Prescribing Safety Assessment (PSA) Practice Exam

Which of the following is NOT a recognized cause of post-renal AKI?

1. Stones

2. Tumors

3. Nephrotoxic agents

4. Benign Prostate Hyperplasia

The correct answer is: Nephrotoxic agents

Post-renal acute kidney injury (AKI) occurs due to obstruction in the urinary tract, which can impede the flow of urine and lead to kidney damage. Among the causes listed, nephrotoxic agents are recognized for causing damage to the kidneys, but they primarily contribute to pre-renal or intrinsic renal AKI rather than post-renal AKI. Nephrotoxic agents can damage kidney tubules or affect glomerular function directly, but they do not create an obstruction in the urinary tract. In contrast, stones, tumors, and benign prostatic hyperplasia are all conditions that can lead to obstruction in the urinary path, thereby causing post-renal AKI. For example, kidney stones can block the ureters, tumors can compress the urinary tract, and benign prostatic hyperplasia can obstruct the urethra. These obstructions disrupt normal urine flow and can result in increased pressure in the renal collecting system, ultimately leading to kidney injury. Thus, the option identifying nephrotoxic agents is correct because they do not represent a mechanism for obstruction and are therefore not a recognized cause of post-renal AKI. Understanding these distinctions is crucial for diagnosing and managing acute kidney injury effectively.