ACE Blood Test: High or Low Results, Normal Range and Sarcoidosis
The essentials
The ACE blood test measures angiotensin-converting enzyme, an enzyme that helps control blood pressure. It is mostly used to help follow sarcoidosis, an inflammatory disease, and sometimes in Gaucher disease. A high result does not prove any disease, and a normal result does not rule sarcoidosis out. Do not confuse the ACE test with ACE inhibitor medicines for blood pressure: these drugs can lower your ACE result, so tell the lab or your doctor if you take one.
What is the ACE blood test and what does it measure?
The test measures the amount of angiotensin-converting enzyme (ACE) in a sample of your blood[1]. ACE is an enzyme that helps control blood pressure by turning angiotensin I into angiotensin II[3]. In sarcoidosis the level can rise and fall as the disease changes[1][3].
Your report may call it "ACE", "serum ACE", "SACE" or "angiotensin converting enzyme". It is an enzyme activity measured in a serum sample, reported in units per liter (U/L)[1][3].
How do I read my ACE result, line by line?
Here is a fictitious report from a person being followed for sarcoidosis.
| Test | Result | Reference range | Flag |
|---|---|---|---|
| Angiotensin-converting enzyme (ACE), serum | 88 U/L | 9-67 U/L | H |
| Calcium, total | 10.8 mg/dL | 8.6-10.3 mg/dL | H |
| Alkaline phosphatase | 92 U/L | 40-129 U/L | - |
| Creatinine | 0.9 mg/dL | 0.6-1.2 mg/dL | - |
- ACE 88 U/L: above the range shown. In a person with sarcoidosis, a high value can mean active disease, and a value that falls on treatment is usually a good sign[1][3]. Alone, it diagnoses nothing.
- Calcium: sarcoidosis can raise blood calcium, so doctors check it at the start of the work-up[2].
- Alkaline phosphatase and creatinine: looked at to screen for liver and kidney involvement[2]. Normal here.
Got an ACE result you do not understand? BloodSense explains each line of your complete report and helps you prepare your questions for the visit.
Get my ACE result explainedWhy would a doctor order an ACE test?
- Sarcoidosis: to help follow the disease and the effect of treatment. People with sarcoidosis may have their ACE level checked regularly[1].
- Gaucher disease: the test may help confirm this rare inherited disorder[1].
- Other granulomatous or inflammatory conditions: as one clue among others when the cause of lung, eye, skin or lymph node problems is unclear[4].
The test is not good enough to diagnose sarcoidosis. The 2020 American Thoracic Society guideline bases the diagnosis on a compatible clinical picture, tissue showing granulomas on biopsy and the exclusion of other causes; it makes no recommendation for ACE testing and lists a raised ACE only as a supporting finding[2]. A review of biomarkers concludes that ACE cannot confirm the diagnosis because of its low sensitivity and specificity, but can help tell active from inactive disease[4].
What is a normal ACE level?
There is no single normal value. It depends on the method, the age and the laboratory[1].
| Source | Range | Unit |
|---|---|---|
| MedlinePlus (US National Library of Medicine)[1] | 9-67 U/L (0.15-1.14 µkat/L) | U/L |
| A UK hospital laboratory, adults over 18[3] | 20-70 U/L | U/L |
The "H" or "L" printed on your report compares your result with your own laboratory's range, so always read it with the range printed next to it.
What does a high ACE level mean?
- Common Active sarcoidosis. ACE is raised in at least 60% of people with active sarcoidosis, and it tends to rise with the extent of the disease and fall in remission[3].
- Possible Diabetes, an overactive thyroid, an overactive parathyroid gland, alcohol-related hepatitis, several lung diseases, nephrotic syndrome, multiple sclerosis and stomach ulcers[1].
- Possible Addison disease and Hodgkin disease, a type of lymphoma[1].
- Rare Gaucher disease, a rare inherited disorder, where the test may help with the diagnosis[1].
The test has real limits. In one study of 72 patients seen in a dermatology clinic, ACE was raised in only 29% of those with sarcoidosis[5]. A normal ACE therefore does not rule sarcoidosis out.
What does a low ACE level mean?
- Common ACE inhibitor medicines for high blood pressure or heart failure, such as lisinopril or enalapril[1]. Captopril markedly lowers ACE activity, and levels usually return to normal in about 12 hours[3].
- Common Steroid treatment (usually prednisone) and treatment of sarcoidosis. ACE is raised in only about 20% of people with sarcoidosis who are on steroids[1][3].
- Possible Chronic liver disease, chronic kidney failure, an underactive thyroid and anorexia nervosa[1].
A low ACE is rarely a problem on its own. Its main importance is that it can hide a real rise.
Is the ACE test the same as an ACE inhibitor?
No. The ACE test measures an enzyme in your blood. ACE inhibitors are medicines that block this enzyme to lower blood pressure. They are linked because the drug lowers the result of the test[1][3].
How should I prepare for an ACE blood test?
- Ask whether you need to fast. MedlinePlus says to follow your provider's instructions, which may mean nothing to eat or drink for up to 12 hours[1].
- Tell the person who takes your blood about every medicine you use, especially ACE inhibitors and steroids, because both lower ACE[1].
- Never stop a medicine on your own before the test. Ask your doctor first[1].
- The sample must be serum. Hemolyzed samples and tubes with EDTA or oxalate are unsuitable, so a lab may ask for a new sample[3].
- Repeat the test in the same laboratory when you are being followed, so results can be compared.
When should I see a doctor?
When to see a doctor
- Emergency: call 911 for severe shortness of breath, chest pain, fainting, a very fast or irregular heartbeat, or sudden loss of vision.
- Within a few days for a dry cough or breathlessness that is getting worse, a red painful eye, new skin lumps, or swollen glands that keep growing, especially if you have a raised ACE result.
- At your next appointment to discuss a high or low ACE result, a long-lasting cough, tiredness, night sweats or unexplained weight loss, and any medicine you take for blood pressure.
Questions to ask your doctor
- Why was the ACE test ordered for me, and what will you do with the result?
- Could my medicines, such as an ACE inhibitor or a steroid, change my result?
- Do I need other tests, such as calcium, a chest X-ray or a biopsy?
- How often should the test be repeated, and in which laboratory?
- Which symptoms should make me call you earlier?
Frequently asked questions
Can a normal ACE level rule out sarcoidosis?
No. ACE is raised in only part of the people with sarcoidosis, so a normal result does not exclude the disease[3][5].
Can ACE inhibitors cause a false low result?
Yes. They can markedly lower the measured ACE activity, so your doctor needs to know about them[1][3].
Does a high ACE mean I have sarcoidosis?
Not by itself. Other conditions can raise it, and the diagnosis rests on symptoms, imaging and usually a biopsy[2][4].
Which other blood tests go with the ACE test?
For suspected sarcoidosis, the ATS guideline suggests baseline calcium, a complete blood count, creatinine and alkaline phosphatase[2].
Is the ACE test used to follow treatment?
It can be, but steroids lower ACE, so doctors read it together with symptoms and imaging[1][3].
Related articles
- Total calciumWhy calcium is checked when sarcoidosis is suspected
- Vitamin DAnother level that can be changed by granulomas
- Parathyroid hormoneA cause of high calcium to tell apart
- CRPA general sign of inflammation
- High blood pressureWhy ACE inhibitors are prescribed
- TuberculosisAnother granulomatous disease to rule out
- MedlinePlus Medical Encyclopedia. ACE blood test. Reviewed October 1, 2025. US National Library of Medicine. medlineplus.gov (accessed October 24, 2026)
- Crouser ED, Maier LA, Wilson KC, et al. Diagnosis and detection of sarcoidosis. An official American Thoracic Society clinical practice guideline. Am J Respir Crit Care Med. 2020;201(8):e26-e51. doi:10.1164/rccm.202002-0251ST (accessed October 24, 2026)
- York and Scarborough Teaching Hospitals NHS Foundation Trust. Angiotensin converting enzyme, clinical biochemistry test directory. yorkhospitals.nhs.uk (accessed October 24, 2026)
- Hofauer B, Thuermel K, Gahleitner C, Knopf A. Biomarkers in autoimmune salivary gland disorders: a review. ORL J Otorhinolaryngol Relat Spec. 2017;79(1-2):43-53. doi:10.1159/000455722 (accessed October 24, 2026)
- Nguyen CTH, Kambe N, Kishimoto I, Ueda-Hayakawa I, Okamoto H. Serum soluble interleukin-2 receptor level is more sensitive than angiotensin-converting enzyme or lysozyme for diagnosis of sarcoidosis and may be a marker of multiple organ involvement. J Dermatol. 2017;44(7):789-797. doi:10.1111/1346-8138.13792 (accessed October 24, 2026)
This page is general information. It does not replace the advice of a doctor, who interprets your results with your symptoms, history and examination.
