 Hyperinsulinism

Hyperinsulinism is excessive or inappropriately sustained insulin action or secretion for the metabolic context. In hyperinsulinaemic hypoglycaemia, insulin secretion is insufficiently suppressed as blood glucose falls. Insulin promotes glucose utilization and storage while restraining endogenous glucose production, so the combination can lower the circulating glucose supply. ^[ref]

The activating glucokinase mutation provides a mechanistic example: changing the beta-cell glucose-sensing system shifts the conditions under which insulin is released. A measured insulin concentration must therefore be interpreted alongside the simultaneous glucose state. A concentration that is unremarkable after a meal can be inappropriate during hypoglycaemia; a single universal numerical cutoff does not describe the whole mechanism.