Association between monoclonal gammopathy and dilated cardiomyopathy: A case report in an adolescent

We report the case of a 14-year-old adolescent presenting a novel association between monoclonal gammopathy and dilated cardiomyopathy (DCM). This clinical case, remarkable for its rarity, highlights a potential pathological link between these two entities. The patient initially presented with signs indicative of progressive heart failure, including significant fatigue, exertional dyspnea, and peripheral edema. Cardiac investigations confirmed the diagnosis of DCM with a significantly reduced left ventricular ejection fraction, reflecting severe systolic dysfunction. Simultaneously, biological analyses revealed the presence of a monoclonal spike on serum protein electrophoresis, confirmed by immunofixation as a specific type of immunoglobulin (Ig). The origin of this monoclonal gammopathy remained undetermined despite extensive investigations before the patient’s death during her short hospital stay.