Nomenclature and classification in chronic childhood arthritis: time for a change?

How common is remission in rheumatoid factor-positive juvenile idiopathic arthritis patients? The multicenter Pediatric Rheumatology Academy (PeRA) research group experience

OBJECTIVE

Rheumatoid factor (RF)-positive polyarthritis is the least common type of juvenile idiopathic arthritis (JIA). Functional disability in RF-positive polyarthritis patients is much more severe than in patients with other subtypes; but data on this subtype alone is limited. This study aimed to analyze clinical features, long-term follow-up, treatment response, and remission status in a large multicenter cohort of RF-positive polyarthritis patients.

METHODS

This retrospective study included RF-positive polyarthritis patients that were followed up for ≥ 6 months between 2017 and 2022 by the Pediatric Rheumatology Academy (PeRA)-Research Group (RG). Data on patient demographics, clinical and laboratory characteristics were obtained from medical charts. JIA treatments and duration of treatment were also recorded. The patients were divided into 2 groups based on methotrexate (MTX) response, as follows: group 1: MTX responsive, group 2: MTX unresponsive. Clinical and laboratory findings were compared between the 2 groups.

RESULTS

The study included 56 (45 female and 11 male) patients. The median age at onset of RF-positive polyarthritis was 13.2 years [(interquartile range) (IQR): 9.0-15.0 years] and the median duration of follow-up was 41.5 months (IQR: 19.5-75.7 months). Symmetrical arthritis affecting the metacarpophalangeal and proximal interphalangeal joints of the hands was commonly observed. Subcutaneous MTX was the preferred initial treatment; however, it was ineffective in 39 (69.6%) of the patients. Of 25 patients followed for 24 months, 56% still had active disease at 24 months.

CONCLUSION

During 2 years of treatment, 44% of RF-positive polyarthritis patients have inactive disease, and they should be considered as a distinct and important clinical entity requiring aggressive and early treatment.

Moving from nature to nurture: a systematic review and meta-analysis of environmental factors associated with juvenile idiopathic arthritis

Objectives

JIA is the most common paediatric rheumatic disease, thought to be influenced by both genetics and the environment. Identifying environmental factors associated with disease risk will improve knowledge of disease mechanism and ultimately benefit patients. This review aimed to collate and synthesize the current evidence of environmental factors associated with JIA.

Methods

Four databases (MEDLINE, Embase, Web of Science and Cumulative Index to Nursing and Allied Health Literature) were searched from inception to January 2020. Study quality was rated using the Newcastle-Ottawa Scale. Pooled estimates for each environmental factor were generated using a random-effects, inverse-variance method, where possible. The remaining environmental factors were synthesized in narrative form.

Results

This review includes 66 environmental factors from 39 studies (11 cohort and 28 case-control studies) over 45 years. Study sample sizes ranged from 41 to 1.9 million participants. Eight environmental factors from ten studies were meta-analysed. Caesarean section delivery was associated with increased JIA risk [pooled odds ratio (OR) 1.11, 95% CI: 1.01, 1.22]. Conversely, presence (vs absence) of siblings (pooled OR 0.60, 95% CI: 0.44, 0.81) and maternal prenatal smoking (pooled OR 0.70, 95% CI: 0.58, 0.84) were associated with decreased JIA risk.

Conclusion

This review identifies several environmental factors associated with JIA and demonstrates the huge breadth of environmental research undertaken over five decades. We also highlight the challenges of combining data collected over this period due to limited between study comparability, evolution in healthcare and social practices, and changing environment, which warrant consideration when planning future studies.

"Environmental risk factors associated with juvenile idiopathic arthritis associated uveitis: a systematic review of the literature"

BACKGROUND

Juvenile idiopathic arthritis associated uveitis (JIA-U) is the most common extra-articular manifestation of juvenile idiopathic arthritis (JIA) and carries considerable risk to vision. The aim of this systematic review was to synthesise evidence of environmental risk factors for JIA-U and identify risk factors which may be modifiable or used to stratify JIA patients.

METHODS

This systematic review was carried out in accordance with PRISMA guidelines. Four online databases - Cumulative Index of Nursing and Allied Health Literature, Web of Science, MEDLINE and Embase - were searched from database inception to 12th August 2020. Identified studies were screened by two independent reviewers against pre-defined inclusion and exclusion criteria. Data was extracted from all primary studies meeting inclusion criteria and independently checked.

RESULTS

We identified three studies from 895 unique records which met the inclusion criteria, each examining a different environmental risk factor. This systematic review includes 973, predominantly female, participants with JIA across these three studies. The use of allergy medication or documentation of "allergy"/"allergic" in the medical records was associated with an increased risk of JIA-U in all models presented. Vitamin D sufficiency was associated with reduced risk of JIA-U. There was insufficient evidence to support an association between seasonality and JIA-U.

CONCLUSIONS

This review identifies a potential role for allergy and vitamin D in JIA-U. It also illustrates the paucity of data regarding environmental risk factors for JIA-U and highlights the need for further research to both identify additional risk factors and replicate existing findings.

Cumulative Damage in Juvenile Idiopathic Arthritis: A Multicenter Study From the Pediatric Rheumatology Arab Group

OBJECTIVE

To report the cumulative articular and extraarticular damage in Arab children with juvenile idiopathic arthritis (JIA) and to identify variables that correlate with disease damage.

METHODS

We conducted a multicenter, cross-sectional study among 14 pediatric rheumatology centers from 7 Arab countries. JIA patients who met the International League of Associations for Rheumatology classification criteria and had a disease duration of >1 year were enrolled. Disease activity status was assessed using the Juvenile Arthritis Multidimensional Assessment Report. Disease damage was assessed by the Juvenile Arthritis Damage Index, articular (JADI-A) and extraarticular (JADI-E).

RESULTS

A total of 702 (471 female) JIA patients with a median age of 11.3 years (interquartile range [IQR] 8.0-14.0 years) were studied. Median age at disease onset was 5 years (IQR 2.0-9.0 years) and the median disease duration was 4 years (IQR 2.0-7.0 years). The most frequent JIA categories were oligoarticular JIA (34.9%), polyarticular JIA (29.5%), and systemic JIA (24.5%). Clinical remission was achieved in 73.9% of patients. At the last clinic visit, 193 patients experienced joint damage, with a mean ± SD JADI-A score of 1.7 ± 4.5, while 156 patients had extraarticular damage, with a mean ± SD JADI-E score of 0.5 ± 1.1. Patients with enthesitis-related arthritis had the highest JADI-A score. JADI-A correlated significantly with the presence of a family history of JIA. JADI-A and JADI-E had a significant correlation with long disease duration.

CONCLUSION

Cumulative damage was common in this Arab JIA cohort, and consanguinity and JIA in a sibling were frequent findings and were associated with a greater cumulative damage.

New or vanishing frontiers: LACC1-associated juvenile arthritis

BACKGROUND

The classification and pathogenic basis of juvenile idiopathic arthritis (JIA) are a subject of some controversy. Essentially, JIA is an exclusion diagnosis that represents a phenotypically heterogeneous group of arthritis of unknown origin. Familial aggregation of JIA supports the concept of genetic influence in the pathogenesis of JIA.

OBJECTIVE

To present the spectrum of laccase domain-containing 1 (LACC1)-associated juvenile arthritis with clinical, biochemical, and molecular genetic data of a cohort of 43 patients, including 11 previously unpublished cases.

METHODS

We studied 11 patients with different categories of juvenile idiopathic arthritis from 5 consanguineous families, all from Saudi Arabia, except 2 patients who were of Jordanian ethnicity. Whole-exome sequencing was used to identify the disease-causing variant of LACC1. We also reviewed the clinical spectrum and molecular genetic data of previously published cases of LACC1-associated juvenile arthritis.

RESULTS

This study describes 43 (29 females, 14 males) patients from consanguineous multiplex families. Most of the included patients were of Arab origin with 86% having early onset disease. The most frequent categories were systemic (19 patients) and rheumatoid factor-negative polyarticular (19 patients). Thirty-seven (86%) had progressive erosive arthritis and 10 (23.3%) had persistent limb lymphedema. None of the patients had features of macrophage activation syndrome. Genetic analysis confirmed LACC1 variant in all patients; 22 patients had common founder mutation (LACC1: c.850T > C,p.C284R), while the others showed different LACC1 variants. All patients were treated aggressively with methotrexate and sequential biologic agents. Most of them showed a poor response to treatment.

CONCLUSION

This report expands the pathogenic variants of LACC1 and the clinical spectrum associated with this genetic subset of juvenile arthritis. The predominance of autosomal-recessive inheritance and strong genetic evidence allowed us to propose LACC1-associated juvenile arthritis as a distinct disorder.

The clinical effectiveness and cost-effectiveness of abatacept, adalimumab, etanercept and tocilizumab for treating juvenile idiopathic arthritis: a systematic review and economic evaluation

BACKGROUND

Juvenile idiopathic arthritis (JIA) is characterised by joint pain, swelling and a limitation of movement caused by inflammation. Subsequent joint damage can lead to disability and growth restriction. Treatment commonly includes disease-modifying antirheumatic drugs (DMARDs), such as methotrexate. Clinical practice now favours newer drugs termed biologic DMARDs where indicated.

OBJECTIVE

To assess the clinical effectiveness and cost-effectiveness of four biologic DMARDs [etanercept (Enbrel(®), Pfizer), abatacept (Orencia(®), Bristol-Myers Squibb), adalimumab (Humira(®), AbbVie) and tocilizumab (RoActemra(®), Roche) - with or without methotrexate where indicated] for the treatment of JIA (systemic or oligoarticular JIA are excluded).

DATA SOURCES

Electronic bibliographic databases including MEDLINE, EMBASE, The Cochrane Library and the Database of Abstracts of Reviews of Effects were searched for published studies from inception to May 2015 for English-language articles. Bibliographies of related papers, systematic reviews and company submissions were screened and experts were contacted to identify additional evidence.

REVIEW METHODS

Systematic reviews of clinical effectiveness, health-related quality of life and cost-effectiveness were undertaken in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. A cost-utility decision-analytic model was developed to compare the estimated cost-effectiveness of biologic DMARDs versus methotrexate. The base-case time horizon was 30 years and the model took a NHS perspective, with costs and benefits discounted at 3.5%.

RESULTS

Four placebo-controlled randomised controlled trials (RCTs) met the inclusion criteria for the clinical effectiveness review (one RCT evaluating each biologic DMARD). Only one RCT included UK participants. Participants had to achieve an American College of Rheumatology Pediatric (ACR Pedi)-30 response to open-label lead-in treatment in order to be randomised. An exploratory adjusted indirect comparison suggests that the four biologic DMARDs are similar, with fewer disease flares and greater proportions of ACR Pedi-50 and -70 responses among participants randomised to continued biologic DMARDs. However, confidence intervals were wide, the number of trials was low and there was clinical heterogeneity between trials. Open-label extensions of the trials showed that, generally, ACR responses remained constant or even increased after the double-blind phase. The proportions of adverse events and serious adverse events were generally similar between the treatment and placebo groups. Four economic evaluations of biologic DMARDs for patients with JIA were identified but all had limitations. Two quality-of-life studies were included, one of which informed the cost-utility model. The incremental cost-effectiveness ratios (ICERs) for adalimumab, etanercept and tocilizumab versus methotrexate were £38,127, £32,526 and £38,656 per quality-adjusted life year (QALY), respectively. The ICER for abatacept versus methotrexate as a second-line biologic was £39,536 per QALY.

LIMITATIONS

The model does not incorporate the natural history of JIA in terms of long-term disease progression, as the current evidence is limited. There are no head-to-head trials of biologic DMARDs, and clinical evidence for specific JIA subtypes is limited.

CONCLUSIONS

Biologic DMARDs are superior to placebo (with methotrexate where permitted) in children with (predominantly) polyarticular course JIA who have had an insufficient response to previous treatment. Randomised comparisons of biologic DMARDs with long-term efficacy and safety follow-up are needed to establish comparative effectiveness. RCTs for JIA subtypes for which evidence is lacking are also required.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42015016459.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Noninflammatory disorders mimic juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is the most common chronic childhood arthritis; unfortunately, no diagnostic tool is available. Genetic disorders with musculoskeletal involvement that mimic chronic polyarthritis should be considered in the differential diagnostics of JIA. Normal inflammatory markers and characteristic radiological features are able to distinguish these disorders from JIA. Timely diagnosis of these disorders is crucial to offer the family proper genetic counseling and avoid inappropriate therapy. This review highlights selected noninflammatory disorders that often present with articular manifestations and that are often mislabeled as JIA. The focus is on the clinical, biochemical, and imaging features of these disorders.

Education and employment in patients with juvenile idiopathic arthritis - a standardized comparison to the German general population

BACKGROUND

Although several studies show that JIA-patients have significantly lower employment rates than the general population, the research on educational and occupational attainments in patients with juvenile idiopathic arthritis (JIA) remain conflicting most likely due to small sample sizes. Therefore, aim of this study is to compare the educational achievements and employment status of 3698 JIA-patients with the German general population (GGP).

METHODS

"SEPIA" was a large cross-sectional study on the current status of a historic cohort of JIA-patients treated in a single center between 1952 and 2010. For the analyses of education and employment a sub-cohort was extracted, including only adult cases with a confirmed diagnosis of JIA (N = 2696). Participants were asked to fill out a standardized written questionnaire on education and employment. Outcome measures (education/unemployment) were directly standardized to the GGP using data obtained from the National Educational Panel Study 2013 (N = 11,728) and the German Unemployment Statistics 2012 of the Federal Statistical Office (N = 42,791,000).

RESULTS

After age- and sex-standardization, 3% (95% Confidence Interval 1.9 to 4.1%) more of the JIA-patients (26%) than of the GGP (23%) had only reached primary education. In contrast, parents of JIA-patients had similar levels of education as parents in the GGP. With a standardized difference of 0.2% (95% CI: 0.16 to 0.19%), the unemployment rate in JIA-patients was slightly, but not significantly higher than in the GGP. Stratifying for disease duration and the current treatment status, differences were confirmed for persons diagnosed before 2001, whilst for patients diagnosed after 2000, differences were found only in JIA-patients with ongoing disease. Medium and high educational achievements did not differ statistically significant between JIA patients and the GPP.

CONCLUSION

Educational achievements in German JIA-patients are significantly lower than in the GGP. Furthermore we were able to identify a slightly higher level of unemployment, especially in those with still under treatment and longer disease duration. Better treatment options as well as further development of social support programs might help to overcome this lifelong secondary effect of JIA.

Inflammatory Markers and Disease Activity in Juvenile Idiopathic Arthritis

OBJECTIVE

To evaluate the post treatment changes in disease activity and inflammatory markers over time in longitudinal follow-up involving different subtypes of juvenile idiopathic arthritis (JIA) patients.

METHODS

This prospective longitudinal study, carried out over a period of 2 y, included JIA patients, both old and new, with high disease activity. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), ferritin, CHAQ (Childhood Health Assessment Questionnaire) score and JADAS27 (Juvenile Arthritis Disease Activity score with 27 active joint counts) were estimated at the initial visit, 6 mo, 12 mo and 18 mo of follow-up.

RESULTS

Out of 40 patients, 10 had persistent oligoarthritis, 11 had rheumatoid factor (RF) positive polyarthritis, 8 had RF negative polyarthritis and 11 had systemic JIA. Twenty-one of them were females. Serum ferritin was highly elevated in systemic JIA patients with a range of 750-7712 ng/ml at the initial visit. All three inflammatory markers with disease activity score decreased significantly over 18-mo-period in all four subtypes. At any visit, all these parameters had largest value in systemic arthritis and least in oligoarthritis variety. At 18 mo, all oligoarthritis and polyarthritis cases had low or inactive disease while none of the systemic JIA patients achieved inactive disease. Elevated ESR and serum ferritin was found in all at 18 mo. CRP normalized in some with low or moderate disease activity.

CONCLUSIONS

Inflammatory markers and disease activity decreased in all subtypes of JIA with treatment without biologics. Acute phase markers often remain elevated in inactive disease state. Similarly, normal level of an inflammatory marker does not necessarily indicate absence of active disease.

Long-Term Health-Related Quality of Life in German Patients with Juvenile Idiopathic Arthritis in Comparison to German General Population

Objective

Aims of the study were to investigate health-related quality of life (HRQOL) in adult patients with former diagnosis of Juvenile Idiopathic Arthritis (JIA), to compare their HRQOL with the general population and to identify factors related to a poor outcome.

Methods

In 2012, a cross-sectional survey was performed by mailing a questionnaire to a large cohort of former and current patients of the German Centre for Rheumatology in Children and Adolescents. Only adult patients (≥18 years) with a diagnosis compatible with JIA were included (n = 2592; response 66%). The questionnaire included information about HRQOL (EQ5D), disease-related questions and socio-demographics. Prevalence and 95% confidence intervals (CI) of problems with mobility, self-care, usual activities, pain and anxiety/depression were standardized to the German general population. Factors associated with low HRQOL in JIA patients were identified using logistic regression models.

Results

Sixty-two percent of the study population was female; age range was 18–73 years. In all dimensions, JIA patients reported statistically significantly more problems than the general population with largest differences in the pain dimension (JIA patients 56%; 95%CI 55–58%; general population 28%; 26–29%) and the anxiety/depression dimension (28%; 27–29% vs. 4%; 4–5%). Lower HRQOL in JIA patients was associated with female sex, older age, lower level of education, still being under rheumatic treatment and disability.

Conclusions

HRQOL in adult JIA patients is considerably lower than in the general population. As this cohort includes historic patients the new therapeutic schemes available today are expected to improve HRQOL in future.

Developing a Predictive Score for Chronic Arthritis among a Cohort of Children with Musculoskeletal Complaints--The Chronic Arthritis Score Study

OBJECTIVE

To explore if features obtained from a carefully taken medical history can be predictors of the final diagnosis in children with musculoskeletal complaints.

STUDY DESIGN

We collected detailed clinical information on 178 children referred to our Pediatric Immunology and Rheumatology Unit by their primary care pediatrician for musculoskeletal complaints; a univariate logistic analysis was performed to identify variables correlated with the diagnosis of chronic arthritis. The variables identified were combined in a linear score that indicates the probability for a patient with musculoskeletal pain to receive the diagnosis of chronic arthritis.

RESULTS

The joint swelling pattern (P < .0001), the precipitating factors of pain (P = .001), the duration of morning stiffness (P < .0001) and the frequency of pain (P < .0001), were found to be independently correlated with the diagnosis of chronic arthritis and were used to develop a diagnostic score. This score had a sensitivity of 90.9% and specificity of 95.3%.

CONCLUSIONS

We developed a score that could be useful in the daily clinical routine to correctly direct the differential diagnosis in a child with musculoskeletal complaints, rationalizing time and resources necessary to reach a definitive diagnosis.

Spirometric evaluation in juvenile idiopathic arthritis: data from eastern India

OBJECTIVE

To evaluate lung function in juvenile idiopathic arthritis (JIA) patients.

METHODS

This was a case control study carried out at Institute of Post-Graduate Medical Education & Research, Kolkata, involving JIA patients between 5 and 12 y. They were diagnosed and classified on the basis of International League of Associations for Rheumatology (ILAR) criteria and compared with same number of age, sex, height and weight matched controls. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC ratio, forced expiratory flow between 25 and 75% of vital capacity (FEF25-75%) and peak expiratory flow rate (PEFR) of cases were compared to those of matched controls.

RESULTS

Among 36 JIA patients initially recruited, 9 were excluded. Of the remaining 27 patients, male: female ratio was 17:10. Mean age, height and weight of JIA patients were 9.15 y, 124.67 cm and 23.78 kg respectively. Six patients had oligoarthritis, 3 had rheumatoid factor positive (RF+) polyarthritis, 10 had rheumatoid factor negative (RF-) polyarthritis and 8 had systemic JIA. Eleven patients had active disease and 15 patients required methotrexate. None had respiratory symptoms. Mean duration of the disease was 2.96 y. Mean FVC and FEV1 were significantly less in JIA patients compared to controls (p value=0.0003 and 0.0007, respectively). FEV1/FVC in both the groups was similar (p value=0.96). Mean Z scores for FVC and FEV1 were significantly higher in JIA patients (p value=0.0064 and 0.0030, respectively).

CONCLUSION

Spirometry in JIA patients demonstrated statistically significant restrictive pattern of alteration in pulmonary function.

Diagnosis and classification of juvenile idiopathic arthritis

In recent years, it has become increasingly clear that the term Juvenile Idiopathic Arthritis (JIA) comprises not one disease but several. Moreover, recent studies strongly suggest that some of these clinico-pathophysiologic entities appear to cross current diagnostic categories. The ultimate goal of the JIA classification is to facilitate development of better, more specific therapy for different forms of disease though improved understanding of pathophysiology. The past two decades have witnessed significant advances in treatment and improved outcomes for many children with chronic arthritis. However, understanding of the basic biologic processes underlying these diseases remains far from complete. As a result, even the best biologic agents of today represent "halfway technologies". Because they do not treat fundamental biologic processes, they are inherently expensive, need to be given for a long time in order to ameliorate the adverse effects of chronic inflammation, and do not cure the disease. Pediatric rheumatology is now entering an era in which diagnostic categories may need to change to keep up with discovery. A more precise, biologically based classification is likely to contribute to development of more specific and improved treatments for the various forms of childhood arthritis. In this review, we discuss how genetic, gene expression, and immunologic findings have begun to influence how these diseases are understood and classified.

Disease of the year: juvenile idiopathic arthritis-associated uveitis--classification and diagnostic approach

Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease and the most common systemic association of uveitis in children. JIA is subdivided into seven clinically more homogeneous subtypes, using the International League of Associations for Rheumatology (ILAR) classification system: systemic arthritis, oligoarthritis, rheumatoid factor (RF)-negative polyarthritis, RF-positive polyarthritis, psoriatic arthritis, enthesitis-related arthritis, and undifferentiated arthritis. Uveitis is very rare in patients with systemic onset JIA and in patients with juvenile-onset rheumatoid arthritis. Patients with early-onset antinuclear antibody (ANA)-positive oligoarticular JIA have the highest risk of developing chronic iridocyclitis. Ocular involvement in enthesitis-related arthritis is characterized by recurrent acute symptomatic iridocyclitis. The diagnosis and differential diagnosis of JIA are based on history, physical examination, and laboratory investigations, including complete blood count, acute-phase reactants, ANA, RF, HLA-B27, and musculoskeletal imaging studies. Recent studies have revealed distinct gene expression profiles that may be useful in the diagnosis, classification, and follow-up of JIA patients.

Juvenile idiopathic arthritis in the new world of biologics

Juvenile idiopathic arthritis results in significant pain and disability in both children and adults. Advances in treatment resulting in improved long-term outcomes have occurred; however, an emphasis on early and aggressive diagnosis and management hopes to improve outcomes further. Juvenile idiopathic arthritis remains a clinical diagnosis of exclusion, but further research may delineate biological markers associated with the disease and its subtypes. Therapy for patients includes intra-articular steroid injections, disease modifying agents such as methotrexate and biological agents. Biological agents have provided exciting new therapeutic options in the last decade; however, long-term side effects of modulating the immune system are not yet fully understood. Systemic steroids may also be required but their long-term use is avoided. Uveitis needs to be screened for in all of those with the diagnosis. Multidisciplinary team care is required in managing these young people.

Parent perceptions of child vulnerability are associated with functioning and health care use in children with chronic pain

CONTEXT

The extent to which parent variables are associated with the level of disability experienced by children with persistent pain has been an area of increasing research.

OBJECTIVES

To evaluate the extent to which parent perceptions of their child's vulnerability are associated with functioning and health care utilization among children with persistent pain. We also evaluated whether perceptions of child vulnerability contribute to an indirect relationship between parent distress and child functioning and/or child health care utilization.

METHODS

The study sample comprised 87 patients aged 6-18 years and a parent attending a chronic pain clinic. Children completed questionnaires on functional limitations, and parents completed questionnaires on parent distress, perceptions of child vulnerability, and extent of the child's pain-related health care utilization. Hierarchical regression and bootstrapping mediation analyses were used to test study hypotheses.

RESULTS

Perceptions of child vulnerability were found to be clinically elevated in nearly half (46%) of parents/caregivers, and average child functional ability for the sample was substantially lower than healthy norms. Parent perceptions of greater child vulnerability were significantly associated with poorer child functioning and more child pain-related health care utilization regardless of child age, sex, and duration of persistent pain. Parent distress was found to be indirectly related to child health care utilization through parent perceptions of child vulnerability but directly related to child functioning.

CONCLUSION

Parent perceptions of child vulnerability appear important for understanding levels of child functional limitations and health care utilization among children with chronic pain.

Emotion regulation predicts pain and functioning in children with juvenile idiopathic arthritis: an electronic diary study

OBJECTIVES

This study utilized e-diaries to evaluate whether components of emotion regulation predict daily pain and function in children with juvenile idiopathic arthritis (JIA).

METHODS

43 children ages 8-17 years and their caregivers provided baseline reports of child emotion regulation. Children then completed thrice daily e-diary assessments of emotion, pain, and activity involvement for 28 days. E-diary ratings of negative and positive emotions were used to calculate emotion variability and to infer adaptive emotion modulation following periods of high or low emotion intensity. Hierarchical linear models were used to evaluate how emotion regulation related to pain and function.

RESULTS

The attenuation of negative emotion following a period of high negative emotion predicted reduced pain; greater variability of negative emotion predicted higher pain and increased activity limitation. Indices of positive emotion regulation also significantly predicted pain.

CONCLUSIONS

Components of emotion regulation as captured by e-diaries predict important health outcomes in children with JIA.

Biologic similarities based on age at onset in oligoarticular and polyarticular subtypes of juvenile idiopathic arthritis

OBJECTIVE

To explore biologic correlates to age at onset in patients with juvenile idiopathic arthritis (JIA) using peripheral blood mononuclear cell (PBMC) gene expression analysis.

METHODS

PBMCs were isolated from 56 healthy controls and 104 patients with recent-onset JIA (39 with persistent oligoarticular JIA, 45 with rheumatoid factor-negative polyarticular JIA, and 20 with systemic JIA). RNA was amplified and labeled using NuGEN Ovation, and gene expression was assessed with Affymetrix HG-U133 Plus 2.0 GeneChips.

RESULTS

A total of 832 probe sets revealed gene expression differences (false discovery rate 5%) in PBMCs from children with oligoarticular JIA whose disease began before age 6 years (early-onset disease) compared with those whose disease began at or after age 6 years (late-onset disease). In patients with early-onset disease, there was greater expression of genes related to B cells and less expression of genes related to cells of the myeloid lineage. Support vector machine analyses identified samples from patients with early- or late-onset oligoarticular JIA (with 97% accuracy) or from patients with early- or late-onset polyarticular JIA (with 89% accuracy), but not from patients with systemic JIA or healthy controls. Principal components analysis showed that age at onset was the major classifier of samples from patients with oligoarticular JIA and patients with polyarticular JIA.

CONCLUSION

PBMC gene expression analysis reveals biologic differences between patients with early-and late-onset JIA, independent of classification based on the number of joints involved. These data suggest that age at onset may be an important parameter to consider in JIA classification. Furthermore, pathologic mechanisms may vary with age at onset, and understanding these processes may lead to improved treatment of JIA.

Classification of juvenile spondyloarthritis: Enthesitis-related arthritis and beyond

Spondyloarthritis (SpA) refers to a spectrum of immune-mediated inflammatory diseases with overlapping features, which differ from other types of inflammatory arthritis in genetic predisposition, pathogenesis and outcome. SpA frequently involves the axial skeleton, and can result in abnormal bone formation with eventual ankylosis of the spine, resulting in substantial disability. SpA often begins as an 'undifferentiated' disease, the presentation of which differs in children and adults; most notably, spinal involvement is uncommon, while hip arthritis and enthesitis are frequently seen in juvenile-onset disease. Currently, the classification of SpA in adults and children is approached differently. Using the International League of Associations for Rheumatology (ILAR) system for juvenile idiopathic arthritis, most childhood SpA is classified as enthesitis-related arthritis. However, in contrast to adult SpA classification, the presence of, or a family history of, psoriasis dictates a separate category of juvenile idiopathic arthritis. More importantly, the ILAR system does not specifically recognize the presence of axial disease in juvenile SpA. Resolution of these issues will improve communication and the transitioning of patients from pediatric to adult clinics, will facilitate research in genetics and pathogenesis, and will be particularly important in the evaluation of tumor necrosis factor inhibitors and other biologic agents for early, axial SpA.

Parent pain responses as predictors of daily activities and mood in children with juvenile idiopathic arthritis: the utility of electronic diaries

The present study used electronic diaries to examine how parent responses to their child's pain predict daily adjustment of children with juvenile idiopathic arthritis (JIA). Nine school-aged children with JIA along with one of their parents completed thrice-daily assessments of pain-related variables, activity participation, and mood using handheld computers (Palm pilots) for 14 days, yielding a potential of 42 child and parent assessments for each dyad. Children provided information on current pain level, mood, and participation in social, physical, and school activities. Parents independently rated their own mood as well as their behavioral responses to their child's pain at the same time points using a separate handheld computer. Results of multilevel modeling analyses demonstrated that use of "protective" pain responses by parents significantly predicted decreases in child activity and positive mood, with an even stronger inverse relationship between protective pain response and positive mood observed in children with higher than average disease severity. Protective pain responses were not found to be significantly predictive of daily negative mood in children. The use of "distracting" responses by parents significantly predicted less child activity restrictions but only in children having higher disease severity. There also was an unexpected trend in which parent use of more distracting pain responses tended to be associated with lower child positive mood. These preliminary findings suggest the importance of the parent in influencing adjustment in children with JIA and lend support to the incorporation of parents into comprehensive pain management approaches. The potential benefits of using electronic daily diaries as a strategy to examine pain and adjustment in children with JIA pain are discussed.

Reuse of terminological resources for efficient ontological engineering in Life Sciences

This paper is intended to explore how to use terminological resources for ontology engineering. Nowadays there are several biomedical ontologies describing overlapping domains, but there is not a clear correspondence between the concepts that are supposed to be equivalent or just similar. These resources are quite precious but their integration and further development are expensive. Terminologies may support the ontological development in several stages of the lifecycle of the ontology; e.g. ontology integration. In this paper we investigate the use of terminological resources during the ontology lifecycle. We claim that the proper creation and use of a shared thesaurus is a cornerstone for the successful application of the Semantic Web technology within life sciences. Moreover, we have applied our approach to a real scenario, the Health-e-Child (HeC) project, and we have evaluated the impact of filtering and re-organizing several resources. As a result, we have created a reference thesaurus for this project, named HeCTh.

Pharmacotherapy of Juvenile Idiopathic Arthritis

Juvenile idiopathic arthritis is the most common rheumatic disorder of childhood, and is defined as arthritis beginning prior to the age of 16 years, lasting more than 6 weeks, with an unknown cause. Seven subtypes of juvenile idiopathic arthritis have recently been categorized and named. These subtypes differ broadly in the number of affected joints and the presence of systemic illness. Although many children with juvenile idiopathic arthritis may achieve remission prior to entering adulthood, many others will continue to have debilitating disease into adulthood. Pharmacotherapy plays a major role in the treatment of juvenile idiopathic arthritis. Nonsteroidal anti-inflammatory drugs and corticosteroids can be beneficial for many children and are used as initial therapy. Methotrexate may offer benefits to children unresponsive to these initial agents. Studies evaluating the use of several biologic agents and immunosuppressants have recently been published, and the role of these drugs for children with juvenile idiopathic arthritis is being assessed. Major clinical trials and pediatric implications are reviewed.

Juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA), a term referring to a group of disorders characterized by chronic arthritis, is the most common chronic rheumatic illness in children and is a significant cause of short- and long-term disability. This article discusses the classification, differential diagnosis, and treatment of JIA.

Pediatric rheumatology for the adult rheumatologist II: uveitis in juvenile idiopathic arthritis

Uveitis is an important and frequent extra-articular manifestation of juvenile idiopathic arthritis (JIA) that may result in poor visual outcome. Without early detection and aggressive therapy, the uveitis and topical steroid therapy used to treat it may result in cataracts, glaucoma, and even blindness. Fortunately, a variety of systemically administered anti-inflammatory agents have been found useful for the treatment of JIA associated uveitis. Methotrexate is often the first line disease modifying systemic agent used to help wean topical corticosteroids, but when this is not sufficiently effective there are a variety of other systemic medicines available. In particular, one of the tumor necrosis factor-alpha inhibitors, infliximab, has shown some promising results in difficult to treat JIA associated uveitis. With early screening and detection combined with aggressive therapy in difficult to treat cases, the morbidity associated with uveitis as part of JIA is on the decline.

Long-term outcome of juvenile idiopathic arthritis following a placebo-controlled trial: sustained benefits of early sulfasalazine treatment

OBJECTIVES

A previous 24-week randomised trial demonstrated that sulfasalazine (SSZ) treatment was superior to placebo (PLAC) in suppressing disease activity in patients with oligo- and polyarticular onset juvenile idiopathic arthritis (JIA). The current study determines the long-term outcome of the trial participants and evaluates whether the benefits of SSZ allocation are sustained over time.

METHODS

Between 2001 and 2003, 32 SSZ and 29 PLAC patients (90% of all patients) were prospectively examined clinically and by chart review, median 9 years (range 7 to 10) after trial inclusion. In the follow-up assessment, variables of the American College of Rheumatology Pediatric 30 (ACR Pedi 30) criteria were collected. The assessor was blinded to trial treatment allocation.

RESULTS

After the trial, patients had been routinely followed in rheumatology referral centres, and treated at the discretion of the attending physician. Almost all patients continued or started disease-modifying antirheumatic drugs (DMARDs) (SSZ 91%, PLAC 93%; SSZ treatment in about 80%). DMARD treatment appeared less intensive in the SSZ group as evidenced by a significantly shorter duration of SSZ use (median 2.5 vs 5.2 years; p = 0.02) and a trend towards less use of methotrexate and other DMARDs. More than one-third of the patients reported long periods of non-compliance with DMARD treatment in both groups. At follow-up, 74% of the patients had active joints, and 30% showed active polyarthritis. Almost all outcome scores were better for SSZ compared with PLAC patients. Differences (often exceeding 50%) were significant for the number of active joints, patients' overall well-being, number of patients with episodes of clinical remission off medication (CROM) and duration of these episodes, patients in CROM and ACR Pedi 30 response at follow-up. Additional exploratory analyses performed to detect potential confounders related to patient characteristics or follow-up treatment showed that DMARD treatment compliance was positively correlated with an ACR Pedi 30 response (odds ratio 3.8, 95% confidence interval (CI) 1.1 to 13.4; p = 0.03). Adjusted for compliance, an SSZ patient was 4.2 times as likely as a PLAC patient to be an ACR Pedi 30 responder at follow-up (95% CI 1.3 to 14.3; p = 0.02).

CONCLUSIONS

This follow-up study shows that effective suppression of disease activity by SSZ treatment early in active disease in JIA patients has beneficial effects that persist for many years. Given these results, compliance with DMARD treatment deserves serious attention.

Genomic progress in pediatric arthritis: recent work and future goals

PURPOSE OF REVIEW

Pediatric arthritis is a heterogeneous group of chronic arthropathies that are influenced by complex genetic and perhaps environmental factors. Interacting genetic traits may one day be identified that provide the basis for predicting disease risk and other characteristics such as course, age of onset, and disease severity. The purpose of this review is to describe the recent progress towards identifying the multiple genes related to pediatric arthritis and understand how they relate to each other and to disease pathology.

RECENT FINDINGS

Candidate gene studies are by far the most widely reported type of genetic studies to date for juvenile arthritis with only one genome-wide screen for juvenile rheumatoid/idiopathic arthritis published. Particular attention is paid to studies of candidate genes with potential immunological roles and those associated with other forms of autoimmunity.

SUMMARY

Genomic studies may perhaps one day provide information to allow future classification systems of childhood arthritis to include molecular biomarkers as a complement to clinical observations, as well as understand how these genes or proteins relate to each other and to disease pathogenesis.

Classification of the spondyloarthropathies

PURPOSE OF REVIEW

The spondyloarthropathies are a group of conditions which share similar clinical features. Classification criteria permit separation of the conditions, allow better targeting of therapies, better measurement of outcomes, and better prognostic information. Early diagnosis remains problematic, but validated criteria for established disease are now emerging.

RECENT FINDINGS

Histopathology and histochemistry are providing a better understanding of the underlying process of inflammatory arthritis in spondyloarthropathy and other inflammatory arthritides. Early disease, however, continues to challenge current criteria. Sophisticated imaging with magnetic resonance imaging is being increasingly used and is proving useful for early diagnosis as well as helping to understand the pathophysiology of disease. Juvenile idiopathic arthritis continues to provide problems and criteria have recently been modified to allow a greater clinical utility and inclusion of more patients. Poststreptococcal reactive arthritis appears to be a heterogeneous clinical entity, with a group looking more like rheumatic fever and a group with spondyloarthropathy traits. It may be that the association is not streptococcal, but is a throat infection. Currently available criteria for psoriatic arthritis have been evaluated in a large cohort. Four of the criteria performed well with high specificity and sensitivity whereas the other two had moderate specificity and low sensitivity. It was shown that rheumatoid factor positivity does not exclude a diagnosis of psoriatic arthritis--the single most important clinical feature of this condition being the presence of psoriasis.

SUMMARY

The spondyloarthropathy classification criteria continue to be an area of development. This is most apparent in juvenile arthritis and psoriatic arthritis. The latter is currently undergoing intense scrutiny to develop classification criteria and outcome measures.

Juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA), a term referring to a group of disorders characterized by chronic arthritis, is the most common chronic rheumatic illness in children and is a significant cause of short- and long-term disability. This article discusses the classification, differential diagnosis, and treatment of JIA.