Hyperinsulinemic hypoglycemia in adults

The diagnosis of a hypoglycemic disorder requires a high level of suspicion, careful assessment of the patient for the presence of mediating drugs or a predisposing illness, and, where indicated, methodical evaluation on the basis of well-defined diagnostic criteria. The diagnostic burden is heaviest for healthy-appearing persons with episodes of confirmed neuroglycopenia. Our criteria for insulin mediation of hypoglycemia are: plasma insulin greater than or equal to18 pmol (ICMA [immunochemiluminometric assay]), C-peptide greater than or equal to200pmol& (ICMA), proinsulin greater than or equal to5pmol/L (ICMA), betaOH butyrate, less than or equal to2.7mmol/L and generous (1.4mmol/L) response of plasma glucose to IV glucagon administered when the patient is hypoglycemic. Sulfonylureas, meglitinides and insulin antibodies should be sought in the plasma of any hypoglycemic patient.