Summary Juvenile dermatomyositis, the most common inflammatory myopathy of childhood, is a rare systemic autoimmune vasculopathy that is characterised by weakness in proximal muscles and ...pathognomonic skin rashes. The length of time before the initiation of treatment affects presenting symptoms, laboratory measures, and pathophysiology. It also affects disease outcomes, including the development of pathological calcifications, which are associated with increased morbidity. Both genetic and environmental risk factors seem to have a role in the cause of juvenile dermatomyositis; HLA B8–DRB1*0301 ancestral haplotype is a strong immunogenetic risk factor, and antecedent infections and birth seasonality suggest that environmental stimuli might increase risk. Activation of dendritic cells with upregulation of genes induced by type-1 interferon (α) in muscle and peripheral blood seems to be central to disease pathogenesis. Treatment often includes combinations of corticosteroids, methotrexate, and other immunosuppressive agents. Disease outcome, if treatment is initiated early, is generally good. Randomised controlled trials are needed to define the most effective treatments.
Abstract Recently, there have been important advances in the understanding of the pathophysiologic features, assessment, and management of patients with a newly diagnosed idiopathic inflammatory ...myopathy (IIM). Myositis-specific autoantibodies have been identified to define patient subgroups and offer prognostic implications. Similarly, proinflammatory cytokines, such as interleukin 6 and type 1 interferon–dependent genes, may serve as potential biomarkers of disease activity in adult and juvenile patients with dermatomyositis (DM). Moreover, magnetic resonance imaging has become an important modality for the assessment of muscle inflammation in adult IIM and juvenile DM. Immune-mediated necrotizing myopathies also are being recognized as a subset of IIM triggered by medications such as statins. However, confusion exists regarding effective management strategies for patients with IIM because of the lack of large-scale, randomized, controlled studies. This review focuses primarily on our current management and treatment algorithms for IIM including the care of pediatric patients with juvenile DM. For this review, we conducted a search of PubMed and MEDLINE for articles published from January 1, 1970, to December 1, 2011, using the following search terms: idiopathic inflammatory myopathies, dermatomyositis, polymyositis, juvenile dermatomyositis, sporadic inclusion body myositis, inclusion body myositis, inflammatory myositis, myositis, myopathies, pathogenesis, therapy, and treatment. Studies published in English were selected for inclusion in our review as well as additional articles identified from bibliographies.
To develop and validate new classification criteria for adult and juvenile idiopathic inflammatory myopathies (IIM) and their major subgroups.
Candidate variables were assembled from published ...criteria and expert opinion using consensus methodology. Data were collected from 47 rheumatology, dermatology, neurology and paediatric clinics worldwide. Several statistical methods were used to derive the classification criteria.
Based on data from 976 IIM patients (74% adults; 26% children) and 624 non-IIM patients with mimicking conditions (82% adults; 18% children), new criteria were derived. Each item is assigned a weighted score. The total score corresponds to a probability of having IIM. Subclassification is performed using a classification tree. A probability cut-off of 55%, corresponding to a score of 5.5 (6.7 with muscle biopsy) 'probable IIM', had best sensitivity/specificity (87%/82% without biopsies, 93%/88% with biopsies) and is recommended as a minimum to classify a patient as having IIM. A probability of ≥90%, corresponding to a score of ≥7.5 (≥8.7 with muscle biopsy), corresponds to 'definite IIM'. A probability of <50%, corresponding to a score of <5.3 (<6.5 with muscle biopsy), rules out IIM, leaving a probability of ≥50 to <55% as 'possible IIM'.
The European League Against Rheumatism/American College of Rheumatology (EULAR/ACR) classification criteria for IIM have been endorsed by international rheumatology, dermatology, neurology and paediatric groups. They employ easily accessible and operationally defined elements, and have been partially validated. They allow classification of 'definite', 'probable' and 'possible' IIM, in addition to the major subgroups of IIM, including juvenile IIM. They generally perform better than existing criteria.
Objective
To develop and validate new classification criteria for adult and juvenile idiopathic inflammatory myopathies (IIM) and their major subgroups.
Methods
Candidate variables were assembled ...from published criteria and expert opinion using consensus methodology. Data were collected from 47 rheumatology, dermatology, neurology, and pediatric clinics worldwide. Several statistical methods were utilized to derive the classification criteria.
Results
Based on data from 976 IIM patients (74% adults; 26% children) and 624 non‐IIM patients with mimicking conditions (82% adults; 18% children), new criteria were derived. Each item is assigned a weighted score. The total score corresponds to a probability of having IIM. Subclassification is performed using a classification tree. A probability cutoff of 55%, corresponding to a score of 5.5 (6.7 with muscle biopsy) “probable IIM,” had best sensitivity/specificity (87%/82% without biopsies, 93%/88% with biopsies) and is recommended as a minimum to classify a patient as having IIM. A probability of ≥90%, corresponding to a score of ≥7.5 (≥8.7 with muscle biopsy), corresponds to “definite IIM.” A probability of <50%, corresponding to a score of <5.3 (<6.5 with muscle biopsy), rules out IIM, leaving a probability of ≥50–<55% as “possible IIM.”
Conclusion
The European League Against Rheumatism/American College of Rheumatology (EULAR/ACR) classification criteria for IIM have been endorsed by international rheumatology, dermatology, neurology, and pediatric groups. They employ easily accessible and operationally defined elements, and have been partially validated. They allow classification of “definite,” “probable,” and “possible” IIM, in addition to the major subgroups of IIM, including juvenile IIM. They generally perform better than existing criteria.
Objective
To identify the clinical and laboratory predictors of clinical improvement in a cohort of myositis patients treated with rituximab.
Methods
We analyzed data for 195 patients with myositis ...(75 with adult polymyositis PM, 72 with adult dermatomyositis DM, and 48 with juvenile DM) in the Rituximab in Myositis trial. Clinical improvement was defined as 20% improvement in at least 3 of the following 6 core set measures of disease activity: physician's and patient's/parent's global assessment of disease activity, manual muscle testing, physical function, muscle enzymes, and extramuscular disease activity. We analyzed the association of the following baseline variables with improvement: myositis clinical subgroup, demographics, myositis damage, clinical and laboratory parameters, core set measures, rituximab treatment, and myositis autoantibodies (antisynthetase, anti–Mi‐2, anti–signal recognition particle, anti–transcription intermediary factor 1γ TIF‐1γ, anti‐MJ, other autoantibodies, and no autoantibodies). All measures were univariately assessed for association with improvement using time‐to‐event analyses. A multivariable time‐dependent proportional hazards model was used to evaluate the association of individual predictive factors with improvement.
Results
In the final multivariable model, the presence of an antisynthetase, primarily anti–Jo‐1 (hazard ratio HR 3.08, P < 0.01), anti–Mi‐2 (HR 2.5, P < 0.01), or other autoantibody (HR 1.4, P = 0.14) predicted a shorter time to improvement compared to the absence of autoantibodies. A lower physician's global assessment of damage (HR 2.32, P = 0.02) and juvenile DM (versus adult myositis) (HR 2.45, P = 0.01) also predicted improvement. Unlike autoantibody status, the predictive effect of physician's global assessment of damage and juvenile DM diminished by week 20. Rituximab treatment did not affect these associations.
Conclusion
Our findings indicate that the presence of antisynthetase and anti–Mi‐2 autoantibodies, juvenile DM subset, and lower disease damage strongly predict clinical improvement in patients with refractory myositis.
Gene expression profiling and protein studies of the type I interferon pathway have revealed important insights into the disease process in adult and juvenile dermatomyositis. The most prominent and ...consistent feature has been a characteristic whole blood gene signature indicating upregulation of the type I interferon pathway. Upregulation of the type I interferon protein signature has added additional markers of disease activity and insight into the pathogenesis of the disease.
The aim was to assess the efficacy of rituximab for the cutaneous manifestations of adult DM and JDM.
Patients with refractory adult DM (n = 72) and JDM (n = 48) were treated with rituximab in a ...randomized placebo-phase-controlled trial either rituximab early drug (week 0/1) or rituximab late arms (week 8/9), such that all subjects received study drug. Stable concomitant therapy was allowed. Cutaneous disease activity was assessed using the Myositis Disease Activity Assessment Tool, which grades cutaneous disease activity on a visual analog scale. A myositis damage assessment tool, termed the Myositis Damage Index, was used to assess cutaneous damage. Improvement post-rituximab was evaluated in individual rashes as well as in cutaneous disease activity and damage scores. The χ
test, Student's paired t-test and Wilcoxon test were used for analysis.
There were significant improvements in cutaneous disease activity from baseline to the end of the trial after rituximab administration in both adult DM and JDM subsets. The cutaneous visual analog scale activity improved in adult DM (3.22-1.72, P = 0.0002) and JDM (3.26-1.56, P <0.0001), with erythroderma, erythematous rashes without secondary changes of ulceration or necrosis, heliotrope, Gottron sign and papules improving most significantly. Adult DM subjects receiving rituximab earlier in the trial demonstrated a trend for faster cutaneous response (20% relative improvement from baseline) compared with those receiving B cell depletion later (P = 0.052).
Refractory skin rashes in adult DM and JDM showed improvement after the addition of rituximab to the standard therapy in a clinical trial.
Update on outcome assessment in myositis Rider, Lisa G; Aggarwal, Rohit; Machado, Pedro M ...
Nature reviews. Rheumatology,
05/2018, Letnik:
14, Številka:
5
Journal Article
Recenzirano
Odprti dostop
The adult and juvenile myositis syndromes, commonly referred to collectively as idiopathic inflammatory myopathies (IIMs), are systemic autoimmune diseases with the hallmarks of muscle weakness and ...inflammation. Validated, well-standardized measures to assess disease activity, known as core set measures, were developed by international networks of myositis researchers for use in clinical trials. Composite response criteria using weighted changes in the core set measures of disease activity were developed and validated for adult and juvenile patients with dermatomyositis and adult patients with polymyositis, with different thresholds for minimal, moderate and major improvement in adults and juveniles. Additional measures of muscle strength and function are being validated to improve content validity and sensitivity to change. A health-related quality of life measure, which incorporates patient input, is being developed for adult patients with IIM. Disease state criteria, including criteria for inactive disease and remission, are being used as secondary end points in clinical trials. MRI of muscle and immunological biomarkers are promising approaches to discriminate between disease activity and damage and might provide much-needed objective outcome measures. These advances in the assessment of outcomes for myositis treatment, along with collaborations between international networks, should facilitate further development of new therapies for patients with IIM.
IMPORTANCE: Mutations in the CERC1 gene associated with deficiency in the ADA2 protein (DADA2) have been implicated in the pathogenesis of cutaneous polyarteritis nodosa (cPAN) and early-onset ...vasculopathy. DADA2 is not only limited to cPAN and vasculopathy but also includes immunodeficiency that affects several cellular compartments, including B cells; however, some patients appear to have a more indolent, skin-limited disease. OBSERVATIONS: In this report, we describe 2 white siblings (female and male) with a history of cPAN with DADA2 as a result of novel compound heterozygous mutations inherited in trans in the CECR1 gene (c.37_39del p.K13del and c.984C>A p.N328K). The onset of disease was earlier in the female sibling than the male sibling although both were diagnosed as having cPAN in early childhood. The disease is associated with a more significant immunodeficiency and other systemic symptoms in the female than the male sibling. CONCLUSIONS AND RELEVANCE: These findings suggest a genetic cause of cPAN in some patients. Therefore, DADA2 should be considered in patients with cPAN, specifically in those whose conditions are diagnosed at an early age, regardless of their ethnicity, presence or absence of systemic symptoms, or a family history of the disease.
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