Antisynthetase Antibodies Research Articles

Clinical features and imaging findings of interstitial lung disease in antisynthetase syndrome

Objective To investigate the clinical features and imaging findings of interstitial lung disease in antisynthetase syndrome(AS-ILD)and to compare the characteristics among AS specificities. Methods A total of 59 cases with AS-ILD at our hospital during the last 5 years were retrospectively reviewed, including anti-Jo1 positive in 37 cases and anti-PL7 positive in 6 cases and anti-PL12 positive in 6 cases and anti EJ positive in 10 cases. There were 14 males and 45 females aged (51±12) years. The clinical features including myositis, arthritis, fever, mechanic's hands , rash, proximal dysphagia, raynaud phenomenon were identified. Two radiologists evaluated the pattern, distribution and the ILD pattern of the lung abnormalities on HRCT findings. Based on the anti synthetase antibody positive subtype, 59 patients could be divided into four groups;then the differences of clinical features and HRCT findings between different subtypes were analyzed. χ2 test was performed for the comparison of the differences between anti-Jo1 antibody positive and the other 3 group. Results (1)Myositis and arthritis were the most common AS manifestations, which were 61.02% (36/59) and 50.85%(30/59) respectively. (2)The lung abnormalities were predominantly basal(91.53%, 54/59) and peripheral(59.32%, 35/59). Ground-grass opacities(79.66%, 47/59)and reticulations(76.27%, 45/59) were found most frequently. Non-specific interstitial pneumonia(NSIP) was the most common HRCT pattern(64.41%, 38/59). (3) As compared with anti-Jo1 positive AS patients, anti-PL12 positive AS patients showed a high rate of traction bronchiectasis at diagnosis(83.33%, 5/6), while the difference was statistically significant(χ2=7.206, P=0.015). The prevalence of pericardial effusion(40.00%, 4/10) was significantly higher in the group of the anti-EJ positive AS patients than that with anti-Jo1 antibody AS(χ2=6.317, P=0.044). Conclusions Myositis and arthritis are the predominant clinical features. NSIP is the most common HRCT pattern in AS-ILD patients. There are some differences of signs among various subtypes, indicating that the difference of fibrosis in the lung and inflammatory reaction in the body being correlated with the AS specificities. Key words: Antisynthetase syndrome; Interstitial lung disease; anti-Jo1 antibody

Myasthenia and antisynthetase antibody syndrome: a case report in Togo

Myasthenia and antisynthetase antibody syndrome: a case report in Togo

Hyperacute muscle weakness in an unusual coexistence of antisignal recognition particle and anti-Mi-2 antibodies

Idiopathic inflammatory myopathies are a heterogeneous group of systemic diseases characterised by variable phenotypes of chronic progressive muscle weakness. Myositis-specific antibodies (MSAs) include antibodies to cytoplasmic signal recognition particle (SRP)...

Clinical Profiles and Prognosis of Patients with Distinct Antisynthetase Autoantibodies.

To compare the clinical characteristics and identify the longterm outcomes of Chinese patients with different antisynthetase antibodies. We investigated retrospectively 124 consecutive patients with antisynthetase syndrome. Medical records, laboratory results, and computed tomography images were obtained. The antisynthetase antibodies we investigated were anti-Jo1 (n = 62), anti-PL7 (n = 31), anti-PL12 (n = 12), and anti-EJ (n = 19). The overall prevalence of interstitial lung disease (ILD) reached 94.4% among study patients. Eleven patients (8.9%) developed rapidly progressive ILD (RP-ILD). Eight patients (6.5%) experienced malignancy. RP-ILD was statistically more prevalent in patients with antisynthetase syndrome with anti-PL7 than those without anti-PL7 (p = 0.028). Anti-Ro52-positive patients with antisynthetase syndrome experienced higher frequency of RP-ILD than those without anti-Ro52 (p = 0.001). Further, anti-PL7-positive patients coexisting with anti-Ro52 exhibited more RP-ILD than those without anti-Ro52 (p = 0.001). Patients with antisynthetase syndrome with RP-ILD had a higher proportion of neutrophils in bronchoalveolar lavage fluid and serum ferritin than those without RP-ILD (p = 0.006 and p = 0.013, respectively). Although no differences were observed between the Kaplan-Meier curves of the 4 antisynthetase antibodies subgroups (p = 0.349), the survival rate of patients with anti-PL7 decreased more rapidly in the early stage of longterm followup compared with those with other antisynthetase antibodies. The presence of RP-ILD, malignancy, and elevated serum ferritin was identified to be associated with poor prognosis in patients with antisynthetase syndrome. Our study investigates the clinical phenotypes and outcomes of patients with antisynthetase syndrome with distinct antisynthetase antibodies and highlights the link between the anti-PL7 antibody and RP-ILD.

Advances in serological diagnostics of inflammatory myopathies.

Inflammatory myopathies are rare diseases. Their diagnosis criteria are historically based on their clinical phenotype (topography of the muscle weakness, presence of skin lesions and/or of extra-skin/muscle signs) and the presence of inflammatory infiltrates on muscle biopsy. However, the recent discovery of different myositis-specific antibodies (MSA) or myositis-associated antibodies (MAA) permitted to revisit these old classifications. This review covers recent findings in clinical and pathological phenotypes regarding prognosis, associated cancer and response to the treatment based on MSA/MAA categorization. Since the mid-1970s, about 20 MSA or MAA were discovered year after year (by immunoprecipitation). Now commercial kits (mainly dot line assays) permit their detection routinely which is clearly a help for the diagnosis but also give some key indications on clinical features, risk of associated cancers and response to the treatments. Overlap myositis is associated with antisynthetase antibodies (Abs) or those associated with sclerodermia (anti-RNP, Ku and PM-ScL). Dermatomyositis is associated with anti-Mi2, small ubiquitin-like modifier activating enzyme (SAE), nuclear matrix protein-2 (NXP2), TIF-1γ or melanoma differentiation-associated gene 5 (MDA5) Abs. Immune-mediated necrotizing myopathies are associated with anti-signal recognition particle (SRP) or 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) Abs. One third of inclusion body myositis' patients also presented anti-cytosolic 5'-nucleotidase 1A (cN1A) Abs. The risk of associated cancers is elevated with anti-TIF-1γ, NXP2 or HMGCR Abs.

Myositis-specific and myositis-associated autoantibodies in Indian patients with inflammatory myositis.

We aimed to study the prevalence and clinical associations of myositis-specific autoantibodies (MSAs) and myositis-associated autoantibodies (MAAs) in a large cohort of Indian patients with idiopathic inflammatory myositis (IIM). Clinical details and serum samples were collected from patients with IIM (satisfying Bohan and Peter Criteria, 1975) and CTD-associated myositis. Sera were analysed for antibodies against SRP, Mi2, Jo1, PL7, PL12, EJ, OJ, Ro52, Ku, Pm-Scl 75 and PM-Scl 100, using immunoblot assay. The cohort comprised 124 patients with IIM (M:F=1:3.6). Fifty-five of them had dermatomyositis (DM), 22 had juvenile dermatomyositis (JDM), 25 had polymyositis (PM) and 22 had connective tissue disease-associated myositis (CTD myositis). Mean disease duration was 10.9months. ANA was positive in 84 (68.9%), and MSAs in 61 (49.2%) patients. Among MSAs, autoantibodies to Mi2, synthetase (Jo1, PL7, PL12, EJ) and SRP were present in 26 (20.9%), 29 (23.4%) and 6 (4.8%) patients, respectively. Prevalence of MAAs was as follows: antibodies to Ro52 in 45 (36.3%), Ku and PM-Scl 75 in 13 (10.5%) and PM-Scl 100 in 5 (4%) patients. Anti-Mi2 antibodies were positively associated with DM (21/55, 38.2%; p<0.0001) and pharyngeal weakness (13/34, 38.2%; p=0.004) and negatively associated with ILD (0/28; p=0.001). ILD and mechanics' hands were significantly more in patients with anti-synthetase antibodies (16/28, 57% and 14/22, 63.6%; p<0.0001). Four of six patients with anti-SRP antibody showed poor response to multiple drugs. Higher prevalence of anti-Mi2 is probably related to higher proportion of patients with DM. Absence of ILD in patients with anti-Mi2 antibody suggests that it may protect against ILD. In Indian populationalso, anti-synthetase antibodies are associated with ILD, and anti-SRP antibodies with poor response to treatment.

Antisynthetase Syndrome: A Review of Etiopathogenesis, Diagnosis and Management

Antisynthetase syndrome is a group of closely related rare diseases which clinically manifest with inflammatory myopathies, interstitial lung disease, inflammatory arthritis, skin hyperkeratosis (mechanic’s hands) and Raynaud phenomenon. The pathophysiology of antisynthetase syndrome is not entirely understood, but genetic predisposition, viral infections and medication use may play a role. Certain antisynthetase antibodies are associated with various clinical presentations and a lower burden of inflammatory myopathies. Patients with antisynthetase syndrome have a worse prognosis than patients with pure inflammatory myopathies mainly because of interstitial lung disease. Future research should further investigate the pathogenesis of antisynthetase syndrome which could identify new therapeutic targets. It will be also important to study whether patients with AS are at increased risk of cancer and whether certain antisynthetase antibodies have any association with the risk of malignancy.

Mechanic’s hands in a woman with undifferentiated connective tissue disease and interstitial lung disease – anti-PL7 positive antisynthetase syndrome: a case report

IntroductionInterstitial lung disease can be idiopathic or occur in the setting of connective tissue diseases. In the latter case it requires a different treatment approach with a better prognosis. Interstitial lung disease can precede the onset of typical connective tissue disease features by many years, and therefore meticulous multidisciplinary follow-up is crucial. This case highlights the diagnostic challenge and the need for intensified attention for subtle clinical features when faced with interstitial lung disease in patients with characteristics of a hitherto undifferentiated connective tissue disease.Case presentationA 44-year-old Caucasian woman presented to our pulmonology department with dyspnea, Raynaud’s phenomenon and subtle swelling of fingers and eyelids. Laboratory analysis and autoantibody screening was negative. She was diagnosed with nonspecific interstitial pneumonia with a concurring undifferentiated connective tissue disease. After four years of stable disease, she presented with rapid pulmonary deterioration, myalgia, periorbital edema, arthritis and a cracked appearance of the radial sides of the fingers of both her hands. This clinical sign was recognized as mechanic’s hands and a specific search for the presence of antisynthetase antibodies was performed. She was found to harbor anti-threonyl-tRNA synthetase antibodies. A diagnosis of antisynthetase syndrome was made and she was treated with glucocorticoids and immunosuppressives.ConclusionsThis case highlights the difficulty in fine-tuning the diagnosis when confronted with a patient with interstitial lung disease and the suspicion of an underlying, yet undifferentiated connective tissue disease. There is a strong need for clinical multidisciplinary follow-up of these patients, with a high level of alertness to rare and specific clinical signs. The diagnosis of the underlying connective tissue disease profoundly influences the management of the interstitial lung disease. Recent data stress that identification of the autoantibody specificity allows for further prognostic stratification and therefore should be pursued.

Diagnostic Utility of Auto-Antibodies in Inflammatory Muscle Diseases

To date, there are four main groups of idiopathic inflammatory myopathies (IIM): polymyositis (PM), dermatomyositis (DM), immune-mediated necrotizing myopathy (IMNM) and sporadic inclusion body myositis; based on clinical presentation and muscle pathology. Nevertheless, important phenotypical differences (either muscular and/or extra-muscular manifestations) within a group persist. In recent years, the titration of different myositis-specific (or associated) auto-antibodies as a diagnostic tool has increased. This is an important step forward since it may facilitate, at a viable cost, the differential diagnosis between IIM and other myopathies. We have now routine access to assays for the detection of different antibodies. For example, IMNM are related to the presence of anti-SRP or anti-HMGCR. PM is associated with anti-synthetase antibodies (anti-Jo-1, PL-7, PL-12, OJ, and EJ) and DM with anti-Mi-2, anti-SAE, anti-TIF-1-γ and anti-NXP2 (both associated with cancer) or anti-MDA5 antibodies (associated with interstitial lung disease). Today, over 30 myositis specific and associated antibodies have been characterised, and all groups of myositis may present one of those auto-antibodies. Most of them allow identification of homogenous patient groups, more precisely than the classical international classifications of myositis. This implies that classification criteria could be modified accordingly, since these auto-antibodies delineate groups of patients suffering from myositis with consistent clinical phenotype (muscular and extra-muscular manifestations), common prognostic (cancer association, presence of interstitial lung disease, mortality and risk of relapse) and treatment responses. Nevertheless, since numerous auto-antibodies have been recently characterised, the exact prevalence of myositis specific antibodies remains to be documented, and research of new auto-antibodies in the remaining seronegative group is still needed.

23. Non-specific interstitial pneumonia and polymyositis as a manifestation of antisynthetase syndrome with anti-EJ antibodies

We present a case of a 48-year-old woman who developed synchronous proximal myopathy and colorectal adenocarcinoma. Muscle biopsy demonstrated an inflammatory necrotizing myopathy, and routine autoimmune screens and paraneoplastic screens were negative. Testing was undertaken for antisynthetase antibodies, demonstrating positivity for anti-EJ antibodies. The patient developed progressive shortness of breath, and shortly thereafter succumbed to bronchopneumonia. Findings at autopsy confirmed the presence of interstitial lung disease, with a non-specific interstitial pneumonia pattern. Antisynthetase syndrome is a systemic autoimmune disease associated with autoantibodies to certain aminoacyl-tRNA synthetases, and is characterized typically by myositis, polyarthritis and interstitial lung disease. Aminoacyl-transfer RNA synthetases are a family of cytoplasmic enzymes that catalyze amino acid attachment to corresponding aminoacyl-tRNAs during the translation phase of protein synthesis. In this case, the autoantibody is to the glycyl-transfer RNA synthetase, one of the rarest described antisynthetase autoantibodies. We present a case of a 48-year-old woman who developed synchronous proximal myopathy and colorectal adenocarcinoma. Muscle biopsy demonstrated an inflammatory necrotizing myopathy, and routine autoimmune screens and paraneoplastic screens were negative. Testing was undertaken for antisynthetase antibodies, demonstrating positivity for anti-EJ antibodies. The patient developed progressive shortness of breath, and shortly thereafter succumbed to bronchopneumonia. Findings at autopsy confirmed the presence of interstitial lung disease, with a non-specific interstitial pneumonia pattern. Antisynthetase syndrome is a systemic autoimmune disease associated with autoantibodies to certain aminoacyl-tRNA synthetases, and is characterized typically by myositis, polyarthritis and interstitial lung disease. Aminoacyl-transfer RNA synthetases are a family of cytoplasmic enzymes that catalyze amino acid attachment to corresponding aminoacyl-tRNAs during the translation phase of protein synthesis. In this case, the autoantibody is to the glycyl-transfer RNA synthetase, one of the rarest described antisynthetase autoantibodies.

Interstitial lung disease as an initial manifestation of dermatomyositis

To explore the clinical features and prognosis of dermatomyositis patients with interstitial lung disease (ILD) as an initial manifestation. Medical records of 184 dermatomyositis inpatients complicated with ILD, admitted into Peking Union Medical College Hospital from January 1999 to January 2013, were retrospectively analyzed. The clinical features, biochemical parameters, positive rates of autoantibodies, radiology, pulmonary function tests, pathology, treatments and prognosis were compared between two subgroups of ILD-initial and non-ILD-initial dermatomyositis. The incidence of ILD of dermatomyositis inpatients was 17%. The average age was 48 ± 12 years and the gender ratio of male-to-female was 63: 121. Eighty eight (47.8%) dermatomyositis patients had ILD as an initial manifestation, including (n = 42, 22.8%) of ILD concomitant dermatomyositis (within 1 month) and (n = 46, 25.0%) of ILD before dermatomyositis with an average ahead time of (11 ± 3) months. Patients of ILD-initial dermatomyositis had a higher incidence of dyspnea on exertion, cough and lung crackles, but there were lower incidences of heliotrope rash, chest V area rash, shawl sign and joint involvement than non-ILD-initial dermatomyositis (P < 0.05). The positive rate of anti-Jo-1 antibodies of ILD-initial dermatomyositis group was 13.6%. The main performances of ILD-initial dermatomyositis on pulmonary function tests were diffusing and restrictive ventilation impairment. And there was a lower diffusing rate of carbon monoxide than non-ILD-initial dermatomyositis group (P < 0.01). Organic and non-specific interstitial pneumonias were the major clinical pathology types of ILD-initial dermatomyositis. The mortality rate of ILD-initial dermatomyositis patients was 19.3% and there was no significant difference from non-ILD-initial dermatomyositis (P > 0.05). The main course of ILD-initial dermatomyositis was respiratory failure due to progressive ILD (n = 13, 76.5%). ILD as an initial manifestation is a common complication and a major mortality cause of dermatomyositis inpatients. And the frequent clinical pathology types are organic and non-specific interstitial pneumonias. Symptoms of skin and muscle, creatine kinase and anti-synthetase antibodies should be closely monitored.

Interstitial lung disease associated with the idiopathic inflammatory myopathies and the antisynthetase syndrome: recent advances.

To highlight recent advances in understanding the clinical spectrum, pathogenesis, and treatment of interstitial lung disease associated with inflammatory myositis and the antisynthetase syndrome. In recent years, serologic tests to identify the less common antisynthetase antibodies and the anti-MDA-5 antibody have become commercially available. As a result, several large, retrospective analyses have illustrated both the pulmonary and non-pulmonary features associated with the antisynthetase syndrome and myositis-related interstitial lung disease. Notably, there is now a better appreciation for the heterogeneity of these syndromes and the prognostic value in accurately identifying the associated autoantibodies. Human cytokine profiling and murine models of muscle inflammation suggest that tRNA synthetases themselves may act to trigger an initial innate immune response, thus offering new insights into the pathophysiology of these diseases. Finally, although randomized clinical trials in patients with myositis-associated interstitial lung disease have not occurred, new observational studies suggest that cyclosporine, tacrolimus, and rituximab may be effective treatment options. Recent research has provided a better understanding of the phenotype and prognosis that define interstitial lung disease in the setting of myositis and the antisynthetase syndrome. Although several therapeutic agents demonstrate promise, randomized trials are needed in order to establish the best clinical approach in these patients. Furthermore, additional research into the pathophysiology of this disease will be necessary to develop newer, more targeted therapeutics.

Myofiber HLA-DR expression is a distinctive biomarker for antisynthetase-associated myopathy.

ObjectivesTo assess the value of major histocompatibility complex (MHC) class II antigen (HLA-DR) expression to distinguish anti-synthetase myopathy (ASM) from dermatomyositis (DM).MethodsMuscle biopsies from patients with ASM (n = 33), DM without anti-synthetase antibodies (ASAb) (n = 17), and normal muscle biopsy (n = 10) were first reviewed. ASAb included anti-Jo1 (26/33), anti-PL12 (4/33), anti-PL7 (2/33), and anti-EJ (1/33). Immunohistochemistry was performed for MHC-I/HLA-ABC, MHC-II/HLA-DR, membrane attack complex (C5b-9), neural cell adhesion molecule (NCAM)/CD56 expression, and inflammatory cell subsets. Twenty-four ASM and 12 DM patients from another center were added for HLA-DR evaluation.ResultsUbiquitous myofiber HLA-ABC expression was equally observed in ASM and DM (93.9% vs 100%, NS). In contrast, myofiber HLA-DR expression was found in 27/33 (81.8%) ASM (anti-Jo1: 23/26, 88.5%; others: 5/7, 71.4%) vs 4/17 (23.5%) DM patients (p < 0.001). HLA-DR was perifascicular in ASM, a pattern not observed in DM. In addition, C5b-9 deposition was observed on sarcolemma of non-necrotic perifascicular fibers in ASM, while, in DM, C5b-9was mainly detected in endomysial capillaries. CD8 cells were more abundant in ASM than in DM (p < 0.05), and electively located in perimysium or in perifascular endomysium. HLA-DR expression correlated positively with the CD8+ cells infiltrates. Strictly similar observations were made in the confirmatory study.ConclusionASM is characterized by strong myofiber MHC-II/HLA-DR expression with a unique perifascicular pattern, not described so far. HLA-DR detection must be included for routine myopathological diagnosis of inflammatory/dysimmune myopathies. HLA-DR expression in ASM may indicate a specific immune mechanism, possibly involving IFNγ.Electronic supplementary materialThe online version of this article (doi:10.1186/s40478-014-0154-2) contains supplementary material, which is available to authorized users.

Clinical and pathologic differences in interstitial lung disease based on antisynthetase antibody type

Interstitial lung disease (ILD) is a common extramuscular manifestation of the idiopathic inflammatory myopathies (IIMs), dermatomyositis (DM) and polymyositis (PM). Patients with antisynthetase antibodies (ASA) demonstrate some or all of the features of the antisynthetase syndrome including IIM and ILD. It has been hypothesized that the clinical expression of antisynthetase syndrome varies between specific ASAs. We sought to determine whether the myositis-associated ILD (MA-ILD) phenotype differs based on the presence of ASAs and by ASA subtype. A cross-sectional and longitudinal analysis of consecutive patients enrolled at the Johns Hopkins Myositis Center with ILD in the setting of clinically diagnosed autoimmune myositis was conducted. Seventy-seven subjects were included; 36 were ASA negative, 28 were anti-Jo1 positive, and 13 were non-Jo1 ASA positive (5 anti-PL-12, 4 anti-PL-7, 2 anti-EJ, and 2 anti-OJ). Non-Jo1 ASA positive participants were more likely to be African-American than Caucasian as compared to both the anti-Jo1 positive (p=0.01) and ASA negative groups (p<0.01). ASA negative participants had better mean forced vital capacity percent predicted (FVC%) and total computed tomography scores over time compared to those with anti-Jo1 after controlling for potential confounders. ASA status was significantly different by race. Those with anti-Jo1 antibodies had worse lung function and CT scores over time compared to those without detectable antisynthetase antibodies. Further prospective study in a larger cohort is needed to determine whether these apparent antibody-specific differences in demographics and manifestations of disease translate into meaningful disparities in clinical outcomes.

A case of myositis with immunological background associated with statin use

Abstract Statins might cause and/or aggravate the immune-mediated myositis in patients on long-term, stable treatment. We provide a case of polymyositis with an immunological background and gastrointestinal and urinary manifestations in patient on long-term, stable atorvastatin treatment for the past six years. The diagnose of polymyositis was established based on clinical symptoms and signs, electromyography and laboratory test results (elevated aspartate aminotransferase 279 U/L, reference range 0–40 U/L; alanine aminotransferase 198 U/L, 0–33 U/L; lactate dehydrogenase 2200 U/L, 103-227 U/L; creatine kinase 7820 U/L, 15–84 U/L; and positive antinuclear antibodies test, titer of 1:160, with suspect antisynthetase antibodies). Polymyositis was probably related to atorvastatin treatment (Naranjo score, 5). Other probable causes of the myositis were rejected. Coricosteroid therapy, methotrexate and supplementation with vitamin D did not improve the condition. The patient remained bedridden and died two months after the hospital discharge due to the acute myocardial infarction.

Brief Report: Antisynthetase Syndrome–Associated Myocarditis

BackgroundThe antisynthetase (AS) syndrome is characterized by autoimmune myopathy, interstitial lung disease, cutaneous involvement, arthritis, fever, and antibody specificity. We describe 2 patients with AS syndrome who also developed myocarditis, depressed biventricular function, and congestive heart failure. Methods and ResultsBoth patients were diagnosed with AS syndrome based on clinical manifestations, detection of serum AS antibodies, and myositis confirmation with the use of skeletal muscle magnetic resonance imaging and skeletal muscle biopsy. In addition, myocarditis resulting in heart failure was confirmed with the use of cardiac magnetic resonance imaging and from endomyocardial biopsy findings. After treatment for presumed AS syndrome–associated myocarditis, one patient recovered and the other patient died. ConclusionsAS syndrome is a rare entity with morbidity and mortality typically attributed to myositis and lung involvement. This is the first report of AS syndrome–associated myocarditis leading to congestive heart failure in 2 patients. Given the potentially fatal consequences, myocarditis should be considered in patients with AS syndrome presenting with heart failure.

Síndrome antisintetasa. Informe de un caso

Introduction: The antisynthetase syndrome has been described in adults with an average age of 45 to 60 years, but it can affect children, predominantly females. Its features include myositis, polymyositis, interstitial lung disease and the presence of aminoacyl tRNA antibodies of which the Anti Jo-1 is the most common. Case Report: A 6 year old girl had a two year history of fever, arthritis syndrome, progressive muscle weakness, Raynaud’s phenomenon, myalgia, malar heliotrope rash, Gottron’s papules and “mechanic hands”, tachypnea, finger clubbing. The patient was oxygen-dependent. X-ray and computerized axial tomography showed images suggestive of lung fibrosis. She had elevated creatine: 4530 IU/mL, and positive Jo-1 antibody. There was a myopathic electromyography pattern. A muscle biopsy was compatible with polymyositis. Juvenile dermatomyositis with anti-synthetase syndrome was diagnosed. She was treated with methylprednisolone, prednisone, intravenous human immunoglobulin and cyclophosphamide. During the first year of treatment her muscle strength was recovered, fever and skin lesions disappeared, respiratory function became normal and there was no need for oxygen. Discussion. The antisynthetase syndrome includes polymyositis and dermatomyositis, interstitial lung disease, polyarthritis, Raynaud’s phenomenon, “mechanic hands” and the presence of serum anti-synthetase antibodies. Treatment should be comprehensive and holistic, in order to restore lung capacity, prevent progression of damage and improve life quality.

SAT0318 Antisynthetase Syndrome: Clinical and Serological Characteristics at Disease Onset

BackgroundAntisynthetase syndrome (ASS) is a rare condition characterized by the presence of one or more of the following clinical features: arthritis, Raynaud's phenomenon, “mechanic's hands”, interstitial lung disease and polymyositis,...

OP0290 Long Time Experience with Rituximab in the Antisynthetase Syndrome with Severe Lung Disease

BackgroundThe Antisynthetase syndrome (ASS) has a high frequency of interstitial lung disease (ILD) leading to increased morbidity and thereby needs for aggressive immunotherapy [1].ObjectivesTo evaluate efficacy and safety with Rituximab-treatment...

Pneumopathie infiltrante diffuse associée à une dermatomyosite amyopathique avec auto-anticorps anti-MDA5

Amyopathic dermatomyositis associated with anti-MDA5 autoantibodies is a rare and very recently described clinical entity. A 58-year-old woman was admitted with subacute onset of dyspnea (NYHA class IV) associated with cough, oligoarthritis of the wrists, myalgia and intermittent fever. Examination demonstrated skin lesions with heliotrope rash, Gottron's papules, "mechanics hands", and basal inspiratory crackles on lung auscultation. Pulmonary function tests showed a restrictive ventilatory defect, with decreased carbon monoxide diffusion capacity and marked hypoxemia (PaO2 61 mmHg). The chest high-resolution computed tomography appearances were consistent with organizing pneumonia. Bronchoalveolar lavage differential cell count demonstrated 22 % neutrophils. Serum creatine kinase and electromyography were normal ; the serum ferritin level was elevated. Antinuclear antibodies were present and anti-MDA5 autoantibodies were identified. Significant improvement was obtained with systemic corticosteroids, later converted to mycophenolate mofetil as a steroid-sparing agent. Amyopathic dermatomyositis associated with anti-MDA5 autoantibodies shares some characteristics with those associated with anti-synthetase antibodies. Muscular involvement may be mild or absent. Early diagnosis and treatment may improve outcome.