Angiotensin Converting Enzyme (ACE), Cerebrospinal Fluid

CPT: 82164
Print Share

Expected Turnaround Time

4 - 5 days

Related Documents

Specimen Requirements


Cerebrospinal fluid (CSF), frozen


0.5 mL

Minimum Volume

0.2 mL


Plastic (CSF) tube


Collect CSF by lumbar puncture.

Storage Instructions

Transport frozen.

Stability Requirements



Room temperature

14 days


14 days


14 days

Freeze/thaw cycles

Stable x3

Causes for Rejection


Test Details


Quantitative measurement of ACE in CSF. Angiotensin Converting Enzyme (ACE) is used in the assessment of neurosarcoidosis. The major sources of ACE are macrophages and epithelial cells. Patients with sarcoidosis display elevated levels of ACE.


Results of this test are labeled for research purposes only by the assay's manufacturer. The performance characteristics of this assay have not been established by the manufacturer. The result should not be used for treatment or for diagnostic purposes without confirmation of the diagnosis by another medically established diagnostic product or procedure. The performance characteristics were determined by LabCorp.


Quantitative spectrophotometry

Reference Interval

See table.


Range (U/L)

0 to 5 y

Not established

6 to 17 y


18 to 50 y


>50 y


Additional Information

Angiotensin-converting enzyme catalyzes the formation of angiotensin II by cleaving the C-terminal histidylleucine dipeptide from angiotensin I.1

Indications are that ACE is affiliated with an autonomous renin-angiotensin system of the brain that participates in physiologic processes inside the brain.2,3 Also, studies suggest that changes in ACE concentrations in brain tissue, caused by various neurologic disorders, are reflected by alterations in ACE activity in cerebrospinal fluid (CSF).4

Increased ACE concentrations in CSF are associated with neurosarcoidosis,4-7 with affected patients generally having activities approximately two-fold or more higher than those of healthy individuals.4,6,7

Increased CSF ACE has also been implicated in neurologic diseases, such as bacterial and viral meningitis and Behcet disease.4-7

Decreased concentrations have been reported in patients with Alzheimer disease, Parkinson disease, and progressive supranuclear palsy.8,9


1. Soffer RL. Angiotensin-converting enzyme and the regulation of vasoactive peptides. Annu Rev Biochem. 1976;45:73-94.183603
2. Printz MP, Ganten D, Unger T, Phillips MI. Mini review: the brain renin angiotensin system. In: Ganten D, Printz MP, Phillips MI, Scholkens BA, eds. The renin-angiotensin system in the brain. Heidelberg: Springer Verlag, 1982:3-52.
3. Phillips MI, Weyhenmeyer J, Felix D, Ganten D, Hoffman WE. Evidence for an endogenous brain renin-angiotensin system. Fed Proc. 1979 Aug;38:2260-2266.222621
4. Schweisfurth H, Schioberg-Schiegnitz S. Assay and biochemical characterization of angiotensin-I-converting enzyme in cerebrospinal fluid. Enzyme. 1984;32(1):12-19.6090116
5. Chan Seem CP, Norfolk G, Spokes EG. CSF angiotensin converting enzyme in neurosarcoidosis. Lancet. 1985 Feb 23;1(8426):456-457.2857830
6. Oksanen V, Fyhrquist F, Somer H, Gronhagen-Riska C. Angiotensin converting enzyme in CSF: a new assay. Neurology. 1985 Aug;35(8):1220-1223.2991815
7. Jones DB, Mitchell D, Horn DB, Edwards CR. Cerebrospinal fluid angiotensin converting enzyme levels in the diagnosis of neurosarcoidosis. Scott Med J. 1991 Oct;36(5):144-145.1664971
8. Zubenko GS, Volicer L, Direnfeld LK, Freeman M, Langlais PJ, Nixon RA. Cerebrospinal fluid levels of angiotensin-converting enzyme in Alzheimer's disease, Parkinson's disease and progressive supranuclear palsy. Brain Res. 1985 Mar 4;328(2):215-221.2985183
9. Zubenko GS, Marquis JK, Volicer L, Direnfeld LK, Langlais PJ, Nixon RA. Cerebrospinal fluid levels of angiotensin-converting enzyme, acetylcholinesterase, and dopamine metabolites in dementia associated with Alzheimer's disease and Parkinson's disease: a correlative study. Biol Psychiatry. 1986 Dec;21(14):1365-1381.3024746


Order Code Order Code Name Order Loinc Result Code Result Code Name UofM Result LOINC
123231 ACE, CSF 12480-0 123232 ACE, CSF U/L 12480-0

For Providers

Please login to order a test

Order a Test

© 2021 Laboratory Corporation of America® Holdings and Lexi-Comp Inc. All Rights Reserved.

CPT Statement/Profile Statement

The LOINC® codes are copyright © 1994-2021, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee. Permission is granted in perpetuity, without payment of license fees or royalties, to use, copy, or distribute the LOINC® codes for any commercial or non-commercial purpose, subject to the terms under the license agreement found at Additional information regarding LOINC® codes can be found at, including the LOINC Manual, which can be downloaded at