Scleritis

  SIGNS AND SYMPTOMS
Unlike the mild sensitivity of episcleritis, true scleritis presents with severe, boring ocular pain which may also involve the adjacent head and facial regions. The scleral vessels are significantly dilated, as are the overlying vessels of the episclera and bulbar conjunctiva. The affected eye may be so injected in some cases that the eye actually takes on a deep red, almost purple, hue. This presentation may be sectoral or diffuse.

Patients typically report a gradual onset of the pain and redness, with associated photophobia, tearing and decreased vision. Slip lamp evaluation may reveal scleral nodules (nodular scleritis), peripheral keratitis and secondary uveitis in some instances. In severe cases of necrotizing scleritis, the sclera may become transparent due to chronic inflammation, revealing the underlying dark blue of the choroid.


PATHOPHYSIOLOGY
Scleritis is a primary inflammation of the sclera, which is often (over 50 percent of cases) associated with systemic disease. Among the most common related disorders are rheumatoid arthritis, ankylosing spondylitis, systemic lupus erythematosus, polyarteritis nodosa, Wegener's granulomatosis, herpes zoster virus, gout and syphilis.

Unlike episcleritis, the inflammation characteristic of scleritis has the capacity to spread to other ocular tissues of the anterior segment and/or posterior segment. Consequently, if you do not begin treatment of scleritis immediately, the condition poses the risk of severe visual compromise in the form of cataracts, secondary glaucoma, choroidal or exudative retinal detachment or optic atrophy.

MANAGEMENT
Topical medications alone are generally insufficient in managing scleritis. In addition to cycloplegia (scopolamine 0.25% BID/QID or atropine 1% BID) and a topical steroid, scleritis indicates a systemic anti-inflammatory agents as well. Treat moderate sectoral or diffuse anterior scleritis with oral NSAIDs (e.g., ibuprofen 600mg QID or indomethacin 25mg TID).

If the inflammation is severe or necrotizing, or if non-steroidals alone fail to suppress the inflammation, use a systemic steroid such as oral prednisone 80mg QD for two to three days, then slowly taper to 10 to 20mg daily. It may also be necessary for patients to receive a small maintenance dose for up to one month to control the condition. In rare cases, the patient may require immunosuppressive agents and should be managed by a rheumatologist.

CLINICAL PEARLS

Treated improperly, scleritis can render a great deal of damage to the affected eye.
Be sure to distinguish between this disorder and the less threatening episcleritis.
Occasionally, an atypical presentation of necrotizing scleritis without inflammation may occur; this is known as scleromalacia perforans. In this presentation, the sclera thins significantly in discrete areas, allowing for local outpouchings of the underlying choroid. There is no recognized treatment for this condition.
In all cases of scleritis, always consider the underlying cause to be systemic disease until proven otherwise. Refer patients for a comprehensive medical evaluation, including serology and radiology studies where appropriate. Specific tests may include: complete blood count (CBC) with differential, erythrocyte sedimentation rate (ESR), antinuclear antibody (ANA), HLA-B27, rheumatoid factor (RF), angiotensin-converting enzyme (ACE), fluorescent treponemal antibody absorption (FTA-ABS), lyme titer, chest X-ray and sacroiliac joint films.