Aldosterone Test- Why am I having this test?
Aldosterone test is used to check for overactive or underactive adrenal glands, both of which can be caused by various conditions.
What is being tested?
This test measures your aldosterone levels to see if they are abnormal. Aldosterone is a steroid that is produced by the two adrenal glands, which are located at the top of each kidney. Aldosterone directly controls the amount of salt (sodium) that is held by the kidneys and indirectly controls the excretion of potassium. It plays an important role in the control of blood volume and blood pressure.
Overactive adrenal glands will produce too much aldosterone. Underactive adrenal glands will produce too little aldosterone.
What kind of sample is taken?
A blood sample is required for this test. It is usually collected by inserting a needle into a blood vessel. A 24-hour urine sample may also be tested.
How do I collect samples at home?
You may be asked to collect urine samples at home over a certain period of time. Follow instructions from a health care provider about how to collect the samples.
When collecting a urine sample at home, make sure you:
- Use supplies and instructions that you received from the lab.
- Collect urine only in the germ-free (sterile) cup that you received from the lab.
- Do notlet any toilet paper or stool (feces) get into the cup.
- Refrigerate the sample until you can return it to the lab.
- Return the samples to the lab as instructed.
How do I prepare for this test?
You may be asked to arrive well before your testing time so that you can remain in a lying or upright position long enough to establish that as your baseline testing position. Also, there are factors that can affect the results of the test. To get the most accurate results:
- Avoid licorice for at least 2 weeks before the test. Licorice can affect your aldosterone levels.
- Try to reduce stress.
- Avoid activities that take a lot of physical effort.
Tell a health care provider about:
- All medicines you are taking, including vitamins, herbs, eye drops, creams, and over-the-counter medicines.
- Any current or recent illness.
How are the results reported?
Your test results will be reported as values. Your health care provider will compare your results to normal ranges that were established after testing a large group of people (reference ranges). Reference ranges may vary among labs and hospitals. For this test, common reference ranges are:
Blood
- Lying face up (supine): 3–10 ng/dL or 0.08–0.30 nmol/L (SI units).
- Upright
(sitting for at least 2 hours):
- Adult female: 5–30 ng/dL or 0.14–0.80 nmol/L (SI units).
- Adult male: 6–22 ng/dL or 0.17–0.61 nmol/L (SI units).
- Newborn: 5–60 ng/dL.
- Child 1 week to 1 year old: 1–160 ng/dL.
- Child 1–3 years old: 5–60 ng/dL.
- Child 3–5 years old: 5–80 ng/dL.
- Child 5–7 years old: 5–50 ng/dL.
- Child 7–11 years old: 5–70 ng/dL.
- Child or adolescent 11–15 years old: 5–50 ng/dL.
Urine
Adults: 2–26 mcg in 24 hours or 6–72 nmol in 24 hours (SI units).
What do the results mean?
Results within the reference ranges are considered normal. Increased aldosterone levels may indicate:
- Aldosterone-producing adrenal tumor.
- Low sodium.
- High potassium levels.
- Laxative abuse.
- Use of diuretics.
- Pregnancy.
- Renal artery stenosis.
- Cushing disease.
- Stress.
Decreased aldosterone levels may indicate:
- Aldosterone deficiency.
- Steroid therapy.
- Addison disease.
- High sodium levels.
- Toxemia of pregnancy.
- Use of certain blood pressure medicines.
Talk with your health care provider about what your results mean.
Questions to ask your health care provider
Ask your health care provider, or the department that is doing the test:
- When will my results be ready?
- How will I get my results?
- What are my treatment options?
- What other tests do I need?
- What are my next steps?
Summary
- The aldosterone test is used to check for overactive or underactive adrenal glands, both of which can be caused by various conditions.
- A blood sample is required for this test. A 24-hour urine sample may also be tested.
- You may be asked to arrive well before your testing time so that you can remain in a lying or upright position long enough to establish that as your baseline testing position.
- Talk with your health care provider about what your results mean.
