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.
Polymyositis (PM)(inflammation of many muscles) is a type of chronic inflammation of the muscles (inflammatory myopathy) related to dermatomyositis and inclusion body myositis.olymyositis is an inflammatory myopathy mediated by cytotoxic T cells with an as yet unknown autoantigen, while dermatomyositis is a humorally mediated angiopathy resulting in myositis and a typical dermatitis. The cause of polymyositis is unknown and may involve viruses and autoimmune factors.