Hereditary fructose intolerance is an inherited metabolic condition that affects a person’s ability to digest a sugar called fructose.
Symptoms include nausea, bloating, abdominal pain, diarrhea, vomiting and low blood sugar (hypoglycemia) after ingesting fructose. Additionally, infants with hereditary fructose intolerance may fail to grow and gain weight at the expected rate (failure to thrive). Repeated ingestion of fructose can cause liver and kidney damage, and continued exposure to fructose can result in more severe symptoms including seizures, coma, and death from liver and kidney failure.
Treatment for this condition involves total elimination of sucrose and fructose from the diet, after which affected individuals can experience a normal quality of life and life expectancy.
This condition is caused by pathogenic (disease-causing) variants in the ALDOB gene. Additionally, hereditary fructose intolerance exhibits autosomal recessive inheritance, meaning both parents must be carriers to have a 25% chance of having a child with the condition. The risk of being a carrier is based on a person’s ancestry or ethnic background. Carriers do not typically show any signs or symptoms.
Other names for this condition include fructosemia and aldolase B deficiency.