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Official Description

Hydroxycorticosteroids, 17- (17-OHCS)

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

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.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The 17-hydroxycorticosteroids (17-OHCS) test is indicated for the evaluation of conditions related to abnormal cortisol production. The following are specific indications for performing this test:

  • Cushing's Syndrome - High levels of 17-OHCS can suggest the presence of Cushing's syndrome, a disorder caused by excessive cortisol.
  • Adrenal Disorders - The test may be used to assess adrenal gland function and diagnose various adrenal disorders.
  • Monitoring Cortisol Levels - It can be utilized to monitor cortisol levels in patients undergoing treatment for conditions related to adrenal function.

2. Procedure

The procedure for measuring 17-hydroxycorticosteroids involves several key steps, which are detailed below:

  • Sample Collection - A blood sample is obtained through venipuncture, which is a procedure where a needle is inserted into a vein to draw blood. This step is crucial as it provides the serum or plasma needed for testing. It is important to collect the blood sample at the optimal time, ideally between 6 am and 11 am, to ensure accurate measurement of 17-OHCS levels.
  • Laboratory Analysis of Blood Sample - The collected serum or plasma is then subjected to quantitative high-performance liquid chromatography-tandem mass spectrometry. This advanced analytical technique allows for precise measurement of 17-OHCS levels in the blood, providing reliable results for clinical interpretation.
  • Urine Sample Collection - In addition to blood testing, a urine specimen is also collected, which can be either a random voided sample or a 24-hour urine collection. The method of collection may depend on the clinical scenario and physician preference.
  • Laboratory Analysis of Urine Sample - The urine specimen is tested using the quantitative phenylhydrazine-sulfuric acid reaction, known as the Porter-Silber test. This method is specifically designed to measure the levels of 17-OHCS in urine, complementing the blood test results.

3. Post-Procedure

After the procedure, patients may be advised to follow specific guidelines based on the type of sample collected. For blood samples, there are typically no special post-procedure care instructions, although patients may be monitored for any immediate reactions to the venipuncture. For urine collections, particularly in the case of a 24-hour collection, patients should be instructed on how to properly collect and store the urine to ensure accurate test results. It is also important to inform patients about the potential effects of medications that may influence test outcomes, such as estrogen, dexamethasone, and certain antibiotics. Results from the 17-OHCS tests will be interpreted by healthcare professionals to guide further diagnostic or therapeutic decisions.

Short Descr ASY HYDROXYCORTICOSTEROIDS17
Medium Descr ASSAY OF HYDROXYCORTICOSTEROIDS 17
Long Descr Hydroxycorticosteroids, 17- (17-OHCS)
Status Code Statutory Exclusion (from MPFS, may be paid under other methodologies)
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 9 - Not Applicable
Multiple Procedures (51) 9 - Concept does not apply.
Bilateral Surgery (50) 9 - Concept does not apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 9 - Concept does not apply.
Co-Surgeons (62) 9 - Concept does not apply.
Team Surgery (66) 9 - Concept does not apply.
Diagnostic Imaging Family 99 - Concept Does Not Apply
CLIA Waived (QW) No
APC Status Indicator Conditionally packaged laboratory tests
Type of Service (TOS) 5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS) T1H - Lab tests - other (non-Medicare fee schedule)
MUE 1
CCS Clinical Classification 233 - Laboratory - Chemistry and Hematology
90 Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number.
Date
Action
Notes
2023-01-01 Note Short and medium descriptions changed.
2013-01-01 Changed Short Descriptor changed.
2004-01-01 Changed Code description changed.
2003-01-01 Changed Code description changed.
Pre-1990 Added Code added.
Code
Description
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