It is an enzyme which is produced by kidneys & control activation of angiotensin hormone which in turn stimulates adrenal glands to produce hormone aldosterone. Aldosterone is responsible for maintaining normal sodium & potassium levels in blood, controls blood volume and blood pressure (BP).
What is Direct Renin Concentration (DRC) (plasma) lab test?
This laboratory test is also called plasma renin concentration (PCR) which measures amount of renin in blood. This test is sometimes tested together with aldosterone tests to identify the cause behind abnormal aldosterone production.
Why is DRC plasma lab test done?
The test is done:
In differential diagnosis of individuals with hypertension (increased BP)
Measurement of renin useful in diagnosis of primary aldosteronism (causes high BP)
Used to assess adequacy of steroid substitution in patients with adrenal insufficiency. As renin activity is normal with sufficient supplementation & elevated when steroid substitution is adequate.
Firstly, a blood sample is taken by inserting needle in vein in arm or in specialized medical centers blood is collected from renal (kidney) veins by catheter insertion
The sample collected in air-tight vial or test tube is sent to the laboratory
The technician isolates plasma from the blood sample and tests it for levels of renin in it.
What is purpose of renin blood test?
It is done to find out the cause of hypertension.
What is meant by high renin level?
High renin will indicate kidney disease, blockage of renal artery, Addison’s disease, cirrhosis, excessive bleeding & hypertensive emergency
How are renin levels checked?
Mostly renin and aldosterone levels are tested together. These tests are called plasma renin activity test or aldosterone-renin ratio
Does renin cause high blood pressure?
No, it doesn’t produce effect on BP. Rather it converts inactive angiotensin form to angiotensin 1 which in turn alters blood pressure.
INTERPRETATION OF THE RESULTS:
Normal Renin range: 1.9 to 3.7 ng/ml/hour. Although it may vary with different laboratories.
Its levels can go higher than normal in:
Cirrhosis (late stage scarring of liver)
Addison’s disease (adrenal insufficiency)
Hypokalemia (low potassium)
Its levels can go lower than normal in:
Salt-retaining steroid therapy
Salt-sensitive essential hypertension
ADH therapy (antidiuretic hormone)
You get tested to calculate/determine renin concentration or levels in blood. It is ordered for diagnosis of high blood pressure (hypertension) and primary aldosteronism.