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GTR Home > Conditions/Phenotypes > Carnitine palmitoyltransferase II deficiency


Excerpted from the GeneReview: Carnitine Palmitoyltransferase II Deficiency
Carnitine palmitoyltransferase II (CPT II) deficiency is a disorder of long-chain fatty-acid oxidation. The three clinical presentations are lethal neonatal form, severe infantile hepatocardiomuscular form, and myopathic form (which is usually mild and can manifest from infancy to adulthood). While the former two are severe multisystemic diseases characterized by liver failure with hypoketotic hypoglycemia, cardiomyopathy, seizures, and early death, the latter is characterized by exercise-induced muscle pain and weakness, sometimes associated with myoglobinuria. The myopathic form of CPT II deficiency is the most common disorder of lipid metabolism affecting skeletal muscle and the most frequent cause of hereditary myoglobinuria. Males are more likely to be affected than females.

Genes See tests for all associated and related genes

  • Also known as: CPT1, CPTASE, IIAE4, CPT2
    Summary: carnitine palmitoyltransferase 2

Practice guidelines

  • ACMG ACT, 2022
    American College of Medical Genetics and Genomics, Newborn Screening ACT Sheet, Increased C16 and/or C18:1 Acylcarnitine, Carnitine Palmitoyltransferase II (CPT II) Deficiency and Carnitine Acylcarnitine Translocase (CACT) Deficiency, 2022
  • ACMG Algorithm, 2022
    American College of Medical Genetics and Genomics, Algorithm, C16 +/- C18:1 Elevated: CPT II or CACT, 2022

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