Small intestinal permeability.

The noninvasive assessment of small intestinal permeability in humans is now within the capability of any routine biochemistry laboratory. There remain however, many pitfalls for the unwary when performing these tests. Importantly, it has now been shown that normal intestinal permeability relates to geographical location rather than race. Recent studies show that it may be possible to simplify the procedure even further. The main recent focus of interest in measuring intestinal permeability relates to patients with AIDS and inflammatory bowel disease, the effects of nonsteroidal anti-inflammatory drugs on the small bowel, and the use of these tests in the pediatric population and critically ill. Some groups have now started to focus their attention on the possible systemic consequences of increased intestinal permeability, whereas others have shown that increased small bowel permeability results in small intestinal inflammation that may in turn be associated with blood and protein loss.