Disorders of Fructose Metabolism
Hereditary fructose intolerance is an autosomal recessive disease which is manifest at weaning but formal diagnosis is often delayed until late childhood or adult life. Fructose, sucrose and sorbitol present in offending foods and drinks induce hypoglycaemia, hypophosphatemia, acidosis, hyperuricemia and hypermagnesemia. If unrecognized, the disease causes failure to thrive, a reno-tubular syndrome with nephrocalcinosis, jaundice, and ultimately liver injury. Parenteral administration of fructose or its congeners can be fatal. Molecular analysis of the aldolase B gene has revolutionized diagnosis. Treatment by a strict dietary exclusion (supplemented by water-soluble vitamins) is successful and, if instituted in a timely manner, is compatible with a normal life span. Early diagnosis and dietary modification are critical for well-being and normal development in affected children.