From the Guidelines
Aldolase levels are not typically used to diagnose or monitor muscle damage or muscular dystrophy, as creatine kinase (CK) is the more commonly used and reliable marker for muscle damage. When evaluating patients with suspected muscular dystrophies, polymyositis, dermatomyositis, or rhabdomyolysis, CK levels are usually assessed, as they are more specific and sensitive for muscle damage 1. However, aldolase levels can provide complementary information in certain clinical scenarios, particularly when CK levels are normal or mildly elevated, and there is a high suspicion of muscle damage or disease.
Key Points to Consider
- Aldolase is an enzyme found primarily in muscle and liver tissue, and elevated levels can indicate damage to these cells.
- The test requires a simple blood draw, and normal values typically range from 1.0 to 7.5 units per liter, though reference ranges may vary between laboratories.
- Aldolase levels should be interpreted alongside other clinical findings and laboratory tests, such as CK levels, for accurate diagnosis and management of the underlying condition.
- In cases of immune-related myositis, aldolase levels may be used in conjunction with CK levels to guide management and treatment decisions, as outlined in the ASCO guideline update 1.
Clinical Application
In clinical practice, the decision to obtain an aldolase level should be based on the individual patient's presentation and the suspected underlying condition. For example, in patients with suspected muscular dystrophy, the diagnosis is typically confirmed by genetic testing, such as mutation analysis of the dystrophin gene, rather than relying solely on aldolase levels 1. However, in certain cases, such as immune-related myositis, aldolase levels may be used to support the diagnosis and guide treatment decisions 1.
From the Research
Muscle Damage and Muscular Dystrophy Diagnosis
- Obtaining an aldolase level can be useful in diagnosing or monitoring muscle damage or muscular dystrophy, particularly in cases where creatine kinase (CK) levels are within the normal range 2.
- Elevated serum aldolase with normal CK has been associated with various myopathies, including dermatomyositis, immune-mediated myopathy with perimysial pathology, and fasciitis with associated myopathy 3, 4.
- In patients with muscle discomfort or mild weakness and normal CK, measurement of serum aldolase can be useful in evaluating possible myopathies 3.
Enzyme Diagnosis in Muscular Dystrophies
- Serum enzyme activities, including aldolase, are important for diagnosing and monitoring muscular diseases, reflecting degeneration of muscular tissue 5.
- In Duchenne muscular dystrophy, serum enzyme activities show an increase during the first three years of life, a maximum between the age of 3 and 4, and an asymptotic decline thereafter 5.
- The course of different enzyme activities in Duchenne muscular dystrophy can be described by a mathematical formula, allowing for individual calculation of the constant c, which is correlated to the speed of disease progression 5.
Differentiating Skeletal Muscle from Liver Damage
- Gamma-glutamyl transferase (GGT) has been tested as a biomarker to distinguish skeletal muscle from liver damage, but it was found that GGT levels were not elevated in Duchenne muscular dystrophy patients, while creatine kinase levels were significantly elevated 6.
- This suggests that GGT may not be a reliable biomarker for differentiating skeletal muscle from liver damage in patients with muscle disorders 6.
Disease Spectrum of Myopathies with Elevated Aldolase
- A study investigated the disease spectrum of myopathies with isolated aldolase elevation and found that various types of myopathies were associated with this condition, including dermatomyositis, overlap myositis, and nonspecific myopathy 4.
- Perimysial pathology was found in 50% of patients with isolated aldolase elevation, and most patients had treatable myopathies 4.