Anti-synthetase syndrome masquerading as recurrent pneumonia.

Anti-synthetase syndrome (ASS) is a rare inflammatory myopathy with a wide variety of clinical presentations. ASS-related interstitial lung disease (ASS-ILD) presents with rapid onset and progression, which could often be confused with other more common acute processes such as pneumonia, especially when ILD can be the sole manifestation. A woman in her 50s presented with recurrent dyspnoea for 2 months requiring multiple hospital admissions, and each time, she was diagnosed with multifocal pneumonia and treated with antibiotics. On admission, the evaluation revealed a markedly elevated creatine kinase level at 3258 U/L and a CT scan of the chest revealed worsening scattered ground-glass opacities. Given the concern for ILD as the cause of antibiotic failure, she underwent bronchoscopy with bronchoalveolar lavage which revealed non-specific interstitial pneumonia. A subsequent myositis panel revealed a positive anti-Jo-1 antibody, and she was diagnosed with ASS-ILD. She completed a course of intravenous immunoglobulin and methylprednisolone and experienced significant clinical improvement with the resolution of hypoxaemia and improved polyarthralgia.ASS could often be misdiagnosed as other more common acute lung processes, as a clinically subtle course can escape detection given its rarity, as well as its non-specific and highly variable presentations. This case highlights the importance of early suspicion and consideration of performing specific autoantibody testing when evaluating patients with a suspicion of undifferentiated autoimmune condition.

A machine learning analysis to evaluate the outcome measures in inflammatory myopathies.

OBJECTIVE: To assess the long-term outcome in patients with Idiopathic Inflammatory Myopathies (IIM), focusing on damage and activity disease indexes using artificial intelligence (AI). BACKGROUND: IIM are a group of rare diseases characterized by involvement of different organs in addition to the musculoskeletal. Machine Learning analyses large amounts of information, using different algorithms, decision-making processes and self-learning neural networks. METHODS: We evaluate the long-term outcome of 103 patients with IIM, diagnosed on 2017 EULAR/ACR criteria. We considered different parameters, including clinical manifestations and organ involvement, number and type of treatments, serum creatine kinase levels, muscle strength (MMT8 score), disease activity (MITAX score), disability (HAQ-DI score), disease damage (MDI score), and physician and patient global assessment (PGA). The data collected were analysed, applying, with R, supervised ML algorithms such as lasso, ridge, elastic net, classification, and regression trees (CART), random forest and support vector machines (SVM) to find the factors that best predict disease outcome. RESULTS AND CONCLUSION: Using artificial intelligence algorithms we identified the parameters that best correlate with the disease outcome in IIM. The best result was on MMT8 at follow-up, predicted by a CART regression tree algorithm. MITAX was predicted based on clinical features such as the presence of RP-ILD and skin involvement. A good predictive capacity was also demonstrated on damage scores: MDI and HAQ-DI. In the future Machine Learning will allow us to identify the strengths or weaknesses of the composite disease activity and damage scores, to validate new criteria or to implement classification criteria.

Inflammatory Myopathies.

PURPOSE OF REVIEW: This article outlines the salient clinical, serologic, electrophysiologic, imaging, and histopathologic findings and treatment options for the idiopathic inflammatory myopathies, including those related to immune checkpoint inhibitors and SARS-CoV-2. RECENT FINDINGS: The classification of idiopathic inflammatory myopathies has improved with the integration of myositis-specific antibodies and histopathologic findings. Characteristic features of immune checkpoint inhibitor-related myositis have been identified, allowing early recognition and treatment of the syndrome. The COVID-19 pandemic has had a profound impact on the care of patients with idiopathic inflammatory myopathies, and several mechanisms of virus-related muscle injury have been proposed. SUMMARY: A comprehensive evaluation including clinical examination, EMG, imaging, antibody testing, muscle biopsy, and cancer screening, when appropriate, can lead to an earlier accurate diagnosis and an individualized treatment approach for patients with idiopathic inflammatory myopathies.

Immune-mediated necrotizing myopathy (NAM) related to SARS-Cov-2 infection: a case report.

BACKGROUND: There is a growing body of evidence that severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) or COVID-19 infection is associated with the development of autoimmune diseases. A recent systematic review reported that the new-onset autoimmune disorders during or after COVID-19 infection included inflammatory myopathies such as immune-mediated necrotizing myopathies. CASE PRESENTATION: We described a 60-year-old man diagnosed with COVID-19 infection and later presented with a two-week history of myalgia, progressive limb weakness, and dysphagia. He had a Creatinine Kinase (CK) level of more than 10,000 U/L, was strongly positive for anti-signal recognition particle (SRP) and anti-Ro52 antibody, and a muscle biopsy revealed a paucity-inflammation necrotizing myopathy with randomly distributed necrotic fibers, which was consistent with necrotizing autoimmune myositis (NAM). He responded well clinically and biochemically to intravenous immunoglobulin, steroids and immunosuppressant and he was able to resume to his baseline. CONCLUSION: SARS-CoV-2 may be associated with late-onset necrotizing myositis, mimicking autoimmune inflammatory myositis.

Increased rates of idiopathic inflammatory myopathies during the COVID-19 pandemic: a single-centre experience.

OBJECTIVES: Higher-level evidence is required to discern whether the incidence of idiopathic inflammatory myopathies (IIM) has increased during the COVID-19 pandemic and whether the disease pattern and course have changed. We aimed to analyse patients who were diagnosed with IIM at our tertiary care centre during the pandemic and compare them with IIM patients diagnosed before COVID-19. METHODS: We retrospectively analysed the medical records of adult patients (>18 years) who were diagnosed with IIM during COVID-19 versus a control group of patients diagnosed before the outbreak. Included were patients whose diagnosis was made at the Department of Medicine and Rheumatology Unit of Hadassah Medical Center, Jerusalem, Israel. We also conducted a comprehensive review of the literature regarding SARS-CoV-2 infection and vaccine-induced IIM. RESULTS: Our study yielded 18 and 16 diagnosed IIM patients over periods of 27 and 56 months in the COVID-19 and pre-pandemic cohorts, respectively. These constitute incidence rates of 0.66 and 0.28 patients/month, respectively, marking an increased rate in the COVID-19 group. Unique features were noted in IIM patients who were diagnosed during the pandemic. This includes male predominance (M:F ratio of 12:6), higher hospitalisation rate (0.77 vs. 0.43 admitted/total patients) and increased number of patients with CPK >10,000 U/L (3 vs. 1 patient). Despite the more severe presentation and course in the pandemic group, survival was comparable between the groups. CONCLUSIONS: The incidence of IIM increased during the COVID-19 pandemic. These patients display unique features and a more severe presentation. Fortunately, the prognosis remains unchanged.

Rituximab-induced hypogammaglobulinaemia in patients affected by idiopathic inflammatory myopathies: a multicentre study.

OBJECTIVES: Rituximab (RTX) is an anti-CD20 chimeric monoclonal antibody recommended as off-label treatment in patients with idiopathic inflammatory myopathies (IIM). The present study aimed to evaluate changes in immunoglobulin (Ig) levels during RTX-treatment and their potential association with infections in a cohort of IIM patients. METHODS: Patients evaluated in the Myositis clinic belonging to the Rheumatology Units of Siena, Bari and Palermo University Hospitals, and treated for the first time with RTX were enrolled. Demographic, clinical, laboratory and treatment variables, including previous and concomitant immunosuppressive drugs and glucocorticoid (GC) dosage were analysed before (T0) and after 6 (T1) and 12 (T2) months of RTX treatment. RESULTS: Thirty patients (median age, IQR 56 (42-66); 22 female) were selected. During the observational period, low levels of IgG (<700 mg/dl) and IgM (<40 mg/dl) occurred in 10% and 17% of patients, respectively. However, no one showed severe (IgG<400 mg/dl) hypogammaglobulinaemia. IgA concentrations were lower at T1 than T0 (p=0.0218), while IgG concentrations were lower at T2 compared to those at baseline (p=0.0335). IgM concentrations were lower at T1 and T2 than T0 (p<0.0001), as well at T2 than T1 (p=0.0215). Three patients suffered major infections, two others had paucisymptomatic COVID-19, one suffered from mild zoster. GC dosages at T0 were inversely correlated with IgA T0 concentrations (p=0.004, r=- 0.514). No correlation was found between demographic, clinical and treatment variables and Ig serum levels. CONCLUSIONS: Hypogammaglobulinaemia following RTX is uncommon in IIM and is not related to any clinical variables, including GC dosage and previous treatments. IgG and IgM monitoring after RTX treatment does not seem useful in stratifying patients who require closer safety monitoring and prevention of infection, due to the lack of association between hypogammaglobulinaemia and the onset of severe infections.

Pain in individuals with idiopathic inflammatory myopathies, other systemic autoimmune rheumatic diseases, and without rheumatic diseases: A report from the COVAD study.

OBJECTIVES: To compare pain intensity among individuals with idiopathic inflammatory myopathies (IIMs), other systemic autoimmune rheumatic diseases (AIRDs), and without rheumatic disease (wAIDs). METHODS: Data were collected from the COVID-19 Vaccination in Autoimmune Diseases (COVAD) study, an international cross-sectional online survey, from December 2020 to August 2021. Pain experienced in the preceding week was assessed using numeral rating scale (NRS). We performed a negative binomial regression analysis to assess pain in IIMs subtypes and whether demographics, disease activity, general health status, and physical function had an impact on pain scores. RESULTS: Of 6988 participants included, 15.1% had IIMs, 27.9% had other AIRDs, and 57.0% were wAIDs. The median pain NRS in patients with IIMs, other AIRDs, and wAIDs were 2.0 (interquartile range [IQR] = 1.0-5.0), 3.0 (IQR = 1.0-6.0), and 1.0 (IQR = 0-2.0), respectively (P < 0.001). Regression analysis adjusted for gender, age, and ethnicity revealed that overlap myositis and antisynthetase syndrome had the highest pain (NRS = 4.0, 95% CI = 3.5-4.5, and NRS = 3.6, 95% CI = 3.1-4.1, respectively). An additional association between pain and poor functional status was observed in all groups. Female gender was associated with higher pain scores in almost all scenarios. Increasing age was associated with higher pain NRS scores in some scenarios of disease activity, and Asian and Hispanic ethnicities had reduced pain scores in some functional status scenarios. CONCLUSION: Patients with IIMs reported higher pain levels than wAIDs, but less than patients with other AIRDs. Pain is a disabling manifestation of IIMs and is associated with a poor functional status.

Positive myositis-specific autoantibodies during COVID-19: a case report.

Viral infection is known to be a trigger of autoimmune diseases. Numerous cases of coronavirus disease 2019 (COVID-19) with autoimmune manifestations have been reported and several authors have highlighted the relationship between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and autoimmune diseases. Autoimmune myopathies being one of these manifestations. A 27-year-old diabetic woman was admitted for management of acido-ketosis decompensation of her diabetes secondary to SARS-CoV-2 infection. During hospitalization, she developed muscle weakness and increased creatine kinase levels, which led us to assay the autoimmunity pattern which became positive for myositis-specific autoantibodies against single recognition particle (anti-SRP). The patient was treated with intense hydration with clinical and biological improvement and anti-SRP disappeared two months later. Positive myositis auto-antibodies are one of the autoimmune complications that could be seen during and after the SARS-CoV-2 infection.

A case of antisynthetase syndrome presenting solely with life-threatening interstitial lung disease.

A previously fit and well 38-year-old man presented during the COVID-19 pandemic with dyspnoea, cough and palpitations. C-reactive protein was elevated and chest X-ray demonstrated bilateral lower zone consolidation. SARS CoV-2 swab was negative. He was diagnosed with community-acquired pneumonia and treated with oral antibiotics. He developed severe type 1 respiratory failure and was admitted to the high-dependency unit for non-invasive ventilation. CTPA was negative for pulmonary embolism, instead demonstrating bilateral organising pneumonia. Empirical treatment for swab-negative COVID-19 pneumonitis was started; however, further deterioration ensued and prompted intubation and ventilation. Microbiological testing did not yield any positive results, thereby raising suspicion for the presence of an autoimmune disease. Pulsed intravenous methylprednisolone was administered with good effect. ENA screen was positive for anti-Jo1 and myositis-specific autoantibodies were positive for Ro-52, Ku and PL-12. The patient was extubated and did not exhibit any muscle weakness on clinical examination. Creatine kinase was only mildly elevated. He was diagnosed with amyopathic antisynthetase syndrome - frequently considered as a form of idiopathic inflammatory myopathy (IIM) - and treated with further intravenous methylprednisolone and cyclophosphamide. Oxygen therapy was gradually weaned and the patient discharged on mycophenolate mofetil and a weaning course of oral steroids.

Necrotizing autoimmune myositis following coronavirus disease 2019 infection: a case report.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 may be associated with late-onset necrotizing myositis, mimicking autoimmune inflammatory myositis; however, the exact underlying pathogenesis of severe acute respiratory syndrome coronavirus 2-induced myositis is still unclear. CASE PRESENTATION: Herein, we report a rare case of necrotizing autoimmune myositis in a 67-year-old middle eastern male following coronavirus disease 2019 infection, who presented with muscle weakness. The patient had positive anti-NXP2. The diagnosis of necrotizing autoimmune myositis was made according to muscle weakness, increased liver enzymes, electromyography and nerve conduction velocity results, and muscle biopsy. The patient underwent a full malignancy evaluation, which was unremarkable, and was discharged in relatively well condition with a daily dose of 1 mg/kg prednisolone and azathioprine 150 mg (2 mg/kg). CONCLUSION: Our report highlights the already known possible protracted sequence of coronavirus disease 2019 infection and the potential for delayed-onset necrotizing myositis.

What Is in the Myopathy Literature?

ABSTRACT: We cover intensive care unit-acquired neuromuscular disorders associated with coronavirus disease 2019. Outcomes may be worse than expected in these patients, and there is some evidence that coronavirus disease 2019 causes myopathy directly. Corticosteroid regimens in Duchenne muscular dystrophy are addressed including outcomes in pulmonary and cardiac function. A recent article notes a continued diagnostic delay in Duchenne muscular dystrophy. An interesting report of a Canary Islands cohort of patients with oculopharyngeal muscular dystrophy is discussed. Features and clinical pearls related to a series of patients with limb-girdle muscle dystrophy R12 (anoctaminopathy) and a misdiagnosis of idiopathic inflammatory myopathy are provided. The last section on autoimmune myopathy includes articles on clinical and pathologic features associated with myositis-specific antibodies and dermatomyositis, the epidemiology of immune-mediated necrotizing myopathies (IMNMs) in Olmsted County, Minnesota, and features of a German cohort of hydroxy-3-methylglutaryl coenzyme A reductase-associated IMNM. A recent article proposes the benefit of early intravenous immunoglobulin use for adults with IMNM. We also highlight a report of 2 unusual cases of antisignal recognition particle myopathy presenting with asymmetric distal weakness.

Antisynthetase syndrome sine myositis presenting as severe acute respiratory failure.

A female in her late 40s presented to the emergency department during the COVID-19 pandemic with shortness of breath, fever and productive cough following a recent diagnosis of bilateral non-massive pulmonary emboli. She had elevated inflammatory markers and her chest X-ray revealed bilateral infiltrates. Her SARS-CoV-2 PCR was negative, and she was treated for community-acquired pneumonia. However, despite treatment she rapidly deteriorated and developed severe respiratory failure, requiring mechanical ventilation.On further investigation, she tested positive for anti-Jo-1 antibodies and a diagnosis of antisynthetase syndrome sine myositis was made. This led to successful treatment with high dose corticosteroids and intravenous immunoglobulin.This case highlights an uncommon presentation of a rare condition, as well as the benefits of working in a multidisciplinary team on the intensive care unit.

Complement in autoimmune inflammatory myopathies, the role of myositis-associated antibodies, COVID-19 associations, and muscle amyloid deposits.

INTRODUCTION: The inflammatory myopathies (IM) have now evolved into distinct subsets requiring clarification about their immunopathogenesis to guide applications of targeted therapies. AREAS COVERED: Immunohistopathologic criteria of IM with a focus on complement, anti-complement therapeutics, and other biologic immunotherapies. The COVID19-triggered muscle autoimmunity along with the correct interpretation of muscle amyloid deposits is discussed. EXPERT OPINION: The IM, unjustifiably referred as idiopathic, comprise Dermatomyositis (DM), Necrotizing Autoimmune Myositis (NAM), Anti-synthetase syndrome-overlap myositis (Anti-SS-OM), and Inclusion-Body-Myositis (IBM). In DM, complement activation with MAC-mediated endomysial microvascular destruction and perifascicular atrophy is the fundamental process, while innate immunity activation factors, INF1 and MxA, sense and secondarily enhance inflammation. Complement participates in muscle fiber necrosis from any cause and may facilitate muscle-fiber necrosis in NAM but seems unlikely that myositis-associated antibodies participate in complement-fixing. Accordingly, anti-complement therapeutics should be prioritized for DM. SARS-CoV-2 can potentially trigger muscle autoimmunity, but systematic studies are needed as the reported autopsy findings are not clinically relevant. In IBM, tiny amyloid deposits within muscle fibers are enhanced by inflammatory mediators contributing to myodegeneration; in contrast, spotty amyloid deposits in the endomysial connective tissue do not represent 'amyloid myopathy' but only have diagnostic value for amyloidosis due to any cause.

Clinicopathological Characteristics of Inflammatory Myositis Induced by COVID-19 Vaccine (Pfizer-BioNTech BNT162b2): A Case Report.

As more individuals were coronavirus disease 2019 (COVID-19) vaccinated, unexpected side effects appeared. Herein, we present the case of a 30-year-old man with myopathy in both extremities after the second dose of the Pfizer-BioNTech (BNT162b2) COVID-19 vaccine. Symptoms, swelling and pain, started from the proximal upper and lower extremities and extended to the distal parts. Although he underwent massive hydration, the muscle enzyme level continuously increased. He complained of dysphagia and dysarthria. Microscopically, muscle biopsy showed multifocal or scattered macrophage infiltration and degenerated myofibers. In contrast to general myopathy including inflammatory myositis and rhabdomyolysis, vaccine-induced inflammatory myositis shows a prolonged increase in muscle enzyme levels and multifocal macrophage infiltration with necrosis of the muscle fibers. Symptoms improved with glucocorticoid and immunosuppressive treatment. If vaccinated individuals experience severe and continuous muscle pain and swelling, clinicians should consider vaccine-induced inflammatory myositis, measure the muscle enzyme levels, and perform muscle biopsy for a definite diagnosis.

Differential diagnosis of necrotizing myopathy.

PURPOSE OF REVIEW: Necrotizing myopathy is a broad term. It includes patients with the recently described immune-mediated necrotizing myopathies (IMNM) who have specific antibodies, such as anti-hydroxy-3-methylglutaryl-CoA reductase or anti-signal recognition particle, seronegative phenotypes that can be associated with cancer, and other types of myositis and connective tissue diseases involving necrotic muscle fibers as a characteristic pathologic feature. Necrotizing myopathies that are not immune-mediated, such as those caused by drugs, dystrophies, infections, or even hypothyroidism are also included. The purpose of this review is to address the differential diagnosis of these disorders. RECENT FINDINGS: New IMNM have been described over the last few years, some of them related with checkpoint inhibitors, drugs that are being increasingly used in cancer treatment. Necrotizing myopathy has also been reported in association with specific phenotypes and autoantibodies (e.g. anti-Mi2 dermatomyositis, antisynthetase syndrome, and myositis associated with antimitochondrial antibodies). Rarer cases associated with graft-versus-host disease and severe acute respiratory syndrome coronavirus 2 infection are also emerging. SUMMARY: Differentiation between patients with IMNM and those without the superimposed autoimmune phenomena helps clinicians determine the best individualized approach to use and the appropriate immunosuppressive therapy, whenever needed.

From influenza to SARS-CoV-2: etiological evaluation of acute benign childhood myositis.

AIM: To present the etiological evaluation results of our acute benign childhood myositis cases. MATERIALS AND METHODS: Children, who were referred to pediatric neurology outpatient clinic in Maternity and Children's Hospital, with difficulty in walking and high creatinine kinase levels were evaluated. Viral and bacterial serological evaluation of children were performed by real-time polymerase chain reaction method. RESULTS: Twenty-five children (21 M,4 F) included in the study. The most common complaints were walking difficulty and tenderness, pain on the gastrocnemius muscles. Their creatine kinase levels were between 216 and 8770 IU. Twenty-two children were hospitalized. Analgesic, intravenous fluid, antibiotic and/or antiviral drugs were given. The most common etiologies were influenza A and B. One children was diagnosed as suspected COVID-19 by the symptoms and the findings in thorax computerized tomography but the SARS-CoV-2 PCR and antibody tests were negative. CONCLUSION: School-aged children admitted to hospital with walking difficulty generally after an upper respiratory tract infection with a moderate creatine kinase elevation should remind at first acute benign myositis. Resolution of the complaints in a short time and normalisation of the biochemical markers will prevent unnecessary tests. Endemic and pandemic infections may cause this entity as well.

Severe acute inflammatory myositis and rhabdomyolysis in paediatric SARS-CoV-2-associated MIS-C (multisystem inflammatory syndrome in children).

We present the case of a 12-year-old African girl infected with SARS-CoV-2 who was admitted to a tertiary academic hospital in Johannesburg with severe acute inflammatory myositis complicated by rhabdomyolysis and acute kidney injury requiring renal replacement therapy and intensive care. She also fulfilled the diagnostic criteria for multisystem inflammatory syndrome in children.