Hereditary Fructose Intolerance


Hereditary Fructose Intolerance is an autosomal recessive disease caused by a lack of aldolase B, which leads to the accumulation of fructose-1-phosphate (See Fructose Metabolism - coming soon!).

Fructose-1-phosphate binds free phosphate, thereby acting as a phosphate sink and depleting intracellular stores. The build-up of unmetabolized fructose leads to its presence in the urine, which presents as a reducing substance (fructose sugar) in the urine, despite a negative urine dipstick (no glucose in urine).

Patients become symptomatic only after consuming fructose, so infants often present after consuming fruit, juice, or honey. Symptoms include vomiting, hypoglycemia, jaundice, and eventual liver cirrhosis. Prognosis is poor in comparison to Essential Fructosuria.

Find Hereditary Fructose Intolerance and other Metabolic Disorders among Pixorize's visual mnemonics for the USMLE Step 1 and NBME Exams.