What mechanism of action likely causes acute kidney injury in patients taking NSAIDs?

The correct answer, which identifies the mechanism of action likely causing acute kidney injury in patients taking NSAIDs, is the inhibition of prostaglandins. NSAIDs work by blocking the cyclooxygenase (COX) enzymes, which are crucial for the synthesis of prostaglandins. Prostaglandins play several important roles in the kidneys, including the regulation of renal blood flow and the maintenance of glomerular filtration rate (GFR).

When NSAIDs inhibit prostaglandin production, this can lead to a reduction in renal blood flow, particularly in situations where the kidneys are already under stress, such as dehydration or heart failure. The decreased prostaglandin levels impair the vasodilatory response in the afferent arterioles of the glomeruli, ultimately leading to decreased glomerular perfusion and a risk of acute kidney injury.

Understanding this mechanism is crucial for managing patients on NSAIDs, especially those who may be more susceptible to renal issues, such as the elderly or those with pre-existing kidney conditions.