Tuesday, June 14, 2011

Related Diseases, part 2: Sjögren's Syndrome


          Sjögren's Syndrome is characterized by unusually dry eyes and/or mouth. For simplicity’s sake I’m going to focus on the eyes in this post, but the biology behind the dry mouth is more or less the same.

            Eyes are normally kept healthy and moist by tears secreted by tear glands near the eye. In Sjögren's Syndrome patients, however, the glands that normally keep your eyes moist are attacked by… say it with me, everyone… the immune system. As the tear glands are damaged they stop secreting enough tears, and the eyes dry out.

Seriously? This is a real disease?

To someone without Sjögren's Syndrome, dry eyes probably doesn’t sound like a big deal. But think about it… you use your eyes all day, every day. If they are much drier than they should be it means that they are always uncomfortable. If you’d really like to know how it feels, I suggest the following experiment:

  1. Find some sand.
  2. Put the sand in your eyes.
  3. Go about your normal daily routine for a couple of months.
  4.  Don’t sue Sam, who is not seriously suggesting that adding sand to eyes is a good idea.

            Not only are dry eyes very uncomfortable, they can also lead to infections. Eyes are normally protected by IgA antibodies, which are secreted in tears (among other places). In a healthy person, these antibodies are weapons used against invading germs. Not having enough tears therefore means that the eye is more vulnerable to infections.

Can’t you just use eye drops, artificial tears, etc?
In a healthy person, tear glands near the eye constantly secrete a small amount of tears. If the tear glands aren't working properly, then your eyes never have enough moisture. Since it is impossible for someone to add artificial tears every time (s)he blinks, using them several times a day may not be enough to keep the eye healthy.

How is Sjögren's Syndrome treated?
            As usual with autoimmune diseases, there is no cure for Sjögren's Syndrome. There are, however, a number of different ways either to help alleviate the symptoms, or to treat the underlying autoimmune disease. The drugs used to treat the underlying disease vary quite a bit, depending on what other diseases are present, the severity of the disease, etc. Methods that aim to treate the immediate problem of dryness include the following:

1.     Artificial Tears: To prevent damage to  the eye, patients use artifical tears frequently. By “frequently” I mean “Patients buy them in bulk from Costco.”
2.     Restassis Eye-drops: Restassis drops contain an immunosuppressant, which helps decrease the inflammation around the eye. This allows the tear glands to start working properly again.
3.     Punctal plugs: Eyes have ducts that act like drainpipes, removing excess tears. An opthamologist can block these ducts, which makes it so that what little moisture is secreted into the eye will stay there.

As I mentioned earlier, people who are otherwise healthy can be diagnosed with Sjögren's Syndrome. It is also worth noting that many patients with other autoimmune diseases can have the symptoms of Sjögren's Syndrome, but not be diagnosed with it. There is enough overlap between autoimmune diseases that a doctor may not feel that it is necessary to give a formal diagnosis. Sjögren's patients are also far more likely to be diagnosed with peripheral neuropathies, such as carpal tunnel syndrome.

Update: Venus Williams, the famous tennis player, has recently been diagnosed with Sjögren's syndrome. It is unsurprisingly making it more difficult for her to compete.

Additional notes:
My usual disclaimer applies. I am not a physician. Please do not ever use my explanations as a substitute for talking to your doctor! 
Also, I am not a physiologist, nor is anatomy my strong point. I have presented the information to the best of my knowledge and ability, but there may be inaccuracies of which I am unaware.... And, seriously folks, don't try putting sand in your eye.
Sources: 
http://www.lupus.org/webmodules/webarticlesnet/templates/new_learnaffects.aspx?articleid=2380&zoneid=526
http://www.mayoclinic.com/health/sjogrens-syndrome/DS00147
http://www.sjogrens.org/home/about-sjogrens-syndrome/sjoegrens-faqs

1 comment:

  1. It's not so much like having sand in your eyes, it's more like having a fan on high in front of your face all the time. The second you open your eyes they dry up and sting and itch. At least that's how I feel it...

    ReplyDelete