How does vesicoureteral reflux contribute to renal injury in children?

• A. Reflux allows ascending bacterial infection, increasing risk of pyelonephritis and renal scarring.
• B. It causes immune complex deposition in glomeruli.
• C. It increases diuresis leading to dehydration.
• D. It reduces bladder capacity causing obstruction.

Answer: (A)

Vesicoureteral reflux lets urine travel backward from the bladder into the ureters and kidneys. When bacteria are present in the bladder, this retrograde flow can carry them up to the upper urinary tract, increasing the risk of acute pyelonephritis. In the developing kidney, infection of the renal parenchyma triggers inflammation that often heals with scar tissue. Recurrent infections in childhood can thus lead to renal scarring, loss of nephrons, and potential long-term issues with kidney function and blood pressure. Immune complex deposition in glomeruli isn’t driven by reflux, and increased diuresis or bladder capacity obstruction don’t describe how reflux damages the kidneys.