Health officials have still been unable to find definitive answers to the cause and treatment for acute transverse myelitis (ATM)— paralytic condition associated with inflammation in the spinal cord. Historically, the first ATM cases were described in 1882, but the term “acute transverse myelitis” was not used until 1948.1 Now, the estimated incidence is approximately 1,400 people annually.2 Since August 2014, the Centers for Disease Control and Prevention (CDC) has reported 386 cases. In 2018 alone, there have been two new cases.3
ATM, which has been described as a “polio-like” illness, remains of a mystery. Medically-speaking, it is an acute inflammation of the entire width of the spinal cord (transversely), which blocks nerve impulse transmissions traveling up or down the spinal cord. Patients typically feel sudden pain their back and a band-like tightness. Tingling, numbness and muscle weakness spread throughout the body during the following days. The patient feels the need to urinate, but urinating becomes difficult. Symptoms may persist in severity, sometimes resulting in paralysis, loss of sensation, retention of urine and loss of bladder/bowel control.4 5
These symptoms mirror other disorders, such as Guillain-Barré Syndrome (GBS), which is why doctors have difficulty with the diagnosis of ATM. MRIs show cord swelling and can help exclude spinal cord compression as a diagnosis. Collection of cerebrospinal fluid via spinal tap is another method to analyze the question of ATM as the fluid presents with more protein than usual and a higher number of white blood cells.6 7
Treatments are meant to address the infections causing ATM, reduce inflammation and manage other symptoms. One third of people with a diagnosis of ATM recover, while the rest continue to experience muscle weakness and urinary problems. Some people with severe ATM are confined to a wheelchair.
The biological mechanism of ATM and why some people develop it remains unknown. People with autoimmune conditions, such as multiple sclerosis or lupus, maybe be more prone to developing ATM. Similarly, those with certain bacterial and viral infections, such as Lyme disease and tuberculosis may also be more susceptible. Specific antiparasitic or antifungal drugs, as well as intravenous heroin or use of amphetamines, could also be a risk factor for triggering ATM.
Additionally, ATM has been associated with vaccine reactions. ATM seems to be triggered by an autoimmune response by the body, i.e., the immune system misinterprets the body’s tissues as foreign, thus producing antibodies that attack tissues, in this case in the spinal cord.8 9
Between 1922 and 1923, there were 200 cases of ATM noted as complications of the smallpox and rabies vaccines in England. Later reports showed transverse myelitis was post-infectious.
ATM has been reported following vaccinations and there have been awards made for vaccine-associated transverse myelitis in the U.S. Court of Federal Claims, also known as “Vaccine Court,” through the federal vaccine injury compensation program (VICP) created under the National Childhood Vaccine Injury Act of 1986.10
The National Organization for Rare Disorders states that one theory is that the vaccine “may have excited an autoimmune process.”11
More recently, myelitis appears to be most common following polio,12 hepatitis B and influenza13 vaccines. A review of studies published between 1970 and 2009 identified 37 documented cases of transverse myelitis linked with hepatitis B, MMR (measles, mumps and rubella) and Tdap (tetanus, diphtheria and acellular pertussis) vaccines.14 Another review of studies from 1979 to 2013 revealed 24 cases of post-vaccination myelitis.15
A 2016 study analyzed a possible causal effect between vaccines and subsequent transverse myelitis or acute disseminated encephalomyelitis using data from the Vaccine Safety Datalink between Jan. 1, 2007 and Dec. 31, 2012. Patients with a history of multiple sclerosis and neuromyelitis optica spectrum disorders were excluded.
In the seven cases of transverse myelitis that occurred during the study period, researchers did not find a statistically significant higher risk of a demyelinating event after vaccine exposure. However, in eight cases of acute disseminated encephalomyelitis, researchers did identify a statistically significant association with the Tdap vaccine within five to 28 days. They determined the excess risk to not be more than 1.16 cases of ATM per million vaccines administered.16 17
ATM Similar to AFM
The ATM story may sound similar to acute flaccid myelitis (AFM), or acute flaccid paralysis (AFP), which mostly affects young children. Public health officials are still trying to determine why young healthy children are being paralyzed by AFM. For most of the observational cases recorded, the polio-like symptoms were experienced when the spinal cord became inflamed. These symptoms include fever, respiratory issues and gastrointestinal problems.18
Some doctors and researchers speculate that AFM could be caused by immune dysfunction and autoimmunity.18 According to the CDC, there have been 134 cases of AFM across 33 states, but additional cases are still under investigation.19
1 Traverse Myelitis. National Organization for Rare Disorders Nov. 27, 2018 (accessed).
2 Acute Transverse Myelitis: Consumer Version. Merck Manual Nov. 20, 2018 (accessed).
3 Morse Silva, B. Health Check Kids: Acute transverse myelitis. NBC 10 News Oct. 25, 2018.
4 See Footnote 2.
5 Transverse Myelitis Fact Sheet. National Institute of Neurological Disorders and Stroke Nov. 28, 2018 (accessed).
6 Acute Transverse Myelitis: Professional Version. Merck Manual Nov. 20, 2018 (accessed).
7 See Footnote 5.
8 See Footnote 2.
9 See Footnote 5.
10 U.S. Court of Federal Claims. Vaccine-Reported Opinions (search for documents mentioning ‘transverse myelitis’).
11 See Footnote 1.
12 Kelly, H. Evidence for a causal association between oral polio vaccine and transverse myelitis: A case history and review of the Literature. Journal of Paediatrics and Child Health 2006; 42: 155-9.
13 Lieverman A, Curtis L. HSV2 reactivation and myelitis following influenza vaccination. Human Vaccines & Immunotherapeutics 2017; 13: 572-3.
14 Agmon-Levin N, Kivity S and Szyper-Kravitzmore M. Transverse myelitis and vaccines: a multi-analysis. Lupus 2009; 18: 1198-1204.
15 Karussis D and Petrou P. The spectrum of post-vaccination inflammatory CNS demyelinating syndromes. Autoimmunity Reviews 2014; 13: 215-224.
16 Baxter R, Lewis E, Goddard K, et al. Acute Demyelinating Events Following Vaccines: A Case-Centered Analysis. Clinical Infectious Diseases December 2016; 63: 1456-62.
17 Acute Demyelinating Events Following Vaccines: A Case-Centered Analysis. The Transverse Myelitis Association July 6, 2017.
18 Cáceres M. AFM Compared to Guillain-Barre Syndrome. The Vaccine Reaction Nov. 21, 2018.
19 Goldschmidt D. Polio-like illness AFM ‘appears to have peaked’ in US for the year. CNN Dec. 3, 2018.