Epic Test Code LAB179 Angiotensin Converting Enzyme, Serum
Additional Codes
MML Code: ACE
NY State Approved
YesPerforming Laboratory
Mayo Clinic Laboratories in RochesterReporting Name
Angiotensin Converting Enzyme, SMethod Name
Spectrophotometry (SP)
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 7 days | |
Frozen | 180 days | ||
Ambient | 24 hours |
Necessary Information
The use of angiotensin converting enzyme (ACE)-inhibiting antihypertensive drugs will cause decreased ACE values. Patients taking ACE inhibitors, such as captopril and enalapril, will have extremely low or unmeasurable ACE activity. Indicate on the request form if the patient is on ACE inhibitors.
Specimen Required
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.5 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial
Blood Tube Draw Volume
Min 50% draw volume
Specimen Type
SerumSpecimen Minimum Volume
0.5 mL
Reference Values
≥18 years: 16-85 U/L
0-17 years: Angiotensin converting enzyme activity may be 20-50% higher in healthy children compared to healthy adults.
For SI unit Reference Values, see https://www.mayocliniclabs.com/order-tests/si-unit-conversion.html
Report Available
1 to 3 daysDay(s) Performed
Monday through Friday
CPT Code Information
82164
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Gross icterus | Reject |
Useful For
Evaluation of patients with suspected sarcoidosis
Clinical Information
Angiotensin converting enzyme (ACE) is integral to the renin-angiotensin system (RAS), which maintains blood pressure by regulation of fluid volume and vascular tension. Its peptidase action on the decapeptide angiotensinogen I results in the hydrolysis of a terminal histidyl leucine dipeptide and the formation of the octapeptide angiotensin II, a potent vasoconstrictor that increases blood pressure.
ACE activity is increased in sarcoidosis, a systemic granulomatous disease that commonly affects the lungs. In sarcoidosis, ACE is thought to be produced by epithelioid cells and macrophages of the granuloma.
ACE activity reflects the severity of sarcoidosis: 68% positivity in those with stage I sarcoidosis, 86% in stage II sarcoidosis, and 91% in stage III sarcoidosis.
Other conditions such as Gaucher disease, leprosy, untreated hyperthyroidism, psoriasis, premature infants with respiratory distress syndrome, adults with amyloidosis, and histoplasmosis have been associated with increased serum ACE activity.
Interpretation
An elevation in the level of serum angiotensin converting enzyme (ACE), along with radiographic evidence of infiltrates or adenopathy and organ biopsies showing noncaseating epithelial granulomas is suggestive of a diagnosis of sarcoidosis.
Normal, healthy children and infants are known to have ACE activity levels greater than the adult reference interval.
Cautions
Spinal fluid angiotensin converting enzyme (ACE) activity to aid the diagnosis of neurosarcoidosis has been reported; however, there is insufficient evidence to support ACE being used for this purpose.
Specimen Retention Time
7 daysDisease States
- Sarcoidosis
Forms
If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:
-General Request (T239)
-Cardiovascular Test Request (T724)