ABSTRACT
There are a few documented genetic errors of metabolism involving fructose. Fructose-1-phosphate aldolase catalyzes the conversion of fructose-1-phosphate to D-glyceraldehyde and dihydroxyacetone phosphate. In 1956 the first case of hereditary fructose intolerance was reported in a 24-year-old woman. Hypoglycemia, which is responsible for the unconsciousness or even coma seen in some patients with hereditary fructose intolerance, is unresponsive to glucagon and results from inhibition of glycogen breakdown by accumulated fructose-1-phosphate. The enzymes including fructose-1,6-diphosphatase and glucose-6-phosphatase needed to be examined to distinguish the fructose-intolerant children. Fructosuria occurs only after consumption of fructose-containing foods. A deficiency of fructose-1,6-diphosphatase, which removes phosphate from the 1-position of fructose-1,6-diphosphate, is responsible for this hereditary defect. The fructose intolerance test can differentiate fructose intolerance from other acute liver diseases. Accumulation of fructose-1-phosphate in the intestinal mucosa may be the cause of reduced glucose absorption. Fructose-1-phosphate and fructose-1,6-diphosphate aldolase activities were measured in both normal and hereditary fructose-intolerant patients.
