Fructosuria, essential

Essential fructosuria is a benign, asymptomatic condition arising from deficiency of the enzyme fructokinase that causes a portion of fructose to be excreted in the urine. 

DHAP is a glycolysis intermediate, whereas glyceraldehyde must be reduced by a mitochondrial enzyme, glyceraldehyde dehydrogenase, to glycerol, which is then subject to action by glycerol kinase in the liver. The aldolase seems to be the principal pathway of metabolizing fructose and depends on the initial phosphorylation step catalyzed by fructokinase, which produces fructose-l-phosphate. Fructokinase is defective in an inherited disorder, essential fructosuria. Fructose-l-phosphate aldolase is deficient in the hereditary disorder fructose intolerance. 

Fructokinase is deficient in essential fructosuria therefore, fructose can-s not be metabolized as rapidly as it normally would. Blood fructose levels... 

Essential fructosuria A rare, benign genetic condition in which fructose spills over to the urine because the Uver, kidney, and intestine lack the enzyme fructokinase. 

L8. Levine, R., and Taubenhaus, M., Clinical conference on metabolism problems. Essential fructosuria. Metabolism Clin, and Exptl. 3, 82-87 (1954). 

Essential fructosuria is a rare and benign genetic disorder caused by a deficiency of the enzyme fructok-inase. Why is this disease benign, when a deficiency of aldolase B (hereditary fructose intolerance) can be fatal Could Candice Sucher have essential fructosuria ... 

In essential fructosuria, fructose cannot be converted to fructose 1-phosphate. This condition is benign because no toxic metabolites of fructose accumulate in the liver, and the patient remains nearly asymptomatic. Some of the ingested fructose is slowly phosphorylated by hexokinase in nonhepatic tissues and metabolized by glycolysis, and some appears in the urine. There is no renal threshold for fructose the appearance of fructose in the urine (fructosuria) does not require a high fructose concentration in the blood. 

Essential fructosuria which is a benign condition caused by a deficiency of the enzyme fructokinase. 

See also essential fructosuria, hereditary fructose intolerance... 

Further reading Froesch, E.R. (1978). Essential fructosuria, hereditary fructose intolerance and fructose-1,6-diphosphatase deficiency. In Stanbury, J.B., Wyngaarden, J.B. and Fredrickson, D.S. (eds.) The Metabolic Basis of Inherited Disease. 4th Ed., p. 121. (New York McGraw-Hill)... 

Essential fructosuria is an unrelated and completely harmless condition caused by deficiency of fructokinase [32]. 

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