CPT® Code 83491

The CPT® Code 83491 refers to the measurement of 17-hydroxycorticosteroids (17-OHCS) levels in blood or urine. This test is crucial for assessing the levels of 17-OHCS, which is an inactive byproduct formed during the metabolism of cortisol, a hormone produced by the adrenal glands. The measurement of 17-OHCS is significant as elevated levels can be indicative of Cushing's syndrome, a condition characterized by excessive cortisol production. It is important to note that 17-OHCS levels can fluctuate throughout the day, with the most accurate results typically obtained from samples collected between 6 am and 11 am. Certain medications, including estrogen, dexamethasone, and specific antibiotics such as ampicillin and gentamicin, may influence the levels of 17-OHCS in the blood and urine, potentially leading to elevated test results. The collection of a blood sample for this test is performed through venipuncture, which is a separately reportable procedure. The analysis of serum or plasma is conducted using advanced techniques such as quantitative high-performance liquid chromatography-tandem mass spectrometry. For urine specimens, either a random voided sample or a 24-hour collection can be utilized, with testing performed via the quantitative phenylhydrazine-sulfuric acid reaction, commonly known as the Porter-Silber test.