Why undergoing this examination?

Hereditary fructose intolerance (HFI) is a disorder of fructose metabolism, resulting from a deficiency in the activity of the enzyme aldolase B (fructose-1-phosphate aldolase). This enzymatic defect prevents the transformation of fructose into its various metabolites, resulting in inhibition of glucose synthesis and a decrease in adenosine triphosphate (ATP). As a consequence, various metabolic alterations such as hypoglycemia, lactic acidemia, hypophosphatemia, hyperuricemia, hypermagnesemia, and hyperalaninemia are observed, along with clinical symptoms such as nausea, vomiting, and abdominal pain. HFI is a genetic disease inherited in an autosomal recessive manner, resulting from mutations in the ALDOB gene. 

What is this exam?

The Fructose Test involves the evaluation of the three recurrent mutations in the ALDOB gene (A149P, A174D, N334K), responsible for 90% of HFI cases in European patients. Alternatively to the breath test, the analysis is performed from a blood sample, avoiding direct patient exposure to substances. 

For whom is it indicated?

• Children with clinical symptoms and nutritional and/or family characteristics suggestive of HFI. 
• Close relatives of patients with HFI. 
• Clinical suspicion of fructose malabsorption. 

Technology

Sanger Sequencing