Miscellaneous Metabolic Disorders

Gene: ALDOB

Green List (high evidence)

Well established gene-disease association.

Clinical symptoms of HFI include gastrointestinal distress (nausea, vomiting, diarrhea, abdominal pain, anorexia), jaundice, bleeding tendency, renal tubular dysfunction and metabolic disturbances following dietary exposure to fructose, sucrose, or sorbitol. If large quantities of fructose are ingested, lethargy, seizures, and/or progressive coma may ensue. Persistent fructose exposure can result in chronic growth restriction, failure to thrive, renal and hepatic failure, and risk of death.

Symptoms appear in infancy at the time of weaning.

Treatment: Lifelong dietary restriction of fructose, sucrose, and sorbitol.

Assessed as 'strong actionability' by ClinGen.

Of particular note, a 24% sucrose solution (routinely administered to hospitalized neonates for minor procedures) should not be given to neonates known to have HFI. This recommendation is supported by case reports of reported accidental and iatrogenic fructose infusion-related serious organ failure events and/or deaths.

Alerts should be placed in the patient's chart or medical record to notify practitioners to the HFI diagnosis and to the medical risks associated with exposures to fructose and related metabolites. The patient is advised to wear at all times a medically approved alert bracelet/necklace that provides information about the diagnosis of HFI.

Evidence from 50 patients presenting with confirmed and symptomatic HFI shows that upon dietary restriction of fructose, the improvement observed is dramatic: vomiting and gastrointestinal symptoms resolved nearly immediately, bleeding tendency resolves in ~24 hours, renal tubular dysfunction can resolve in as little as 3 days, and clinical and biological findings, with the exception of hepatomegaly, resolved within a few weeks. Normal growth occurred in 2-3 years. In the 50 symptomatic patients and 5 patients who received treatment from birth, liver enlargement persisted in spite of treatment and resolution of fibrosis.
Sources: Expert Review

Created: 20 Jul 2023, 11:53 p.m.

Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal

Phenotypes
Fructose intolerance, hereditary, MIM# 229600