Myocarditis related to drug hypersensitivity

Hypersensitivity myocarditis is an inflammatory disease of the myocardium usually related to a drug allergy. The clinical manifestations may be nonspecific, and the diagnosis is seldom suspected or established during life. We report a case that demonstrates both typical and atypical features of this disease and review the clinicopathologic correlations. This case illustrates the potential occurrence of both electrical conduction block and ventricular tachyarrhythmias, either of which may account for the mechanism of sudden death in these patients. When cardiac symptoms or electrocardiographic abnormalities (or both) occur in a setting consistent with drug allergy, hypersensitivity myocarditis should be considered. Treatment consists of discontinuation of use of the drug responsible for the reaction and, possibly, administration of corticosteroids and immunosuppressive therapy.