Fructose Intolerance

Abstract

Fructose intolerance is a genetically determined metabolic disorder inherited as an autosomal recessive. It is probably as common as the more widely recognized galactose intolerance. In affected individuals fructose given orally or intravenously causes profound hypoglycaemia, with a rise of the level of fructose in the blood to 20 mg./100 ml. or more. The essential abnormality is an absence of the liver enzyme fructose-l-P. aldolase. The condition may present in infancy as neonatal jaundice with hepatomegaly, or with vomiting and failure to thrive: in older children hypoglycaemic fits may occur or glycogen storage disease may be suspected on account of the enlarged liver. In adults the symptoms are less obvious, and may be dismissed as “neurotic ill-health.” The diagnosis is made by an oral or I.V. fructose tolerance test or by estimation of the activity of the specific aldolase in a fresh or frozen liver biopsy. Treatment is by the exclusion of fructose and sucrose from the diet. Five children with this condition are described. © 1967, British Medical Journal Publishing Group. All rights reserved.