Uveitis
Uveitis is an inflammation of the uvea, which is the middle layer of the eye. The uvea consists of the iris (the colored part of the eye), ciliary body (which produces aqueous humor), and the choroid (the layer of blood vessels beneath the retina). Uveitis can affect one or more parts of the uvea and can cause a range of symptoms, from mild irritation to severe vision loss.
Causes of Uveitis
Uveitis can have several potential causes, including:
- Autoimmune Diseases:
- Conditions like rheumatoid arthritis, ankylosing spondylitis, psoriasis, lupus, and sarcoidosis can lead to uveitis as part of systemic inflammation.
- Infections:
- Bacterial, viral, fungal, and parasitic infections can lead to uveitis. Some examples include tuberculosis, syphilis, herpes simplex virus, cytomegalovirus (CMV), and toxoplasmosis.
- Trauma or Injury:
- Physical trauma to the eye or previous eye surgery may trigger uveitis.
- Medications:
- Certain medications, such as bisphosphonates and immune system modulators, can contribute to inflammation of the uvea.
- Genetic Factors:
- Some individuals may have a genetic predisposition to uveitis, particularly if they have a family history of autoimmune or inflammatory diseases.
- Unknown Causes:
- In some cases, no specific cause can be identified, and the condition is considered idiopathic (without a known origin).
Types of Uveitis
Uveitis can be classified based on the part of the uvea that is affected:
- Anterior Uveitis (also called iritis):
- This is the most common form of uveitis, affecting the iris and sometimes the ciliary body. It often causes symptoms like pain, redness, and sensitivity to light (photophobia).
- Intermediate Uveitis:
- This affects the ciliary body and the vitreous (the gel-like substance inside the eye). It can cause blurred vision and floaters (small spots or lines that move in the field of vision).
- Posterior Uveitis:
- This affects the choroid and retina at the back of the eye. It can lead to symptoms such as vision loss, blurred vision, and light flashes.
- Panuveitis:
- This type involves inflammation of all parts of the uvea (anterior, intermediate, and posterior). It may cause severe symptoms and complications.
Symptoms of Uveitis
The symptoms of uveitis can vary depending on the type and severity of inflammation but commonly include:
- Eye redness: Often more pronounced in anterior uveitis.
- Pain or tenderness in the eye: Especially in the front of the eye.
- Blurred vision: Due to inflammation affecting the retina or vitreous.
- Photophobia: Sensitivity to light.
- Floaters: The appearance of spots or shapes moving across the field of vision.
- Decreased vision: In more severe cases, particularly in posterior uveitis.
- Tearing or watery eyes: Sometimes, there may be excessive tearing.
Diagnosis of Uveitis
Diagnosing uveitis typically involves a comprehensive eye examination by an eye specialist (ophthalmologist), who will perform several tests to evaluate the extent and type of inflammation, including:
- Slit-lamp Examination:
- This helps the doctor examine the anterior part of the eye for signs of inflammation, including redness, swelling, and cellular activity in the aqueous humor (the fluid between the lens and cornea).
- Fundus Exam:
- A thorough examination of the retina and the back of the eye to check for signs of posterior uveitis.
- Blood Tests:
- These may be conducted to check for underlying systemic conditions or infections that could be causing the uveitis, such as autoimmune diseases or infections.
- Imaging:
- Techniques like optical coherence tomography (OCT) or fluorescein angiography may be used to assess retinal involvement.
Treatment of Uveitis
The treatment of uveitis focuses on reducing inflammation, managing symptoms, and preventing complications that could lead to vision loss. Treatment options may include:
- Corticosteroids:
- These are the most common treatment to reduce inflammation. They can be administered as eye drops (for anterior uveitis), oral tablets, or injected directly into the eye or around the eye (in severe cases).
- Immunosuppressive Drugs:
- If uveitis is associated with autoimmune diseases or if corticosteroids are not effective, immunosuppressive medications like methotrexate, cyclophosphamide, or azathioprine may be used to control the immune response.
- Antibiotics or Antiviral Drugs:
- If an infection is the underlying cause of uveitis, appropriate treatments such as antibiotics, antivirals, or antifungals will be prescribed.
- Biologic Agents:
- In some cases, biologic drugs (such as TNF inhibitors) may be used for autoimmune-related uveitis, especially if conventional treatments are not effective.
- Pain Relief:
- Nonsteroidal anti-inflammatory drugs (NSAIDs) may be used to manage pain and inflammation.
- Surgery:
- In rare cases, surgery may be needed, such as a vitrectomy to remove the inflamed vitreous or if there is retinal damage.
Complications of Uveitis
If left untreated or poorly managed, uveitis can lead to serious complications, including:
- Glaucoma: Increased pressure in the eye that can damage the optic nerve and lead to permanent vision loss.
- Cataracts: Clouding of the eye's lens, often as a side effect of corticosteroid treatment.
- Retinal damage: Inflammation at the back of the eye can lead to retinal scars, retinal detachment, or damage to the macula, resulting in permanent vision loss.
- Vision impairment: Severe or prolonged uveitis can lead to irreversible damage to vision.
Prognosis
With prompt diagnosis and treatment, many individuals with uveitis can manage their symptoms and avoid serious complications. However, the outcome can vary depending on the underlying cause, the type of uveitis, and the effectiveness of treatment. Chronic or recurrent uveitis may require ongoing management to prevent flare-ups and preserve vision.
