Workup for Hypoglycemia in a 2-Year-Old Child
The workup for hypoglycemia in a 2-year-old should include immediate blood sampling during the hypoglycemic episode for insulin, cortisol, growth hormone, and ketone bodies, followed by a systematic evaluation of potential causes including hyperinsulinism, hormonal deficiencies, and metabolic disorders.
Initial Management of Hypoglycemia
Immediate Treatment
- For mild to moderate hypoglycemia: Administer 15g of fast-acting carbohydrates (adjust to 10g for young children) 1
- For severe hypoglycemia with altered consciousness: Administer glucagon 0.5mg (for children <44 lbs/20kg) subcutaneously or intramuscularly 1, 2
- Position the child on their side to prevent aspiration if unconscious 1
- Recheck blood glucose after 15 minutes; repeat treatment if hypoglycemia persists 1
- Once blood glucose normalizes, provide a meal or snack with both fast-acting and long-acting carbohydrates 1
Diagnostic Workup
Critical Samples During Hypoglycemic Episode
- Blood samples (obtain when blood glucose <50 mg/dL) 3:
- Insulin level
- C-peptide
- Cortisol
- Growth hormone
- Glucose
- Electrolytes
- Beta-hydroxybutyrate (ketones)
- Urine samples:
- Ketone bodies
- Organic acids
Laboratory Evaluation
- Complete blood count
- Liver function tests
- Kidney function tests
- Ammonia level
- Lactate level
- Free fatty acids
- Acylcarnitine profile
- Plasma amino acids
Additional Testing Based on Clinical Suspicion
- Hormonal evaluation:
- ACTH stimulation test (if cortisol deficiency suspected)
- Growth hormone stimulation test
- Thyroid function tests
- Metabolic evaluation:
- Fasting study (if recurrent episodes occur)
- Genetic testing for inborn errors of metabolism
Differential Diagnosis by Age and Presentation
Common Causes in 2-Year-Olds
- Ketotic hypoglycemia - most common cause of hypoglycemia in childhood 3, 4
- Hormonal deficiencies:
- Hypopituitarism
- Adrenal insufficiency
- Inborn errors of metabolism:
- Glycogen storage disorders
- Fatty acid oxidation disorders
- Gluconeogenesis disorders
- Hyperinsulinism:
- Persistent congenital hyperinsulinism
- Insulinoma (rare in this age group)
Timing-Based Assessment
- Fasting hypoglycemia: Consider glycogen storage disorders, fatty acid oxidation disorders, or hormonal deficiencies 5
- Postprandial hypoglycemia: Consider inherited fructose intolerance or glucokinase-activating gene mutations 5
- Exercise-induced hypoglycemia: Consider fatty acid oxidation disorders or exercise-induced hyperinsulinism 5
Management Approach
Immediate Management
- Establish IV access if severe hypoglycemia
- Administer IV glucose (2-5 mL/kg of D10W) for severe cases 6
- Monitor vital signs, neurologic status, and blood glucose hourly 6
Long-term Management
- Treatment depends on underlying cause:
- Ketotic hypoglycemia: Frequent feeding, avoidance of prolonged fasting
- Hormonal deficiencies: Hormone replacement therapy
- Inborn errors of metabolism: Specific dietary modifications, medications
- Hyperinsulinism: Medical therapy (diazoxide, octreotide) or surgical intervention
Prevention of Recurrent Episodes
- Educate caregivers about:
- Recognition of hypoglycemia symptoms
- Proper carbohydrate intake
- Consistent meal timing
- Provide glucagon emergency kit and train family members on administration 1, 2
- Consider bedtime snacks if nocturnal hypoglycemia is a concern 1
- Regular follow-up to adjust management plan
Important Considerations
- Severe hypoglycemia in young children may be associated with cognitive deficits 6
- Recognition of hypoglycemia symptoms is developmental and age-dependent; toddlers may not be able to communicate symptoms effectively 6
- Hypoglycemia workup should be thorough as it represents a treatable cause of mental retardation and seizures 3
- Maintain blood glucose levels >50 mg/dL during evaluation and treatment 3
Remember that obtaining diagnostic samples during the hypoglycemic episode is crucial for accurate diagnosis, as these values may be normal when the child is euglycemic.