AKI with hydronephrosis on ultrasound is most likely due to obstruction and may be relieved by which intervention?

• A. Bladder catheterization
• B. High-volume IV fluids
• C. Antibiotics
• D. Dialysis

Answer: (A)

The key idea is that hydronephrosis on ultrasound signals obstruction causing post-renal AKI. When urine flow is blocked, pressure backs up into the kidneys, impairing glomerular filtration. Relieving the blockage promptly can restore urine drainage and allow renal function to recover.

Bladder catheterization directly decompresses the bladder, reducing the outlet pressure and back-pressure on the kidneys. This quick intervention addresses the obstruction, which is the root cause of the AKI in this scenario, making it the most effective initial treatment.

High-volume IV fluids won’t fix an obstruction and may worsen issues if the kidneys aren’t able to drain urine. Antibiotics treat infection, not the obstruction. Dialysis is a supportive measure for severe, uncompensated kidney failure or specific metabolic derangements and doesn’t resolve the underlying obstruction.