Which enzyme is most elevated in Duchenne muscular dystrophy?

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Multiple Choice

Which enzyme is most elevated in Duchenne muscular dystrophy?

When muscle fibers are constantly damaged, as in Duchenne muscular dystrophy, their membranes leak enzymes into the bloodstream. Creatine kinase, especially the CK-MM isoform that sits abundantly in skeletal muscle, is released in large amounts when these fibers break down. Because CK is highly concentrated in muscle and is released quickly with muscle injury, its levels rise very markedly in DMD and serve as a sensitive indicator of ongoing muscle damage. ALT is mainly a liver enzyme, though it can rise with muscle injury, it’s not as sensitive or specific for skeletal muscle damage. AST is present in liver, heart, and muscle but tends to be less specific and less dramatically elevated for muscle injury. LDH is a general marker released from many tissues, so it doesn’t pinpoint skeletal muscle damage as clearly. Thus, CK stands out as the most elevated and a key clue pointing to muscle-specific injury in this condition.

When muscle fibers are constantly damaged, as in Duchenne muscular dystrophy, their membranes leak enzymes into the bloodstream. Creatine kinase, especially the CK-MM isoform that sits abundantly in skeletal muscle, is released in large amounts when these fibers break down. Because CK is highly concentrated in muscle and is released quickly with muscle injury, its levels rise very markedly in DMD and serve as a sensitive indicator of ongoing muscle damage.

ALT is mainly a liver enzyme, though it can rise with muscle injury, it’s not as sensitive or specific for skeletal muscle damage. AST is present in liver, heart, and muscle but tends to be less specific and less dramatically elevated for muscle injury. LDH is a general marker released from many tissues, so it doesn’t pinpoint skeletal muscle damage as clearly. Thus, CK stands out as the most elevated and a key clue pointing to muscle-specific injury in this condition.

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