No abstract

A not previously reported increase of intestinal permeability to mannitol, clear-cut and not associated with that of the larger probe, is found in type I uncomplicated diabetes mellitus. These results may describe a primary feature of type I diabetes mellitus and the initial steps of evolution to celiac disease.

5-Fluorouracil (5-FU), in association with leucovorin (LV), is the most used chemotherapy agent in the treatment of colorectal cancer. Response rate, as well as side-effect incidence, increases with the dose intensity of regimens that are used. The most common dose-limiting toxicity for 5-FU/LV modulation is diarrhea. To assess the modification of small intestinal function, we investigated the changes in intestinal permeability (IP) and intestinal absorption (IA) in 41 chemo-naive patients (21 men and 22 women; mean age, 61 +/- 9 years) with advanced colorectal cancer after treatment with the association of folinic acid and 5-FU. After chemotherapy administration, we found a marked increase in IP and a reduction in IA, measured as cellobiose-mannitol (CE-MA) ratio (p < 0.0001) and D-xylose absorption (p = 0.0001), respectively. Patients who experienced diarrhea have an increase in CE-MA ratio and a reduction in D-xylose absorption values, both statistically significant. Cellobiose-mannitol ratio and D-xylose absorption tests can be used for the assessment of toxic effect of 5-FU on mature intestinal epithelium and also for evaluating the role of cytoprotective agents.

Malnutrition and absence of exogenous luminal nutrients in the gastrointestinal tract affect intestinal permeability (IP) leading to an increased penetration of substances that passively cross intestinal epithelium via intercellular pathways. We hypothesised that an increase in IP could occur in patients with anorexia nervosa because of their prolonged fasting and chronic malnutrition. Therefore, we assessed IP in 14 drug-free anorexic women and 19 drug-free agematched healthy women by means of the lactulose/mannitol (LA/MA) test. To this purpose, after an overnight fast, subjects ingested an oral solution containing 5 g lactulose and 2 g mannitol in 100 ml water. Urine specimens were collected immediately before and 30, 60, 120, 180, 240 and 300 min after the ingestion of the sugar solution. Urinary lactulose and mannitol were determined by high-performance anion exchange chromatography coupled with pulsed amperometric detection. We found that IP, as expressed by the 5-h LA/MA excretion ratio, was significantly decreased in anorexic women because of a lower urinary recovery of lactulose. Moreover, in patients, the time course of lactulose excretion significantly differs from healthy controls. These results do not confirm our hypothesis of increased IP in anorexia nervosa. Since IP reflects the anatomo-functional status of intestinal mucosa, the present findings support the idea that changes in the anatomo-physiology of intestinal mucosa occur in anorexia nervosa.