Anterior Uveitis / Iridocyclitis – Clinical Features, Complications, Differential Diagnosis, Treatment.
Uveitis - inflammation of the uveal tissue only. However, there is always associated inflammation of the adjacent structures such as retina, vitreous, scleral and cornea.
- Uveitis - inflammation of the uveal tract.
- Anterior uveitis - inflammation of the iris (iritis) and pars plicata of the ciliary body (cyclitis), i.e. iridocyclitis.
- Intermediate uveitis - inflammation of the pars plana part of the ciliary body.
- Posterior uveitis - inflammation of the choroid (choroiditis).
- Endophthalmitis - inflammation of the internal structures of the eye.
- Panophthalmitis - purulent inflammation of all the structures of the eye.
Etiology - iridocyclitis is usually idiopathic. Other causes include immunologic causes such as allergic or hyperergic reaction to bacterial toxins. In some rheumatic disorders it is known to be frequently associated with the expression of specific human leukocyte antigens (HLA) such as HLAB27. Iridocyclitis can also be a symptom of systemic disease such as ankylosing spondylitis, Reiter’s syndrome, sarcoidosis, etc. Infections are less frequent and occur secondary to penetrating trauma or sepsis (bacteria, viruses, mycosis, or parasites).
Symptoms - patients report dull pain in the eye or forehead accompanied by impaired/blurred vision, photophobia, and excessive tearing (epiphora). Exception: juvenile idiopathic arthropathy (JIA) anterior uveitis is painless.
Signs –
- redness of eye with conjunctival circumciliary injection (around the limbus)
- ciliary injection (episcleral and perilimbal vessels may appear blue and red)
- combined injection (conjunctiva is also affected)
- iris is hyperemic (the iris vessels will be visible in a light-colored iris)
- structure appears diffuse and reactive miosis is present
- keratic precipitates (WBC on the corneal endothelium)
- posterior synechiae (inflammatory cells causing adhesions between the lens and iris)
- cells and flare in the anterior chamber (corresponding to WBC and proteins following the breakdown of the blood–iris barrier); seen on the slit lamp.
Investigation - systemic investigation is not usually indicated in the case of a single episode of unilateral acute anterior uveitis. Circumstances that warrant investigation include recurrence, bilateral disease, chronicity, resistance to standard therapy and granulomatous inflammation. Initial baseline investigations, directed by clinical suspicion, may include ESR, full blood count, a serum ACE level, syphilis serology, HLA typing and chest and sacroiliac joint X-rays. Evidence of systemic disease should prompt referral to a physician, for further investigation and management.
Complications -
- Secondary open angle glaucoma with an increase in intraocular pressure.
- Adhesions between the iris and posterior surface of the cornea (anterior synechiae).
- Adhesions between the iris and lens (posterior synechiae).