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GTR Home > Conditions/Phenotypes > Renal carnitine transport defect


Excerpted from the GeneReview: Systemic Primary Carnitine Deficiency
Systemic primary carnitine deficiency (CDSP) is a disorder of the carnitine cycle that results in defective fatty acid oxidation. It encompasses a broad clinical spectrum including the following: Metabolic decompensation in infancy typically presenting between age three months and two years with episodes of hypoketotic hypoglycemia, poor feeding, irritability, lethargy, hepatomegaly, elevated liver transaminases, and hyperammonemia triggered by fasting or common illnesses such as upper respiratory tract infection or gastroenteritis. Childhood myopathy involving heart and skeletal muscle with onset between age two and four years. Pregnancy-related decreased stamina or exacerbation of cardiac arrhythmia. Fatigability in adulthood. Absence of symptoms. The latter two categories often include mothers diagnosed with CDSP after newborn screening has identified low carnitine levels in their infants.

Genes See tests for all associated and related genes

  • Also known as: CDSP, OCTN2, SLC22A5
    Summary: solute carrier family 22 member 5

Clinical features


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Practice guidelines

  • ACMG ACT, 2022
    American College of Medical Genetics and Genomics, Newborn Screening ACT Sheet, Decreased C0, Carnitine Uptake Defect (CUD; Primary Carnitine Deficiency), 2022
  • ACMG Algorithm, 2022
    American College of Medical Genetics and Genomics, Algorithm, Carnitine Uptake Defect: Decreased C0 (Free Carnitine), 2022

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