Glycerol-3-phosphate excretion in fructose-1,6-diphosphatase deficiency.

A patient aged 23 months with fructose-1,6-diphosphatase deficiency is reported. This infant demonstrated an increased urine excretion of glycerol-3-phosphate during episodes of hypoglycaemia. The excretion of this compound has not previously been described in this disease or in those disorders associated with a deficiency in one of the other three gluconeogenic enzymes associated with hypoglycaemia. Its presence in the urine from patients may be useful in diagnosis.