A Case of Cardiogenic Shock Secondary to Complement-Mediated Myopericarditis From Influenza B Infection

Influenza B is a rare cause of myocarditis that is usually caused by histiocytic and mononuclear cellular infiltrates. We describe a 22-year-old female patient presenting with fulminant myopericarditis secondary to influenza B infection that deteriorated to cardiogenic shock. Endomyocardial biopsy results yielded myocardial necrosis through complement-mediated cellular injury without evidence of interstitial infiltrates. The rare cause of this patient's disease, along with the unique pathologic findings, are an important reminder of the diversity of potential findings in myocarditis.