A Screening Method for Liver Glycogen Diseases

The majority of patients with glycogenosis of the liver have one of three types of enzyme deficiency: deficiencyofglucose-6-phosphatase, ofthe debranch-ing enzyme system, or of the phosphorylase system (Illingworth, 1961; Hers and Van Hoof, 1968). The severity of the disease and of its manifestations, such as hypoglycaemia and acidosis, is related to the underlying enzyme defect (van Creveld and Huijing, 1965). Treatment of patients with liver glycogenosis is dietary. The diet aims at reducing the effects of the metabolic disturbance and must vary with the type of enzyme defect (Fernandes and van de Kamer, 1965, 1968). It is important to start dietary management as early as possible, and there-fore to diagnose the disease and the enzyme defi-ciency involved, at an early age. The definitive diagnostic procedure is assay of the enzymes, either in liver tissue or- for debranching enzyme and phosphorylase-in the leucocytes. But it would be useful to have available simpler tests to screen children in whom liver glycogen disease is suspected. Various screening procedures have been recom-mended, such as the epinephrine tolerance tes