What are the implications of elevated Creatine Kinase (CK) levels?

From the Guidelines

Elevated creatine kinase (CK) levels indicate muscle damage and require immediate medical evaluation to determine the cause and prevent potential morbidity and mortality. The implications of elevated CK levels can be severe, and it is essential to identify the underlying cause to provide appropriate treatment. Common causes of elevated CK levels include intense exercise, muscle trauma, certain medications (like statins), and muscle disorders 1. If you have elevated CK levels, it is crucial to consult your doctor, who may recommend:

• Stopping strenuous exercise for 3-5 days before retesting
• Reviewing your medications
• Further testing based on your symptoms Persistent high levels may require referral to a specialist. Normal CK ranges are typically 22-198 units/L for women and 24-204 units/L for men, though these vary by laboratory 2. Mild elevations (up to 3 times normal) often resolve with rest, while higher levels may indicate more serious conditions, such as myositis, which can be severe and fatal 1. CK is an enzyme released when muscle cells are damaged, which is why monitoring these levels helps diagnose and track muscle-related conditions. Some key points to consider:
• Myositis is a rare but severe complication of immune checkpoint inhibitor therapy, and elevated CK levels can be an indicator of this condition 1
• Patients with myositis may present with weakness, primarily in the proximal extremities, and may require urgent treatment to avoid fatal complications 2
• Laboratory tests, such as autoantibody panels and EMG, may be useful in diagnosing myositis 2 It is essential to stay hydrated and avoid excessive muscle strain while awaiting medical guidance. In cases of severe myositis, treatment may involve high-dose corticosteroids, immunosuppressants, and other therapies, and it is crucial to seek medical attention immediately if you experience any symptoms of myositis, such as severe weakness or myalgia 1.

From the Research

Implications of Elevated Creatine Kinase (CK) Levels

Elevated serum CK levels can have various implications, including:

• Benign and temporary conditions, which are common in psychiatric in-patient practice 3
• Antipsychotic-induced rhabdomyolysis, a serious condition that requires careful monitoring and management 3
• Neuroleptic malignant syndrome, a life-threatening condition that requires prompt recognition and treatment 3
• Acute coronary syndrome, a condition that requires immediate medical attention 3
• Muscle damage or disease, such as myopathy or muscular dystrophy 4, 5
• Cardiotoxicity, as seen in a case report of aminophylline treatment 6

Clinical Significance

The clinical significance of elevated CK levels depends on the underlying cause, which can be:

• Prescription drugs, such as antipsychotics or aminophylline 3, 6
• Alcohol or physical trauma 3
• Cardiac etiology, such as acute coronary syndrome 3
• Neurological disorders, such as seizures or hypertrophic cardiomyopathy 5
• Macro-creatine kinase, a neglected cause of elevated CK 7

Diagnostic Approach

A diagnostic approach to elevated CK levels should include:

• A comprehensive patient history and physical examination 4
• Laboratory tests, such as nerve conduction studies and electromyography (EMG) 4
• Imaging studies, such as echocardiography or pulmonary perfusion scan 6
• Monitoring of CK levels and other biomarkers of cardiac injury 6