Interstitial pneumonitis in association with polymyositis and dermatomyositis

Myositis interstitial lung disease and autoantibodies

The aim of this review is to examine and evaluate published literature associated with idiopathic inflammatory myopathies (IIM) and interstitial lung disease (ILD) based on myositis specific autoantibodies (MSA) and the potential clinical significance of each autoantibody subtype for the practicing clinician. The review is a comprehensive search of literature published in PubMed from the year 2005 and onward coinciding with the surge in the discovery of new MSAs. Additionally, we comment on recommended multidisciplinary longitudinal care practices for patients with IIM-ILD with regard to imaging and other testing. Treatment is not covered in this review.

Myositis Antibodies and Interstitial Lung Disease

BACKGROUND

Interstitial lung disease (ILD) comprises a heterogeneous group of inflammatory and fibrotic conditions, often resulting in progressive lung function decline and increased mortality. Connective tissue disease (CTD) should be considered in all patients with ILD, as distinguishing between CTD-ILD and other forms of fibrotic lung disease has important therapeutic and prognostic implications. The idiopathic inflammatory myopathies (IIM) represent a CTD subtype of growing interest to ILD experts. The expansion and availability of myositis-specific and myositis-associated antibody testing has allowed for improved disease detection and characterization.

CONTENT

In this review, we highlight the relationship between myositis antibodies and ILD. Select forms of IIM, such as the antisynthetase syndrome and clinically amyopathic dermatomyositis can present with rapidly progressive ILD, warranting timely disease diagnosis and management. Disease phenotypes, prevalence, laboratory testing, prognosis, and management strategies are described according to select myositis antibodies.

SUMMARY

Myositis antibodies provide valuable information for clinicians managing patients with ILD. This review aims to increase awareness of their role in disease detection, pathophysiology, and possibly therapeutics.

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.

2020 guide for the diagnosis and treatment of interstitial lung disease associated with connective tissue disease

The prognosis of patients with connective tissue disease (CTD) has improved significantly in recent years, but interstitial lung disease (ILD) associated with connective tissue disease (CTD-ILD) remains a refractory condition, which is a leading cause of mortality. Because it is an important prognostic factor, many observational and interventional studies have been conducted to date. However, CTD is a heterogeneous group of conditions, which makes the clinical course, treatment responses, and prognosis of CTD-ILD extremely diverse. To summarize the current understanding and unsolved questions, the Japanese Respiratory Society and the Japan College of Rheumatology collaborated to publish the world's first guide focusing on CTD-ILD, based on the evidence and expert consensus of pulmonologists and rheumatologists, along with radiologists, pathologists, and dermatologists. The task force members proposed a total of 27 items, including 7 for general topics, 9 for disease-specific topics, 3 for complications, 4 for pharmacologic treatments, and 4 for non-pharmacologic therapies, with teams of 2-4 authors and reviewers for each item to prepare a consensus statement based on a systematic literature review. Subsequently, public opinions were collected from members of both societies, and a critical review was conducted by external reviewers. Finally, the task force finalized the guide upon discussion and consensus generation. This guide is expected to contribute to the standardization of CTD-ILD medical care and is also useful as a tool for promoting future research by clarifying unresolved issues.

Chest computed tomography findings of adult patients with antimelanoma differentiation-associated protein 5 antibody-positive interstitial lung disease

OBJECTIVES

Interstitial lung disease (ILD) associated with the antimelanoma differentiation-associated protein 5 (anti-MDA5) antibody is a rapidly progressive disease that requires timely, aggressive treatment. However, prompt diagnosis is difficult due to the longer time required for antibody detection. This study described the computed tomography (CT) findings of anti-MDA5 antibody-positive ILD (anti-MDA5-ILD).

METHODS

CT findings of 20 patients (7 men, 13 women; mean age, 53.6 ± 13.5 years) with anti-MDA5-ILD were retrospectively reviewed. All patients had clinical diagnoses of dermatomyositis, and 14 patients presented with amyopathic findings.

RESULTS

Bilateral ground-glass attenuation, air-space consolidation, and reticular shadows were observed in 20 (100%), 15 (75%), and 3 (15%) patients, respectively. The spread of air-space consolidation was 6.0 ± 5.6% (mean ± standard deviation). Univariate analysis revealed that high Krebs von den Lungen-6, high spread of consolidation, low partial pressure of oxygen, and low forced vital capacity were significant predictors for poor survival. The final radiological diagnoses were nonspecific interstitial pneumonia and organising pneumonia (OP) in 2 (10%) and 16 (80%) patients, respectively. Further, 30% of OP patients showed fibrosis.

CONCLUSION

The characteristic CT findings of patients with anti-MDA5-ILD were ground-glass attenuation, air-space consolidation, and less reticulation. These CT findings were compatible with those of OP.

Management of Myositis-Associated Interstitial Lung Disease

Idiopathic inflammatory myopathies, including polymyositis (PM), dermatomyositis (DM), and clinically amyopathic DM (CADM), are a diverse group of autoimmune diseases characterized by muscular involvement and extramuscular manifestations. Interstitial lung disease (ILD) has major pulmonary involvement and is associated with increased mortality in PM/DM/CADM. The management of PM-/DM-/CADM-associated ILD (PM/DM/CADM-ILD) requires careful evaluation of the disease severity and clinical subtype, including the ILD forms (acute/subacute or chronic), because of the substantial heterogeneity of their clinical courses. Recent studies have highlighted the importance of myositis-specific autoantibodies’ status, especially anti-melanoma differentiation-associated gene 5 (MDA5) and anti-aminoacyl tRNA synthetase (ARS) antibodies, in order to evaluate the clinical phenotypes and treatment of choice for PM/DM/CADM-ILD. Because the presence of the anti-MDA5 antibody is a strong predictor of a worse prognosis, combination treatment with glucocorticoids (GCs) and calcineurin inhibitors (CNIs; tacrolimus (TAC) or cyclosporin A (CsA)) is recommended for patients with anti-MDA5 antibody-positive DM/CADM-ILD. Rapidly progressive DM/CADM-ILD with the anti-MDA5 antibody is the most intractable condition, which requires immediate combined immunosuppressive therapy with GCs, CNIs, and intravenous cyclophosphamide. Additional salvage therapies (rituximab, tofacitinib, and plasma exchange) should be considered for patients with refractory ILD. Patients with anti-ARS antibody-positive ILD respond better to GC treatment, but with frequent recurrence; thus, GCs plus immunosuppressants (TAC, CsA, azathioprine, and mycophenolate mofetil) are often needed in order to achieve favorable long-term disease control. PM/DM/CADM-ILD management is still a therapeutic challenge for clinicians, as evidence-based guidelines do not exist to help with management decisions. A few prospective clinical trials have been recently reported regarding the treatment of PM/DM/CADM-ILD. Here, the current knowledge on the pharmacologic managements of PM/DM/CADM-ILD was mainly reviewed.

Recognition and Management of Myositis-Associated Rapidly Progressive Interstitial Lung Disease

Idiopathic inflammatory myopathies are autoimmune processes that are characterized by skeletal muscle inflammation. The lung is the most commonly involved extramuscular organ, and, when present, pulmonary disease drives morbidity and mortality. A subset of patients can present with rapidly progressive hypoxemic respiratory failure due to myositis-related interstitial lung disease. Confirmatory autoantibody testing requires sending samples to a reference laboratory; thus, diagnosis of rapidly progressive myositis-associated interstitial lung disease relies on a high index of suspicion and careful history and physical examination. Although the cornerstone of therapy for these patients remains multimodality immunosuppression, emerging data support a role for advanced therapies (including extracorporeal membrane oxygenation and lung transplantation) in appropriately selected patients. It is hoped that greater awareness of the clinical features of this syndrome will allow for appropriate diagnosis and treatment of these potentially treatable patients, as well as raise awareness of the need for multicenter collaboration to prospectively study how to manage this complex disease.

Therapeutic Options for the Treatment of Interstitial Lung Disease Related to Connective Tissue Diseases. A Narrative Review

Interstitial lung disease (ILD) is one of the most serious pulmonary complications of connective tissue diseases (CTDs) and it is characterized by a deep impact on morbidity and mortality. Due to the poor knowledge of CTD-ILD’s natural history and due to the difficulties related to design of randomized control trials, there is a lack of prospective data about the prevalence, follow-up, and therapeutic efficacy. For these reasons, the choice of therapy for CTD-ILD is currently very challenging and still largely based on experts’ opinion. Treatment is often based on steroids and conventional immunosuppressive drugs, but the recent publication of the encouraging results of the INBUILD trial has highlighted a possible effective and safe use of antifibrotic drugs as a new therapeutic option for these subjects. Aim of this review is to summarize the available data and recent advances about therapeutic strategies for ILD in the context of various CTD, such as systemic sclerosis, idiopathic inflammatory myopathy and Sjogren syndrome, systemic lupus erythematosus, mixed connective tissue disease and undifferentiated connective tissue disease, and interstitial pneumonia with autoimmune features, focusing also on ongoing clinical trials.

Recent Treatment of Interstitial Lung Disease with Idiopathic Inflammatory Myopathies

Interstitial lung disease (ILD) is a prognostic factor for poor outcome in polymyositis (PM)/dermatomyositis (DM). The appropriate management of ILD is very important to improve the prognosis of patients with PM/DM. ILD activity and severity depend on the disease subtype. Therefore, clinicians should determine therapeutic strategies according to the disease subtype in each patient with PM/DM. Anti-melanoma differentiation-associated gene 5 antibody and hyperferritinemia predict the development and severity of rapidly progressive (RP) ILD, particularly in East Asian patients. Combination therapy with corticosteroids, intravenous cyclophosphamide pulse, and calcineurin inhibitors should be administered in RP-ILD. In contrast, patients with anti-aminoacyl-tRNA synthetase (ARS) show better responses to corticosteroids alone. However, ILDs with anti-ARS often display disease recurrence or become refractory to corticosteroid monotherapy. Recent studies have demonstrated that the administration of tacrolimus or rituximab in addition to corticosteroids may be considered in ILD patients with anti-ARS. Large-scale, multicenter randomized clinical trials should be conducted in the future to confirm that the aforementioned agents exhibit efficacy in ILD patients with PM/DM. The pathophysiology of ILD with PM/DM should also be elucidated in greater detail to develop effective therapeutic strategies for patients with ILD in PM/DM.

Interstitial lung disease in inflammatory myopathies: clinical phenotypes and prognosis

Interstitial lung disease (ILD) is a very important complication of the idiopathic inflammatory myositides (IIM), with a prevalence of approximately 40 %. Characteristic HRCT changes, most commonly NSIP, together with a restrictive ventilatory defect and an associated decline in DLco support the presence of ILD. The strongest risk factors are the presence of the anti-amino-acyl-tRNA synthetases (ARS) and anti-MDA-5 antibodies, but a raised index of suspicion for ILD should also apply to IIM patients of black ethnicity. Overall, the prognosis of ILD in IIM is good; between 50 and 66 % of cases have a stable disease course over a substantial period of time. The remaining proportion will show signs of worsening lung disease within 12 months of diagnosis. Whereas ARS antibodies and black ethnicity have no influence on ILD prognosis, detection of the anti-MDA-5 antibody carries a poor ILD outcome, in which hyperferritinaemia appears to be an important diagnostic and prognostic feature.

Interstitial lung disease in the connective tissue diseases

The connective tissue diseases (CTDs) are inflammatory, immune-mediated disorders in which interstitial lung disease (ILD) is common and clinically important. Interstitial lung disease may be the first manifestation of a CTD in a previously healthy patient. CTD-associated ILD frequently presents with the gradual onset of cough and dyspnea, although rarely may present with fulminant respiratory failure. Infection and drug reaction should always be ruled out. A diagnosis of idiopathic ILD should never be made without a careful search for subtle evidence of underlying CTD. Treatment of CTD-ILD typically includes corticosteroids and immunosuppressive agents.

KL-6: a serological biomarker for interstitial lung disease in patients with polymyositis and dermatomyositis

OBJECTIVES

To investigate whether Caucasian patients with polymyositis (PM) or dermatomyositis (DM) and interstitial lung disease (ILD) have elevated serum levels of KL-6 compared with patients without ILD and whether KL-6 could be used as a marker for ILD activity and treatment efficacy of ILD in PM/DM.

DESIGN AND METHODS

Thirty patients with PM/DM (seven with ILD) and 17 age- and sex-matched healthy controls were included in a retrospective, cross-sectional analysis. Twelve patients were followed for longitudinal evaluation. ILD was defined as restrictive lung function impairment with radiographic signs of ILD. Serum KL-6 levels were measured using a sandwich enzyme immunoassay kit. Groups were compared by Mann-Whitney U-test.

RESULTS

PM/DM patients with ILD had significantly higher median serum KL-6 levels compared with those without ILD: 995 (range 533-2318) versus 322 (range 132-1225) U mL(-1) (P = 0.0002). Median serum levels of healthy controls were 225 (range 136-519) U mL(-1) . Serum levels of KL-6 were inversely correlated with percentages of forced expiratory volume in 1 s (FEV1), vital capacity (VC), total lung capacity (TLC), forced VC, diffusing capacity of carbon monoxide (DLco), maximal voluntary ventilation at 40 breaths min(-1) and residual volume (RV). Changes in KL-6 levels showed a significant inverse correlation with changes in percentage FEV1, TLC, DLco and RV. At a cut-off level of 549 U mL(-1) (mean ± 2.5 SD for controls), the sensitivity and specificity for diagnosis of ILD were 83% and 100%, respectively.

CONCLUSION

The level of serum KL-6 may serve as measure of ILD in patients with PM/DM and is a promising biomarker for use in clinical practice to assess clinical response to treatment.

Myositis-related interstitial lung disease and antisynthetase syndrome

In patients with myositis, the lung is commonly involved, and the presence of anti-aminoacyl-tRNA synthetase (anti-ARS) antibodies marks the presence or predicts the development of interstitial lung disease (ILD). A distinct clinical entity-antisynthetase syndrome-is characterized by the presence of anti-ARS antibodies, myositis, ILD, fever, arthritis, Raynaud's phenomenon, and mechanic's hands. The most common anti-ARS antibody is anti-Jo-1. More recently described anti-ARS antibodies might confer a phenotype that is distinct from that of anti-Jo-1-positive patients and is characterized by a lower incidence of myositis and a higher incidence of ILD. Among patients with antisynthetase syndrome-related ILD, the response to immunosuppressive medications is generally, but not universally, favorable.

Polymyositis, dermatomyositis, and autoimmune necrotizing myopathy: clinical features

Idiopathic inflammatory myopathies are a heterogeneous group of autoimmune disorders predominantly affecting skeletal muscles, resulting in muscle inflammation and weakness. The 3 most common inflammatory myopathies are polymyositis (PM), dermatomyositis (DM), and inclusion body myositis. This review details the clinical findings noted in PM, DM, and the emerging entity of autoimmune necrotizing myopathy.

The lung as a possible target for the immune reaction in myositis

Interstitial lung disease is a common manifestation of autoimmune myositis that confers significant morbidity and mortality. The vulnerability of the lung may offer insight into the etiology of this autoimmune disease. The frequency and patterns of lung injury vary based on the autoantibody. Antibodies against the aminoacyl-tRNA synthetases and melanoma differentiation-induced gene-5 are frequently associated with interstitial lung disease. Although the mechanisms underlying these associations have not been fully elucidated, emerging data highlight the importance of autoantigen expression and conformation in the target tissue (lung and muscle, in this case), as well as identifying relevant amplifying pathways (such as regeneration).

Autoimmune myopathies: autoantibodies, phenotypes and pathogenesis

The different autoimmune myopathies-for example, dermatomyositis, polymyositis, and immune-mediated necrotizing myopathies (IMNM)-have unique muscle biopsy findings, but they also share specific clinical features, such as proximal muscle weakness and elevated serum levels of muscle enzymes. Furthermore, around 60% of patients with autoimmune myopathy have been shown to have a myositis-specific autoantibody, each of which is associated with a distinct clinical phenotype. The typical clinical presentations of the autoimmune myopathies are reviewed here, and the different myositis-specific autoantibodies, including the anti-synthetase antibodies, dermatomyositis-associated antibodies, and IMNM-associated antibodies, are discussed in detail. This Review also focuses on a newly recognized form of IMNM that is associated with statin use and the production of autoantibodies that recognize 3-hydroxy-3-methylglutaryl-coenzyme A reductase, the pharmacological target of statins. The contribution of interferon signaling to the development of dermatomyositis and the potential link between malignancies and the initiation of autoimmune myopathies are also assessed.

Interstitial lung disease associated with the idiopathic inflammatory myopathies: what progress has been made in the past 35 years?

Interstitial lung disease is commonly associated with the autoimmune inflammatory myopathies dermatomyositis and polymyositis and accounts for significant morbidity and mortality in these conditions. In the 35 years since the association between inflammatory myopathy and interstitial lung disease was initially described, there has been progress in diagnosing and treating this dis-order. Nevertheless, there remains much about pathogenesis and therapeutics to be learned. This review examines the changes in the understanding of this complex condition, highlighting recent advances and areas deserving of further study.

Polymyositis/dermatomyositis and interstitial lung disease: A new therapeutic approach with T-cell-specific immunosuppressants

Interstitial lung disease (ILD) is a common complication of polymyositis (PM) and dermatomyositis (DM), and accounts for a significant proportion of their morbidity and mortality because of the resistance to therapeutic agents including corticosteroids. Its pathogenic mechanism is not known, but several studies have provided findings implicating that T-cells, especially activated CD8+ cells, may play essential roles, and thus could be therapeutic targets in this disease. To test this hypothesis, we began clinical investigation of the efficacy of T-cell-specific immunosuppressants, cyclosporine (CsA) and FK506, in PM/DM patients with ILD. In our retrospective nationwide multi-center study compiling a total of 53 patients, a combination of CsA and corticosteroids resulted in favorable early and long-term outcome in the majority of patients except for DM patients with acute ILD. In this subset, those who received the combination as an initial therapy had better survival than those who initially received corticosteroids alone. FK506 has a similar mode of action but is up to 100-fold more potent than CsA in vitro, and has been used in more refractory ILD cases. We next reviewed 5 PM/DM patients with ILD who failed on various immunosuppressants including CsA and were subsequently treated with FK506 in our hospital, and found that 3 improved promptly, 1 gradually and steadily, and another case responded slowly after prednisolone dose was increased. None developed adverse effects. In summary, these T-cell targeted therapies have a potential to be the cornerstone of the treatment for ILD in PM/DM patients. The combination therapy with CsA and corticosteroids may be efficacious especially when used early. FK506 may be advantageous even in refractory cases to CsA. These findings indicate that further investigation is warranted. Currently, prospective investigation of FK506 is underway.

Anti-synthetase syndrome in ANA and anti-Jo-1 negative patients presenting with idiopathic interstitial pneumonia

OBJECTIVES

To describe the clinical features of patients presenting with "idiopathic" interstitial pneumonia that were diagnosed with anti-synthetase syndrome based on clinical features and positive anti-PL-7 or PL-12 antibodies.

METHODS

Over a 24-month period, we evaluated 37 patients who presented with clinical features of anti-synthetase (AS) syndrome, negative anti-Jo-1 antibodies, and who were assessed for other anti-tRNA synthetase (anti-tRS) antibodies. All data were abstracted from the medical record.

RESULTS

Nine (24%) were confirmed to have non-anti-Jo-1 positive AS syndrome based on clinical features and the presence of other anti-tRS antibodies (seven with anti-PL-7, two with anti-PL-12 antibodies). All presented with dyspnea as the initial symptom and with ILD as the first manifestation. Elevated CPK was identified in three patients but only two had muscle weakness. Pulmonary physiology revealed restriction (forced vital capacity 60% of predicted) and impaired gas transfer (diffusing capacity for carbon monoxide 40% of predicted). All had similar findings on thoracic HRCT scans, with basilar predominance of abnormalities and patterns suggestive of non-specific interstitial pneumonia and organizing pneumonia. Immunomodulatory therapies were used to treat the ILD-responses were variable, but some subjects clearly improved.

CONCLUSION

Anti-PL-7 and PL-12 antibodies may be more common among patients presenting with "idiopathic" interstitial pneumonia than formerly considered and should be checked in patients with features of AS syndrome despite a negative screen for anti-nuclear or anti-Jo-1 antibodies. Further research is needed to advance understanding of anti-PL-7 or anti-PL-12-positive AS syndrome, including its prognosis and optimal approaches to therapy.

Interstitial lung disease in polymyositis and dermatomyositis

The aim of the study was to estimate the prevalence, characteristics, and prognostic factors of interstitial lung disease (ILD) in patients with polymyositis (PM) and dermatomyositis (DM). The medical records of 151 PM/DM patients treated at Chang Gung Memorial Hospital between January, 2000 and June, 2007 were retrospectively reviewed. Thirty of 151 (19.9%) PM/DM patients had developed ILD. Older age at PM/DM onset, anti-Jo-1 antibody, and arthritis/arthralgia were associated with the presence of ILD (p = 0.004, p = 0.008, and p = 0.026, respectively). Anti-Jo-1 was initially excluded from the multivariate analysis because only 80 patients underwent the test. An older age at onset above 45 years (odds ratio 3.28, 95% confidence interval (CI) 1.15-9.34, p = 0.026) and arthritis/arthralgia at onset (odds ratio (OR) 2.57, 95% CI 1.09-6.08, p = 0.032) were the two independent risk factors for developing ILD. If anti-Jo-1 was included in the multivariate analysis (n = 80), then an older age at onset above 45 years (OR 7.30, 95% CI 1.70-31.40, p = 0.008) and anti-Jo-1 positive (OR 7.89, 95% CI 1.18-52.87, p = 0.033) were associated with ILD, while arthritis/arthralgia was no longer significant (OR 2.64, 95% CI 0.70-10.01, p = 0.153). Of the 30 ILD patients, 16 (53.3%) died. The survival time was significantly shorter in ILD patients than in patients without ILD (p < 0.001). Poor survival in ILD patients was associated with male gender (p = 0.039), a Hamman-Rich-like presentation (p = 0.039), and a clinical diagnosis of acute interstitial pneumonia (p = 0.007).

A patient with antihistidyl-tRNA synthetase positive polymyositis presenting as acute respiratory distress syndrome

We describe an unusual case of a 48-year-old white woman diagnosed with positive antihistidyl-trna synthetase antibody polymyositis (PM) shortly after suffering from life-threatening acute respiratory distress syndrome (ARDS). In view of the fact that evaluation for infectious or noninfectious etiologies of ARDS was unrevealing, we reasoned that systemic inflammation in early subclinical PM may have precipitated alveolar-capillary membrane injury. One year after onset, PM has been maintained in remission with oral prednisone and azathioprine. This is the first report of a patient in whom ARDS was the presenting feature of anti-Jo-1 positive PM.

Ascertainment of collagen vascular disease in patients presenting with interstitial lung disease

INTRODUCTION

Previous studies of interstitial lung disease (ILD) suggest that prognosis and therapeutic response are influenced by the presence of underlying collagen vascular disease (CVD). Yet, what proportion of patients presenting with ILD have CVD is largely unknown. We sought to determine the frequency of a new CVD diagnosis in an ILD referral population.

MATERIALS/PATIENTS AND METHODS

We retrospectively studied 114 consecutive patients evaluated at the Johns Hopkins Interstitial Lung Disease Clinic for the development of CVD.

RESULTS

In this retrospective cohort, nearly one-third of the 114 patients with confirmed ILD satisfied published criteria for a CVD diagnosis. Seventeen (15%) patients were diagnosed with a new CVD as a direct consequence of their ILD evaluation. Patients with new CVD diagnosis were younger than those without new CVD diagnosis: 51.4years (95% CI 45-58years) and 60years (95% CI 57-63), respectively (p=0.01). Moreover, an ANA>or=1:640 (p=0.03) and elevated levels of creatine phosphokinase (CPK) or aldolase (p<0.001) were associated with a new CVD diagnosis.

CONCLUSIONS

Unrecognized collagen vascular disease may be more common than previously appreciated among patients referred with ILD. High titer ANA and an elevated CPK or aldolase are associated with a CVD diagnosis in this referral population.

Atteintes pulmonaires des polymyosites et dermatopolymyosites

Polymyositis is characterised by an inflammatory reaction in skeletal muscle with a variable degree of muscular weakness and associated with skin lesions in the case of dermatomyositis. Involvement of the muscles of deglutition and the diaphragm may lead to inhalation pneumonia and acute or chronic respiratory failure, often hypercapnic. The other respiratory manifestations are diffuse interstitial pneumonitis (DIP), usually non-specific, and very occasionally pulmonary arterial hypertension. The development of DIP during polymyositis is a grave prognostic factor, respiratory involvement being one of the main causes of morbidity and mortality. The onset of DIP is acute in between 30 and 47% of cases. Anti-synthetase antibodies (particularly anti-JO-1) are positive in about 75% of cases. Treatment is usually with a combination of immunosuppressants and corticosteroids without any immunosuppressants therapy having shown a superiority.

A case of polymyositis complicated with interstitial pneumonitis and pneumomediastinum

Pneumomediastinum as a complication of interstitial pneumonia with leakage of air into the mediastinum or subcutaneous tissues is a rare complication of dermatomyositis (DM). Herein we report a case of pneumomediastinum complicating polymyositis (PM), which is usually associated with DM. A 61-year-old man was hospitalized in our department because of deterioration of interstitial pneumonia. Treatment with high-dose corticosteroid and cyclosporin A steadily improved his interstitial pneumonia. Two weeks later, he developed subcutaneous emphysema and chest X-ray showed pneumomediastinum. Both subcutaneous emphysema and pneumomediastinum improved gradually without any additional treatment.

Atteinte pulmonaire au cours des polymyosites et des dermatomyosites

Interstitial lung disease is a serious complication of polymyositis/dermatomyositis and leads to death from chronic respiratory insufficiency in 30 to 66% of cases. It is a criterion of poor prognosis in these disorders. Its onset occurs at variable points in the course of polymyositis/dermatomyositis, and precedes them in half of all cases. Presentation may also vary: acute (25%), insidious (60%), or infraclinical, discovered fortuitously (15%). The examinations of choice for early screening are high-resolution computed tomography (CT) and pulmonary function tests, which should be performed during the initial work-up and during ongoing surveillance. Moreover, high-resolution CT also makes it possible to determine the type of histologic lesions in the interstitial lung disease. Today, diagnosis of this disease does not generally require histological confirmation; nonspecific interstitial lung disease seems to be the most common histologic form of lung damage in polymyositis/dermatomyositis (40 to 80%). Anti-Jo1 antibodies are a sensitive marker of interstitial lung disease during polymyositis/dermatomyositis, and close surveillance of lung function is recommended in patients with these autoantibodies. Systematic testing for them is also justified in patients with apparently idiopathic interstitial lung disease, to rule out underlying polymyositis/dermatomyositis. No clear treatment protocols have been established for interstitial lung disease during polymyositis/dermatomyositis. Corticosteroid treatment is the first choice. Its combination with cyclophosphamide may be most effective in corticosteroid-resistant forms of polymyositis/dermatomyositis, especially when begun early; it may also be appropriate to begin corticosteroids as soon as factors predicting poor prognosis are detected.

A systematic review of adult-onset clinically amyopathic dermatomyositis (dermatomyositis siné myositis): a missing link within the spectrum of the idiopathic inflammatory myopathies

OBJECTIVE

Classical dermatomyositis (CDM) patients display the hallmark cutaneous manifestations of dermatomyositis (DM), proximal muscle weakness, and laboratory evidence of myositis. The epidemiology and management of both adult-onset and juvenile-onset CDM has been well characterized. However, the clinical significance of the hallmark inflammatory cutaneous manifestations of DM occurring in individuals who have no clinically significant muscle weakness and normal muscle enzymes for prolonged periods of time (ie, 6 months or longer) has not been clear. The term amyopathic DM (ADM) (synonymous with DM siné myositis) has been proposed to draw attention to such individuals. A related form of DM, "hypomyopathic DM" [HDM], is the presence of DM skin disease for 6 months or longer in individuals who have no muscle weakness but who are found to have some evidence of muscle inflammation upon testing (muscle enzyme levels, electromyogram, muscle biopsy, muscle magnetic resonance imaging [MRI]). Clinically amyopathic DM (CADM) is a designation that has been proposed for patients having either ADM or HDM. The clinically amyopathic component of this designation was coined to emphasize the fact that the only clinical problem being experienced by these patients at the time of diagnosis is their DM skin disease. Our personal experience suggests that the CADM subphenotype might be more prevalent in adults than has been thought previously. To test this hypothesis and address questions relating to the optimal management and prognosis of such patients, we have systematically reviewed the published literature in this area.

METHODS

We carried out a systematic review of the published literature on adult-onset CADM as defined in Table 1 through May 1, 2004.

RESULTS

We identified 291 adult-onset CADM cases (18 years or older) reported from over 19 countries. The average duration of DM skin disease was 3.74 years (range, 6 months [by definition] to > 20 years), and 73% were female. Among 37 patients with HDM who were identified, the average duration of disease was 5.4 years, and none had developed clinically significant weakness at the time of the reports. Thirty-seven of the reported CADM patients developed muscle weakness greater than 6 months after onset of their skin disease (15 months to 6 years). For the sake of this discussion, such patients have been analyzed under the designation of "CADM --> CDM." Somewhat surprisingly, 36/291 (13%) of the identified published CADM patients developed interstitial lung disease. Incidental to our review, we also identified 10 published cases of individuals having DM skin disease and interstitial lung disease without muscle weakness, 7 of whom died from interstitial lung disease less than 6 months after onset of their DM skin disease (the term pre-myopathic DM coined by others has been used here to refer to such patients). In addition, an associated internal malignancy was found in 41/291 (14%) of the identified CADM cases. A positive antinuclear antibody was reported in 63% and myositis-specific autoantibodies (eg, Jo-1, Mi-2) in only 3.5% of the reported CADM patients in which such data were available.

CONCLUSIONS

The results of this analysis suggests that the CADM subphenotype is more common than has been thought previously and that such patients may comprise a relatively high proportion of DM patients followed by dermatologists. Some CADM patients also have been observed to develop overt proximal muscle weakness years after onset of their DM skin disease. In addition, CADM patients appear to be at risk of developing the same potentially fatal disease associations/complications for which CDM patients are at risk (eg, interstitial lung disease and internal malignancy). Population-based studies of the epidemiology and optimal management of CADM patients, including efforts to identify risk factors associated with potentially fatal outcomes such as late-onset muscle weakness, interstitial lung disease, and malignancy, are needed. As an incidental finding to this literature review, we also identified a small number of reported cases of often-fatal interstitial lung disease occurring shortly after the onset of DM skin disease (< 6 months) in the complete absence of muscle weakness. This subphenotype, referred to as "pre-myopathic DM," is one with which dermatologists should be aware as early diagnosis and aggressive management can be lifesaving.

Interstitial lung disease in polymyositis and dermatomyositis

PURPOSE OF REVIEW

The purpose of this review is to discuss current concepts regarding management of interstitial lung disease in polymyositis and dermatomyositis.

RECENT FINDINGS

Interstitial lung disease seems to be a more frequent manifestation in patients with polymyositis and dermatomyositis than previously reported. Modern technology, including high-resolution computerized tomography in combination with pulmonary function tests provides sensitive tools to detect early signs of interstitial lung disease. By systematic use of these investigations in newly diagnosed polymyositis and dermatomyositis, up to two thirds of patients were discovered to have signs of interstitial lung disease in a recent study. Clinical symptoms such as cough and dyspnea may not be sensitive enough to detect interstitial lung disease. Awareness of this complication in patients with myositis is important, because early diagnosis and management of interstitial lung disease may prevent development of chronic pulmonary fibrosis and thereby prolong patient survival and improve quality of life. Treatment recommendations of interstitial lung disease in polymyositis and dermatomyositis are still limited by absence of controlled trials and could only be based on experiences from small case series and case reports. At least some patients with interstitial lung disease improve with immunosuppressive treatment, but data are limited, and longitudinal studies are needed.

SUMMARY

Interstitial lung disease seems to be a common manifestation in patients with polymyositis and dermatomyositis already at diagnosis of the muscle disease. When present, interstitial lung disease has a major effect on morbidity and mortality and should be looked for in these patients using high-resolution computerized tomography and pulmonary function tests early in the disease course, because immunosuppressive treatment may change the course of the lung disease.

Interstitial lung disease, a common manifestation of newly diagnosed polymyositis and dermatomyositis

OBJECTIVES

To estimate the prevalence and predictors of interstitial lung disease in newly diagnosed polymyositis and dermatomyositis.

METHODS

A prospective study in which consecutive patients with newly diagnosed poly- and dermatomyositis, regardless of clinical symptoms of pulmonary disease, were investigated with chest x ray, high resolution computed tomography (HRCT), pulmonary function tests, and biochemical and autoantibody analysis. Patients with inclusion body myositis, malignancy, other defined inflammatory connective tissue diseases (CTDs), or antibody profile indicating other CTDs were excluded.

RESULTS

Between March 1998 and September 2000, 26 new cases of poly- or dermatomyositis were diagnosed; 17 of those patients were included in the study. Interstitial lung disease (ILD), defined as radiological signs on chest x ray examination/HRCT or restrictive ventilatory defect, were found in 11 (65%) patients and were more common in men than in women. Arthritis and occurrence of anti-Jo-1 antibodies were found more often in patients with ILD than in those without. There was no statistically significant association between respiratory symptoms, other serological or laboratory variables and ILD.

CONCLUSIONS

ILD is a common early manifestation in patients with poly- and dermatomyositis and is not always related to clinical symptoms. Chest x ray examination, HRCT, pulmonary function tests, and analysis of anti-Jo-1 antibodies should be included in the initial investigation of patients with myositis regardless of respiratory symptoms.

Myopathies

Electrodiagnostic studies are an important adjunct to the clinical examination of a patient with a suspected myopathy; however, the clinical examination is crucial in making an accurate diagnosis, because electrodiagnostic studies have only a limited role in delineating with certainty the underlying myopathic disorder. Hereditary and acquired myopathies are reviewed in this article, with particular emphasis on distinguishing clinical and electrodiagnostic features. The hereditary myopathies that are discussed include the muscular dystrophies and the congenital distal mitochondrial, and metabolic myopathies. Acquired myopathies, including inflammatory, endocrine, and toxic myopathies, as well as those associated with systemic illness, are briefly reviewed.

Nonspecific interstitial pneumonia associated with polymyositis and dermatomyositis: serial high-resolution CT findings and functional correlation

STUDY OBJECTIVES

We described the features seen on serial high-resolution CT scans of nonspecific interstitial pneumonia (NSIP) that was associated with polymyositis (PM) and dermatomyositis (DM), and we correlated the changes in the CT scan findings with those of pulmonary function test results.

DESIGN, SETTING AND PATIENTS

Serial CT scans of 14 patients with histologically proven NSIP and PM/DM from two university hospitals were evaluated retrospectively (follow-up period, 3 to 61 months; mean follow-up period, 27.6 months). Using initial and follow-up CT scan findings, the extent of each type of opacity and the total area of increased opacity were calculated and correlated with the results of pulmonary function tests.

MEASUREMENTS AND RESULTS

The predominant findings on the initial CT scans were of reticular and/or ground-glass opacities with or without consolidation. Reticular and ground-glass opacities predominated in the lower zone of each lung, and consolidation predominated at the lung periphery. Thirteen patients showed significant improvement of the total area of increased opacity (p < 0.05), and this decrease in extent inversely correlated with changes in FVC (r = -0.650; p = 0.031). Ground-glass and reticular opacities also were improved significantly in 11 and 13 patients, respectively. The decrease in the extent of ground-glass opacity correlated inversely with the changes in FVC (r = -0.758; p = 0.0119) and diffusion capacity for carbon monoxide (r = -0.669; p = 0.0448). In one patient, ground-glass opacity progressed, and death occurred after 3 months. Traction bronchiectasis was seen in 12 patients, and it improved in four patients after treatment. Honeycomb lung was not noted in any patient during follow-up.

CONCLUSIONS

With treatment, serial CT scans of PM/DM patients with NSIP showed significant improvement in the abnormal opacities, and radiographic progression of lung fibrosis was limited. The CT scan features and clinical course of NSIP in PM/DM patients were relatively uniform, and this constitutes a subset of NSIP.

Interstitial lung disease in polymyositis and dermatomyositis

OBJECTIVES

To assess prevalence, characteristics, and long-term outcome of interstitial lung disease (ILD) in polymyositis (PM) and dermatomyositis (DM). To determine predictive variables of ILD course in PM/DM, and to define both clinical and biochemical features associated with ILD onset in PM/DM.

METHODS

The medical records of 156 consecutive PM/DM patients in 3 medical centers were reviewed.

RESULTS

Thirty-six PM/DM patients (23.1%) developed ILD. We observed that 19.4% of patients with ILD had resolution of pulmonary disorders, whereas 25% experienced ILD deterioration. Morbidity and mortality rates were as high as 13.9% and 36.4%, respectively, in PM/DM patients with ILD. Parameters of PM/DM that related to ILD poor outcome were identified as follows: Hamman-Rich-like pattern, initial diffusing capacity of carbon monoxide <45%, neutrophil alveolitis, and histologic usual interstitial pneumonia. Additionally, for the group with ILD, polyarthritis, higher values of erythrocyte sedimentation rate and C-reactive protein, presence of anti-Jo-1 antibody, and characteristic microangiopathy were significantly more frequent.

CONCLUSION

Our series underlines the high frequency of ILD in PM/DM patients, resulting in increased morbidity and mortality rates. It also indicates that PM/DM patients should routinely be screened for ILD, even those patients without anti-Jo-1 antibody, because 69% of our ILD patients were seronegative for the anti-Jo-1 antibody. Our findings further suggest that PM/DM patients presenting with factors predictive of ILD poor outcome may require more aggressive therapy.

Activation of pulmonary T cells in corticosteroid-resistant and -sensitive interstitial pneumonitis in dermatomyositis/polymyositis

To study the activation states and cytokine profiles of pulmonary T cells in corticosteroid-resistant and corticosteroid-sensitive interstitial pneumonitis (IP) in dermatomyositis (DM)/polymyositis (PM), we examined the activation markers and cytokine profiles of T cells in bronchoalveolar lavage fluids (BALF) from patients with IP in DM/PM before prednisolone therapy and then compared the activation states of T cells according to the therapeutic response of IP to prednisolone therapy. CD25+ CD4+ T cells in BALF were significantly increased in both corticosteroid-resistant and corticosteroid-sensitive IP in DM/PM as compared with those in controls without IP. Furthermore, CD25+ CD4+ T cells in BALF were significantly more increased in corticosteroid-resistant IP than those in cortico teroid- sensitive IP. Moreover, CD25+ CD8+ T cells in BALF were significantly increased only in corticosteroid-resistant IP, but not in corticosteroid-sensitive IP or controls without IP. IFN-gamma mRNA was detected in BALF T cells in corticosteroid-resistant and corticosteroid-sensitive IP but not in controls without IP, whereas IL-4 mRNA was virtually undetected in BALF T cells in both the IP groups. However, there were no significant differences in CD4/CD8 ratio of BALF T cells, HLA-DR+ BALF T cells or CD25+ and HLA-DR+ peripheral blood T cells between the two IP groups. These results indicate that activated Th1-type pulmonary T cells play an important role in the development of corticosteroid- resistant IP in DM/PM and that the increase in CD25+ CD8+ T cells in BALF is a useful indicator for corticosteroid-resistant IP in DM/PM and hence may be an indicator for early use of cyclosporin.

[Interstitial lung diseases in polymyositis and dermatomyositis]

PURPOSE

Interstitial lung disease is one of the most common respiratory manifestations in polymyositis and dermatomyositis. It still remains a severe complication of the disease, leading to death related to ventilatory insufficiency in 30-66% of patients.

CURRENT KNOWLEDGE AND KEY POINTS

Time onset of interstitial lung disease is variable, although interstitial lung disease onset precedes initial manifestations of polymyositis/dermatomyositis in roughly half of the patients. Moreover, clinical presentation of interstitial lung disease can be dichotomized, according to patients' pulmonary manifestations, into: 1) both acute and aggressive lung disease similar to Hamman-Rich syndrome; 2) slowly progressive lung disease; and 3) an asymptomatic pattern. The methods of choice adopted for early diagnosis of interstitial lung disease are high-resolution computed tomography scan and pulmonary function tests, which should be performed during both initial evaluation of polymyositis/dermatomyositis and follow-up. Because anti-JO1 antibody is considered to be a marker of interstitial lung disease in polymyositis/dermatomyositis, close pulmonary follow-up of anti-JO1-positive patients with polymyositis is therefore required for early detection of subclinical impairment. Furthermore, histological lung findings provide prognostic data; patients with bronchiolitis obliterans organizing pneumonia (BOOP) indeed appear to have a more favorable outcome than those with usual interstitial pneumonia or diffuse alveolar damage. Finally, as a guide to both the severity and progress of interstitial lung disease, the significance of other investigations, notably bronchoalveolar lavage, remains controversial.

FUTURE PROSPECTS AND PROJECTS

Specific therapy of interstitial lung disease has not yet been clearly established in polymyositis/dermatomyositis patients. Corticosteroid therapy is considered the first line of therapy for polymyositis/dermatomyositis patients with interstitial lung disease. The association of cyclophosphamide and corticosteroids may be the most effective in patients with steroid-resistant interstitial lung disease. Early diagnosis and management of this disease is therefore of the utmost importance.

Interstitial lung disease in polymyositis and dermatomyositis

Interstitial lung disease (ILD) is common in patients with polymyositis (PM) and dermatomyositis (DM), and is a major cause of morbidity. Although its cause is unknown, it is known to be closely associated with autoimmune disorders. Its manifestation has been found to be quite heterogeneous, as demonstrated by the differences among PM/DM patients in their immunologic profiles and histopathologic findings, which suggest variations in immunopathogenetic mechanisms. We review the clinicopathologic and immunologic findings in ILD associated with PM/DM, and discuss recent advances in classification, autoantibodies, and treatment. The most critical issues are to clarify the immunopathogenesis of severe forms of ILD, such as rapidly progressive ILD associated with amyopathic DM, and to establish the most appropriate therapy.

Interstitial lung disease in association with polymyositis-dermatomyositis: long-term follow-up CT evaluation in seven patients

PURPOSE

To determine the long-term follow-up computed tomographic (CT) findings of interstitial lung disease associated with polymyositis-dermatomyositis.

MATERIALS AND METHODS

CT scans in seven patients with interstitial lung disease and associated polymyositis-dermatomyositis were evaluated retrospectively. Six patients underwent sequential CT (follow-up range, 2-8 years; mean, 4.3 years). Histologic confirmation of pulmonary involvement was available in five patients.

RESULTS

The predominant finding on the initial CT scans in four patients was subpleural consolidation, which corresponded to bronchiolitis obliterans organizing pneumonia with or without coexistent chronic eosinophilic pneumonia. In most cases, consolidation improved with use of corticosteroid and/or immunosuppressive therapy; in two patients, however, consolidation evolved into honeycombing. In one patient, diffuse areas of ground-glass opacity and consolidation appeared rapidly during illness; this patient died of sudden, rapid deterioration. In one patient with subpleural linear opacities, parenchymal abnormalities slowly progressed, and linear opacities had evolved into honeycombing at 8-year follow-up. In one patient with histologically proved organizing diffuse alveolar damage, bilateral patchy areas of ground-glass opacity and consolidation were seen. In one patient, subpleural bands changed to subpleural lines on sequential CT scans.

CONCLUSION

CT provides an excellent demonstration of the lung changes in patients with interstitial lung disease and associated polymyositis-dermatomyositis.

Radiologic manifestations of the systemic autoimmune diseases

Advances in thoracic imaging during the past two decades, such as CT scans and MR imaging, have enhanced our understanding of the pleuropulmonary abnormalities that develop in the systemic autoimmune diseases. In this article, the thoracic radiologic manifestations of several connective tissue diseases (systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, polymyositis/dermatomyositis, progressive systemic sclerosis, and anklyosing spondylitis), two granulomatous vasculitides, (Wegener's Granulomatosis and Churg-Strauss syndrome), and antiglomerular basement membrane disease are reviewed.

The lung in polymyositis

Polymyositis is associated with a variety of pulmonary manifestations that may complicate an established case, occur simultaneously with the muscle manifestations, or precede the muscle disease. Included are respiratory muscle involvement, aspiration syndromes, and a variety of interstitial lung reactions.