Hartnup disease

Hartnup disease

Biochemistry

Biochemistry and metabolism

Amino acid metabolism

Nitrogen and urea cycle

Citric acid cycle

Electron transport chain and oxidative phosphorylation

Gluconeogenesis

Glycogen metabolism

Pentose phosphate pathway

Physiological changes during exercise

Cholesterol metabolism

Fatty acid oxidation

Fatty acid synthesis

Ketone body metabolism

Metabolic disorders

Cystinuria (NORD)

Hartnup disease

Maple syrup urine disease

Ornithine transcarbamylase deficiency

Phenylketonuria (NORD)

Essential fructosuria

Glucose-6-phosphate dehydrogenase (G6PD) deficiency

Hereditary fructose intolerance

Lactose intolerance

Pyruvate dehydrogenase deficiency

Abetalipoproteinemia

Familial hypercholesterolemia

Hypertriglyceridemia

Glycogen storage disease type I

Glycogen storage disease type II (NORD)

Glycogen storage disease type III

Glycogen storage disease type IV

Glycogen storage disease type V

Mucopolysaccharide storage disease type 1 (Hurler syndrome) (NORD)

Mucopolysaccharide storage disease type 2 (Hunter syndrome) (NORD)

Fabry disease (NORD)

Gaucher disease (NORD)

Metachromatic leukodystrophy (NORD)

Niemann-Pick disease type C

Niemann-Pick disease types A and B (NORD)

Tay-Sachs disease (NORD)

Disorders of amino acid metabolism: Pathology review

Disorders of carbohydrate metabolism: Pathology review

Disorders of fatty acid metabolism: Pathology review

Dyslipidemias: Pathology review

Glycogen storage disorders: Pathology review

Lysosomal storage disorders: Pathology review

Key Takeaways

Hartnup disease is a rare autosomal recessive disorder in which a transport protein necessary for the absorption of neutral amino acids is defective. So, Hartnup disease is associated with impaired absorption of neutral amino acids such as tryptophan, which is responsible for synthesizing vitamin B3. This results in vitamin B3 deficiency, presenting symptoms of pellagra ( diarrhea, dermatitis, dementia), cerebellar ataxia, and seizures.