Iritis

ANATOMY

Uveitis is inflammation inside the eye, specifically affecting one or more of the three parts of the eye that make up the uvea: the iris (the colored part of the eye), the ciliary body (behind the iris, responsible for manufacturing the fluid inside the eye) and the choroid (the vascular lining tissue underneath the retina). The structures of the uvea, marked here in red, are collectively known as the uveal tract.

SYMPTOMS
The symptoms of iritis include light sensitivity, red eye, blurred vision, tearing, pain, and sometimes floaters. The pupil may appear small in the affected eye when compared to the normal pupil. Frequently iritis is a recurrent problem; after a few episodes patients become very astute at early diagnosis. Iritis is sometimes confused with conjunctivitis (as was my initial diagnosis in Sept, 2006), a much less serious disorder of the clear outer lining of the eye.

DIAGNOSIS
When the iris is inflamed, white blood cells (leukocytes) are shed into the anterior chamber of the eye where they can be observed on slit lamp examination floating in the convection currents of the aqueous humor. These cells can be counted and form the basis for rating the degree of inflammation.

TREATMENT
The secrets to the successful treatment of iritis is early detection and proper choice of medicines. Therapy consists of anti-inflammatory and dilating drops. These medicines decrease the inflammation and reduce the scarring that can occur. Both steroids and antibiotics may be used. Persistent cases may require more intensive treatment. Successful treatment of iritis depends on careful and consistent compliance by the patient. The application of hot packs may also provide relief from the symptoms of iritis. In severe cases, oral medications and injections may be necessary to treat the condition.

COMPLICATIONS
Uveitis is a serious ocular condition. It is the third leading cause of blindness worldwide, accounting in the United States for 10-15% of all blindness. Untreated or under-treated uveitis, or repeated episodes of inflammation within the eye, can lead to scarring and blinding consequences. Uveitis is a treatable condition.

Ankylosing spondylitis affects the eyes in up to 40 percent of cases, leading to episodes of eye inflammation called acute iritis. Iritis--a form of Anterior Uveitis--is a term for an inflammatory disorder of the iris. In the majority of cases there is no specific cause. Occasionally, iritis is just one symptom of a disease that affects other organ systems. These are called connective tissue diseases and include: rheumatoid arthritis, sarcoid , lupus , scleroderma , Behcet's disease , anklylosing spondylitis, Reiter's disease, Crohn's disease, ulcerative colitis, and B-27 disease. Sometimes, it is necessary to establish whether iritis/uveitis is a manifestation of one of these or some other underlying systemic disease.

In serious cases, complications may arise. Cataracts, glaucoma, and corneal changes are possible consequences of both the disease and the medicines used to treat it. Uveitis is the third leading cause of blindness in the United States. The prevalence of blindness secondary to uveitis has not changed in the past forty years. Careful observation is needed in the resolving phase to monitor potential problems. If the medicines are withdrawn too rapidly, a recurrence is very possible. Rarely, ankylosing spondylitis can also have serious complications involving the heart and lungs. A longitudinal study of disease activity and functional status in a hospital cohort of patients with ankylosing spondylitis (2004) indicates that iritis and late onset disease may be severity markers for functional impairment.

References:
Rheumatology (Oxford). 2004 Dec;43(12):1565-8. Epub 2004 Sep 7