About Pediatric Multiple Sclerosis
MS is an autoimmune condition that affects the central nervous system: the brain, spinal cord, and eye [optic] nerves.
The body's immune system works to attack infections (bacteria and viruses) to keep the body healthy. In autoimmune conditions, the body’s immune system attacks a normal part of the body, such as the brain, kidneys, or skin.
In MS, the body's immune system, for unclear reasons, causes inflammation that attacks and injures the insulation (called 'myelin') around nerves in the brain and spinal cord. The injured nerve cannot function properly, and this leads to various neurological symptoms. A characteristic of MS is that these inflamed areas occur in various places in the brain and/or spinal cord, and occur repeatedly over time. These areas of inflammation typically can be seen on an MRI scan and are referred to as lesions or plaques.
There are different subtypes of MS, but each is considered a chronic condition, meaning it cannot be cured and is present throughout one’s life-although there are treatments available to lessen the severity of the disease. Here are the most common subtypes:
- Relapsing-remitting MS - This is the most common type of MS (>95% of pediatric patients). This subtype causes distinct relapses of inflammatory lesions in the brain that correlate with new symptoms, like visual loss, or numbness in the left arm and leg. Patients usually recover partially or completely from these relapses, but they do occur repeatedly over time.
- Secondary progressive MS - This subtype of MS arises after many years of relapsing-remitting MS (typically between 20-40 years in children). In this phase of the condition, patients may experience a slow steady increase in symptoms, including walking and balance difficulties, dizziness, visual problems, muscle stiffness, weakness, and sensory loss.
- Primary progressive MS - This rare subtype causes steady progression of symptoms from the beginning of the disease. It almost never occurs in children.
What is Clinically-Isolated Syndrome (CIS)?
CIS is a first-time event of the immune system, causing inflammation and damage to the nerve cells' myelin (as described above). It may or may not be an indication that a person has MS, as the likelihood of developing MS depends on several factors, including the type of symptoms and the results of an MRI scan, lumbar puncture, and/or blood tests. Depending on further work-up, the risk that this syndrome could lead to a diagnosis of MS typically ranges from 20 to 80 percent.
How common is MS in children?
There is a common misconception that MS cannot occur in children, but this is not true. About 5 percent of all the MS patients in our area present with symptoms prior to the age of 18 years. It is much more common to be diagnosed during adulthood. In the greater Rochester area, there are five to ten new cases of either MS or a related disorder for every one million people every year.
What causes MS/CIS?
The cause of MS is still not entirely understood. The cause is felt to be an immune system mediated attack on the neuron’s myelin (insulation). The reason for the immune attack is not clear. It is most likely that the condition arises from the interplay between genetic predisposition and environmental factors.
Genetic predisposition - Those with a family history of autoimmune diseases (MS, lupus, rheumatoid arthritis, Crohn's disease) have a slightly increased risk.
Environmental factors - There are certain factors that have been associated with increased susceptibility to MS, although the exact relationship between these factors and MS is not well understood. The following are known to increase the risk of developing MS:
- Exposure to Epstein-Barr virus, which causes infectious mononucleosis or mono. Exposure to this virus is quite common in children—about two-thirds of children tested have been exposed, and only a tiny fraction of these develop MS.
- Reduced sunlight exposure and low vitamin D levels
- Smoke exposure
- There is NO clear evidence that any vaccinations increase the risk of developing MS.
What are the symptoms of MS/CIS?
Individuals with MS have symptoms of neurologic problems relating to relapses of inflammation in the brain and/or spinal cord (as discussed in What is MS?), as well as bothersome symptoms not necessarily related to relapses. These symptoms are very variable, and some may experience lots of symptoms, while others may experience relatively few. The symptoms experienced also frequently fluctuate over time, and can be influenced by illness or stress.
MS relapses - These typically partially or completely recover over a period of several days to several months.
Bothersome symptoms that are not necessary related to a relapse include:
- Visual loss in one eye or double vision
- Numbness in a part of the body (face, arm, leg, trunk)
- Weakness or clumsiness in a part of the body or face
- Dizziness, imbalance, or walking difficulty
- Problems with urination or bowel movements
- Speech or language difficulties
- Fatigue (tiredness)
- Headaches
- Depression
- Slow thinking or memory difficulties
- Problems with urination or bowel movements
- Muscle spasms
- Pain
- Worsening of symptoms with heat
How are MS and related conditions diagnosed in children?
There is no one test that completely confirms or excludes these conditions. We use a combination of an individual’s history of symptoms, examination findings, and additional testing to reach a diagnosis.
Additional testing may include:
- MRI scan (picture) of the brain and/or spinal cord
- Blood tests looking for other conditions that can cause inflammation
- Spinal tap (lumbar puncture) to evaluate for evidence of inflammation in the spinal fluid (fluid that bathes the brain and spinal cord)
- Visual evoked potential, an evaluation to determine if the nerve transmission from the eye is functioning normally
What are the treatment options for children with MS?
The treatment of MS falls into 3 general categories:
- Treatment for an ongoing MS relapse. The treatment recommended for MS relapses is typically an intravenous (IV) steroid for three to five days. This steroid is different from performance-enhancing steroids that athletes use. The treatment can be done in the hospital, in an outpatient infusion center, or at home with a visiting nurse. Rarely, other treatments may be needed if the symptoms are not improving with the steroid infusions.
- Long-term maintenance therapy to decrease MS relapses over time and slow down the disease course. In adults, there are approved disease-modifying therapies that have been shown to help decrease MS relapses over time, and potentially slow down the early phases of disease. These same therapies are often used in children, and are generally, but certain adult treatments are used with children and are generally considered safe and effective. For the most part, these are injectable therapies.
- Treatment to help with bothersome symptoms. There are numerous medications for the treatment of the bothersome symptoms listed above.