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Myositis is a rare, chronic, autoimmune muscle disease without a cure

Learn more about Myositis and how MSU is helping patients and caregivers

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Types of Myositis
Myositis: The Basics

What is Myositis?

Myositis is a term meaning inflammation in the muscles. Our focus is on the Idiopathic Inflammatory Myopathies of which there are several types, and are all classified as rare diseases. Idiopathic means the cause is unknown.

Polymyositis causes muscle weakness around the middle of the body and affects both sides of the body. Dermatomyositis causes muscle weakness as well as skin rashes. Juvenile Dermatomyositis differs from the adult form because of the coexistence of vasculitis (inflammation of blood vessels). Inclusion body myositis mainly affects older individuals. As muscle weakness becomes severe, it is accompanied by muscle wasting and diminished deep-tendon reflexes. Unlike Polymyositis and Dermatomyositis, the muscle weakness is often not symmetric and may be prominent in the smaller muscles of the forearms and calves.

Myositis resources and ways to get involved

Below are some important Myositis resources we have put together to help you educate yourself, become involved, and to locate needed resources.

We care about our members and site visitors and hope to offer you the most complete, easy-to-read information we can.

Our Programs and Services

Check out the programs and services we offer our Members such as financial assistance, letter writing review, advocacy, and online support programs.

View Programs and Services

Educate yourself

Learn about the different types and subtypes of Myositis, as well as how to diagnose and treat them. Learn about complications and overlap syndromes. This is for “Simply Put” series.

Learn about Myositis

Get Invovled

We are all in this together! So, why not get involved today. We offer many opportunities such as volunteering, be an admin for our support groups, join our board and more.

Find ways you can help

Join our online Myositis Network

Once you register as a member, we automatically create your profile in the MSU Myositis Network, a social network dedicated to only Myositis. Learn more and start using it today.

Learn how to use our Myositis Network



Myositis Resources

Myositis resources to help you find support, help, and assistance. We have compiled a ton of helpful information just for you.

Myositis Resources

Caregiver Resources

Myositis Caregivers, you deserve all of the support you can find. We have compiled a listing of resources that will help you find what you need.

Caregiver resources

Disability Resources

Myositis is often disabling. Therefore, we have put together an extensive list of resources patients need if they become disabled.

View Disability Resources

Myositis Support Groups

Living with Myositis is hard and you need support. We offer several support options including FB Support Groups and our website Myositis Network.

Find Myositis Support

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© Myositis Support and Understanding Association, Inc. 2010-2017. All Rights Reserved. MSU is a 501(c)(3) nonprofit organization.

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Hi, this may be interesting to you: Myositis Support and Understanding! The link is included below: --- Myositis Support and Understanding is a 501(c)3 nonprofit organization.