THE ASSOCIATION The mission of The Myositis Association

is to find a cure for inflammatory and The Myositis Association (TMA) is a non-profit, voluntary health agency dedicated to improving related , while serving those the lives of people affected by myositis. Formed affected by these diseases. in 1993, TMA has grown from 16 patients, who

helped form the organization, to more than 6,000 Myositis members who have been served by TMA.

TMA is governed by a volunteer Board of Directors that includes patients, family members and interested professionals, bringing diverse strengths and perspectives to the organization.

Through member newsletters, publications, support groups, research and advocacy, TMA helps those who have myositis today and works to prevent any others from having to experience myositis in the future.

THE MYOSITIS ASSOCIATION 1233 20th Street, NW, Suite 402 • Washington, DC 20036 [email protected] • www.myositis.org 800.821.7356 THE MYOSITIS ASSOCIATION WHAT IS MYOSITIS? www.myositis.org

“Myositis” describes or swelling of INCLUSION-BODY MYOSITIS the muscle tissue. General muscle inflammation Dermatomyositis (DM) affects people of any age Inclusion-body myositis (IBM) is found in more can occur after exercising or taking certain med- or sex but is more common in women than men. men than women and is rarely seen in people less ication, or it can be from one of the chronic DM is the easiest type of myositis to diagnose than 50 years old. IBM progresses more slowly because it typically has a visible skin caused than the other types of myositis, as weakness inflammatory muscle disorders. Dermatomyositis by inflammation of blood vessels under the skin. happens gradually over months or years. Some (DM), (PM), inclusion-body The DM rash looks patchy and reddish or pur- of the first signs of IBM are falling, difficulty myositis (IBM), and juvenile forms of myositis ple, and is found on the , , standing from a seated position, and weakening and knuckles. Additional may occur on grip. Muscles most often affected are those at the (JM) are all inflammatory myopathies, or dis- the cheeks, nose, back, and upper chest. Some front of the thighs, hips, foot-elevators, fingers, eases where there is inflammation and loss of people also have hardened bumps under the skin, wrists, upper arms, shoulders, neck, and back. called calcinosis. Patients usually experience Many IBM patients notice shrinking, or atrophy, muscle. Depending on the type of myositis, the gradual and sometimes pain, in the arms and thighs as the muscles become first signs of myositis may include general tired- and they often report the rash well before the weaker. Trouble swallowing () is a ness, trouble standing from a seated position, dif- muscle weakness. Three sub-types of DM are common problem for IBM patients. Weakness of amyopathic DM, where the skin is affected but facial muscles is sometimes seen. ficulty climbing stairs, and weak grasping of muscles are not involved; cancer-associated DM, objects. where cancer and dermatomyositis are diagnosed JUVENILE MYOSITIS within two to three years of one another; and The underlying causes of DM, PM, IBM and overlap, where DM is associated with other Juvenile forms of myositis (JM) occur in chil- JM are not known, but some doctors believe autoimmune diseases. dren younger than 18 and affect more girls than there is an environmental exposure (perhaps to boys. Juvenile dermatomyositis (JDM) is the POLYMYOSITIS most common form, affecting an estimated 3,000 an or sunlight) that triggers the disease to 5,000 children in the United States. in someone who has certain specific but not yet Polymyositis (PM) is found more frequently in Polymyositis in children (JPM) occurs in adults than children. More women than men approximately 10% of children with JM. Signs fully defined genes or gene sequences that pre- have PM. Patients experience muscle weakness of JM include the characteristic skin rashes (i.e. dispose him or her. Inflammatory myopathies are gradually over weeks or months, typically begin- a visible, reddish-purple rash over the eyelids or classified as autoimmune diseases, meaning the ning with muscles closest to and within the trunk over joints), trouble climbing or lifting the head, of the body, such as neck, hip, back and shoulder weak voice (dysphonia), or problems swallowing body's , which normally fights muscles, and affecting both sides of the body (dysphagia). The muscles most often affected are and viruses, does not stop fighting equally. Some patients also have weakness in those closest to the center of the body – neck, once the infection or virus is gone. The immune their and fingers. PM patients generally stomach, upper arms, and legs. About half of the do not have skin rashes. Some PM patients have children with JM report pain in their muscles. system is misdirected and attacks the body’s own trouble swallowing (dysphagia), difficulty Some children have calcinosis (hardened lumps normal, healthy tissue. Inflammatory myopathies breathing (often associated with interstitial lung under the skin) or (when the mus- disease) and muscle pain. PM may be associated cle shortens and causes the joint to stay bent). are rare diseases and combined affect an estimat- with a malignancy or with other autoimmune dis- Children may have one or more other autoim- ed 50,000 people in the U.S. eases (overlap). mune diseases along with myositis (overlap myositis).