Iritis, also known as anterior uveitis, is an inflammation of the iris (the colored part of the eye) and the surrounding tissue (ciliary body) in the front part of the eye. It is a form of uveitis, which refers to inflammation of the uvea, the middle layer of the eye. Iritis can cause eye pain, redness, light sensitivity, and blurred vision.
Causes:
In many cases, the exact cause of iritis is unknown (idiopathic). However, it can be associated with various factors:
- Autoimmune diseases: Iritis is often linked to systemic autoimmune or inflammatory diseases, including:
- Ankylosing spondylitis
- Rheumatoid arthritis
- Psoriatic arthritis
- Inflammatory bowel diseases (Crohn’s disease, ulcerative colitis)
- Sarcoidosis
- Lupus
- Infections:
- Viral infections (e.g., herpes simplex, herpes zoster, cytomegalovirus)
- Bacterial infections (e.g., tuberculosis, syphilis, Lyme disease)
- Fungal infections
- Parasitic infections
- Eye injury or trauma: A blunt force injury to the eye can trigger iritis.
- Certain medications: Rarely, some medications can cause drug-induced iritis.
- Genetic factors: Individuals with certain genetic markers (e.g., HLA-B27) are more prone to developing iritis, especially when associated with autoimmune conditions.
Symptoms:
Symptoms of iritis can develop suddenly and usually affect one eye, though both eyes can be involved. Common symptoms include:
- Eye pain: Often a deep, aching pain inside the eye, which can worsen with exposure to light or when pressing on the eye.
- Redness of the eye: Particularly around the iris and pupil.
- Photophobia (light sensitivity): Discomfort or pain when exposed to bright light.
- Blurred or hazy vision.
- Small or irregularly shaped pupil: The pupil may appear smaller than the other eye or have an irregular shape due to inflammation.
- Headache: May accompany eye pain.
- Tearing.
Diagnosis:
Diagnosing iritis requires a comprehensive eye examination by an ophthalmologist.
- Medical history and physical exam: The doctor will ask about your symptoms, any underlying medical conditions, and family history.
- Slit-lamp examination: This is the primary diagnostic tool. The ophthalmologist uses a special microscope to examine the front structures of the eye (cornea, anterior chamber, iris, lens) for signs of inflammation, such as:
- Cells and flare (protein leakage) in the anterior chamber.
- Keratic precipitates (inflammatory cells deposited on the back of the cornea).
- Posterior synechiae (adhesions between the iris and the lens).
- Intraocular pressure (IOP) measurement: Eye pressure may be normal, low, or elevated in iritis.
- Dilated fundus examination: To examine the back of the eye (retina and optic nerve) to rule out inflammation in other parts of the uvea (intermediate or posterior uveitis).
- Blood tests and imaging: If an underlying systemic disease or infection is suspected, the doctor may order blood tests (e.g., ESR, CRP, HLA-B27, tests for specific infections) or imaging (e.g., X-rays, MRI).
Treatment:
Treatment for iritis aims to reduce inflammation, relieve pain, prevent complications, and preserve vision.
- Corticosteroid eye drops: These are the primary treatment to reduce inflammation in the eye (e.g., prednisolone acetate, dexamethasone).
- Pupil-dilating eye drops (cycloplegics): These drops (e.g., cyclopentolate, atropine) help to relieve pain by relaxing the ciliary muscle, prevent the iris from forming adhesions (synechiae) to the lens, and reduce light sensitivity.
- Oral corticosteroids: For severe cases or if there is significant inflammation in other parts of the eye, oral corticosteroids may be prescribed.
- Immunosuppressants: For chronic, severe, or recurrent iritis associated with systemic autoimmune diseases, other immunosuppressive medications may be used to control the underlying condition and reduce inflammation.
- Treatment of underlying cause: If an infection is identified, appropriate antiviral, antibacterial, or antifungal medications will be prescribed. If an autoimmune disease is the cause, managing that condition is crucial.
- Pain relievers: Over-the-counter pain medications (e.g., ibuprofen) can help manage eye pain.
Early diagnosis and prompt treatment are essential to prevent complications such as glaucoma, cataracts, and permanent vision loss. Regular follow-up with the ophthalmologist is necessary to monitor the condition and adjust treatment.
