Normal MRI findings of the knee in patients with clinically active juvenile idiopathic arthritis

Update on the treatment of nonsystemic juvenile idiopathic arthritis including treatment-to-target: is (drug-free) inactive disease already possible?

PURPOSE OF REVIEW

This review concerns the outcome for nonsystemic juvenile idiopathic arthritis (JIA) with emphasis on treatment-to-target (T2T) and treatment strategies aiming at inactive disease by giving an overview of recent articles.

RECENT FINDINGS

More efficacious therapies and treatment strategies/T2T with inactive disease as target, have improved the outcome for JIA significantly. Recent studies regarding treatment strategies have shown 47-68% inactive disease after 1 year. Moreover, probability of attaining inactive disease at least once in the first year seems even higher in recent cohort-studies, reaching 80%, although these studies included relatively high numbers of oligoarticular JIA patients. However, 26-76% of patients flare upon therapy withdrawal and prediction of flares is still difficult.

SUMMARY

Remission can be achieved and sustained in (some) JIA patients, regardless of initial treatment. Cornerstone principles in the management of nonsystemic JIA treatment are early start of DMARD therapy, striving for inactive disease and T2T by close and repeated monitoring of disease activity. T2T and tight control appear to be more important than a specific drug in JIA. Next to inactive disease, it is important that patients/parents are involved in personal targets, like reduction of pain and fatigue. Future studies should focus on predictors (based on imaging-methods or biomarkers) for sustained drug-free remission and flare.

Magnetic resonance imaging of the knee joint in juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is an umbrella term for a group of diseases in children younger than 16 years old lasting six weeks or longer. Synovitis may lead to destructive and irreversible joint changes with subsequent functional impairment. Prompt diagnosis is essential to prevent permanent joint damage and preserve joint functionality. In the course of JIA both the axial and peripheral skeleton may be involved in the inflammatory process, but the knee joint is most frequently affected. New drugs and treatment protocols have forced the need for diagnosis at the earliest possible stage. Magnetic resonance imaging (MRI) allows early detection of lesions and constitutes a superior diagnostic imaging method. Synovitis, tenosynovitis, enthesitis, bursitis, osteitis, cartilage loss, bone cysts, and erosions are lesions diagnosed in JIA, and they can be precisely imaged in MRI. This article aims to present MRI inflammatory features of the knee in children with JIA based on the literature.

Treatment Withdrawal Following Remission in Juvenile Idiopathic Arthritis: A Systematic Review of the Literature

BACKGROUND

Early diagnosis and treatment of juvenile idiopathic arthritis (JIA) with conventional and biologic disease-modifying anti-rheumatic drugs have vastly improved outcomes for children with these diseases. Currently, a large proportion of children with JIA are able to achieve clinical inactive disease and remission. With this success, important questions have arisen about when medications can be stopped and how to balance the risks and benefits of continuing medications versus the potential for flare after stopping.

AIM

The aim was to conduct a systematic review of the available literature to summarize current evidence about medication withdrawal for JIA in remission.

METHODS

We conducted a systematic literature search in PubMed and Embase from 1990 to 2019. References were first screened by title and then independently screened by title and abstract by two authors. A total of 77 original papers were selected for full-text review. Data were extracted from 30 papers on JIA and JIA-associated uveitis, and the quality of the evidence was evaluated using National Institutes of Health (NIH)/National Heart, Lung, and Blood Institute (NHLBI) tools. Studies on biochemical and radiologic biomarkers were also reviewed and summarized.

RESULTS

Most studies investigating treatment withdrawal in JIA have been observational and of poor or fair quality; interpretations of these studies have been limited by differences in study populations, disease and remission durations, the medications withdrawn, approaches to withdrawal, and definitions of disease outcomes. Overall the data suggest that flares are common after stopping JIA medications, particularly biologic medications. Clinical characteristics associated with increased risks of flare have not been consistently identified. Biochemical biomarkers and ultrasound findings have been shown to predict outcomes after stopping medications, but to date, no such predictor has been consistently validated across JIA populations. Studies have also not identified optimal strategies for withdrawing medication for well-controlled JIA. Promising withdrawal strategies include discontinuing methotrexate before biologic medications in children receiving combination therapy, dose reduction for children on biologics, and treat-to-target approaches to withdrawal. These and other strategies require further investigation in larger, high-quality studies.

CONCLUSIONS

The published literature on treatment withdrawal in JIA has varied in design and quality, yielding little conclusive evidence thus far on the management of JIA in remission. Given the importance of this question, international collaborative efforts are underway to study clinical and biologic predictors of successful medication withdrawal in JIA. These efforts may ultimately support the development of personalized approaches to withdrawing medication in children with JIA in remission.

Can quantitative MRI be used in the clinical setting to quantify the impact of intra-articular glucocorticoid injection on synovial disease activity in juvenile idiopathic arthritis?

BACKGROUND

Juvenile idiopathic arthritis (JIA), the most common chronic rheumatic disease of childhood, is characterised by synovitis. Clinical assessments of synovitis are imperfect, relying on composite and indirect measures of disease activity including clinician-reported measures, patient-reported measures and blood markers. Contrast-enhanced MRI is a more sensitive synovitis assessment technique but clinical utility is currently limited by availability and inter-observer variation. Improved quantitative MRI techniques may enable future development of more stringent MRI-defined remission criteria. The objective of this study was to determine the utility and feasibility of quantitative MRI measurement of synovial volume and vascularity in JIA before and twelve weeks after intra-articular glucocorticoid injection (IAGI) of the knee and to assess the acceptability of MRI to participating families.

METHODS

Children and young people with JIA and a new episode of knee synovitis requiring IAGI were recruited from the Great North Children's Hospital in Newcastle upon Tyne. Quantitative contrast-enhanced MRI was performed prior to and twelve weeks after IAGI, in addition to standard clinical assessment tools, including the three-variable clinical juvenile arthritis disease activity score (cJADAS) and active joint count.

RESULTS

Eleven young people (5 male, median age 13 years, range 7-16) with JIA knee flare were recruited and 10 completed follow-up assessment. Following IAGI, the median (interquartile range) cJADAS improved from 8.5 (2.7) to 1.6 (3.9), whilst the median synovial volume improved from 38.5cm³ (82.1cm³) to 0.0cm³ (0.2cm³). Six patients presented with frank synovitis outside normal limits on routine MRI reporting. A further three had baseline MRI reports within normal limits but the quantitative measurements identified measurable synovial uptake. Post-IAGI quantitative measurements highlighted significant improvements in 9 patients.

CONCLUSIONS

IAGI led to a marked reduction in synovial volume, with quantitative MRI identifying more patients with an improved synovial volume than routine qualitative clinical reporting. Improvements in cJADAS scores were more variable with the patient/parent global assessment component contributing most to the scores. Further work is indicated, exploring the utility of quantitative MRI in the assessment of less accessible joints and comparing the impact of different treatment modalities.