What is the recommended management for a pediatric patient with Hereditary Fructose Intolerance (HFI) due to aldolase B deficiency, presenting with severe hypoglycemic episodes, vomiting, and hepatomegaly after introduction of fructose- or sucrose-containing foods?

Management of Hereditary Fructose Intolerance in Pediatric Patients

Immediately institute lifelong, strict elimination of all fructose, sucrose, and sorbitol from the diet—this is the only treatment required and prevents all symptoms, liver damage, and mortality when adhered to rigorously.

Immediate Dietary Intervention

The cornerstone of management is complete dietary restriction, as no pharmacologic therapy exists or is needed 1, 2. This approach directly addresses the pathophysiology by preventing fructose-1-phosphate accumulation that causes the severe hypoglycemia, hepatic dysfunction, and renal tubular damage.

Acute Phase Management

• Eliminate all fructose sources immediately upon suspicion or diagnosis, even before confirmatory testing, as continued exposure can be life-threatening 1, 3
• Use fructose-free, sucrose-free, and sorbitol-free formulas for infants—soy-based formulas without added sugars are appropriate 2
• Monitor blood glucose closely during the acute phase, as severe hypoglycemia may require intravenous glucose support (never use fructose- or sorbitol-containing IV solutions) 1, 4
• Assess and correct coagulopathy with vitamin K or fresh frozen plasma if bleeding tendency is present, as hepatic dysfunction impairs clotting factor synthesis 1, 4

Long-Term Dietary Management

Restrict dietary fructose to less than 1.5 grams per day 2. This stringent limit is necessary because even trace amounts can trigger symptoms in sensitive individuals.

Allowed Foods (Limited Selection)

• Grain products from endosperm only (white rice, refined wheat products without added sugars) 2
• Very limited vegetables that are naturally low in fructose and sucrose 2
• Protein sources without added sweeteners (plain meats, eggs) 2
• Fats and oils without additives 2

Strictly Prohibited

• All fruits and fruit juices 2, 5
• Table sugar (sucrose), honey, agave, and all natural sweeteners 2
• Sorbitol and other sugar alcohols, as sorbitol converts to fructose 2, 4
• Most vegetables except the very limited allowed list 2
• Any medications or supplements containing fructose, sucrose, or sorbitol as excipients 1, 4

Critical Pitfalls to Avoid

Never prescribe or allow administration of:

• Intravenous solutions containing fructose or sorbitol, which can cause acute life-threatening crisis with hypoglycemia, hepatic failure, and renal shutdown within hours 1, 4
• Sweetened condensed milk for vomiting, a historical error that has caused deaths 1
• Over-the-counter medications without checking inactive ingredients for hidden fructose or sorbitol 4

Multidisciplinary Team Requirements

• Metabolic dietitian consultation is mandatory for initial diet planning and ongoing monitoring 2
• Repeated dietary counseling at regular intervals to ensure compliance, review allowed foods, and address new food products 2
• Family education on reading food labels, identifying hidden sources of fructose/sucrose/sorbitol, and recognizing symptoms of accidental exposure 2

Monitoring and Follow-Up

• Regular assessment of growth parameters (height, weight) to ensure adequate nutrition despite dietary restrictions 5
• Liver function tests periodically to monitor for resolution of hepatomegaly and transaminase elevations 5
• Nutritional status evaluation including micronutrient levels, as the restricted diet may require supplementation 2
• Monitor for hepatomegaly resolution, though some degree may persist even with perfect dietary compliance 5

Prognosis with Treatment

Complete symptom resolution and prevention of liver cirrhosis, renal failure, and death occur with strict dietary adherence 1, 5. The 16 survivors in one series were doing well on fructose-exclusion diet, with only one case of irreversible visual impairment from prior intraocular hemorrhage 1. Even infants placed on fructose-free diets from birth may show some persistent hepatomegaly and fatty liver changes, suggesting minimal endogenous fructose production, but they avoid the severe acute and chronic complications 5.

Key Distinction from Other Metabolic Disorders

Unlike glycogen storage disease type I (which requires frequent feedings, cornstarch supplementation, and active glucose management to prevent hypoglycemia [6-6]), HFI requires only dietary avoidance—no cornstarch, no frequent feedings, no tube feeds are needed once fructose is eliminated. The hypoglycemia in HFI is triggered specifically by fructose exposure, not by fasting itself.