Iritis
Iritis is an inflammation involving the iris (the colored area of the eye). It is also called anterior uveitis.
Symptoms: sensitivity to light (often severe), redness of the eye (especially in the area where the white of the eye and the iris meet), pain or achiness of the eye or brow area, headache, and sometimes blurred vision. The pupil may be smaller or misshapen in the affected eye.
Diagnosis: Eye doctors diagnose iritis based on microscopic findings on the eye exam. Inflammatory cells in the front part of the eye are key. The number of these cells are monitored on follow up exams to determine treatment. As the inflammatory cells decrease, the amount of medication can be gradually reduced.
Treatment: Iritis must be treated to prevent complications (see below). Steroid eye drops, often starting with very frequent dosing, are the main treatment. Examples of steroid drops include prednisolone acetate, Pred Forte, Durezol, Lotemax, FML, and Flarex.
The drops must be taken consistently at the prescribed interval to be effective. They are tapered slowly based on follow up exam findings. Missed steroid drops, or stopping the drops abruptly or too soon, often leads to return of the iritis. If the iritis recurs, the drop regimen often has to be completely restarted. It is very important to shake the steroid drops well before putting a drop in the eye.
If there is severe pain or scarring of the iris, dilating drops may be prescribed. If the eye pressure is high, medication to lower eye pressure may also be used. Less commonly, if iritis is severe and not responding quickly to treatment, steroid medication may be given as an injection around the eye or in an oral form (pills).
Causes: The majority of iritis cases are idiopathic. This means that no cause is found. For a first case of iritis, if it is involving only one eye, is relatively mild, and responds well to treatment, no testing is needed to determine a cause. Testing is needed to look for an underlying cause of iritis IF: the iritis is recurrent (more than a single episode), involves both eyes, is severe, OR is difficult to treat. Even in these situations, more than half of the time no underlying cause is found.
Testing is done to rule out treatable causes of iritis including autoimmune or rheumatologic conditions, as well as infectious causes from bacteria, fungi, parasites or viruses. Other causes of iritis include trauma to the eye or reactions to certain medications. One of the most common causes of recurrent iritis is a genetic predisposition seen in people who test positive for the HLA B27 genetic marker. Testing for this marker is done in patients with recurrent iritis not only to determine a cause of iritis, but because this marker is also associated with other autoimmune conditions. It is important to remember that even with recurrent, bilateral, or severe iritis, and even when a thorough workup for underlying causes is done, it is common that no cause is found. Nonetheless, testing is important in recurrent, bilateral, or severe cases of iritis in case an underlying and treatable cause is present.
Complications: Treatment of iritis by an eye doctor is important to monitor for complications and try to prevent them. Complications include scarring of the eye structures, high eye pressure or glaucoma, cataract, swelling of the retina, and more severe damage to the eye including blindness. Severe complications are NOT common. It is very important not to self-treat with steroid drops as scarring and elevated eye pressure may not have symptoms until severe and irreversible damage occurs. While steroids are essential to treat iritis, they can also cause cataracts, high eye pressure and glaucoma, so the eye needs to be monitored during treatment. Self-treatment of iritis is dangerous.
