Severe lactic acidosis as a presenting feature of pheochromocytoma.

High plasma concentrations of epinephrine and norepinephrine have the potential for generating substantial hyperlactatemia by virtue of their metabolic and vasoconstrictor effects; both these influences affect lactate metabolism in the direction of overproduction and underutilization. Nonetheless, lactic acidosis is not a recognized presenting feature of pheochromocytoma. In this report, we describe a patient with pheochromocytoma in whom the endogenous outpouring of epinephrine and norepinephrine resulted in severe lactic acidosis that featured prominently in the clinical presentation. Pheochromocytoma should be listed among the clinical entities associated with or predisposing to lactic acidosis.