Fructose Intolerance

Clinical Characteristics
Ocular Features: 

Dense cataracts have been reported in the first decade of life in several patients.

Systemic Features: 

Abdominal pain, vomiting and hypoglycemia usually appears in infancy upon the introduction of fructose or sucrose to the diet.  Some infants have a more severe reaction to such sugars with lethargy, seizures and coma.  Older children and adults develop a protective aversion to fruits and sweets.  Chronic ingestion leads to liver cirrhosis, renal tubule damage, growth retardation, and even malnutrition.  Adults may also have hypoglycemia and metabolic acidosis when challenged with sucrose and fructose.

Genetics

This is an autosomal recessive disorder resulting from mutations in the ALDOB gene (9q31.1).  However, several heterozygous patients with symptoms have been reported and such individuals may be predisposed to hyperuricemia.  Multiple mutations have been identified in the ALDOB gene.

Treatment
Treatment Options: 

Treatment with a fructose restricted diet is highly effective but must be strictly enforced to allow normal growth.

References
Article Title: 

Hereditary fructose intolerance

Ali M, Rellos P, Cox TM. Hereditary fructose intolerance. J Med Genet. 1998 May;35(5):353-65. Review.

PubMed ID: 
9610797

References

Ananth N, Praveenkumar GS, Rao KA, Vasanthi, Kakkilaya S. Two cases of hereditary fructose intolerance. Indian J Clin Biochem. 2003 Jul;18(2):87-92.

PubMedID: 23105397

Ali M, Rellos P, Cox TM. Hereditary fructose intolerance. J Med Genet. 1998 May;35(5):353-65. Review.

PubMedID: 9610797

Sitadevi C, Ramaiah Y, Askari Z. Fructose intolerance associated with congenital cataract. Report of a case. Indian J Pediatr. 1968 Oct;35(249):496-8.

PubMedID: 5719655