Which characteristic most strongly indicates Dressler syndrome rather than an acute myocardial infarction?

• A. Dyspnea
• B. Fever and leukocytosis
• C. ST elevation in the anterior leads
• D. Tachycardia

Answer: (B)

Dressler syndrome is an autoimmune inflammatory reaction of the pericardium that occurs weeks after a myocardial infarction. The hallmark is a systemic inflammatory response, so fever and leukocytosis are the most telling signs distinguishing it from an acute MI, where the presentation centers on ischemia and myocardial injury rather than a generalized inflammatory process. Fever reflects the inflammatory state, and leukocytosis accompanies this response, making them much more specific to Dressler than the other findings.

Dyspnea and tachycardia can appear in both conditions, so they’re less discriminating. ST elevations can occur in MI and, in Dressler, are often less localized (pericarditis may cause diffuse ST changes) but fever and leukocytosis specifically flag the inflammatory etiology rather than acute ischemia.