Multiple sclerosis is damage to the insulation, not the wire

Multiple sclerosis affects the brain and spinal cord — the central nervous
system. Specifically, it damages myelin, the protective coating around
nerve cells that helps nerves send messages quickly. Damaged myelin means
messages between brain and body slow down or get blocked, and that is what
produces the symptoms.

The insulation analogy is worth holding, because it explains the disease's
most confusing feature: MS symptoms depend on which nerves are affected,
so two people with the same diagnosis can have almost nothing in common.

Five named patterns

The last two exist because MRI can now see the damage before the person feels
anything, which creates a category of people who have the picture of a disease
without the disease.

What causes it

Nobody knows exactly. Many believe it is autoimmune — the immune system
mistakenly attacking healthy cells, here the myelin. Several factors appear to
combine:

• A previous Epstein-Barr virus infection — the most common cause of
  mononucleosis
• Environment — smoking, little sun exposure, low vitamin D
• Genes — certain genes raise risk, and **not everyone carrying them gets
  MS**
• Family history — a close relative diagnosed with it
• Sex — MS is two to three times more common in women
• Age — it most often begins between 20 and 40

Symptoms

Blurry or double vision, or eye pain (often from optic neuritis). Trouble with
bladder control. Muscle weakness. Muscle stiffness or spasms. Trouble with
coordination, walking or balance. Numbness, tingling or pins and needles.
Thinking or memory problems. Fatigue. Dizziness or vertigo. Mood changes.

Some people have mild symptoms; others have more serious problems.

Diagnosis without a single test

There is no specific test for MS. A provider assembles a diagnosis from:

• A review of health history and symptoms
• A physical and neurological exam — reflexes, strength, senses
• An MRI looking for damage in the brain and spinal cord
• Blood tests to rule out other conditions
• A lumbar puncture, checking the fluid around brain and spinal cord for
  signs of MS

Treatment

There is no cure, and treatment manages symptoms and slows the disease:

• Disease-modifying medicines — pills, injections or infusions, slowing MS
  and reducing relapses
• Medicines for individual symptoms, such as stiffness or pain
• Physical and occupational therapy for movement, strength and daily
  activities

Living with MS affects how you feel emotionally. What helps: reducing stress,
connecting with supportive people, eating well, and staying as active as you
comfortably can.

*Source: National Institute of Neurological Disorders and Stroke, via
MedlinePlus.*