Hereditary fructose intolerance
Fructose intolerance Classification & external resources
Hereditary fructose intolerance (HFI) or fructose poisoning is a hereditary condition caused by a deficiency of liver enzymes that metabolise fructose. It is also known as hereditary fructosemia, or fructose in the blood (-emia means in the blood)
Additional recommended knowledge
The deficient enzyme is aldolase-B, which converts fructose-1-phosphate to
DHAP and glyceraldehyde. This means that the fructose cannot be further metabolised beyond fructose-1-phosphate. This traps phosphates; which are needed to phosphorylate glycogen phosphorylase which carries on to release units of glucose-1-phosphate from glycogen. (Glucose-1-phosphate gets converted to glucose-6-phosphate and then dephosphorylated to form glucose).
In addition, aldolase-B plays an important role in
gluconeogenesis, producing fructose-1,6-bisphosphate from glyceraldehyde-3-phosphate and DHAP. But, glucose may still be released through the breakdown of glycogen. Although, it cannot be synthesized from gluconeogenesis, resulting in severe hypoglycaemia.
If fructose is ingested, other symptoms such as vomiting,
hypoglycemia, jaundice, hemorrhage, hepatomegaly, hyperuricemia and eventually kidney failure will follow.
Treatment is with a fructose free diet, which if adhered to, is concordant with a good prognosis.
Fructose and sucrose eliminated from diet.
 Related conditions
Hereditary fructose intolerance should not be confused with
fructose malabsorption. The latter is the same as dietary fructose intolerance (DFI), a deficiency of fructose transporter enzyme in the enterocytes, which leads to abdominal bloating, diarrhea and/or constipation.
^ -389021656 at GPnotebook ^ /END101 at FPnotebook
Metabolic pathology / Inborn error of metabolism ( E70-90, 270-279) Amino acid Aromatic ( Phenylketonuria, Alkaptonuria, Ochronosis, Tyrosinemia, Albinism, Histidinemia) - ( Organic acidemias Maple syrup urine disease, Propionic acidemia, Methylmalonic acidemia, Isovaleric acidemia, 3-Methylcrotonyl-CoA carboxylase deficiency) - Transport ( Cystinuria, Cystinosis, Hartnup disease, Fanconi syndrome, Oculocerebrorenal syndrome) - Sulfur ( Homocystinuria, Cystathioninuria) - ( Urea cycle disorder N-Acetylglutamate synthase deficiency, Carbamoyl phosphate synthetase I deficiency, Ornithine transcarbamylase deficiency, Citrullinemia, Argininosuccinic aciduria, Hyperammonemia) - Glutaric acidemia type 1 - Hyperprolinemia - Sarcosinemia Carbohydrate Lactose intolerance - Glycogen storage disease ( type I, type II, type III, type IV, type V, type VI, type VII) - fructose metabolism ( Fructose intolerance, Fructose bisphosphatase deficiency, Essential fructosuria) - galactose metabolism ( Galactosemia, Galactose-1-phosphate uridylyltransferase galactosemia, Galactokinase deficiency) - other intestinal carbohydrate absorption ( Glucose-galactose malabsorption, Sucrose intolerance) - pyruvate metabolism and gluconeogenesis ( PCD, PDHA) -
Pentosuria - Renal glycosuria Lipid storage Sphingolipidoses/ Gangliosidoses: GM2 gangliosidoses ( Sandhoff disease, Tay-Sachs disease) - GM1 gangliosidoses - Mucolipidosis type IV - Gaucher's disease - Niemann-Pick disease - Farber disease - Fabry's disease - Metachromatic leukodystrophy - Krabbe disease
Neuronal ceroid lipofuscinosis ( Batten disease) - Cerebrotendineous xanthomatosis - Cholesteryl ester storage disease ( Wolman disease) Fatty acid metabolism Lipoprotein/lipidemias: Hyperlipidemia - Hypercholesterolemia - Familial hypercholesterolemia - Xanthoma - Combined hyperlipidemia - Lecithin cholesterol acyltransferase deficiency - Tangier disease - Abetalipoproteinemia
Fatty acid: Adrenoleukodystrophy - Acyl-coA dehydrogenase ( Short-chain, Medium-chain, Long-chain 3-hydroxy, Very long-chain) - ( Carnitine Primary, I, II) Mineral Cu Wilson's disease/ Menkes disease - Fe Haemochromatosis - Zn Acrodermatitis enteropathica - PO 4 3�' Hypophosphatemia/ Hypophosphatasia - Mg 2+ Hypermagnesemia/ Hypomagnesemia - Ca 2+ Hypercalcaemia/ Hypocalcaemia/ Disorders of calcium metabolism Fluid, electrolyte and acid-base balance Electrolyte disturbance - Na + Hypernatremia/ Hyponatremia - Acidosis ( Metabolic, Respiratory, Lactic) - Alkalosis ( Metabolic, Respiratory) - Mixed disorder of acid-base balance - H 2O Dehydration/ Hypervolemia - K + Hypokalemia/ Hyperkalemia - Cl �' Hyperchloremia/ Hypochloremia Purine and pyrimidine Hyperuricemia - Lesch-Nyhan syndrome - Xanthinuria Porphyrin Acute intermittent, Gunther's, Cutanea tarda, Erythropoietic, Hepatoerythropoietic, Hereditary copro-, Variegate Bilirubin Unconjugated ( Lucey-Driscoll syndrome, Gilbert's syndrome, Crigler-Najjar syndrome) - Conjugated ( Dubin-Johnson syndrome, Rotor syndrome) Glycosaminoglycan Mucopolysaccharidosis - 1:Hurler/ Hunter - 3:Sanfilippo - 4:Morquio - 6:Maroteaux-Lamy - 7:Sly Glycoprotein Mucolipidosis - I-cell disease - Pseudo-Hurler polydystrophy - Aspartylglucosaminuria - Fucosidosis - Alpha-mannosidosis - Sialidosis Other Alpha 1-antitrypsin deficiency - Cystic fibrosis - Amyloidosis ( Familial Mediterranean fever) - Acatalasia