Clinically amyopathic dermatomyositis

Clinically amyopathic dermatomyositis: Clinical, laboratory, and histopathological features

BACKGROUND

Despite the advancements in the categorization of clinically amyopathic dermatomyositis (CADM), the classification and diagnosis of its subtypes are still challenging. The aim of our study was to describe the clinicopathological features of CADM and assess the differences between amyopathic dermatomyositis (ADM) and hypomyopathic dermatomyositis (HDM).

METHODS

This retrospective study included 43 patients with CADM diagnosed at our institution from 2016 to 2020. Patients were subclassed into ADM (n = 30) and HDM (n = 13) groups to assess their clinicopathological differences.

RESULTS

All included patients had characteristic cutaneous manifestations of dermatomyositis; 67.4% had myositis-associated auto-antibodies, including ANA (32.6%), RNP (14.0%), anti-Ro52 (9.3%), anti-p155/140 (7.0%), rheumatoid factor (7.0%), anti-NXP-2 (4.7%), anti-MDA5 (2.3%), and anti-Jo-1 (2.3%) antibodies. One patient had associated interstitial lung disease, and another patient had oral squamous cell carcinoma. The histopathological findings included mucin deposition (69.8%), telangiectasia (65.1%), lymphocytic infiltrate (48.8%), vacuolar interface dermatitis (46.5%), and epidermal atrophy (14.0%). Compared to patients with HDM, ADM patients were significantly less likely to have epidermal atrophy, 3.3% versus 38.5% (p = 0.006), and more likely to have mucin deposition, 80.0% versus 46.2% (p = 0.028).

CONCLUSION

We described the clinicopathological features of CADM and highlighted the distinctions between ADM and HDM dermatopathologic findings. This information may prove helpful in diagnosing ambiguous lesions.

Clinical application of blood purification in polymyositis/dermatomyositis

INTRODUCTION

We investigated the clinical efficacy and safety of blood purification technology in patients with polymyositis/dermatomyositis.

METHODS

In a study of 22 patients, 10 cases received blood purification treatment (5 cases received plasma exchange, 5 cases received plasma HA280 immunoadsorption), and 12 cases served as the control group. A 3-month follow-up was conducted to compare the clinical manifestations and laboratory examination.

RESULTS

Symptoms and signs of patients in treatment group were significantly improved, and the hormone usage was lower than the control group. For patients with normal creatine kinase level and ferritin level below three times the upper limit of normal, there was a positive correlation between their N/L values and MDAAT scores.

CONCLUSION

The results of this study suggest that blood purification therapy, including plasma HA280 immunoadsorption and plasma exchange, is an effective and safe treatment for patients with polymyositis/dermatomyositis, offering assistance in reducing hormone usage in the long-term.

Antibodies against Small Ubiquitin-like Modifier Activating Enzyme May Be a Protective Factor from Rapid Progressive Interstitial Lung Disease in Patients Bearing Antibodies against Melanoma Differentiation Associated Gene 5

Background: Anti-MDA5 antibody-bearing (anti-MDA5+)-dermatomyositis (DM) or polymyositis (PM) is notorious for causing rapidly progressive interstitial lung disease (RPILD) and/or cancers with high mortality rate. However, anti-MDA5 antibodies (Abs) are also found in other connective tissue diseases and their link with RPILD, especially with regard to the mortality rate, are unknown. Methods: We retrospectively recruited 71 patients bearing anti-MDA5-Abs in serum, stratified them in terms of a presence or absence of RPILD, and evaluated their clinical features, laboratory findings, associated myositis antibodies, concurrent connective tissue disease (CTD) as well as newly developed malignancies. Results: In total, 39 (55%) patients presented with DM/PM, but 32 (45%) did not. In total, 22 of the former and 11 of the latter developed RPILD eventually, accounting for a total of 46% of all MDA-5 bearing patients. On the other hand, 15 of all 71 (21.1%) patients had cancers. Among the 32 patients who did not have DM/PM, 27 (38.0% of all 71) had other CTDs, indicating that only 5 (7.0% of 71) patients did not have CTDs. Senility (odds ratio (OR) = 1.816, p = 0.032), presence of anti-Ro-52 antibody (OR = 1.676, p = 0.018), elevated C-reactive protein (CRP, OR = 4.354, p < 0.001) and carcinoembryonic antigen (CEA, OR = 2.625, p = 0.005) posed risks for RPILD. High lactose dehydrogenase (LDH, p = 0.009), CRP (p = 0.001) and CEA (p = 0.001), ferritin (p ≤ 0.001) and low albumin (p ≤ 0.001) were significantly associated with mortality. Anti-SAE antibodies were negatively correlated with RPILD as analyzed by univariate (OR = 0.245, p = 0.017) and multivariate (OR = 0.058, p = 0.036) regressions, indicating that they may be a protective factor in relation to RPILD (OR = 0.543, p = 0.008) or fatality (OR = 0.707, p = 0.012), which was also demonstrated in subgroup analyses. Conclusions: In contrast to various risk factors for RPILD or mortality, anti-SAE antibodies might conversely be a protective factor in anti-MDA5+ patients.

Comparison of characteristics and anti-MDA5 antibody distribution and effect between clinically amyopathic dermatomyositis and classic dermatomyositis: a retrospective case-control study

Background

Clinically amyopathic dermatomyositis (CADM) is a distinct subtype of dermatomyositis (DM) characterized by typical DM cutaneous findings but with minimal or no evidence of myositis. It possesses unique features different from classic DM (CDM). Anti-melanoma differentiation-associated gene 5 (MDA5) antibodies were found in CADM and are thought to increase the risk of rapidly progressive interstitial lung disease (RP-ILD) and are present in both CADM and CDM patients, affecting their condition and prognosis. Nevertheless, no large-sample studies have compared all aspects concerning patients with CADM and those with CDM. This study aimed to investigate differences in clinical characteristics and risk factors for mortality between CADM and CDM and to clarify the distribution and impact of anti-MDA5 antibodies in patients with these conditions.

Methods

A retrospective case-control study included 330 patients and collected and analyzed their clinical data from The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Hospital of Traditional Chinese Medicine between January 2015 and July 2022; all patients were followed up to evaluate changes in their condition and prognosis. Several new cohorts were designed around anti-MDA5 antibodies to explore their distribution and impact in CADM and CDM.

Results

We found CADM to be associated with higher rates of mortality, 1-year mortality, interstitial lung disease (ILD), and RP-ILD than CDM. In CADM, RP-ILD, anti-MDA5 antibodies, and high ferritin and lactate dehydrogenase (LDH) levels were identified as independent risk factors for death. In CDM, the neutrophil-to-lymphocyte ratio, anti-MDA5 antibodies, and high ferritin levels were shown to be independent risk factors for death, whereas mechanic's hand was considered a protective factor against it. Anti-MDA5 antibody-positive patients did not exhibit any significant difference based on whether they belonged to the CADM or CDM groups. When no anti-MDA5 antibody-positive patients participated, the ferritin levels and rates of RP-ILD and ILD were still higher in CADM than in CDM; however, such differences decreased, whereas the LDH levels, rates of mortality, and 1-year mortality did not differ. Anti-MDA5 antibody-positive patients consistently showed higher LDH and ferritin levels, lower lymphocyte levels, higher probability of RP-ILD and ILD, and worse prognosis than anti-MDA5 antibody-negative patients, irrespective of whether the patients had DM, CADM, or CDM.

Conclusion

Patients with CADM exhibit relatively worse symptoms, serological findings, and prognosis than those with CDM. Furthermore, patients with CADM and those with CDM have commonalities and differences in risk factors for death. Moreover, CADM may necessitate earlier and more aggressive treatment strategies than CDM. Anti-MDA5 antibodies occur at a high level in patients with CADM, not only affecting the symptoms and prognosis of DM but also having a non-negligible impact on the differences between CADM and CDM. Hence, screening for anti-MDA5 antibodies in patients with CADM and CDM is extremely essential.

Identification of Three Different Phenotypes in Anti-Melanoma Differentiation-Associated Gene 5 Antibody-Positive Dermatomyositis Patients: Implications for Prediction of Rapidly Progressive Interstitial Lung Disease

OBJECTIVE

There is substantial heterogeneity among the phenotypes of patients with anti-melanoma differentiation-associated gene 5 antibody-positive (anti-MDA5+) dermatomyositis (DM), hindering disease assessment and management. This study aimed to identify distinct phenotype groups in patients with anti-MDA5+ DM and to determine the utility of these phenotypes in predicting patient outcomes.

METHODS

A total of 265 patients with anti-MDA5+ DM were retrospectively enrolled in the study. An unsupervised hierarchical cluster analysis was performed to characterize the different phenotypes.

RESULTS

Patients were stratified into 3 clusters characterized by markedly different features and outcomes. Cluster 1 (n = 108 patients) was characterized by mild risk of rapidly progressive interstitial lung disease (RPILD), with the cumulative incidence of non-RPILD being 85.2%. Cluster 2 (n = 72 patients) was characterized by moderate risk of RPILD, with the cumulative incidence of non-RPILPD being 73.6%. Patients in cluster 3 (n = 85 patients), which was characterized by a high risk of RPILD and a cumulative non-RPILD incidence of 32.9%, were more likely than patients in the other 2 subgroups to have anti-Ro 52 antibodies in conjunction with high titers of anti-MDA5 antibodies. All-cause mortality rates of 60%, 9.7%, and 3.7% were determined for clusters 3, 2, and 1, respectively (P < 0.0001). Decision tree analysis led to the development of a simple algorithm for anti-MDA5+ DM patient classification that included the following 8 variables: age >50 years, disease course of <3 months, myasthenia (proximal muscle weakness), arthritis, C-reactive protein level, creatine kinase level, anti-Ro 52 antibody titer, and anti-MDA5 antibody titer. This algorithm placed patients in the appropriate cluster with 78.5% accuracy in the development cohort and 70.0% accuracy in the external validation cohort.

CONCLUSION

Cluster analysis identified 3 distinct clinical patterns and outcomes in our large cohort of anti-MDA5+ DM patients. Classification of DM patients into phenotype subgroups with prognostic values may help physicians improve the efficacy of clinical decision-making.

A case of clinically amyopathic dermatomyositis in a Filipino woman

This is a case of a 59-year-old woman who presented with a 2-year history of heliotrope rash, Gottron's papules, shawl sign, V-neck sign, and muscle weakness. She was previously managed as a case of systemic lupus erythematosus and initially responded to unrecalled corticosteroids. She was admitted due to a 1-month progressively enlarging sacral mass, which eventually turned out to be an abscess. While the abscess was being treated, her autoimmune condition was worked up, and she was then managed as a case of clinically amyopathic dermatomyositis (CADM) with interstitial lung disease (ILD). She received corticosteroids and underwent the first cycle of cyclophosphamide infusion prior to discharge.

Anti-MDA5 Amyopathic Dermatomyositis-A Diagnostic and Therapeutic Challenge

Clinically amyopathic Dermatomyositis (CADM) is a rare subtype of idiopathic inflammatory myositis, associated with no muscular manifestations, which is more frequent in Asian women. Anti-melanoma differentiation-associated gene 5 (MDA5) antibodies are a recently discovered type of specific autoantibodies associated with myositis. The anti-MDA5 DM was initially described in Japan and later it was discovered that the target antigen was a protein implicated in the innate immune response against viruses, that is encoded by the melanoma differentiation-associated gene 5. Anti-MDA5 DM is characteristically associated with distinguished mucocutaneus and systemic manifestations, including skin ulcerations, palmar papules, arthritis, and interstitial-lung disease. Patients with anti-MDA5 positivity have a high risk of developing rapid progressive interstitial-lung disease (RP-ILD), with a poor outcome. As a result, despite high mortality, diagnosis is often delayed, necessitating increased awareness of this possible condition. Despite a severe course of lung disease and an increased mortality rate, there is currently no standard treatment. Recent insights based on observational studies and case reports support combined therapy with immunosuppressive drugs and corticotherapy, as soon as the symptoms appear. The aim of this paper is to describe anti-MDA5 DM, focusing on the recent literature about the unique clinical manifestations and therapeutic options, starting from a severe clinical case diagnosed in our Rheumatology Department.

Anti-MDA5 Antibody-positive Dermatomyositis with Rapidly Progressive Interstitial Pneumonia Presenting with Nephrotic Syndrome during Treatment with Corticosteroids and Cyclosporine

A 50-year-old Japanese woman with anti-melanoma differentiation-associated gene 5 antibody (anti-MDA5 antibody)-positive dermatomyositis presenting with rapidly progressive interstitial pneumonia was treated with corticosteroids and cyclosporine. She developed nephrotic syndrome during the treatment regimen with corticosteroids and cyclosporine. A kidney biopsy revealed a thrombotic microangiopathy (TMA) glomerular lesion. Anti-MDA5 antibody-positive dermatomyositis is prone to severe interstitial lung disease (ILD) and is often exacerbated and refractory to treatment. Renal symptoms might be due to TMA of the kidney, and this may be a sign that more intensive treatment is needed. Patients sometimes develop acute kidney injury, which may be due to the TMA.

COVID-19 Disease and Dermatomyositis: A Mini-Review

The pandemic of coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 has caused a large number of deaths, and there is still no effective treatment. COVID-19 can induce a systemic inflammatory response, and its clinical manifestations are diverse. Recently, it has been reported that COVID-19 patients may develop myositis and interstitial pulmonary disease similar to dermatomyositis (DM). This condition is similar to the rapidly progressive interstitial lung disease associated with MDA5+ DM that has a poor prognosis and high mortality, and this poses a challenge for an early identification. Suppression of the immune system can protect COVID-19 patients by preventing the production of inflammatory cytokines. This article attempts to explore the possibility of a relationship between COVID-19 and DM in terms of the potential pathogenesis and clinical features and to analyze the therapeutic effect of the immunosuppressive drugs that are commonly used for the treatment of both DM and COVID-19.

Clinically amyopathic dermatomyositis with interstitial lung disease double-positive for anti-MDA5 and anti-PL12 antibodies

Anti-melanoma differentiation-associated gene 5 (MDA5) and anti-aminoacyl-tRNA synthetase (ARS) antibodies are two major myositis-specific autoantibodies with distinct clinical features. However, the clinical course remains unclear in patients with clinically amyopathic dermatomyositis (CADM)-interstitial lung disease (ILD) who have co-existing anti-MDA5 and anti-ARS antibodies. Here, we describe the case of a 32-year-old woman with CADM-ILD who had anti-MDA5 and anti-PL12 antibodies. Her serum ferritin level was within the normal range. However, chest computed tomography revealed bilateral lower-lobe consolidation and ground-glass opacities. Treatment with prednisolone and immunosuppressants was successful in improving the skin lesion and ILD, but relapse occurred on reducing the dose of prednisolone. These clinical features match those of anti-ARS antibody-positive dermatomyositis-ILD. Because these two conditions show significantly different clinical features and require different intensities of treatment, clinicians should carefully follow-up these patients throughout the course of the disease.

Elevated carcinoembryonic antigen predicts rapidly progressive interstitial lung disease in clinically amyopathic dermatomyositis

OBJECTIVES

The present study aimed to determine the correlation between serum carcinoembryonic antigen (CEA) level and the severity of interstitial lung disease (ILD) in clinically amyopathic DM (CADM) patients.

METHODS

We performed a retrospective study including 41 Chinese CADM patients without malignancy. Serum CEA levels, clinical and laboratory findings were collected. Association tests between CEA levels and disease activity parameters were performed.

RESULTS

Among the 41 patients, 16 (39.0%) developed rapidly progressive (RP)-ILD; of them, 14 (87.5%) had elevated serum CEA levels. Multivariate logistic regression analysis indicated that an elevated serum CEA level was an independent risk factor for RP-ILD. The incidence of elevated CEA level was significantly higher in patients with RP-ILD than in those without RP-ILD (87.5 vs 16.0%, P < 0.001). Furthermore, CEA levels were higher in patients with CADM with RP-ILD [26.87 (6.71) μg/l] than in those without RP-ILD [3.23 (0.64) μg/l] (P < 0.001). CEA levels in CADM patients were associated with the ferritin, alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase levels, and CT scores of the lungs. Also, elevated CEA levels are related to the organizing pneumonia pattern and lower lung zone consolidation in high-resolution CT. Moreover, the cumulative survival rate was significantly lower (68.4 vs 31.6%, P < 0.001) in the group with a CEA level >8.75 μg/l than that in the group with a CEA level <8.75 μg/l.

CONCLUSIONS

An elevated serum CEA level is common in patients with CADM, and a higher serum CEA level is a powerful indicator of RP-ILD and poor prognosis in those patients.

The aetiopathogenic significance, clinical relevance and therapeutic implications of vasculopathy in idiopathic inflammatory myopathy

It is 120 years since 'angiomyositis' was included alongside 'polymyositis' and 'dermatomyositis' in an attempt to propose a taxonomy that reflected the major clinical characteristics of idiopathic inflammatory myopathy (IIM). Endothelial injury, perivascular inflammation and capillary loss are important histological findings in affected tissues in IIM. Overt vascular clinical features including RP and abnormal nailfold capillaroscopy (NC) are also common in IIM. Despite the presence of endothelial injury, perivascular inflammation and capillary loss in affected tissues in IIM, and the presence of clinical features such as RP and NC abnormalities, the pathogenic and therapeutic implications of vasculopathy in IIM have been somewhat overlooked. RP and NC abnormalities are not always present, providing a valuable opportunity to explore aetiopathogenic factors driving vasculopathy within autoimmune rheumatic disease. The present review examines the aetiopathogenic, prognostic and therapeutic significance of vasculopathy in IIM. We describe the prevalence and clinical relevance of vasculopathy in IIM, and consider how vasculopathy may be better utilized to support improved IIM diagnosis and disease classification. Areas of unmet research need are highlighted where relevant.

Prevalence of interstitial lung disease in polymyositis and dermatomyositis: A meta-analysis from 2000 to 2020

OBJECTIVE

Interstitial lung disease (ILD) is the most important prognostic factor for mortality in patients with polymyositis (PM) and dermatomyositis (DM), but the prevalence of ILD in PM/DM may vary between countries. The aim of this study was to determine the overall prevalence of ILD in global patients with PM/DM.

METHODS

We performed a systematic literature review of studies published from Jan 1, 2000 to April 30, 2020 on ILD and PM/DM. We extracted data and pooled the prevalence by using a random-effect model due to high heterogeneity. Heterogeneity was assessed by subgroup analysis and sensitivity analysis.

RESULTS

A total of 34 studies with 10,130 patients were included in our meta-analysis. Pooled data demonstrated that the global prevalence of ILD in patients with PM/DM was 0.41 (95% confidence interval [CI] 0.35-0.48). However, this prevalence varied with geographical locations and time trends. The prevalence of ILD in PM/DM was 0.5 (95% CI 0.42-0.57) in Asia, 0.23 (95% CI 0.15-0.31) in America, and 0.26 (95% CI 0.18-0.34) in Europe. A higher prevalence of ILD was reported in studies published in 2011-2015 (0.43, 95% CI 0.34-0.52) and 2016-2020 (0.45, 95% CI 0.35-0.54), compared with those published in 2000-2010 (0.27, 95% CI 0.16-0.39). The pooled prevalence of ILD in patients with DM, PM, and clinically amyopathic dermatomyositis subtype was 0.42 (95% CI 0.35-0.49), 0.35 (95% CI 0.27-0.42), and 0.53 (95% CI 0.32-0.74), respectively. Patients with anti-Jo-1 and anti-melanoma differentiation-associated gene 5 antibodies were more likely to develop ILD than other myositis-specific autoantibodies.

CONCLUSION

The global prevalence of ILD in patients with PM/DM was approximately 41% and the condition was predominant in Asians. This highlights potential genetic and environmental differences in the pathogenesis of ILD in patients with PM/DM. More studies are required to elucidate the specific associations.

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.

Mortality Risk Prediction in Amyopathic Dermatomyositis Associated With Interstitial Lung Disease: The FLAIR Model

BACKGROUND

The prognosis of amyopathic dermatomyositis (ADM)-associated interstitial lung disease (ILD) is poor. A mortality risk score model is needed to predict survival in patients with ADM-ILD and to guide clinical treatment.

RESEARCH QUESTION

How to identify patients with ADM-ILD who are at high risk and to predict patient outcome based on a risk stratification model?

STUDY DESIGN AND METHODS

We evaluated 207 patients with ADM-ILD in this prospective inception study. We used a multivariable Cox proportional hazards model to identify the independent prognostic risk factors and created a risk score model according to patient data from January 2012 to December 2016. We used the index of prediction accuracy that uses the Brier score to reflect both discrimination and calibration of the model. The model was validated in an independent group of patients from January 2017 to June 2018.

RESULTS

We developed a combined risk score, the FLAIR score, that included the following values and scores: ferritin (<636 ng/mL, 0; ≥636 ng/mL, 2), lactate dehydrogenase (<355 U/L, 0; ≥355 U/L, 2), antimelanoma differentiation-associated gene 5 antibody (negative, 0; +, 2; ++, 3; +++, 4), high-resolution CT imaging score (<133, 0; ≥133, 3), and rapidly progressive ILD (RPILD) (non-RPILD, 0; RPILD, 2). We divided patients into three risk groups according to the FLAIR score: low, 0 to 4; medium, 5 to 9; and high, 10 to 13. In both discovery and validation cohorts, high-risk patients had significantly higher mortality rates than low- and medium-risk patients (P < .001).

INTERPRETATION

The FLAIR risk score model could help to predict survival in patients with ADM-ILD and to guide further clinical research on risk-based 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.

Noninvasive positive pressure ventilator deteriorates the outcome of pneumomediastinum in anti-MDA5 antibody-positive clinically amyopathic dermatomyositis

BACKGROUND

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody (Ab)-positive clinically amyopathic dermatomyositis (CADM) with pneumomediastinum (PNM) is a life-threatening condition. We aim to determine the prognostic factors affecting survival of patients with anti-MDA5 Ab-positive CADM complicated with PNM.

METHODS

We retrospectively established a cohort of patients with anti-MDA5 Ab-positive CADM complicated with PNM from April 2013 to July 2019. Demographic data and clinical characteristics from medical records were analyzed and variables were compared between survivors and nonsurvivors. We performed univariate and multivariate survival analyses by Cox regression. Survival curves were depicted by the Kaplan-Meier method.

RESULTS

Among 133 patients with anti-MDA5 Ab-positive CADM, 20 were diagnosed with PNM. The cumulative estimated Kaplan-Meier survival rate was 85% at 1 week, 55% at 1 month, and 40% at 1 year. Univariate analysis indicated several factors associated with survival. Worse liver function (AST, p = 0.043; LDH, p = 0.002; TBIL, p = 0.038), higher CRP level (p = 0.044), higher HRCT score (p = 0.022), and using noninvasive positive pressure ventilation (NPPV) (p < 0.01) were associated with poor prognosis. In a multivariate Cox regression model, AST level and using NPPV were indicated to be independent predictors of poor prognosis.

CONCLUSION

In this research, we found that the incidence rate of PNM in anti-MDA5 Ab-positive CADM was 15.5%, obviously higher than in classical DM. The application of noninvasive positive pressure ventilator (NPPV) and higher AST level were independent risk factors for survival.Key Points• Anti-MDA5 Ab-positive CADM complicated with PNM is a life-threatening condition with an incidence rate of 15.5%.• The application of NPPV and worse liver function were independent risk factors for survival of anti-MDA5 Ab-positive CADM patients complicated with PNM.

Utilize lung ultrasound B-lines and KL-6 to monitor anti-MDA-5 antibody-positive clinically amyopathic dermatomyositis-associated interstitial lung disease: a case report and literature review

In the past decade, lung ultrasound (LUS) B-lines and serum Krebs von den Lungen-6 (KL-6) antigen have been recognized as biomarkers of the connective tissue disease-associated interstitial lung diseases (CTD-ILDs). Robust data have demonstrated that B-lines total numbers and KL-6 levels are correlated with high-resolution computed tomography findings, pulmonary function test, and some clinical parameters in CTD-ILDs. However, limited data are available regarding the use of these two biomarkers to follow CTD-ILDs. Herein, we report a case with anti-melanoma differentiation-associated gene 5 antibody-positive clinically amyopathic dermatomyositis-associated ILD, successfully treated with high-dose methylprednisolone, cyclophosphamide, intravenous immunoglobulin, pirfenidone, and followed using lung ultrasound and KL-6.

Anti-MDA5 antibody-positive hypomyopathic dermatomyositis complicated with pneumomediastinum

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive clinically amyopathic dermatomyositis (CADM) is frequently associated with rapidly progressive interstitial lung disease (RP-ILD) resulting in high mortality. Here we report a 51-year-old Japanese woman with anti-MDA5 antibody-positive hypomyopathic dermatomyositis (DM) who developed RP-ILD. She developed respiratory failure and pneumomediastinum, however her RP-ILD responded favorably to the combined immunosuppressive treatments consisting of steroids, intravenous cyclophosphamide and tacrolimus. She was complicated with severe infections, which were successfully managed by combined modality therapy including artificial ventilation and antibiotics in addition to immunosuppressive treatments in parallel to the decline of anti-MDA5 antibody titer (>150 Index to 75 Index). She was discharged after 6 months of treatment without any respiratory sequelae. Hypomyopathic DM patients with high titers of anti-MDA5 antibody should be treated with aggressive immunosuppressive therapies and closely monitored to prevent various infections.

Interstitial Lung Disease and Pulmonary Fibrosis: A Practical Approach for General Medicine Physicians with Focus on the Medical History

Interstitial lung disease (ILD) and pulmonary fibrosis comprise a wide array of inflammatory and fibrotic lung diseases which are often confusing to general medicine and pulmonary physicians alike. In addition to the myriad of clinical and radiologic nomenclature used in ILD, histopathologic descriptors may be particularly confusing, and are often extrapolated to radiologic imaging patterns which may further add to the confusion. We propose that rather than focusing on precise histologic findings, focus should be on identifying an accurate etiology of ILD through a comprehensive and detailed medical history. Histopathologic patterns from lung biopsy should not be dismissed, but are often nonspecific, and overall treatment strategy and prognosis are likely to be determined more by the specific etiology of ILD rather than any particular histologic pattern. In this review, we outline a practical approach to common ILDs, highlight important aspects in obtaining an exposure history, clarify terminology and nomenclature, and discuss six common subgroups of ILD likely to be encountered by general medicine physicians in the inpatient or outpatient setting: Smoking-related, hypersensitivity pneumonitis, connective tissue disease-related, occupation-related, medication-induced, and idiopathic pulmonary fibrosis. Accurate diagnosis of these forms of ILD does require supplementing the medical history with results of the physical examination, autoimmune serologic testing, and chest radiographic imaging, but the importance of a comprehensive environmental, avocational, occupational, and medication-use history cannot be overstated and is likely the single most important factor responsible for achieving the best possible outcomes for patients.

Prevalence and reactivity of anti-melanoma differentiation-associated gene 5 (anti-MDA-5) autoantibody in Brazilian patients with dermatomyositis

BACKGROUND

There have been no studies to date on the frequency and reactivity of aanti-melanoma differentiation-associated gene 5 (anti-MDA-5) in samples from the Brazilian population with dermatomyositis.

OBJECTIVES

To analyze this autoantibody in the Brazilian population.

METHODS

This was a single-center cross-sectional study in which 131 consecutive adult patients (109 dermatomyositis and 22 clinically amyopathic dermatomyositis) with active disease were evaluated from 2000 to 2016. Analysis of the anti-MDA-5 autoantibody was performed by ELISA.

RESULTS

The presence of this autoantibody was observed in 14.7% and 22.7% of patients with dermatomyositis and clinically amyopathic dermatomyositis, respectively. In the case of dermatomyositis, the autoantibody was associated less frequently with Raynaud's phenomenon and periungual hyperemia (P<0.05). In clinically amyopathic dermatomyositis, the presence of this autoantibody was not associated statistically with any demographic, clinical, laboratory, or imaging characteristics.

STUDY LIMITATIONS

The cross-sectional study design did not allow establishing a temporal correlation between anti-MDA-5 autoantibody and various study variables. In addition, pulmonary function tests were not performed in the patients.

CONCLUSIONS

The frequency of anti-MDA-5 autoantibody was comparable to that of other populations with dermatomyositis, but with a different reactivity than described in the literature. In addition, there was a phenotypic variability between our patients with clinically amyopathic dermatomyositis and those described in the literature. Further studies are needed to confirm the current study's findings and elucidate this autoantibody's reactivity in Brazilians with idiopathic inflammatory myopathies.

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.

Combined usage of extracorporeal membrane oxygenation and double filtration plasmapheresis in amyopathic dermatomyositis patient with severe interstitial lung disease: A case report

RATIONALE

We report a man with amyopathic dermatomyositis (ADM) complicated by severe interstitial lung disease (ILD) received extracorporeal membrane oxygenation (ECMO) in combination with double filtration plasmapheresis (DFPP). This is the first report of the utility of ECMO in combination with DFPP in ADM related ILD in adults.

PATIENT CONCERNS

A 48-year-old man who was previously healthy had a 2-month history of cough and shortness of breath, which aggravated in 5 days.

DIAGNOSES

Amyopathic dermatomyositis and complicated by severe interstitial lung disease.

INTERVENTIONS

ECMO was giving when the patient suffered acute respiratory failure. Though corticosteroids was giving, primary disease was still developing with relapses of spontaneous pneumomediastinum and pneumothorax. Then, DFPP treatment was initiated.

OUTCOME

After the treatments above, the patient's clinical condition improved with the reduction of bilateral interstitial infiltrates and improvement of lung compliance. Unfortunately, he discontinued the treatment because of the financial problem.

LESSONS

When get a rapid progressive interstitial lung disease for no apparent reason, amyopathic dermatomyositis should be considered, especially with suspected skin lesions. ECMO, in combination with DFPP, should be considered as a supportive therapy and initiated early in patients in acute respiratory failure secondary to ADM-ILD. Prompt initiation of DFPP in dermatomyositis patients with ILD might help reduce the occurrence of spontaneous pneumomediastinum or pneumothorax.

Successful treatment of plasma exchange for rapidly progressive interstitial lung disease with anti-MDA5 antibody-positive dermatomyositis: A case report

RATIONALE

As the initial treatment of rapidly progressive interstitial lung disease (RPILD) with antimelanoma differentiation-associated gene 5 antibody (anti-MDA5 Ab)-positive dermatomyositis (DM) patients, a combination of corticosteroids, cyclophosphamide, and calcineurin inhibitor is recommended. However, some of these patients have poor prognoses despite such intensive treatment. Other more effective treatments are desired. We report the case of an anti-MDA5 Ab-positive DM patient who had developed RPILD despite intensive treatments; she was treated successfully by a short-term plasma exchange (PE).

PATIENT CONCERNS

A 71-year-old Japanese woman was admitted to the rheumatology department of another hospital with progressive muscle weakness of the limbs and erythema on both upper eyelids and the fingers of both hands. She was suspected of having classical DM (CDM) based on the findings of typical skin and myositis. Although a chest computed tomography (CT) examination showed no findings of interstitial pneumonia at the first visit to the department, she newly presented interstitial pneumonia during her admission and her anti-MDA5 Ab titer was elevated.

DIAGNOSES

She was diagnosed with interstitial lung disease (ILD) with anti-MDA5 Ab-positive DM.

INTERVENTIONS

She was treated with 1000 mg of methyl-prednisolone pulse, 500 mg of intravenous cyclophosphamide therapy (IVCY) followed by prednisolone 40 mg/day with tapering, and oral cyclosporine 200 mg/day. However, her interstitial pneumonia worsened with increasing breathing difficulty and an increasing serum ferritin level. She was transferred to our department, and we initiated PE as an additional treatment.

OUTCOMES

After the PE treatment, all laboratory findings, for example, ferritin, KL-6, and the titer of anti-MDA5 Ab showed marked improvement, and the patient's skin symptoms and active interstitial pneumonia were relieved.

LESSONS

Our patient's case suggests that PE may be effective for RPILD in anti-MDA5 Ab-positive DM patients.

Anti-MDA5 antibody as a potential diagnostic and prognostic biomarker in patients with dermatomyositis

The presence of anti-MDA5 antibodies in serum represents an important biomarker in the diagnosis and prediction of prognosis for patients with idiopathic inflammatory myopathies (IIMs). Due to conflicting results that have been reported regarding the detection of anti-MDA5 antibodies, the goal of this study was to assess a potential association between the presence of anti-MDA5 antibodies and dermatomyositis/polymyositis (DM/PM), as well as the diagnostic and prognostic values of anti-MDA5 antibodies for DM/PM. For this, a review of literature published prior to October 15, 2016 was conducted. Eight studies with 286 PM patients and 216 healthy controls and nine studies with 628 DM patients and 221 healthy controls were selected according to specific inclusion criteria. The outcomes of these studies revealed that the presence of anti-MDA5 antibodies was associated with DM, especially CADM, and not with PM. Furthermore, the pooled sensitivity, specificity, and area under the curve (AUC) values were 0.62 (95% confidence interval (CI): 0.52–0.70), 1.00 (95% CI: 0.97–1.00), and 0.9381 for CADM patients versus healthy controls when an immunoprecipitation method was used. The presence of anti-MDA5 antibodies was also found to be significantly associated with an increased risk of death in DM (relative risk = 3.32, 95% CI: 1.65–6.67, P = 0.001). These findings suggest that anti-MDA5 antibodies correlate with DM and could be used as a biomarker in the clinical diagnosis of CADM. The presence of anti-MDA5 antibodies was also associated with poor prognosis regarding the overall survival of patients with DM.

The Serum Ferritin Level Is Associated with the Treatment Responsivity for Rapidly Progressive Interstitial Lung Disease with Amyopathic Dermatomyositis, Irrespective of the Anti-MDA5 Antibody Level

We report the case of a 61-year-old woman with rapidly progressive interstitial lung disease caused by clinically amyopathic dermatomyositis. Both the serum ferritin and anti-melanoma differentiation-associated gene 5 (MDA5) antibody levels were elevated at the time of admission. Despite intensive treatment with corticosteroids, immunosuppressants, immunoglobulins and polymyxin B direct hemoperfusion, the patient died 75 days after symptom onset. Over the course of treatment, the anti-MDA5 antibody level continually decreased, while the serum ferritin level increased, suggesting that sequential measurements of the serum ferritin level might be useful for evaluating the treatment responsivity, irrespective of the anti-MDA5 antibody level.

Clinically amyopathic dermatomyositis associated with anti-MDA5 antibody

Clinically amyopathic dermatomyositis (CADM) is a rare entity that presents with cutaneous manifestations of classic dermatomyositis but without muscle weakness or abnormal muscle enzymes. It is more common in young white and Asian females. A subset of patients with CADM has a specific antibody known as anti-MDA5. These patients have a more aggressive course with distinct cutaneous features, pulmonary involvement and early death. Here, we present the case of a 64-year-old Caucasian male with no significant medical history who was admitted with marked weight loss and a painful rash for 6 months. Patient had no muscle weakness and his rash was characteristic of classic dermatomyositis. Skin biopsy was suggestive of dermatomyositis but muscle enzymes were normal. His serum was positive for anti-MDA5 antibody. Extensive workup failed to detect any malignancy but he did show non-specific interstitial pneumonia. He was treated with prednisone and mycophenolate with good clinical response.

Clinical effects of direct hemoperfusion using a polymyxin B-immobilized fiber column in clinically amyopathic dermatomyositis-associated rapidly progressive interstitial pneumonias

Background

Rapidly progressive interstitial pneumonias (RPIPs) associated with clinically amyopathic dermatomyositis (CADM) are highly resistant to therapy and have a poor prognosis. Multimodal therapies, including direct hemoperfusion using a polymyxin B-immobilized fiber column (PMX-DHP), have a protective effect on RPIPs. We evaluated the effects of PMX-DHP on CADM-associated RPIPs.

Methods

We retrospectively enrolled 14 patients with CADM-associated RPIPs and acute respiratory failure treated with PMX-DHP, corticosteroids, and immunosuppressive agents. Clinical manifestations were compared between survivors and non-survivors at 90 days after PMX-DHP.

Results

The survival rate at 90 days after PMX-DHP was 35.7% (5/14). Before PMX-DHP, the survivor group exhibited a significantly higher PaO₂/FiO₂ (P/F) ratio and serum surfactant protein-D (SP-D) levels and significantly lower lactate dehydrogenase (LDH) and ferritin levels than the non-survivor group. Platelet counts were significantly decreased after PMX-DHP therapy in both groups, but remained higher in the survivor group than the non-survivor group over the course of treatment. Anti-melanoma differentiation-associated gene 5 (MDA-5) antibody positive patients demonstrated a poor 90-day survival rate, lower platelet counts and P/F ratio, and higher LDH levels than anti-MDA-5 antibody negative patients.

Conclusions

CADM-associated RPIPs with anti-MDA-5 antibody is associated with a very poor prognosis. A higher P/F ratio and SP-D level, lower LDH and ferritin levels, higher platelet counts, and anti-MDA-5 antibody negativity are important prognostic markers in patients with CADM-associated RPIPs treated with PMX-DHP.

Neutrophil extracellular traps may contribute to interstitial lung disease associated with anti-MDA5 autoantibody positive dermatomyositis

In dermatomyositis (DM), anti-melanoma differentiation-associated gene 5 (MDA5) autoantibody (autoAb) marks a subtype with low grade or absent muscle inflammation but frequent and rapidly progressive interstitial lung disease (ILD). The pathogenesis of ILD remains poorly unknown. The aim of the study is to explore whether neutrophil extracellular traps (NETs) are involved in the development of ILD in DM patients with anti-MDA5 autoAb. Patients with clinically amyopathic dermatomyositis (CADM, n = 20), classic dermatomyositis (cDM, n = 30), polymyositis (PM, n = 20), and healthy controls (HC, n = 20) were enrolled. Anti-MDA5 autoantibody and Krebs von den Lungen-6 (KL-6) were detected by ELISA. Circulating levels of NETs were assessed by the quantification of both serum cell-free DNA (cfDNA) and LL-37 (cathelicidin LL-37). Immunofluorescent staining was used to visualize NETs ex vivo. The elevated circulating NETs level was detected in DM patients with ILD complication. Compared to anti-MDA5 Ab^- DM patients, anti-MDA5 Ab⁺ DM patients had the higher concentrations of serum cfDNA (293 ± 69 vs 252 ± 63 ng/ml; P = 0.035) and serum LL-37 (0.6 ± 1.0 vs 0.2 ± 0.2 ng/ml; P = 0.026). Positive correlations were established between serum levels of cfDNA and KL-6 in DM patients (r _s = 0.4422, P = 0.0003). anti-MDA5 Ab⁺ sera, other than anti-MDA5 Ab^- sera, could induce greater numbers of normal neutrophils to form NETs in vitro. These data suggest that aberrant NETs formation may be involved in the pathogenesis of ILD in DM patients with anti-MDA5 autoAb.

In vivo measurement of membrane permeability and myofiber size in human muscle using time-dependent diffusion tensor imaging and the random permeable barrier model

The time dependence of the diffusion coefficient is a hallmark of tissue complexity at the micrometer level. Here we demonstrate how biophysical modeling, combined with a specifically tailored diffusion MRI acquisition performing diffusion tensor imaging (DTI) for varying diffusion times, can be used to determine fiber size and membrane permeability of muscle fibers in vivo. We describe the random permeable barrier model (RPBM) and its assumptions, as well as the details of stimulated echo DTI acquisition, signal processing steps, and potential pitfalls. We illustrate the RPBM method on a few pilot examples involving human subjects (previously published as well as new), such as revealing myofiber size derived from RPBM increase after training in a calf muscle, and size decrease with atrophy in shoulder rotator cuff muscle. Finally, we comment on the potential clinical relevance of our results. Copyright © 2016 John Wiley & Sons, Ltd.

Childhood Arthritis and Rheumatology Research Alliance consensus clinical treatment plans for juvenile dermatomyositis with skin predominant disease

BACKGROUND

Juvenile dermatomyositis (JDM) is the most common form of the idiopathic inflammatory myopathies in children. A subset of children have the rash of JDM without significant weakness, and the optimal treatments for these children are unknown. The goal of this study was to describe the development of consensus clinical treatment plans (CTPs) for children with JDM who have active skin rashes, without significant muscle involvement, referred to as skin predominant JDM in this manuscript.

METHODS

The Children's Arthritis and Rheumatology Research Alliance (CARRA) is a North American consortium of pediatric rheumatology health care providers. CARRA members collaborated to determine consensus on typical treatments for JDM patients with skin findings without significant weakness, to develop CTPs for this subgroup of patients. We used a combination of Delphi surveys and nominal group consensus meetings to develop these CTPs.

RESULTS

Consensus was reached on patient characteristics and outcome assessment, and CTPs were developed and finalized for patients with skin predominant JDM. Treatment option A included hydroxychloroquine alone, Treatment option B included hydroxychloroquine and methotrexate, and Treatment option C included hydroxychloroquine, methotrexate and corticosteroids.

CONCLUSIONS

Three CTPs were developed for use in children with skin predominant JDM, which reflect typical treatment approaches. These are not considered to be specific recommendations or standard of care. Using the CARRA network and prospective data collection, we will be able to apply statistical methods in the future to allow comparisons of JDM patients following these consensus treatment plans.

Anti-MDA5-Positive Dermatomyositis Presenting as Fever of Unknown Origin

Dermatomyositis is a chronic systemic autoimmune disease characterized by inflammatory infiltrates in the skin and muscle. The wide variability in clinical and serologic presentation poses a diagnostic challenge for the internist. Appreciation of the clinical variants of dermatomyositis allows for expedient diagnosis and avoidance of diagnostic error. We illustrate these challenges with the case of a 51-year-old Vietnamese-American man who initially presented with fever of unknown origin in the absence of overt skin and muscle manifestations. The diagnosis of dermatomyositis was not evident on several clinical encounters due to the absence of these hallmark symptoms. We review the variable clinical manifestations of a subtype of dermatomyositis associated with an autoantibody against melanoma differentiation-associated protein 5 (anti-MDA5) and suggest consideration of dermatomyositis as a diagnosis in patients presenting with systemic illness and markedly elevated ferritin, even in the absence of elevated muscle enzymes and classic autoantibodies.

Amyopathic Dermatomyositis: A Concise Review of Clinical Manifestations and Associated Malignancies

Amyopathic dermatomyositis is a rare, idiopathic, connective tissue disease that presents with dermatologic lesions of classic dermatomyositis but lacks the myopathy of this disease. Cutaneous manifestations may include Gottron's sign, heliotrope rash, and characteristic patterns of poikiloderma. There is a substantial risk for developing interstitial lung disease or malignancy in patients with amyopathic dermatomyositis. A literature review of amyopathic dermatomyositis was performed using the PubMed medical database. The key features of amyopathic dermatomyositis, including autoantibodies, clinical presentation and dermatologic manifestations, epidemiology, history, associated malignancies, management, and pathogenesis, are summarized in this review. Cancer (solid tumor) (73/79, 89 %) and hematologic malignancies (9/79, 11 %) were reported in 79 patients, with three patients having more than one malignancy. In addition, there were six patients with amyopathic dermatomyositis who had tumor of unknown primary, and eight patients with cancer-associated amyopathic dermatomyositis for whom no additional details were provided. From the group of 73 tumors for whom primary origin and sex were available, malignancy of the genitourinary organs (24/73, 33 %), aerorespiratory organs (15/73, 21 %), and breast (14/73, 19 %) were the most commonly observed solid organ tumors. Tumors of the genitourinary organs (15/48, 31 %) and breast (14/48, 29 %) were the most frequent neoplasms in women, accounting for 29 of 48 (60 %) cancers, with the most common sites being breast (14/48, 29 %), ovary (8/48, 17 %), and cervix or uterus (5/48, 10 %). In men, tumors of the aerorespiratory (9/25, 36 %) and genitourinary (9/25, 36 %) tracts were the most common neoplasms, accounting for 72 % (18/25) of cancers; the most common sites of primary malignancy were nasopharyngeal (6/25, 24 %), bladder (4/25, 16 %), and either colorectal, lung or prostate cancer (three cancers each, 12 %). In summary, the search for an undiagnosed associated malignancy in patients with amyopathic dermatomyositis should focus towards the organs most frequently affected. Similar to classic dermatomyositis, ovarian and nasopharyngeal cancers are also common in amyopathic dermatomyositis. However, in contrast to lung cancer, which is the most frequent malignancy associated with classic dermatomyositis, breast cancer was the most common type of malignancy reported in patients with amyopathic dermatomyosotis.

An Autopsy Case of Anti-melanoma Differentiation-associated Gene-5 Antibody-positive Clinical Amyopathic Dermatomyositis Complicated by Rapidly Progressive Interstitial Lung Disease

A 62-year-old man presented with heliotrope rash, Gottron's sign, and mild muscle weakness. Both of his lung fields showed interstitial changes that worsened rapidly. He was diagnosed with clinical amyopathic dermatomyositis with rapidly progressive interstitial lung disease. The patient died of respiratory failure, despite the administration of immunosuppressive therapy. Autopsy revealed diffuse alveolar damage. An antibody analysis, which was performed postmortem, detected the presence of anti-melanoma differentiation-associated gene (MDA)-5 antibodies. Clinicians should note the clinical, radiologic, and serologic findings to predict anti-MDA-5 antibody-associated rapidly progressive interstitial lung disease.

Clinically amyopathic dermatomyositis: clinical features, response to medications and malignancy-associated risk factors in a specific tertiary-care-centre cohort

BACKGROUND

Clinically amyopathic dermatomyositis (CADM) is a subset of dermatomyositis (DM) characterized by the typical DM cutaneous manifestations but without myositis. There is a relative paucity of characterized cases of CADM in the peer-reviewed medical literature.

OBJECTIVES

To characterize the clinical features, response to medications and malignancy-associated risk factors of patients with CADM with available baseline data seen at a single tertiary-care centre.

METHODS

A retrospective review was undertaken of 44 patients with CADM with available clinical and serological data prior to onset of treatment.

RESULTS

Patients with CADM comprised 18% of all patients with DM with baseline data available at our institution. Although the majority of patients showed improvement with the first prescribed treatment, most required additional medications to control their CADM. Six of 44 patients had an associated malignancy. Photosensitivity and periungual erythema were found to be associated with absence of malignancy (P = 0·03 and P = 0·02, respectively). Patients with malignancy-associated CADM were found to be more likely to have a cutaneous response with the first prescribed treatment than patients without malignancy (P = 0·04).

CONCLUSIONS

CADM represents a significant subset of the DM population. As with classic DM, the cutaneous manifestations of CADM often represent a therapeutic challenge. A subset of patients with CADM has underlying malignancies, and these may differ from those typically associated with classic DM. Differences in serological abnormalities, cutaneous manifestations and response to first treatment among patients with CADM with and without malignancy were found, and suggest distinct pathophysiologies among CADM subsets. Characterization of this cohort expands the knowledge about this unique DM subset.

MDA5-positive dermatomyositis: an uncommon entity in Europe with variable clinical presentations

Clinically amyopathic dermatomyositis (CADM), described almost 50 years ago, is defined on the basis of still not validated criteria and characterized by skin findings almost without muscle weakness. Autoantibodies directed against the cytosolic pathogen sensor MDA5 (CADM 140) can mark this subtype of dermatomyositis which has been reported to associate, in particular ethnic groups, with severe progressive interstitial lung disease, poor prognosis and an hyperferritinemic status resembling hemophagocytic-like syndromes. MDA5 may be relevant in that Interferon-signature claimed to characterize inflammatory myopathies and dermatomyosits itself, but its role is not clear. However, the titre of anti-MDA5 autoantibodies seems to correlate with the outcome. In Caucasian populations the association between anti-MDA5 positive CADM and rapidly progressive interstitial lung disease seems to be weaker, but the limited numbers of patients described so far could explain the lack of statistical significance. As a fact, European patients with circulating anti-MDA5 autoantibodies may be clinically inhomogeneous and exhibit different rates of severity. The two patients affected by anti-MDA5 positive dermatomyositis described hereafter provide a clear example of the extreme variability of the disease in terms of laboratory findings and clinical features.

Interstitial lung diseases in the hospitalized patient

BACKGROUND

Interstitial lung diseases (ILDs) are disorders of the lung parenchyma. The pathogenesis, clinical manifestations, and prognosis of ILDs vary depending on the underlying disease. The onset of most ILDs is insidious, but they may also present subacutely or require hospitalization for management. ILDs that may present subacutely include acute interstitial pneumonia, connective tissue disease-associated ILDs, cryptogenic organizing pneumonia, acute eosinophilic pneumonia, drug-induced ILDs, and acute exacerbation of idiopathic pulmonary fibrosis. Prognosis and response to therapy depend on the type of underlying ILD being managed.

DISCUSSION

This opinion piece discusses approaches to differentiating ILDs in the hospitalized patient, emphasizing the role of bronchoscopy and surgical lung biopsy. We then consider pharmacologic treatments and the use of mechanical ventilation in hospitalized patients with ILD. Finally, lung transplantation and palliative care as treatment modalities are considered. The diagnosis of ILD in hospitalized patients requires input from multiple disciplines. The prognosis of ILDs presenting acutely vary depending on the underlying ILD. Patients with advanced ILD or acute exacerbation of idiopathic pulmonary fibrosis have poor outcomes. The mainstay treatment in these patients is supportive care, and mechanical ventilation should only be used in these patients as a bridge to lung transplantation.

Distinct profiles of myositis-specific autoantibodies in Chinese and Japanese patients with polymyositis/dermatomyositis

The study aims to comprehensively assess the profiles of myositis-specific autoantibodies (MSAs) in Chinese patients with polymyositis (PM)/dermatomyositis (DM) and compare them with a Japanese cohort. One hundred forty-five Chinese patients (68 classic DM, 25 clinically amyopathic DM [CADM], and 52 PM) and 165 Japanese patients (56 classic DM, 52 CADM, and 57 PM) were recruited. MSAs were measured with immunoprecipitation, enzyme-linked immunosorbent assay, or immunoprecipitation-immunoblotting. MSA frequencies were compared. The overall frequency of anti-melanoma differentiation-associated gene 5 (MDA5) antibodies was significantly higher in the Chinese patients than in the Japanese cohort (36.6 % [53/145] versus 15.8 % [26/165], respectively, P < 0.001), whereas the frequencies of anti-signal recognition particle (SRP) antibodies (1.4 % [2/145] versus 7.9 % [13/165], respectively, P = 0.008) and anti-aminoacyl-transfer RNA synthetase (anti-ARS) antibodies (27.6 % [40/145] versus 40 % [66/165], respectively, P = 0.02,) were significantly lower. The significantly lower frequency of anti-ARS antibodies and significantly higher frequency of anti-MDA5 antibodies in the Chinese patients were observed in the classic DM subset (14.7 % [10/68] versus 46.4 % [26/56], respectively, P < 0.001, and 45.6 % [31/68] versus 5.4 % [3/56], respectively, P < 0.001) and CADM subset (8.0 % [2/25] versus 28.8 % [15/52], respectively, P = 0.04, and 88.0 % [22/25] versus 44.2 % [23/52], respectively, P = 0.0002), but not in the PM subset. The first detailed profile of MSAs in Chinese patients with PM/DM was established. The differences in MSA frequencies in the Chinese cohort and Japanese cohort suggest underlying genetic and/or environmental differences between these two populations. Key Messages • A significantly higher frequency of anti-melanoma differentiation-associated gene 5 (MDA5) antibodies was observed in Chinese patients with polymyositis/dermatomyositis (PM/DM) than in Japanese patients. • Our findings suggest that distinct genetic and/or local environmental factors affect Chinese and Japanese patients with PM/DM, who have been considered a "homogeneous" population in previous studies.

Autoantibodies against TIF-1-γ and CADM-140 in Spanish patients with clinically amyopathic dermatomyositis (CADM): clinical significance and diagnostic utility

BACKGROUND

Patients with clinically amyopathic dermatomyositis (CADM) appear to be at risk for developing cancer and interstitial lung diseases, but population data to confirm this hypothesis are limited. Moreover, CADM presents cutaneous and histological findings that may overlap with subacute cutaneous lupus erythematosus (SCLE).

OBJECTIVES

To determine the association between myositis-specific autoantibodies, myositis-associated autoantibodies and CADM in Spanish patients. In addition, to study the usefulness of these autoantibodies in the differential diagnosis between CADM and SCLE.

METHODS

Serum samples were tested for myositis-specific autoantibodies and myositis-associated autoantibodies through immunoprecipitation and other standardized methods.

RESULTS

Anti-CADM-p140 and anti-p155 antibodies were the only myositis-specific autoantibodies found and were associated with interstitial lung diseases and cancer respectively. No myositis-associated autoantibodies were found in CADM. Moreover, clinical subsets and proportions seemed to differ from Asian cohorts, where anti-CADM-p140 is considered a CADM hallmark antibody and a risk factor for the development of interstitial lung disease. Interestingly, anti-SSA was highly associated with SCLE, whereas no myositis-specific autoantibodies were found in this entity.

LIMITATIONS OF THE STUDY

Association between CADM and myositis-specific autoantibodies and differences between CADM and SCLE were tested on a relatively small cohort of patients.

CONCLUSION

There is an association between cancer-associated myositis and interstitial lung diseases and their hallmark autoantibodies in our cohort. In addition, the combined determination of myositis-specific autoantibodies and SSA autoantibodies may help to accurately discriminate SCLE from CADM.

Fulminant systemic capillary leak syndrome due to C1 inhibitor deficiency complicating acute dermatomyositis: a case report

Introduction

Dermatomyositis is a chronic inflammatory disorder characterized by muscular and dermatologic symptoms with variable internal organ involvement. This is the first report on a patient with acute dermatomyositis and fulminant systemic capillary leak syndrome.

Case presentation

A 69-year-old Caucasian woman with chronic dermatomyositis presented with clinical signs of severe hypovolemic shock and pronounced hemoconcentration (hematocrit, 69%). Her colloid osmotic pressure was 4.6mmHg. Following a bolus dose of prednisolone (500mg), fluid resuscitation was initiated. During volume loading, anasarca and acute respiratory distress rapidly developed. Echocardiography revealed an underfilled, hypokinetic, diastolic dysfunctional left ventricle with pericardial effusion but no signs of tamponade. Despite continued fluid resuscitation and high-dosed catecholamine therapy, the patient died from refractory shock 12 hours after intensive care unit admission. A laboratory analysis of her complement system suggested the presence of C1 inhibitor deficiency as the cause for systemic capillary leakage. The post-mortem examination revealed bilateral pleural, pericardial and peritoneal effusions as well as left ventricular hypertrophy with patchy myocardial fibrosis. Different patterns of endomysial/perimysial lymphocytic infiltrations adjacent to degenerated cardiomyocytes in her myocardium and necrotic muscle fibers in her right psoas major muscle were found in the histological examination.

Conclusions

This case report indicates that acute exacerbation of chronic dermatomyositis can result in a fulminant systemic capillary leak syndrome with intense hemoconcentration, hypovolemic shock and acute heart failure. In the presented patient, the cause for diffuse capillary leakage was most probably acquired angioedema, a condition that has been associated with both lymphoproliferative and autoimmunologic disorders.