Inclusion body myositis
Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.
Age of Onset
Autosomal dominant ?A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease
Autosomal recessive ?Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype
X-linked dominant ?X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.
X-linked recessive ?Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder
Mitochondrial or multigenic ?Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.
Multigenic or multifactor ?Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.
Other Names (AKA)
IBM; Inflammatory myopathy; Sporadic inclusion body myositis
Musculoskeletal Diseases; Nervous System Diseases
Inclusion body myositis (IBM) is a progressive muscle disorder characterized by muscle inflammation, weakness, and atrophy (wasting). It is a type of inflammatory myopathy. IBM develops in adulthood, usually after age 50. The symptoms and rate of progression vary from person to person. The most common symptoms include progressive weakness of the legs, arms, fingers, and wrists. Some people also have weakness of the facial muscles (especially muscles controlling eye closure), or difficulty swallowing (
Most people with IBM progress to disability over a period of years. In general, the older a person is when IBM begins, the more rapid the progression of the condition. Most people need assistance with basic daily activities within 15 years, and some people will need to use a wheelchair. Lifespan is thought to be normal, but severe complications (e.g. aspiration pneumonia) can lead to loss of life.
The underlying cause of IBM is poorly understood and likely involves the interaction of genetic, immune-related, and
There is currently no cure for IBM. The primary goal of management is to optimize muscle strength and function. Management may include exercise, fall prevention,
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.
|Medical Terms||Other Names||
|80%-99% of people have these symptoms|
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|Elevated serum creatine kinase||
Elevated blood creatine phosphokinase
Elevated circulating creatine phosphokinase
Elevated creatine kinase
Elevated serum CPK
Elevated serum creatine phosphokinase
High serum creatine kinase
Increased creatine kinase
Increased creatine phosphokinase
Increased serum CK
Increased serum creatine kinase
Increased serum creatine phosphokinase
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|Quadriceps muscle weakness||
|Ragged-red muscle fibers||0003200|
|Skeletal muscle atrophy||
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|30%-79% of people have these symptoms|
|Feeding difficulties in infancy||0008872|
|Reduced tendon reflexes||0001315|
|5%-29% of people have these symptoms|
[ more ]
|Percent of people who have these symptoms is not available through HPO|
|Distal muscle weakness||
Weakness of outermost muscles
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Decreased reflex response
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|Proximal muscle weakness||
Weakness in muscles of upper arms and upper legs
Signs and symptoms worsen slowly with time
No previous family history
Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.
Conditions with similar signs and symptoms from Orphanet
Differential diagnosis may include polymyositis (see this term) and, in early stages of the disease, arthritis or any motor neuron disease (see this term).
Visit the Orphanet disease page for more information.
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.
American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM)
2621 Superior Drive NW
Rochester, MN 55901
American Autoimmune Related Diseases Association (AARDA)
19176 Hall Road, Suite 130
Clinton Township, MI 48038
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.
- MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
- Genetics Home Reference (GHR) contains information on Inclusion body myositis. This website is maintained by the National Library of Medicine.
- The National Institute of Neurological Disorders and Stroke (NINDS) collects and disseminates research information related to neurological disorders. Click on the link to view information on this topic.
- The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.
- Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
- 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 Inclusion body myositis. Click on the link to view a sample search on this topic.
- Miller ML, Lloyd TE. Clinical manifestations and diagnosis of inclusion body myositis. UpToDate. Waltham, MA: UpToDate; Match 7, 2016; https://www.uptodate.com/contents/clinical-manifestations-and-diagnosis-of-inclusion-body-myositis.
- Sporadic Inclusion Body Myositis. National Organization for Rare Disorders (NORD). 2016; https://rarediseases.org/rare-diseases/sporadic-inclusion-body-myositis/.
- Lloyd TE. Management of inclusion body myositis. UpToDate. Waltham, MA: UpToDate; May 18, 2017; https://www.uptodate.com/contents/management-of-inclusion-body-myositis.