A 13-YEAR-OLD GIRL WITH PROXIMAL WEAKNESS AND HYPERTROPHIC CARDIOMYOPATHY WITH DANON DISEASE

Abstract

Danon disease is caused by deficiency of lysosome-associated membrane protein-2 (LAMP-2). It is characterized clinically by cardiomyopathy, myopathy, and mental retardation in boys. Herein we report a 13-year-old female patient with Danon disease who presented with early-onset skeletal myopathy and cardiomyopathy. She had a de novo novel mutation in the LAMP2 gene, and her muscles showed many autophagic vacuoles with sarcolemmal features and complete absence of LAMP-2 expression. To the best of our knowledge, this girl is one of the earliest-onset manifesting carriers of Danon disease with typical muscle pathology.