In renal disease, how does the LD isoenzyme pattern compare to normal?

In renal disease, how does the LD isoenzyme pattern compare to normal?

• A. Higher absolute values of LD isoenzymes
• B. Lower LD total
• C. Earlier rise of LD1
• D. No change in pattern

Answer: (A)

Lactate dehydrogenase has several isoenzymes that circulate in the blood when tissues are damaged. In renal disease, injury to renal tissue releases LDH into the circulation, so the total LD activity rises and the absolute amounts of the individual isoenzymes increase. The pattern isn’t about a single isoenzyme appearing or changing dramatically in its proportion; it’s about there being more of each isoenzyme overall. So, the best description is higher absolute values of LD isoenzymes. The other ideas imply a decrease in LD, a selective early rise of a specific isoenzyme, or no change, which doesn’t fit the way LDH behaves in tissue injury.

Lactate dehydrogenase has several isoenzymes that circulate in the blood when tissues are damaged. In renal disease, injury to renal tissue releases LDH into the circulation, so the total LD activity rises and the absolute amounts of the individual isoenzymes increase. The pattern isn’t about a single isoenzyme appearing or changing dramatically in its proportion; it’s about there being more of each isoenzyme overall. So, the best description is higher absolute values of LD isoenzymes. The other ideas imply a decrease in LD, a selective early rise of a specific isoenzyme, or no change, which doesn’t fit the way LDH behaves in tissue injury.