CPT® Code 82379

The CPT® Code 82379 refers to a laboratory test that quantitatively measures both total and free carnitine in a specimen. Carnitine is a vital hydrophilic amino acid derivative that plays a crucial role in energy metabolism, particularly in the breakdown of long-chain fatty acids, which are essential for mitochondrial function. This process is critical for the production of energy, as it allows the body to utilize fats for fuel. Carnitine is synthesized in the liver and kidneys and can also be obtained from dietary sources, primarily meats and dairy products. A deficiency in carnitine can lead to significant metabolic issues, as the body may struggle to convert long-chain fatty acids into energy, resulting in a lack of ketones necessary for brain function. Symptoms associated with carnitine deficiency can include hypoglycemia, muscle weakness, anemia, and complications affecting the heart and kidneys. Newborns are routinely screened for primary carnitine deficiency shortly after birth to ensure early detection and management. Additionally, secondary or acquired carnitine deficiency may arise from various conditions, including type 2 diabetes, gastrointestinal disorders, familial cardiomyopathy, renal tubule disease, chronic renal failure, and prolonged use of certain medications such as steroids, antibiotics, anticonvulsants, and total parenteral nutrition (TPN). The test requires a blood sample, which can be collected through a venipuncture or heel stick, and a urine sample, which may be obtained via voided specimen or catheterization. The analysis of serum, plasma, and urine samples is performed using tandem mass spectrometry, a highly sensitive and specific method for quantifying carnitine levels.