Uncooked cornstarch treatment for hepatic phosphorylase kinase deficiency.

A 5-year-old boy with short stature, hepatomegaly and motor weakness due to hepatic phosphorylase kinase deficiency is described. Laboratory data showed mild hypoglycaemia and metabolic acidosis, hepatic dysfunction, and a low insulin-like growth factor-I level. Mild hypoglycaemia, marked ketosis and insufficient growth hormone secretion were revealed at night. Serum total and free carnitine levels were low and the acyl/total carnitine ratio was high. Urinary acylcarnitine profile using fast atom bombardment and tandem mass spectrometry showed increased excretion of acetylcarnitine and dicarboxylylcarnitines. These endocrinological and metabolic abnormalities and clinical symptoms were improved with uncooked cornstarch treatment.