Synovial and inflammatory diseases in childhood: role of new imaging modalities in the assessment of patients with juvenile idiopathic arthritis

Osteochondral lesions in children with juvenile idiopathic arthritis

BACKGROUND

Joint pain and swelling are typical symptoms in children with juvenile idiopathic arthritis (JIA) and these are often related to inflammation of the joint. Juvenile osteochondritis dissecans (JOCD), that is separation of a bone-cartilage segment from the articular surface, can manifest with similar symptoms.

FINDINGS

We studied thirteen cases of osteochondritis dissecans lesions (OCD) in children with JIA. There were nine girls and four boys with a mean age of 6.5 (2-12) years at the time of diagnosis of JIA. Mean time between diagnosis of JIA and manifestation of OCD was 5.5 (1-11) years. Indications for MRI were the presence of pain or discomfort in the joint, despite otherwise effective treatment, with no evidence from ultrasound examination of any obvious signs of active inflammation. The most common location of osteochondral lesion was the knee, although the ankle joint was affected in one case. Five patients had lesions in both knees. Operative treatment was needed in eight cases (joints).

CONCLUSIONS

Pain, and minor dysfunction of the joint are common complaints of children suffering from JIA. Earlier research has discounted the possibility of children who were not athletes presenting with this condition. However, this study demonstrates that these lesions also seem to be relatively common in patients with JIA. When there is no sign of inflammation, the possibility of OCD must therefore be considered in these children.

Juvenile idiopathic arthritis and athletic participation: are we adequately preparing for sports integration?

Children with juvenile idiopathic arthritis (JIA) now have well-controlled disease due to improved therapies and management strategies. Children with JIA are more active than in the past and often participate in dynamic, high-loading sports. Standard measures of disease control include examination findings, laboratory values, and patient-directed surveys. However, these standards do not address the subtle deficits in biomechanics and neuromuscular control, which could place affected joints at higher risk for injury. Currently, there are limited evidence-based guidelines to structure conditioning recommendations as to the fitness and mechanics needed to provide safe integration into sports in this population; therefore, tools that objectively measure function with high accuracy and precision may be warranted. Previous work using 3-dimensional motion analysis demonstrated usefulness in guiding physical therapy treatment to correct these deficits. The use of a multidisciplinary team, including physical therapy, rheumatology, and sports medicine, is crucial for preparing these children to return to play. We suggest that the child transition into a sport preparatory-conditioning program to address any underlying deficits. A pediatric exercise specialist who is sensitive to the needs of this population can work with a physical therapist to then appropriately integrate the child safely into sport. Encouraging an active lifestyle is vital to the management of JIA and does not worsen the symptoms associated with childhood arthritis.

Juvenile idiopathic arthritis: management and therapeutic options

THE GOALS OF TREATMENT FOR JUVENILE IDIOPATHIC ARTHRITIS (JIA) INCLUDE: suppression of inflammation, achievement of remission, relief of pain, maintenance of function and doing so with minimal toxicity. Important discoveries over the past 10-15 years have led to more targeted treatments for children with JIA. The International League of Associations for Rheumatology (ILAR) classification system for childhood arthritides, better assessment tools for clinical response, improved definitions of remission, new imaging techniques and evidence in gene expression profiling have all contributed to the development of more targeted treatments. Nonsteroidal anti-inflammatory agents still have a role in mild disease and intra-articular steroid injections continue to be used most commonly in patients with oligoarticular JIA. Disease-modifying agents such as methotrexate have demonstrated efficacy and safety; however, in many patients, the disease remains active despite this treatment. These children now receive more targeted treatment including the tumor necrosis factor alpha (TNFα) inhibitors, interleukin-1 blockade, interleukin-6 blockade, selective costimulation modulators and selective B-cell blockade. The biologic targeted therapies have changed the strategy in which we treat our children with JIA; however, there remains much to be learned about the long-term effects and safety of these medicines.

Comparison of ultrasonography with Doppler and MRI for assessment of disease activity in juvenile idiopathic arthritis: a pilot study

BACKGROUND

In juvenile idiopathic arthritis (JIA), the trend towards early therapeutic intervention and the development of new highly effective treatments have increased the need for sensitive and specific imaging. Numerous studies have demonstrated the important role of MRI and US in adult rheumatology. However, investigations of imaging in JIA are rare, and no previous study has been comparing MRI with Doppler ultrasonography (US) for assessment of arthritis. The aim of the present study was to compare the two imaging methods regarding their usefulness for evaluating disease activity in JIA, and to compare the results with those obtained in healthy controls.

METHODS

In 10 JIA patients (median age 14 years, range 11-18), 11 joints (six wrists, three knees, two ankles) with arthritis were assessed by color Doppler US and MRI. The same imaging modalities were used to evaluate eight joints (three wrists, three knees, two ankles) in six healthy age- and sex-matched controls. The US examinations of both the patients and controls were compared with the MRI findings.

RESULTS

In 10 JIA patients, US detected synovial hypertrophy in 22 areas of 11 joints, 86% of which had synovial hyperemia, and MRI revealed synovitis in 36 areas of the same 11 joints. Erosions were identified by US in two areas of two joints and by MRI in six areas of four joints. Effusion was shown by US in nine areas of six joints and by MRI in 17 areas of five joints. MRI detected juxta-articular bone marrow edema in 16 areas of eight joints.

CONCLUSIONS

The results of this pilot study indicate that both MRI and US provide valuable imaging information on disease activity in JIA. Importantly, the two techniques seem to complement each other and give partly different information. Although MRI is considered to be the reference standard for advanced imaging in adult rheumatology, US seems to provide useful imaging information that could make it an option in daily clinical practice, in JIA as well as in adult rheumatology. However, the current work represents a pilot study, and thus our results need to be confirmed in a larger prospective clinical investigation.

MR imaging assessment of inflammatory, crystalline-induced, and infectious arthritides

The role of magnetic resonance imaging in evaluating patients with inflammatory arthritides has evolved with the recent introduction of drugs capable of modifying disease activity and natural history. In conditions like rheumatoid arthritis, active synovitis and bone marrow inflammation precede and predict bone and cartilage erosion. These imaging findings identify patients who can be treated early and aggressively to prevent future morbidity. Similarly, in gout and other crystalline disorders, specific diagnosis aided by imaging may lead to earlier medical and surgical management. Infected joints need the most rapid identification to institute immediate therapy and prevent irreversible cartilage destruction.

Combined pre-injection wrist and ankle MRI protocol and steroid joint injections in juvenile idiopathic arthritis

Precise localization of affected compartments of the wrist and ankle in children with an established diagnosis of juvenile idiopathic arthritis (JIA) is clinically challenging. The purpose of this paper is to describe our experience utilizing a pre-injection MRI protocol of the wrist and ankle for localizing disease activity followed by fluoroscopically guided joint injections in children with JIA.

Detection of Active Disease in Juvenile Idiopathic Arthritis: Sensitivity and Specificity of the Physical Examination vs Ultrasound

Objective.

To determine sensitivity and specificity of the physical examination (PE) for identifying synovitis in the knee and ankle joints of children with juvenile idiopathic arthritis (JIA), and to identify cases in which ultrasound (US) screening augments the PE.

Methods.

Nineteen patients with JIA were referred for US. Both knees and ankles were examined using US with and without power Doppler. Active arthritis on PE was defined as (1) non-bony swelling or (2) limitation of motion with either pain on motion or tenderness to palpation. Active arthritis on US was defined as synovial hyperplasia, effusion, or increased vascularity on power Doppler scan.

Results.

There was agreement between US and PE in 75% of cases. PE was 64% sensitive and 86% specific for identifying active arthritis. PE was 100% specific if (1) the patient was positive for both PE criteria or (2) if arthritis was present on PE in the knees. When the PE was negative and the US was positive, 21.4% developed active disease on PE within 6 months. In cases where the PE was positive and US was negative, the joint involved was most often the ankle and frequently the subtalar joint.

Conclusion.

PE is neither highly sensitive nor specific for identifying active synovitis when compared to US, and screening with US can identify subclinical disease. In joints with both non-bony swelling and limitation of motion with pain on motion or tenderness, and in the knee joint, little additional information is gained by US. This has implications for classification and treatment of JIA.

Musculoskeletal ultrasound in pediatric rheumatology

Although musculoskeletal ultrasound (MSUS) has emerged as an indispensible tool among physicians involved in musculoskeletal medicine in the last two decades, only recently has it become more attractive to pediatric rheumatologists. Thereafter, the use of MSUS in pediatric rheumatology has started to increase. Yet, an ever-growing body of literature shows parity and even superiority of MSUS when compared to physical examination and other imaging modalities.MSUS is suitable for examination of children of all ages and it has certain advantages over other imaging modalities; as it is cheaper, mobile, instantly accessible bedside, easy to combine with clinical assessment (interactivity) and non-invasive. It does not require sedation, which facilitates repetitive examinations. Assessment of multiple locations is possible during the same session. Agitation is rarely a problem and small children can be seated in their parents' lap or they can even play while being examined.

Ultrasonography and color Doppler of proximal gluteal enthesitis in juvenile idiopathic arthritis: a descriptive study

BACKGROUND

The presence of enthesitis (insertional inflammation) in patients with juvenile idiopathic arthritis (JIA) is difficult to establish clinically and may influence classification and treatment of the disease. We used ultrasonography (US) and color Doppler (CD) imaging to detect enthesitis at the small and deep-seated proximal insertion of the gluteus medius fascia on the posterior iliac crest where clinical diagnosis is difficult. The findings in JIA patients were compared with those obtained in healthy controls and with the patients' MRI results.

METHODS

Seventy-six proximal gluteus medius insertions were studied clinically (tenderness to palpation of the posterior iliac crest) and by US and CD (echogenicity, thickness, hyperemia) in 38 patients with JIA and in 38 healthy controls, respectively (median age 13 years, range 7-18 years). In addition, an additional MRI examination of the sacroiliac joints and iliac crests was performed in all patients.

RESULTS

In patients with focal, palpable tenderness, US detected decreased echogenicity of the entheses in 53% of the iliac crests (bilateral in 37% and unilateral in 32%). US also revealed significantly thicker entheses in JIA patients compared to healthy controls (p < 0.003 left side, p < 0.001 right side). There was no significant difference in thickness between the left and right sides in individual subjects. Hyperemia was detected by CD in 37% (28/76) of the iliac crests and by contrast-enhanced MRI in 12% (6/50).

CONCLUSIONS

According to US, the gluteus medius insertion was thicker in JIA patients than in controls, and it was hypoechoic (enthesitis) in about half of the patients. These findings may represent chronic, inactive disease in some of the patients, because there was only limited Doppler flow and MRI contrast enhancement. The present study indicates that US can be useful as an adjunct to clinical examination for improved assessment of enthesitis in JIA. This may influence disease classification, ambition to treat, and choice of treatment regimen.

Juvenile idiopathic arthritis

Juvenile idiopathic arthritis is a heterogeneous group of diseases characterised by arthritis of unknown origin with onset before age of 16 years. Pivotal studies in the past 5 years have led to substantial progress in various areas, ranging from disease classification to new treatments. Gene expression profiling studies have identified different immune mechanisms in distinct subtypes of the disease, and can help to redefine disease classification criteria. Moreover, immunological studies have shown that systemic juvenile idiopathic arthritis is an acquired autoinflammatory disease, and have led to successful studies of both interleukin-1 and interleukin-6 blockade. In other forms of the disease, synovial inflammation is the consequence of a disturbed balance between proinflammatory effector cells (such as T-helper-17 cells), and anti-inflammatory regulatory cells (such as FOXP3-positive regulatory T cells). Moreover, specific soluble biomarkers (S100 proteins) can guide individual treatment. Altogether these new developments in genetics, immunology, and imaging are instrumental to better define, classify, and treat patients with juvenile idiopathic arthritis.

Juvenile idiopathic arthritis: new insights into classification, measures of outcome, and pharmacotherapy

Significant advances have taken place in recent years in our understanding of the aetiopathogenesis, management, and clinical outcome of juvenile idiopathic arthritis (JIA). Fundamental to this advancement has been international collaborative efforts of the clinical scientific community and all those involved in the multidisciplinary care of children and young people with JIA. A key factor has been facing the challenge of developing a robust classification system for JIA, a clinically very heterogeneous group of conditions. JIA illustrates the necessity of disease classification to enable scientific progress but also the iterative and evolving process this entails. What is emerging is the imperative to improve our understanding of the biologic and genetic basis of JIA to underpin classification systems. Growing emphasis is centered on improved holistic care and outcome of children and young people with JIA. The expectation of patients, their families, and clinicians is the goal of inactive disease, remission off treatment, and the health and psychosocial well-being of young people emerging into adulthood. Validated tools that reflect these challenges are being developed, including those measuring disease improvement, flare, remission and minimal disease activity, health-related quality of life, and composite scores of activity and damage. Clinical research networks have driven success in developing an evidence-base for the treatment of JIA. Randomized comparative trials have demonstrated the benefit of early use of intra-articular corticosteroid injections, and the importance of methotrexate as the first-line, disease-modifying antirheumatic drug in JIA. The introduction of biologic therapies has opened a major new epoch in the medical management of JIA, with recent trials published on etanercept, infliximab, adalimumab, abatacept, tocilizumab, and anakinra. This review focuses on recent advances in JIA, especially developments in its classification, validation of appropriate measures of holistic outcome, and the specific contribution of established and newer pharmacologic agents available for treating children and young people.

Paediatric musculoskeletal US beyond the hip joint

US is a technique particularly suited to the investigation of musculoskeletal disorders in children and adolescents. This review paper describes a range of clinical settings beyond the hip joint where US has a significant role to play, including sports injuries, infectious diseases, inflammatory and degenerative conditions, congenital and developmental disorders, acute trauma of bone and joints, and peripheral nerve injuries. In some circumstances, US can be regarded as the most effective means of diagnostic imaging, whereas in other instances, it is an alternative or supplement to other more comprehensive imaging modalities, like MRI and CT. Although MRI offers superior soft-tissue contrast resolution, US is low-cost, non-invasive and has higher spatial resolution and real-time capability for the assessment of musculoskeletal structures during joint movement and stress manoeuvres.

Ultrasonography and color Doppler in juvenile idiopathic arthritis: diagnosis and follow-up of ultrasound-guided steroid injection in the ankle region. A descriptive interventional study

BACKGROUND

The ankle region is frequently involved in juvenile idiopathic arthritis (JIA) but difficult to examine clinically due to its anatomical complexity. The aim of the study was to evaluate the role of ultrasonography (US) of the ankle and midfoot (ankle region) in JIA. Doppler-US detected synovial hypertrophy, effusion and hyperemia and US was used for guidance of steroid injection and to assess treatment efficacy.

METHODS

Forty swollen ankles regions were studied in 30 patients (median age 6.5 years, range 1-16 years) with JIA. All patients were assessed clinically, by US (synovial hypertrophy, effusion) and by color Doppler (synovial hyperemia) before and 4 weeks after US-guided steroid injection.

RESULTS

US detected 121 compartments with active disease (joints, tendon sheaths and 1 ganglion cyst). Multiple compartments were involved in 80% of the ankle regions. The talo-crural joint, posterior subtalar joint, midfoot joints and tendon sheaths were affected in 78%, 65%, 30% and 55% respectively. Fifty active tendon sheaths were detected, and multiple tendons were involved in 12 of the ankles. US-guidance allowed accurate placement of the corticosteroid in all 85 injected compartments, with a low rate of subcutaneous atrophy (4,7%). Normalization or regression of synovial hypertrophy was obtained in 89%, and normalization of synovial hyperemia in 89%. Clinical resolution of active arthritis was noted in 72% of the ankles.

CONCLUSIONS

US enabled exact anatomical location of synovial inflammation in the ankle region of JIA patients. The talo-crural joint was not always involved. Disease was frequently found in compartments difficult to evaluate clinically. US enabled exact guidance of steroid injections, gave a low rate of subcutaneous atrophy and was proved valuable for follow-up examinations. Normalization or regression of synovial hypertrophy and hyperemia was achieved in most cases, which supports the notion that US is an important tool in the management of ankle involvement in JIA.

Serum levels of osteoprotegerin and receptor activator of nuclear factor -κB ligand in children with early juvenile idiopathic arthritis: a 2-year prospective controlled study

BACKGROUND

The clinical relevance of observations of serum levels of osteoprotegerin (OPG) and receptor activator of nuclear factor -κB ligand (RANKL) in juvenile idiopathic arthritis (JIA) is not clear. To elucidate the potential role of OPG and RANKL in JIA we determined serum levels of OPG and RANKL in patients with early JIA compared to healthy children, and prospectively explored changes in relation to radiographic score, bone and lean mass, severity of the disease, and treatment.

METHODS

Ninety children with early oligoarticular or polyarticular JIA (ages 6-18 years; mean disease duration 19.4 months) and 90 healthy children individually matched for age, sex, race, and county of residence, were examined at baseline and 2-year follow-up. OPG and RANKL were quantified by enzyme-immunoassay. Data were analyzed with the use of t-tests, ANOVA, and multiple regression analyses.

RESULTS

Serum OPG was significantly lower in patients than controls at baseline, and there was a trend towards higher RANKL and a lower OPG/RANKL ratio. Patients with polyarthritis had significantly higher increments in RANKL from baseline to follow-up, compared to patients with oligoarthritis. RANKL was a significant negative predictor for increments in total body lean mass. Patients who were receiving corticosteroids (CS) or disease-modifying antirheumatic drugs (DMARDs) at follow-up had higher OPG/RANKL ratio compared with patients who did not receive this medication.

CONCLUSIONS

The data supports that levels of OPG are lower in patients with JIA compared to healthy children, and higher levels of RANKL is associated with more serious disease. RANKL was a significant negative predictor of lean mass in patients with JIA. The OPG/RANKL ratio was higher in patients on DMARDs or CS treatment.