Response to intestinal provocation monitored by transabdominal ultrasound in patients with food hypersensitivity

Objective Owing to lack of objective measures, the diagnosis of food hypersensitivity may be difficult. The aim of this study was to investigate whether the intestinal response to direct provocation in patients with food hypersensitivity could be recognized by ultrasound. Material and methods Thirty-two patients with chronic abdominal complaints, self-attributed to food hypersensitivity/allergy were included in the study. Via a nasoduodenal tube, the duodenal mucosa was challenged with the suspected food item dissolved in 10 ml water or saline. Using external ultrasound, the sonographic features (wall thickness and diameter of the duodenal bulb and jejunum, peristalsis activity and luminal fluid) were recorded before and during one hour after challenge. Results Sonographic changes were observed after challenge in 14 (44%) of the 32 patients. A positive sonographic response (increased wall thickness, diameter, peristalsis and/or luminal fluid) was significantly related to a positive skin prick test (p=0.008) and a positive double-blind placebo-controlled food challenge (p=0.03). A significant correlation was found between provocation-induced symptoms and wall thickness of the duodenal bulb (r=0.50, p=0.004) or the jejunum (r=0.42, p=0.02). Intra- and interobserver variation of the tracing procedure showed low values. Conclusions Responses of the proximal small intestines to direct provocation (swelling of the wall and exudation of fluid into the lumen) could be visualized by transabdominal ultrasound. This new provocation test could be helpful in the evaluation of patients with food hypersensitivity.     

Contrast-enhanced and targeted ultrasound

Ultrasonic imaging is becoming the most popular medical imaging modality,owing to the low price per examination and its safety.However,blood is a poor scatterer of ultrasound waves at clinical diagnostic transmit frequencies.For perfusion imaging,markers have been designed to enhance the contrast in B-mode imaging.These so-called ultrasound contrast agents consist of microscopically small gas bubbles encapsulated in biodegradable shells.In this review,the physical principles of ultrasound contrast agent mic...     

Gastric accommodation assessed by ultrasonography

Gastric accommodation is important for the understanding of the pathophysiology in functional dyspepsia and is also relevant for symptom generation in other disorders. The term gastric accommodation has at least three different meanings: The accommodation process, the accommodation reflex, and the accommodation response. The gastric accommodation process is a complex phenomenon that describes how the size of the gastric compartment changes in response to a meal. The electronic barostat is considered the gold standard in assessing gastric accommodation. Imaging methods, including MRI, SPECT, and ultrasonography may also be used, particularly in patients who are stressresponsive, e.g. functional dyspepsia patients, as a noninvasive and less stress-inducing method is favourable. Ultrasonography satisfies these criteria as it does not by itself distort the physiological response in stressresponsive individuals.     

Enteroendocrine,Musashi 1 and neurogenin 3 cells in the large intestine of Thai and Norwegian patients with irritable bowel syndrome

Objectives: The prevalence, gender distribution and clinical presentation of IBS differ between Asian and Western countries. This study aimed at studying and comparing enteroendocrine, Musashi 1 (Msi 1) and neurogenin 3 (neurog 3) cells in Thai and Norwegian IBS patients.

Material and methods: Thirty Thai and 61 Norwegian IBS patients as well as 20 Thai and 24 Norwegian controls were included. Biopsy samples were taken from each of the sigmoid colon and the rectum during a standard colonoscopy. The samples were immunostained for serotonin, peptide YY, oxyntomodulin, pancreatic polypeptide, somatostatin, Msi 1 and neurog 3. The densities of immunoreactive cells were determined with computerized image analysis.

Results: The densities of several enteroendocrine cell types were altered in both the colon and rectum of both Thai and Norwegian IBS patients. Some of these changes were similar in Thai and Norwegian IBS patients, while others differed.

Conclusions: The findings of abnormal densities of the enteroendocrine cells in Thai patients support the notion that enteroendocrine cells are involved in the pathophysiology of IBS. The present observations highlight that IBS differs in Asian and Western countries, and show that the changes in large-intestine enteroendocrine cells in Thai and Norwegian IBS patients might be caused by different mechanisms.     

Measurement of gastric emptying of a high‐nutrient liquid by 3D ultrasonography in diabetic gastroparesis

Background Gastric emptying (GE) is delayed in 30–50% of patients with longstanding diabetes. Scintigraphy represents the ‘gold standard’ for measurement of GE, but is associated with a radiation burden. Three‐dimensional (3D) ultrasonography has recently been demonstrated to provide a valid measure of liquid GE in healthy subjects; however, the technique has not been validated in patients with gastroparesis. The primary aim of this study was to compare measurements of GE of a high‐nutrient glucose drink by 3D ultrasonography and scintigraphy in diabetic gastroparesis. Methods Ten patients (eight type 1, two type 2, 6M, 4F, aged 46.1 ± 4.5 years, BMI 29.1 ± 1.6 kg m^?2, duration 19.6 ± 3.3 years) with diabetic gastroparesis [defined as retention at 100 min of solid (100 g minced beef) ≥61% and/or 50% emptying time (T50) of liquid (150 mL 10% dextrose) ≥31 min], were studied. Concurrent measurements of GE by scintigraphy and 3D ultrasonography were performed following ingestion of 75 g glucose in 300 mL water labeled with 20 MBq ^99mTc‐sulfur colloid. Key Results There was no significant difference in GE between the two techniques (T50s: scintigraphy – 103.3 ± 10.0 min VS 3D ultrasonography – 98.8 ± 10.4 min; P = 0.60). There was a significant correlation between scintigraphic and ultrasonographic T50s (r = 0.67, P = 0.03). The limits of agreement for the T50s were ?57.22 min and +48.22 min (mean difference ?4.5 min). Blood glucose after the drink was greater when GE was relatively more rapid (e.g. at t = 60 min; scintigraphy: r = ?0.65, P = 0.04; 3D ultrasonography: r = ?0.78, P = 0.008). Conclusions & Inferences Three‐dimensional ultrasonography appears to provide a valid, and non‐invasive, measure of GE of high‐nutrient liquids in diabetic gastroparesis.     

Is irritable bowel syndrome an organic disorder?

Irritable bowel syndrome(IBS)is a common gastrointestinal disorder that is generally considered to be functional because there appears to be no associated anatomical defect.Stress and psychological factors are thought to play an important role in IBS.The gut neuroendocrine system(NES),which regulates all functions of the gastrointestinal tract,consists of endocrine cells that are scattered among the epithelial cells of the mucosa,and the enteric nervous system.Although it is capable of operating independently from the centra nervous system(CNS),the gut NES is connected to and modulated by the CNS.This review presents evidence for the presence of an anatomical defect in IBS patients,namely in the gastrointestinal endocrine cells.These cells have specialized microvilli that project into the lumen and function as sensors for the luminal content and respond to luminal stimuli by releasing hormones into the lamina propria,which starts a chain reaction that progresses throughout the entire NES.The changes in the gastrointestinal endocrine cells observed in IBS patients are highly consistent with the other abnormalities reported in IBS patients,such as visceral hypersensitivity,dysmotility,and abnormal secretion.