From the Guidelines
Elevated Angiotensin-Converting Enzyme (ACE) levels are primarily associated with sarcoidosis, a multisystem inflammatory disorder characterized by granuloma formation, as well as other conditions such as granulomatous diseases, liver diseases, hyperthyroidism, and certain malignancies. The causes of elevated ACE levels can be multifaceted, including:
- Granulomatous diseases such as tuberculosis, histoplasmosis, and coccidioidomycosis
- Liver diseases like cirrhosis, alcoholic liver disease, and primary biliary cholangitis
- Hyperthyroidism
- Gaucher's disease
- Leprosy
- Certain malignancies, particularly lymphomas
- Diabetes mellitus, particularly with microvascular complications Some medications, including corticosteroids and ACE inhibitors, can also affect ACE measurements, with corticosteroids potentially decreasing levels and ACE inhibitors potentially interfering with test results 1, 2, 3. The mechanism behind elevated ACE levels involves increased production by epithelioid cells within granulomas or damaged tissue cells. It's essential to note that while elevated ACE levels can suggest certain conditions, they are not specific enough for definitive diagnosis and should be interpreted alongside clinical presentation and other diagnostic tests. In the context of heart failure, ACE inhibitors have been shown to reduce morbidity and mortality, and their use is recommended in patients with chronic heart failure with reduced ejection fraction (HFrEF) 1, 4. However, ACE inhibitors can also cause angioedema, which is a potentially life-threatening condition, and their use should be avoided in patients with a history of angioedema 5, 2. Overall, the interpretation of elevated ACE levels requires a comprehensive approach, considering both the clinical context and the potential effects of various medications.
From the Research
Causes of Elevated Angiotensin-Converting Enzyme (ACE) Levels
Elevated ACE levels can be caused by various factors, including:
- Sarcoidosis: a condition characterized by the growth of granulomas, which are inflammatory cells that can form in various parts of the body, including the lungs, skin, and eyes 6, 7, 8, 9, 10
- Familial hyperactivity of ACE: a rare, benign condition that can cause extremely elevated ACE activity, which can be confirmed by genetic testing 6
- Other granulomatous diseases: such as silicosis and miliary tuberculosis, which can also cause elevated ACE levels 8
- Interstitial lung disease: certain types of interstitial lung disease, such as granulomatous interstitial lung disease, can cause elevated ACE levels 8
Disease Associations
ACE levels have been studied in various diseases, including:
- Sarcoidosis: elevated ACE levels are found in 60-70% of sarcoidosis patients, and can be used as an aid to diagnosis and disease monitoring 6, 7, 9, 10
- Chronic obstructive lung disease (COPD): ACE levels are typically normal in COPD patients, but may be elevated in some cases 8, 10
- Tuberculosis: ACE levels are typically normal in patients with active cavitary pulmonary tuberculosis, but may be elevated in patients with miliary tuberculosis 8, 10
- Lung cancer: ACE levels are typically reduced in patients with lung cancer 10
- Cystic fibrosis: ACE levels are typically reduced in patients with cystic fibrosis 10