Which lab value is markedly elevated in rhabdomyolysis?

Which lab value is markedly elevated in rhabdomyolysis?

• A. Creatinine kinase
• B. AST
• C. ALT
• D. Lactate dehydrogenase

Answer: (A)

In rhabdomyolysis, drastic muscle cell injury dumps intracellular contents into the bloodstream, and the enzyme most released from damaged skeletal muscle is creatine kinase. CK is highly concentrated in muscle (CK-MM), so when muscle is injured, CK rises far more dramatically than other enzymes. This makes CK the most sensitive and specific marker for the extent of muscle breakdown and it’s the primary lab value used to diagnose and monitor rhabdomyolysis. CK levels typically begin to rise within hours of injury and can peak within 24–72 hours, reaching very high numbers. In contrast, while AST and ALT can be elevated due to muscle injury, they are less specific because they’re also abundant in the liver. LDH is even more non-specific and can rise with a variety of tissue injuries. So the markedly elevated value in rhabdomyolysis is CK.

In rhabdomyolysis, drastic muscle cell injury dumps intracellular contents into the bloodstream, and the enzyme most released from damaged skeletal muscle is creatine kinase. CK is highly concentrated in muscle (CK-MM), so when muscle is injured, CK rises far more dramatically than other enzymes. This makes CK the most sensitive and specific marker for the extent of muscle breakdown and it’s the primary lab value used to diagnose and monitor rhabdomyolysis. CK levels typically begin to rise within hours of injury and can peak within 24–72 hours, reaching very high numbers.

In contrast, while AST and ALT can be elevated due to muscle injury, they are less specific because they’re also abundant in the liver. LDH is even more non-specific and can rise with a variety of tissue injuries. So the markedly elevated value in rhabdomyolysis is CK.