Our knowledge of diseases in humans caused by enzyme deficiency is growing rapidly. One recently recognized condition is "disaccharide intolerance," which results when there is a deficiency of the disaccharidases in the small intestine. Disaccharide intolerance seems to be relatively common and sometimes presents a serious clinical picture, especially in infants. Therefore, it is important that the clinician be able to recognize this syndrome.
There are phenomena in disaccharide intolerances such as hereditary multiple enzyme defects and acquired deficiency of single enzyme activity, which should stimulate research in regard to the formation and action of the intestinal disaccharidases. The literature about intestinal enzyme deficiencies is increasing and several recent reviews have been published.1-3
To understand the enzyme defects underlying the different forms of disaccharide intolerance, one must recognize the specificity of the small intestinal disaccharidases in the human. By means of heat inactivation of these enzymes, I