Pyruvate carboxylase (PC) deficiency is a rare neurometabolic disorder characterized by metabolic acidosis, failure to thrive, developmental delay, and recurrent seizures at an early age in severely affected patients. The disease is pyruvate carboxylase deficiency disease (MONDO_0009949). Also known as: Leigh necrotizing encephalopathy due to pyruvate carboxylase deficiency, Leigh syndrome due to PC deficiency, Leigh syndrome due to pyruvate carboxylase deficiency, ataxia with lactic acidosis type 2, ataxia with lactic acidosis type II, deficiency of pyruvic carboxylase.