Severe acute myositis and myocarditis on initiation of 6-weekly pembrolizumab post-COVID-19 mRNA vaccination.

We describe three cases of critical acute myositis with myocarditis occurring within 22 days of each other at a single institution, all within 1 month of receiving the initial cycle of the anti-PD-1 drug pembrolizumab. Analysis of T cell receptor repertoires from peripheral blood and tissues revealed a high degree of clonal expansion and public clones between cases, with several T cell clones expanded within the skeletal muscle putatively recognizing viral epitopes. All patients had recently received a COVID-19 mRNA booster vaccine prior to treatment and were positive for SARS-CoV2 Spike antibody. In conclusion, we report a series of unusually severe myositis and myocarditis following PD-1 blockade and the COVID-19 mRNA vaccination.

Anti-synthase syndrome associated with SARS-Cov-2 infection.

BACKGROUND: Anti-synthetase syndrome (AS) is a rare autoimmune idiopathic inflammatory myopathy (IIM) with diverse manifestations, including arthritis, interstitial lung disease (ILD), Raynaud's phenomenon, unexplained persistent fever, and mechanic's hands. CASE PRESENTATION: We present the case of a 72-year-old woman, previously healthy, who was admitted to our hospital for treatment of cough and rapid breathing. The patient had elevated white blood cells and C-reactive protein, and tested negative for severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2). She was initially diagnosed with community-acquired pneumonia and received tamoxifen for anti-infection treatment, but her dystonia worsened. She eventually required non-invasive ventilator support, tested positive for SARS-Cov-2 again, and started antiviral therapy, corticosteroids to reduce alveolar effusion, anticoagulation, and other treatments. However, her condition continued to deteriorate, with the lowest oxygenation index reaching only 80mmHg. Ultimately, she underwent tracheal intubation and mechanical ventilation. Chest CT revealed rapid progressive interstitial changes in her lungs, and her hands showed noticeable fraternization changes. At this point, we suspected that the novel coronavirus infection might be associated with autoimmune diseases. The patient's autoimmune antibody spectrum showed positive results for anti-recombinant RO-52 antibody and myositis-specific antibody anti-alanyl tRNA synthetase (anti-PL-12). The patient was treated with dexamethasone sodium phosphate for anti-inflammatory and anti-fibrotic effects. After successful extubation, the patient was discharged with only oral prednisone tablets at a dose of 30 mg. CONCLUSIONS: This case presents an early diagnosis and successful treatment of anti-synthetase syndrome combined with SARS-Cov-2 infection, emphasizing the importance of comprehensive physical examination. Additionally, it highlights the rapid progression of interstitial lung disease under SARS-Cov-2 infection, which is often difficult to distinguish on imaging. In cases where treatment for SARS-Cov-2 infection is ineffective, early screening for autoimmune diseases is recommended. As there is currently no standardized method for treating AS-ILD, the successful treatment of this case provides a reference for clinical research on anti-synthetase syndrome in the later stage.

Novel and potential future therapeutic options in systemic autoimmune diseases.

Autoimmune inflammation is caused by the loss of tolerance to specific self-antigens and can result in organ-specific or systemic disorders. Systemic autoimmune diseases affect a significant portion of the population with an increasing rate of incidence, which means that is essential to have effective therapies to control these chronic disorders. Unfortunately, several patients with systemic autoimmune diseases do not respond at all or just partially respond to available conventional synthetic disease-modifying antirheumatic drugs and targeted therapies. However, during the past few years, some new medications have been approved and can be used in real-life clinical settings. Meanwhile, several new candidates appeared and can offer promising novel treatment options in the future. Here, we summarize the newly available medications and the most encouraging drug candidates in the treatment of systemic lupus erythematosus, rheumatoid arthritis, Sjögren's disease, systemic sclerosis, systemic vasculitis, and autoimmune myositis.

[Magnetic resonance imaging T2 mapping could reflect disease status in patients with dermatomyositis or polymyositis].

This study aimed to explore the value of magnetic resonance imaging (MRI) T2 mapping in the assessment of dermatomyositis (DM) and polymyositis (PM). Thirty-three confirmed cases (myosin group) and eight healthy volunteers (healthy control group) at the Department of Rheumatology and Immunology, the First Affiliated Hospital of Kunming Medical University, from October 2016 to December 2017, were collected and analyzed. Multiple parameters of the myosin group were quantified, including creatine kinase (CK), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), complement C3, and complement C4. Disease status was evaluated using a panel of tools: myositis disease activity assessment tool-muscle (MDAAT-muscle), myositis disease activity assessment tool-whole (MDAAT-all), health assessment questionnaire (HAQ), medical outcomes study health survey short form-36 item (SF-36), hand muscle strength test (MMT-8) score, and MRI T2 mapping of muscle (22 muscles in the pelvis and thighs) T2 values. The results showed that in the myositis group, the measurements for CK, ESR, CRP, complement C3, and complement C4 were 457.2 (165.6, 1 229.2) IU/L, 20 (10, 42) mm/1h, 3.25 (2.38, 10.07) mg/L, 0.90 (0.83, 1.06) g/L, and 0.18 (0.14, 0.23) g/L, respectively. The scores for MMT-8, MDAAT-muscle, MDAAT-all, HAQ, and SF-36 were 57.12±16.23, 5.34 (4.00, 6.00), 34.63±12.62, 1.55 (0.66, 2.59), and 44.66±7.98, respectively. T2 values were significantly higher in all 22 muscles of the pelvis and thighs of patients with DM or PM compared with the healthy controls [(54.99±11.60)ms vs. (36.62±1.66)ms, P<0.001], with the most severe lesions in the satrorius, iliopsoas, piriformis, gluteus minimus, and gluteus medius muscles. The total muscle T2 value in the myositis group was positively correlated with CK, MDAAT-muscle, MDAAT-all, and HAQ (r=0.461, 0.506, 0.347, and 0.510, respectively, all P<0.05). There was a negative correlation between complement C4, SF-36, and MMT-8 scores (r=-0.424, -0.549, and -0.686, respectively, all P<0.05). Collectively, the findings from this study suggest that MRI T2 mapping can objectively reflect the disease status of DM and PM.

Unprecedented complexity of six coexisting autoimmune diseases: A case report.

INTRODUCTION: Autoimmune disorders often exhibit interconnectedness, although encountering multiple autoimmune conditions in a single patient is uncommon. Multiple autoimmune syndrome is characterized by the presence of at least three distinct autoimmune diseases in an individual. This report outlines the case of a middle-aged woman diagnosed with autoimmune thyroiditis, Sjögren's syndrome, scleroderma, autoimmune hepatitis, primary biliary cirrhosis, and antisynthetase syndrome. Additionally, it includes a literature review encompassing multiple autoimmune syndromes involving five or more autoimmune diseases. OBSERVATION: A 57-year-old woman, with no previous medical history, presented with fever, extensive muscle weakness, progressive exertional dyspnea, inflammatory polyarthralgia, dysphagia, and dry mouth. Clinical examination revealed muscular deficit in the scapular and pelvic girdles, distal muscular deficit, synovitis in the wrists, and features indicative of "mechanic's hand". Laboratory examinations showed cytolysis, cholestasis, elevated muscle enzymes, hypergammaglobulinemia and elevated thyroid stimulating hormone. Immunoassays showed positive results for antinuclear antibodies, anti-histidyl-t-RNA synthetase, anti-Sjögren's-syndrome-related antigen A, anti-ribonucleic-acid-polymerase-III-RP155, anti-fibrillarin, anti-mitochondrial, anti-liver/kidney microsomal type 1, anti-glycoprotein 210, and anti-thyroid peroxidase antibodies. Further investigations led to the diagnosis of a multiple autoimmune syndrome involving autoimmune thyroiditis, Sjögren's syndrome, scleroderma, autoimmune hepatitis, primary biliary cirrhosis, and antisynthetase syndrome. The patient received treatment with intravenous immunoglobulins, corticosteroids, azathioprine, and ursodeoxycholic acid, which resulted in favorable clinical and biological outcomes. CONCLUSION: This patient presented with six concurrent distinct autoimmune disorders, categorizing this case as a type two multiple autoimmune syndrome. The identification of antisynthetase syndrome notably distinguishes this case.

Pathological findings with vacuoles in anti-mitochondrial antibody-positive inflammatory myopathy.

BACKGROUND: A few patients with inflammatory myopathy showed anti-mitochondrial antibody (AMA) positivity. This study aimed to report the clinical and pathological findings with vacuoles in 3 cases of such patients. METHODS: Three cases with myositis from the Myositis Clinical Database of Peking University First Hospital were identified with AMA positivity. Their clinical records were retrospectively reviewed and the data was extracted. All the 3 cases underwent muscle biopsy. RESULTS: Three middle-aged patients presented with chronic-onset weakness of proximal limbs, marked elevation of creatine kinase, and AMA-positivity. Two of the 3 cases meet the criteria of primary biliary cholangitis. All the 3 cases presented with cardiac involvement and proteinuria. Two cases developed type 2 respiratory failure. MRI of the thigh muscle showed multiple patches of edema bilaterally in both cases, mostly in the adductor magnus. Pathological findings include degeneration of muscle fibers, diffused MHC-I positivity, and complement deposits on cell membranes. Vacuoles without rims of different sizes were discovered under the membrane of the muscle fibers. A few RBFs were discovered in case 1, while a diffused proliferation of endomysium and perimysium was shown in case 2. CONCLUSIONS: AMA-positive inflammatory myopathy is a disease that could affect multiple systems. Apart from inflammatory changes, the pathological findings of muscle can also present vacuoles.

Effectiveness and safety of mycophenolate mofetil and rituximab combination therapy for immune idiopathic myopathies.

INTRODUCTION: Idiopathic inflammatory myopathies (IIM) represent a rare and heterogenous group diseases, and their treatment is not fully defined yet. According to previous small case series, the combination of mycophenolate mofetil (MMF) and rituximab (RTX) may be effective in controlling difficult-to-treat patients. Our aim was to further explore the efficacy and safety of this combined approach in patients with IIM. METHODS: Patients with IIM treated with the RTX/MMF combination in our Center were retrospectively identified. After the start of combination therapy, the efficacy was evaluated at 12 months (T12) according the 2016 ACR/EULAR response criteria for IIM. Cardiac imaging and pulmonary function tests were used to monitor disease activity in patients with myocarditis and interstitial lung disease, respectively. Adverse events were recorded over the follow-up period. RESULTS: Among the 20 patients (median age 61 years; 70% female) included in the study, anti-synthetase syndrome was the most prevalent IIM subgroup (60%). At treatment start, muscle, heart, and lung were the most commonly actively affected organs. After 12 months, a moderate or major response was observed in all patients, and creatine kinase was significantly decreased (p-value = 0.012). Cardiac imaging and enzymes monitoring showed a reduction of heart inflammation, while pulmonary function tests improved in patients with lung involvement. No severe side effects were observed. CONCLUSION: Our data show that combination of RTX and MMF is effective and safe in patients with severe and refractory IIM. Therefore, this combined treatment might represent a feasible approach for difficult-to-treat IIM cases.

Diagnosing and characterizing inflammatory myopathies at an Australian tertiary public hospital: Resource utilization and direct healthcare costs.

AIM: To determine the direct health service costs and resource utilization associated with diagnosing and characterizing idiopathic inflammatory myopathies (IIMs), and to assess for limitations and diagnostic delay in current practice. METHODS: A retrospective, single-center cohort analysis of all patients diagnosed with IIMs between January 2012 and December 2021 in a large tertiary public hospital was conducted. Demographics, resource utilization and costs associated with diagnosing IIM and characterizing disease manifestations were identified using the hospital's electronic medical record and Health Intelligence Unit, and the Medicare Benefits Schedule. RESULTS: Thirty-eight IIM patients were identified. IIM subtypes included dermatomyositis (34.2%), inclusion body myositis (18.4%), immune-mediated necrotizing myopathy (18.4%), polymyositis (15.8%), and anti-synthetase syndrome (13.2%). The median time from symptom onset to diagnosis was 212 days (IQR: 118-722), while the median time from hospital presentation to diagnosis was 30 days (8-120). Seventy-six percent of patients required emergent hospitalization during their diagnosis, with a median length of stay of 8 days (4-15). The average total cost of diagnosing IIM was $15 618 AUD (STD: 11331) per patient. Fifty percent of patients underwent both MRI and EMG to identify affected muscles, 10% underwent both pan-CT and PET-CT for malignancy detection, and 5% underwent both open surgical and percutaneous muscle biopsies. Autoimmune serology was unnecessarily repeated in 37% of patients. CONCLUSION: The diagnosis of IIMs requires substantial and costly resource use; however, our study has identified potential limitations in current practice and highlighted the need for streamlined diagnostic algorithms to improve patient outcomes and reduce healthcare-related economic burden.

[A unicenter real-world study of the correlation factors for complete clinical response in idiopathic inflammatory myopathies].

OBJECTIVE: To investigate the correlation factors of complete clinical response in idiopathic inflammatory myopathies (IIMs) patients receiving conventional treatment. METHODS: Patients diagnosed with IIMs hospitalized in Peking University People's Hospital from January 2000 to June 2023 were included. The correlation factors of complete clinical response to conventional treatment were identified by analyzing the clinical characteristics, laboratory features, peripheral blood lymphocytes, immunological indicators, and therapeutic drugs. RESULTS: Among the 635 patients included, 518 patients finished the follow-up, with an average time of 36.8 months. The total complete clinical response rate of IIMs was 50.0% (259/518). The complete clinical response rate of dermatomyositis (DM), anti-synthetase syndrome (ASS) and immune-mediated necrotizing myopathy (IMNM) were 53.5%, 48.9% and 39.0%, respectively. Fever (P=0.002) and rapid progressive interstitial lung disease (RP-ILD) (P=0.014) were observed much more frequently in non-complete clinical response group than in complete clinical response group. The aspartate transaminase (AST), lactate dehydrogenase (LDH), D-dimer, erythrocyte sedimentation rate (ESR), C-reaction protein (CRP) and serum ferritin were significantly higher in non-complete clinical response group as compared with complete clinical response group. As for the treatment, the percentage of glucocorticoid received and intravenous immunoglobin (IVIG) were significantly higher in non-complete clinical response group than in complete clinical response group. Risk factor analysis showed that IMNM subtype (P=0.007), interstitial lung disease (ILD) (P=0.001), eleva-ted AST (P=0.012), elevated serum ferritin (P=0.016) and decreased count of CD4+T cells in peripheral blood (P=0.004) might be the risk factors for IIMs non-complete clinical response. CONCLUSION: The total complete clinical response rate of IIMs is low, especially for IMNM subtype. More effective intervention should be administered to patients with ILD, elevated AST, elevated serum ferritin or decreased count of CD4+T cells at disease onset.

[Current and Future Status of Muscle Pathology: The Position of Muscle Pathology Diagnosis in the Future].

Many muscle disease names are mostly based on muscle pathology findings. Naturally, muscle pathology is important in the diagnosis of muscle diseases. Moreover, in recent years, extensive genetic analysis and autoantibody testing for myositis have been applied clinically, although muscle biopsies are less performed. However, muscle pathology should be proactively considered when a single gene presents multiple phenotypes, when variants of unknown pathological significance are detected, or in cases of autoimmune myositis that may be misdiagnosed as muscular dystrophy.

Immune-Mediated Necrotizing Myopathies: Current Landscape.

PURPOSE OF REVIEW: Immune-mediated necrotizing myopathy (IMNM), characterized by acute or subacute onset, severe weakness, and elevated creatine kinase levels, poses diagnostic and therapeutic challenges. This article provides a succinct overview of IMNM, including clinical features, diagnostic strategies, and treatment approaches. RECENT FINDINGS: Recent insights highlight the different clinical presentations and therapeutic options of IMNM stratified by autoantibody positivity and type. Additionally, recent findings call into question the reported link between statin use and IMNM. This review synthesizes current knowledge on IMNM, emphasizing its distinct clinical features and challenging management. The evolving understanding of IMNM underscores the need for a comprehensive diagnostic approach that utilizes a growing range of modalities. Early and aggressive immunomodulatory therapy remains pivotal. Ongoing research aims to refine diagnostic tools and therapeutic interventions for this challenging muscle disorder, underscoring the importance of advancing our understanding to enhance patient outcomes.

Dynamic change in red cell distribution width as a predictor for short-time mortality in dermatomyositis-associated rapid progressive interstitial lung disease.

AIM: We aimed to explore a new and readily available practical marker for rapidly progressive interstitial lung disease (RP-ILD) and poor short-term outcomes in patients with idiopathic inflammatory myopathies (IIM). METHODS: A total of 1822 consecutive patients with IIM between 2009 and 2021 were evaluated retrospectively. All proven cases of naïve ILD with complete medical records were included. Red cell distribution width (RDW) values at the initial stage, 3 months and last follow-up were collected. The clinical characteristics and outcomes of the patients were recorded. RESULTS: We identified 532 patients with IIM with an average follow-up of 4 years. ILD prevalence was higher in patients of elevated RDW (p<0.001). The patients with ILD and elevated RDW had lower levels of PaO2/FiO2, FVC% and DLco% and a higher prevalence of RP-ILD than those with normal RDW (p<0.001). Prognostic analysis revealed that RDW was an independent risk factor for prognosis in patients with IIM-ILD (HR=2.9, p=0.03). Patients with dermatomyositis (DM) with RP-ILD with a change in RDW within 3 months (∆RDW-3) greater than 0 were more likely to die within 3 months. Moreover, the prevalence of ∆RDW-3>0 was higher in patients with RP-ILD and positive for anti-melanoma differentiation-associated gene 5 antibody who died within 3 months (87.5%) compared with those alive at 3 months (24.6%) (p<0.001). CONCLUSION: These findings suggest that repeated RDW assays could assist physicians in identifying patients with DM-ILD who were at a high risk of RP-ILD and death.

Myositis in H1N1 Infection Compounds to Myasthenic Crisis.

ABSTRACT: Infection is an important trigger of myasthenic crisis (MC), and those infections manifest with pneumonia and muscle involvement may result in more frequent MC. We report two myasthenia gravis (MG) patients with H1N1 infection, and highlight the reasons for deterioration. Two patients with MG had H1N1 infection. The diagnosis of MG was confirmed by neostigmine, repetitive nerve stimulation, and anti-acetylcholine receptor antibody tests. H1N1 was confirmed by nucleic acid detection study, and myositis by creatinine kinase. The patient with pneumonia and myositis had MC needing mechanical ventilation for 10 days, and the other patient without myositis did not have MC. They were treated with oseltamivir 75 mg twice daily for 5 days, and the patients with MC received ceftriaxone intravenously. Both the patients were on prednisolone and azathioprine, and none received prior H1N1 vaccination. The lady with MC with myositis was discharged on day 27 in wheelchair bound state, and the other one patient without myositis or MC was discharged on 6th day with full recovery. These patients highlight the need for evaluation for myositis along with pneumonia in the MG patients with H1N1 infection. Vaccination in MG patients on immunosuppression may be useful.

Recurrent inferior oblique myositis and its outcomes.

This report presents a unique case of recurrent idiopathic inferior oblique myositis (IOM) with a focus on clinico-radiological characteristics and histological features. A woman in her early 40s presented with a third episode of IOM following a 12-year period of quiescence. The first two episodes were characterised by unilateral IOM with rapid resolution following oral prednisone treatment. MRI revealed anterior focal enlargement of the left inferior oblique muscle with ipsilateral lacrimal gland enlargement. An inferior oblique muscle and lacrimal gland biopsy demonstrated significant inflammatory infiltrate. An intraorbital injection of triamcinolone acetonide was administered with complete resolution of symptoms within 1 week.

272nd ENMC international workshop: 10 Years of progress - revision of the ENMC 2013 diagnostic criteria for inclusion body myositis and clinical trial readiness. 16-18 June 2023, Hoofddorp, The Netherlands.

Since the publication of the 2013 European Neuromuscular Center (ENMC) diagnostic criteria for Inclusion Body Myositis (IBM), several advances have been made regarding IBM epidemiology, pathogenesis, diagnostic tools, and clinical trial readiness. Novel diagnostic tools include muscle imaging techniques such as MRI and ultrasound, and serological testing for cytosolic 5'-nucleotidase-1A antibodies. The 272nd ENMC workshop aimed to develop new diagnostic criteria, discuss clinical outcome measures and clinical trial readiness. The workshop started with patient representatives highlighting several understudied symptoms and the urge for a timely diagnosis. This was followed by presentations from IBM experts highlighting the new developments in the field. This report is composed of two parts, the first part providing new diagnostic criteria on which consensus was achieved. The second part focuses on the use of outcome measures in clinical practice and clinical trials, highlighting current limitations and outlining the goals for future studies.