SPONTANEOUS hypoglycemia due to insular tumor of the pancreas (nesidioblastoma1) in the neonatal period is a rare disease. My patient was subjected to rather extensive clinical study and, to my knowledge, is the youngest one on record to have been surgically explored in quest of such a tumor. Final corroboration was obtained at autopsy.
The concept of hyperinsulinism is intimately linked with the development of knowledge concerning the internal secretory function of the pancreas and its relation to diabetes. True hyperinsulinism is the antithesis of diabetes (Wilder).2 The discovery of the islet tissue by Langerhans in 18693 and the demonstration that these nests of cells are distinct from the acinar tissue laid the foundation of present knowledge. The experiments in ligation of the ducts by Arnozan and Vaillard,4 showing atrophy of the acinar tissue and persistence of the islets, further proved the distinctive character of the