The review by Martino et al mentioned various forms of Multiple Sclerosis (MS) without any real description or delineation of the disease types. Patients who suffer from MS are diagnosed with one of four forms of the disease.
1. Relapsing-Remitting (85% of patients are diagnosed with this form of the disease) In this form, patients exhibit clearly defined flare-ups (relapsing stages of inflammation) followed by clearly defined remissions (inflammation subsides). In between relapses and remissions, patients report feeling "disease free."
2. Primary Progressive (10% of patients) Patients with this form of MS exhibit a slow, continuous worsening of their disease without clearly defined relapses and remissions.
3. Secondary Progressive (50 % of Relapsing-Remitting patients will deteriorate into this form of MS within 10 years of their initial diagnosis) This form is characterized by the initial relapsing-remitting state of MS followed by a steady decline in the health of the CNS. Secondary Progressive MS differs from Primary Progressive in that patients may experience small remissions in their condition.
4. Progressive-Relapsing (5% of patients) Progressive-Relapsing MS is defined by a continual worsening of the disease with obvious acute relapsing phases.
The various types and progressions of MS seem to be indicative of different pathologies of inflammation. What is static between all four forms of the disease is the fact that immune cells are attacking the oligodendrocytes within the CNS and the Schwann cells in the PNS that are responsible for myelination of the nervous system. Furthermore, gadolinium (the contrast used in MRI imaging of the disease) may enhanced MS inflammatory episodes, initiating more lesions to form in the nervous system. These factors make it necessary for therapies to be created to treat each form of MS as most treatments now only treat relapsing forms of the disease (only when diagnosed early enough).
There is a drug on the market currently for Relapsing-Remitting MS called Tysabri. This drug is a monoclonal antibody which deters immune cells, which may be detrimental to the nervous system, from entering the blood stream, and eventually the blood brain barrier. Patients receiving this treatment experience fewer relapses. This drug was temporarily removed from the market as several patients contracted a rare, fatal brain disease called leukoencephalopathy. After reconsideration by the FDA, Tysabri was re-released with new guidelines.
Tysabri has not been tested on the other three forms of MS, but as it possibly prevents damaging immune cells from entering the blood brain barrier and the CSF it may be a new good avenue of research.
Mayo Clinic. "Multiple Sclerosis: Treatment." 6 Dec. 2006. http://www.mayoclinic.com/health/multiple-sclerosis/DS00188/DSECTION=7
National Multiple Sclerosis Society. "Tysabri (Natalizumab)." 9 Oct. 2007. http://www.nationalmssociety.org/site/PageServer?pagename=HOM_LIVE_meds_natalizumab
National Multiple Sclerosis Society. "What is Multiple Sclerosis". 3 Aug. 2006. http://www.nationalmssociety.org/site/PageServer?pagename=HOM_ABOUT_what_is_ms
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I didn't know anything about multiple sclerosis, so I wikipedia searched it real quick and found
Multiple sclerosis (abbreviated MS, also known as disseminated sclerosis or encephalomyelitis disseminata) is a chronic, inflammatory, demyelinating disease that affects the central nervous system (CNS). MS can cause a variety of symptoms, including changes in sensation, visual problems, muscle weakness, depression, difficulties with coordination and speech, severe fatigue, cognitive impairment, problems with balance, overheating, and pain. MS will cause impaired mobility and disability in more severe cases.
Maybe i'm the only one who didn't know anything about this disease, but I found that little description helpful.
As for the "In search of Lost Time" article, I found it VERY interesting that they prescribed adderol for her "mental fog" problem. I'm prescribed adderol, and after about a year of being on it, I do have to say that it has COMPLETELY changed my mental state and memory accumulation.
In high school, I was a valedictorian, and school was a breeze for me. However, in my daily life, I lost EVERYTHING CONSTANTLY. I would lose my wallet 3, 4, sometimes 5 times a day. Since being prescribed adderol, I NEVER lose my stuff anymore, but my school skills are slowly deteriorating. I used to be a great test taker, and now I constantly know everything on a test and still do poorly on the tests. I'm not sure if this is any importance to the article, but I can say that completely boosted my short term memory during every-day activities, and I could see how it would help people with memory loss.
For clarification, the 3 patients on Tysabri that contracted PML (from which two died) were also taking an interferon called Avonex.
PML is frequently seen in AIDS patients. If I remember correctly, the JC virus, which is latent in about 75% of the population, was allowed to reactivate because immune surveillance of the CNS was greatly attenuated by not allowing 'detrimental' immune cells in the brain. Maybe they are not ALL detrimental.
This mAb is targeted against an integrin which prevents most leukocytes from entering the CNS. So how then would a resurging virus, like JC, be detected by our immune system? By the time one knows they have PML, it's pretty much too late.
With only two year data on this drug, we can only wait and see what long term effects (good and bad) may be.
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