There are many diseases that are so similar in nature to multiple sclerosis that they are considered to be borderline multiple sclerosis. Acute disseminated encephalomyelitis (ADEM) is one of these diseases. This immune system disease is a disease that attacks the brain and typically occurs after a viral infection although there are other causes.
ADEM usually occurs in children and is not highly prevalent, occurring on about 8 out of every 1,000,000 people. While this is not a high rate, parents who are coping with ADEM need to learn about the disease, what causes it and how it is treated in order to feel more confident that their child will recover. Adults may also be diagnosed with ADEM although their onset is not typically related to vaccinations.
Causes
ADEM may be caused by viral infections, bacterial infections, vaccinations, and organ transplants. A more detailed breakdown of the cause of this disease follows:
- Viral Infections: Herpes simplex, hepatitis A, Epstein Barr, cytomegalovirus, influenza, measles, mumps, rubella, coxsackievirus, and varicella zoster.
- Bacterial Infections: Beta-hemolytic Streptococci, Borrelia burgdorferi, Mycoplasma pneumonia, and Leptospira.
- Vaccinations: It is important to note that the only vaccine that has been proven to be linked to ADEM is a form of the rabies vaccine known as Semple; however, other vaccines have shown to be linked to ADEM, including vaccines for measles, mumps, hepatitis B, diphtheria, pertussis, polio, and pneumococcus.
Further investigations into the causes of ADEM are being conducted, particularly in the cases thought to be related to vaccinations. These tests have caused many parents to question the vaccinations that pediatricians recommend for their children.
Symptoms
The symptoms associated with acute disseminated encephalomyelitis usually appear within a few weeks of being exposed to the virus or having been vaccinated. Symptoms usually include:
- Fever with no obvious origin;
- Headache
- Extreme drowsiness
- Seizures
- Coma
Initially these symptoms may appear mild; however, if the culprit behind them is ADEM, they worsen quickly, typically in about 4 days with the most severe symptoms being cranial nerve palsies, extreme weakness on one side of the body (hemipareiss) and even paralysis of the lower body (paraparesis). Fortunately, most children who have ADEM are under a doctor’s care before these severe symptoms occur.
Treatment
Treating ADEM involves an aggressive attack on the central nervous system with medications that will reduce the inflammation. Steroids, typically corticosteroids, are given intravenously until the body begins to respond. These are followed by a longer cycle of oral steroids such as prednisone. The length of the prednisone dosing plays a large role in how well the patient responds and maintains there wellness. Three weeks of oral steroids has been shown to be at least the minimum amount of time needed to increase recovery chances.
Recovery
The good news for parents of children with ADEM is that 50 -70% of cases have a full recovery over a period of time ranging from 1-6 months. Approximately 70-90% of ADEM patients will recover with only minor disabilities assessed when the condition is gone. The highest rate of death associated with ADEM is in patients that are not able to tolerate steroid therapy, have sever, sudden onset of the disease or have extreme neurological effects from the disease. Children have a better recovery rate than adults as do those cases that present with fever versus those that have no fever.
Comparing ADEM to MS
As stated previously, many doctors and scientists consider ADEM to be part of a family of diseases that are linked to multiple sclerosis. The two diseases are very similar in that they both involve damage to the protective covering of the nerves in the central nervous system that are associated with the autoimmune system.
Like multiple sclerosis, ADEM patients can suffer from cognitive disability even when there are no obvious physical disabilities. The cognitive disabilities seen with ADEM are typically less severe than those seen in patients with MS.
There is no majority agreement that places ADEM and MS in the same class of disease; in fact, there is not a completely and totally agreed upon definition for multiple sclerosis as it can encompass a host of disease and symptoms. One definition of MS labels it as a disease with inflammatory lesions that affect the CNS – this is the definition that ADEM fits in with perfectly. A more technical definition of MS, based on the location of the offending plaque shows the two to be entirely different– distinctly in the white matter in MS and more broadly spread out with not distinct definition in ADEM. These differing definitions explain why some doctors consider ADEM to be borderline MS and some do not.
ADEM is a dangerous disease that can be contracted by viral infection and possibly from certain vaccinations. The good news is that treatment options are vast and the prognosis for recovery is high.

