An HIV-positive patient with chest discomfort, a pericardial friction rub, diffuse ST elevations, and normal troponin levels most likely has which diagnosis?

• A. Acute myocardial infarction
• B. Acute pericarditis
• C. Acute bacterial endocarditis
• D. Acute costochondritis

Answer: (B)

This scenario points to pericardial inflammation rather than a heart attack. Pericarditis typically presents with chest pain and a pericardial friction rub, and the ECG shows diffuse, usually concave-upward ST-segment elevations across many leads, often with PR-segment depression. The troponin can remain normal because the myocardium itself isn’t infarcted, though it may be modestly elevated if there’s concurrent myocarditis (myopericarditis). In an HIV-positive patient, pericardial disease is common due to infectious causes like TB or viral infections, which fits the context.

Acute myocardial infarction would usually show chest pain with ST elevations localized to a vascular territory and elevated troponin. Acute costochondritis causes chest wall pain without a pericardial friction rub or the characteristic diffuse ST changes. Acute bacterial endocarditis would more likely present with fever, a new heart murmur, and signs of emboli or sepsis, not a friction rub with diffuse ST elevations.

So the combination of chest pain, a pericardial friction rub, diffuse ST elevations, and normal troponin best fits acute pericarditis.