One of the rosacea mimics is seen below and is why rosacea is so confusing:
"Dermatomyositis (DM) is a connective-tissue disease related to polymyositis (PM) that is characterized by inflammation of the muscles and the skin." Wikipedia

Dermatomyositis - Image A.D.A.M.
Inflammation of the connective tissues (dermatomyositis) typically produces a reddish-purple (violaceous) rash. The rash is named after the tendency of plants to grow toward the sun (heliotropic) and is characteristic of dermatomyositis. Source

Dermatomyositis - Image medical-look.com
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