American Board of Internal Medicine (ABIM) Certification Practice Exam

When might drug-induced Acute Interstitial Nephritis occur within a very short time frame after exposure?

1. Only if the patient has been previously exposed

2. Always within the first 24 hours

3. Only in patients with underlying kidney disease

4. Never occurs within one day

The correct answer is: Only if the patient has been previously exposed

Acute Interstitial Nephritis (AIN) can indeed occur shortly after drug exposure, especially in individuals who have been previously sensitized to a particular agent. This often involves an immune-mediated response to the drug that can lead to inflammation of the renal interstitium. When a patient has had prior exposure to a drug that they have developed a sensitivity to, they may experience an accelerated response, resulting in AIN manifesting within a short time frame, sometimes within days or even hours after re-exposure. While AIN can clinically present after multiple drug exposures, prior sensitization plays a significant role in the rapid development of symptoms following a subsequent exposure. In certain cases, the kidneys may react to the drug more quickly due to the existing memory of the immune system, explaining the rapid onset of the condition. The other options either suggest conditions or parameters that do not accurately reflect the nature of AIN or misrepresent how quickly this condition can arise. It is important to recognize that prior exposure can trigger a more immediate response compared to a patient without such sensitization.