Global disaccharide intolerance
Overview
an inherited disorder due to a defect in the degradation of lysine, characterized by vomiting, rigidity, and coma, and high levels of ammonia, lysine, and arginine in the blood.
Symptoms
a complex of abdominal symptoms after ingestion of normal quantities of dietary carbohydrates, including diarrhea, flatulence, distention, and pain; it is usually due to deficiency of one or more disaccharidases but may be due to impaired absorption or other causes.
Treatment
The clinical manifestations of enzyme deficiency result from the osmotic diarrhea following ingestion of the disaccharide. The affected individual develops crampy, abdominal distress and distention, relieved by the expulsion of liquid stool and flatus. The severity of the diarrhea varies with the disaccharide load, the degree of deficiency of enzyme activity and any associated/ causal intestinal disease. The clinical diagnosis can be confirmed by direct enzyme assay of jejunal mucosal biopsies or by indirect methods for detecting disaccharide malabsorption (e.g., the breath hydrogen test). Treatment of hereditary deficiencies is usually by elimination diets.