Pseudohypoglycemia

Abstract

Pseudohypoglycemia is defined as a patient having apparent hypoglycemia. We describe these syndromes as pseudohypoglycemia type 1 (PHG-1) and pseudohypoglycemia type 2 (PHG-2), respectively. PHG-1 usually refers to when the individual may be displaying symptoms suggestive of hypoglycemia, but the plasma sugar levels are greater than 70 mg/dL. Patients with diabetes and chronic hyperglycemia can present with primarily adrenergic symptoms of hypoglycemia at relatively higher serum glucose levels during periods of aggressive glucose control, sometimes labeled as relative hypoglycemia. However, we can extend the definition to also include a variety of patients presenting with sugar values below 70 mg/dL but no symptoms of hypoglycemia. This scenario could be labeled as pseudohypoglycemia type 2 (PHG-2), with minimal symptoms. For PHG-2, one must always rule out technical/methodological errors first. Increased glucose utilization or extraction peripherally via erythrocytes or leucocytes must also be considered. A careful history and understanding glucose measurement and glucose metabolism will greatly help the clinician manage these phenomena.