Danon Disease Diagnosed by Multimodal Imaging

Danon disease is a rare X-linked dominant disorder caused by loss-of-function mutations in lysosome-associated membrane protein-2 (LAMP2).

We report an 18-year-old male patient in which multimodal imaging revealed left ventricular hypertrophy, reduced myocardial perfusion, electrocardiographic evidence of pre-excitation, abnormal serologic parameters, and histopathologic abnormalities. Genetic testing identified a variant in LAMP2, confirming the diagnosis of Danon disease. Testing of his mother and 3 children also revealed the LAMP2 variant.

Patients with Danon disease primarily present with cardiac manifestations, including hypertrophic cardiomyopathy, arrhythmia, and heart failure.

Young men exhibiting myocardial hypertrophy, elevated plasma creatine kinase, pre-excitation on electrocardiography, and/or characteristic late gadolinium enhancement on cardiac magnetic resonance should be evaluated for Danon disease. Multimodal imaging (echocardiography, cardiac magnetic resonance) combined with genetic testing is key to accurate diagnosis. Family screening and genetic counseling are crucial given the X-linked dominant-inheritance pattern.