What is JM? Juvenile Myositis (JM), including Juvenile
Dermatomyositis (JDM), Amyopathic Dermatomyositis (AMD) and
Juvenile Polymyositis (JPM), is an autoimmune disease affecting
approximately 5,000 children in the United States. Weak muscles
and skin rash are the primary symptoms of JDM, while muscle
weakness without a rash is the primary symptom of JPM. Children
afflicted with AMD, on the other hand, experience the skin rash
without the weakened muscles. Even within these three
designations, JM affects every child differently. Some children
experience a mild form of the disease, while others follow a
more severe and potentially more debilitating course. Some of
the more onerous secondary symptoms are calcinosis, vasculitic
ulcers and contractures. Incidence of JM JM is a rare disease
and its exact incidence is unknown. Estimates from various
studies suggest that between 1 and 5 children per million will
develop this disease each year. Approximately 1,000 new cases of
JM are diagnosed in the United States ev