CPT® Code 82615

The CPT® Code 82615 refers to a laboratory test that qualitatively assesses the presence of two specific amino acids, cystine and homocystine, in urine. Cystine is formed from the breakdown of the amino acids lysine, ornithine, and arginine. Under normal circumstances, cystine is reabsorbed by the kidneys; however, when this process is impaired, cystine can accumulate and precipitate in the urine, leading to the formation of kidney stones. This condition is known as cystinuria, which is typically attributed to an inherited genetic disorder affecting the renal tubular reabsorption of cystine. On the other hand, homocystinuria is associated with metabolic disorders related to the amino acid methionine, which may arise from deficiencies in specific enzymes, such as cystathionine beta synthase, or from vitamin B deficiencies, including B2, B6, B9, and B12. Elevated levels of homocystine can manifest in a variety of multisystemic symptoms, which may include disorders affecting connective tissues, muscles, the central nervous system, and cardiovascular health. To perform this test, a urine sample is collected, either through a voided specimen or catheterization, and is subsequently analyzed for the presence of cystine and homocystine using spectrometry techniques.