Which renal function indicator increases with renal failure and urinary obstruction?

Which renal function indicator increases with renal failure and urinary obstruction?

• A. Creatinine
• B. Bile
• C. ALT
• D. Albumin

Answer: (A)

The main idea is that serum creatinine rises when kidney filtration declines, which happens in renal failure and in urinary obstruction. Creatinine is a waste product produced at a fairly constant rate from muscle metabolism and is normally cleared by the kidneys through filtration. When the glomerular filtration rate decreases, such as with kidney failure or when an obstruction impairs urine flow and backpressure reduces filtration, creatinine accumulates in the blood. That makes creatinine a sensitive and specific indicator of reduced renal function and obstructive effects. The other substances listed are not renal function indicators in the same way. Bile and ALT are related to liver function, not kidney filtration, and albumin is a liver-produced protein (though it can be affected by various conditions, it doesn’t directly reflect acute changes in renal clearance). While BUN can also rise with kidney impairment, creatinine is more specifically tied to GFR and obstruction, which is why it’s the best choice here.

The main idea is that serum creatinine rises when kidney filtration declines, which happens in renal failure and in urinary obstruction. Creatinine is a waste product produced at a fairly constant rate from muscle metabolism and is normally cleared by the kidneys through filtration. When the glomerular filtration rate decreases, such as with kidney failure or when an obstruction impairs urine flow and backpressure reduces filtration, creatinine accumulates in the blood. That makes creatinine a sensitive and specific indicator of reduced renal function and obstructive effects.

The other substances listed are not renal function indicators in the same way. Bile and ALT are related to liver function, not kidney filtration, and albumin is a liver-produced protein (though it can be affected by various conditions, it doesn’t directly reflect acute changes in renal clearance). While BUN can also rise with kidney impairment, creatinine is more specifically tied to GFR and obstruction, which is why it’s the best choice here.