Upper gastrointestinal endoscopic ultrasonography in gastroenterology

Endoscopic ultrasound is a new technique in which high-frequency, high-resolution real-time ultrasound images are obtained from within the gastrointestinal tract by use of an ultrasound probe incorporated into the tip of a fibreoptic endoscope. Forty patients were scanned for gastrointestinal indications. In six patients the scans were technically unsuccessful, in three of these because of difficulties with the prototype instrument. New information was obtained in 20 patients, later confirmed by other means in 12. Endoscopic ultrasound did not provide any new information in 14 patients. The technique shows considerable promise in patients with pancreatic disorders and gut-wall malignancies. It has the ability to provide images with a spatial resolution unobtainable by other imaging methods.     

Nutritional absorption in short bowel syndrome

Eight patients with a short bowel resulting from intestinal resection and clinically stable for at least one year were studied for 10 days. The diet chosen was lactose-free with a low fiber content and contained 22% of total calories as protein, 32% as carbohydrate, and 46% as fat. Total fluid volume was kept constant, and all patients were in positive nitrogen balance. During the 10-day period, blood chemical concentrations, stool, and/or ostomy volume, urine volume, electrolyte excretion, and calorie and divalent cation absorption were measured. In addition it was determined that fluid restriction during meals did not affect these parameters. In these patients the absorptions of fat, carbohydrate, protein, and total calories were 54%, 61%, 81%, and 62%, respectively. Similarly the absorption of the divalent cations, calcium, magnesium, and zinc, were 32%, 34%, and 15%, respectively. We suggest that patients with short bowel syndrome, who have been stable for at least one year and who can tolerate oral diets, do not need to restrict fat or to separate fluids from solids during their meals. Furthermore, they should increase their oral intake to 35–40 kcal/kg ideal body weight in order to counteract their increased losses. The diet should contain 80–100 g protein/day in order to maintain a positive nitrogen balance and a large margin of safety. In addition, these patients may take oral supplementation of calcium, magnesium, and zinc to maintain divalent cation balance.This work was supported by a grant from the Ontario Ministry of Health PR. 228.     

Automated Irregular Antibody Screening on a Modified 15-Channel Blood-Grouping Machine

Abstract. The addition to a 15-channel blood-grouping machine of two singlechannel antibody screening systems, based on the principles described by Marsh and Lalezari has produced a modified machine capable of detecting most clinically significant irregular blood group antibodies with a sensitivity equal to normal manual screening tests.     

Non-dietary lipid in the intestinal lumen

Lipid in the intestinal lumen is mainly dietary in origin, but there is also an endogenous component from bile, bacteria, and the mucosa (through exudation and cell loss). Perfusion experiments in fasting rats demonstrate that exfoliated cells carry with them into the small intestinal lumen an average of 1.12 mg lipid/30 minutes; lipid classes consisting of phosphatidyl choline (lecithin), triglyceride, cholesterol, cholesterol ester, phosphatidyl ethanolamine, and free fatty acid. Fatty acid also enters the lumen independently of cells by exudation.Since the rate of lipid exfoliation and exudation considerably exceeds the faecal lipid excretion in fasting rats, efficient reabsorption must normally occur. Calculations based on published data suggest the daily exfoliation of 12 to 30 g lipid into the small intestinal lumen of fasting man. When reabsorption is impaired, especially in states of increased cell turnover, endogenous mucosal lipid may account for a significant proportion of faecal lipid, perhaps sufficient to constitute a state of fat-losing enteropathy.