Decreased creatinine indicates which finding?

Decreased creatinine indicates which finding?

• A. Dehydration
• B. Starvation
• C. Reduced muscle mass
• D. Increased BUN

Answer: (C)

Creatinine on its own reflects how much muscle mass there is, because it is produced from muscle metabolism at a rate proportional to total muscle. It is cleared by the kidneys, so stable kidney function makes serum creatinine a reasonable proxy for production. When muscle mass decreases, production drops and serum creatinine falls. That’s why a decreased creatinine level points to reduced muscle mass. Dehydration usually elevates creatinine by reducing kidney perfusion and concentrating waste, and while starvation can be associated with lower creatinine through diminished muscle, the direct and most informative link is reduced muscle mass. Increased BUN relates to protein metabolism and hydration status, not the decrease in creatinine.

Creatinine on its own reflects how much muscle mass there is, because it is produced from muscle metabolism at a rate proportional to total muscle. It is cleared by the kidneys, so stable kidney function makes serum creatinine a reasonable proxy for production. When muscle mass decreases, production drops and serum creatinine falls. That’s why a decreased creatinine level points to reduced muscle mass. Dehydration usually elevates creatinine by reducing kidney perfusion and concentrating waste, and while starvation can be associated with lower creatinine through diminished muscle, the direct and most informative link is reduced muscle mass. Increased BUN relates to protein metabolism and hydration status, not the decrease in creatinine.