Multiple sclerosis is a complex disease of the central nervous system
that also involves the peripheral nerves of the brain and spinal cord.
At present, the specific causes of multiple sclerosis are unknown, and
thus the disease can’t be efficiently prevented or cured. However, the
good news is that multiple sclerosis is not a life-threatening disease
and that the existing treatments can successfully keep its generated
symptoms under control. With the aid of an appropriate course of
treatment, the progression of the disease can be slowed down and
patients with multiple sclerosis can live active, normal lives.
Multiple sclerosis is known to occur on the premises of myelin
destruction. Myelin is a fatty substance that covers nerve cells,
accomplishing a series of vital roles at the level of the nervous
system: apart from protecting nerve cells and tissues from damage,
myelin also facilitates the transmission of nervous impulses throughout
the body. When demyelination occurs, (the process of myelin
destruction, which also results in hardening of the nervous tissues)
the entire nervous system becomes impaired, generating a wide variety
of specific symptoms. The intensity of the symptoms produced by
multiple sclerosis and the progression of the disease are strongly
influenced by the proportions of the demyelination process and the
location of the hardened lesions.
According to the intensity and frequency of its generated symptoms, as
well as its rate of progression, multiple sclerosis can be categorized
in two distinctive groups: the relapsing-remitting type and the
chronic-progressive type. The chronic-progressive variety of multiple
sclerosis can be further categorized as primary-progressive,
secondary-progressive and progressive-relapsing.
The relapsing-remitting type of multiple sclerosis is the most common
form of the disease and it predominantly affects young and middle-aged
persons. The major characteristic of the relapsing-remitting type of
multiple sclerosis is that its generated symptoms are mild and tend to
occur in flares. After short periods of symptomatic flare-up, the
disease goes into remission, producing no perceivable symptoms for
periods of a few weeks or even months. The periods of remission usually
occur naturally, although immunosuppressive drugs can also influence
the occurrence and the duration of remission periods. However, the
periods of remission are usually followed by short periods of relapse,
characterized by intensification of the overall symptoms.
The chronic-progressive type of multiple sclerosis refers to cases that
are slow-progressing and don’t involve spontaneous periods of
remission. Chronic-progressive multiple sclerosis predominantly affects
persons with ages over 45. Around 20 percent of all multiple sclerosis
cases are of chronic-progressive type. Primary-progressive multiple
sclerosis has a predictable pattern of progression, gradually evolving
without periods of remission. This subtype affects around 10 percent of
patients diagnosed with multiple sclerosis. The secondary-progressive
subtype affects about 50 percent of patients diagnosed with the
relapsing-remitting form of multiple sclerosis. Unlike the previously
described subtype, secondary-progressive multiple sclerosis
occasionally involves flare-ups and periods of remission. The
progressive-relapsing subtype is a very rare form of
chronic-progressive multiple sclerosis. This subtype is gradually
progressive and is characterized by short periods of symptomatic
flare-up.
