Normal scores for nine maneuvers of the Childhood Myositis Assessment Scale

Interferon type I signature associated with skin disease in juvenile dermatomyositis

Background

Interferon type I (IFN-I) signaling system hyperactivation plays an important role in the pathogenesis of juvenile dermatomyositis (JDM).

Aim of the study

To analyze IFN-I score with disease activity in patients with JDM.

Materials and methods

Clinical manifestations laboratory data, and treatment options were analyzed in 15 children with JDM. Disease activity was assessed by CMAS (childhood myositis assessment tool) and CAT (cutaneous assessment tool) scores. IFN I-score was assessed by RT-PCR quantitation of 5 IFN I-regulated transcripts (IFI44L, IFI44, IFIT3, LY6E, MXA1).

Results

All patients had skin and muscle involvement, some had a fever (n = 8), swallowing disorders (n = 4), arthritis (n = 5), calcinosis (n = 3), lipodystrophy (n = 2), and interstitial lung disease (n = 5). Twelve patients had elevated IFN I-score and it was correlated with skin disease activity. Ten patients had clinically active disease and the level of IFN I-score and its components were higher than in patients with inactive disease (8.8 vs. 4.2, p = 0.011). IFN I-score was evaluated in nine patients during follow-up. The simultaneous reduction of IFN I-score and its components, CMAS and CAT scores was observed.

Conclusion

Skin involvement in refractory JDM is a challenging problem requiring the use of additional medications. Serum IFN I-score might be suggested as the promising biomarker of skin disease activity in JDM patients. Further investigations on patients with JDM and recurrent disease activity are needed, especially concerning biomarkers that determine the response to JAK inhibitors and treatment options for patients who don't respond to them.

Juvenile idiopathic inflammatory myositis: an update on pathophysiology and clinical care

The childhood-onset or juvenile idiopathic inflammatory myopathies (JIIMs) are a heterogenous group of rare and serious autoimmune diseases of children and young people that predominantly affect the muscles and skin but can also involve other organs, including the lungs, gut, joints, heart and central nervous system. Different myositis-specific autoantibodies have been identified that are associated with different muscle biopsy features, as well as with different clinical characteristics, prognoses and treatment responses. Thus, myositis-specific autoantibodies can be used to subset JIIMs into sub-phenotypes; some of these sub-phenotypes parallel disease seen in adults, whereas others are distinct from adult-onset idiopathic inflammatory myopathies. Although treatments and management have much improved over the past decade, evidence is still lacking for many of the current treatments and few validated prognostic biomarkers are available with which to predict response to treatment, comorbidities (such as calcinosis) or outcome. Emerging data on the pathogenesis of the JIIMs are leading to proposals for new trials and tools for monitoring disease.

Long-term follow-up of Janus-kinase inhibitor and novel active disease biomarker in juvenile dermatomyositis

OBJECTIVE

To evaluate the use of Janus kinase inhibitor (JAKi) in treating JDM and develop cytokine biomarkers of active disease.

METHODS

This study involved a retrospective cohort study that evaluated JAKi in 101 JDM patients as well as a cross-sectional study of cytokines in 128 JDM patients and 30 controls between November 2017 and December 2021 in the Affiliated Children's Hospital of Capital Institute of Pediatrics (China).

RESULTS

During the median follow-up period of 19 months, 65.5% of the patients had improved rashes, and CAT-BM scores decreased. Overall, 39.6% of JDM patients eliminated glucocorticoids. Muscle strength was improved in all patients who had abnormal muscle strength before JAKi use. Patients and parents provided positive subjective reviews of JAKi, and no serious adverse events were reported. Potential side effects of JAKi included abnormal leukopoenia (14/95) and cough (16/83), which affected over 10% of the JDM patients. In the cytokine analysis, 12/34 cytokines were significantly elevated in active JDM patients. Compared with active JDM patients with multiple phenotypes, active JDM patients with only rashes demonstrated lower cytokine levels. Anti-NXP2-positive active patients had lower cytokine levels compared with those without positive anti-NXP2 antibodies. Among all increased cytokines, IL-1RA changed most dramatically, reaching over 793 times the mean of normal values. We developed a panel composed of six cytokines to differentiate active or stable status in our cohort (area under the curve = 0.8486, P < 0.05).

CONCLUSION

The preliminary evidence suggested that JAKi is a relatively safe and effective alternative for JDM patients. Cytokine profiles could well reflect the inflammatory status of JDM patients.

Transcriptomes of peripheral blood mononuclear cells from juvenile dermatomyositis patients show elevated inflammation even when clinically inactive

In juvenile dermatomyositis (JDM), the most common pediatric inflammatory myopathy, weakness is accompanied by a characteristic rash that often becomes chronic and is associated with vascular damage. We hoped to understand the molecular underpinnings of JDM, particularly when untreated, which would facilitate the identification of novel mechanisms and clinical targets that might disrupt disease progression. We studied the RNA-Seq data from untreated JDM peripheral blood mononuclear cells (PBMCs; n = 11), PBMCs from a subset of the same patients when clinically inactive (n = 8/11), and separate samples of untreated JDM skin and muscle (n = 4 each). All JDM samples were compared to non-inflammatory control tissues. The untreated JDM PBMCs showed a strong signature for type1 interferon response, along with IL-1, IL-10, and NF-κB. Surprisingly, PBMCs from clinically inactive JDM individuals had persistent immune activation that was enriched for IL-1 signaling. JDM skin and muscle both showed evidence for type 1 interferon activation and genes related to antigen presentation and decreased expression of cellular respiration genes. Additionally, we found that PBMC gene expression correlates with disease activity scores (DAS; skin, muscle, and total domains) and with nailfold capillary end row loop number (an indicator of microvascular damage). This included otoferlin, which was significantly increased in untreated JDM PBMCs and correlated with all 3 DAS domains. Overall, these data demonstrate that PBMC transcriptomes are informative of molecular disruptions in JDM and provide transcriptional evidence of chronic inflammation despite clinical quiescence.

Outcome Scores in Pediatric Rheumatology

PURPOSE OF REVIEW

Providing a summary of the latest research on outcome measures in juvenile idiopathic arthritis, childhood -onset systemic lupus erythematosus, and juvenile dermatomyositis.

RECENT FINDINGS

A rational management of patients with pediatric rheumatic diseases requires the regular assessment of the level of disease activity and damage, as well as the evaluation of therapeutic response through validated and standardized outcome measures. Ideally, such tools should be simple, feasible, and easily applicable in routine care. Recently, there has been a great deal of effort to refine existing tools and devise novel outcome measures, aiming to address the various aspects of disease impact and to improve the reliability of research studies and clinical trials. The newest outcome tools in pediatric rheumatology have markedly enlarged the spectrum of health domains assessable in a standardized way, thus increasing the reliability of evaluation of clinical response and fostering future clinical trials.

Juvenile Dermatomyositis: New Clues to Diagnosis and Therapy

PURPOSE OF REVIEW

To identify clues to disease activity and discuss therapy options.

RECENT FINDINGS

The diagnostic evaluation includes documenting symmetrical proximal muscle damage by exam and MRI, as well as elevated muscle enzymes-aldolase, creatine phosphokinase, LDH, and SGOT-which often normalize with a longer duration of untreated disease. Ultrasound identifies persistent, occult muscle inflammation. The myositis-specific antibodies (MSA) and myositis-associated antibodies (MAA) are associated with specific disease course variations. Anti-NXP-2 is found in younger children and is associated with calcinosis; anti-TIF-1γ+ juvenile dermatomyositis has a longer disease course. The diagnostic rash-involving the eyelids, hands, knees, face, and upper chest-is the most persistent symptom and is associated with microvascular compromise, reflected by loss of nailfold (periungual) end row capillaries. This loss is associated with decreased bioavailability of oral prednisone; the bioavailability of other orally administered medications should also be considered. At diagnosis, at least 3 days of intravenous methyl prednisolone may help control the HLA-restricted and type 1/2 interferon-driven inflammatory process. The requirement for avoidance of ultraviolet light exposure mandates vitamin D supplementation.

SUMMARY

This often chronic illness targets the cardiovascular system; mortality has decreased from 30 to 1-2% with corticosteroids. New serological biomarkers indicate occult inflammation: ↑CXCL-10 predicts a longer disease course. Some biologic therapies appear promising.

Serum protein biomarkers for juvenile dermatomyositis: a pilot study

BACKGROUND

Blood accessible biomarkers to assess disease activity and their response to therapies in Juvenile Dermatomyositis (JDM) are urgently needed. This pilot study aims to identify serum protein biomarkers associated with clinical disease activity in untreated JDM and their response to medical therapy.

METHODS

SomaScan® technology screened JDM patients for 1305 proteins at three points: 1) before start of treatment, 2) while on therapy, and 3) after treatment tapering when patients were clinically inactive. To define disease associated biomarkers, SomaScan® data from untreated JDM patients (n = 8) were compared to SomaScan® data from an independent age-matched healthy control group (n = 12). Longitudinal analysis defined treatment responsive proteins at three time points: untreated (7 samples), treated (7 samples), and clinically inactive (6 samples). To confirm the SomaScan® data, a subset of nine candidate proteins (CXCL11, IL-17B, IL-17D, IL-22, CXCL10, MCP-1, ANGPT2, MIF, IL-23) were tested by ELISA after adding 2 JDM (one untreated, one clinically inactive) serum samples to the same group of JDM girls (8 untreated, 7 treated; 7 clinically inactive) as well as with 17 age, gender, matched healthy controls.

RESULTS

Comparison of untreated JDM versus healthy controls identified 202 elevated and 49 decreased serum proteins in JDM patients with an adjusted p-value < 0.001. Only 82 out of 251 identified biomarker candidates responded to treatment while 12 out of these 82 proteins returned to their original untreated disease levels upon therapy tapering. The ELISA testing of the untreated samples for nine candidate proteins confirmed previously known biomarkers (CXCL10 or IP-10, CXCL11 or I-TAC and MCP-1) and identified novel biomarkers including IL-22, Angiopoetin-2, and IL-17B in a cross-sectional analysis comparing 8 untreated JDM and 17 age/gender matched controls. The subsequent longitudinal data by ELISA were not concordant for some biomarkers (IL-22 and IL-17B), but the other biomarkers either normalized or rebounded concordantly.

CONCLUSIONS

Blood accessible protein biomarkers reflecting JDM pathophysiology were identified; some of them rebounded after therapy was tapered. Further studies bridging these biomarkers to specific clinical features of JDM are required to confirm the clinical utility of these serum protein biomarkers.

Long-term outcome in children with juvenile dermatomyositis: A single-center study from north India

INTRODUCTION

Juvenile dermatomyositis (JDM) is the commonest childhood inflammatory myopathy. Outcome of children with JDM has improved significantly with current treatment protocols. We undertook this study to evaluate long-term outcome of these children using validated outcome measures.

METHODS

All children diagnosed as JDM and on follow-up for more than 2 years were eligible for enrolment. Cross-sectional examination was performed to assess signs of disease activity, damage, physical function and complications by using multiple validated outcome measures/tools.

RESULTS

Thirty-seven patients were enrolled, 19 were male. Median duration of disease at time of enrolment was 73 months (range 24-219 months) and median duration of follow-up was 60 months (range 24-218 months). Disease course was monocyclic in two-thirds of patients. Eight children were still on therapy at the time of enrolment. On Manual Muscle Testing 8, 3 and 7 children had severe weakness and mild to moderate weakness, respectively. Neck flexors were the most commonly affected muscle group. On abbreviated Cutaneous Assessment Tool, 14 children had evidence of cutaneous activity. More than 50% had at least 1 sign of cutaneous damage, most common signs being calcinosis and lipodystrophy. Nearly two-thirds of patients had damage in at least 1 organ using Myositis Damage Index. Nine children had physical dysfunction when assessed by Child Health Assessment Questionnaire.

CONCLUSIONS

Skin disease continued to be active in a significant proportion of patients. Features of damage, namely calcinosis and lipodystrophy, were seen in more than half. Muscle disease normalized in a large proportion of patients.

The natural history of children with joint hypermobility syndrome and Ehlers-Danlos hypermobility type: a longitudinal cohort study

Objectives

The objective of the manuscript was to describe the natural history of complaints and disability in children diagnosed with joint hypermobility syndrome (JHS)/Ehlers-Danlos-hypermobility type (EDS-HT) and to identify the constructs that underlie functional decline.

Methods

One hundred and one JHS/EDS-HT children were observed over 3 years and assessed at three time points on the following: functional impairments, quality of life, connective tissue laxity, muscle function, postural control and musculoskeletal and multi-systemic complaints. Cluster analysis was performed to identify subgroups in severity. Clinical profiles were determined for these subgroups, and differences were assessed by multivariate analysis of covariance. Mixed linear regression models were used to determine the subsequent trajectories. Finally, an exploratory factor analysis was used to uncover the underlying constructs of functional impairment.

Results

Three clusters of children were identified in terms of functional impairment: mild, moderately and severely affected. Functional impairment at baseline was predictive of worsening trajectories in terms of reduced walking distance and decreased quality of life (P ⩽ 0.05) over 3 years. Multiple interactions between the secondary outcomes were observed, with four underlying constructs identified. All four constructs (multi-systemic effects, pain, fatigue and loss of postural control) contributed significantly to disability (P ⩽ 0.046).

Conclusion

Children diagnosed with JHS/EDS-HT who have a high incidence of multi-systemic complaints (particularly, orthostatic intolerance, urinary incontinence and diarrhoea) and poor postural control in addition to high levels of pain and fatigue at baseline are most likely to have a deteriorating trajectory of functional impairment and, accordingly, warrant clinical prioritization.

Consensus-based recommendations for the management of juvenile dermatomyositis

Background

In 2012, a European initiative called Single Hub and Access point for pediatric Rheumatology in Europe (SHARE) was launched to optimise and disseminate diagnostic and management regimens in Europe for children and young adults with rheumatic diseases. Juvenile dermatomyositis (JDM) is a rare disease within the group of paediatric rheumatic diseases (PRDs) and can lead to significant morbidity. Evidence-based guidelines are sparse and management is mostly based on physicians' experience. Consequently, treatment regimens differ throughout Europe.

Objectives

To provide recommendations for diagnosis and treatment of JDM.

Methods

Recommendations were developed by an evidence-informed consensus process using the European League Against Rheumatism standard operating procedures. A committee was constituted, consisting of 19 experienced paediatric rheumatologists and 2 experts in paediatric exercise physiology and physical therapy, mainly from Europe. Recommendations derived from a validated systematic literature review were evaluated by an online survey and subsequently discussed at two consensus meetings using nominal group technique. Recommendations were accepted if >80% agreement was reached.

Results

In total, 7 overarching principles, 33 recommendations on diagnosis and 19 recommendations on therapy were accepted with >80% agreement among experts. Topics covered include assessment of skin, muscle and major organ involvement and suggested treatment pathways.

Conclusions

The SHARE initiative aims to identify best practices for treatment of patients suffering from PRD. Within this remit, recommendations for the diagnosis and treatment of JDM have been formulated by an evidence-informed consensus process to produce a standard of care for patients with JDM throughout Europe.

Reliability of the adult myopathy assessment tool in individuals with myositis

OBJECTIVE

The Adult Myopathy Assessment Tool (AMAT) is a 13-item performance-based battery developed to assess functional status and muscle endurance. The purpose of this study was to determine the intrarater and interrater reliability of the AMAT in adults with myositis.

METHODS

Nineteen raters (13 physical therapists and 6 physicians) scored videotaped recordings of patients with myositis performing the AMAT for a total of 114 tests and 1,482 item observations per session. Raters rescored the AMAT test and item observations during a followup session (mean ± SD 19 ± 6 days between scoring sessions). All raters completed a single, self-directed, electronic training module prior to the initial scoring session.

RESULTS

Intrarater and interrater reliability correlation coefficients were ≥0.94 for the AMAT functional subscale, endurance subscale, and total score (all P < 0.02 for Ho , ρ ≤0.75). All AMAT items had satisfactory intrarater agreement (kappa statistics with Fleiss-Cohen weights, with values κw = 0.57-1.00). Interrater agreement was acceptable for each AMAT item (κ = 0.56-0.89) except the sit up (κ = 0.16). The standard error of measurement and 95% confidence interval range for the AMAT total scores did not exceed 2 points across all observations (AMAT total score range 0-45).

CONCLUSION

The AMAT is a reliable, domain-specific assessment of functional status and muscle endurance for adult subjects with myositis. Results of this study suggest that physicians and physical therapists may reliably score the AMAT following a single training session. The AMAT functional subscale, endurance subscale, and total score exhibit interrater and intrarater reliability suitable for clinical and research use.

Joint hypermobility syndrome subclassification in paediatrics: a factor analytic approach

OBJECTIVE

To determine if exploratory factor analysis can identify subtypes comprising recognisable clinical patterns of the presenting signs and symptoms of children with joint hypermobility syndrome (JHS).

PATIENTS

Eighty-nine children with JHS aged 6-16 years.

METHODS

Twelve tests comprising anthropometric, musculoskeletal and functional assessments were conducted. Signs, symptoms and family history were recorded. Exploratory factor analysis was performed, factor scores generated, and correlations calculated to identify associations.

RESULTS

Sixty-six percent of the variance in the score set could be accounted for by five JHS subtypes (Eigenvalues >1). Factor 1, 'joint affected' JHS, had loadings on multiple joint pain, recurrent joint instability and postural orthostatic hypotension symptoms, and factor scores were associated with worse pain (r=0.48, p<0.01), fatigue (r=-0.54, p<0.01) and reduced health-related quality of life (HRQOL) (r=-0.5, p<0.01). Factor 2, 'athletic' JHS, loaded on muscle endurance, balance and motor skill proficiency, and scores were associated with less fatigue (r=0.3, p<0.01) and better HRQOL (r=0.44, p<0.01). Factor 3, 'systemic' JHS, loaded on skin involvement, incontinence symptoms, bowel involvement and recurrent joint instability, and was associated with reduced HRQOL (r=-0.24, p=0.03). Factor 4, 'soft tissue affected' JHS, loaded on recurrent soft tissue injuries and reduced muscle length, and was associated with greater fatigue (r=-0.43, p<0.01) and reduced HRQOL (r=-0.44, p<0.0001). Factor 5, 'high BMI' JHS, had high loadings on body mass index (BMI) for age, muscle endurance and no gastrointestinal involvement, and was associated with higher pain (r=0.33, p<0.01).

CONCLUSIONS

The presenting signs and symptoms of children with JHS can be summarised in five clinically recognisable subtypes.

Therapeutic approaches in the treatment of juvenile dermatomyositis in patients with recent-onset disease and in those experiencing disease flare: an international multicenter PRINTO study

OBJECTIVE

To evaluate response to therapy over a 24-month period in a large prospective international cohort of patients with juvenile dermatomyositis (DM).

METHODS

The study included 145 patients with recent-onset juvenile DM and 130 juvenile DM patients experiencing disease flare, all of whom were <18 years old. Disease activity parameters and therapeutic approaches in 4 geographic areas were analyzed at baseline and at 6, 12, and 24 months. Response was assessed according to the Pediatric Rheumatology International Trials Organization (PRINTO) juvenile DM response criteria, and data were reported "as observed" and in the intent-to-treat (ITT) population.

RESULTS

Patients with recent-onset juvenile DM at baseline had higher baseline disease activity and greater improvement over 24 months when compared to juvenile DM patients experiencing disease flare at baseline. Methotrexate (MTX) or high-dose corticosteroids were administered more frequently to patients with recent-onset juvenile DM, compared to juvenile DM patients experiencing disease flare, who were more likely to receive cyclosporine. Compared to patients from Western and Eastern Europe, a higher proportion of patients from South and Central America and North America received pulse steroids, and the average steroid dosage was higher in the North American and South and Central American patients. The use of MTX was similar in all 4 regions, while cyclosporin A was more frequently used in Western Europe. In the "as observed" analysis, 57.9% of the patients with recent-onset juvenile DM and 36.4% of the patients experiencing disease flare (P<0.001) reached at least a 70% response by PRINTO criteria at 6 months; these proportions had increased at month 24 to 78.4% and 51.2%, respectively (P<0.001). Corresponding results of the ITT analysis were much lower, with only one-third of the patients able to maintain the initial assigned therapy over 24 months.

CONCLUSION

Patients with recent-onset juvenile DM are more likely to achieve significant clinical improvement over 24 months, when compared to patients experiencing flares of juvenile DM. Internationally, various therapeutic approaches are used to treat this disease.

Comparison of children with onset of juvenile dermatomyositis symptoms before or after their fifth birthday in a UK and Ireland juvenile dermatomyositis cohort study

Objective

To compare 2 groups of children with juvenile dermatomyositis (DM), those with onset of symptoms before their fifth birthday versus those whose disease begins either on or after their fifth birthday, and to assess whether age at onset is associated with differences in disease presentation, treatments received, or outcomes 2 years after diagnosis.

Methods

Data were analyzed on children recruited to a UK juvenile DM cohort study with a diagnosis of probable or definite juvenile DM and less than 12 months between diagnosis and recruitment.

Results

Fifty-five (35%) of 157 children had onset of symptoms before their fifth birthday. At diagnosis, cutaneous ulceration was found in 32.7% of the younger group versus 11.8% of the older group (P = 0.003). Facial or body swelling was reported more often in the younger group, whereas headaches, alopecia, and Raynaud's phenomenon were all more frequently reported in the older group. At followup 2 years later, there were no important differences in outcomes between the groups. More than 90% of patients in both groups received both methotrexate and steroids. Twenty-three percent of both groups remained on steroids 2 years after diagnosis.

Conclusion

Our study showed that children with juvenile DM with disease onset at age <5 years are more likely to present with ulcerative skin disease and edema. There were no clinically significant differences in outcomes between the 2 groups.

The PRINTO criteria for clinically inactive disease in juvenile dermatomyositis

OBJECTIVES

To develop data-driven criteria for clinically inactive disease on and off therapy for juvenile dermatomyositis (JDM).

METHODS

The Paediatric Rheumatology International Trials Organisation (PRINTO) database contains 275 patients with active JDM evaluated prospectively up to 24 months. Thirty-eight patients off therapy at 24 months were defined as clinically inactive and included in the reference group. These were compared with a random sample of 76 patients who had active disease at study baseline. Individual measures of muscle strength/endurance, muscle enzymes, physician's and parent's global disease activity/damage evaluations, inactive disease criteria derived from the literature and other ad hoc criteria were evaluated for sensitivity, specificity and Cohen's κ agreement.

RESULTS

The individual measures that best characterised inactive disease (sensitivity and specificity >0.8 and Cohen's κ >0.8) were manual muscle testing (MMT) ≥78, physician global assessment of muscle activity=0, physician global assessment of overall disease activity (PhyGloVAS) ≤0.2, Childhood Myositis Assessment Scale (CMAS) ≥48, Disease Activity Score ≤3 and Myositis Disease Activity Assessment Visual Analogue Scale ≤0.2. The best combination of variables to classify a patient as being in a state of inactive disease on or off therapy is at least three of four of the following criteria: creatine kinase ≤150, CMAS ≥48, MMT ≥78 and PhyGloVAS ≤0.2. After 24 months, 30/31 patients (96.8%) were inactive off therapy and 69/145 (47.6%) were inactive on therapy.

CONCLUSION

PRINTO established data-driven criteria with clearly evidence-based cut-off values to identify JDM patients with clinically inactive disease. These criteria can be used in clinical trials, in research and in clinical practice.

Idiopathic inflammatory myopathies in childhood: current concepts

The juvenile idiopathic inflammatory myopathies are a group of rare, chronic, multisystem, autoimmune diseases associated with muscle weakness. This article reviews practical issues of relevance to pediatricians, including clinical presentation, differential diagnosis, investigation, therapy, and prognosis. The importance of early recognition and specialist involvement is emphasized.

Nailfold capillary density is importantly associated over time with muscle and skin disease activity in juvenile dermatomyositis

OBJECTIVES

To investigate the longitudinal association of nailfold capillary density (NCD; as a potential marker of activity) with various other clinical measures of disease activity and to evaluate baseline NCD as a predictor of disease outcome in children with JDM.

METHODS

Data from 809 clinic visits from 92 JDM patients were prospectively collected at each clinic visit over a time period of 5.5 years. The number of capillaries per millimetre at the distal nailfold was scored using a stereomicroscope. Disease activity was determined using the Childhood Myositis Assessment Scale (CMAS) and a modification of the validated disease activity score (DAS), which included three skin (SDAS) and three muscle (MDAS) criteria. An inception cohort subgroup (n=28) with a baseline visit at diagnosis was analysed separately.

RESULTS

Both DAS subscores, MDAS (β = -0.04437, P < 0.0001) and SDAS (β = -0.1589, P < 0.0001), as well as the CMAS (β = 0.02165, P < 0.0001) were significantly associated with loss of end row nailfold capillary over time (multiple regression mixed-model analysis). All patients in the inception subcohort showed a reduced baseline NCD (diagnostic sensitivity = 100%) that improved as the disease improved, but this did not predict longer term outcome or course of disease.

CONCLUSION

NCD is a marker of skin and muscle disease activity, and is an important measure of disease activity changes from visit to visit. Determination of capillary density may be useful when making treatment decisions. A decrease in NCD may be considered for inclusion in the diagnostic criteria due to its high sensitivity.

Long-term muscular outcome and predisposing and prognostic factors in juvenile dermatomyositis: A case-control study

OBJECTIVE

To compare muscle strength, physical health, and HLA-DRB1 allele carriage frequencies in patients with longstanding juvenile dermatomyositis (DM) with that of controls, and to determine the presence of and risk factors for muscle weakness and magnetic resonance imaging (MRI)-detected muscle damage in juvenile DM patients.

METHODS

Fifty-nine patients with juvenile DM examined a median of 16.8 years (range 2.0-38.1 years) after disease onset were compared with 59 age- and sex-matched controls. Muscle strength/endurance was measured by manual muscle testing (MMT) and the Childhood Myositis Assessment Scale (CMAS); health status was measured by the Short Form 36. HLA-DRB1 alleles were determined by sequencing in patients and 898 healthy controls. In patients, disease activity/damage was measured by the Disease Activity Score (DAS), Myositis Damage Index (MDI), Health Assessment Questionnaire/Childhood Health Assessment Questionnaire, and MRI scans of the thigh muscles. Early disease characteristics were obtained by chart review.

RESULTS

Patients had lower muscle strength/endurance (P < 0.001 for both) and physical health (P = 0.014) and increased HLA-DRB1*0301 (P = 0.01) and DRB1*1401 (P = 0.003) compared with controls. In patients, persistent muscle weakness was found in 42% with MMT (score <78) and in 31% with the CMAS (score <48), whereas MRI-detected muscle damage was found in 52%. Muscle weakness and MRI-detected muscle damage were predicted by MDI muscle damage and a high DAS 1 year postdiagnosis.

CONCLUSION

A median of 16.8 years after disease onset, juvenile DM patients were weaker than the controls; muscle weakness/reduced endurance was found in 31-42% of patients and MRI-detected muscular damage was found in 52% of patients. The outcomes were predicted by high disease activity and muscle damage present 1 year postdiagnosis.

Update on the assessment of children with juvenile idiopathic inflammatory myopathy

The availability of validated measurement tools to assess children with juvenile idiopathic inflammatory myopathies is critical to clinical care and to ongoing research into new therapeutic modalities and approaches. Recent work has led to the development of tools for assessment of muscle strength and physical function, skin disease, global disease activity and damage, extramuscular disease, and quality of life. Ongoing work is attempting to integrate these assessments into core sets and definitions of improvement and flare. Future work will refine these assessments and definitions and--where there are multiple choices--determine which tools constitute an optimal assessment.

The Paediatric Rheumatology International Trials Organisation provisional criteria for the evaluation of response to therapy in juvenile dermatomyositis

OBJECTIVE

To develop a provisional definition for the evaluation of response to therapy in juvenile dermatomyositis (DM) based on the Paediatric Rheumatology International Trials Organisation juvenile DM core set of variables.

METHODS

Thirty-seven experienced pediatric rheumatologists from 27 countries achieved consensus on 128 difficult patient profiles as clinically improved or not improved using a stepwise approach (patient's rating, statistical analysis, definition selection). Using the physicians' consensus ratings as the "gold standard measure," chi-square, sensitivity, specificity, false-positive and-negative rates, area under the receiver operating characteristic curve, and kappa agreement for candidate definitions of improvement were calculated. Definitions with kappa values >0.8 were multiplied by the face validity score to select the top definitions.

RESULTS

The top definition of improvement was at least 20% improvement from baseline in 3 of 6 core set variables with no more than 1 of the remaining worsening by more than 30%, which cannot be muscle strength. The second-highest scoring definition was at least 20% improvement from baseline in 3 of 6 core set variables with no more than 2 of the remaining worsening by more than 25%, which cannot be muscle strength (definition P1 selected by the International Myositis Assessment and Clinical Studies group). The third is similar to the second with the maximum amount of worsening set to 30%. This indicates convergent validity of the process.

CONCLUSION

We propose a provisional data-driven definition of improvement that reflects well the consensus rating of experienced clinicians, which incorporates clinically meaningful change in core set variables in a composite end point for the evaluation of global response to therapy in juvenile DM.

Clinical assessment in juvenile dermatomyositis

Juvenile dermatomyositis (JDM) is a multisystem inflammatory disease of unknown etiology that affects primarily the skin and muscles. Although the prognosis of JDM has improved considerably in the last three decades, a number of patients may develop irreversible damage due to the disease activity or its treatment. This damage may cause permanent disability and affect the quality of life of patients and their families. In the clinical management of patients with JDM, there is, therefore, the need of monitoring the level of disease activity, the accrual of organ damage, and the impact of the illness on patients' daily living. A reliable assessment of these different aspects of disease requires the availability of well-designed and standardized clinical tools. In the recent years, there has been increasing collaborative effort to devise new assessment measures and these measures have been included into disease activity and damage core sets of outcome variables that have been developed through international consensus. In addition, preliminary definitions of clinical improvement for patients with JDM and other idiopathic inflammatory myopathies have been created. In this review, the latest advances in the development of standardized instruments for the clinical assessment of JDM patients are illustrated and the recent international efforts that have led to the development of core sets of outcome measures and to preliminary definitions of improvement for JDM clinical trials are summarized.

Health-related quality of life of patients with juvenile dermatomyositis: results from the Pediatric Rheumatology International Trials Organisation multinational quality of life cohort study

OBJECTIVE

To investigate the health-related quality of life (HRQOL) change over time, as measured by the Child Health Questionnaire (CHQ), and its determinants in patients with active juvenile dermatomyositis (DM).

METHODS

We assessed patients with juvenile DM at both baseline and 6 months of followup, and healthy children age < or =18 years. Potential determinants of poor HRQOL included demographic data, physician's and parent's global assessments, muscle strength, functional ability as measured by the Childhood Health Assessment Questionnaire (C-HAQ), global disease activity assessments, and laboratory markers.

RESULTS

A total of 272 children with juvenile DM and 2,288 healthy children were enrolled from 37 countries. The mean +/- SD CHQ physical and psychosocial summary scores were significantly lower in children with juvenile DM (33.7 +/- 11.7 versus 54.6 +/- 4.1) than in healthy children (45.1 +/- 9.0 versus 52 +/- 7.2), with physical well-being domains being the most impaired. HRQOL improved over time in responders to treatment and remained unchanged or worsened in nonresponders. Both physical and psychosocial summary scores decreased with increasing levels of disease activity, muscle strength, and parent's evaluation of the child's overall well-being. A C-HAQ score >1.6 (odds ratio [OR] 5.06, 95% confidence interval [95% CI] 2.03-12.59), child's overall well-being score >6.2 (OR 5.24, 95% CI 2.27-12.10), and to a lesser extent muscle strength and alanine aminotransferase level were the strongest determinants of poor physical well-being at baseline. Baseline disability and longer disease duration were the major determinants for poor physical well-being at followup.

CONCLUSION

We found that patients with juvenile DM have a significant impairment in their HRQOL compared with healthy peers, particularly in the physical domain. Physical well-being was mostly affected by the level of functional impairment.

Long-term outcomes in juvenile dermatomyositis: How did we get here and where are we going?

Juvenile dermatomyositis (JDM) affects two to four children per million. Prior to treatment with corticosteroids, JDM had a high mortality rate (> 30%) and left 50% of those who survived with serious permanent impairments. After the introduction of corticosteroids, mortality rapidly dropped to less than 10%, and is currently reported to be less than 2% to 3%. Because most children now survive this illness, there is greater interest in long term outcomes. However, review of the literature shows while much is known about mortality, relatively little is known about long term outcomes such as physical function, quality of life, pain, educational and vocational achievement, patient satisfaction, and ongoing disease activity. Furthermore, the literature that has been published has not typically used the same outcomes making comparisons across studies difficult. Current efforts to identify key outcomes and validate measures for those outcomes will allow researchers in the future to provide this much needed information.

Recent advances in juvenile dermatomyositis

This paper reviews the knowledge we continue to gain in the areas of pathogenesis, evaluation of disease activity, and interventional strategies with regards to idiopathic inflammatory myositis. Potential new diagnostic criteria incorporate the use of magnetic resonance imaging and other imaging modalities along with the use of muscle biopsy pathologic features including that of immunologic markers. Specifically, this criterion reflects the upregulation of major histocompatibility complex molecules on muscle tissue during acute inflammation.

Inflammatory myopathies in children

Juvenile idiopathic inflammatory myopathies are rare conditions that are probably autoimmune in nature. Juvenile dermatomyositis (JDM) is the most common inflammatory myopathy. This article describes a recent patient who presented with typical JDM and uses her case to discuss aspects of the childhood inflammatory myopathies.