Pernilla Jerlstad

Altered levels of fecal chromogranins and secretogranins in IBS: relevance for pathophysiology and symptoms?

OBJECTIVES:Chromogranins (Cg) and secretogranins (Sg) are proteins ubiquitous in secretory cells of the enteric, endocrine, and immune systems, and may reflect activity of these systems. We therefore performed a hypothesis generating study to evaluate the association between fecal levels of CgA, CgB, SgII, and SgIII, with the clinical and pathophysiological phenotype of irritable bowel syndrome (IBS) patients.METHODS:Analyses of CgA, CgB, SgII, SgIII, and calprotectin in fecal samples of 82 IBS patients and 29 healthy controls were performed. All IBS subjects completed validated questionnaires to assess gastrointestinal and psychological symptom severity, and underwent rectal barostat test and colonic transit time measurement.RESULTS:IBS patients demonstrated higher levels of fecal CgA (P=0.009), SgII (P<0.001), and SgIII (P<0.001), but lower levels of CgB (P<0.001) compared with controls. SgII had good discriminative validity to positively identify IBS patients, with an area under the receiver operating characteristics (ROC) curve (AUROC) of 0.86 (95% confidence interval (CI): 0.78–0.94). SgIII and CgB both had fairly good discriminative validity to positively identify IBS patients, with an AUROC of 0.79 (95% CI: 0.71–0.87) and 0.78 (95% CI: 0.69–0.87), respectively. There were negative correlations between the colonic transit time and fecal levels of CgA (r=−0.53, P<0.001), SgII (r=−0.55, P<0.001), and SgIII (r=−0.28, P=0.03). Perceived abdominal pain was moderately associated with levels of CgA (r=0.32, P=0.004), SgII (r=0.31, P=0.006), and SgIII (r=0.24, P=0.04). Calprotectin levels were not associated with the levels of granins or with the clinical or pathophysiological phenotype of IBS patients.CONCLUSIONS:Fecal levels of Cg and Sg may be related to the underlying pathophysiology of IBS and of potential importance for symptoms of the patients. Granins also show promise to serve as future biomarkers of IBS. Further studies are needed to explore the potential role of granins in IBS patients.

What do patients with irritable bowel syndrome know about their disorder and how do they use their knowledge

Irritable bowel syndrome (IBS) is a common disorder for which many patients experience a lack of information. By using a questionnaire, we aimed to explore how much knowledge these patients have, and what they find important to receive information and explanation about. Eighty-six subjects with IBS diagnosed in primary care and referred to a gastroenterologist completed the questionnaire before meeting the gastroenterologist. Approximately 80% had knowledge about IBS, although 55% stated that their knowledge was “just vague.” According to visual analogue scale measurement, knowledge as well as satisfaction with knowledge was poor. Most patients had correct knowledge about IBS. Only 15% considered themselves to be thoroughly informed, and 24% stated that they had not received any information at all. The most important issue they wanted information about was what to do to improve symptoms. Many IBS patients seem to have correct knowledge about IBS; however, they do not consider themselves to have that knowledge, and therefore probably do not feel confident in using their knowledge. Encouraging and supporting patients with IBS could contribute to an increased ability to use their knowledge in a more appropriate way.

Gender Differences in Motility of the Large and Small Intestine in Patients With IBS

Background: Visceral hypersensitivity, and altered gastrointestinal motility and secretion, are considered to be key pathophysiological factors in irritable bowel syndrome (IBS), and of great importance for symptom generation. The symptom pattern differs between female and male IBS patients , with more severe abdominal pain, bloating and constipation in females (Khatai et al. DDW 2010). Whether this can be explained by gender differences in pathophysiological alterations is incompletely understood. Aim: To evaluate potential gender differences in small intestinal motility and secretion, colonic motility and rectal sensorimotor function in patients with IBS. Methods: We included 36 male and 36 female IBS patients, matched for age (mean age 39 (20-64) years), who fulfilled the ROME II criteria. All patients underwent investigations to assess colonic motility (colonic transit time using radiopaque markers), small intestinal motility and secretion (antroduodenojejunal manometry with jejunal transmural potential difference (PD) measurement in the fasting state (3h) and after meal intake (1h)) and rectal sensorimotor function (rectal balloon distensions before and after meal intake; 800kcal; 60% fat). Results: Colonic transit time differed between female and male IBS patients, with slower transit in females (2.1±1.3 (mean±SD) vs. 1.2±0.8 days; p<0.0001). Differences were also found in the small intestinal motility with slower propagation velocity of phase III in females (8.7±4.5 vs. 15±9.4 cm/min; p<0.01), and a tendency towards shorter duration of phase III in females (p<0.1). The motility indices in the jejunum also tended to be lower in female versus male IBS patients, but this only reached statistical significance in the fasting state (last 30 min of phase II) (3310±1040 vs. 4510±2730 mmHg x sec; p<0.05). No gender differences were seen in PD measurements in the small intestine, reflecting chloride secretion, or in rectal compliance, tone or sensitivity. Conclusion: We have demonstrated gender differences in small and large intestinal motility in IBS patients, but not in small intestinal secretion or rectal sensorimotor function. These findings are of potential importance for observed differences in the symptom pattern between male and female IBS patients.

W1327 Exaggerated Rectal Tone Response After Meal Intake in Patients with Irritable Bowel Syndrome with Fecal Incontinence

the methane excretors into 4 different patterns: type 1= constant excretion throughout the breath test; type 2= parallel increase of both gases; type 3= reduction of methane excretion when hydrogen increases; type 4= increase in methane excretion, no hydrogen modification. Presence and severity of bloating, flatulence, abdominal pain and borborygmi were evaluated by a scale where 0=no symptom, 3= severe symptom. We also estimated mouth-to-cecum transit time by the lactulose breath test. Results: The prevalence of methane excretors was similar between IBS-C and IBS-D patients (44% vs 42%, respectively, chi-square=NS). methane excretors in comparison with non-excretors showed no difference in the prevalence of bloating (94% vs 91%), flatulence, (87% vs 83%), abdominal pain (85% vs 89%), borborygmi (85% vs 80%); in the severity of bloating (2±1 vs 2±1), flatulence, (1.5±1 vs 1.4±1), abdominal pain (1.6±1 vs 1.7±1), borborygmi (1.4±0.9 vs 1.5±1); in mouth-tocecum tansit time (115±47 min vs 109±38 min). There was no correlation between severity of each symptom and cumulative methane excretion. However, type 2 methane excretors showed a significantly higher prevalence of bloating. Conclusion: In a large sample of IBS patients there is no association between cumulative methane excretion and prevalence of symptoms, but in the subgroup of patients showing both methane and hydrogen excretion increase after lactulose, bloating is more prevalent.