Which symptom is common to both acute and chronic renal failure?

• A. Increased urine output
• B. Decreased urine output
• C. No protein in urine
• D. Normal blood pressure

Answer: (B)

The main idea here is that reduced urine production, or oliguria, is a common feature of both acute kidney injury and chronic kidney disease. When the kidneys’ filtering capacity drops, less urine is formed. In acute kidney injury, a sudden injury or loss of blood flow to the kidneys often causes a rapid fall in urine production. In chronic kidney disease, progressive loss of functioning nephrons lowers overall filtration, and urine output can diminish as kidney function declines. This makes decreased urine output a shared sign, whereas increased urine output isn’t typical of renal failure, and protein in the urine or normal blood pressure aren’t reliable indicators that apply to both conditions in the same way.