CPT® Code 82128

The CPT® Code 82128 refers to a laboratory test that is designed to detect the presence of multiple amino acids in a specimen, which can be either blood or urine. Amino acids are essential organic compounds that serve as the building blocks of proteins and play a critical role in various metabolic processes within the body. This test is particularly relevant for individuals suspected of having an inborn error of metabolism, a group of genetic disorders that disrupt normal metabolic pathways. The clinical manifestations of these disorders often present in infancy or early childhood and can vary significantly based on the specific amino acid that is affected. Symptoms may include feeding difficulties, poor growth or failure to thrive, seizures, muscle weakness, renal or liver dysfunction, developmental delays, and cognitive impairments. To perform the test, a blood sample is typically collected through venipuncture, which is a procedure that involves puncturing a vein to obtain blood. Alternatively, a urine sample can be collected either through a voided specimen or via catheterization, depending on the clinical scenario. The analysis of the samples is conducted using advanced techniques such as liquid chromatography-tandem mass spectrometry, which allows for precise identification and quantification of amino acids. It is important to note that if the test is specifically measuring the quantitative amount of a single amino acid, the appropriate code to report would be CPT® Code 82131. Quantitative amino acid testing is particularly useful for monitoring treatment and dietary compliance in patients with conditions such as phenylketonuria (PKU), cystinuria, and Hartnup disease, which are all disorders related to amino acid metabolism.