Iritis is actually a subset of a group of diseases known as uveitis. This refers to swelling, or inflammation, of the iris -- the colored part of the eye. This condition can be characterized by extreme sensitivity to light, a red "ring" around the colored part of the eye, and in some cases, pain and blurred vision.

Iritis, or other forms of uveitis, can frequently be a sign of an underlying systemic condition. For example, rheumatoid arthritis, lupus, tuberculosis, sarcoidosis, and many other conditions, can result in iritis.

As in many conditions, early treatment is very important in iritis. It can result in far more rapid resolution of the patient's symptoms, reduce the frequency of recurrences, and reduce the complications of this condition, which can include damaging scarring within the eye.