Antisynthetase syndrome and malignancy: our experience

Anti-synthetase Syndrome That Relapsed with Pulmonary Arterial Hypertension and Malignancy

A 69-year-old man with a history of anti-synthetase antibody-positive polymyositis and interstitial lung disease (ILD) stable for more than 20 years suddenly developed pulmonary artery hypertension (PAH) with a mean PA pressure of 46 mmHg. At this stage, ILD was mild, but it became acutely exacerbated later, and high-dose corticosteroid and intravenous cyclophosphamide ameliorated both PAH and ILD. The tricuspid regurgitation pressure gradient decreased from 80 to 49 mmHg and ILD recovered almost completely. During a systemic examination, bone metastatic cancer of unknown origin was found. We herein report the relationship between anti-synthetase syndrome (ASS) and PAH as well as ASS and malignancy.

A narrative review of interstitial lung disease in anti-synthetase syndrome: a clinical approach

Anti-synthetase syndrome (AS) is a rare autoimmune disorder characterized by the presence of aminoacyl-transfer RNA synthetase antibodies in conjunction with clinical features such as interstitial lung disease (ILD), Raynaud's phenomenon, nonerosive arthritis, and myopathy. AS distinguishes itself from other inflammatory myopathies by its significant lung involvement and rapidly progressive interstitial lung disease (AS-ILD), therefore the management of AS-ILD requires careful clinical, serologic and radiologic assessment. Glucocorticoids are considered the mainstay of therapy; however, additional immunosuppressive agents are often required to achieve disease control. Patient prognosis is highly dependent on early diagnosis and symptom recognition as the antibody profile is thought to influence therapy response. Since progressive ILD is the leading cause of morbidity and mortality, this review will discuss the clinical approach to patient with suspected AS, with particular emphasis on diagnosis and management of AS-ILD.

Antisynthetase syndrome - much more than just a myopathy

The aim of the study was to summarize current knowledge on antisynthetase syndrome (ASS), including its epidemiology, pathogenesis, proposed so far diagnostic criteria, heterogeneity of clinical manifestations, prognostic factors and therapeutic possibilities. PubMed database was screened for "antisynthetase syndrome" OR "antisynthetase antibodies" between February and April 2020. Aminoacyl-tRNA synthetases participate in the immune system activation as antigens, but also serve chemoattractive and cytokine-resembling roles, initiating innate and adaptive pathways. Exposure to various inhaled antigens may induce the autoimmune cascade leading to ASS. NK cells with its impaired INF-y production as well as formation of NETs by neutrophils contribute to pathogenesis. The prevalence of symptoms vary significantly depending on the study with muscular, articular and pulmonary involvement being the most frequently observed. Although classified as subtype of idiopathic inflammatory myopathies, myositis may not necessarily be the prominent manifestation. Since clinical presentation is heterogeneous and symptoms can emerge gradually, ASS could be considered as a heterogeneous spectrum rather than a homogenous disease entity. The currently available classification criteria do not fully correspond with the clinical patterns of the disease. Therapy is based on glucocorticosteroids and other immunosuppressive agents. Randomized controlled trials, dedicated for patients with ASS, are needed to form treatment algorithms.

Antisynthetase syndrome: A distinct disease spectrum

The discovery of novel autoantibodies related to idiopathic inflammatory myopathies (collectively referred to as myositis) has not only advanced our understanding of the clinical, serological, and pathological correlation in the disease spectrum but also played a role in guiding management and prognosis. One group of the myositis-specific autoantibodies is anti-aminoacyl-tRNA synthetase (anti-ARS or anti-synthetase) which defines a syndrome with predominant interstitial lung disease, arthritis, and myositis. Autoantibodies to eight aminoacyl-tRNA synthetases have been identified with anti-Jo1 the most common in all of idiopathic inflammatory myopathies. Disease presentation and prognosis vary depending on which anti-aminoacyl-tRNA synthetase antibody is present. In this review, we will discuss the clinical characteristics, overlap features with other autoimmune diseases, prognostic factors, and management of the antisynthetase syndrome.

Clinical manifestations and treatment of antisynthetase syndrome

Antisynthetase syndrome (ASyS) is an autoimmune disease clinically manifested most often by interstitial lung disease, myositis, and arthritis. Raynaud's syndrome, fever, and rashes are also commonly seen. This syndrome is characterized by the highly specific presence of antibodies against various aminoacyl transfer RNA synthetases, including Jo-1 and others. In this chapter, we provide an overview of ASyS, including pathogenesis, common clinical manifestations, and treatment strategies. We discuss the spectrum of disease seen with specific antisynthetase antibodies and examine the differences in phenotype between patients with different antisynthetase antibodies. We outline common treatment strategies, which should generally target the most severe and life- or organ-threatening disease manifestations. Finally, we discuss short- and long-term prognosis in ASyS.

Clinical features and outcome of patients with acute respiratory failure revealing anti-synthetase or anti-MDA-5 dermato-pulmonary syndrome: a French multicenter retrospective study

Background

Anti-synthetase (AS) and dermato-pulmonary associated with anti-MDA-5 antibodies (aMDA-5) syndromes are near one of the other autoimmune inflammatory myopathies potentially responsible for severe acute interstitial lung disease. We undertook a 13-year retrospective multicenter study in 35 French ICUs in order to describe the clinical presentation and the outcome of patients admitted to the ICU for acute respiratory failure (ARF) revealing AS or aMDA-5 syndromes.

Results

From 2005 to 2017, 47 patients (23 males; median age 60 [1st–3rd quartiles 52–69] years, no comorbidity 85%) were admitted to the ICU for ARF revealing AS (n = 28, 60%) or aMDA-5 (n = 19, 40%) syndromes. Muscular, articular and cutaneous manifestations occurred in 11 patients (23%), 14 (30%) and 20 (43%) patients, respectively. Seventeen of them (36%) had no extra-pulmonary manifestations. C-reactive protein was increased (139 [40–208] mg/L), whereas procalcitonine was not (0.30 [0.12–0.56] ng/mL). Proportion of patients with creatine kinase ≥ 2N was 20% (n = 9/47). Forty-two patients (89%) had ARDS, which was severe in 86%, with a rate of 17% (n = 8/47) of extra-corporeal membrane oxygenation requirement. Proportion of patients who received corticosteroids, cyclophosphamide, rituximab, intravenous immunoglobulins and plasma exchange were 100%, 72%, 15%, 21% and 17%, respectively. ICU and hospital mortality rates were 45% (n = 21/47) and 51% (n = 24/47), respectively. Patients with aMDA-5 dermato-pulmonary syndrome had a higher hospital mortality than those with AS syndrome (n = 16/19, 84% vs. n = 8/28, 29%; p = 0.001).

Conclusions

Intensivists should consider inflammatory myopathies as a cause of ARF of unknown origin. Extra-pulmonary manifestations are commonly lacking. Mortality is high, especially in aMDA-5 dermato-pulmonary syndrome.

Squamous cell carcinoma of the lung associated with anti-Jo1 antisynthetase syndrome: a case report and review of the literature

Antisynthetase syndrome is a heterogeneous idiopathic inflammatory myopathy. Anti-Jo1 is the most common antibody found in this condition. Dermatomyositis is known to be associated with malignancy, but the association between antisynthetase syndrome and malignancy is not clearly established. We report a case of an association of squamous cell carcinoma of the lung and anti-Jo1 antisynthetase syndrome. A 67-year-old man presented with polyarthritis, muscle weakness of the pelvic girdle, "mechanic's hands," and weight loss. A diagnosis of antisynthetase syndrome was considered based on the clinical features and the presence of anti-Jo1 antibodies. Positron emission tomography was performed because of weight loss and revealed a pulmonary hypermetabolic lesion. Histological findings revealed squamous cell carcinoma. The patient underwent lobectomy and is currently free of symptoms with regular monitoring. This unusual presentation of squamous cell carcinoma of the lung illustrates the need of a systematic approach to the diagnosis of antisynthetase syndrome. Positron emission tomography can be a useful imaging modality in the diagnosis of paraneoplastic syndromes associated with antisynthetase syndrome especially in the presence of warning signs/symptoms.

Idiopathic Inflammatory Myopathies and Malignancy: a Comprehensive Review

The idiopathic inflammatory myopathies (IIMs) are a heterogeneous group of autoimmune diseases (collectively known as myositis) affecting the skeletal muscles as well as other organ systems such as skin, lungs, and joints. The primary forms of myositis include polymyositis (PM), dermatomyositis (PM), and immune-mediated necrotizing myopathy (IMNM). Patients with these diseases experience progressive proximal muscle weakness, have characteristic muscle biopsy findings, and produce autoantibodies that are associated with unique clinical features. One distinguishing feature of these patients is that they are also known to have an increased risk of cancer. Since the first description of the association in 1916, it has been extensively reported in the medical literature. However, there have been significant variations between the different studies with regard to the degree of cancer risk in patients with IIM. These discrepancies can, in part, be attributed to differences in the definition of malignancy-associated myositis used in different studies. In recent years, significant advances have been made in defining specific features of IIM that are associated with the development of malignancy. One of these has been myositis-specific antibodies (MSAs), which are linked to distinct clinical phenotypes and categorize patients into groups with more homogeneous features. Indeed, patients with certain MSAs seem to be at particularly increased risk of malignancy. This review attempts a systematic evaluation of research regarding the association between malignancy and myositis.

The Diagnosis and Treatment of Antisynthetase Syndrome

Anti-synthetase syndrome is an autoimmune condition, characterized by antibodies directed against an aminoacycl transfer RNA synthetase along with clinical features that can include interstitial lung disease, myositis, Raynaud's phenomenon, and arthritis. There is a higher prevalence and increased severity of interstitial lung disease in patients with anti-synthetase syndrome, as compared to dermatomyositis and polymyositis, inflammatory myopathies with which it may overlap phenotypically. Diagnosis is made by a multidisciplinary approach, synthesizing rheumatology and pulmonary evaluations, along with serologic, radiographic, and occasionally muscle and/or lung biopsy results. Patients with anti-synthetase syndrome often require multi-modality immunosuppressive therapy in order to control the muscle and/or pulmonary manifestations of their disease. The long-term care of these patients mandates careful attention to the adverse effects and complications of chronic immunosuppressive therapy, as well as disease-related sequelae that can include progressive interstitial lung disease necessitating lung transplantation, pulmonary hypertension, malignancy and decreased survival. It is hoped that greater awareness of the clinical features of this syndrome will allow for earlier diagnosis and appropriate treatment to improve outcomes in patients with anti-synthetase syndrome.

Respiratory failure in a patient with dermatomyositis

Since its original description in 1956 the association between interstitial lung disease and polymyositis (PM) and dermatomyositis (DM) has become well established. Interstitial lung disease (ILD) can be a significant complication in rheumatic diseases (RDs). Although most patients with RD do not develop clinically evident ILD, these systemic autoimmune disorders are estimated to be responsible for approximately 25% of all ILD deaths and 2% of deaths due to all respiratory causes. Radiologic abnormalities in DM are characterized by a high incidence of airspace consolidation. Non-Specific Interstitial Pneumonia (NSIP) is the most common form of lung disease, with a frequency in biopsies 4-fold greater than that of Usual Interstitial Pneumonia (UIP) in PM and a slightly smaller predominance in DM.

We report a case of a female patient, 57 years old, no former smoker, whose clinical history was onset in November 2008 with asthenia with muscle and osteoarticular pain especially located in the upper limbs and then also expanded to the lower limbs. The EMG was compatible with dermatomyositis in the acute phase. The patient received therapy with steroids and tacrolimus, also making several rounds of treatment with immunoglobulin. Given the recurrence of myositis in association with signs of poorly controlled interstitial lung disease, immunosuppressive therapy with Rituximab was administered. The Computed Tomography (CT) scans showed "bronchiectasis and traction bronchiolectasis, hypodense areas consistent with the phenomena of air trapping. The pattern of interstitial lung disease with fibrotic evolution seems consistent with NSIP.

The arterial blood gas analysis showed a pattern of hypoxic-hypercapnic respiratory failure (pH: 7,34, PaO₂: 67 mmHg; PaCO₂: 55 mmHg).

As a result of an episode of marked desaturation unresponsive to supplemental oxygen at high flows we proceeded to noninvasive mechanical ventilation with Helmet for 24 hours/24. This ventilatory support was maintained for a week, with resolution of the respiratory failure.

In this brief case report we want to highlight various pulmonary complications as a result of dermatomyositis. The progression of respiratory complications may also lead to a situation of respiratory failure, as in our patient, and require a noninvasive ventilatory treatment.

Pleuropulmonary pathology in patients with rheumatic disease

Thoracic manifestations of rheumatic disease (RD) are increasingly recognized as a significant cause of morbidity and mortality worldwide. Rheumatologic underpinnings have been identified in a significant proportion of patients with interstitial lung disease. The 5 RDs most frequently associated with pleuropulmonary disease are (1) rheumatoid arthritis, (2) systemic lupus erythematosus, (3) progressive systemic sclerosis, (4) polymyositis/dermatomyositis, and (5) Sjögren syndrome. The onset of thoracic involvement in these diseases is variable. In some patients, it precedes the systemic disease or is its only manifestation. Moreover, there is a wide spectrum of clinical presentation ranging from subclinical abnormalities to acute respiratory failure. Histopathologically, the hallmark features of thoracic involvement by RD are inflammatory, targeting one or more lung compartments. The reactions range from acute to chronic, with remodeling by fibrosis being a common result. Although the inflammatory findings are often nonspecific, certain reactions or anatomic distributions may favor one RD over another, and occasionally, a distinctive histopathology may be present (eg, rheumatoid nodules). Three diagnostic dilemmas are encountered in patients with RD who develop diffuse lung disease: 1) opportunistic infection in the immunocompromised host, 2) drug toxicity related to the medications used to treat the systemic disease, and 3) manifestations of the patient's known systemic disease in lung and pleura. To confidently address the latter, the 5 major RDs are presented here, with their most common pleuropulmonary pathologic manifestations, accompanied by brief clinical and radiologic correlations.