Fructose hereditary intolerance

D-Fructose Fruit juices. Honey. Hydrolysis of cane sugar and of inulin (from the Jerusalem artichoke). Can be changed to glucose in the liver and so used in the body. Hereditary fructose intolerance leads to fructose accumulation and hypoglycemia. 

Deficiency of aldolase B, although this isozyme is not expressed in red blood cells, is responsible for hereditary fructose intolerance, an autosomal recessive dis-... 

T16. Tolan, D. R Molecular basis of hereditary fructose intolerance Mutations and polymorphisms in the human aldolase B gene. Hum. Mutat. 6,210-218 (1995). 

The concentration of free Pj decreases as it may in galactosemia, hereditary fructose intolerance, and glucose 6-phosphatase deficiency. 

Hereditary fructose intolerance is due to aldolase B deficiency and is often diagnosed when babies are switched from formula or mother s milk to a diet containing fructose-based sweetening, such as sucrose or honey. 

Contraindications Symptoms of appendicitis or inflamed bowel, hereditary fructose intolerance, hypersensitivity to any component of the formulation... 

Fructose 1-phosphate aldolase B Hereditary fructose intolerance, vomiting, lethargy, failure to thrive, hepatic failure good prognosis with early diagnosis and fructose restriction... 

Hereditary fructose intolerance (HFI), caused by the deficiency of fructaldolase, and fructose- 1,6-bisphosphatase deficiency. 

Fructose-bisphosphate aldolase, which also acts on fructose-1-phosphate, is the enzyme deficient in hereditary fructose intolerance (HFI, MIM 229 600). 

Table 4.6.7 Pathological values of fructose-l-phosphate and fructose-1,6-bisphosphate in patients with hereditary fructose intolerance (HFI) [36]...

Cause and treatment of hereditary fructose intolerance A deficiency of fructokinase causes a benign condition, but a deficiency of aldolase B causes hereditary fructose intolerance, in which severe hypoglycemia and liver damage can lead to death if the amount of fructose (and, therefore, sucrose) in the diet are not severely limited. 

These enzymes have been found in all plant and animal tissues examined and are absent only from a few specialized bacteria. Three closely related isoenzymes are found in vertebrates.185 186 The much studied rabbit muscle aldolase A is a 158-kDa protein tetramer of identical peptide chains.186 187 Aldolase B, which is lacking in hereditary fructose intolerance, predominates in liver and isoenzyme C in brain.185... 

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. 

Phenylketonuria Alcaptonuria Hyperammonemia I Hyperammonemia II McArdle s syndrome Hypophosphatasia Congenital lactase deficiency Hereditary fructose intolerance Gout... 

Deficiency in fructose metabolism, as in essential fme-tosuria, may be perfectly benign, for one is not interrupting the main line of the glycolytic chain. However, there is one condition, hereditary fructose intolerance, which does cause significant problems. 

Carbohydrate storage diseases include (I.) glycogenoses, (2.) galactosaemia, (3.) hereditary fructose intolerance, and (4.) fructose-1,6-biphosphatase deficiency. 

Hereditary fructose intolerance is caused by an autosomal recessive hereditary defect of the enzyme fructose-l-phosphate aldolase. Whenever fructose is supplied, severe hypoglycaemia and functional disorders occur in the liver, kidneys and CNS. The prevalence is estimated at 1 20,000 births. As with galactose intolerance, the gene which codes aldolase B is also localized on chromosome 9. This enzyme defect causes fructose-l-phosphate to accumulate in the liver and tissue. The cleavage of fructose-1,6-biphosphate is only slightly compromised since the enzymes aldolase A and C are available for this process. The consumption of phosphate and ATP in the tissue results in various functional disorders (i.) inhibition of gluconeogenesis in the liver and kidneys, (2.) increase in lactate in the serum with metabolic acidosis, (3.) decrease in protein synthesis in the liver, and (4.) functional disorders of the proximal tubular cells with development of Fanconi s syndrome, (s. pp 593, 594) (193, 194, 196, 198)... 

Mock, D.M., Perman, J.A., Thaler, MJM., Morris, R.C. Chronic fructose intoxication after infancy in children with hereditary fructose intolerance. A cause of growth retardation. New Engl. J. Med. 1983 309 764-770... 

Odievre, M., Gentil, C., Gautier, M., Alagiile, D. Hereditary fructose intolerance in childhood. Diagnosis, management and course in 55 patients. Amer. J. Dis. Childh. 1978 132 605-608... 

Sucrose (saccharose) Unsuitable in hereditary fructose intolerance, glucose/ galactose malabsorption syndrome, or sucrase-isomaltase deficiency... 

The problems that can result from the administration in total parenteral fluid infusions of D-fructose or sorbitol have been reviewed (4). Either of these can cause life-threatening hypoglycemia, unless glucose is administered concurrently, in patients who have underlying hereditary fructose intolerance. Unless there is a clear clinical history of the condition, it may not be readily identified. In some countries, fructose and D-glucitol (sorbitol) have been eliminated from the pharmacopoeia for this reason. 

Hereditary fructose intolerance affects one in 21 000 persons, and there have been more than 12 severe complications caused by these solutions, several lethal. Since a prior history of fructose intolerance is often not obtained, it has been argued that the use of fructose- and sorbitol-containing infusion fluids must be regarded as offering doubtful advantage but carrying definite lethal risk, and that their use should be discontinued. A modified intravenous fructose tolerance test should at least be carried out before infusions of fructose or sorbitol are giveu (8). 

Hereditary fructose intolerance is an autosomal recessive disorder with reduced activity of aldolase B in the liver, kidney, and small intestine. Ingestion of only a few grams... 

A 16-year-old girl died after an uncomplicated appen-dicectomy (10). She had undiagnosed hereditary fructose intolerance and had been given sorbitol and fructose postoperatively. 

Sachs M, Asskali F, Forster H, Encke A. Wiederholte perioperative Application von Fructose und sorbit bei einer Patientin mit hereditarer fructoserntoleranz (HFI). [Repeated perioperative administration of fructose and sorbitol in a female patient with hereditary fructose intolerance (HFI).] Z Ernahrungswiss 1993 32(l) 56-66. 

Panning B, Piepenbrock S. Kritische Bemerkungen zu Berichten fiber Todesfolle durch hereditare Fructose intoleranz im Erwachsenenalter aus der Sicht der Neuroanasthesie. [Critical comments on reports of fatalities in hereditary fructose intolerance in adulthood from the viewpoint of neuroanesthesia.] Anasth Intensivther Notfallmed 1988 23(4) 217-19. 

Excessive oral fructose consumption (>75g daily) in the absence of dietary dextrose in any form (e.g., sucrose, starch, dextrin, etc.) may cause malabsorption in susceptible individuals, which may result in flatulence, abdominal pain, and diarrhea. Except in patients with hereditary fructose intolerance, there is no evidence to indicate that oral fructose intake at current levels is a risk factor in any particular disease, other than dental caries. ... 

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