Spontaneous hypoglycemia is not a disease but an indication of a defect in the metabolism of glucose in the organism. Excellent reviews by Skillern,1 Conn,2 and McQuarrie3,4 have indicated the large number of possible etiologic factors. Several authors have emphasized that hypoglycemia occurring in infants and children is not an uncommon condition. In McQuarrie's3 report, 26 of 43 cases of hypoglycemia of infancy were classified as idiopathic and the author referred to these as "idiopathic infantile hypoglycemosis."
In 1956, Cochrane et al.5 observed that certain hypoglycemic infants treated with a high-protein diet had an increased frequency of hypoglycemic attacks. This clinical observation that protein aggravates some cases of infantile hypoglycemia was supported by the finding of a marked fall in blood sugar in three cases after the administration of the amino acid L-leucine.5 The selection of this particular amino acid was partly fortuitous circumstance