Utility of anti-melanoma differentiation-associated gene 5 antibody measurement in identifying patients with dermatomyositis and a high risk for developing rapidly progressive interstitial lung disease: a review of the literature and a meta-analysis

Case Report: Treatment of Anti-MDA5-Positive Amyopathic Dermatomyositis Accompanied by a Rapidly Progressive Interstitial Lung Diseases With Methylprednisolone Pulse Therapy Combined With Cyclosporine A and Hydroxychloroquine

Introduction: Patients with anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive amyopathic dermatomyositis (ADM) often develop rapidly progressive interstitial lung diseases (RP-ILD), with poor treatment success. Many studies have shown that this is the main cause of death in patients with anti-MDA5 antibody-positive ADM. Case Presentation: A 37-years-old woman developed a cough, shortness of breath, and a rash on both hands, which resembled Gottron's signs. Upon laboratory examination, the results were as follows: antinuclear antibody (ANA) positive; anti-Ro52 antibody positive; and anti-MDA5 antibody positive. Pulmonary high-resolution CT (HRCT) scan showed pulmonary interstitial inflammatory changes, and mediastinal and subcutaneous emphysema. She was finally diagnosed with anti-MDA5 antibody-positive ADM accompanied by RP-ILD. She was first given high-dose-steroid pulse therapy with methylprednisolone (500 mg per day for 3 days) followed by methylprednisolone (40 mg, daily), cyclosporine A (100 mg, twice per day), and hydroxychloroquine (200 mg, twice per day). Since her discharge from our hospital in March of 2018, she has maintained the methylprednisolone therapy (tapered to 10 mg daily), cyclosporine A (100 mg, twice per day), and hydroxychloroquine (200 mg, twice per day). Outcomes: Pulmonary HRCT scans taken on 4, 9, and 26 months after her discharge from our hospital showed that the interstitial pneumonitis had significantly improved and that mediastinal and subcutaneous emphysema had been gradually absorbed. The patient can now participate in regular work and activities of daily living. Conclusion: The treatment of methylprednisolone pulse therapy combined with cyclosporine A and hydroxychloroquine may be an option for the RP-ILD accompanied by anti-MDA-positive ADM. After the acute phase, this combination therapy strategy is helpful to the disease control of patients.

Iacta Alea Est: The Inexorable Advance of Tofacitinib in the Treatment of Dermatomyositis-Associated Rapidly Progressive Interstitial Lung Disease. A Case Report

Rapidly progressive interstitial lung disease is typically associated with clinically amyopathic dermatomyositis and the anti-melanoma differentiation associated gene 5 antibody, a condition with high mortality and resistance to classic immunosuppression. Recent reports have described the efficacy of the Janus kinase inhibitor tofacitinib in the treatment of rapidly progressive interstitial lung disease in anti-melanoma differentiation associated gene 5 antibody-positive clinically amyopathic dermatomyositis. It is uncertain, however, whether tofacitinib alters the course of rapidly progressive interstitial lung disease in other variants of dermatomyositis that are unrelated to the anti-melanoma differentiation associated gene 5 antibody and whether the early addition of the anti-fibrotic tyrosine kinase inhibitor nintedanib interferes with the development of fibrosis. To answer these questions, we present and discuss the case of an elderly woman who presented with a flare of dermatomyositis sine myositis. Based upon the detection of anti-Jo-1 antibodies and the absence of anti-melanoma differentiation associated gene 5 antibodies, anti-synthetase syndrome was diagnosed. While the cutaneous manifestations quickly resolved with prednisone, azathioprine and tacrolimus, the respiratory function paradoxically and rapidly deteriorated, and invoked the use of tofacitinib. Markedly raised ferritin levels and a severe numerical deficiency of circulating natural killer cells paralleled the acute lung inflammation, which was reflected by ¹⁸F-fluorodeoxyglucose hypermetabolism on positron emission tomography/CT. Tofacitinib lead to a prompt clinical recovery, with a reduction in oxygen requirement, correction of hyperferritinemia, reversal of the natural killer cell deficiency, and a decrease in ¹⁸F-fluorodeoxyglucose uptake in the affected lung segments. Subsequently, nintedanib was added at a point in time when inflammation subsided. Apart from cytomegalovirus reactivation no adverse events occurred. In conclusion, tofacitinib reversed the pronounced inflammatory component of anti-Jo-1 antibody-positive, anti-melanoma differentiation associated gene 5 antibody-negative rapidly progressive interstitial lung disease, confirming that Janus kinase signaling pathways are critically involved in the pathogenesis of rapidly progressive interstitial lung disease, apparently independently of the targeted autoantigen. Although some improvement in pulmonary function was observed, it seems premature to conclusively judge on reversibility or prevention of pulmonary fibrosis by pairing both kinase inhibitors for which an extended follow-up and ideally, prospective and controlled studies are needed.

Predictors of Poor Outcome of Anti-MDA5-Associated Rapidly Progressive Interstitial Lung Disease in a Chinese Cohort with Dermatomyositis

Objective

Antimelanoma differentiation-associated protein 5 (anti-MDA5) autoantibody has been reported in dermatomyositis (DM) to be associated with rapidly progressive interstitial lung disease (RP-ILD). Our study is aimed at determining the clinical characteristics and prognostic factors underpinning anti-MDA5-associated RP-ILD.

Methods

Patients with anti-MDA5-associated DM (aMDA5-DM) were identified at the Peking University People's Hospital. The presence of anti-MDA5 antibody was determined by immunoblotting. Kaplan-Meier, chi-square test, univariate, and multivariate data analyses were used.

Results

Out of 213 patients with DM and clinically amyopathic dermatomyositis (CADM), 20.7% (44/213) of patients were identified as aMDA5-DM. Amongst the aMDA5-DM patients, 63.6% (28/44) were identified as having anti-MDA5-associated RP-ILD. During the follow-up, 32.1% (9/28) of patients with anti-MDA5-associated RP-ILD died of respiratory failure. We identified older age and periungual erythema as two independent risk factors for RP-ILD mortality. Age ≥ 57 years at disease onset was significantly associated with poor survival (P = 0.02) in patients with anti-MDA5-associated RP-ILD, while patients with periungual erythema had a better survival rate than those without periungual erythema (P < 0.05).

Conclusions

Anti-MDA5-associated RP-ILD is significantly associated with poor survival rates in DM/CADM patients. More effective intervention should be administered to anti-MDA5-associated RP-ILD patients, especially to senior patients and those without periungual erythema.

Predictive Features and Clinical Presentation of Interstitial Lung Disease in Inflammatory Myositis

Interstitial lung disease (ILD) represents one of the most severe extra-muscular features of idiopathic inflammatory myositis (IIM). We aimed to identify any clinical and serological predictors of ILD in a monocentric cohort of 165 IIM patients.

ILD+ patients were defined as having restrictive impairment in lung function tests and signs of ILD at chest high-resolution computed tomography (HRCT). Available HRCT images were centralized and classified in different ILD patterns: non-specific interstitial pneumonia (NSIP), organizing pneumonia (OP), usual interstitial pneumonia-like (UIP), indeterminate for UIP, and interstitial lung abnormalities (ILA). Lung function test data were recorded at onset, at 1 and 5 years after ILD diagnosis.

ILD was found in 52 IIM patients (31.5%): 46.2% was affected by anti-synthetase syndrome (ARS), 21% by polymyositis (PM), 19% by dermatomyositis (DM), and 13.5% by overlap myositis. Most of ILD+ showed NSIP (31.9%), OP (19%), indeterminate for UIP (19%), and UIP (12.8%) patterns. At multivariate analysis, ILD was predicted by anti-Ro52 (p: 0.0026) and dyspnea (p: 0.015) at IIM onset. Most of ILD onset within is 12 months after IIM. In five cases, ILD occurs after 12 months since IIM diagnosis: these patients more frequently show dry cough and anti-Ku antibodies. Anti-Ro52 + ILD patients showed a significant increase of DLCO at 1 and 5 years of follow-up, compared with anti-Ro52 negative cases.

ILD occurs in about one third of IIM and was predicted by dyspnea at onset and anti-Ro52 antibodies. Anti-Ro52 defines a subgroup of ILD showing a significant improvement of DLCO during follow-up.

This retrospective study has been approved by local ethic committee (ASST-Spedali Civili of Brescia, Italy); protocol number: NP3511

[Fatal interstitial lung disease and pneumocystis during dermatomyositis associated with anti-MDA5 antibodies]

BACKGROUND

Dermatomyositis (DM) in an auto-immune inflammatory myopathy with skin lesions, and, occasionally, organ involvement. Herein, we report a case of DM during anti-MDA5 antibody therapy associated with interstitial lung disease (ILD) and pneumocystosis.

PATIENTS AND METHODS

A 64-year-old woman was hospitalized for impairment of her general health and skin lesions. Dermatological examination revealed classic signs of DM associated with hyperkeratotic papules on the palm creases. This led us to suspect DM with anti-MDA5 antibodies, which was subsequently confirmed by immunologic tests. We also noted dysphonia, exertional dyspnea and proximal muscles weakness. Despite early corticosteroid therapy, combined later with azathioprine, the patient's dyspnoea worsened; one month later, sudden pulmonary decompensation resulted in her admission to intensive care. A chest scan showed evidence of ILD and infectious signs, and the bronchoalveolar lavage was positive for Pneumocystisjiroveci. Despite treatment of this opportunist infection with cotrimoxazole and intensified immunosuppression, the patient died in intensive care.

DISCUSSION

Anti-MDA5 antibodies are associated with a specific clinical phenotype and a high degree of risk that should alert the dermatologist to the high likelihood of ILD having a poor prognosis. Associated clinical signs are erythematous, hyperkeratotic or ulcerated papules on the palm creases, as well as fingertip or periungual ulcerations or digital necrosis. This situation is associated with a high risk of pneumocystosis. However, no recommendations concerning prophylaxis are currently available.

Plasma homocysteine levels are positively associated with interstitial lung disease in dermatomyositis patients with anti-aminoacyl-tRNA synthetase antibody

Homocysteine is a sulfhydryl-containing amino acid that is derived from dietary methionine, and there has been increasing evidence that elevated plasma homocysteine levels are associated with increased risk of central and peripheral vascular disorders, including carotid, coronary and peripheral arterial diseases, and Raynaud's phenomenon. Recently, associations of plasma homocysteine levels with autoimmune diseases such as systemic lupus erythematodes and systemic sclerosis have been reported. However, no study analyzed the association between plasma homocysteine levels and dermatomyositis (DM). The objective of this study was to examine plasma homocysteine levels and their clinical associations in patients with DM. Plasma homocysteine levels in 28 Japanese patients with DM and 22 healthy controls were examined. We found that the plasma homocysteine levels in DM patients were significantly higher than those in healthy individuals (15.8 ± 1.1 vs 8.5 ± 0.5 µmol/L, P < 0.01). Presence of mechanic's hand, complication of interstitial lung disease (ILD), high serum Krebs von den Lungen-6 (KL-6), surfactant protein-D and creatine kinase levels, and anti-aminoacyl-tRNA synthetase (ARS) antibody (Ab) positivity were significantly more prevalent among DM patients with elevated plasma homocysteine levels. The plasma homocysteine levels in DM patients with mechanic's hand, ILD and anti-ARS Ab were significantly higher than those in DM without those features. Furthermore, the plasma homocysteine levels were positively correlated with serum KL-6 levels. These results suggest that the pathogenesis of elevated plasma homocysteine levels may be associated with ILD in DM patients, especially with anti-ARS Ab, and further examination is required.

MDA-5 dermatomyositis complicated by interstitial lung disease and cutaneous ulcers: successful treatment with corticosteroids, mycophenolate mofetil and intravenous immunoglobulin

Antimelanoma differentiation-associated gene 5 (MDA-5) dermatomyositis is a subtype of dermatomyositis that is associated with rapidly progressive interstitial lung disease (RP-ILD), as well as with a variety of cutaneous manifestations. Patients with MDA-5 dermatomyositis tend to have a poor prognosis that is often attributed to the high rates of concurrent RP-ILD. Given the severity of disease, early diagnosis and aggressive management is pivotal. We present a case of a 40-year-old woman diagnosed with MDA-5 dermatomyositis who presented with weakness, painful cutaneous ulcerations and interstitial lung disease. She was treated with monthly intravenous Ig (IVIg), weight-based prednisone and mycophenolate mofetil (MMF). After approximately 2 years of treatment, her interstitial lung disease remains stable and she has had significant improvement in weakness and cutaneous ulcerations. Our case provides evidence for early and aggressive treatment of MDA-5 dermatomyositis with a combination of weight-based prednisone, MMF and IVIg.

Impact of adding tacrolimus to initial treatment of interstitial pneumonitis in polymyositis/dermatomyositis: a single-arm clinical trial

Objective

Interstitial pneumonia is common and has high short-term mortality in patients with PM and DM despite glucocorticoid (GC) treatment. Retrospective studies suggested that the early use of immunosuppressive drugs with GCs might improve its short-term mortality.

Methods

A multicentre, single-arm, 52-week-long clinical trial was performed to test whether the initial combination treatment with tacrolimus (0.075 mg/kg/day, adjusted for the target whole-blood trough levels between 5 and 10 ng/ml) and GCs (0.6–1.0 mg/kg/day of prednisolone followed by a slow taper) improves short-term mortality of PM/DM-interstitial pneumonia patients. The primary outcome was overall survival. We originally intended to compare, by using propensity-score matching, the outcome data of clinical trial patients with that of historical control patients who were initially treated with GCs alone.

Results

The 52-week survival rate with the combination treatment (N = 26) was 88.0% (95% CI, 67.3, 96.0). Safety profiles of the combination treatment were consistent with those known for tacrolimus and high-dose GCs individually. Serious adverse events occurred in 11 patients (44.0%), which included four opportunistic infections. Only 16 patients, including only 1 deceased patient, were registered as historical controls, which precluded meaningful comparative analysis against the clinical trial patients.

Conclusion

Our study provided findings which suggest that initial treatment with tacrolimus and GCs may improve short-term mortality of PM/DM-interstitial pneumonia patients with manageable safety profiles. This was the first prospective clinical investigation conducted according to the Good Clinical Practice Guideline of the International Conference on Harmonization for the treatment of this potentially life-threatening disease.

Trial registration

ClinicalTrials.gov, http://clinicaltrials.gov, NCT00504348.

Anti-MDA-5 antibody-positive clinically amyopathic dermatomyositis with rapidly progressive interstitial lung disease treated with therapeutic plasma exchange: A case series

We present six cases of antimelanoma differentiation-associated gene 5 antibody (anti-MDA5-Ab)-positive clinically amyopathic dermatomyositis (CADM) with rapidly progressive interstitial lung disease (RP-ILD), which is known to have a poor prognosis. The outcomes of these cases are described after treatment with therapeutic plasma exchange (TPE). Clinical and therapeutic data for patients with CADM with RP-ILD were collected retrospectively from medical records. All six patients received early intensive care including high-dose corticosteroids, intravenous cyclophosphamide, and a calcineurin inhibitor, but lung disease and hypoxia became more severe. TPE was performed over a median of 9.5 sessions (range 3-14) per patient, and the median duration from admission to TPE was 23 days. Three patients received combined direct hemoperfusion using a polymyxin B-immobilized fiber column (PMX-DHP) therapy on successive days to manage acute respiratory failure. Four patients survived and two died due to respiratory failure. In the survival cases, ferritin decreased, and ferritin and KL-6 were lower at diagnosis. The patients who died had a higher alveolar-arterial oxygen difference and more severe lung lesions at the time of initiation of TPE. These findings indicate that a combination of conventional therapy and TPE may be useful for improvement of the prognosis of CADM with RP-ILD at the early stage of onset.

Therapeutic plasma exchange for clinically amyopathic dermatomyositis (CADM) associated with rapidly progressive interstitial pneumonia

BACKGROUND

Patients with clinically amyopathic dermatomyositis (CADM) with anti-melanoma differentiation-associated gene 5 antibody (anti-MDA5 Ab) frequently develop rapidly progressive interstitial pneumonia (RPIP), often with fatal outcomes. Therapeutic plasma exchange (TPE) has been reported as effective against CADM-RPIP refractory to conventional immunosuppressive therapy. However, the detailed mechanisms by which TPE improves disease activity of CADM-RPIP remain unclear.

AIM

To elucidate the clinical and demographic characteristics of patients with anti-MDA5 Ab-positive CADM-RPIP treated with TPE and to analyze changes in laboratory findings before, during, and after TPE.

MATERIALS & METHODS

Patients hospitalized for CADM-RPIP and treated with TPE in 2017 and 2018 were analyzed retrospectively.

RESULTS

Three patients were successfully treated with TPE, with good tolerance. Anti-MDA5 Ab titers decreased significantly over the course of TPE.

CONCLUSION

We emphasize that TPE could represent an effective treatment option for CADM-RPIP refractory to traditional therapy. Removal of anti-MDA5 Ab and other pathogenic factors may facilitate favorable outcomes.

Demographic and clinical characteristics of cytomegalovirus reactivation in dermatomyositis

Dermatomyositis (DM) patients are known to have various infectious complications, such as cytomegalovirus (CMV) reactivation, due to immune dysfunction caused by DM itself and immunosuppressants used for treatment. Although CMV reactivation has been known to be a major cause of mortality in immunocompromised hosts, there has not been sufficient study of CMV reactivation in DM patients. The objective of this study was to examine the frequency of CMV reactivation in DM patients and to investigate risk factors potentially associated with development of CMV reactivation. We analyzed 52 Japanese DM patients, and CMV reactivation was observed in 21 (40.4%). The mean duration from the initiation of prednisolone (PSL) to the diagnosis of CMV reactivation was 6.1 ± 0.5 weeks. The total amount of oral PSL before the diagnosis of CMV reactivation was 2000.3 ± 169.3 mg. Using a univariate analysis, we found that the prevalence of interstitial lung disease and the frequency of diabetes mellitus complications in DM patients with CMV reactivation was significantly higher than that in DM patients without CMV. We identified that low lymphocytes (<900/μL) in DM patients was significantly associated with developing CMV reactivation. The use of immunosuppressants, including tacrolimus, cyclosporin and/or i.v. cyclophosphamide, was significantly associated with CMV reactivation in DM patients. Using a multivariate analysis, low lymphocytes at the time of DM diagnosis was found to be a risk factor for CMV reactivation. In addition, there was a tendency for diabetes mellitus to be a risk factor for CMV reactivation in DM patients. There was no difference in the prognosis for those with or without CMV reactivation in this study. These results suggest that in the DM patients with risk factors such as low lymphocytes and diabetes mellitus complications, regularly monitoring CMV reactivation and adequate treatment with antiviral agents may be necessary to prevent a poor prognosis.

Recommendations for the treatment of anti-melanoma differentiation-associated gene 5-positive dermatomyositis-associated rapidly progressive interstitial lung disease

OBJECTIVES

The study aimed to develop evidence-based recommendations for the treatment of rapidly progressive interstitial lung disease (RPILD) associated with the anti-Melanoma Differentiation-Associated Gene 5-positive dermatomyositis (DM) syndrome.

METHODS

The task force comprised an expert panel of specialists in rheumatology, intensive care medicine, pulmonology, immunology, and internal medicine. The study was carried out in two phases: identifying key areas in the management of DM-RPILD syndrome and developing a set of recommendations based on a review of the available scientific evidence. Four specific questions focused on different treatment options were identified. Relevant publications in English, Spanish or French up to April 2018 were searched systematically for each topic using PubMed (MEDLINE), EMBASE, and Cochrane Library (Wiley Online). The experts used evidence obtained from these studies to develop recommendations.

RESULTS

A total of 134 studies met eligibility criteria and formed the evidentiary basis for the recommendations regarding immunosuppressive therapy and complementary treatments. Overall, there was general agreement on the initial use of combined immunosuppressive therapy. Combination of high-dose glucocorticoids and calcineurin antagonists with or without cyclophosphamide is the first choice. In the case of calcineurin antagonist contraindication or treatment failure, switching or adding other immunosuppressants may be individualized. Plasmapheresis, polymyxin B hemoperfusion and/or intravenous immunoglobulins may be used as rescue options. ECMO should be considered in life-threatening situations while waiting for a clinical response or as a bridge to lung transplant.

CONCLUSIONS

Thirteen recommendations regarding the treatment of the anti-MDA5 positive DM-RPILD were developed using research-based evidence and expert opinion.

Anti-MDA5-associated dermatomyositis

Anti-MDA5-associated dermatomyositis (MDA5-associated DM) is an uncommon presentation of idiopathic inflammatory myositis, typically amyopathic, associated with rapidly progressive, treatment refractory interstitial lung disease and poor prognosis, particularly in patients with concomitant rapidly progressive interstitial lung disease (RP-ILD). We report two cases of MDA5-associated DM with fatal outcome in one of the patients, despite 'aggressive triple therapy' for RP-ILD.

Clinical features of dermatomyositis associated with anti-MDA5 antibodies by age

OBJECTIVES

Anti-melanoma differentiation-associated gene 5 (MDA5) autoantibody-positive and age at onset ≥60 years are poor prognosis factors in polymyositis (PM) and dermatomyositis (DM) associated with interstitial lung disease (ILD) among Japanese patients. However, the influence of age on the clinical features of anti-MDA5 autoantibody-positive patients with DM remains unclear.

METHODS

We retrospectively examined 40 patients with DM and anti-MDA5 autoantibodies according to age. We compared patients aged <60 and ≥60 years with respect to clinical features including laboratory test findings, high-resolution lung computed tomography data, treatment content, and complications such as infections and prognosis. We also examined clinical features between surviving and deceased patients in the older patient group.

RESULTS

Of 40 enrolled patients, 13 were classified as old and 27 as young. Older patients had significantly fewer clinical symptoms including arthralgia/arthritis (p < .01), skin ulceration (p = .02), and higher mortality than younger patients (p = .02) complicated with rapidly progressive ILD (RP-ILD), combination immunosuppressive therapy, and strictly controlled infections.

CONCLUSION

Clinical features and mortality of anti-MDA5 autoantibody-positive DM patients were influenced by age. Patients aged ≥60 years had a worse prognosis, and combination immunosuppressive therapy was often ineffective for RP-ILD in older patients.

Treatment of the Connective Tissue Disease-Related Interstitial Lung Diseases: A Narrative Review

Interstitial lung disease (ILD) is a frequent complication of patients with connective tissue disease (CTD) and significantly affects morbidity and mortality. Disease course may vary from stable or mildly progressive to more severe, with rapid loss of lung function. We conducted a search of PubMed (National Library of Medicine) and the Web of Science Core Collection using the key words lung, pulmonary, pneumonia, pneumonitis, and alveolar and subtypes of CTD. All clinical studies from January 1, 1980, through September 1, 2018, were reviewed for descriptions of specific therapies and their efficacy or safety and were categorized as controlled interventional trials, observational prospective or retrospective cohort studies, case series (>5 patients), and case reports (<5 patients). Low-quality reports (<5 patients) before 2000, reviews, editorials, popular science papers, and letters to the editor without complete descriptions of the therapies used or their outcomes were excluded. Directed therapy for CTD-ILD is dominated by empirical use of immunosuppressive agents, with the decision to treat, treatment choice, and treatment duration limited to cases and cohort observations. Only a few higher-level controlled studies were available specifically in scleroderma-related ILD. We summarize herein for the clinician the published treatment scope and experience, highlighted clinical response, and common adverse reactions for the management of CTD-ILD.

Combined immunosuppressive therapy provides favorable prognosis and increased risk of cytomegalovirus reactivation in anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody (Ab) is myositis-specific autoantibody associated with rapidly progressive interstitial lung disease (ILD) and poor prognosis. In this retrospective observational study, we aimed to verify the efficacy and safety of introducing combined immunosuppressive therapy for anti-MDA5 Ab-positive dermatomyositis (DM) from their early stage. We recruited all Japanese patients diagnosed with DM in our clinic between January 2011 and October 2018, who had anti-MDA5 Ab, anti-aminoacyl transfer RNA synthetase Ab or anti-transcriptional intermediary factor 1-γ Ab. Combined immunosuppressive therapy was defined as combination of systemic corticosteroids, i.v. cyclophosphamide and tacrolimus. The difference of clinical features among the three groups was analyzed by multiple comparison analysis. The longitudinal change of the measurements from baseline was examined by Wilcoxon signed-rank test. Association between therapeutic regimens and adverse events was examined by logistic regression analysis. As a result, combined immunosuppressive therapy was most frequently used in the anti-MDA5 Ab-positive group, which significantly improved their forced vital capacity of the lung. Interval time since initial visit until starting treatment was the shortest in the anti-MDA5 Ab-positive group. There was no significant difference in the incidence of death and recurrence among the three groups. Cytomegalovirus reactivation was most common in the anti-MDA5 Ab-positive group, associated with combined immunosuppressive therapy. Collectively, early introduction of combined immunosuppressive therapy was effective for DM patients with anti-MDA5 Ab. At the same time, clinicians should be aware of the risk of cytomegalovirus reactivation during the treatment.

Multicenter Prospective Study of the Efficacy and Safety of Combined Immunosuppressive Therapy With High-Dose Glucocorticoid, Tacrolimus, and Cyclophosphamide in Interstitial Lung Diseases Accompanied by Anti-Melanoma Differentiation-Associated Gene 5-Positive Dermatomyositis

OBJECTIVE

Interstitial lung disease (ILD) accompanied by anti-melanoma differentiation-associated gene 5 (anti-MDA-5)-positive dermatomyositis (DM) is often rapidly progressive and associated with poor prognosis. Because there is no established treatment, we undertook this study to prospectively evaluate the efficacy and safety of a combined immunosuppressive regimen for anti-MDA-5-positive DM patients with ILD.

METHODS

Adult Japanese patients with new-onset anti-MDA-5-positive DM with ILD (n = 29) were enrolled at multiple study centers from 2014 to 2017. They were treated with a regimen of high-dose glucocorticoids (GCs), tacrolimus, and intravenous cyclophosphamide (IV CYC). Plasmapheresis was used if a patient's condition worsened after the regimen started. The primary end point was 6-month survival, which was compared between this group of patients and a historical control group (n = 15) consisting of anti-MDA-5-positive DM patients with ILD who received step-up treatment (high-dose GC and stepwise addition of immunosuppressant). Secondary end points were 12-month survival rate, adverse events, and changes in laboratory data.

RESULTS

The combined immunosuppressive regimen group showed significantly higher 6-month survival rates than the step-up treatment group (89% versus 33%; P < 0.0001). Over a period of 52 weeks, improvements in anti-MDA-5 titers, serum ferritin levels, vital capacity, and chest high-resolution computed tomography scores were observed. The combined immunosuppressive regimen group received IV CYC nearly 20 days earlier with shorter intervals and tended to receive plasmapheresis more often than patients undergoing step-up treatment. Cytomegalovirus reactivation was frequently observed over 52 weeks.

CONCLUSION

A combined immunosuppressive regimen is effective for anti-MDA-5-positive DM patients with ILD. Plasmapheresis can be used for additional effect in intractable disease. Patients should be carefully monitored for opportunistic infections during treatment.

A 21-Year-Old Woman with Joint Pain and Skin Ulceration

The illness started with pain and stiffness in her bilateral hands and wrists four months prior, with progression to bilateral elbows, knees, and ankles. The pain and stiffness were worse in the morning and limited her ability to use her hands or walk comfortably. She also noted swelling of her hands, knees, and ankles. The pain and swelling improved slightly with ibuprofen. She also noted increased fatigue, alopecia, decreased appetite, and nausea. She went to urgent care one month earlier and a physician prescribed ibuprofen and obtained initial serologies.

CD4+CXCR4+ T cells as a novel prognostic biomarker in patients with idiopathic inflammatory myopathy-associated interstitial lung disease

BACKGROUD

There is an unmet need for the development of new biomarkers for idiopathic inflammatory myopathy-associated interstitial lung disease (IIM-ILD).

METHODS

Peripheral CD4+CXCR4+ T cells, stromal cell-derived factor-1 and Krebs von den Lungen-6 were measured in patients with IIM-ILD (n = 85) and controls. The relation to pulmonary functions, high-resolution CT scores, specific clinical phenotypes and survival was analysed. Cytokine-expression profiling of these CD4+CXCR4+ T cells and their co-culture with pulmonary fibroblasts were conducted.

RESULTS

The peripheral percentages of CD4+CXCR4+ T cells were significantly elevated in IIM-ILD patients, and correlated with high-resolution CT score (r = 0.7136, P < 0.0001) and pulmonary function impairments, such as percentage of forced volume vital capacity (r = -0.4734, P = 0.0005). They were associated with anti-melanoma differentiation-associated gene 5 autoantibodies and the amyopathic DM phenotype. In IIM-ILD, peripheral percentages of CD4+CXCR4+ T cells ⩾30% revealed a 6-month mortality as high as 47%. These CD4+CXCR4+ T cells express high levels of IL-21 and IL-6. In vitro blockade of IL-21 signalling by neutralization of IL-21 or Janus kinase inhibitor could abolished the fibroblast proliferation.

CONCLUSION

Overall, peripheral CD4+CXCR4+ T cells appear to be a potentially valuable novel biomarker associated with the severity and prognosis of IIM-ILD. They promote pulmonary fibroblast proliferation via IL-21, which may herald future targeted treatments for this severe disease.

Cutaneous manifestations of dermatomyositis characterized by myositis-specific autoantibodies

Dermatomyositis (DM) is an inflammatory myopathy with characteristic skin manifestations, the pathologies of which are considered autoimmune diseases. DM is a heterogeneous disorder with various phenotypes, including myositis, dermatitis, and interstitial lung disease (ILD). Recently identified myositis-specific autoantibodies have been associated with distinct clinical features. For example, anti-melanoma differentiation-associated protein 5 antibodies have a high specificity for clinically amyopathic DM presenting rapidly progressive ILD. Furthermore, anti-transcriptional intermediary factor 1γ antibodies found in patients with juvenile and adult DM are closely correlated with malignancies, especially in elderly patients. Finally, patients with anti-aminoacyl-transfer RNA synthetase antibodies share characteristic clinical symptoms, including myositis, ILD, arthritis/arthralgia, Raynaud’s phenomenon, and fever; thus, the term “anti-synthetase syndrome” is also used. With a focus on the characteristic cutaneous manifestations in each subgroup classified according to myositis-specific autoantibodies, we introduce the findings of previous reports, including our recent analysis indicating that skin eruptions can be histopathologically classified into myositis-specific autoantibody-associated subgroups and used to determine the systemic pathologies of the different types of antibody-associated DM.

Meta-Analysis of Polymyositis and Dermatomyositis Microarray Data Reveals Novel Genetic Biomarkers

Polymyositis (PM) and dermatomyositis (DM) are both classified as idiopathic inflammatory myopathies. They share a few common characteristics such as inflammation and muscle weakness. Previous studies have indicated that these diseases present aspects of an auto-immune disorder; however, their exact pathogenesis is still unclear. In this study, three gene expression datasets (PM: 7, DM: 50, Control: 13) available in public databases were used to conduct meta-analysis. We then conducted expression quantitative trait loci analysis to detect the variant sites that may contribute to the pathogenesis of PM and DM. Six-hundred differentially expressed genes were identified in the meta-analysis (false discovery rate (FDR) < 0.01), among which 317 genes were up-regulated and 283 were down-regulated in the disease group compared with those in the healthy control group. The up-regulated genes were significantly enriched in interferon-signaling pathways in protein secretion, and/or in unfolded-protein response. We detected 10 single nucleotide polymorphisms (SNPs) which could potentially play key roles in driving the PM and DM. Along with previously reported genes, we identified 4 novel genes and 10 SNP-variant regions which could be used as candidates for potential drug targets or biomarkers for PM and DM.

The Brazilian Society of Rheumatology recommendations on investigation and diagnosis of systemic autoimmune myopathies

BACKGROUND

This research is recommended by the Myopathy Committee of the Brazilian Society of Rheumatology for the investigation and diagnosis of systemic autoimmune myopathies. BODY: A systematic literature review was performed in the Embase, Medline (PubMed) and Cochrane databases, including studies published until October 2018. PRISMA was used for the review, and the articles were evaluated, based on the Oxford levels of evidence. Ten recommendations were developed addressing different aspects of systemic autoimmune myopathy investigation and diagnosis.

CONCLUSIONS

The European League Against Rheumatism/ American College of Rheumatology (EULAR/ACR) classification stands out for the diagnosis of systemic autoimmune myopathies. Muscular biopsy is essential, aided by muscular magnetic resonance images and electroneuromyography in complementary research. Analysis of the factors related to prognosis with the evaluation of extramuscular manifestations, and comorbidities and intense investigation regarding differential diagnoses are mandatory.

Dermatomyositis: Diagnosis and treatment

The second article in this continuing medical education series reviews the initial evaluation of patients with suspected dermatomyositis (DM), the relevant work-up for malignancy and interstitial lung disease once a diagnosis of DM is made, and treatment recommendations for patients with DM based on disease severity, the presence of systemic symptoms, and myositis-specific antibody (MSA) profiles. This review emphasizes the emerging role of MSAs in the diagnosis of DM and highlights how MSAs can be used to guide the appropriate work-up for malignancy and interstitial lung disease. The treatment approach proposed by this continuing medical education series discusses both established and novel therapies for DM and highlights the importance of considering lesion type, degree of muscle involvement, presence of systemic symptoms, presence of MSAs, and patient age when determining the best treatment approach for a patient with DM.

Clinical significance of myositis-specific autoantibody profiles in Japanese patients with polymyositis/dermatomyositis

Myositis-specific autoantibodies, such as anti-melanoma differentiation associated gene 5 (MDA5) and anti-anti-amino acyl-tRNA synthetases (ARS) antibodies, are associated with interstitial lung diseases (ILD), which determine the prognosis of polymyositis/dermatomyositis (PM/DM) patients. However, there is a paucity of data on the clinical correlation between anti-Sjögren syndrome-related antigen A (anti-SSA)/Ro52 antibodies in PM/DM. We investigated the prevalence of myositis-specific autoantibodies including anti-SSA/Ro52 antibody and assessed the clinical significance of these antibodies in patients with PM/DM.We retrospectively reviewed demographic data and clinical outcomes in patients with PM/DM. The study population comprised 24 patients with PM and 60 patients with DM. The presence of anti-myositis-specific antibodies (MDA5, ARS, Jo-1, SSA/Ro52) was determined by immunosorbent assay (ELISA).Anti-MDA5 antibody was detected in 18 patients with DM (n = 60). Anti-ARS/anti-SSA/Ro52 antibodies were detected in 31 and 39 patients with PM/DM (n = 84). Rapidly progressive ILD patients were mainly found in the anti-MDA5 antibody-positive DM group. During the follow-up period, 9 patients died. Kaplan-Meier analysis demonstrated that survival rates seem to be lower in DM patients with anti-MDA5 antibodies compared with those without anti-MDA5 antibodies. Furthermore, dual positivity for anti-SSA/Ro52 and anti-MDA5 antibodies was significantly higher in nonsurviving DM patients compared with survivors.Although the presence of anti-ARS or anti-MDA5 antibodies is a prognostic marker in patients with PM/DM, combined presence of anti-SSA/Ro52 and anti-MDA5 antibodies represent another marker for clinical outcome in DM patients. Our results suggest that anti-SSA/Ro52 antibody positivity in DM patients with anti-MDA5 antibody reveals a subgroup of DM patients with poor prognosis.

Frequency, mutual exclusivity and clinical associations of myositis autoantibodies in a combined European cohort of idiopathic inflammatory myopathy patients

Objectives

To determine prevalence and co-existence of myositis specific autoantibodies (MSAs) and myositis associated autoantibodies (MAAs) and associated clinical characteristics in a large cohort of idiopathic inflammatory myopathy (IIM) patients.

Methods

Adult patients with confirmed IIM recruited to the EuroMyositis registry (n = 1637) from four centres were investigated for the presence of MSAs/MAAs by radiolabelled-immunoprecipitation, with confirmation of anti-MDA5 and anti-NXP2 by ELISA. Clinical associations for each autoantibody were calculated for 1483 patients with a single or no known autoantibody by global linear regression modelling.

Results

MSAs/MAAs were found in 61.5% of patients, with 84.7% of autoantibody positive patients having a sole specificity, and only three cases (0.2%) having more than one MSA. The most frequently detected autoantibody was anti-Jo-1 (18.7%), with a further 21 specificities each found in 0.2–7.9% of patients. Autoantibodies to Mi-2, SAE, TIF1, NXP2, MDA5, PMScl and the non-Jo-1 tRNA-synthetases were strongly associated (p < 0.001) with cutaneous involvement. Anti-TIF1 and anti-Mi-2 positive patients had an increased risk of malignancy (OR 4.67 and 2.50 respectively), and anti-SRP patients had a greater likelihood of cardiac involvement (OR 4.15). Interstitial lung disease was strongly associated with the anti-tRNA synthetases, anti-MDA5, and anti-U1RNP/Sm. Overlap disease was strongly associated with anti-PMScl, anti-Ku, anti-U1RNP/Sm and anti-Ro60. Absence of MSA/MAA was negatively associated with extra-muscular manifestations.

Conclusions

Myositis autoantibodies are present in the majority of patients with IIM and identify distinct clinical subsets. Furthermore, MSAs are nearly always mutually exclusive endorsing their credentials as valuable disease biomarkers.

•

Myositis specific autoantibodies very rarely coexist in the one individual allowing endotypes to be more precisely defined.

•

The association of anti-TIF1 and cancer-associated myositis is confirmed with a cut-off age of over 58 years.

•

In a large combined European myositis cohort associations of anti-SRP with carditis and anti-Mi-2 with cancer have emerged.

•

Myositis associated autoantibodies are strongly associated with having myositis in association with another connective tissue disease.

Biomarkers in Adult Dermatomyositis: Tools to Help the Diagnosis and Predict the Clinical Outcome

Dermatomyositis pathophysiology is complex. In recent years, medical research has identified molecules associated with disease activity. Besides providing insights into the driving mechanisms of dermatomyositis, these findings could provide potential biomarkers. Activity markers can be used to monitor disease activity in clinical trials and may also be useful in daily practice. This article reviews molecules that could be used as biomarkers for diagnosis and monitoring dermatomyositis disease activity.

Histological Findings of Organizing Pneumonia, Based on Transbronchial Lung Biopsy, May Predict Poor Outcome in Polymyositis and Dermatomyositis: Report of Two Autopsied Cases

Interstitial lung disease in polymyositis and dermatomyositis is a serious complication, associated with poor prognosis. In this article, we describe two cases with histological findings of organizing pneumonia, based on transbronchial lung biopsy. One is a 66-year-old female patient with clinically amyopathic dermatomyositis with anti-melanoma differentiation-associated gene 5 antibody, and another is a 61-year-old female patient with polymyositis with anti-Jo-1 antibody. Both of our cases rapidly deteriorated to death, and autopsy findings showed diffuse alveolar damage. Our experience indicates that transbronchial biopsy findings of organizing pneumonia may be a poor prognostic factor in clinically amyopathic dermatomyositis and polymyositis, in spite of the profile of myositis-specific antibodies.

Myositis-specific autoantibodies in dermatomyositis/polymyositis with interstitial lung disease

AIM

The prevalence and diagnostic values of myositis-specific autoantibodies (MSAs) and myositis-associated autoantibodies (MAAs) in dermatomyositis/polymyositis (DM/PM) were studied.

METHOD

A commercial immunoblot assay with 16 autoantigens was used to detect MSAs and MAAs in serum samples from 130 DM/PM patients, 100 disease controls, and 50 healthy subjects.

RESULTS

The prevalence of anti-Jo-1, anti-MDA5, anti-TIF1γ, anti-Mi-2α, and anti-Mi-2β was significantly higher in DM/PM than in other connective-tissue diseases (CTDs). Moreover, anti-MDA5 and anti-Ro-52 were significantly higher in DM/PM with interstitial lung disease (ILD) than in DM/PM without ILD, while that of anti-TIF1γ and anti-NXP2 were significantly lower in DM/PM with ILD than in DM/PM without ILD. For distinguishing DM/PM from other CTDs, the sensitivity, specificity, and positive predictive value (PPV) for anti-MDA5 were 28.46, 99.00, and 97.37%, respectively, with a positive likelihood ratio (LR+) of 28.46; they were 46.15, 58.00, and 58.82%, respectively, for anti-Ro-52 with an LR+ of 1.10. For distinguishing DM/PM with ILD from DM/PM without ILD, the sensitivity, specificity, and PPV for anti-MDA5 were 45.57, 100.00, and 100.00%, respectively, and for anti-Ro-52 were 60.76, 73.91, and 80.00%, respectively.

CONCLUSION

MSAs and MAAs serve as biomarkers for differentiating DM/PM from other CTDs as well as distinguishing DM/PM with ILD from DM/PM without ILD.

Systematic review and meta-analysis of prognostic factors for idiopathic inflammatory myopathy-associated interstitial lung disease

OBJECTIVE

To clarify prognostic factors for idiopathic inflammatory myopathy (IIM)-associated interstitial lung disease (ILD).

DESIGN

Systematic review and meta-analysis using the Grades of Recommendation, Assessment, Development and Evaluation system.

DATA SOURCES

Medline, EMBASE and Science Citation Index Expanded were searched through 9 August 2018.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

The review includes primary studies addressing all-cause mortality of IIM-associated ILD. Potential prognostic factors were any clinical information related to the outcome.

DATA EXTRACTION AND SYNTHESIS

Two reviewers extracted relevant data independently and assessed risk of bias using the Quality in Prognostic Studies tool. Meta-analysis was conducted using a random effects model and if inappropriate the results were reported qualitatively. Prognostic factors were determined based on statistically significant results derived from multivariate analysis.

RESULTS

Of a total of 5892 articles returned, 32 were deemed eligible for analysis and cumulatively, these studies reported 28 potential prognostic factors for all-cause mortality. Each study was subject to certain methodological constraints. The four prognostic factors, which demonstrated statistically significant results on both univariate and multivariate analyses, were as follows: age (MD 5.90, 3.17-8.63/HR 1.06, 1.02-1.10 and 2.31, 1.06-5.06), acute/subacute interstitial pneumonia (A/SIP) (OR 4.85, 2.81-8.37/HR 4.23, 1.69-12.09 and 5.17, 1.94-13.49), percentage of predicted forced vital capacity (%FVC) (OR 0.96, 0.95-0.98/HR 0.96, 0.93-0.99) and anti-Jo-1 antibody (OR 0.35, 0.18-0.71/HR 0.004, 0.00003-0.54) (univariate/multivariate, 95% CI). Other prognostic factors included ground glass opacity/attenuation (GGO/GGA) and extent of radiological abnormality. The quality of the presented evidence was rated as either low or very low.

CONCLUSIONS

Older age, A/SIP, lower value of %FVC, GGO/GGA and extent of radiological abnormality were demonstrated to predict poor prognosis for IIM-associated ILD while a positive test for anti-Jo-1 antibody indicated better prognosis. However, given the weak evidence they should be interpreted with caution.

TRIAL REGISTRATION NUMBER

CRD42016036999.

Anti-MDA5 Antibody Spectrum in Western World

PURPOSE OF REVIEW

Anti-melanoma differentiation-associated gene 5 (anti-MDA5) is a novel and highly specific myositis-associated autoantibody, which defines a unique phenotype among patients with dermatomyositis (DM).

RECENT FINDINGS

Anti-MDA5 was originally characterized in Japan in DM patients with hallmark cutaneous features and no proximal muscle weakness and termed clinically amyopathic DM (CADM). Anti-MDA5 has characteristic cutaneous manifestations which include tender palmar papules and cutaneous ulcerations, along with an increased frequency of interstitial lung disease (ILD) that can be rapidly progressive (RPILD) and fatal. This review will highlight the clinical significance of anti-MDA5 autoantibodies in Caucasian DM patients.

Clinically Amyopathic Dermatomyositis with Interstitial Pneumonia That Was Successfully Treated with Plasma Exchange

Patients with clinically amyopathic dermatomyositis (CADM), a subset of dermatomyositis characterized by a lack of muscle involvement, frequently develop rapidly progressive and treatment-resistant interstitial lung disease. We report the case of a 49-year-old man who was diagnosed with CADM. He developed interstitial pneumonia, which did not respond to combination therapy with methylprednisolone pulse therapy, cyclophosphamide, and cyclosporine. We therefore attempted plasma exchange. After 7 courses of therapeutic plasma exchange, the interstitial pneumonia gradually improved. This case suggests that plasma exchange might be an effective therapeutic option for patients with progressive interstitial lung disease in steroid- and immunosuppressive therapy-refractive CADM.

Recurrence of anti-MDA5 antibody-positive clinically amyopathic dermatomyositis after long-term remission: A case report

RATIONALE

Among all dermatomyositis (DM) patients, antimelanoma differentiation-associated gene 5 antibody (anti-MDA5 Ab) positive patients have significantly poor short-term mortality, whereas they experience less relapses over the long term after the remission. We report the case of a patient with anti-MDA5 Ab-positive clinically amyopathic dermatomyositis (CADM) with the recurrence of interstitial lung disease (ILD) after 7 years of remission. There has been no case report of an anti-MDA5 Ab-positive DM patient with the recurrence of ILD after 7 years of long-term remission.

PATIENT CONCERNS

A 70-year-old Japanese woman was diagnosed with anti-MDA5 Ab-positive CADM and ILD. After achieving 7 years long-term remission, she was admitted to our department with erythema on the fingers and interstitial pneumonia. Her anti-MDA5 Ab titer was elevated.

DIAGNOSES

We diagnosed recurrent CADM complicated with ILD.

INTERVENTIONS

We successfully treated her with 1,000 mg of methyl-prednisolone pulse and intravenous cyclophosphamide therapy followed by prednisolone 50 mg/day and an increase of cyclosporine.

OUTCOMES

After that treatment, the patient's skin symptoms and interstitial pneumonia were relieved. All laboratory investigations such as ferritin, the serum markers of interstitial pneumonia (i.e., SP-A, SP-D), and the titer of anti-MDA5 Ab showed signs of improvement.

LESSONS

Her case suggests that careful physical examinations and monitoring the serum markers are important even after long-term remission is achieved.

Rituximab for refractory rapidly progressive interstitial lung disease related to anti-MDA5 antibody-positive amyopathic dermatomyositis

To report our experience in using rituximab (RTX) for treating refractory rapidly progressive interstitial lung disease (RP-ILD) complicating anti-melanoma differentiation-associated gene 5 antibody (anti-MDA5 Ab)-positive amyopathic dermatomyositis (ADM). Medical records of four ADM patients with refractory RP-ILD treated with RTX therapy were reviewed retrospectively. All four patients were tested positive for anti-MDA5 Ab and failed to respond to high-dose systemic steroid and other intensive immunosuppressive therapies. Respiratory symptoms, lung function tests, and high-resolution computed tomography (HRCT) of the chest were compared before and after the first course of RTX. After RTX treatment, all four patients had improvement in the respiratory symptoms in terms of New York Heart Association classification. Two patients successfully had their supplementary oxygen therapy weaned off. The lung function tests were significantly better in all patients. The HRCT showed improvement in three patients while the other one remained static. The recalcitrant vasculitic rashes associated with the anti-MDA5 Ab were also better in all patients. The average daily prednisolone dose dropped from 20 to 6.25 mg post-treatment. None of the patients died throughout the follow-up period which ranged from 6 months to 2 years. However, two patients developed chest infection and one wound infection within 6 months after the RTX infusion. Our results suggest that RTX may be a useful therapy for anti-MDA5 Ab-positive ADM associated with RP-ILD. However, infection is the major risk.

Improved quantification of a commercial enzyme-linked immunosorbent assay kit for measuring anti-MDA5 antibody

OBJECTIVES

To compare the quantitative performance for measuring anti-MDA5 antibody titer of two enzyme-linked immunosorbent assay (ELISA) systems: an in-house ELISA and the commercial MESACUP^TM anti-MDA5 test.

METHODS

Anti-MDA5 antibody titer was measured in sera from 70 patients with dermatomyositis using an in-house ELISA and the MESACUP^TM anti-MDA5 test side-by-side. For the commercial ELISA kit, serum samples diluted 1:101 were used according to the manufacturer's protocol, but serial dilutions of sera were also examined to identify the optimal serum dilution for quantification.

RESULTS

The anti-MDA5 antibody titers measured by the in-house and commercial ELISAs were positively correlated with each other (r = 0.53, p = .0001), but the antibody titer measured by the commercial ELISA was less sensitive to change after medical treatment, and 37 (80%) of 46 anti-MDA5-positive sera had antibody titer exceeding the quantification range specified by the manufacturer (≥150 index). Experiments using diluted serum samples revealed that diluting the sera 1:5050 improved the quantitative performance of the MESACUP^TM anti-MDA5 test, including a better correlation with the in-house ELISA results and an increased sensitivity to change.

CONCLUSION

We improved the ability of the commercial ELISA kit to quantify anti-MDA5 antibody titer by altering its protocol.

Advances in biomarkers for dermatomyositis

Dermatomyositis (DM) and polymyositis (PM) are heterogeneous complex autoimmune diseases involving muscle damage. Patients with DM and PM display a wide spectrum of clinical manifestations and serological biomarkers, which may mislead and delay the proper diagnosis. Therefore, specific biomarkers or indicators for diagnosing DM and PM and monitoring disease activity are essential. Significant progress has been made through identifying novel serological biomarkers for DM and PM in recent years. Our aim is to focus on novel biomarkers for diagnosing and monitoring disease activity in DM and PM to highlight their predictive value and applicability in clinical practice.

Autoantibodies Associated With Connective Tissue Diseases: What Meaning for Clinicians?

Connective tissue diseases (CTDs) such as systemic lupus erythematosus, systemic sclerosis, myositis, Sjögren's syndrome, and rheumatoid arthritis are systemic diseases which are often associated with a challenge in diagnosis. Autoantibodies (AAbs) can be detected in these diseases and help clinicians in their diagnosis. Actually, pathophysiology of these diseases is associated with the presence of antinuclear antibodies. In the last decades, many new antibodies were discovered, but their implication in pathogenesis of CTDs remains unclear. Furthermore, the classification of these AAbs is nowadays misused, as their targets can be localized outside of the nuclear compartment. Interestingly, in most cases, each antibody is associated with a specific phenotype in CTDs and therefore help in better defining either the disease subtypes or diseases activity and outcome. Because of recent progresses in their detection and in the comprehension of their pathogenesis implication in CTD-associated antibodies, clinicians should pay attention to the presence of these different AAbs to improve patient's management. In this review, we propose to focus on the different phenotypes and features associated with each autoantibody used in clinical practice in those CTDs.