The main features of Danon disease in boys are heart disease (cardiomyopathy), skeletal muscle weakness, and mild intellectual problems. Heart problems are the main cause of symptoms and carry the greatest risks of hospitalization and early death. Muscle problems are usually mild and boys rarely require walkers or wheelchairs. Females with Danon disease develop symptoms, on average, about 13 years later than boys, although some girls with severe Danon disease in childhood have been reported. Females rarely have skeletal muscle or intellectual disability problems.
LAMP2