UveitisDz

Synonyms: Iritis, iridocyclitis, anterior uveitis, posterior uveitis, chorioretinitis.

ICD9 Code: Acute Uveitis  364.0: Chronic Uveitis 364.10
ICD10  Code: Acute iridocyclitis H20.0 0: Chronic iridocyclitis, bilateral  H20.13

Definition: Uveitis refers to any inflammatory disease that involves the uveal tract (or midportion of the eye, which includes the iris, ciliary body, and choroid layer). Between 20% and 40% of patients with uveitis have an associated systemic disease. Anterior uveitis may involve the iris (iritis) or iris and ciliary body (iridocyclitis) and may be associated with HLA-B27 and inflammatory joint disease (e.g., AS, reactive arthritis, sarcoidosis). Posterior uveitis may involve the choroid (choroiditis), retina (retinitis), or vitreous near the macula and optic nerve. Posterior uveitis is commonly associated with infection. Sarcoidosis and Behçet’s syndrome are unique conditions that may involve either the anterior or posterior chamber.

Etiology: Uveitis may be isolated and idiopathic or result from a variety of infectious or immunologic conditions (Table 48). An association is seen with HLA-B27 positivity in nearly 60% of acute anterior uveitis patients.

Pathology: Common findings include corneal edema, keratitic precipitates, and inflammatory changes in the anterior chamber. Posterior uveitis may show vitreal exudates, focal chorioretinal infiltrates, retinal vasculitis, or macular edema. Synechiae are fibrous scars (adhesions) that can be seen between the iris and lens or iris and cornea.

Demographics: Anterior uveitis is four times more prevalent than posterior uveitis. The incidence of anterior uveitis is 8.2 cases per 100,000 annually. Males and females are equally affected, unless the individual is HLA-B27 positive, wherein males predominate.

Cardinal Findings: Acute anterior uveitis usually has an acute onset, with deep eye pain, photophobia, and decreased visual acuity, with or without conjunctival injection. Corneal opacities (clouding) may be seen because of the inflammatory infiltrate in the anterior chamber. Synechiae may form between the lens and iris. Episodic or recurrent disease is not uncommon. Unilateral presentations are more common than bilateral. Bilateral uveitis has a greater association with systemic features and interstitial nephritis. Half of patients with acute anterior uveitis are positive for HLA-B27. HLA-B27-positive patients with uveitis are more likely to be male with younger age at onset, more synechiae, complications, and frequent association with an SpA. Chronic anterior uveitis is far less frequent and is seen in as many as 20% of children with juvenile arthritis.

Posterior uveitis tends to have an insidious onset with less discomfort (rather than pain), decreased visual acuity, and floating spots, usually affecting both eyes.

Complications: Permanent visual loss is a grave complication that may result from precipitates on the cornea or lens, secondary glaucoma, obstructive synechiae, cataracts, or, rarely, vasculitis, vascular occlusion, or retinal infarction. Topical ocular steroid therapy may be complicated by increased intraocular pressure and cataracts.

Diagnostic Tests: No specific laboratory test can diagnose uveitis. Investigations are often necessary to identify an underlying disorder (e.g., CBC, creatinine, urinalysis, ANA, ESR, VDRL, purified protein derivative, HLA-B27).

Imaging: Imaging procedures are not necessary to diagnose uveitis. In those with low back pain, radiographs may disclose evidence of sacroiliitis. Chest radiographs may be helpful in the diagnosis of suspected systemic disorders such as tuberculosis, sarcoidosis, or lymphoma.

Keys to Diagnosis: Patients suspected of having uveitis should have a slit lamp examination by an ophthalmologist.

Differential Diagnosis: Conjunctivitis, episcleritis, scleritis, keratitis, and acute angle-closure glaucoma must be differentiated.

Therapy: Most patients respond well to topical corticosteroids and mydriatics (i.e., homatropine hydrobromide 2% ophthalmic solution b.i.d.) that may retard development of synechiae. Prednisolone acetate 1% ophthalmic suspension is often given 2 drops every hour initially, then tapered to four times daily dosing. Chronic anterior uveitis may be more difficult to treat and may require systemic therapy. Posterior uveitis (not related to infection) may also require systemic therapy when vision is impaired. Infectious etiologies should be addressed with the appropriate antiinfective agent. Uveitis that is refractory to topical steroids may require systemic steroids, azathioprine, cyclosporine, chlorambucil, cyclophosphamide, or MTX.

BIBLIOGRAPHY

Petty RE, Smith JR, Rosenbaum JT. Arthritis and uveitis in children. A pediatric rheumatology perspective. Am J Ophthalmol 2003;135:879–884.PMID:12788129

Rosenbaum JT. Uveitis: an internists view. Arch Intern Med 1989;149:1173–1176.PMID:2719509

Tay-Dearney ML, Schwam BL, Lowder C, et al. Clinical features and associated systemic diseases of HLA-B27 uveitis. Am J Ophthalmol 1996;121:47–56. PMID:8554080