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CHaPtEr 53 Juvenile Idiopathic Arthritis 729

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on a set schedule as well. Failure to do so and missed eye TREATMENT
involvement may lead to the occurrence of cataracts, glaucoma,
impaired vision, and even blindness. Overview
Despite significant advances in the understanding of the patho-
KEY CONCEPts genesis of JIA, there are currently no curative treatments. JIA
Temporomandibular Joint (TMJ) Arthritis frequently persists into adulthood and may result in significant
morbidity, including physical disability. The objective of treatment
• TMJ arthritis is extremely common, present in up to 80% of children is to prevent disability and preserve normal growth and develop-
with juvenile idiopathic arthritis (JIA). It is typically asymptomatic and ment while providing relief of symptoms and improved quality
thus requires early screening with magnetic resonance imaging (MRI) of life by controlling the inflammatory process. 1
with contrast. Over the past 15 years, remarkable advances have been made
• TMJ arthritis is often active despite therapy with disease-modifying 1
antirheumatic drugs (DMARDs) and biologicals (e.g., methotrexate in the treatment of JIA. Chief among these advances was the
plus tumor necrosis factor [TNF] inhibitors) and thus treatment with advent of targeted biological therapeutic agents (Table 53.2)
intraarticular long-acting corticosteroids or TNF inhibitors may help (Chapter 89). These agents have been shown to be quite beneficial
prevent mandibular growth damage and associated micrognathia and against active disease and are generally well tolerated. The early
1
facial dysmorphology. initiation of biological therapeutic agents may, in fact, alter and
1
improve the subsequent disease course. These new breakthroughs
Another frequently asymptomatic complication of JIA is TMJ have prompted pediatric rheumatologists to “invert the treatment
arthritis. TMJ arthritis in children with JIA has been recognized pyramid,” that is, to rapidly incorporate more effective therapeutic
increasingly in recent years as a joint inflammation leading to agents instead of slowly progressing to them in a stepwise fashion. 1
2
silent destruction and facial deformity despite systemic therapy.
TMJ arthritis is quite common, with 40–80% of all patients with tHEraPEUtiC PriNCiPLEs
2
JIA patients affected. The overall true prevalence is likely closer Early Aggressive Therapy
to the higher range, since not all children with JIA receive TMJ
MRI screening, which frequently reveals synovial thickening (Fig. • Accumulating evidence suggests that early aggressive therapy that
53.3) at disease onset, and premicrognathic arthritis may be includes targeted biological agents near the time of clinical diagnosis
missed. 2,22 The highest rates of TMJ arthritis have been found (during the “window of opportunity”) may improve the future disease
in the extended oligoarticular JIA and RF-negative polyarticular course.
JIA groups, as well as in children with upper extremity and neck
2
involvement, as well as an elevated ESR. Currently, intraarticular In response to the growing number of treatment options for
corticosteroid injection seems to be beneficial in certain cases, JIA and the advent of the biological therapeutics, the American
whereas TMJ arthritis often develops despite systemic use of College of Rheumatology (ACR) issued Recommendations for
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2
methotrexate and TNF inhibitors. TMJ arthritis needs to be the Treatment of JIA in 2011. These recommendations were
recognized early in children with JIA so that it can be treated developed by using a rigorous methodology to produce evidence-
prior to growth disturbance. based and consensus-based guidance that reflected the current
state of the field. The guidelines were updated in 2013 to include
advances in the treatment of sJIA. 25
With new and effective therapies continuing to be introduced
to the therapeutic armamentarium, treatment goals have become
elevated and more stringent. The current goal is to achieve a
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status of clinically inactive disease, that is, the absence of any
significant signs or symptoms of active arthritis. Although cur-
rently this is not possible for all children, until that becomes a
reality, curative therapy for JIA (achievement of inactive disease
status) for as many children as possible remains the goal.
Recent advances in the treatment of adults with inflammatory
arthritis have elucidated some differences in the effectiveness of
specific biological agents for specific forms of arthritis. For
example, many non-TNF inhibitor biologicals, such as abatacept,
rituximab, and tocilizumab, are highly effective in the treatment
of RA but are far less effective in the treatment of ankylosing
spondylitis. In contrast, some of the more recently introduced
biological agents, such as the IL-17 inhibitor secukinumab, appear
effective against ankylosing spondylitis but are likely less effective
for RA. 27
FiG 53.3 Acute and Chronic Temporomandibular Jaw (TMJ) Despite these recent advances, the treatment of JIA is not
Arthritis in a Child With Juvenile Idiopathic Arthritis (JIA). currently strongly influenced by the distinct categories of JIA, with
Synovial thickening and enhancement (long dashed arrow) and the exception of sJIA. For example, there are no specific therapies
mandibular condyle (“C”) flattening with contour irregularity/ currently approved for the treatment of children with psoriatic
erosion (short arrow) are noted in this parasagittal postcontrast arthritis as opposed to RF-negative polyarthritis. Accordingly, the
T1-weighted magnetic resonance imaging (MRI) image. (Courtesy discussion of treatment in this chapter will not detail all categories
of Dr. Dan Young.) of JIA but will focus rather on the “treatment groups” as defined