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About Myositis and Inclusion Body Myositis

Myositis is the medical term for inflammation of the muscle. In myositis, the body’s immune system mounts an attack on the fibers of the muscle. This causes muscle damage, pain and will result in progressive weakening of the muscle if the disease is not thwarted.

In some cases, myositis is a short-term problem that goes away after a few days or weeks. In other cases, it is part of a chronic long-term medical condition. Chronic forms of myositis can lead to muscle atrophy and severe disability. There are several types of chronic myositis, including Idiopathic Inflammatory Myopathies. In this rare group of muscle diseases, the cause of the muscle inflammation is unknown (idiopathic). There are three major types of myopathies: dermatomyositis, polymyositis and inclusion body myositis.

Inclusion Body Myositis

Inclusion Body Myositis (IBM) typically begins after age 50, and is characterized by gradual weakening of muscles throughout the body, including the wrists or fingers, development of dysphagia (difficulty in swallowing), and atrophy of forearms and thigh muscles. Unlike the other types of myositis, IBM occurs more often in men than women, and the disease does not respond to currently available drug therapy and the focus of current management is on palliation.  With the current limitations on patient management options, it is typical for IBM patients to require a wheelchair for mobility within 10 years