Angiotensiniicsfmcnc

Published: August 9, 2026Updated: August 16, 2026

This test measures the level of angiotensin II, a hormone that affects blood pressure, in the fluid surrounding the brain and spinal cord.

Quick summary

{"Angiotensin II is a hormone that helps regulate blood pressure and fluid balance","This test requires a lumbar puncture (spinal tap) to collect cerebrospinal fluid","The test is usually done for research purposes or to study certain brain and nervous system conditions","Results help doctors understand how the renin-angiotensin system works in the central nervous system","This is a specialized test not commonly ordered for routine diagnosis"}

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC: 1859-8
Short code: ANGII-CSF
Synonyms: Angiotensin II CSF-mCnc
Category: chemistry
Sample: csf
Container: Sterile CSF collection tube (polypropylene); aliquot into cryovial for frozen storage.
Units: N/A
Fasting: false
Population: adult
Sex: all
Age range: 18–99 years
Method: Radioimmunoassay (RIA) or Enzyme-Linked Immunosorbent Assay (ELISA)
CPT: 82164
SNOMED: 104686000
Specimen volume: 1-2 mL of cerebrospinal fluid
Stability: Frozen at -20°C or below for up to 30 days; avoid repeated freeze-thaw cycles. Angiotensin II is rapidly degraded at room temperature.
Hemolysis max: 200
TAT: 48–168 hours
Order: routine

What is this test?

The Angiotensin II test measures the amount of a hormone called angiotensin II in your cerebrospinal fluid (CSF). CSF is the clear, protective fluid that surrounds your brain and spinal cord. Angiotensin II is part of the renin-angiotensin system, which plays a key role in controlling blood pressure and fluid balance in your body.

Why might I need this test?

This is a specialized test that is not commonly performed. Your doctor may order it for research purposes or to better understand certain neurological conditions. It may help study how the body's blood pressure regulation system interacts with the brain and nervous system. The test is typically ordered by neurologists or researchers investigating disorders that may affect the central nervous system's hormone regulation.

How is the sample collected?

The test requires a procedure called a lumbar puncture, also known as a spinal tap. During this procedure, you will lie on your side or sit up while a healthcare provider inserts a thin needle into your lower back to collect a small amount of cerebrospinal fluid. The area will be numbed with local anesthetic to minimize discomfort. The procedure usually takes about 15-30 minutes.

What do the results mean?

Results from this test are interpreted in the context of your specific clinical situation. Normal reference ranges may vary depending on the laboratory performing the test. Your doctor will explain what your results mean in relation to your overall health and any conditions being investigated. Because this is a specialized test, your healthcare provider will discuss the significance of your specific results with you.

Are there any risks?

The main risk associated with collecting CSF is a headache, which can occur after the lumbar puncture. Less common risks include bleeding, infection, or back pain at the puncture site. Your healthcare team will take steps to minimize these risks. Be sure to discuss any concerns with your doctor before the procedure.

Reference range

No standardized reference range established; results should be interpreted in conjunction with clinical findings and compared to age-matched controls from the performing laboratory.N/A

Specimen: csf

No special patient preparation required. Fasting is not necessary prior to lumbar puncture.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Frequently asked questions

Is this a routine test?

No, this is not a routine test. It is a specialized test that is typically only performed in research settings or to investigate specific neurological conditions. Most patients will never need this test.

How should I prepare for the lumbar puncture?

Your doctor will give you specific instructions. Generally, you should inform your doctor about any medications you are taking, especially blood thinners. You may be asked to empty your bladder before the procedure. Wear comfortable, loose-fitting clothing that allows easy access to your lower back.

Will the lumbar puncture be painful?

The area will be numbed with a local anesthetic, so you should feel minimal pain during the procedure. You may feel some pressure or a brief sting when the numbing medication is injected. After the procedure, you may experience a headache, which can usually be managed with rest and plenty of fluids.

How long does it take to get results?

Results may take several days to a week, as this is a specialized test that requires specific laboratory equipment and expertise. Your healthcare provider will contact you with the results when they are available.

Sources

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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy