Long-lasting improvement of refractory antisynthetase syndrome with tocilizumab: a report of two cases

Hidden in Plain Sight: Antisynthetase Syndrome Masquerading As Acute Coronary Syndrome and Heart Failure

A middle-aged man presented with fever, generalized myalgia, dyspnea, and worsening chest discomfort. Initial investigations showed elevated troponin and creatinine kinase levels and nonspecific ECG changes. Pulmonary embolism was ruled out, and high-resolution CT (HRCT) revealed ground-glass opacities and nonspecific interstitial pneumonia (NSIP)/organizing pneumonia (OP) overlap pattern. Given the elevated creatinine kinase level, antisynthetase syndrome with rapidly progressive interstitial lung disease (RP-ILD) was suspected. Treatment with pulse-dose methylprednisolone and tacrolimus led to significant clinical improvement, with HRCT showing resolution of the NSIP/OP findings on follow-up. This case highlights the importance of early diagnosis and multidisciplinary management in antisynthetase syndrome.

Interleukin 6 inhibition in refractory antisynthetase syndrome: case-based literature review

INTRODUCTION

Antisynthetase syndrome (ASyS) is a rare idiopathic inflammatory myopathy (IIM), characterised by the presence of anti-aminoacyl tRNA synthetase antibodies. Significant clinical heterogeneity often results in delayed or missed diagnoses. While corticosteroids are the primary treatment for ASyS, immunosuppressants are frequently added as steroid-sparing agents. In cases where conventional therapies have limited efficacy, the use of biological disease-modifying anti-rheumatic drugs (bDMARDs) is increasingly being explored. Given the suggested role of interleukin 6 (IL-6) in the onset and progression of ASyS, its inhibition could be a potential therapeutic option. Nevertheless, the clinical effects of IL-6 blockade remain to be awaited, given the unpredictability of its anti- and pro-inflammatory effects. Off-label use of IL-6 antagonists has shown favourable results in selected cases with ASyS.

MATERIAL AND METHODS

In this manuscript we present two patients with insufficient response to conventional treatment who received tocilizumab and sarilumab, two bDMARDs targeting IL-6.

RESULTS

Both patients had significant improvement in follow-up laboratory and pulmonary parameters as well as clinical symptoms with an additional corticoid-sparing effect. The treatment was well tolerated.

CONCLUSION

Future randomised clinical trials in a selected ASyS patient population could elucidate the efficacy of IL-6 inhibition in this specific IIM subgroup.

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.

Novel Therapeutic Approaches in Connective Tissue Disease-Associated Interstitial Lung Disease

Connective tissue diseases (CTD) comprise a group of autoimmune diseases that can affect multiple organs in the body including the lungs. The most common form of pulmonary involvement is interstitial lung disease (ILD). CTD-associated ILD (CTD-ILD) can take one of several courses including nonprogressive, chronically progressive, or rapidly progressive. Chronically and rapidly progressive patterns are associated with increased mortality. Limited randomized controlled trial data are available for treatment of CTD-ILD, with most data coming from systemic sclerosis-related ILD. The current first-line treatment for all CTD-ILD is immunosuppression with consideration of antifibrotics, stem cell transplant, and lung transplant in progressive disease. In this article, we review data for ILD treatment options in systemic sclerosis, rheumatoid arthritis, myositis, and primary Sjögren's syndrome-related ILDs.

A Review of Antisynthetase Syndrome-Associated Interstitial Lung Disease

Our objective in this review article is to present a clinical case of a patient with antisynthetase syndrome (ASyS) and provide an overview of the pathogenesis, classification criteria, antibody profiles, clinical features, and current knowledge of treatment options, focusing on interstitial lung disease (ILD). ASyS is an uncommon autoimmune disease with a heterogenous clinical presentation characterized by the presence of autoantibodies against an aminoacyl-tRNA synthetase and manifested by myositis, fever, inflammatory arthritis, Raynaud's phenomenon, mechanics hands, and ILD. ASyS-associated ILD (ASyS-ILD) is the most serious complication of ASyS, which may evolve to rapidly progressive ILD; therefore, it often requires thorough clinical and radiologic evaluation including recognition of a specific clinical phenotype associated with the antisynthetase antibodies (ASAbs) to guide therapeutic interventions.