From the Guidelines
Aldolase is a diagnostic marker for muscle and liver damage, and its levels should be interpreted in the context of clinical presentation and other laboratory tests, such as creatine kinase (CK) and liver enzymes (ALT, AST) 1.
Clinical Significance of Aldolase
Aldolase is an enzyme that catalyzes the reversible conversion of fructose-1,6-bisphosphate to glyceraldehyde-3-phosphate and dihydroxyacetone phosphate during glycolysis. Elevated aldolase levels in blood typically indicate tissue damage, particularly in skeletal muscle, cardiac muscle, or liver cells.
- Normal serum aldolase levels generally range from 1.0 to 7.5 units per liter, though reference ranges may vary between laboratories.
- The test is most useful when evaluating patients with suspected muscle disorders like muscular dystrophy, polymyositis, or dermatomyositis, where levels can rise to 5-10 times normal.
- It's also elevated in conditions like hepatitis, liver cancer, heart attacks, and severe trauma.
Limitations and Alternative Markers
While once commonly used, aldolase testing has been largely replaced by more specific markers like creatine kinase (CK) for muscle damage and liver enzymes (ALT, AST) for hepatic injury.
- However, it remains valuable in certain clinical scenarios, particularly when monitoring disease progression in established muscle disorders or when other enzyme tests yield inconclusive results.
- For example, in patients with nonalcoholic steatohepatitis (NASH), aldolase levels may be elevated due to muscle injury, which can be mistaken for acute drug-induced liver injury (DILI) 1.
- Testing for blood levels of creatine phosphokinase (CK), aldolase, or other muscle-related enzymes can confirm the nonhepatic origin of this event.
Clinical Guidelines and Recommendations
In clinical practice, aldolase levels should be interpreted in the context of clinical presentation, medical history, and other laboratory tests, such as CK and liver enzymes 1.
- For patients with suspected myositis, the American Society of Clinical Oncology (ASCO) recommends monitoring aldolase levels, along with CK and other laboratory tests, to assess disease activity and response to treatment 1.
- In patients with NASH, a comprehensive evaluation, including laboratory tests and medical history, is necessary to distinguish between DILI and other causes of liver injury, such as gallstone disease or muscle injury 1.
From the Research
Aldolase Overview
- Aldolase (EC 4.1.2.13) plays a crucial role in glucose metabolism, with a molecular weight of 160 kDa and three isozymes: aldolase A, B, and C 2.
- The enzyme is present in all cells, with high quantities found in muscles, liver, and brain 2.
Clinical Significance
- Elevated serum aldolase levels are associated with myotonic muscular disease, such as progressive muscular dystrophy and polymyositis, with aldolase A isozyme being elevated 2.
- Aldolase activity, particularly B isozyme, rises in acute hepatitis, but is slightly elevated in cirrhosis, chronic hepatitis, and obstructive jaundice 2.
- Aldolase becomes elevated in serum with malignant tumors, with isozyme A being predominant in serum 2.
- Eosinophilic fasciitis (EF) diagnosis and management can utilize elevated aldolase levels, which are more likely to be abnormal than peripheral eosinophilia, hypergammaglobulinemia, and ESR 3.
Deficiency and Related Conditions
- Aldolase A deficiency is a rare autosomal recessive disorder causing hemolytic anemia and/or recurrent episodes of rhabdomyolysis, usually precipitated by fever 4.
- Duchenne muscular dystrophy (DMD) treatment with corticosteroids can stabilize muscle strength for a period, with prednisone/prednisolone and deflazacort being the main steroids used 5.
- Amyotrophic Lateral Sclerosis (ALS) treatment can benefit from physical and occupational therapy intervention, which can help maximize mobility and comfort 6.