Interstitial lung disease in polymyositis and dermatomyositis: analysis of six cases and review of the literature

Review of Pulmonary Manifestations in Antisynthetase Syndrome

Antisynthetase syndrome (ASyS) is now a widely recognized entity within the spectrum of idiopathic inflammatory myopathies. Initially described in patients with a triad of myositis, arthritis, and interstitial lung disease (ILD), its presentation can be diverse. Additional common symptoms experienced by patients with ASyS include Raynaud's phenomenon, mechanic's hand, and fever. Although there is a significant overlap with polymyositis and dermatomyositis, the key distinction lies in the presence of antisynthetase antibodies (ASAs). Up to 10 ASAs have been identified to correlate with a presentation of ASyS, each having manifestations that may slightly differ from others. Despite the proposal of three classification criteria to aid diagnosis, the heterogeneous nature of patient presentations poses challenges. ILD confers a significant burden in patients with ASyS, sometimes manifesting in isolation. Notably, ILD is also often the initial presentation of ASyS, requiring pulmonologists to remain vigilant for an accurate diagnosis. This article will comprehensively review the various aspects of ASyS, including disease presentation, diagnosis, management, and clinical course, with a primary focus on its pulmonary manifestations.

Respiratory symptoms as initial manifestations of interstitial lung disease in clinically amyopathic juvenile dermatomyositis: a case report with literature review

Background

Clinically amyopathic juvenile dermatomyositis (CAJDM) is a clinical subgroup of juvenile dermatomyositis (JDM), characterized by JDM rashes with little or no clinically evident muscle weakness. Interstitial lung disease (ILD) is an uncommon but potentially fatal complication of juvenile dermatomyositis (JDM). While adults with dermatomyositis-associated ILD usually present respiratory symptoms before or at the same time as skin muscle manifestations, only a few studies have covered the onset of respiratory symptoms of ILD in JDM patients, especially CAJDM. There is currently no clear effective treatment regime or any prognostic factors for CAJDM-associated ILD.

Case presentation

Here, we report the first case of a CAJDM patient who presented with respiratory symptoms as the initial manifestation. A 10-year-old male patient presented to the hospital with a complaint of progressive cough and chest pain. Violaceous macule and papules appeared a few days later and he was positive for anti-Ro-52 antibodies. Imaging showed diffuse interstitial infiltration in both lungs and lung function tests showed restrictive and obstructive ventilatory dysfunction. Muscular abnormalities were excluded by thigh magnetic resonance imaging (MRI) and electromyography. Skin biopsy showed pathognomonic findings consistent with DM. Lung biopsy indicated chronic inflammation of the mucosa. This patient was finally diagnosed with CAJDM complicated by ILD and prescribed methylprednisolone, immunoglobulin, prednisolone and mycophenolate mofetil (MMF) for treatment. The patient’s cutaneous and respiratory manifestations were largely improved. We retrospectively reviewed this and another six cases with CAJDM-associated ILD reported previously to better understand its clinical characteristics and effective management.

Conclusions

Initial respiratory symptoms with rapid progression in patients presenting Gottron papules should be considered manifestations of CAJDM-associated ILD. We also found a combination of corticosteroids, IVIG and MMF to be an effective method of arresting the progress of CAJDM-associated ILD and improving the prognosis of the patients.

Management of MDA-5 antibody-positive dermatomyositis with interstitial lung disease-an Auckland case series

Objective

The aim was to present our experience of managing six cases of anti-melanoma differentiation-associated gene 5 (anti-MDA-5) DM with associated interstitial lung disease (ILD), presenting between June 2017 and October 2020.

Methods

The electronic notes were reviewed for six patients being followed up by the Rheumatology service at Auckland District Health Board. Three patients were initially diagnosed and treated in neighbouring Counties Manukau District Health Board and later transferred to Auckland District Health Board. All had different initial treating clinicians at a time before any predefined treatment algorithm. Emphasis was placed on initial diagnosis and treatment, subsequent disease activity and changes in management. Local management was compared retrospectively with existing evidence relating to the treatment of anti-MDA-5 DM with ILD. Ethical approval was not obtained, according to the New Zealand Health and Disability Ethics Committee exemption for audits and related activities.

Results

Six patients with a variety of clinical presentations were identified appropriately as having anti-MDA-5 DM with ILD. They were commenced on different immunosuppressive regimens, with treatment adjusted according to response and on-going disease activity. Four have achieved clinical and biochemical remission, a fifth has improving active disease, and the sixth is in the early stages of their illness.

Conclusion

Anti-MDA-5 DM is commonly associated with ILD. This can be rapidly progressive, with a poor prognosis in spite of treatment, particularly among Asian patients. Disease activity can seemingly be monitored with serum ferritin. The most effective management of this condition remains poorly researched; however, increasing retrospective evidence favours early aggressive multi-agent immunosuppression and a low threshold for escalation of therapy.

The role of therapeutic plasma exchange in clinically amyopathic dermatomyositis with MDA-5 antibody: A case report and review of the literature

Clinically amyopathic dermatomyositis (CADM) is a rare, aggressive variant of dermatomyositis associated with interstitial lung disease (ILD) and refractoriness to immunosuppressants. Antibodies against melanoma differentiation-associated gene 5 (MDA-5) are often found in patients with CADM. We report a patient with advanced CADM with ILD and MDA-5 antibodies who failed to improve with immunosuppressants. We performed 2 TPE over 3 days, using 5% albumin as replacement fluid. Although five total TPE were planned, he was transferred for lung transplant evaluation after the second TPE; he died 16 days after transfer without receiving a transplant. A literature review identified four patients with CADM and MDA-5 antibodies treated with TPE; all experienced symptomatic improvement of their ILD. We attribute our patient's outcome to the advanced nature of his disease rather than a failure of TPE. Additional research may indicate a possible reclassification of CADM with MDA-5 antibodies in future ASFA guidelines.

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

Objective

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

Methods

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

Results

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

Conclusion

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

Trial registration

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

Inter-observer Variability Analysis of Automatic Lung Delineation in Normal and Disease Patients

Human interaction has become almost mandatory for an automated medical system wishing to be accepted by clinical regulatory agencies such as Food and Drug Administration. Since this interaction causes variability in the gathered data, the inter-observer and intra-observer variability must be analyzed in order to validate the accuracy of the system. This study focuses on the variability from different observers that interact with an automated lung delineation system that relies on human interaction in the form of delineation of the lung borders. The database consists of High Resolution Computed Tomography (HRCT): 15 normal and 81 diseased patients' images taken retrospectively at five levels per patient. Three observers manually delineated the lungs borders independently and using software called ImgTracer™ (AtheroPoint™, Roseville, CA, USA) to delineate the lung boundaries in all five levels of 3-D lung volume. The three observers consisted of Observer-1: lesser experienced novice tracer who is a resident in radiology under the guidance of radiologist, whereas Observer-2 and Observer-3 are lung image scientists trained by lung radiologist and biomedical imaging scientist and experts. The inter-observer variability can be shown by comparing each observer's tracings to the automated delineation and also by comparing each manual tracing of the observers with one another. The normality of the tracings was tested using D'Agostino-Pearson test and all observers tracings showed a normal P-value higher than 0.05. The analysis of variance (ANOVA) test between three observers and automated showed a P-value higher than 0.89 and 0.81 for the right lung (RL) and left lung (LL), respectively. The performance of the automated system was evaluated using Dice Similarity Coefficient (DSC), Jaccard Index (JI) and Hausdorff (HD) Distance measures. Although, Observer-1 has lesser experience compared to Obsever-2 and Obsever-3, the Observer Deterioration Factor (ODF) shows that Observer-1 has less than 10% difference compared to the other two, which is under acceptable range as per our analysis. To compare between observers, this study used regression plots, Bland-Altman plots, two tailed T-test, Mann-Whiney, Chi-Squared tests which showed the following P-values for RL and LL: (i) Observer-1 and Observer-3 were: 0.55, 0.48, 0.29 for RL and 0.55, 0.59, 0.29 for LL; (ii) Observer-1 and Observer-2 were: 0.57, 0.50, 0.29 for RL and 0.54, 0.59, 0.29 for LL; (iii) Observer-2 and Observer-3 were: 0.98, 0.99, 0.29 for RL and 0.99, 0.99, 0.29 for LL. Further, CC and R-squared coefficients were computed between observers which came out to be 0.9 for RL and LL. All three observers however manage to show the feature that diseased lungs are smaller than normal lungs in terms of area.

Histopathology of lung disease in the connective tissue diseases

The pathologic correlates of interstitial lung disease (ILD) secondary to connective tissue disease (CTD) comprise a diverse group of histologic patterns. Lung biopsies in patients with CTD-associated ILD tend to demonstrate simultaneous involvement of multiple anatomic compartments of the lung. Certain histologic patterns tend to predominate in each defined CTD, and it is possible in many cases to confirm connective tissue-associated lung disease and guide patient management using surgical lung biopsy. This article will cover the pulmonary pathologies seen in rheumatoid arthritis, systemic sclerosis, myositis, systemic lupus erythematosus, Sjögren syndrome, and mixed CTD.

Automatic lung segmentation using control feedback system: morphology and texture paradigm

Interstitial Lung Disease (ILD) encompasses a wide array of diseases that share some common radiologic characteristics. When diagnosing such diseases, radiologists can be affected by heavy workload and fatigue thus decreasing diagnostic accuracy. Automatic segmentation is the first step in implementing a Computer Aided Diagnosis (CAD) that will help radiologists to improve diagnostic accuracy thereby reducing manual interpretation. Automatic segmentation proposed uses an initial thresholding and morphology based segmentation coupled with feedback that detects large deviations with a corrective segmentation. This feedback is analogous to a control system which allows detection of abnormal or severe lung disease and provides a feedback to an online segmentation improving the overall performance of the system. This feedback system encompasses a texture paradigm. In this study we studied 48 males and 48 female patients consisting of 15 normal and 81 abnormal patients. A senior radiologist chose the five levels needed for ILD diagnosis. The results of segmentation were displayed by showing the comparison of the automated and ground truth boundaries (courtesy of ImgTracer™ 1.0, AtheroPoint™ LLC, Roseville, CA, USA). The left lung's performance of segmentation was 96.52% for Jaccard Index and 98.21% for Dice Similarity, 0.61 mm for Polyline Distance Metric (PDM), -1.15% for Relative Area Error and 4.09% Area Overlap Error. The right lung's performance of segmentation was 97.24% for Jaccard Index, 98.58% for Dice Similarity, 0.61 mm for PDM, -0.03% for Relative Area Error and 3.53% for Area Overlap Error. The segmentation overall has an overall similarity of 98.4%. The segmentation proposed is an accurate and fully automated system.

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.

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.

Pulmonary manifestations of the idiopathic inflammatory myopathies

Pulmonary involvement in myositis includes interstitial lung disease (ILD), respiratory muscle weakness, aspiration, infections, and drug-induced disease. ILD may precede myositis, and results in increased morbidity and mortality rates. Initial evaluation should include pulmonary function tests and high-resolution computed tomography. Nonspecific interstitial pneumonia (NSIP) is the most common histologic pattern on lung biopsy. Treatment usually consists of a combination of steroids and other immunosuppressive agents, and the response depends on the clinical presentation and underlying histology.

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.

[Interstitial lung disease]

Vasculitis and connective tissue disease are often associated with interstitial lung disease. Involvement of lung parenchyma is found in small vessel vasculitis and mostly in ANCA-associated forms such as Wegener's granulomatosis. In addition to vasculitis and connective tissue disease, rheumatoid arthritis can lead to interstitial lung disease and lung fibrosis. Diagnostic tools include measurement of auto-antibodies, lung function test, chest X-rays and computed tomography of the thorax, as well as bronchoscopy with biopsy and bronchoalveolar lavage. The following article provides an overview of the clinical, histological and radiologic patterns of interstitial lung disease in vasculitis, rheumatoid arthritis and connective tissue disease. Treatment options will also be discussed.

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.

Computed tomographic features of idiopathic fibrosing interstitial pneumonia: comparison with pulmonary fibrosis related to collagen vascular disease

OBJECTIVE

To compare the computed tomographic (CT) features of idiopathic fibrosing interstitial pneumonia with those of pulmonary fibrosis related to collagen vascular disease (CVD).

METHODS

We reviewed the CT scans of 177 patients with diffuse interstitial pulmonary fibrosis, of which 97 had idiopathic fibrosing interstitial pneumonia and 80 had CVD. The CT images were systematically scored for the presence and extent of pulmonary and extrapulmonary abnormalities. Computed tomographic diagnosis of usual interstitial pneumonia (UIP) or nonspecific interstitial pneumonia (NSIP) was assigned.

RESULTS

A CT pattern of UIP was identified in 59 (60.8%) of patients with idiopathic fibrosing interstitial pneumonia compared with 15 (18.7%) of those patients with CVD; conversely, the CT diagnosis of NSIP was made in 51 (64%) of patients with CVD compared with 36 (37%) of patients with idiopathic disease (P < 0.01). In 113 patients who had lung biopsy, the CT diagnoses of UIP and NSIP were concordant with the histologic diagnoses in 36 of 50 patients and 34 of 41 patients, respectively. Pleural effusions, esophageal dilation, and pericardial abnormalities were more frequent in patients with CVD than in patients with idiopathic fibrosing interstitial pneumonia.

CONCLUSIONS

Compared with patients with CVD, those patients with an idiopathic fibrosing interstitial pneumonia showed a higher prevalence of a UIP pattern and lower prevalence of an NSIP pattern as determined by CT. Identification of coexisting extrapulmonary abnormalities on CT can support a diagnosis of CVD.

Collagen Vascular Diseases and Disorders of Connective Tissue

The collagen vascular diseases, also referred to as connective tissue diseases, are a diverse group of systemic inflammatory disorders thought to be immunologically mediated. The concept of collagen vascular disease began to take shape in the 1930s, when it was recognized that rheumatic fever and rheumatoid arthritis can affect connective tissues throughout the body.1,2 During the following decade, as conditions such as systemic lupus erythematosus (SLE) and scleroderma came to be viewed as systemic diseases of connective tissue, the terms diffuse connective disease and diffuse collagen disease were proposed.3,4 During the same period, the designation of diffuse vascular disease was proposed for diseases such as scleroderma, polymyositis, SLE, and polyarteritis nodosa, which featured widespread vascular involvement.5 With the realization that many of these entities can exhibit both systemic connective tissue manifestations and vascular abnormalities, the unifying designation of collagen vascular disease was introduced.6

Two distinct clinical types of interstitial lung disease associated with polymyositis-dermatomyositis

Most patients with interstitial lung disease (ILD) associated with collagen vascular diseases (CVD) have a chronic indolent course with a relatively favorable prognosis; however, acute progression has been reported in some polymyositis-dermatomyositis patients. This study evaluated the prevalence, clinical features, and outcome relative to the presentation type of ILD in polymyositis-dermatomyositis (PM-DM). Ninety-nine patients with newly diagnosed polymyositis-dermatomyositis seen at the Asan Medical Center in Korea between January 1990 and December 2004 were enrolled. The clinical, radiological, and pathological findings were retrospectively reviewed. ILD were divided into acute (dyspnea within 1 month before diagnosis) or chronic types. ILD was found on chest radiographs in 33 patients (33.3%), and 11 (33.3%) of these were considered acute. The acute group presented with more severe respiratory symptoms, hypoxemia, and poorer lung function. Patients with an acute presentation had ground glass opacity and consolidation on high-resolution computed tomography (HRCT), in contrast to reticulation and honeycombing in the chronic type. Surgical lung biopsy of one acute-type patient revealed diffuse alveolar damage, whereas biopsies in the chronic type showed usual interstitial pneumonia (UIP) in four cases and nonspecific interstitial pneumonia (NSIP) in another four. Eight acute-type patients (72.7%) died of respiratory failure within 1-2 months despite steroid therapy. The 3-year mortality rate of the chronic-type patients (21.2%) was not statistically significantly different from that of the patients without ILD (10.2%). In polymyositis-dermatomyositis, the acute, severe form of ILD was not infrequent.

Step-up versus primary intensive approach to the treatment of interstitial pneumonia associated with dermatomyositis/polymyositis: a retrospective study

Corticosteroids (CS) are the standard initial treatment for interstitial pneumonia (IP) associated with dermatomyositis (DM)/polymyositis (PM). However, many patients fail to respond and have significantly high mortality even if immunosuppressive drugs (ISDs) are subsequently added, while a more intensive initial approach using ISDs is suggested to improve their survival. We conducted a retrospective study to examine the association between initial therapeutic approaches and clinical outcomes of active IP in DM/PM patients. We reviewed medical records of 34 consecutive DM/PM patients who had active IP defined by the presence of pulmonary function abnormality or active symptoms, and compared clinical outcome between those patients to whom ISDs were added if CS alone did not result in a favorable response (a step-up approach) and those who were started on ISDs simultaneously with CS (a primary intensive approach). Clinical endpoints were death, pulmonary death, and progression or improvement of pulmonary function. The step-up approach was used in 20 patients, to 11 of whom ISDs were eventually added after a median of 2.0 weeks, while the primary intensive approach was used in 14 patients. The primary intensive approach group had significantly better survival than the step-up approach group (P = 0.030 by the log-rank test). These two groups did not differ significantly in demographic characteristics and baseline clinical and laboratory features. Intensive approach by starting ISDs simultaneously with CS in the initial treatment for active IP in DM/PM patients was associated with better survival, emphasizing the impact of initial treatment on their survival. Prospective clinical investigation of this approach is now needed, but the limited clinical utility of CS as an initial treatment might ethically challenge clinical-trial designing.

Transbronchial Biopsy Interpretation in the Patient With Diffuse Parenchymal Lung Disease

Context.—The most common lung tissue samples seen by pathologists worldwide are obtained with the flexible bronchoscope. Specimens taken for examination of diffuse or multifocal parenchymal lung abnormalities pose special challenges for the general surgical pathologist, and these challenges are often compounded by high clinical expectations for accurate and specific diagnosis.

Objective.—To present and discuss the most common histopathologic patterns and diagnostic entities seen in transbronchial biopsy specimens in the setting of diffuse or multifocal lung disease. Specifically, acute lung injury, eosinophilic pneumonia, diffuse alveolar hemorrhage, chronic cellular infiltrates, organizing pneumonia, alveolar proteinosis, sarcoidosis, Wegener granulomatosis, intravenous drug abuse-related microangiopathy, Langerhans cell histiocytosis, and lymphangioleiomyomatosis are presented. Clinical and radiologic context is provided for the more specific diagnostic entities.

Data Sources.—The published literature and experience from a consultation practice.

Conclusions.—The transbronchial biopsy specimen can provide valuable information for clinical management in the setting of diffuse or multifocal lung disease. Computed tomographic scans are useful for selecting appropriate patients to undergo biopsy and in limiting the differential diagnosis. Knowledge of the clinical context, radiologic distribution of abnormalities, and histopathologic patterns is essential. With this information, the surgical pathologist can substantially influence the diagnostic workup and help guide the clinician to an accurate clinical/radiologic/pathologic diagnosis.

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.

Interstitial lung disease in patients with polymyositis, dermatomyositis and amyopathic dermatomyositis

OBJECTIVE

To assess the prevalence, characteristics and prognostic factors of interstitial lung disease (ILD) in Korean patients with polymyositis (PM), dermatomyositis (DM) and amyopathic dermatomyositis (ADM).

METHODS

We reviewed the medical records of 72 consecutive PM and DM patients, including six patients with ADM, who were seen at the Rheumatology Clinic of Seoul National University Hospital between 1984 and 2003.

RESULTS

Twenty-nine PM/DM patients (40.3%) developed ILD. Anti-Jo-1 antibody and arthralgia were associated with the presence of ILD (P = 0.022 and P = 0.041, respectively), whereas dysphagia was more frequently found in patients without ILD (P = 0.041). Lung biopsies revealed diffuse alveolar damage (DAD) (n = 2), usual interstitial pneumonia (UIP) with DAD (n = 2), UIP (n = 1), and non-specific interstitial pneumonia (n = 2). Of the 29 patients, 11 (37.9%) died. The mean survival time in ILD patients was significantly shorter than in those without ILD (13.8+/-1.8 vs 19.2+/-0.9 yr, P = 0.017). Poor survival in ILD patients was associated with a Hamman-Rich-like presentation (P = 0.0000), ADM features (P = 0.0001) and an initial forced vital capacity (FVC) < or =60% (P = 0.024).

CONCLUSIONS

ILD was observed in 40.3% of Korean PM/DM patients and was associated with poor survival. A Hamman-Rich-like presentation, ADM features and an initial FVC < or =60% were associated with poor survival in ILD.

Long-term clinical course of a patient with anti PL-12 antibody accompanied by interstitial pneumonia and severe pulmonary hypertension

We report a case of a patient with anti PL-12 antibody accompanied by interstitial pneumonia and severe pulmonary hypertension. At first presentation, hyperkeratotic skin lesions were found, although the diagnosis of CVD was not conclusive. Lung histology showed diffuse fibrosing interstitial pneumonia predominantly in the subpleural regions. During the seven-year follow-up period, severe pulmonary hypertension developed, although the progression of lung fibrosis was relatively limited. Anti-PL12 antibody was detected, and therefore the patient was diagnosed as having antisynthetase syndrome. Lung histology and pulmonary arteriogram suggested that vascular involvement of the disease contributed to the development of severe pulmonary hypertension.

Interstitial lung disease in polymyositis and dermatomyositis

Interstitial lung disease occurs in approximately one-third of patients with polymyositis and dermatomyositis (PM/DM) and has an adverse effect on survival. It is commonly a component of early PM/DM and can precede the onset of muscle or skin disease. Its most common histopathology is nonspecific interstitial pneumonia. This is a more benign pattern, with respect to response to immunosuppression and also long-term survival, than the pattern of usual interstitial pneumonia seen in idiopathic pulmonary fibrosis. The clinical course of PM/DM lung disease is heterogeneous. Progressive and nonprogressive disease needs to be distinguished by clinical and physiologic monitoring to avoid over-treatment. Patients with ongoing functional deterioration mostly benefit from immunosuppression. The experience with corticosteroid monotherapy is discouraging but cyclophosphamide, given as daily oral or intravenous pulse therapy together with corticosteroids, was found to be beneficial in many patients. Other immunosuppressants may be of benefit as well, but the weight of the current evidence supports the use of cyclophosphamide first.

Variations in histological patterns of interstitial pneumonia between connective tissue disorders and their relationship to prognosis

AIMS AND METHODS

Pulmonary parenchymal disease is common in patients with connective tissue disorders (CTDs). However, most reports precede recognition of non-specific interstitial pneumonia (NSIP). We have therefore reviewed 54 lung biopsies from 37 patients with polymyositis/dermatomyositis (PM/DM) (n = 13), Sjögren's syndrome (n = 5), rheumatoid arthritis (n = 17) and systemic lupus erythematosus (SLE) (n = 2) to assess the overall and relative frequencies of patterns of interstitial pneumonia and their impact on prognosis.

RESULTS AND CONCLUSIONS

NSIP was the most common pattern with an overall biopsy prevalence of 39% and patient prevalence of 41%. There was variation in prevalence between individual CTDs, with PM/DM commonly showing organizing pneumonia (n = 5), rheumatoid arthritis showing follicular bronchiolitis (n = 6) and Sjögren's syndrome showing chronic bronchiolitis (n = 4). These patterns presented either separately or in association with NSIP, occasionally with different patterns in biopsies from separate lobes. Only four patients showed a pattern of usual interstitial pneumonia (UIP): two with rheumatoid arthritis and one each with PM/DM and SLE. Overall mortality was 24%, the most frequently associated pattern being fibrotic NSIP (n = 5). In nine cases, pulmonary presentation preceded the systemic manifestation of the CTDs. When patients with CTDs present with chronic interstitial lung disease, the most common pattern is NSIP, although there is variation in pattern prevalence between individual disorders and patterns of interstitial pneumonia frequently overlap. These data suggest a different biology for intestitial pneumonias in CTDs when compared with the idiopathic interstitial pneumonias where UIP is the most common pattern. Mortality is similar to that seen in idiopathic NSIP and, coupled with pulmonary presentation occurring prior to the systemic manifestation of disease, this may have a bearing on the origin of some cases of putative idiopathic NSIP.

Antisynthetase syndrome

Seven autoantibodies directed against synthetases have been identified to date, the best known being anti-Jo1. Synthetases play a vital role in protein synthesis by catalyzing the acetylation of transfer RNAs (tRNAs). The most common form of antisynthetase syndrome is characterized by anti-Jo1 production, interstitial lung disease (ILD), inflammatory muscle disease, and, in many cases, fever, polyarthritis, Raynaud's phenomenon, and thick cracked skin on the fingers (mechanic's hands). The interstitial lung disease is generally of the "usual interstitial pneumopathy" type and shares similarities with idiopathic pulmonary fibrosis or scleroderma-related pulmonary disease. It governs the prognosis of the disease, being associated with an excess mortality rate of about 40%. The pathogenic mechanisms underlying antisynthetase syndrome remain unknown but may involve cell-mediated immunity. The treatment is not standardized. The ILD responds to glucocorticoids in some patients but requires other immunosuppressant drugs in others.

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.

Classification of idiopathic interstitial pneumonias: making sense of the alphabet soup

Since Liebow and Carrington's original classification of idiopathic interstitial pneumonias, there have been controversies over which histological patterns should be included and how they relate to clinicopathological diseases such as cryptogenic fibrosing alveolitis/idiopathic pulmonary fibrosis (CFA/IPF). Because of these differences and the wealth of overlapping terminology, a consensus classification system has been proposed, devised by a group of clinicians, radiologists and pathologists. Seven histological patterns are recognized: usual interstitial pneumonia (UIP), non-specific interstitial pneumonia (NSIP), diffuse alveolar damage (DAD), organizing pneumonia (OP), desquamative interstitial pneumonia (DIP), respiratory bronchiolitis (RB) and lymphocytic interstitial pneumonia (LIP), each with a clinicopathological counterpart, the most well defined being UIP and CFA/IPF. The system is applicable both in terms of the pathologist identifying histological patterns in isolation and in terms of the pathologist's role in contributing to the final clinicopathological diagnosis. It will probably provide greater consistency in diagnosis, early studies suggesting that the system is reproducible, and also identify purer cohorts for studies investigating causation. It also highlights the fact that the 'gold standard for diagnosis' is no longer a surgical lung biopsy in isolation but more the clinicopathological conference, when clinical, imaging and histological data are jointly discussed to produce the final clinicopathological diagnosis.

[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.

Polymyositis-dermatomyositis-associated interstitial lung disease

We report findings in 70 patients with both diffuse interstitial lung disease and either polymyositis (PM) or dermatomyositis (DM). Initial presentations were most commonly either musculoskeletal (arthralgias, myalgias, and weakness) or pulmonary (cough, dyspnea, and fever) symptoms alone; in only 15 patients (21.4%) did both occur simultaneously. Pulmonary disease usually took the form of acute to subacute antibiotic-resistant community-acquired pneumonia. Chest radiographs and computed tomography most commonly demonstrated bilateral irregular linear opacities involving the lung bases; occasionally consolidation was present. Jo-1 antibody was present in 19 (38%) of 50 patients tested. Synchronous associated malignancy was present in 4 of 70 patients (5.7%). Surgical lung biopsies disclosed nonspecific interstitial pneumonia (NSIP) in 18 of 22 patients (81.8%), organizing diffuse alveolar damage (DAD) in 2, bronchiolitis obliterans organizing pneumonia (BOOP) in 1, and usual interstitial pneumonia (UIP) in 1. Treatment usually included prednisone in 40-60 mg/d dosages for initial control, followed by lower dose prednisone plus an immunosuppressive agent such as azathioprine or methotrexate for disease suppression. Survival was significantly better than that observed for historical control subjects with idiopathic UIP, and was more consistent with survival previously reported in idiopathic NSIP. There was no difference in survival between Jo-1 positive and Jo-1 negative groups.

KL-6 is a potential marker for interstitial lung disease associated with juvenile dermatomyositis

Serum levels of KL-6 were examined in 8 cases of juvenile dermatomyositis: 3 with interstitial lung disease (ILD) and 5 without ILD. The KL-6 levels were elevated in the ILD cases and correlated with the degree of computed tomography findings. The measurement of serum KL-6 levels is useful for evaluating juvenile dermatomyositis-associated ILD.

Thin-section CT findings in rheumatoid arthritis-associated lung disease: CT patterns and their courses

PURPOSE

The purpose of this study was to describe the long-term follow-up CT evaluation in rheumatoid arthritis (RA)-associated lung disease.

METHOD

Thin-section CT scans from 29 patients with RA and suspected associated lung disease were reviewed. Twenty-two patients underwent sequential CT evaluation during 3 to 108 months of follow-up (mean 28 months). Histologic comfirmation of pulmonary involvement was available in 19 patients.

RESULTS

Three major patterns were identified: reticulation with or without honey-combing (n = 19), centrilobular branching lines with or without bronchial dilatation (n = 5), and consolidation (n = 5). Reticulation and centrilobular branching lines corresponded to usual interstitial pneumonia (n = 14) and bronchiolitis obliterans (n = 1), respectively. Consolidation corresponded to bronchiolitis obliterans organizing pneumonia (BOOP; n = 3) and coexistent chronic eosinophilic pneumonia (CEP) and BOOP (n = 1). Patients with reticulation had rapid deterioration when there was new appearance of multifocal areas of ground-glass attenuation. Centrilobular branching lines progressed to bronchiectasis in one case. There was mild progression of existing bronchiectasis associated with centrilobular branching lines in one case. Area of consolidation in two patients with BOOP and one with coexistent CEP and BOOP evolved into honeycombing at serial CT.

CONCLUSION

Thin-section CT is a noninvasive technique for monitoring disease morphology in RA-associated lung disease. Initial CT findings and their evolution on sequential examinations may be useful in evaluating prognosis.

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.

Subcutaneous emphysema with spontaneous pneumomediastinum and pneumothorax in adult dermatomyositis

We describe a 32-year-old patient with adult dermatomyositis who developed dyspnea and worsening of pre-existing infarcted skin lesions of the fingers. Chest radiographs showed diffuse hazy reticulonodular infiltration in both lungs, subcutaneous emphysema, pneumomediastinum, and pneumothorax. The pulmonary symptoms and cutaneous lesions gradually improved with a high dose of prednisolone. Although subcutaneous emphysema and pneumomediastinum occur frequently in association with traumatic disruption of cutaneous and mucosal barriers and assisted ventilation, it has rarely been observed in patients with interstitial pneumonitis in connective tissue diseases. Although dermatomyositis and subcutaneous emphysema are all relatively well-known diseases to dermatologists, the occurrence of spontaneous pneumomediastinum and pneumothorax and subsequent subcutaneous emphysema in connective tissue diseases such as dermatomyositis is unfamiliar. We discuss the possible mechanisms of this condition.

Dermatomyositis associated with bronchiolitis obliterans organizing pneumonia (BOOP)

Bronchiolitis obliterans organizing pneumonia (BOOP) is rarely associated with dermatomyositis and may be resistant to conventional corticosteroid therapy under this circumstance. We present a case of BOOP associated with dermatomyositis that responded to a combination of cyclophosphamide and corticosteroid therapy after corticosteroid treatments, alone, had failed. We believe this case shows it is important to recognize that facial rash in the presence of respiratory distress may represent dermatomyositis with BOOP and aggressive treatment may be necessary for resolution of pulmonary symptoms.

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.

Idiopathic inflammatory myopathies

Dermatomyositis, polymyositis, and inclusion body myositis are the major categories of idiopathic inflammatory myopathy. These inflammatory myopathies are distinct clinically, histologically, and pathogenically. Features of dermatomyositis and polymyositis can overlap with those of other autoimmune connective tissue diseases. In this article, the authors review the characteristic features of these myopathies, update the recent developments in this area, and provide a framework for treatment.

Adult respiratory distress syndrome in polymyositis patients with the anti-Jo-1 antibody

We report 3 patients with polymyositis and the anti-Jo-1 antibody who developed fatal adult respiratory distress syndrome (ARDS). Other than the presence of the anti-Jo-1 antibody, there were no other consistent clinical features at the onset of disease that were predictive of ARDS development.