From the Guidelines
A high CPK level indicates muscle damage or injury, and immediate medical attention is necessary to prevent complications such as rhabdomyolysis and acute kidney injury, as evidenced by a study published in 2021 1. When CPK levels exceed five times the normal range, it can be a sign of rhabdomyolysis, which may lead to acute kidney injury, as seen in patients with crush syndrome following an earthquake 1. Some key points to consider:
- Rest the affected muscles and avoid strenuous exercise until cleared by your doctor.
- Stay well-hydrated by drinking plenty of water to help flush enzymes from your bloodstream.
- Your doctor may recommend over-the-counter pain relievers like ibuprofen (400-600mg every 6-8 hours) or acetaminophen (500-1000mg every 6 hours) for associated muscle pain.
- The underlying cause of your high CPK needs to be identified, as it could result from intense exercise, muscle trauma, certain medications (particularly statins), inflammatory muscle diseases, or even heart attacks.
- CPK is an enzyme found primarily in your muscles, heart, and brain, and when these tissues are damaged, CPK leaks into your bloodstream, causing elevated levels.
- Normal CPK levels typically range from 30-200 units/L, though this varies by laboratory and gender. It is essential to note that a study published in 2019 1 discussed the importance of considering other causes of elevated liver enzymes, such as gallstone disease, hepatic tumor, or drug-induced liver injury, in patients with nonalcoholic steatohepatitis (NASH). However, this is not directly relevant to the management of high CPK levels. In patients with severe limb trauma, raising CPK levels above five times normal is a sign of rhabdomyolysis, and immediate medical attention is necessary to prevent complications, as recommended by the 2021 guidelines for the acute care of severe limb trauma patients 1.
From the Research
High CPK Levels
- High CPK levels can be associated with various conditions, including muscle damage and myocardial infarction 2, 3, 4.
- Elevated CPK levels can be caused by statin-associated muscle symptoms (SAMS), with simvastatin use, BMI, and CK-MB being independent markers of SAMS 2.
- The total CPK/MB/CPK ratio can be used to discriminate between myocardial infarction and muscular necrosis, with a ratio of less than 5% indicating muscular necrosis 3.
- Elevated serum MB CPK activity is a highly specific and sensitive criterion of myocardial injury 4.
- High CPK levels can also be found in febrile diseases, with 28% of febrile patients having elevated CPK levels, but this is not necessarily indicative of a specific etiology 5.
Diagnostic Markers
- Troponin-I is a sensitive marker for myocardial infarction, with elevated levels indicating myocardial damage 3, 6.
- CPK-MB mass and myoglobin can be used to diagnose myocardial infarction, with optimal sensitivity and specificity 6 hours after the onset of chest pain 6.
- Cardiac troponin T is a useful marker for prognostic stratification, with a single determination 6 hours after the onset of chest pain being the most sensitive and specific marker for new ischemic recurrences 6.