Some of these additional tests may include a WBC differential, a blood smear review, or in severe conditions, a bone marrow examination. A differential may indicate which type of WBC is low or high while a blood smear and/or bone marrow biopsy can reveal the presence of abnormal and/or immature WBCs. ^ Back to top.
The most common types are dermatomyositis, polymyositis, necrotising autoimmune myopathy and sporadic inclusion body myositis (IBM). Although dermatomyositis affects the skin and muscles, it may also affect other parts of the body such as joints, oesophagus, lungs and heart.
Myositis is a term meaning inflammation in the muscles. There are several types of myositis, the most common being polymyositis and dermatomyositis. Polymyositis causes muscle weakness around the middle of the body and affects both sides of the body. Dermatomyositis causes muscle weakness as well as a skin rash. Juvenile dermatomyositis differs from the adult form because of the coexistence of vasculitis (inflammation of blood vessels). Inclusion body myositis mainly affects older individuals.