Reversal of debrancher deficiency myopathy by the use of high-protein nutrition.

A child with debrancher deficiency presented with myopathy, recurrent hypoglycemia, and growth failure. Evidence for enhanced gluconeogenesis was demonstrated by low postabsorptive gluconeogenic plasma amino acids, a marked fall in alanine during fasting, and a substantial rise in plasma glucose following protein ingestion. The patient was treated with high-protein nocturnal intragastric therapy, which resulted in marked improvement in exercise tolerance, muscle strength and mass, electromyographic findings, and growth.