COVID-19 as a putative trigger of anti-MDA5-associated dermatomyositis with acute respiratory distress syndrome (ARDS) requiring lung transplantation, a case report

Slowly Progressive Melanoma Differentiation-Associated Gene 5 (MDA-5) Interstitial Lung Disease Following COVID-19 Infections: A Pulmonary Puzzle

Melanoma differentiation-associated gene 5 (MDA-5) autoimmunity has been increasingly recognized in association with interstitial lung disease (ILD), particularly in the context of viral infections. While MDA-5 ILD is typically rapidly progressive with high mortality, emerging evidence suggests that COVID-19 may induce a distinct, more indolent phenotype. We report two cases of MDA-5 ILD following COVID-19 infection with a slowly progressive course. In Case 1, an 87-year-old woman with a history of breast cancer, chronic obstructive pulmonary disease (COPD), and a prior COVID-19 infection developed progressive dyspnea. Imaging revealed new-onset ILD with subpleural reticulations and traction bronchiectasis. A myositis antibody panel was positive for MDA-5 autoantibodies. She was diagnosed with MDA-5 ILD and initiated on corticosteroids, later transitioned to mycophenolate. She has since remained clinically stable over the past two years. In Case 2, an 84-year-old man with a history of smoking and asbestos exposure developed severe dyspnea and hypoxia after a mild COVID-19 infection. CT imaging revealed diffuse ground-glass opacities and interlobular septal thickening. He was diagnosed with MDA-5 ILD and Group 1 and 3 pulmonary hypertension. He was treated with mycophenolate and pulmonary vasodilators, leading to symptom stabilization. These cases illustrate a possible post-COVID-19 endotype of MDA-5 ILD that follows a slower disease trajectory, distinct from the classical rapidly progressive phenotype. The association between viral infections and MDA-5 autoimmunity is supported by prior studies demonstrating viral-induced interferon signaling and MDA-5 gene activation. Given the indolent nature of disease progression in our patients, a tailored immunosuppressive approach was pursued, resulting in the stabilization of symptoms and pulmonary function.  These cases contribute to the growing recognition of post-COVID-19 MDA-5 ILD as a unique clinical entity. Further research is needed to elucidate the precise mechanisms underlying virus-induced autoimmunity and to guide treatment strategies for this emerging ILD subtype.

Successful lung transplantation in RPILD associated with anti-MDA5ab+: A case report

RATIONALE

Lung transplantation in rapidly progressive interstitial lung disease associated with antimelanoma differentiation-associated gene 5 antibody positive may be a rescue therapy in case of medical treatment failure and impossible weaning from the ventilatory support.

PATIENT CONCERNS

A 59-year-old man with cough, expectoration, and fever for more than half a month, which aggravated with dyspnea for 4 days.

DIAGNOSES

Rapidly progressive interstitial lung disease was confirmed through chest high-resolution computed tomography and antimelanoma differentiation-associated gene 5 antibody positive.

INTERVENTIONS

The patient was given extracorporeal membrane oxygenation and double lung transplantation.

OUTCOMES

The patient is currently undergoing rehabilitation in a general ward and follow-up.

LESSONS

Lung transplantation should be considered when impossible weaning from the ventilatory support.

Solid Organ Transplants Caused by COVID-19 Infection and the Outcome of Transplantation Post-COVID-19: A Systematic Review

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic has imposed several medical and economic challenges since its onset in 2019. This is due to its ability to target the respiratory system as well as other organs, resulting in significant impacts and necessitating organ transplants. Our goal is to compile information from the existing literature to investigate how COVID-19 affects outcomes following organ transplantation. A comprehensive literature search was conducted to target studies reporting post-COVID-19 complications. We included 45 studies reporting data related to solid organ transplants, where either the recipient, organ, or donor was affected by SARS-CoV-2. The majority of the included studies concluded that organ transplantation following COVID-19 infection could be performed safely and with similar outcomes to non-COVID-19 patients, regardless of whether the organ, donor, or recipient was affected by COVID-19. No deviation from standard immunosuppression regimens or surgical protocols was necessary either, further re-assuring the feasibility of these transplants as viable treatment options. This applies to organ transplants involving the lungs, kidneys, liver, or heart. However, there was a limited number of studies in some areas, which warrants the need for additional research in order to reach more concrete conclusions pertaining to COVID-19's effect on organ transplants.

MDA5 Is a Major Determinant of Developing Symptoms in Critically Ill COVID-19 Patients

Apart from the skin and mucosal immune barrier, the first line of defense of the human immune system includes MDA5 (ifih1 gene) which acts as a cellular sensor protein for certain viruses including SARS-CoV-2. Upon binding with viral RNA, MDA5 activates cell-intrinsic innate immunity, humoral responses, and MAVS (mitochondrial antiviral signaling). MAVS signaling induces type I and III interferon (IFN) expressions that further induce ISGs (interferon stimulatory genes) expressions to initiate human cell-mediated immune responses and attenuate viral replication. SARS-CoV-2 counteracts by producing NSP1, NSP2, NSP3, NSP5, NSP7, NSP12, ORF3A, ORF9, N, and M protein and directs anti-MDA5 antibody production presumably to antagonize IFN signaling. Furthermore, COVID-19 resembles several diseases that carry anti-MDA5 antibodies and the current COVID-19 vaccines induced anti-MDA5 phenotypes in healthy individuals. GWAS (genome-wide association studies) identified several polymorphisms (SNPs) in the ifih1-ifn pathway genes including rs1990760 in ifih1 that are strongly associated with COVID-19, and the associated risk allele is correlated with reduced IFN production. The genetic association of SNPs in ifih1 and ifih1-ifn pathway genes reinforces the molecular findings of the critical roles of MDA5 in sensing SARS-CoV-2 and subsequently the IFN responses to inhibit viral replication and host immune evasion. Thus, MDA5 or its pathway genes could be targeted for therapeutic development of COVID-19.

Rapid Progression of Acute Interstitial Pneumonia in a Patient with Low MDA-5 Antibody Titer

BACKGROUND Melanoma differentiation associated gene-5 antibody (MDA-5 Ab) is one of the diagnostic autoantibodies that appears in idiopathic inflammatory myopathies (IIMs). Unlike when other autoantibodies are positive, when this antibody is positive, there is less characteristic muscle involvement. However, this MDA-5 Ab-positive myopathy presents extremely rapid progression of interstitial lung disease, resulting in a high mortality rate. Previous studies reported that the prognosis of this lung disease will be determined by the titer and suggest that low titers of MDA-5 antibody can indicate a good prognosis in associated interstitial lung disease. CASE REPORT Our case describes a 55-year-old woman who presented with acute respiratory symptoms and dyspnea. After hospitalization, symptoms and chest imaging worsened rapidly, and the radiology image of lung disease featured interstitial changes not seen in typical infections. We treated the patient with a high-flow oxygen nasal cannula, empirical antibiotics, and a systemic steroid. While treatment for a disease of unknown cause was continued, low titer of MDA-5 antibody was identified. CONCLUSIONS This case suggests 2 points to consider about non-infectious interstitial changes with acute respiratory distress syndrome. First, when treating rapidly progressing interstitial pneumonia of an unknown cause, it is recommended to consider lung involvement of MDA-5 Ab dermatomyositis. Second, a low titer of MDA-5 Ab can be associated with better prognosis in this MDA-5 Ab dermatomyositis-related lung disease.

MDA5-autoimmunity and interstitial pneumonitis contemporaneous with the COVID-19 pandemic (MIP-C)

BACKGROUND

Anti-MDA5 (Melanoma differentiation-associated protein-5) positive dermatomyositis (MDA5+-DM) is characterised by rapidly progressive interstitial lung disease (ILD) and high mortality. MDA5 is an RNA sensor and a key pattern recognition receptor for the SARS-CoV-2 virus.

METHODS

This is a retrospective observational study of a surge in MDA5 autoimmunity, as determined using a 15 muscle-specific autoantibodies (MSAs) panel, between Janurary 2018 and December 2022 in Yorkshire, UK. MDA5-positivity was correlated with clinical features and outcome, and regional SARS-CoV-2 positivity and vaccination rates. Gene expression patterns in COVID-19 were compared with autoimmune lung disease and idiopathic pulmonary fibrosis (IPF) to gain clues into the genesis of the observed MDA5+-DM outbreak.

FINDINGS

Sixty new anti-MDA5+, but not other MSAs surged between 2020 and 2022, increasing from 0.4% in 2019 to 2.1% (2020), 4.8% (2021) and 1.7% (2022). Few (8/60) had a prior history of confirmed COVID-19, peak rates overlapped with regional SARS-COV-2 community positivity rates in 2021, and 58% (35/60) had received anti-SARS-CoV-2 vaccines. 25/60 cases developed ILD which rapidly progression with death in 8 cases. Among the 35/60 non-ILD cases, 14 had myositis, 17 Raynaud phenomena and 10 had dermatomyositis spectrum rashes. Transcriptomic studies showed strong IFIH1 (gene encoding for MDA5) induction in COVID-19 and autoimmune-ILD, but not IPF, and IFIH1 strongly correlated with an IL-15-centric type-1 interferon response and an activated CD8+ T cell signature that is an immunologic hallmark of progressive ILD in the setting of systemic autoimmune rheumatic diseases. The IFIH1 rs1990760TT variant blunted such response.

INTERPRETATION

A distinct pattern of MDA5-autoimmunity cases surged contemporaneously with circulation of the SARS-COV-2 virus during COVID-19. Bioinformatic insights suggest a shared immunopathology with known autoimmune lung disease mechanisms.

FUNDING

This work was supported in part by the National Institute for Health Research (NIHR) Leeds Biomedical Research Centre (BRC), and in part by the National Institutes of Health (NIH) grant R01-AI155696 and pilot awards from the UC Office of the President (UCOP)-RGPO (R00RG2628, R00RG2642 and R01RG3780) to P.G. S.S was supported in part by R01-AI141630 (to P.G) and in part through funds from the American Association of Immunologists (AAI) Intersect Fellowship Program for Computational Scientists and Immunologists.

Anti-MDA5 antibody-positive dermatomyositis: pathogenesis and clinical progress

Anti-melanoma differentiation-associated protein 5 (MDA5) antibody-positive dermatomyositis (MDA5-DM) is a subtype of dermatomyositis. Although the aetiology and pathology remain unclear, increasing evidence suggests that viral infection is a potential trigger of MDA5-DM. Multiple factors, including T cells, B cells, neutrophils and macrophages, are implicated in the pathophysiology of MDA5-DM. Distinctive skin rashes, rapidly progressive interstitial lung disease, peripheral lymphopenia and elevated serum ferritin levels are the most prominent clinical and laboratory features of MDA5-DM. Concomitant infection is a common complication of MDA5-DM. The proper evaluation of patients with MDA5-DM requires knowledge of the disease heterogeneity and clinical course variability. Several biomarkers, including serum levels of anti-MDA5 antibodies and biomarkers related to macrophage activation, have been identified as useful tools for monitoring disease activity and prognosis. MDA5-DM shows a poor response to conventional glucocorticoid and immunosuppressant therapy and has a poor overall prognosis. Therefore, there is an urgent need to explore the key pathogenic mechanisms of MDA5-DM and develop novel therapeutic options for patients. This Review discusses recent clinical progress and pathogenic findings of MDA5-DM.

MDA5-autoimmunity and Interstitial Pneumonitis Contemporaneous with the COVID-19 Pandemic (MIP-C)

Background

Anti-MDA5 (Melanoma differentiation-associated protein-5) positive dermatomyositis (MDA5 + -DM) is characterised by rapidly progressive interstitial lung disease (ILD) and high mortality. MDA5 senses single-stranded RNA and is a key pattern recognition receptor for the SARS-CoV-2 virus.

Methods

This is a retrospective observational study of a surge in MDA5 autoimmunity, as determined using a 15 muscle-specific autoantibodies (MSAs) panel, between Janurary 2018-December 2022 in Yorkshire, UK. MDA5-positivity was correlated with clinical features and outcome, and regional SARS-CoV-2 positivity and vaccination rates. Gene expression patterns in COVID-19 were compared with autoimmune lung disease and idiopathic pulmonary fibrosis (IPF) to gain clues into the genesis of the observed MDA5 + -DM outbreak.

Results

Sixty new anti-MDA5+, but not other MSAs surged between 2020-2022, increasing from 0.4% in 2019 to 2.1% (2020), 4.8% (2021) and 1.7% (2022). Few (8/60) had a prior history of confirmed COVID-19, peak rates overlapped with regional SARS-COV-2 community positivity rates in 2021, and 58% (35/60) had received anti-SARS-CoV-2 RNA vaccines. Few (8/60) had a prior history of COVID-19, whereas 58% (35/60) had received anti-SARS-CoV-2 RNA vaccines. 25/60 cases developed ILD which rapidly progression with death in 8 cases. Among the 35/60 non-ILD cases, 14 had myositis, 17 Raynaud phenomena and 10 had dermatomyositis spectrum rashes. Transcriptomic studies showed strong IFIH1 (gene encoding for MDA5) induction in COVID-19 and autoimmune-ILD, but not IPF, and IFIH1 strongly correlated with an IL-15-centric type-1 interferon response and an activated CD8+ T cell signature that is an immunologic hallmark of progressive ILD in the setting of systemic autoimmune rheumatic diseases. The IFIH1 rs1990760TT variant blunted such response.

Conclusions

A distinct pattern of MDA5-autoimmunity cases surged contemporaneously with circulation of the SARS-COV-2 virus during COVID-19. Bioinformatic insights suggest a shared immunopathology with known autoimmune lung disease mechanisms.

Environmental exposures as risk factors for idiopathic inflammatory myopathies

Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of rare autoimmune diseases, with increasing incidence rates observed in the recent years. The pathogenesis of IIM remains not fully understood, and the interaction of genetic and environmental factors is suspected. It is unclear whether the observed upward trend in the IIM incidence is solely due to improved access to effective diagnostics or perhaps due to increased exposure to external risk factors. The PUBMED database was thoroughly searched for articles describing environmental exposures potentially triggering the onset of IIM. The article summarizes the current knowledge available on this subject, taking into account various environmental factors, including among others UV radiation, infectious agents with SARS-CoV-2, inhaled particles, or iatrogenic effects. Limitations and unmet needs requiring further studies were highlighted.

A systematic review of the incidence, management and prognosis of new-onset autoimmune connective tissue diseases after COVID-19

A literature review on new-onset autoimmune connective tissue diseases (ACTDs) following COVID-19 is lacking. We evaluated potential associations between COVID-19 and the development of new-onset ACTDs. The "population" was adults with disease terms for ACTDs, including systemic lupus erythematosus (SLE), Sjogren's syndrome, systemic sclerosis (SSc), idiopathic inflammatory myositis (IIM), anti-synthetase syndrome, mixed CTD and undifferentiated CTD, and "intervention" as COVID-19 and related terms. Databases were searched for English-language articles published until September 2022. We identified 2236 articles with 28 ultimately included. Of the 28 included patients, 64.3% were female, with a mean age was 51.1 years. The USA reported the most cases (9/28). ACTD diagnoses comprised: 11 (39.3%) IIM (including four dermatomyositis); 7 (25%) SLE; four (14.3%) anti-synthetase syndrome; four (14.3%) SSc; two (7.1%) other ACTD (one lupus/MCTD overlap). Of eight, four (14.3%) patients (including that with lupus/MCTD) had lupus nephritis. The average time from COVID-19 to ACTD diagnosis was 23.7 days. A third of patients were admitted to critical care, one for treatment of haemophagocytic lymphohistiocytosis in SLE (14 sessions of plasmapheresis, rituximab and intravenous corticosteroids) and nine due to COVID-19. 80% of patients went into remission of ACTD following treatment, while three (10%) patients died-one due to macrophage activation syndrome with anti-synthetase syndrome and two from unreported causes. Our results suggest a potential association between COVID-19 and new-onset ACTDs, notably in young females, reflecting more comprehensive CTD epidemiology. The most common diagnosis in our cohort was IIM. The aetiology and mechanisms by which ACTDs emerge following COVID-19 remain unknown and require further research.

Cutaneous Manifestation in COVID-19: A Lesson Over 2 Years Into the Pandemic

Cutaneous manifestations related to Coronavirus Disease-19 (COVID-19) have been reported over 2 years since the pandemic began. This research aimed to review articles published in English that describe cutaneous manifestations related to COVID-19/SARS-CoV-2. A data search for case reports, original studies, and review articles from the onset of the current COVID-19 pandemic to December 31, 2022, was performed using PUBMED, Cochrane Library, ResearchGate, and Google search engines. Keywords were "coronavirus", "novel coronavirus 2019", "COVID-19", "SARS-CoV-2", and "2019-nCoV" in combination with "cutaneous", "skin" and "dermatology" The extracted data included authors, region, sex, age, number of participants with skin signs, cutaneous signs, its location, symptoms, extracutaneous/associated symptoms, suspected or confirmed status for COVID-19, timeline, and healing duration. Six authors independently reviewed the abstracts and full-texts to identify publications providing these details concerning cutaneous manifestations related to COVID-19. A total of 139 publications with full text (122 case reports, 10 case series, and 7 review articles) that reported cutaneous manifestations were identified, and reviewed from 5 continents. The most common cutaneous manifestations of COVID-19 were maculopapular, followed by chilblain-like lesion, urticarial, livedoid/necrotic, vesicular, and other/non-descript rashes/skin lesions. After 2 years into the COVID-19 pandemic, we can conclude that there is no pathognomonic cutaneous manifestation of COVID-19, since it can be also found in other viral infections.