Anti-aminoacyl-tRNA synthetase antibodies in clinical course prediction of interstitial lung disease complicated with idiopathic inflammatory myopathies

Natural history of indolent-anti-synthetase syndrome-associated interstitial lung disease

BACKGROUND

Anti-synthetase syndrome-associated interstitial lung disease (ASS-ILD) may occur without myositis. Although a recent Japanese guide proposed a watch-and-wait approach for chronic ASS-ILD without obvious progression, the natural history of this subgroup and the appropriateness of the watch-and-wait approach remain unclear. We aimed to describe the natural history of ASS-ILD, that is sufficiently indolent to be a candidate for the watch-and-wait approach.

METHODS

Among consecutive patients with ASS-ILD, we retrospectively identified those without myositis, acute/subacute onset, and significant lung function impairment, which qualified them as indolent-ASS-ILD cases, and described their natural course. Additionally, we evaluated the risk factors for fibrosis progression on computed tomography (CT) using the Cox proportional hazards model.

RESULTS

Among 80 patients with ASS-ILD, we identified 33 with indolent-ASS-ILD, all of whom were initially followed up with a watch-and-wait approach. Among 30 patients with sufficient follow-up data, 27 (90%) showed a stable course without treatment over 24 months. Subsequently, four patients experienced ≥10% relative forced vital capacity (FVC) decline without treatment during a median follow-up duration of 81 months. Seven patients showed fibrosis progression with >10% increase in the total lung area on CT. Higher levels of Krebs von den Lungen-6 (KL-6) and surfactant protein-D (SP-D) were associated with fibrosis progression on CT.

CONCLUSION

Most patients with indolent-ASS-ILD did not experience ≥10% relative FVC decline over five years without treatment. However, fibrosis progression on CT, which seemed to precede significant FVC decline, occurred more frequently, especially in patients with higher KL-6 and SP-D levels.

Disease-specific autoantibody production in the lungs and salivary glands of anti-synthetase syndrome

Interstitial lung disease is a common complication of anti-synthetase syndrome (ASS), and lymphocytic infiltration is often observed in the lesion. We have recently reported that disease-specific autoantibodies are produced by infiltrating lymphocytes in some autoimmune diseases. Here, we investigate the antigen specificity of B cells in the lung lesions of ASS patients. A total of 177 antibodies were produced from antibody-secreting cells in bronchoalveolar fluid (BALF) of three each of serum anti-Jo-1 and serum anti-EJ antibody-positive patients. Twelve to 30% and 50 to 62% of these antibodies were disease-specific autoantibodies, respectively. These autoantibodies recognized conformational epitopes of the whole self-antigen and had affinity maturations, indicating that self-antigens themselves are the target of humoral immunity. In addition, 100 antibodies were produced from two salivary gland tissues, obtained by chance, of ASS patients. Salivary glands are not generally recognized as lesions of ASS, but unexpectedly, ASS-related autoantibody production was also observed similar to that of BALF. Immunostaining confirmed the presence of ASS-related autoantibody-producing cells in salivary glands. Our results suggest that disease-specific autoantibody production at lesion sites is a common pathogenesis of autoimmune diseases, and that tissue-specific production of autoantibodies can provide insights regarding the distribution of organ manifestations in autoimmune diseases.

Relationship between idiopathic interstitial pneumonias (IIPs) and connective tissue disease-related interstitial lung disease (CTD-ILD): A narrative review

While idiopathic interstitial pneumonia (IIP) centering on idiopathic pulmonary fibrosis (IPF) is the most prevalent interstitial lung disease (ILD), especially in the older adult population, connective tissue disease (CTD)-related ILD is the second most prevalent ILD. The pathogenesis of IPF is primarily fibrosis, whereas that of other ILDs, particularly CTD-ILD, is mainly inflammation. Therefore, a precise diagnosis is crucial for selecting appropriate treatments, such as antifibrotic or immunosuppressive agents. In addition, some patients with IIP have CTD-related features, such as arthritis and skin eruption, but do not meet the criteria for any CTD, this is referred to as interstitial pneumonia with autoimmune features (IPAF). IPAF is closely associated with idiopathic nonspecific interstitial pneumonia (iNSIP) and cryptogenic organizing pneumonia (COP). Furthermore, patients with iNSIP or those with NSIP with OP overlap frequently develop polymyositis/dermatomyositis after the diagnosis of IIP. Acute exacerbation of ILD, the most common cause of death, occurs more frequently in patients with IPF than in those with other ILDs. Although acute exacerbation of CTD-ILD occurs at a low rate of incidence, patients with rheumatoid arthritis, microscopic polyangiitis, or systemic sclerosis experience more acute exacerbation of CTD-ILD than those with other CTD. In this review, the features of each IIP, focusing on CTD-related signatures, are summarized, and the pathogenesis and appropriate treatments to improve the prognoses of patients with various ILDs are discussed.

Comprehensive Exploration of Antinuclear Antibodies (ANAs): Unveiling Clinical Significance, Associations with Cancer, and the Nuances of Differential Diagnosis in Positive ANA Patients

This comprehensive review delves into the complex realm of antinuclear antibodies (ANAs), expanding beyond their traditional involvement in autoimmune rheumatic disorders. By digging into historical changes, diagnostic complexity, and clinical significance, the debate reveals the shifting relationships between ANAs, particularly with cancer. Specialized studies provide practical insights on ANA testing processes, standardization, and upcoming challenges. Examining prevalence trends in the United States provides a time dimension to ANA dynamics, linking autoimmune and oncological considerations. The debate delves into the complexity of lupus erythematosus, emphasizing ANAs' diverse presentations and their potential as flexible diagnostic and prognostic indicators. The complex relationship between ANAs and cancer is highlighted, demonstrating their potential as early markers or indicators of malignancies. Looking ahead, this synthesis anticipates advances in personalized medicine and collaborative research, putting ANAs at the forefront of advanced diagnostics and treatments for autoimmune disorders and cancer. This synthesis envisions a future for ANA research in which these antibodies play a critical role in promoting personalized treatment, enhancing diagnostics, and fostering collaborative initiatives that cross traditional boundaries. As ANAs grow more prominent at the junction of autoimmune illnesses and cancer, this synthesis lays the path for further research and novel advances in understanding, diagnosing, and treating complicated medical conditions.

Combination of Prednisolone and Calcineurin Inhibitors Prevents Lung Function Decline in Patients with Anti-aminoacyl-tRNA Synthetase Antibody-Positive Polymyositis/Dermatomyositis

OBJECTIVE

Anti-aminoacyl-tRNA synthetase antibody-positive polymyositis/dermatomyositis-associ ated interstitial lung disease (ARS-ILD) has a good prognosis, with few cases progressing to respiratory failure. This study aimed to determine factors predictive of lung function changes in patients with ARS-ILD.

METHODS

We retrospectively studied 49 patients with ARS-ILD treated at Kurume University Hospital Hospital between 2000 and 2018. We followed 30 patients for more than 2 years after prednisolone (PSL) therapy, with or without calcineurin inhibitors (CNIs), evaluating clinical, physiological, computed tomography, pulmonary func tion, and serological data.

RESULTS

After treatment for 24 months, no significant differences were noted between clinical parameters and improvement in forced vital capacity (FVC), %FVC, % carbon monoxide diffusing capacity/alveolar volume (%DLCO), and %DLCO/alveolar volume. Conversely, the annual change of %FVC significantly correlated with the Medical Research Council dyspnea scale grade and %FVC at the first visit and treatment. Furthermore, the annual change of %DLCO/VA significantly correlated with the duration from the first visit to treatment initiation.

CONCLUSION

Compared with PSL monotherapy, combining PSL and CNI showed greater mitigation of %FVC decline. The time from onset of ARS-ILD to the first visit is critical for preventing a decline in lung function, and as such, patients should be monitored carefully.

Comparison of Muscle Biopsy Features with Myositis Autoantibodies in Inflammatory Myopathies: A Pilot Experience

Background

Idiopathic inflammatory myopathies (IIM), also called autoimmune myositis, are heterogeneous. These include dermatomyositis (DM), inclusion body myositis, immune mediated necrotizing myopathy (IMNM), anti-synthetase syndrome (ASS), and overlap polymyositis. Classification of IIM has evolved from clinical to clinico-pathologic to the recent clinico-sero-pathologic with the discovery of myositis-specific antibodies (MSA) and myositis-associated antibodies. The various antibodies have shown association with specific phenotypes.

Objective

To analyze muscle biopsy features with respect to each MSA and MAA to understand the frequency of findings in each entity.

Materials and Methods

Biopsy-proven cases of IIM where myositis profile was available were included in the study after obtaining Institutional Ethics Committee (IEC) approval. In addition to the stains and enzyme histochemistry, immunohistochemistry with MHC class I and II and MxA was performed. Features like perifascicular atrophy, perifascicular necrosis, scattered necrosis, inflammation, etc. were analyzed. Myositis profile was performed by line-blot technique using a 16-antigen panel. Cases were divided into different autoantibody subgroups. Various clinical, demographic, and muscle biopsy features were studied with respect to each MSA and MAA.

Results

There were a total of 64 cases. Mi2 (N = 18) was the most common autoantibody. Some of the salient observations included PFA with perivascular inflammation in Mi2; pediatric cases and microinfarcts in NXP2; no PFA or inflammation in MDA5; perifascicular necrosis in JO1; extensive necrosis with sparse inflammation in SRP; more inflammation in overlap myositis; MxA positivity in DM; and absent in ASS.

Conclusion

This is a pilot study documenting differences in biopsy phenotype with each MSA and MAA which is comparable to the literature. These findings can be used to characterize IIM in seronegative biopsies.

Anti-synthetase syndrome-associated interstitial lung disease possibly caused by atezolizumab in a patient with lung adenocarcinoma: a case report

BACKGROUND

Anti-aminoacyl-tRNA synthetase (ARS) antibody-positive patients present with a variety of symptoms, including interstitial lung disease (ILD), which is termed anti-synthetase syndrome (ASS). But it is rare that ASS-ILD is considered an immune-related adverse event after the use of immune checkpoint inhibitors (ICIs).

CASE PRESENTATION

A 47-year-old male with advanced lung adenocarcinoma was treated with platinum and ICI combination immunotherapy and was followed up as an outpatient. Nine months after the start of treatment, he developed a fever and cough, and imaging findings showed lung consolidations in the bilateral lower lung fields. The patient was positive for anti- ARS antibodies and was considered to have developed ASS-ILD due to ICIs remitted with steroid therapy. The patient was found to be positive for anti-ARS antibodies before ICI administration, and the antibody titer was elevated compared to that before ICI administration.

CONCLUSIONS

The examination of anti-ARS antibodies pior to the administration of ICIs may be useful in predicting the development of ASS-ILD.

An observational study of clinical recurrence in patients with interstitial lung disease related to the antisynthetase syndrome

OBJECTIVE

To describe the clinical characteristics and risk factors of clinical recurrence in interstitial lung disease related to antisynthetase syndrome (ARS-ILD).

METHODS

Patients diagnosed as ARS-ILD in Nanjing Drum Tower Hospital between January 2015 and November 2020 were retrospectively analyzed. Clinical information and treatment course were reviewed. The primary endpoint was the disease recurrence, and the secondary point was mortality. Univariate and multivariable Cox regression analyses were performed to identify risk factors for recurrence.

RESULTS

Totally, 132 patients with ARS-ILD received immunomodulation treatment from diagnosis. During follow-ups, sixty-nine patients showed recurrence, with a recurrency rate yielding 52.3%. The median duration from treatment initiation to recurrence was 11 (5-18) months. The median tapering course in the recurrence group was 8 (3-12.5) months, which was significantly shorter than the 16 (10-32) months in the no-recurrence group (p < 0.001). Fifty-eight patients experienced recurrence when the glucocorticoids (GC) dose dropped to 10 (9.375-15) mg/day. Twelve patients discontinued GC with a median treatment course of 11.5 (8-16.75) months, and 11 patients developed recurrence after discontinuing GC for 3 (1-4) months. Twelve patients died, with a mortality rate of 9.1%, and recurrence was not associated with increased mortality. The adjusted multivariate analysis showed that age, increased serum lactate dehydrogenase (LDH) level, relatively shorter tapering duration, and inappropriate GC discontinuation were associated with recurrence.

CONCLUSION

Recurrence of ARS-ILD was common during medication intensity reduction. Age, LDH, medication tapering duration, and discontinuation were risk factors for recurrence. Further efforts to reduce recurrence should take into consideration of these factors. Key Points • Recurrence is observed commonly with a recurrency rate 52.3% in patients with interstitial lung disease related to antisynthetase syndrome (ARS-ILD) when glucocorticoids (GC) tapering or discontinuation. • Age, increased serum lactate dehydrogenase (LDH) level, medication tapering duration, and GC discontinuation were identified to be significantly associated with the recurrence of ARS-ILD.

Screening and characterization of myositis-related autoantibodies in COVID-19 patients

An efficient host immune response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) appears to be crucial for controlling and resolving this viral infection. However, many studies have reported autoimmune characteristics in severe COVID-19 patients. Moreover, clinical observations have revealed that COVID-19-associated acute distress respiratory syndrome shares many features in common with inflammatory myopathy including interstitial lung disease (ILD), most particularly rapidly progressive (RP)-ILD. This study explored this phenomenon by seeking to identify and characterize myositis-specific and related autoantibodies in 25 COVID-19 patients with mild or severe symptoms. Line blot analysis with the EUROLINE Myopathies Ag kit identified 9 (36%) patients with COVID-19 with one or more autoantibodies against several myositis-related antigens (Jo-1, Ku, Mi-2β, PL-7, PL-12, PM-Scl 75, PM-Scl 100, Ro-52, and SRP); no anti-MDA5 antibodies were detected. As the presence of antibodies identified by line blots was unrelated to disease severity, we further characterized the autoantibodies by radioimmunoassay, in which [³⁵ S]methionine-labeled K562 cellular antigens were precipitated and visualized by gel electrophoresis. This result was confirmed by an immunoprecipitation assay and immunoblotting; 2 patients exhibited anti-Ku70 and anti-Ku80 antibodies. Our data suggest that it is necessary to use more than one method to characterize and evaluate autoantibodies in people recovered from COVID-19, in order to avoid misinterpreting those autoantibodies as diagnostic markers for autoimmune diseases.

Positive Autoantibody Is Associated with Malignancies in Patients with Idiopathic Interstitial Pneumonias

Various autoantibodies are associated with clinical outcomes in patients with idiopathic interstitial pneumonias (IIPs). We retrospectively analyzed the association between autoantibodies and malignancies in IIP patients. Comprehensive analyses of autoantibodies were performed using immunoprecipitation and enzyme-linked immunosorbent assays in 193 consecutive IIP patients. Cancer-related factors were analyzed using logistic regression analysis. In total, 22 of 193 patients (11.4%) with IIP had malignant disease. In univariate analysis, positivity for any autoantibody (odds ratio (OR), 3.1; 95% confidence interval (CI), 1.2-7.7; p = 0.017) and antinuclear antibody titer ≥1:320 (OR, 3.4; CI, 1.2-9.8; p = 0.024) were significantly associated with malignancies. Positive anti-aminoacyl tRNA synthetase (ARS) (OR, 3.7; CI, 0.88-15.5; p = 0.074) and anti-Ro52 antibody (OR, 3.2; CI, 0.93-11.2; p = 0.065) tended to be associated with malignancies. In multivariate analysis, independent risk factors were male sex (OR, 3.7; CI, 1.0-13.5; p = 0.029) and positivity for any autoantibody (OR, 3.9; CI, 1.5-10.1; p = 0.004) in model 1, and male sex (OR, 3.9; CI, 1.0-15.3; p = 0.049), antinuclear antibody titer ≥1:320 (OR, 4.2; CI, 1.4-13.3; p = 0.013), and positivity for anti-ARS antibody (OR, 6.5; CI, 1.2-34.1; p = 0.026) in model 2. Positivity for any autoantibody, antinuclear and anti-ARS antibodies, and male sex were independent risk factors for malignancies in IIP patients. Testing autoantibodies in IIP patients might help the early diagnosis of malignancies.

Myositis-specific Antibodies: Overview and Clinical Utilization

Purpose of review-To review autoantibodies associated with different subtypes of idiopathic inflammatory myopathy (IIM) and their clinical applications. IIM are a heterogenous group of autoimmune disorders characterized by muscle weakness, cutaneous features, and internal organ involvement. The diagnosis and classification, which is often challenging, is made using a combination of clinical features, muscle enzyme levels, imaging, and biopsy. The landmark discoveries of novel autoantibodies specific to IIM subtypes have been one of the greatest advancements in the field of myositis. The specificity of these autoantibodies has simplified the diagnostic algorithm of IIM with their heterogenous presentation and outdated the earlier diagnostic criteria. Myositis-specific antibodies (MSAs) have improved diagnostics, clinical phenotyping, and prognostic stratification of the subtypes of IIMs. Furthermore, the levels of certain MSAs correlate with disease activity and muscle enzyme levels such that titers may be able to be used to predict disease course and treatment response.

Prevalent Drug Usage Practices in Adults and Children With Idiopathic Inflammatory Myopathies: Registry-Based Analysis From the MyoCite Cohort

BACKGROUND

Idiopathic inflammatory myopathies (IIMs) form a heterogeneous group of disorders with a deficit of quality evidence regarding its management. Therefore, we aimed to explore the prevalent treatment practices in the MyoCite cohort from India.

METHODS

Drug usage patterns, their predictors, drug retention rates, efficacy, and adverse drug reactions were analyzed for adults and children newly diagnosed with IIM (2017-2020) and followed prospectively and compared with real-world data by performing a medical records review. GraphPad Prism version 8.4.2 was used for statistical analysis.

RESULTS

Of 181 adults (male-to-female ratio, 1:4.6) and 30 children (M:F, 1.3:1), dermatomyositis (41% adults, 93% children) was the most common subtype. Methotrexate (MTX) was the drug of choice (67% adult, 90% children) followed by azathioprine (AZA) and mycophenolate mofetil (MMF). The MMF, AZA, cyclophosphamide, and rituximab (RTX) were preferred for those with antisynthetase syndrome (ASSD) and those with lung involvement, whereas MTX was avoided in them. Functional class and family income did not determine drug preferences. Glucocorticoids were initiated at a lower dose in overlap myositis (45% vs 80%, p = 0.001), and the time to achieve the lowest dose of glucocorticoids was longer than 24 months for ASSD (77% vs 14%, p = 0.002).Over a median of 35 months, the overall retention rate was the highest for RTX (75%) followed by MTX (58%). Relapse-free survival was the highest for RTX followed by MTX. The most common reasons for discontinuation were adverse drug reactions for MTX and MMF, inefficacy for AZA, and cost for RTX.

CONCLUSIONS

In this first analysis of drug usage and retention in patients with IIM in Northern India, MTX emerged as the most preferred drug in both adults and children, with the exception of those with ASSD or lung disease. Organ involvement and subtype of IIM are key determinants of drug preference. Overall, RTX and MTX were well-tolerated with high retention rates, followed by AZA and MMF.

Interstitial pneumonia with autoimmune features: Evaluation of connective tissue disease incidence during follow-up

OBJECTIVES

Among interstitial pneumonia with autoimmune features (IPAF) patients, identifying those at risk to develop a connective tissue disease (CTD) during the disease course is a key issue. The aim of this study was to evaluate the incidence of definite CTD diagnosis in IPAF patients during follow-up.

METHODS

We performed a multicentric cohort study of interstitial lung disease (ILD) from 2010 to 2017 in pneumology and immunology departments of tertiary care centers. Patients with a known cause of ILD (including established CTD) at diagnosis were excluded. Among patients with idiopathic ILD and at least three years of follow-up, two groups (IPAF and non-IPAF) were retrospectively analyzed at time of diagnosis.

RESULTS

A total of 249 patients with ILD were enrolled, including 70 IPAF and 179 non-IPAF patients. After a mean follow-up time of 77 ± 44 months, 18/70 IPAF patients (26%) had a CTD diagnosis - 9 antisynthetase syndrome, 8 systemic sclerosis and 1 overlap myositis - compared with 4/179 non-IPAF patients (2%). IPAF patients were at higher risk of CTD occurrence at 3 years of follow-up compared to non-IPAF patients (HR 10.1, 95% CI 3.1-33.1, p < 0. 01). IPAF patients progressing to CTD tended to be younger, more often female and have more frequently puffy fingers, capillaroscopy abnormalities and antisynthetase antibodies at diagnosis.

CONCLUSIONS

We found that a significant proportion of IPAF patients had associated CTD diagnosis during follow-up. Prospective studies are needed to confirm baseline predictive factors of CTD occurrence in IPAF patients.

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

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

A Comparison of Line Blots, Enzyme-linked Immunosorbent, and RNA-immunoprecipitation Assays of Antisynthetase Antibodies in Serum Samples from 44 Patients

Objective To determine the differences between anti-aminoacyl tRNA synthetase (ARS) antibodies among line blots, enzyme-linked immunosorbent assay (ELISA) anti-ARS tests, and RNA-immunoprecipitation (IP) assays. Methods Sera from patients with confirmed or suspected antisynthetase syndrome (ASS) that were positive for either the anti-ARS test or the line-blot assay were used to perform an RNA-IP assay and ELISA to detect individual anti-ARS antibodies. Results Among the 44 patients, 10 were positive only in line-blot assays, 6 were positive only in the anti-ARS test, and 28 were positive in both assays. We compared the accuracy of these assays against the gold standard RNA-IP assay. The κ coefficient was 0.23 in the line-blot assay, but this increased to 0.75 when the cut-off was increased from 1+ to 2+. The κ coefficient was 0.73 in the anti-ARS test. The κ coefficient was 0.85 for positivity in both assays. Patients with ASS that was positive in an RNA-IP assay more frequently had mechanic's hand (62.1% vs. 20%: p=0.031), myositis (51.7 vs. 10%: p=0.028) and more ASS symptoms than those who were positive only in line-blot assays (3.48 vs. 2.2: p=0.019). Conclusions Clinicians need to understand the features of each assay and determine diagnoses by also considering clinical presentations. Diagnoses should not be judged based only on the results of line-blot assays due to the risk of a misdiagnosis from false positives.

Acute respiratory distress syndrome relapsing in 10 months with an initial manifestation of polymyositis

Autoimmune disorders are an important cause of acute respiratory distress syndrome (ARDS). We report a case of a patient with steroid-responsive ARDS that relapsed in 10 months with an initial manifestation of seronegative polymyositis. ARDS associated with polymyositis may develop earlier than myopathy and may relapse later.

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.

Diagnosis of myositis-associated interstitial lung disease: Utility of the myositis autoantibody line immunoassay

OBJECTIVES

The detection of myositis autoantibodies (MA) in patients with interstitial lung disease (ILD) has major implications for diagnosis and management, especially amyopathic and forme frustes of idiopathic inflammatory myositis-associated ILD (IIM-ILD). Use of the MA line immunoblot assay (MA-LIA) in non-rheumatological cohorts remains unvalidated. We assessed the diagnostic performance of the MA-LIA and explored combined models with clinical variables to improve identification of patients with IIM-ILD.

METHODS

Consecutive patients referred to a specialist ILD clinic, with ILD-diagnosis confirmed at multidisciplinary meeting, and MA-LIA performed within six months of baseline were included. Pre-specified MA-LIA thresholds were evaluated for IIM-ILD diagnosis.

RESULTS

A total 247 ILD patients were included (IIM-ILD n = 12, non-IIM connective tissue disease-associated ILD [CTD-ILD] n = 52, idiopathic interstitial pneumonia [IIP] n = 115, other-ILD n = 68). Mean age was 64.8 years, with 45.3% female, mean FVC 75.5% and DLCO 59.2% predicted. MA were present in 13.8% overall and 83.3% of IIM-ILD patients. The most common MA in IIM-ILD and non-IIM ILD patients were anti-Jo-1 (prevalence 40%) and anti-PMScl (29.2%) autoantibodies respectively. The pre-specified low-positive threshold (>10 signal intensity) had the highest discriminative capacity for IIM-ILD (AUC 0.86). Combining MA-LIA with age, gender, clinical CTD-manifestations and an overlap non-specific interstitial pneumonia/organising pneumonia pattern on HRCT improved discrimination for IIM-ILD (AUC 0.96).

CONCLUSION

The MA-LIA is useful to support a diagnosis of IIM-ILD as a complement to multi-disciplinary ILD assessment. Clinical interpretation is optimised by consideration of the strength of the MA-LIA result together with clinical and radiological features of IIM-ILD.

High-Resolution CT Findings of Myositis-Related Interstitial Lung Disease

Myositis-related interstitial lung disease presents with a wide variety of lesions, ranging from chronic to acute. It can be divided into two main forms by the types of onsets, namely, chronic to subacute type showing nonspecific interstitial pneumonia (NSIP) or NSIP with an organizing pneumonia (OP)/fibrosing OP (FOP) pattern and acute type showing acute lung injury (ALI) to diffuse alveolar damage (DAD) pattern. Anti-aminoacyl tRNA Synthetase antibody-positive cases mainly show an NSIP or FOP pattern, whereas anti-melanoma differentiation-associated gene 5 antibody-positive cases show ALI to DAD pattern. Bilateral consolidation with or without ground-glass opacification with lower lobe predominance is common as a major pattern in all types, but the distribution or extent is sometimes different. The early detection of findings that indicate a rapid progressive course is vital. Diffuse cranio-caudal distribution and multiple ground-glass opacifications with random distribution might indicate a poorer prognosis.

Myositis-Related Interstitial Lung Disease: A Respiratory Physician's Point of View

Idiopathic inflammatory myositis (IIM) is an umbrella term for diseases of unknown origin that cause muscle inflammation. Dermatomyositis and polymyositis are IIMs that commonly cause interstitial lung disease (ILD). When a patient presents with ILD, the evaluation of whether the case displays the characteristics of myositis should be determined by interview, physical examination, imaging findings, the measurement of myositis-related antibodies, and the determination of disease severity after diagnosis. Rapidly progressing anti-melanoma differentiation-associated gene 5 antibody-positive ILD may require rapid multi-drug therapy, while anti-aminoacyl tRNA synthetase (ARS) antibody-positive ILD can be treated with anti-inflammatory drugs. Importantly, however, anti-ARS antibody-positive ILD often recurs and sometimes develops into fibrosis. Early diagnosis is crucial for treatment, and we therefore need to clarify the features of myositis associated with ILD and suspect these pathologies early. This section reviews what clinicians need to look for and what findings are evaluated in patients when diagnosing myositis associated with ILD.

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.

EGFR-mutant lung adenocarcinoma associated with antisynthetase syndrome successfully treated with osimertinib

Here, we report a rare case involving a 66-year-old man with epidermal growth factor receptor (EGFR)-mutant lung adenocarcinoma and antisynthetase syndrome (ASS) treated with osimertinib. The patient presented with respiratory failure and bilateral pulmonary opacities; he was diagnosed with ASS accompanied by interstitial lung disease (ILD), consistent with paraneoplastic syndrome. After steroid pulse therapy, osimertinib was administered for lung adenocarcinoma without ILD exacerbation. Osimertinib could therefore be a treatment option for EGFR-mutant lung cancer with paraneoplastic ILD.

Clinical features of anti-synthetase syndrome associated interstitial lung disease: a retrospective cohort in China

Background

Anti-synthetase syndrome (ASSD) is a chronic autoimmune condition characterized by antibodies directed against an aminoacycl transfer RNA synthetase (ARS) along with a group of clinical features including the classical clinical triad: inflammatory myopathy, arthritis, and interstitial lung disease (ILD). ASSD is highly heterogenous due to different organ involvement, and ILD is the main cause of mortality and function loss, which presents as different patterns when diagnosed. We designed this retrospective cohort to describe the clinical features and disease behaviour of ASSD associated ILD.

Methods

Data of 108 cases of ASSD associated ILD were retrospectively collected in Beijing Chaoyang Hospital from December 2017 to March 2019. Data were obtained from the Electronic Medical Record system. Patients were divided into 5 groups according to distinct aminoacyl tRNA synthetase (ARS) antibodies.

Results

Overall, 108 consecutive patients were recruited. 33 were JO-1 positive, 30 were PL-7 positive, 23 were EJ positive, 13 were PL-12 positive and 9 were OJ positive. The JO-1 (+) group had a significant higher rate of mechanic’s hand (57.6%) than other 4 groups. Polymyositis/dermatomyositis (PM/DM) was diagnosed in 25 (23.1%) patients and no difference was observed among the 5 groups. The PL-7 (+) group had a higher frequency of UIP pattern (13.3%) than the other 4 groups but the difference was not significant, and the EJ (+) group had the most frequent OP pattern (78.2%), which was significantly higher than the PL-7 (+) (P < 0.001) and PL-12 (+) groups (P = 0.025). The median follow-up time was 10.7 months, during which no patients died. All received prednisone treatment, with or without immunosuppressants. At the 6-month follow-up, 96.3% of all patients (104/108) had a positive response to therapy, the JO-1 (+) and EJ (+) groups had a significantly higher improvement of forced vital capacity than the other 3 groups (P < 0.05), and the PL-7 group had the lowest FVC improvement (P < 0.05). The JO-1 (+) group and EJ (+) group had significantly higher anti-Ro-52 positive occurrence than the other 3 groups (P < 0.05).

Conclusion

Anti PL-7 antibody had the same frequency as anti-JO-1 in ASSD-ILD, in which the ILD pattern was different with distinct anti-ARS antibodies. Most ASSD-ILD had a positive response to steroid therapies, with or without immunosuppressants. The PL-7 (+) group had the highest occurrence of UIP pattern, and a significantly lower response to therapy.

The uniqueness of AlaRS and its human disease connections

Among the 20 cytoplasmic aminoacyl-tRNA synthetases (aaRSs), alanyl-tRNA synthetase (AlaRS) has unique features. AlaRS is the only aaRS that exclusively recognizes a single G3:U70 wobble base pair in the acceptor stem of tRNA, which serves as the identity element for both the synthetic and the proofreading activities of the synthetase. The recognition is relaxed during evolution and eukaryotic AlaRS can mis-aminoacylate noncognate tRNAs with a G4:U69 base pair seemingly as a deliberate gain of function for unknown reasons. Unlike other class II aaRSs, dimerization of AlaRS is not necessarily required for aminoacylation possibly due to functional compensations from the C-terminal domain (C-Ala). In contrast to other 19 cytoplasmic aaRSs that append additional domains or motifs to acquire new functions during evolution, the functional expansion of AlaRS is likely achieved through transformations of the existing C-Ala. Given both essential canonical and diverse non-canonical roles of AlaRS, dysfunction of AlaRS leads to neurodegenerative disorders in human and various pathological phenotypes in mouse models. In this review, the uniqueness of AlaRS in both physiological and pathological events is systematically discussed, with a particular focus on its novel functions gained in evolution.

Prednisolone and tacrolimus versus prednisolone and cyclosporin A to treat polymyositis/dermatomyositis-associated ILD: A randomized, open-label trial

BACKGROUND AND OBJECTIVE

The efficacy of combination therapy with corticosteroids and CNI, TAC and CsA, for PM/DM-ILD has been described retrospectively. However, it remains unknown which CNI treatment regimens, TAC or CsA regimens, are more effective as initial treatments for patients with PM/DM-ILD.

METHODS

We conducted a prospective multicentre, open-label, randomized, 52-week phase 2 trial. Patients with PM/DM-ILD were randomly allocated to receive PSL plus TAC (TAC group) or PSL plus CsA (CsA group). The primary endpoint was PFS rate in the intention-to-treat population at 52 weeks. The secondary endpoints were OS rate at 52 weeks, changes in pulmonary function tests from baseline to 52 weeks and AE.

RESULTS

Fifty-eight patients were randomly assigned to the TAC group (n = 30) and the CsA group (n = 28). The PFS rates at 52 weeks were 87% in the TAC group and 71% in the CsA group (P = 0.16). The OS rates at 52 weeks were 97% in the TAC group and 93% in the CsA group (P = 0.50). The %FVC at 52 weeks in the per-protocol populations significantly increased in both groups. None of the patients discontinued the treatment due to AE.

CONCLUSION

PSL plus TAC treatment may achieve a better short-term PFS rate compared with PSL plus CsA treatment. Further studies must be conducted to evaluate the long-term efficacy and safety of such treatment.

Mizoribine treatment in an elderly diabetic patient with antisynthetase-associated interstitial lung disease

Objective: Immunosuppressive therapy for interstitial lung disease (ILD) is often necessary, but the standard regimen for antisynthetase-associated ILD has not been established.

Patient: An 80-year-old man was hospitalized for severely progressive dyspnea. Bilateral interstitial shadows occurred 1 month before the event. Serological findings showed that he had antisynthetase-associated ILD, as identified by strong positivity for anti-aminoacyl-transfer RNA synthetase (ARS) antibody, despite no evidence of myositis. He was treated transiently with noninvasive positive pressure ventilation and steroid-pulse therapy followed by 60 mg/day of oral prednisolone. However, his diabetes mellitus was aggravated by corticosteroid therapy; thus, a combination of low-dose steroid and mizoribine (MZB), which has a low risk of aggravating glucose intolerance, was used.

Results: The patient’s clinical symptoms and daily life activities have been well persevered as an outpatient and well maintained with 200 mg of MZB and 10 mg of prednisolone for several months without obvious clinical recurrence and without any remarkable steroid- and MZB-related side effects.

Conclusion: The use of MZB appeared to suppress the pathophysiology of anti-ARS antibody-associated ILD.

A case with overlapping features of IgG4-related autoimmune pancreatitis, Sjögren's syndrome and anti-aminoacyl-tRNA synthetase syndrome

A 55-year-old man who had been diagnosed with autoimmune pancreatitis five years earlier was referred to our department because of finger swelling, finger stiffness and the presence of interstitial lung disease (ILD). The patient was diagnosed with Sjögren's syndrome according to the pathological findings of minor salivary glands and positive anti-SS-A antibodies. Later, at age 58, he was hospitalised due to the exacerbation of the ILD. Serum IgG4 level was checked and was found to be elevated (417 mg/dL). After the introduction of cyclosporine in addition to the prednisolone, at age 60, the ILD disease activity stabilised. However, at age 62, fever, myalgia and mechanic's hands appeared. His serum creatine kinase level was high, and magnetic resonance imaging showed inflammatory findings of muscle. In-house ELISA clarified that his serum carried anti-PL-7 antibody among anti-aminoacyl-tRNA synthetase antibodies. This is a unique case who had overlapping features of IgG4-related autoimmune pancreatitis, Sjögren's syndrome and anti-synthetase syndrome. Although the aetiology of the complications in this patient is obscure, autoimmunity might have played a significant role in the disease conditions and prognosis of the present case with IgG4-related disease.

Revisiting Cell Death Responses in Fibrotic Lung Disease: Crosstalk between Structured and Non-Structured Cells

Fibrosis is a life-threatening disorder caused by excessive formation of connective tissue that can affect several critical organs. Innate immune cells are involved in the development of various disorders, including lung fibrosis. To date, several hematopoietic cell types have been implicated in fibrosis, including pro-fibrotic monocytes like fibrocytes and segregated-nucleus-containing atypical monocytes (SatMs), but the precise cellular and molecular mechanisms underlying its development remain unclear. Repetitive injury and subsequent cell death response are triggering events for lung fibrosis development. Crosstalk between lung structured and non-structured cells is known to regulate the key molecular event. We recently reported that RNA-binding motif protein 7 (RBM7) expression is highly upregulated in the fibrotic lung and plays fundamental roles in fibrosis development. RBM7 regulates nuclear degradation of NEAT1 non-coding RNA, resulting in sustained apoptosis in the lung epithelium and fibrosis. Apoptotic epithelial cells produce CXCL12, which leads to the recruitment of pro-fibrotic monocytes. Apoptosis is also the main source of autoantigens. Recent studies have revealed important functions for natural autoantibodies that react with specific sets of self-antigens and are unique to individual diseases. Here, we review recent insights into lung fibrosis development in association with crosstalk between structured cells like lung epithelial cells and non-structured cells like migrating immune cells, and discuss their relevance to acquired immunity through natural autoantibody production.

Predictive factors for the recurrence of anti-aminoacyl-tRNA synthetase antibody-associated interstitial lung disease

BACKGROUND

Anti-synthetase syndrome (ASS) is characterized by the presence of anti-aminoacyl-tRNA synthetase antibody and ASS-associated interstitial lung disease (ILD) often recurs. The effectiveness of remission induction therapy with corticosteroids and calcineurin inhibitor (CNI) and the predictive factors for ASS-ILD recurrence were examined.

METHODS

We retrospectively identified consecutive patients with ASS-ILD treated with corticosteroids and CNI during 2006-2017 and evaluated the predictive factors for recurrence using logistic regression analysis.

RESULTS

Of the 57 patients included in this study, 54 (94.7%) exhibited improved response to remission induction therapy. There were 32 recurrence patients during maintenance therapy. The median period until recurrence was 27 months. There were no significant differences in the baseline characteristics between the recurrence and nonrecurrence groups. In the recurrence group, respiratory function and St. George's Respiratory Questionnaire score deteriorated over the clinical course. The Krebs von den Lungen-6 (KL-6) level changed with disease behavior. The multivariate analysis revealed that KL-6 increase rate from remission (odds ratio: 3.21, 95% CI: 1.17-8.86, p = 0.02) and CNI discontinuation (odds ratio: 8.09, 95% CI: 1.39-47.09, p = 0.02) were independent predictive factors for recurrence. The receiver operating characteristics analysis revealed that the optimal cut-off point of KL-6 increase rate was 2.0. The positive predictive values of the KL-6 increase rate from remission of >2.0 and CNI discontinuation were 90.0 and 88.9%, respectively. The CNI treatment duration and recurrence were not related.

CONCLUSIONS

Recurrence influenced long-term deterioration. KL-6 was a serum biomarker for disease behavior and recurrence prediction. The results suggest the importance of CNI continuation.

The clinical phenotype associated with antisynthetase autoantibodies

OBJECTIVES

Specific systemic autoimmune syndrome characterized by inflammatory myopathy, arthritis or arthralgias, interstitial lung disease (ILD), fever, Raynaud's phenomenon, and mechanic's hands is called antisynthetase syndrome (AS). The aim of this study was to assess the clinical spectrum associated with presence of aminoacyl-transfer RNA synthetase autoantibodies (ASA).

MATERIAL AND METHODS

A total of 305 patients with presence of myositis-specific autoantibodies were identified in the database of immunological tests performed in the Clinical Immunology and Transplantology Unit, Medical University of Gdansk between January 2011 and March 2016. In 110 patients (36%) ASA were detected. The detailed analysis included 50 patients with ASA for whom full clinical data were available.

RESULTS

The incidence of specific ASA in the analyzed group was: Jo-1 46% (23 patients), PL-12 32% (16 patients), PL-7 16% (8 patients), OJ 12% (6 patients), EJ 6% (3 patients). In 10% (5 patients) there was coexistence of at least one ASA, and in another 5 patients there was coexistence of ASA with other antibodies specific for myositis (MSA). In the analyzed group of patients 11 (22%) satisfied the Bohan and Peter criteria for dermatomyositis, 1 for polymyositis. In 5 patients (10%) based on clinical presentation and ASA presence the AS was recognized. Another 3 patients met the criteria of the overlap syndrome polymyositis respectively with systemic lupus, rheumatoid arthritis, and scleroderma. In 5 patients undifferentiated connective tissue disease was diagnosed, and 14 consecutive patients were diagnosed with other connective tissue diseases, while 12 patients did not receive a definitive diagnosis.

CONCLUSIONS

The clinical presentation of patients with the presence of ASA is varied. Their presence indicates not only idiopathic inflammatory myopathies, but also non-specifically other disease entities. These patients require observation for the development of idiopathic inflammatory myopathy, and ILD.

Combined immunosuppressive therapy provides favorable prognosis and increased risk of cytomegalovirus reactivation in anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody (Ab) is myositis-specific autoantibody associated with rapidly progressive interstitial lung disease (ILD) and poor prognosis. In this retrospective observational study, we aimed to verify the efficacy and safety of introducing combined immunosuppressive therapy for anti-MDA5 Ab-positive dermatomyositis (DM) from their early stage. We recruited all Japanese patients diagnosed with DM in our clinic between January 2011 and October 2018, who had anti-MDA5 Ab, anti-aminoacyl transfer RNA synthetase Ab or anti-transcriptional intermediary factor 1-γ Ab. Combined immunosuppressive therapy was defined as combination of systemic corticosteroids, i.v. cyclophosphamide and tacrolimus. The difference of clinical features among the three groups was analyzed by multiple comparison analysis. The longitudinal change of the measurements from baseline was examined by Wilcoxon signed-rank test. Association between therapeutic regimens and adverse events was examined by logistic regression analysis. As a result, combined immunosuppressive therapy was most frequently used in the anti-MDA5 Ab-positive group, which significantly improved their forced vital capacity of the lung. Interval time since initial visit until starting treatment was the shortest in the anti-MDA5 Ab-positive group. There was no significant difference in the incidence of death and recurrence among the three groups. Cytomegalovirus reactivation was most common in the anti-MDA5 Ab-positive group, associated with combined immunosuppressive therapy. Collectively, early introduction of combined immunosuppressive therapy was effective for DM patients with anti-MDA5 Ab. At the same time, clinicians should be aware of the risk of cytomegalovirus reactivation during the treatment.

Usefulness of serum Krebs von den Lungen-6 for the management of myositis-associated interstitial lung disease

OBJECTIVE

To identify biomarkers for assessing myositis-associated interstitial lung disease (ILD).

METHODS

We reviewed consecutive patients from our institution who had been newly diagnosed with PM, DM, or clinically amyopathic DM during the years 2002-2017. The patients were divided into two groups according to the presence of ILD, and the ILD group was further subdivided into three groups according to the clinical courses of induction failure, relapse and non-relapse. Baseline and time-course changes in the parameters were compared between groups.

RESULTS

Among 110 patients enrolled, 75 (68%) had ILD. Baseline serum Krebs von den Lungen-6 (KL-6) was significantly higher in the ILD group than in the non-ILD group (1120 vs 236 U/ml; P < 0.001). In the ILD group consisting of the induction failure cases (n = 3), the relapse group (n = 24) and the non-relapse group (n = 48), baseline serum KL-6 was significantly different between the three groups [1971 vs 1870 vs 935 U/ml, respectively; P = 0.003 (relapse group vs non-relapse group)]. The time-course changes in serum KL-6 revealed that KL-6 significantly increased along with relapse, with the increase of 625 U/ml relevant to relapse.

CONCLUSION

Serum KL-6 is a useful biomarker for assessing the disease activity of myositis-associated ILD.

Natural Autoantibodies in Chronic Pulmonary Diseases

In autoantibody-mediated autoimmune diseases, pathogenic autoantibodies generated by a failure of central or peripheral tolerance, have different effects mediated by a variety of mechanisms. Interestingly, even non-autoimmune chronic diseases have a set of disease-specific natural autoantibodies that are maintained for a long time. Because most of these natural autoantibodies target intracellular proteins or long non-coding RNAs, they are speculated to be non-pathological and have some important as yet unrecognized physiological functions such as debris clearance. Recently, we revealed a set of disease-specific natural autoantibodies of chronic pulmonary diseases with unknown etiology by protein arrays that enable detection of specific autoantibodies against >8000 targets. Surprisingly, some of the targeted antigens of disease-specific autoantibodies were subsequently reported by other laboratories as strongly associated with the disease, suggesting that these antigens reflect the pathology of each disease. Furthermore, some of these autoantibodies that target extracellular antigens might modify the original course of each disease. Here, we review the disease-specific natural autoantibodies of chronic pulmonary diseases, including chronic fibrosing idiopathic interstitial pneumonias, sarcoidosis, and autoimmune pulmonary alveolar proteinosis, and discuss their utility and effects.

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.

Acute lung injury after plasma exchange in a patient with anti-MDA5 antibody-positive, rapidly progressive, interstitial lung disease：A case report

The presence of anti-melanoma differentiation-associated gene 5 antibody (anti-MDA5 Ab) is closely associated with rapidly progressive interstitial lung disease (RP-ILD) in patients with clinically amyopathic dermatomyositis. Despite intensive immunosuppressive therapies, some of these patients still have a poor prognosis with few treatment options. Although removal of pathogenic autoantibodies and cytokines by plasma exchange (PE) could be a treatment option, its safety and efficacy have never been determined. We report a patient with anti-MDA5 Ab-positive RP-ILD who was refractory to intensive therapies including steroids, cyclosporine, and intravenous cyclophosphamide, and then treated by PE to prevent the progression of RP-ILD. Shortly after the initiation of PE therapy, however, his respiratory condition suddenly deteriorated due to acute pulmonary edema and the patient died on the following day. Transfusion-related acute lung injury (TRALI) would be the most likely cause of the acute pulmonary edema because there was no sign of circulatory overload. To the best of our knowledge, this is the first report showing a critical adverse event associated with PE therapy for these patients. This case supports the idea that the presence of ILD could increase a risk for TRALI and therefore we should carefully evaluate the eligibility for PE therapy of anti-MDA5 Ab-positive RP-ILD patients given the risk of acute lung injury. Further studies collecting more clinical data are necessary to assess the efficacy, safety, and risk factors of PE therapy for these patients.

Successful treatment of thymic carcinoma with dermatomyositis and interstitial pneumonia: A case report

Here, we report a rare case of thymic carcinoma (TC) associated with dermatomyositis (DM) and interstitial pneumonia (IP) in a 68-year-old man. The patient presented with the characteristic features of a skin rash with Gottron's papules and increased serum levels of muscle-associated enzymes. Computed tomography (CT) showed the presence of an anterior mediastinal soft tissue mass with IP, which was diagnosed as TC by CT-guided tumor biopsy. The patients DM and IP disappeared completely after radical resection of the tumor. After a 20-month follow-up period, the patient was in good clinical condition without disease recidivism.

Korean Guidelines for Diagnosis and Management of Interstitial Lung Diseases: Part 5. Connective Tissue Disease Associated Interstitial Lung Disease

Connective tissue disease (CTD) is a collection of disorders characterized by various signs and symptoms such as circulation of autoantibodies in the entire system causing damage to internal organs. Interstitial lung disease (ILD) which is associated with CTD is referred to as CTD-ILD. Patients diagnosed with ILD should be thoroughly examined for the co-occurrence of CTD, since the treatment procedures and prognosis of CTD-ILD are vary from those of idiopathic interstitial pneumonia. The representative types of CTD which may accompany ILD include rheumatoid arthritis, systemic sclerosis (SSc), Sjögren's syndrome, mixed CTD, idiopathic inflammatory myopathies, and systemic lupus erythematous. Of these, ILD most frequently co-exists with SSc. If an ILD is observed in the chest, high resolution computed tomography and specific diagnostic criteria for any type of CTD are met, then a diagnosis of CTD-ILD is made. It is challenging to conduct a properly designed randomized study on CTD-ILD, due to low incidence. Therefore, CTD-ILD treatment approach is yet to been established in absence of randomized controlled clinical trials, with the exception of SSc-ILD. When a patient is presented with acute CTD-ILD or if symptoms occur due to progression of the disease, steroid and immunosuppressive therapy are generally considered.

Serum matrix metalloproteinase levels in polymyositis/dermatomyositis patients with interstitial lung disease

OBJECTIVE

We aimed to clarify the clinical significance of serum levels of MMPs in interstitial lung disease (ILD) complicated with PM/DM (PM/DM-ILD).

METHODS

We retrospectively analysed serum levels of seven subsets of MMPs in 52 PM/DM-ILD patients diagnosed at Kyoto University Hospital or Tenri Hospital from January 2005 to December 2014. The patients were sub-grouped based on the presence of anti-amimoacyl-tRNA synthetase antibody (anti-ARS antibody), anti-melanoma differentiation-associated protein 5 antibody (anti-MDA5 antibody) or lack of the antibodies (ARS-ILD, MDA5-ILD and other-ILD groups, respectively) and independently analysed. Eighteen PM/DM patients without ILD and 55 healthy control were also analysed. Associations between serum levels of MMPs and clinical findings including mortality were analysed.

RESULTS

Among the MMPs analysed, MMP-7 serum levels in the ARS-ILD group were significantly higher compared with those in any of the other groups of PM/DM patients or in healthy controls. On the other hand, in the MDA5-ILD group, serum MMP-7 levels >5.08 ng/ml were associated with worse overall survival both in univariate (P = 0.017; odds ratio 18.0; 95% CI 1.69, 192.00) and multivariate (P = 0.027; odds ratio 14.60; 95% CI 1.11, 192.00) analyses. Immunohistochemical analysis suggested that MMP-7 was expressed in type II alveolar epithelial cells adjacent to the fibrotic lesions.

CONCLUSION

Serum MMP-7 levels were higher in anti-ARS antibody-positive PM/DM-ILD patients, while higher serum MMP-7 levels among anti-MDA5 antibody-positive PM/DM-ILD patients were associated with a worse prognosis. Fibrotic processes may be associated with the elevation of serum MMP-7 levels.

Efficacy of Glucocorticoids and Calcineurin Inhibitors for Anti-aminoacyl-tRNA Synthetase Antibody–positive Polymyositis/dermatomyositis–associated Interstitial Lung Disease: A Propensity Score–matched Analysis

Objective.

The optimal treatment strategy for anti-aminoacyl-tRNA synthetase antibody–positive polymyositis/dermatomyositis-associated interstitial lung disease (anti-ARS-PM/DM-ILD) is yet to be established. We aimed to evaluate the efficacy of glucocorticoids and calcineurin inhibitors (CNI) in patients with ARS-PM/DM-ILD.

Methods.

Progression-free survival (PFS) and overall survival rates were retrospectively evaluated in 32 consecutive patients with ARS-PM/DM-ILD. Disease progression was defined as deterioration in PM/DM-ILD (including recurrence). Predictive factors associated with PFS were analyzed by Cox hazards analysis. The efficacy of first-line prednisolone (PSL) plus CNI therapy was compared with that of PSL monotherapy using propensity score–matched analysis.

Results.

Overall, 20 (62.5%) and 12 (37.5%) patients received first-line therapy with PSL + CNI and PSL, respectively. The 2-year PFS and 5-year survival rates in the overall cohort were 68.8% and 96.9%, respectively. On multivariate analysis, arterial oxygen pressure (HR 0.86) and PSL monotherapy (vs PSL + CNI; HR 7.29) showed an independent association with PFS. Baseline characteristics of propensity score-matched PSL + CNI and PSL groups were similar. The 2-year PFS rate was significantly higher in the matched PSL + CNI group than in the matched PSL group. All patients who experienced disease progression during first-line therapy were subsequently treated with second-line therapies. The 5-year survival rates of both the matched PSL + CNI and PSL groups were favorable.

Conclusion.

Propensity score–matched analysis demonstrated that first-line PSL + CNI therapy for patients with ARS-PM/DM-ILD significantly improved the PFS compared with PSL monotherapy, although there was no significant difference regarding longterm survival.

Recent Advances in Research Regarding Autoantibodies in Connective Tissue Diseases and Related Disorders

Connective tissue diseases (CTDs), also known as systemic autoimmune diseases, involve a variety of autoantibodies against cellular components. An important factor regarding these autoantibodies is that each antibody is exclusively related to a certain clinical feature of the disease type, which may prove useful in clinical practice. Thus far, more than 100 types of autoantibodies have been found in CTDs, and most of their target antigens have been identified. Many of these autoantigens are enzymes or regulators involved in important cellular functions, such as gene replication, transcription, repair/recombination, RNA processing, and protein synthesis, as well as proteins that form complexes with RNA and DNA. This article reviews the autoantibodies for each CTD, along with an assessment of their clinical significance, and provides suggestions regarding their utilization for clinical practice.

Treatment consensus for management of polymyositis and dermatomyositis among rheumatologists, neurologists and dermatologists

Although rheumatologists, neurologists and dermatologists see patients with polymyositis (PM) and dermatomyositis (DM), their management appears to vary depending on the physician's specialty. The aim of the present study was to establish the treatment consensus among specialists of the three fields to standardize the patient care. We formed a research team supported by a grant from the Ministry of Health, Labor and Welfare, Japan. Clinical questions (CQ) on the management of PM and DM were raised. A published work search on CQ was performed primarily using PubMed. Using the nominal group technique, qualified studies and results in the published work were evaluated and discussed to reach consensus recommendations. They were sent out to the Japan College of Rheumatology, Japanese Society of Neurology and Japanese Dermatological Association for their approval. We reached a consensus in 23 CQ and made recommendations and a decision tree for management was proposed. They were officially approved by the three scientific societies. In conclusion, a multidisciplinary treatment consensus for the management of PM and DM was established for the first time.

Serial measurements of KL-6 for monitoring activity and recurrence of interstitial pneumonia with anti-aminoacyl-tRNA synthetase antibody: A retrospective cohort study

The aim of this study was to evaluate whether serial measurements of serum Krebs von den Lungen-6 (KL-6) could be used to monitor disease activity and to detect recurrence in patients with interstitial pneumonia (IP) with anti-aminoacyl-tRNA synthetase antibodies (ARS-IP).This retrospective cohort study included 44 patients with ARS-IP. Thirty-six patients had serial data of blood tests and pulmonary function tests. Baseline and longitudinal analyses were performed to investigate whether lung function parameters were associated with serum biomarkers (KL-6, lactate dehydrogenase [LDH], and C-reactive protein [CRP]) using Pearson correlation coefficient. Additionally, the diagnostic accuracy of changes in these biomarkers for detecting ARS-IP recurrence was analyzed by receiver operating characteristic curve analysis.Baseline levels of serum KL-6 were significantly associated with vital capacity (VC) and diffusion capacity for carbon monoxide (DLco) (r = -0.40, P = .015, and r = -0.44, P = .010, respectively). Longitudinal changes in KL-6 were inversely correlated with changes in VC and DLco (r = -0.57, P <.001 and r = -0.42, P <.001, respectively), whereas those in LDH and CRP were not. Moreover, longitudinal changes in serum KL-6 were significantly associated with recurrence of ARS-IP and could be used to detect ARS-IP recurrence; the area under the curve was 0.79 (P = .002).The present study demonstrated that serial measurement of KL-6 is useful for monitoring disease activity and detecting recurrence of ARS-IP.

Clinical significance of myositis-specific autoantibodies

To date, increasing numbers of myositis-specific autoantibodies (MSAs) have been reported and their clinical significance has been elucidated. Anti-aminoacyl-tRNA synthetase (ARS) and anti-melanoma-differentiation associated gene 5 (MDA5) are strongly associated with interstitial lung disease (ILD); however, the clinical course of ILD is different depending on which autoantibody is present. Anti-ARS is associated with chronic and repetitive ILD and anti-MDA5 is associated with rapidly progressive ILD. Anti-MDA5, anti-transcriptional intermediary factor (TIF) 1-γ, anti-nuclear matrix protein (NXP) 2 and anti-Mi-2 antibodies are dermatomyositis specific. Anti-TIF1-γ and anti-NXP-2 antibodies are associated with malignancy, and anti-signal recognition particle (SRP) and anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) antibodies are associated with immune-mediated necrotizing myopathy (IMNM). Prognosis is also different among MSA-positive patient groups. Thus, MSAs are of great use for predicting disease course, prognosis, and determining therapeutic strategy as well as the diagnosis of idiopathic inflammatory myopathy (IIM) patients. Investigation of the pathogenic role of MSAs and their corresponding autoantigens will help us to understand the pathophysiology of IIM and identify new therapeutic targets.

Anti-PL-7 Antisynthetase Syndrome with Eosinophilic Pleural Effusion

A 68-year-old woman was admitted to our hospital with fever and pleural effusion. Her thoracentesis showed eosinophilic pleural effusion (EPE) without any evidence of malignancy, infection, or trauma. Pleural biopsy revealed pleuritis and intercostal myositis. Characteristic skin manifestations, including Gottron's sign, interstitial lung disease, and pericardial effusion, appeared later in the clinical course. She was finally diagnosed with anti-PL-7 antisynthetase syndrome (ASS) based on the presence of anti-PL-7 antibody, and she fulfilled the diagnostic criteria for dermatomyositis. These clinical manifestations improved with immunosuppressive therapy. EPE might therefore be one of the characteristic features of anti-PL-7 ASS.

Serum levels of B-cell activating factor of the TNF family (BAFF) correlate with anti-Jo-1 autoantibodies levels and disease activity in patients with anti-Jo-1positive polymyositis and dermatomyositis

BACKGROUND

B-cell activating factor of the tumour necrosis factor family (BAFF) plays a role in autoantibody production and is elevated in dermatomyositis (DM) and anti-Jo-1-positive polymyositis (PM). We investigated the inter-relationships between serum levels of BAFF, anti-Jo-1 autoantibodies, and disease activity.

METHODS

Serum levels of BAFF and anti-Jo-1 antibodies measured by enzyme-linked immunosorbent assay (ELISA) were compared to levels of myoglobin, creatine kinase (CK), aminotransferases (alanine (ALT) and aspartate (AST)), C-reactive protein (CRP), and disease activity assessed by the Myositis Disease Activity Assessment Tool in 63 anti-Jo-1 antibody-positive DM/PM patients. Serial serum samples collected at 2 (46 cases) and 3-5 time points (23 cases) were included. Relationships between BAFF, anti-Jo-1, disease activity, CRP, and their longitudinal changes were evaluated using correlation analysis, multiple regression (MR), path analysis (PA), and hierarchical linear models (HLM).

RESULTS

Cross-sectional assessment demonstrated significant correlations between the levels of BAFF and anti-Jo-1 antibodies which were associated with levels of CK, myoglobin, AST, and CRP, as well as multivariate associations between BAFF, anti-Jo-1 antibodies, and CK levels. PA revealed direct effects of anti-Jo-1 antibodies on CK (β = 0.41) and both direct (β = 0.42) and indirect (through anti-Jo-1 antibodies; β = 0.17) effects of BAFF on CK. Changes in levels of both BAFF and anti-Jo-1 between two time points (Δ) were associated with Δmyoglobin and Δaminotransferases and changes of BAFF correlated with ΔCK, Δcutaneous, Δmuscle, Δglobal, and Δskeletal disease activities. The longitudinal analysis showed a high intra-individual variability of serum levels of BAFF over time (97%) which could predict 79% of the variance in anti-Jo-1 levels. The anti-Jo-1 variability was explained by inter-individual differences (68%). The close longitudinal relationship between levels of BAFF, anti-Jo-1, and disease activity was supported by high proportions of their variance explained with serum levels of CK and CRP or pulmonary and muscle activities.

CONCLUSION

Our findings of associations between levels of BAFF and anti-Jo-1 antibodies in serum and myositis activity suggest a role of this cytokine in disease-specific autoantibody production as part of disease mechanisms, and support BAFF as a potential target for intervention in anti-Jo-1-positive myositis patients.