National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Idiopathic inflammatory myopathy



Other Names:
Idiopathic inflammatory myopathy, familial; IIM; Myositis; Idiopathic inflammatory myopathy, familial; IIM; Myositis; Idiopathic inflammatory myositis; IMM See More
Subtypes:

Idiopathic inflammatory myopathy refers to a group of conditions that affect the skeletal muscles (muscles used for movement). Although the condition can be diagnosed at any age, idiopathic inflammatory myopathy most commonly occurs in adults between ages 40 and 60 years or in children between ages 5 and 15 years. Signs and symptoms of the condition include muscle weakness, joint pain and fatigue. There are several forms of idiopathic inflammatory myopathy, including polymyositis, dermatomyositis, and sporadic inclusion body myositis, which are each associated with unique features.[1][2][3] As the name suggests, the cause of the condition is currently unknown (idiopathic). However, researchers suspect that it may occur due to a combination of genetic and environmental factors.[1] Treatment is supportive and based on the signs and symptoms present in each person.[3][2]
Last updated: 2/17/2016

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Showing of 3 |
Medical Terms Other Names
Learn More:
HPO ID
Percent of people who have these symptoms is not available through HPO
Autosomal dominant inheritance 0000006
Myositis
Muscle inflammation
0100614
Proximal muscle weakness
Weakness in muscles of upper arms and upper legs
0003701
Showing of 3 |
Last updated: 7/1/2020

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources


Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • The Centers for Mendelian Genomics program is working to discover the causes of rare genetic disorders. For more information about applying to the research study, please visit their website.
  • ClinicalTrials.gov lists trials that are related to Idiopathic inflammatory myopathy. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease


These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

In-Depth Information

  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Idiopathic inflammatory myopathy. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know.


  1. Idiopathic inflammatory myopathy. Genetics Home Reference. February 2011; http://ghr.nlm.nih.gov/condition/idiopathic-inflammatory-myopathy.
  2. Facts about Inflammatory Myopathies. Muscular Dystrophy Association. 2009; https://www.mda.org/sites/default/files/publications/Facts_Inflamm_Myopathies_P-199.pdf.
  3. Inflammatory Myopathies Fact Sheet. National Institute of Neurological Disorders and Stroke. July 2015; http://www.ninds.nih.gov/disorders/inflammatory_myopathies/detail_inflammatory_myopathies.htm.