaluated prospectively before and after surgery in 27 patients with duodenum-preserving resection of the head of the pancreas (DPRHP), and in 12 patients with pancreatico-jejunostomy (P-JS); 18 patients with chronic pancreatitis served as controls. Results of the 2 groups were not compared because of differences in patient characteristics and indications for surgery. Endpoints were exocrine function (fecal fat excretion, urinary PABA recovery), endocrine function (oral glucose tolerance test, serum C-peptide concentrations), and pancreatic polypeptide secretion.

RESULTS

Groups were not different with respect to age and duration of symptoms. Median urinary PABA recovery was not altered significantly after surgery: DPRHP, from 40% to 31%; P-JS, from 52% to 44%; and controls, from 43% to 48%. Median fecal fat also did not change significantly: DPRHP, from 6 to 12 g/24 h; P-JS, from 9 to 5 g/24 h; and controls, from 6 to 7 g/24 h. Although the integrated blood glucose value did not change after DPRHP, the integrated serum C-peptide value decreased after DPRHP (P<.02). After P-JS, the integrated blood glucose value decreased (P<.02), but there was no change in integrated serum C-peptide secretion. Neither integrated blood glucose nor C peptide values were affected in controls. Insulin dependency increased (22% to 33%) after DPRHP. Pancreatic polypeptide secretion decreased only after DPRHP (P=.003).

CONCLUSIONS

Surgery for chronic pancreatitis does not influence exocrine pancreatic function after either a drainage (P-JS) or a resection procedure (DPRHP). Clinical endocrine function is not affected after DPRHP but improves after P-JS.

Effect of neurotensin on colorectal motor and sensory function in humans

PURPOSE

Animal studies have shown that neurotensin stimulates colonic motility, but little is known on the effect on rectocolonic function in humans. This study was designed to investigate the effect of neurotensin on rectal and colonic motor and sensory function and colonic reflexes in humans.

METHODS

Motor and sensory function of the descending colon and rectum were studied in eight healthy volunteers (5 females; age range, 20-58 years) by using a dual, computerized, rectocolonic, barostat assembly. Measurements were performed during placebo and neurotensin infusion (5 pmol/kg per minute), respectively. Compliance and reflex mechanisms were assessed in both rectum and descending colon. Symptom perception (urge and pain) was scored using Visual Analog Scales (0-10 cm).

RESULTS

Neurotensin significantly (P < 0.05) increased rectal compliance (from 9 +/- 1.1 to 10.1 +/- 1.1 ml/mmHg) and colonic compliance (from 7.9 +/- 0.4 to 9 +/- 0.7 ml/mmHg) during stepwise distensions. Intensity of urge and pain perception during rectal distension was increased by neurotensin (P < 0.05). Sensations during colonic distensions were not altered by neurotensin. For colonic reflexes, during rectal distension the colonic bag volume increased significantly (P < 0.05), whereas during colonic distension rectal bag volume decreased significantly (P < 0.05). Neurotensin delayed the occurrence of these reflexes: they were present at significantly higher pressures compared to placebo (P < 0.05).

CONCLUSIONS

We demonstrated the presence of both a rectocolonic inhibitory and a colorectal stimulatory reflex in healthy volunteers. Neurotensin increases compliance and modulates rectal but not colonic sensitivity. Colorectal and rectocolonic reflexes are impaired during infusion of neurotensin.

Chronic pancreatitis: relation between function and morphology

BACKGROUND

In our department, we routinely use a combined exocrine-endocrine function test to evaluate the pancreatic function in chronic pancreatitis i.e. urinary para amino benzoic acid (PABA) recovery and pancreatic polypeptide secretion in response to a meal and glucose tolerance test.

AIM

To study the relationship between changes in morphology and exocrine/endocrine function in patients with chronic pancreatitis.

PATIENTS AND METHODS

In 103 patients with chronic pancreatitis seen by our department for evaluation of pancreatic function between 1989 and 1999, we retrospectively analysed the correlation between morphology (Cambridge-score) and function. Furthermore the differences in presentation, function and morphology between patients with alcohol-induced chronic pancreatitis and idiopathic chronic pancreatitis were evaluated.

RESULTS

Significant correlation were found for both PABA recovery and pancreatic polypeptide secretion with morphologic score, respectively r = -0.205 (P = 0.037) and r = -0.209 (P = 0.031), but not with endocrine function. The correlation between morphology and PABA recovery or pancreatic polypeptide secretion was observed in the subgroup with alcohol-induced chronic pancreatitis but not in those with idiopathic chronic pancreatitis. Pain is a prominent symptom of chronic pancreatitis. Pain was more frequent and more severe in patients suffering from chronic pancreatitis caused by alcohol or idiopathy.

CONCLUSIONS

Morphology and exocrine function correlate in patients with alcohol-induced chronic pancreatitis but not in patients with chronic pancreatitis. When compared to patients with chronic pancreatitis of idiopathic origin, patients with alcoholic origin show differences in presentation and morphology but not in function.