Anterior Uveitis
Juvenile Idiopathic Arthritis
Nomenclature
Juvenile idiopathic arthritis (JIA) (formerly chronic arthritis or juvenile rheumatoid arthritis) is defined as arthritis of at least 6 weeks’ duration without any identifiable cause in children younger than 16 years. The subtypes of JIA are listed in Table 24-2.
Table 24-2
Occurrence of uveitis in JIA
JIA is the most common identifiable etiology of childhood anterior uveitis. Overall, the prevalence of uveitis in JIA varies from 2% to 34%. The subtypes of JIA that are particularly associated with uveitis are oligoarthritis, rheumatoid factor (RF)–negative polyarthritis, psoriatic arthritis, and enthesitisrelated arthritis. Uveitis almost never occurs in children with systemic arthritis and is very rare in those with RF-positive polyarthritis.
Oligoarthritis is the most frequent type of chronic arthritis in children in North America and Europe. Oligoarthritis occurs predominantly in young girls and affects 4 or fewer joints during the first 6 months of the disease. Anterior uveitis or iritis is most likely to occur with this type of arthritis. Uveitis has been reported in 10%–30% of children with oligoarthritis. Laboratory markers include a high prevalence of antinuclear antibodies (ANA). RF is almost always absent. HLA associations
include HLA-A2, HLA-DR5, HLA-DR8, HLA-DR11, and HLA-DP2.1.
Children with RF-negative polyarthritis have more than 4 inflamed joints during the first 6 months of the disease. This disease is more common in girls, and its mean age of onset is later than in children with oligoarthritis. Uveitis occurs in about 10% of these children. ANA positivity may be present, but RF is absent. Strong HLA associations have not been consistently documented.
The pathogenesis of the anterior uveitis associated with JIA is unknown, but it is likely to have an immunologic basis. The risk for development of uveitis is highest during the first 4 years after diagnosis of JIA. Among patients with JIA in whom uveitis develops, 90% of uveitis cases develop within 7 years of the onset of arthritis. Occasionally, uveitis is diagnosed before or at the onset of joint symptoms. Unfortunately, these patients often have a poorer prognosis because the initially asymptomatic nature of their ocular inflammation often delays diagnosis. A shorter interval between the onsets of arthritis and uveitis is also associated with a more aggressive course.
JIA-associated uveitis is usually bilateral and nongranulomatous with fine to medium-sized keratic precipitates, but a minority of children, especially African Americans, may have granulomatous precipitates. Chronic inflammation may produce band keratopathy (Fig 24-1), posterior synechiae, ciliary membrane formation, hypotony, cataract, glaucoma, and phthisis. Vitritis and macular edema occur infrequently.
Figure 24-1 Slit-lamp photograph of a patient with uveitis associated with juvenile idiopathic arthritis. As is typical, the conjunctiva is “white.” Band keratopathy is present. (Courtesy of Amy Hutchinson, MD.)
Recognition of the importance of screening for uveitis in children with JIA has resulted in an improved prognosis for this disorder. However, visual impairment has been reported in up to 40% of
children with JIA-associated uveitis, and blindness may occur in as many as 10% of affected eyes. Screening guidelines continue to undergo revision but are based on 4 factors that are associated with an increased risk of uveitis:
1.category of arthritis
2.age at onset of arthritis
3.presence of ANA positivity
4.duration of the disease
Table 24-3 outlines the eye examination schedule for the first 4 years after diagnosis of JIA, as recommended by the American Academy of Pediatrics. After 4 years, the eye examinations become less frequent. Although female gender is associated with a higher incidence of uveitis, this factor is not incorporated into the guidelines. Initial ocular examination should occur within 6 weeks of diagnosis (see reference below).
Table 24-3
Other arthritic diseases of childhood may also be associated with uveitis. Psoriatic arthritis is uncommon, but it may be underdiagnosed because the findings can resemble those of oligoarthritis and RF-negative polyarthritis. The diagnosis is suggested by the presence of arthritis and 2 of the following findings: nail changes (pitting or onycholysis), dactylitis, or a history of psoriasis in a first-degree relative. Insidious and chronic anterior uveitis, usually bilateral, is seen in 10% of affected children.
Enthesitis-related arthritis is a chronic arthritis that is associated with inflammation of entheses, which are the sites where the ligaments, tendons, fasciae, and capsules attach to the bone. This form of childhood arthritis, which has also been referred to as juvenile ankylosing spondylitis, usually has its onset at age 8–10 years and is more common in males. The uveitis is acute, symptomatic, and unilateral, but both eyes may be affected at different times. Most patients are HLA-B27–positive, and lumbosacral spine disease and sacroiliitis eventually develop in many.
Cassidy J, Kivlin J, Lindsley C, et al; Section on Rheumatology; Section on Ophthalmology. Ophthalmologic examinations in children with juvenile rheumatoid arthritis. Pediatrics. 2006;117(5):1843–1845.
Tubulointerstitial Nephritis and Uveitis Syndrome
Tubulointerstitial nephritis and uveitis (TINU) syndrome is kidney disease associated with chronic or recurrent anterior uveitis in children. The etiology is unknown but may be associated with HLADRB1. The median age of onset is 15 years; early studies indicate that it is more common in females, while more recent studies indicate that it is more common in males. The renal disease is characterized by low-grade fever, fatigue, pallor, and weight loss. Elevated levels of β2-microglobulin may be present in the urine. The uveitis is usually bilateral and may occur before, simultaneously with, or after the renal disease. Prognosis is generally good, although long-term follow-up is required because the inflammation may recur.
Mackensen F, Billing H. Tubulointerstitial nephritis and uveitis syndrome. Curr Opin Ophthalmol. 2009;20(6):525–531.