Onion-induced anaphylactic shock rapidly evolving to allergic right ventricular myocardial infarction and subsequent cardiogenic shock

The type II variant of Kounis syndrome is defined as a rare allergic myocardial angina or infarction event in patients with preexisting quiescent coronary artery disease. Various causative factors have been implicated in the etiology of Kounis syndrome. However, reports highlighting the importance of recognizing a decreased preload caused by allergic right ventricular (RV) myocardial infarction and subsequent cardiogenic shock from ongoing anaphylactic shock are rare. Here we report the case of a 54-year-old male who initially presented with anaphylactic shock after ingesting onions. His condition silently progressed to RV infarction and cardiogenic shock within 2 hours of symptom onset. Under such instances, it is crucial to promptly identify RV infarction and cardiogenic shock by repeatedly performing electrocardiography at frequent intervals.