Aldosterone/Renin Activity Ratio
Also known as: A/RA
Use
The Aldosterone/Renin Activity Ratio test is used to screen and diagnose hyperaldosteronism, a condition characterized by an overproduction of aldosterone hormone which can lead to hypertension. The test evaluates the balance between aldosterone and renin levels, which is critical for assessing the metabolic state related to adrenal function, and helps in diagnosing primary aldosteronism.
Special Instructions
For accurate results, it is recommended to collect the specimen midmorning after the patient has been physically active for at least 2 hours and seated for 5-15 minutes. It is important to separate serum from cells as soon as possible or within 2 hours of collection. Both serum and plasma specimens must be submitted together, and storage conditions must be strictly adhered to.
Limitations
The test has not been cleared or approved by the US Food and Drug Administration and is considered a Laboratory Developed Test (LDT) performed in a CLIA certified laboratory. Plasma renin activity may not accurately reflect enzyme activity when angiotensinogen levels are decreased, which can affect the precision of the aldosterone/renin activity ratio. Patients with high sodium intake may have suppressed aldosterone levels which could affect the interpretation of the results. Ensure patient preparation guidelines are followed to minimize false-positive or false-negative results.
New York Approved
Methodology
Immunoassay (CLIA)
Biomarkers
LOINC Codes
- 1763-2
- 30894-0
- 2915-7
Result Turnaround Time
1-5 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.5 mL
Container
ARUP Standard Transport Tube
Collection Instructions
Collect midmorning after patient has been active for at least 2 hours and seated for 5-15 minutes. Use a Serum Separator Tube (SST).
Patient Preparation
Refer to the Additional Technical Information for specific patient preparation recommendations.
Storage Instructions
Frozen
Causes for Rejection
Hemolyzed specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 8 hours |
| Refrigerated | 5 days |
| Frozen | 1 month |