Ro52, Myositis, and Interstitial Lung Disease

Janus kinase inhibition (JAKi) therapy in refractory anti-synthetase syndrome: A retrospective cohort study

OBJECTIVES

To evaluate the efficacy and safety of Janus kinase inhibitors (JAKi) in the treatment of refractory anti-synthetase syndrome (ASS) in real-world clinical settings.

METHODS

The medical records of all refractory ASS patients who were treated with JAKi from October 2020 to June 2023 were retrospectively reviewed.

RESULTS

Twenty patients were included, and all (100 %) patients had interstitial lung disease (ILD). After treatment with JAKi, 14 (70 %) of the refractory ASS patients showed significant improvement in clinical manifestations, including arthritis (56.3 % vs. 6.3 %, p = 0.002), rash (77.8 % vs. 27.8 %, p = 0.012), shortness of breath (55.6 % vs. 16.7 %, p = 0.039), cough (61.1 % vs. 11.1 %, p = 0.012). Improvement was noted for myalgia (50 % vs. 11.1 %, p = 0.016) and muscular weakness (61.1 % vs. 11.1 %, p = 0.012), while creatine kinase (CK) levels, which were abnormally elevated in five patients prior treatment, were significantly lowered (1096 ± 1042.98 IU/L vs. 199.2 ± 144.66 IU/L, p = 0.043). A decrease in levels of inflammatory markers, including erythrocyte sedimentation rate (ESR) (p = 0.001) and C-reactive protein (CRP) (p = 0.023) was observed in the patients. In ASS-ILD, the CT score reduced (188.75 ± 69.67 vs. 156.35 ± 74.62, p = 0.001). Furthermore, the glucocorticoid dose significantly reduced (21.42 ± 13.26 mg vs. 11.32 ± 8.59 mg; p = 0.001).

CONCLUSIONS

JAKi were effective in most refractory ASS patients as evidenced by improved skin rash, myositis, and ILD. However, larger prospective controlled studies are required to evaluate its efficacy.

[Autoantibody diagnostics in idiopathic inflammatory myopathy]

Idiopathic inflammatory myopathy (IIM) is a group of rare and heterogeneous systemic diseases that manifest not only in the muscles but also in the skin, joints, and lungs. Initial symptoms can be isolated and variable and thus the diagnosis poses challenges to various specialist groups. As autoantibodies are sometimes the only specific findings that lead to the diagnosis and appropriate treatment, basic knowledge of them is essential. This article explains the available test systems, names the clinical indications necessary for the initiation of autoantibody diagnostics, provides information on the etymology, antigens, synonyms, and first descriptors, describes indirect immunofluorescence on HEp‑2 cells induced by myositis antibodies, and provides clinical-serological associations. The comparison of the autoantibody findings with the clinical symptoms and laboratory findings enables the identification of false positive or false negative laboratory findings in the sense of a plausibility check.

Progressive pulmonary fibrosis in myositis-specific antibody-positive interstitial pneumonia: a retrospective cohort study

Objectives

Idiopathic inflammatory myopathy (IIM) frequently coexists with interstitial pneumonia (IP) and is commonly the initial or sole manifestation accompanied by positive myositis-specific autoantibodies (MSAs), even in the absence of meeting diagnostic criteria. This study aims to evaluate the proportion of progressive pulmonary fibrosis (PPF) and identify potential predictors influencing the progression of pulmonary fibrosis in patients with MSA-IP.

Methods

This descriptive study employed a retrospective cohort design, enrolling patients diagnosed with interstitial pneumonia and positive MSAs at Beijing Chao-Yang Hospital in a sequential manner. Clinical data were systematically collected from the patients' medical records during regular follow-up visits conducted every 3 to 6 months. Cox regression analysis was utilized to identify independent predictors of PPF in patients with positive MSAs and interstitial pneumonia.

Results

A total of 307 patients were included in the study, with 30.6% of them developing PPF during a median follow-up period of 22 months. Kaplan-Meier survival curves demonstrated a significantly lower survival in the PPF patients compared to the non-PPF patients (median 11.6 months vs. 31 months, p = 0.000). An acute/subacute onset of interstitial pneumonia (HR 3.231, 95%CI 1.936-5.392, p = 0.000), lower diffusing capacity of the lungs for carbon monoxide (DLCO) % predicted (HR 6.435, 95%CI 4.072-10.017, p = 0.001), and the presence of diffuse alveolar damage (DAD) on high-resolution computed tomography (HRCT) (HR 8.679, 95%CI 1.974-38.157, p = 0.004) emerged as independent predictors of PPF. Notably, the implementation of triple therapy comprising glucocorticoids, immunosuppressants, and antifibrotic drugs was associated with a reduced risk of developing PPF (HR 0.322, 95%CI 0.115-0.899, p = 0.031).

Conclusion

Approximately 30.6% of patients with MSA-IP may develop PPF within the follow-up period. Patients presenting with an acute/subacute onset of interstitial pneumonia, lower predicted DLCO SB% and evidence of DAD on HRCT are more susceptible to developing PPF. Conversely, the administration of triple therapy appears to serve as a protective factor against the development of PPF in patients with MSA-IP.

Epidemiology of the idiopathic inflammatory myopathies

The idiopathic inflammatory myopathies (IIMs) are a heterogeneous group of systemic autoimmune diseases that affect the skeletal muscles and can also involve the skin, joints, lungs and heart. The epidemiology of IIM is obscured by changing classification criteria and the inherent shortcomings of case identification using healthcare record diagnostic coding. The incidence of IIM is estimated to range from 0.2 to 2 per 100,000 person-years, with prevalence from 2 to 25 per 100,000 people. Although the effects of age and gender on incidence are known, there is only sparse understanding of ethnic differences, particularly in indigenous populations. The incidence of IIM has reportedly increased in the twenty-first century, but whether this is a genuine increase is not yet known. Understanding of the genetic risk factors for different IIM subtypes has advanced considerably. Infections, medications, malignancy and geography are also commonly identified risk factors. Potentially, the COVID-19 pandemic has altered IIM incidence, although evidence of this occurrence is limited to case reports and small case series. Consideration of the current understanding of the epidemiology of IIM can highlight important areas of interest for future research into these rare diseases.

Clinical characteristics and prognostic analysis of idiopathic inflammatory myopathy with positive anti-aminoacyl-tRNA synthetase antibodies: A single center experience

OBJECTIVES

To identify the differences of clinical characteristics, laboratory findings, and the long-term outcomes in patients with anti-synthetase syndrome (ASS) of different anti-aminoacyl-transfer RNA synthetase antibodies.

METHODS

We retrospectively enrolled 119 patients with ASS, and the clinical characteristics and laboratory findings were collected. Additionally, multivariate COX regression analysis was performed to estimate the risk factors of prognosis in patients with ASS.

RESULTS

The frequency of interstitial lung disease (ILD) reached 93.3% in our cohort, of 28 (23.5%) was classified as rapidly progressive (RP)-ILD. The highest incidence of RP-ILD was 36.4% in the PL12 group of ASS patients. The ILD group was characterized by an older age, a lower prevalence of V sign, and a higher prevalence of pulmonary symptoms when contrasted with the non-ILD group. There were statistical differences of clinical significance in arthritis, myositis, mechanic's hands, triad, shawl sign, V sign, and Raynaud's phenomenon among the four subgroups (all p < .05). Additionally, the prevalence rates of arthritis, myositis, mechanic's hands, triad, and V sign in the anti-Jo1 antibody-positive group were significantly higher than anti-Jo1 antibody-negative patients with ASS (all p < .05). Multivariate Cox regression analysis showed mechanic's hands (odds ratio [OR] = 6.47, p < .001), anti-nuclear antibodies (ANA) (OR = 2.13, p = .026), ILD (OR = 10.50, p < .001), and V sign (OR = 0.30, p = .007) were independent factors affecting the prognosis of patients with ASS. The incidences of RP-ILD, arthritis, myositis, triad, mechanic's hands, and shawl sign were more frequent in the anti-Ro52 antibody-positive group than the anti-Ro52 antibody-negative patients with ASS (all p < .05).

CONCLUSIONS

Patients with ASS accompanied with ILD are highly prevalent. Mechanic's hands, ANA, and ILD may be a potential biomarker for predicting a poor prognosis in patients with ASS. Additionally, the detection of the anti-Ro52 antibody provides valuable insights for managing and predicting disease progression and long-term outcomes.

Clinical Characteristics of Anti-Synthetase Syndrome and Variables Associated with Interstitial Lung Disease and Mortality: A Retrospective Cohort Study

Anti-synthetase syndrome (ASS) is a rare autoimmune disease. Since the knowledge of ASS remains limited, we conducted the retrospective study aiming to describe clinical characteristics and identify variables associated with interstitial lung disease (ILD) and mortality among patients with ASS. Patients diagnosed with ASS from January 2013 to October 2022 were included. Patient demographics, clinical manifestations, myositis auto-antibody profiles, HRCT findings, and laboratory tests were collected. Variables associated with mortality risk and ILD were evaluated using the Cox proportional hazards model and the logistic regression model, respectively. A total of 82 patients with ASS were included. Clinical manifestations included arthritis (57%), Raynaud's phenomenon (32%), mechanic's hands (29%), fever (26%), and myositis (17%). The myositis auto-antibody profiles included anti-PL-7 (29%), anti-Jo-1 (27%), anti-EJ (17%), anti-PL-12 (16%), and anti-OJ (11%). ILD was observed in 64 patients (78%). Among patients with ILD, 21 initially presented with ILD before developing other ASS clinical manifestations, 29 simultaneously presented with ILD and other symptoms, and 14 had isolated ILD throughout follow-up. Overall, 6 patients presented with rapid-progressive ILD. With a median follow-up time of 2.5 years, mortality was observed in 10 patients (12.2%). Factors associated with mortality included increased lymphocyte counts (adjusted HR, 0.74; 95% CI, 0.61-0.91; p < 0.01), isolated ILD (adjusted HR, 9.59; 95% CI, 1.52-60.61; p = 0.02) and the presence of anti-Ro52 antibodies (adjusted HR, 0.14; 95% CI, 0.02-0.93; p = 0.04). Factors associated with ILD included age (adjusted OR, 1.10; 95% CI, 1.03-1.18; p = 0.01), presence of anti-Ro52 antibodies (adjusted OR, 17.92; 95% CI, 2.13-138.68; p = 0.01), and presence of arthritis (adjusted OR, 0.09; 95% CI, 0.01-0.75; p = 0.03). Our study demonstrated a favorable overall mortality rate among ASS patients.