Fructose Metabolism Disorders Quiz

• There are two different inborn errors in metabolism that are connected to fructose metabolism.
• In Fructosuria, Fructokinase is either deficient or is functioning at low levels, and if fructose is not phosphorylated, then it does not get trapped inside and can diffuse out of the cell.
• Fructose concentrations stay high in the blood stream, and levels can get so high that renal reabsorption cannot keep up, and fructose spills into the urine.
• In fructose intolerance (fructosemia), there is a deficiency in Fructose 1-phosphate aldolase, and the fructose is phosphorylated and trapped in the cell, but without Aldolase B, Fructose 1-phosphate cannot be converted to useful glycolytic intermediates.
• Fructose 1-phosphate builds up in the cell, and the energy charge goes down in liver cells.
• People with fructose intolerance usually have liver damage.
• The treatment for this disorder is to restrict fructose from the diet.

Test your knowledge about inborn errors in metabolism related to fructose metabolism, including fructosuria and fructose intolerance. Learn about the deficiencies in Fructokinase and Fructose 1-phosphate aldolase, the resulting effects on fructose levels in the blood and cells, and the recommended treatment.