We all know that the air we breathe and the soil we walk on
are full of micro organisms like bacteria, virus and fungii. Though we are surrounded by micro organisms we
seldom fall sick. This is because our immune system fights off bacterial and
viral infections. Immune system is a complex
network of specialized cells and organs that work together to defend the body
against attacks by foreign invaders, such as bacteria and viruses. The immune
system can be classified as innate immune system & acquired immune system. The
innate immune system is more primitive and it employs types of
white blood cells called granulocytes and monocytes to destroy harmful
substances. The acquired immune system is the part of the immune system that
develops as a person grows. It employs antibodies and specialized white blood
cells to fight harmful substances.
The body forms antibodies to fight bacteria and virus
attacks. Each time a new bacteria or virus attacks us our body forms a specific antibody to counter
it. Sometimes these antibodies mistake our body parts for micro organisms and
it starts attacking the body by mistake. This is called auto immune disorders.
Autoimmune diseases can occur in the eyes. When the white
outer cover of the eye is attacked by our own antibodies we develop a painful
condition called scleritis. When the inner coat of the eye called uvea is
attacked the condition is called uveitis.
Uveitis usually presents
with redness in the eyes and hence can be mistaken for conjunctivitis or madras
eye. As opposed to conjunctivitis delayed treatment can cause permanent
blindness. Uveitis is estimated to be
responsible for approximately 10% of the blindness in the United States.
The main differentiating factor between uveitis and conjunctivitis is pain
which is usually always present in uveitis but is absent in conjunctivitis.
Uveitis can be caused by autoimmune disorders such as
rheumatoid arthritis or ankylosing spondylitis, infection, or exposure to
toxins. However, in many cases the cause is unknown.
Uveitis can be
associated with any of the following:
·
AIDS
·
Ankylosing spondylitis
·
Herpes zoster infection
·
Injury
·
Psoriasis
·
Rheumatoid arthritis
·
Sarcoidosis
·
Syphilis
·
Toxoplasmosis
·
Tuberculosis
Symptoms
·
Blurred vision
·
Dark, floating spots in the vision
·
Eye pain
·
Redness of the eye
·
Sensitivity to light
Treatment
·
Dark glasses to lessen photophobia
·
Eye drops that dilate the pupil to relieve pain
·
Steroid eye drops
·
Uveitis treatment depends on the underlying
cause but almost always includes steroids taken by mouth. Additional
specialists in infectious disease or autoimmunity may be needed for such
diseases as syphilis, tuberculosis, AIDS, sarcoidosis, or Behcet syndrome.
·
If the uveitis is caused by a body-wide
infection, treatment may involve antibiotics and powerful anti-inflammatory
medicines called corticosteroids.
Expectations
(prognosis)
With proper treatment, most attacks of anterior uveitis go
away in a few days to weeks. However, relapses are common.
Inflammation related to posterior uveitis may last from
months to years and may cause permanent vision damage, even with treatment.
Key Words
Antibody – A
special protein produced by the body’s immune system that recognizes and helps
fight infectious agents and other foreign substances that invade the body.
Antigen – A
foreign substance that triggers the production of antibodies when it is
introduced into the body.
Autoimmune disease
– A disease that results when the immune system mistakenly attacks the body’s
own tissues.
Corticosteroids –
Potent anti-inflammatory hormones that are made naturally in the body or
synthetically (man-made) for use as drugs. They are also called
glucocorticoids. The most commonly prescribed drug of this type is prednisone.
Immunosuppressive
drugs – Drugs that suppress the immune response and can be used to treat
autoimmune disease. Unfortunately, because these drugs also suppress normal
immunity, they leave the body at risk for infection.
Inflammation – A
reaction of body tissues to injury or disease, typically marked by five signs:
swelling, redness, heat, pain, and loss of function.
