The pathophysiology of “happy” hypoglycemia

Abstract

Background Hypoglycemia usually includes various neurological symptoms, which are the consequence of neuroglycopenia. When it is severe, it is associated with altered mental status, even coma. Case presentation We report the case of a patient with severe hypoglycemia, completely asymptomatic, due to the increase of lactate production in response to tissue hypoperfusion following a hemorrhagic shock. This illustrates that lactate can substitute glucose as an energy substrate for the brain. It is also a reminder that this metabolite, despite its bad reputation maintained by its role as a marker of severity in critical care patients, has a fundamental role in our metabolism. Conclusions Following the example of the “happy hypoxemia” recently reported in the literature describing asymptomatic hypoxemia in COVID-19 patients, we describe a case of “happy hypoglycemia.”