Acute disseminated encephalomyelitis
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)
Nervous System Diseases
Acute disseminated encephalomyelitis (ADEM) is a neurological condition characterized by a brief but intense attack of inflammation in the brain and spinal cord. This may lead to damage of the layer of insulation around the nerves (
ADEM can be misdiagnosed as a severe first attack of multiple sclerosis (MS), since some of the symptoms of the two disorders are similar. However, ADEM usually has symptoms of encephalitis (such as fever or coma), which are usually not present in MS. In addition, in most cases, ADEM occurs only once, while people with MS have further, repeated attacks of inflammation in their brains and spinal cords.
Most cases of ADEM occur about 7 to 14 days after an infection, or up to three months following a vaccination. The most commonly associated infectious agents include cytomegalovirus (CMV), Epstein-Barr virus, herpes simplex virus, human herpes-virus-6, influenza virus, hepatitis A, HIV, and mycoplasma pneumonia. Associated vaccines have included rabies, measles, pertussis, tetanus, influenza, hepatitis B, diphtheria, rubella, pneumococcus, varicella, smallpox, human papillomavirus and poliomyelitis.
In many cases of ADEM, no preceding infection or "trigger" is identified.
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
MS is the main differential diagnosis. The differentiation between ADEM and a first episode of MS can be very difficult but has important prognostic and treatment implications. Differential diagnosis also includes infectious encephalitis, Guillain-Barré syndrome, glioblastoma multiforme, Schilder's disease (see these terms), psychotic disorders with acute onset, toxic/metabolic encephalopathy, vasculitis, nonvasculitic autoimmune encephalopathy, meningitis, metastatic tumor.
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 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.
- 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 Multiple Sclerosis Society provides information on acute disseminated encephalomyelitis (ADEM). Click on the above link to access 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.
- The Transverse Myelitis Association provides information about acute disseminated encephalomyelitis (ADEM).
- The The Cleveland Clinic Web site has an information page on Acute disseminated encephalomyelitis. Click on the Cleveland Clinic link to view this page.
- 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.
- 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 Acute disseminated encephalomyelitis. Click on the link to view a sample search on this topic.
- NINDS Acute Disseminated Encephalomyelitis Information Page. National Institute of Neurological Disorders (NINDS). https://www.ninds.nih.gov/Disorders/All-Disorders/Acute-Disseminated-Encephalomyelitis-Information-Page. Accessed 7/26/2017.
- Acute Disseminated Encephalomyelitis (ADEM). National Multiple Sclerosis Society. https://www.nationalmssociety.org/What-is-MS/Related-Conditions/Acute-Disseminated-Encephalomyelitis-(ADEM). Accessed 7/26/2017.
- Brenton JN. Acute Disseminated Encephalomyelitis. Medscape Reference. Dec 19, 2016; https://emedicine.medscape.com/article/1147044-overview#showall.
- Foris L, Dulebohn S. Disseminated Encephalomyelitis, Acute. StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; May 15, 2017; https://www.ncbi.nlm.nih.gov/books/NBK430934/.