Carnitine palmitoyltransferase II deficiency is also known as CPT-II deficiency. It leads to excess long-chain fatty acids, as the body lacks the ability to transport fatty acids into the mitochondria to be processed as a fuel source. The disease is caused by a defect in the gene CPT2. This deficiency is present in patients in one of three ways: lethal neonatal, severe infantile hepatocardiomuscular, and myopathic form. Myopathic is the least severe form of deficiency and can be present at any point in the lifespan of the patient. The other two forms appear in infancy. Severe infantile forms and symptoms are liver failure, heart problems, seizures, and death. Muscle pain and weakness are seen in the myopic form. Treatment generally includes dietary modifications and carnitine supplements.