True about Dermatomyositis is?

Ans. is 'b' i.e., Bimodal age distribution * Although it can occur at any age; there is a bimodal distribution with peaks between age 10 & 15 years in children and between 45 & 60 years in adults.Important factors associated with dermatomyositis* It is the commonest type of inflammatory myopathy.* More common in females.* Associated with HLA types B8, B14 & DR3. Juvenile DM is associated with HLA DR3. Production anti-Jo-1 antibodies is strongly associated with HLA DR3.* DM is believed to be a microangiopathy affecting skin and muscles..* Other important factors associated with the causation of DM are drugs (Hydroxyurea, D-penicillamine, NSAIDs, phenytoin), silicone breast implants & bovine collagen implants.* Skin manifestation are often non-specific initially and commonly precede the onset of myositis by at least several months. They are precipitated by UV light.