Aldosterone:Renin Ratio
Also known as: ARR
Use
Screening test for primary aldosteronism in higher risk groups of hypertensive patients
Special Instructions
Patients should maintain an unrestricted dietary salt intake before testing. Avoid taking drugs that affect the ARR such as spironolactone and certain diuretics at least four weeks prior to sample collection. Blood should be collected mid-morning after the patient has been upright for at least two hours and seated for 5 to 15 minutes before the draw.
Limitations
Several factors can produce false positive or negative ARR results. These include certain medications like diuretics, NSAIDs, ACE inhibitors, as well as conditions such as hypokalemia, sodium-loading, renal impairment, and advancing age. Therefore, the ARR should be considered a preliminary test and followed by confirmatory tests if needed.
Methodology
Mass Spectrometry
Biomarkers
LOINC Codes
- 55151-5
- 1763-2
- 2915-7
- 30894-0
Result Turnaround Time
4-7 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.5 mL
Container
Red-top tube or gel-barrier tube
Collection Instructions
Collect blood mid-morning, after the patient has been up (sitting, standing, or walking) for at least two hours and seated for 5 to 15 minutes. Transfer separated serum to a plastic transport tube and label "Serum−Aldosterone."
Patient Preparation
Maintain an unrestricted dietary salt intake prior to testing. Avoid medications that affect the ARR for at least four weeks.
Storage Instructions
Refrigerated
Other tests from different labs that may be relevant