Danon Disease Diagnosed by Multimodal Imaging: A Case Report

Danon disease is an X‐chromosome dominant disorder caused by variants in lysosomal‐associated membrane protein‐2 (LAMP‐2). Patients often present with cardiac lesions as their initial symptom, including hypertrophic cardiomyopathy, arrhythmia, and heart failure. We found a case of a 13‐year‐old male patient with multimodal imaging suggestive of left ventricular hypertrophy, decreased left ventricular myocardial perfusion, electrocardiographic abnormalities, and abnormal serologic parameters. Genetic testing revealed a variant located in the LAMP2 gene, leading to the diagnosis of Danon disease. Danon disease is a multisystem disorder with a predominance of cardiac lesions, and it should be considered when imaging suggests myocardial hypertrophy or dilatation.