REFERRAL BEHAVIOUR OF PRIMARY CARE DOCTORS TO RHEUMATOLOGY CLINIC IN MALAYSIA

BackgroundThe workload at rheumatology clinics have been growing relentlessly and an audit on new.referrals helps to identify referral behaviour of primary care doctors and improvement can be done by providing further training.ObjectivesTo audit on new referral cases to rheumatology clinic from 2020-2022 and to identify new cases with misdiagnosis for future training purpose.MethodsThis was a retrospective study. The medical records of all new referral to rheumatology clinic Hospital Sultan Ismail and Hospital Pakar Sultanah Fatimah from 1st January 2020 to 31th November 2022 were reviewed. The referral diagnosis and final diagnosis were identified and analysed.ResultsThere were total of 927 new cases referral throughout the 35 months during Covid-19pandemic. Majority of them were diagnosed to have rheumatoid arthritis (217/927)followed by systemic lupus erythematosus (190/927), psoriatic arthritis (147/927),gout (62/927), osteoarthritis (58/927), systemic sclerosis (25/927), ankylosing spondylitis (25/927), soft tissue rheumatism (24/927), Sjogren syndrome (24/927),mixed connective tissue disease (14/927), vasculitis (11/927), fibromyalgia (10/927),polymyositis (7/927) and miscellaneous (39/927).45 out of the new cases were diagnosed as unlikely rheumatic diseases. There were 29pending cases awaiting final diagnosis.212 of the referrals were identified as misdiagnosis with the highest as nodal osteoarthritis.(55/212) followed by unlikely rheumatic disease (43/212), soft tissue rheumatism (24/212),psoriatic arthritis (20/212), Sjogren syndrome (14/212), gout (8/212), rheumatoid arthritis (7/212), fibromyalgia (6/212), systemic lupus erythematosus (5/212), ankylosing spondylitis (4/212), mixed connective tissue disease (3/212), systemic sclerosis (2/212), polymyositis (2/212) and others (19/212): diffuse idiopathic skeletal hyperostosis, hypermobility syndrome, RS3PE syndrome, idiopathic uveitis, graft versus host disease, juvenile idiopathic arthritis, antiphospholipid syndrome, hypothyroidism, post streptococcal arthritis, prolapsed intervertebral disc, cerebrovascular disease, traumatic sternoclavicular joint subluxation, ledderhose disease, paraspinal muscle spasm and viral myalgia).ConclusionNodal osteoarthritis and soft tissue rheumatism can be great mimicker for inflammatory.arthritis and if wrongly diagnosed will lead to unnecessary anxiety or wrong treatment. More training is needed to improve clinical skills amongst primary care doctors.ReferencesNA.Acknowledgements:NIL.Disclosure of InterestsNone Declared.

CLINICAL CHARACTERISTICS OF PEDIATRIC PATIENTS WITH RHEUMATIC DISEASES UNDER TREATMENT WITH BIOLOGICAL THERAPY: INFORMATION FROM BIOBADAMEX

BackgroundThe advent of biologic treatment (bDMARD) in childhood rheumatic diseases (RD) has changed their evolution and prognosis. Evidence is robust for diseases such as juvenile idiopathic arthritis (JIA) and systemic lupus erythematosus (SLE), but in other diseases we still have to learn which is the ideal therapy, time to discontinuation and the potential adverse events (AE) in short and long term.ObjectivesIdentify the clinical and treatment characteristics of pediatric patients with rheumatic diseases with bDMARD treatment and describe the development of AE.MethodsBIOBADAMEX is a prospective ongoing cohort of Mexican patients with RD using bDMARDs since 2016. We included all patients younger than 18 years of age registered in BIOBADAMEX. Descriptive statistics were used for the baseline characteristics and the Chi-square test to analyze the differences between the characteristics of the groups in relation to the development of AE.ResultsA total of 45 patients were included, 31 (69%) of them female, mean age of 13.3 (±3.6) years. (Table 1).The most frequent diagnosis was JIA 25 (56%), followed by SLE 9 (20%), uveitis 5 (11%), polymyositis/dermatomyositis and hidradenitis 2 (4%) respectively;systemic sclerosis and CINCA 1 patient (2%) respectively. The mean duration disease in years was 4.67 (±2.1). Nine patients (20%) used a biologic prior to the current;23 (51%) patients had comorbidities.The most frequent bDMARDs used was Adalimumab (ADA) in 17 (38%) patients followed by Rituximab in 15 (33%) and Tocilizumab in 10 (22%), Infliximab, Abatacept and Canakinumab were used in one patient respectively.When compared by groups, ADA and Tocilizumab were the most used bDMARDs in JIA, Rituximab the only one used in SLE and PM/DM, and ADA the only one for uveitis.15 patients discontinued biological treatment, 4 (27%) due to AE. 82% used an additional synthetic DMARD, being methotrexate the most used in 48% of patients. Steroids were used by 21 (47%) of the patients with a median dose of 10mg (IQR 5 - 25).Fifteen AEs were recorded: 7 (47%) were infections, 5 of these (71%) were COVID;allergies and neutropenia in 2 (13%) patients respectively. By disease infections were more frequent in patients with JIA and Uveitis;neutropenia only occurred in patients with JIA (p 0.95). 87% of the AEs were non-serious, 1 patient with JIA presented a severe AE and one patient with SLE a fatal AE associated with COVID (p 0.93), with no statistically significant difference between groups.ConclusionJIA is the most frequent indication to use bDMARD as worldwide reported. The AE in this analysis are similar to previous registries in terms of the prevalence of infections, in our group the most frequent infectious complication was COVID, being fatal in one patient related with rituximab in SLE. Our study did not find statistically significant differences in the development of AE between diseases;however, they will continue to be reported and the number of patients in the registry will increase.References[1] Sterba,Y.et al. Curr Rheumatol Rep 2016;18,45[2] Fuhlbrigge RC, et al. 2021;47(4):531-543.Table 1.Baseline CharacteristicsBaseline characteristics (n = 45)n%Female, n(%)3168.9Age, media (SD)13.3 (±3.6)Index Body Mass, media (SD)19.6 (±4.9)Dx n(%)n %- JIA25 55.6- SLE9 20- PM/DM2 4.4- Uveitis5 11.1- Hidradenitis2 4.4- Systemic sclerosis1 2.2- CINCA1 2.2Disease duration(years) media (IQR)4.67±2.1Current treatment n(%)n %- Infliximab1 2.2- Adalimumab17 37.8- Rituximab15 33.3- Abatacept1 2.2- Tocilizumab10 22.2- Canakinumab1 2.2Treatment duration (months) median (IQR)4.5 (0.56 – 36.9)Treatment suspension, n(%)15 (33.2)Months to suspension, median (IQR)0.66 (0.46 – 1)Discontinue cause, n(%)n %- Inefficacy1 6.6- Remission1 6.6- Side effects4 26.6- Others5 33.3- Unknown4 26.6Steroids use, n(%):21 46.7Steroids dose (mg), median (IQR)10 5 – 25DMARDs use n(%):37 82.2AE, n(%):15 33.3By disease:AE TypeInfectionAllergyNeutropeniaOtherChi2JIA31230.95SLE1101Uveitis3000Acknowledgements:NIL.Disclosure of InterestsSamara Mendieta: None declare , Alfonso Torres: None declared, Fedra Irazoque-Palazuelos: None declared, Sandra Sicsik: None declared, Iris Jazmin Colunga-Pedraza: None declared, Daniel Xavier Xibille Friedmann: None declared, Deshire Alpizar-Rodriguez Employee of: Scientific advisor in GSK-Mexico, VIJAYA RIVERA TERAN: None declared.

CYCLOPHOSPHAMIDE THERAPY DURING THE COVID19 PANDEMIC

BackgroundDuring the Coronavirus disease (COVID-19) pandemic, one of the biggest concerns of rheumatologists and rheumatology patients has been whether the risk or severity of the disease will increase with immunosuppressive therapy. Some drugs have been reported to be associated with adverse Covid19 outcomes [1,2]. Cyclophosphamide (CYC) is a drug that has been used in rheumatology practice for many years. There is not enough data in the literature on the frequency or consequences of COVID-19 while receiving CYC therapy.ObjectivesThe aim of this study is to examine the frequency and outcomes of Covid19 in patients who received CYC therapy during the Covid19 pandemic.MethodsThe files of patients who received CYC therapy protocol between March 2020 and March 2022 at Başkent University Faculty of Medicine Ankara Hospital, Rheumatology outpatient clinic were retrospectively reviewed. In our clinic, CYC therapy is administered as an intravenous treatment protocol of 500 mg three times every 10 days, then 500 mg every two weeks. Although the cumulative dose varies depending on the disease and the patient, it is usually planned to be at least three gram. The diagnosis of Covid 19 was made in the patients with clinically compatible radiology and SARS-CoV-2 PCR test results.ResultsA total of 36 patients received CYC during the specified period. CYC indications were ANCA-associated vasculitis in 12 patients, interstitial lung disease associated with undifferentiated connective tissue disease in 5 patients, SLE in 5 patients, scleroderma in 4 patients, Sjögren's syndrome in 4 patients, Behçet's disease in 1 patient, vasculitis associated with sarcoidosis in 1 patient, rheumatoid vasculitis in 1 patient, leukocytoclastic vasculitis in 1 patient, polymyositis in 1 patient and Takayasu disease in 1 patient.The median age (q1-q3) was 62 (52-68) years. Covid19 infection was detected in only 3 patients (8%) during the CYC therapy protocol. The median cumulative CYC dose for these patients was 3.5 g. One out of 3 patient was hospitalized for Covid 19 pneumonia. There was no death due to Covid19.ConclusionIn this study, it has been shown that CYC therapy was safe during the Covid19 pandemic period.References[1]Samanta J, Naidu G, Deo P, Mittal S, Prasad CB, Das D, Dhir V, Sharma SK, Ramachandran R, Rathi M, Nada R, Minz RW, Jain S, Sharma A. Managing ANCA-associated vasculitis during COVID-19 pandemic: a single-center cross-sectional study. Rheumatol Int. 2022 Dec;42(12):2159-2166.[2]Singh N, Madhira V, Hu C, Olex AL, Bergquist T, Fitzgerald KC, Huling JD, Patel RC, Singh JA. Rituximab is associated with worse COVID-19 outcomes in patients with rheumatoid arthritis: A retrospective, nationally sampled cohort study from the U.S. National COVID Cohort Collaborative (N3C). Semin Arthritis Rheum. 2023 Feb;58:152149.Acknowledgements:NIL.Disclosure of InterestsNone Declared.

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.

Flares Following Covid-19 Vaccination in Patients with Idiopathic Inflammatory Myopathies: Combined Analysis from the Covid-19 Vaccination in Autoimmune Diseases (Covad) Studies

Background/Aims Flares following COVID-19 vaccination are an emerging concern among patients with rare rheumatic disease like idiopathic inflammatory myositis (IIMs), whereas data and understanding of this is rather limited. We aimed to study the prevalence, characteristics and determinants of IIM flares following COVID-19 vaccination. Methods CoVAD (COVID-19 Vaccination In Autoimmune Diseases) surveys are global patient self-reported e-surveys from 109 countries conducted in 2021 and 2022. Flares of IIM were defined by 4 definitions;a. patient self-reported, b. physician and immunosuppression (IS) denoted, c. sign directed (new erythematous rash, or worsening myositis or arthritis), d. MCID worsening of PROMISPF10a score between the patients who had taken both surveys. Descriptive statistics and multivariate regression were used to describe the predictors of flare. Cox-regression analysis was used to differentiate flares by IIM subtypes. Results Among the 1,278 IIM patients, aged 63 (50-71) years, 276 (21.5%) were dermatomyositis, 237 (18.5%) IBM, 899 (70.3%) were female and most were Caucasian (80.8%). Flares of IIM were seen in 123/1278 (9.6%), 163/1278 (12.7%), 112/1278 (8.7%), and 16/96 (19.6%) by definitions a-d respectively with median time to flare being 71.5 (10.7- 235) days. Muscle weakness (69.1%), and fatigue (56.9%) were the most common symptoms of flare. The predictors of self-reported flare were: inactive/disease in remission prior to first dose of vaccine (OR=4.3, 95%CI=2.4-7.6), and anxiety disorder (OR=2.2, 95%CI=1.1-4.7). Rituximab use (OR=0.3, 95%CI=0.1-0.7) and IBM (OR=0.3, 95%CI=0.1-0.7) were protective. Physician defined flares were seen more often in females, mixed ethnicity, and those with asthma, ILD, and anxiety disorder (OR ranging 1.6-7.0, all p<0.05). Notably, overlap myositis (OM) had higher HR for flare compared to polymyositis (HR=2.3, 95%CI=1.2-4.4, p=0.010). Conclusion Nearly one in ten individuals with IIM develop flares after vaccination, more so among women, those with overlap myositis, and inactive disease prior to vaccination. Formal definition of flares in IIM is needed.

Covid-19 Booster Vaccine Related Dermatitis: A Case Study

Case Report: A 28 year old male with a past medical history of hypothyroidism and positive ANA presented to an outpatient dermatology clinic with a diffuse pruritic rash two weeks after the administration of his first Moderna COVID booster vaccine. He denied any other accompanying symptoms such as fever or chills as well as any similar rashes to prior doses of the Moderna COVID vaccine. The rash consisted of pink erythematous minimally scaly papules, thin plaques and patches involving the left and right dorsal hands, forearms, wrists, face, neck and left shoulder. The remainder of the patient's skin including the bilateral lower extremities, the eyelids, conjunctiva and oral mucosa was clear. The patient denied any similar rashes in the past. The patient denied any allergies to medications, or food or environmental allergies. He denied any notable contact allergen exposures, including to soaps, lotions, and cosmetic products. The patient also denied any significant family history or past surgical history. The patient was on Armour Thyroid for hypothyroidism and testosterone for low levels since age eighteen. The patient was started on cetirizine 10 mg once daily for the rash with minimal improvement. Autoimmune workup for the rash was notable for an elevated anti-RNP and as the patient's past medical history included Raynaud's phenomenon and ANA positivity for ten years, the patient was diagnosed with mixed connective tissue disease (MCTD). Autoimmune conditions can often have an indolent course, where symptoms progressively develop and worsen. MCTD is an autoimmune overlap syndrome that can consist of the following three connective tissue diseases: systemic lupus erythematosus, scleroderma, and polymyositis. Millions of individuals across the world are receiving COVID vaccines to protect themselves and members of their community, and it is of utmost importance that we continue to investigate adverse events. Although of low incidence, these rare effects have the ability to impact large numbers of people within both healthy and immunocompromised populations. It is critical that we examine and document them in a rigorous manner, to ensure safe vaccine delivery and reassure the public about vaccine safety overall.

Post-COVID-19 Polymyositis: A Case Report.

Post-Coronavirus disease 2019 (COVID-19) development of polymyositis is rare, with very few cases documented in the literature. In patients developing vague symptoms after recovery from COVID-19, it is important to investigate all avenues, including the possibility of polymyositis. Polymyositis is typically characterized as symmetrical muscle weakness and histological, electrical, and chemical evidence of muscle injury. Patients identified can be treated with immunosuppressants to return some quality of life and prevent disease progression. In this report, we describe a 58-year-old Caucasian male who presented with symptoms of weakness, myalgias, and arthralgias, six months after recovering from flu-like symptoms of COVID-19. The patient was tested for other autoimmune etiologies and myopathies without positive results. He was treated with prednisone and reported moderate improvement in symptoms. Unfortunately, the patient declined a muscle biopsy or electromyographic testing. According to the criteria for polymyositis set by the Myositis Association and the response to therapy, the patient's symptoms pointed to a likely diagnosis of post-COVID-19 polymyositis.

Hypogammaglobulinemia after Rituximab Treatment in an Italian Real-Life Cohort of Iim

Background. Rituximab (RTX) is a chimeric monoclonal antibody that binds the CD20 molecule on the surface of B cells and leads to B cell depletion. RTX is recommended by the European League Against Rheumatism (EULAR) as off-label in patients affected by idiopathic inflammatory myopathies (IIM). The real-world experience has shown that hypogammaglobulinemia occurring early after anti-CD20 treatment can be multifactorial (active disease, effect of other drugs) and usually transient, with a minimal increase in the risk of infections. The present study aimed to analyse the differences in the rate of RTX-associated hypogammaglobulinemia in a cohort of IIM patients in clinical practice, as well as the onset of major infections and its correlation with hypogammaglobulinemia. Methods. Patients followed at Rheumatology Unit of Siena University Hospital from January 2020 to September 2021 were retrospectively enrolled. Inclusion criteria were as follows: fulfilment of disease-specific classification criteria 2017 EULAR criteria and /or Peter and Bohan criteria for dermatomyositis (DM) and polymyositis (PM), positivity of anti-synthetase antibody and typical clinical features for anti-synthetase syndrome (ASS) and the measurement of serum Ig levels at the time of RTX administration (maximum 2 weeks before) (T0) and 6 (T1) to 12 (T2) months later, consistently with previous studies. Ig serum levels, measured by standard nephelometry (normal ranges: IgG 700-1600 mg/dL, IgM 40-240 mg/dL, IgA 70-400 mg/dL) were assessed as part of routine clinical care. Hypogammaglobulinemia was defined as moderate (serum IgG <600 mg/dL) and severe (IgG <400 mg/dL), as previously reported. Results. Seven patients (mean+/-SD, 57.3+/-19.7 years;7 female) were enrolled. Three of them had diagnosis of DM, three ASS and one PM. Two patients showed MDA5-positivity, two JO1-positivity, one TIF1-gamma-positivity, one PL7-positivity and the other one PM/Scl-positivity. All patients had at least two organs involved, and 4 out of 7 (57%) suffered from interstitial lung disease. Before starting RTX treatment, three and four patients underwent at least one and two synthetic immunosuppressants. All patients underwent low dosage of corticosteroids, and four patients underwent concomitant synthetic immunosuppressants (2 hydroxychloroquine and 2 MTX). IgG concentrations were statically lower at T2 compared to those at baseline (p=0.0391). None of them showed severe hypogammaglobulinemia. Similarly, IgM concentration significantly decreased at T2 compared to those at baseline (p=0.0078). Two patients showed major infections and two patients had paucisymptomatic COVID-19 (one of them had twice). Corticosteroids dosages were inversely correlated with IgG T2 concentrations (p=0.040, r=-0.919). Conclusion. Hypogammaglobulinemia following RTX is uncommon in IIM and is more likely in patients with high glucocorticoids, immunosuppressants and CYC exposure. IgG monitoring at least 6 months after RTX treatment may be useful in stratifying patients to identify those who require closer monitoring. These results shine a spotlight for increased awareness of the role of immunoglobulin measurement before maintenance doses of RTX.

Impaired Promis Physical Function in Idiopathic Inflammatory Myopathy Patients: Results from the Multicenter Covad Patient-Reported E-Survey

Background. Evaluation of physical function is fundamental in the management of idiopathic inflammatory myopathies (IIMs). Patient-Reported Outcome Measurement Information System (PROMIS) is a National Institute of Health initiative established in 2004 to develop patient-reported outcome measures with improved validity and efficacy. The present study aims to investigate the physical function status of IIM patients compared to those with non-IIM autoimmune diseases (AIDs) and healthy controls (HCs) utilizing PROMIS Physical Function (PF) data obtained in the coronavirus disease-2019 (COVID-19) Vaccination in Autoimmune Diseases (COVAD) study, a large-scale, international self-reported e-survey assessing the safety of COVID-19 vaccines in AID patients. Methods. The survey data regarding demographics, IIM and AID diagnosis, disease activity, fatigue and pain VAS, and PROMIS PF short form-10a were extracted from the COVAD study database. The disease activity (active vs inactive) of each patient was assessed in 3 different ways: (1) physician's assessment (active if there was increased immunosuppression), (2) patient's assessment (active vs inactive as per patient), and (3) current steroid use. These 3 definitions of disease activity were applied independently to each patient. PROMIS PF-10a scores were compared between each disease category (IIMs vs non-IIM AIDs vs HCs), stratified by disease activity based on the 3 definitions stated above, employing negative binomial regression model, and the predicted PROMIS PF-10a score adjusted for age, gender, and ethnicity was calculated. Factors affecting PROMIS PF-10a scores other than disease activity were identified by multivariable regression analysis in the patients with inactive disease (IIMs or non-IIM AIDs). The association between fatigue or pain VAS and PROMIS PF-10a scores was also assessed. Results. 1057 IIM patients, 3635 non-IIM AID patients, and 3981 HCs responded to the COVAD survey until August 2021. The median age of the respondents was 43 [IQR 30-56] years old, and 74.8% were female. Among IIM patients, dermatomyositis was the most prevalent diagnosis (34.8%), followed by inclusion body myositis (IBM) (23.6%), polymyositis (PM) (16.2%), anti-synthetase syndrome (11.8%), overlap myositis (7.9%), and immune-mediated necrotizing myopathy (IMNM) (4.6%). The predicted mean of PROMIS PF-10a scores was significantly lower in IIMs compared to non-IIM AIDs or HCs (36.3 [95% (CI) 35.5-37.1] vs 41.3 [95% CI 40.2-42.5] vs 46.2 [95% CI 45.8-46.6], p<0.001), irrespective of disease activity (Figure 1). The results were consistent across analyses using different disease activity definitions (physician's assessment, patient's assessment, and steroid use), while the largest difference between active IIMs and non-IIM AIDs was observed when the disease activity was defined by patient's assessment (35.0 [95% CI 34.1-35.9] vs 40.1 [95% CI 38.7-41.5]). Considering the subgroups of IIMs, the scores were significantly lower in IBM in comparison with non-IBM IIMs (p<0.001). The independent factors associated with low PROMIS PF-10a scores in the patients with inactive disease were older age, female gender, and the disease category being IBM, PM, or IMNM. Higher fatigue or pain VAS was associated with lower PROMIS PF-10a scores in each disease category (p<0.001), while the scores were still lower in IIMs compared to non-IIM AIDs even after being adjusted for fatigue and pain. Conclusion. Physical function is significantly impaired in IIMs compared to non-IIM AIDs or HCs, even in patients with inactive disease. The elderly, women, and IBM groups are the worst affected, suggesting that developing targeted strategies to minimize functional disability in certain groups may improve patient-reported physical function and disease outcomes.

Unusual Myositis of the Temporalis Muscle Occurring with Acute Covid-19

Background. SARS-CoV-2 infection can be accompanied by neuromuscular disorders. Rhabdomyolysis and Guillain-Barre syndrome have been described repeatedly. There are case reports of inflammatory myopathies manifesting during COVID-19, presenting as dermatomyositis, polymyositis or immune-mediated necrotizing myopathy, with dermatomyositis-like presentations most commonly reported. Larger cases series are from postmortem examinations of COVID-19 patients, where variable inflammatory pathology of the skeletal muscle has been found frequently but without local detection of the actual virus. Thus, autoimmune mechanisms or the systemic interferon response are discussed as causes. We report a case of focal inflammatory myopathy with perimysial pathology of the temporalis muscle occurring with acute, but mild COVID-19. Methods. Case report of clinical observations, cranial MRI, histopathological, and laboratory findings. 3T cranial MRI was performed with gadolinium contrast. Open temporalis muscle biopsy was performed. The sample underwent standard cryohistological studies as well as immunohistochemistry with antibodies against MHC-I and II, CD3, CD4, CD19, CD68, anti-MAC, p62 and MxA. Testing for auto-antibodies was based on immunoblots or ELISA. RT-PCR for SARS-CoV-2 was run with RNA extracted from cryopreserved muscle. Results. A Caucasian woman in her 60s with no history of autoimmune or muscle complaints developed swelling and pain of the right jaw musculature five days after testing positive for SARS-CoV-2 due to respiratory tract symptoms. In addition, she experienced trismus, but no further neuromuscular complaints. The course of respiratory tract symptoms stayed mild. She had been vaccinated previously with single shot SARS-CoV-2 vector vaccine. Due to persistent swelling and complaints, giant cells arteritis was excluded by unresponsiveness to five days oral steroids and sonography of the temporal artery. Cranial MRI was performed nearly four weeks after the SARS-CoV-2 infection and showed marked swelling and oedema of the temporalis muscle. Its biopsy showed numerous CD68 and acid phosphatase positive cells infiltrating from perimysial perivascular foci towards the endomysium with perimysial damage but little damage of adjacent, perifascicular muscle fibres. Muscle fibres did not react with anti-MHC-II, anti-MAC or -MxA. Capillaries did not react with anti-MAC or -MxA. SARS-CoV-2 RNA was not detected in muscle tissue. Serum creatine kinase was not elevated in the subacute phase. Slightly elevated ANA titre led to detection of autoantibodies against proliferating cell nuclear antigen (PCNA). No pathological results for other autoantibodies, including myositis-specific antibodies and anti-ds-DNA, were found in blood. Neither were antibodies against hepatitis C and B viruses. Retesting 15 weeks after infection, anti-PCNA immunoblot was still positive, but ELISA did not indicate a pathologic titre. The swelling, myalgia and trismus regressed spontaneously a month after onset, yet the latter still persists at the time of reporting. Conclusion. Our case diverges from the majority of COVID-19 associated my-ositis reports in the unusual location of the focal myositis and the histopathological pattern of predominantly perimysial damage and histiocytic infiltration. It concurs with the literature as no SARS-CoV2 RNA could be detected in the muscle. Anti-PCNA is associated very rarely with myositis. Other associated disorder (systemic lupus erythematosus, chronic viral hepatitis B or C) were not found. Increased levels of autoantibodies are reported in COVID-19 and mostly attributed to loss of self-tolerance during the acute disease phase. Interestingly, the structural protein M of SARS-CoV-2 appears to interact notably with PCNA in infected cells. Still, the causal connection between the myositis and COVID-19 in this case is based on the close temporal association in the absence of alternative, competing explanations from the medical history and findings.

Kaiser Permanent (Kp) Mid-Atlantic States (Mas) Experience with Covid Related Hospital Admissions in Adult Patients with Myositis

Background. Myositis is a group of rare systemic disease and may be treated with immunosuppressives which increase the risk for poor outcome with the COVID19 pandemic. Patients with this condition may have higher rates of admission to the hospital. Methods. KP is a health insurance plan and provides care to about 800 thousand people (including Medicare and Medicaid population) in Maryland, District of Columbia and Northern Virginia. As part of quality improvements, we randomly looked at 40 patients from our larger cohort with myositis who are diagnosed and followed by a board-certified rheumatologist. We noted hospitalizations and Covid infection from March 1, 2020 to December 31, 2021. Results. Of the 40 patients, 29 (72%) were female and 11 were male. 19 (47%) were Blacks, 18 whites (including 6 Latino), and 3 Asians. Age ranged from 25 to 80 years with a mean age of 59.6 years. 25 (62%) patients had Dermatomyositis, 14 had polymyositis and 1 was IBM. The mean age at diagnosis was 55.9 years (range 23-80 years). 12 (30%) had myositis specific antibodies (4 Jo-1, 4 Mi-2, 1 PL 7, 1 PL 12, 1 PL7 plus PL12, 1 TIF Gamma). 22 (55%) were negative. Six did not have antibody testing. During this time, 11 (27.5%) were admitted to the hospital, 2 patients tested positive for COVID 19. One tested positive in the hospital and was asymptomatic. The other person was admitted for symptomatic COVID 19 infection. Other reasons for admission were cardiac, pulmonary (noncovid 19 related), infections, Gastrointestinal issues (including GI bleeding). One admission was for accidental bleach ingestion, and one for psychiatric admission. Of these 40 patients, 38 (95%) patients have received the COVID vaccinations, one patient refused, and for one person we do not have any record of vaccination. Conclusion. The admission rates to the hospital do appear to be higher for this group of patients with myositis, as is generally postulated. However, the reasons for admission were largely related to reasons other than COVID 19 infection and were related to general medical conditions.

Dutch Myositis Working Group (Dmwg)

Introduction. The poster of the Dutch Myositis Working Group (DMWG) aims to inform people about her goals, activities and ambitions. The group is run by seven patients, representing all types of myositis, supported by Spierziekten Nederland, the umbrella patient organization for neuromuscular disorders in The Netherlands and 4 myositis specialists as medical advisors. Chair: Ingrid de Groot. Contact email: myositis@spierziekten.nl Goals and ambitions of the Dutch myositis working group: * I n collaboration with medical advisors to provide information about IIM (idiopathic inflammatory myopathies) or myositis to newly diagnosed patients and their families: IIM types, symptoms, diagnosis, (new) treatment options, prognosis, inform them about the myositis expertise centres etc. * To connect and support people with all types of IIM: dermatomyositis (DM), polymyositis (PM), Anti Synthetase Syndrome (ASyS), immune mediated necrotizing myopathy (IMNM), juvenile dermatomyositis (JDM), overlap myositis. * To raise awareness of myositis among the public, health care professionals and researchers, pharmaceutical companies? * To collaborate with clinicians, researchers and funds on a national and international level with the aim to improve (clinical) care and research. * To stimulate and participate in the development and conducting of clinical trials. * To collaborate with myositis working groups and patient organisations abroad. * To represent the patient perspective within in the Myositis Network Netherlands and (inter)national myositis study groups. * Patient advocacy. Activities and services: * In person or online meetings aiming to offer moral support and an opportunity to share experiences, concerns etc. or just to socialize. Three times a year we organize separate meetings for people with IBM, for people with other IIM and for caregivers. * Website updates on treatment, guidelines, (inter)national research, activities and actualities (e.g. Covid situation). * Supply patients with brochures for GP/ family doctor, physiotherapist etc. * Online (secured) platform for members. * Annual patient conference with diagnosis specific scientific programs. * Monthly newsletters: these are personalized which means they contain mainly news on the receivers type of IIM (e.g. IBM or ASyS) and information on general topics concerning all people with IIM or neuromuscular disorder. * In person meetings and / or online webinars on general topics e.g. living with a chronic condition, work, pain, fatigue. * Annual meetings with medical advisors: the working group pays a visit to all medical advisors in their respective hospitals. * Representation at (inter)national conferences. * Representation in projects such as guidelines development. * Collaboration in (inter)national studies leading to enrolling Dutch patients, researchers and clinicians in multi-centre studies, (co-) authorships in publications and to presentations during conferences (Treat NMD, IMACS, MNN). * To advise and recommend on research proposals from patient perspective. * To advise decision makers on continuation of expert centres from patient perspective. Collaborations: * Myositis Network Netherlands: patient representation on the board. * OMERACT (Outcome Measures in Rheumatology): Patient Research Partner of the Myositis Working Group. * IMACS (International Myositis Assessment and Clinical Studies Group): steering committee member of Exercise & Rehabilitation Group, led by Helene Alexanderson, ass.prof PhD, RPT). * ENMC (European Neuromuscular Centre): patient representation in myositis workshops. * EULAR (European League against Rheumatism): member of PARE and Patient Research Partner. * GCOM. * ERN - NMD (European Reference Network for Neuromuscular Diseases): member of NMD working group led by em. prof. dr. Marianne de Visser. * Patient organizations for people living with myositis . We are in this together Since myositis is a (very) rare disease, the 'myositis community' is a small one although we're happy to say that it is expanding quite rapidly. Through our inte sive involvement in several national and international studies and research projects we now have close contacts with many myositis experts across the globe, which makes it easier to keep up with actualities and developments concerning research, treatment etc. and to disseminate this knowledge to our members. This helps us to inform, support and advocate for the Dutch people living with myositis and their families and at the same time it offers opportunities to give something back: by sharing with the research community and clinicians our experiential knowledge of the consequences of myositis on everyday life. That way we can contribute to more meaningful research. We can only go forward if we do this together! That is why we are very ambitious in our efforts to contribute to myositis research. Here we list our collaborative efforts: * In 2019 the Myositis Network Netherlands of clinicians and researchers with expertise in IIM was established in which the DMWG is representing the patient perspective by a member on the board. * In OMERACT Myositis Working Group a member of the DMWG is one of the two Patient Research Partners and as such an equal partner of this study aiming to define a set of core patient reported domains with regard to the quality of life and respective instruments for use in IIM. The involvement of the DMWG has led to the opportunity for Dutch patients to participate in Delphi surveys and to an opportunity for Dutch myositis clinics to collaborate in the longitudinal study that emerged from this. * The IMACS network is an important part of our international network. One of our DMWG members is member of the Executive Committee of the Exercise & Rehabilitation Group and as such can facilitate for Dutch patients to become involved in the current study with the ultimate objective to develop recommendations for exercise in all types of IIM. * Members of the DMWG participated in several ENMC workshops on IIM as patient representatives and will continue to do so in the future. * Through a PARE membership in EULAR and membership of the study group of 'collaborative research' the DMWG hopes to raise awareness of myositis within the influential EULAR community and to speak up on behalf of the patients in Europe living with IIM. * One of our members is member of the GCOM committee responsible for the patient program of GCOM and shares the ambitions of this GCOM committee to increase the involvement of patients in this very important IIM conference. * One DMWG member joined the ERN- Neuromuscular Disease group and as such represents the people with IIM living throughout Europe. * DMWG has ambitions to empower people living with IIM and to connect with them, crossing borders by doing so. We have close and amicable relationships with patient organisations in Australia, Czech Republic, Germany, Sweden, UK and USA. * Empowering patients is one of our goals and we accomplished this for instance in Sweden. On invitation by prof. dr. Ingrid Lundberg our chair visited the Karolinska Institute, spent a week with their myositis team and in return was one of the speakers on the annual patient meeting and helped the Swedish patients establish their own myositis working group.

Myositis Associated with the Anti-COVID-19 Covishield Vaccine

Introduction: The SARS-CoV-2 made the world stop its activities, and the only chance of returning to normal life is the vaccine. But like any vaccination, some complications have been reported. We report the case of a patient who presented a myositis following the administration of the Covishield* (AZD1222, ChAdOx1 nCoV-19, AstraZeneca) COVID-19 vaccine. Case Report: 12 hours after his first dose, an 84-year-old patient presented to us reporting a decrea-sed muscle strength: the patient can move against gravity but not against resistance. The biological assessment showed that CK was at 4,250 IU/L, myoglobin was at 144 microgram/L and aldolases at 16.9 U/L. The patient received high doses of corticosteroids. Discussion(s): The development of vaccines and immunization programs reduced the morbidity and mortality of several diseases. Other case reports suggested the possible association between myopathies and the administration of the hepatitis B vaccine and H1N1 plus the seasonal trivalent influenza and other vaccines. The exact mechanism is still unknown, but a presumable autoimmune phe-nomenon is incriminated. Conclusion(s): The main purpose of this case report is to raise awareness about the possible link between the COVID-19 vaccination and polymyositis and the urge to take charge to avoid further complications.Copyright © 2023 Bentham Science Publishers.

An occurrence of immune-mediated necrotizing myopathy following treatment of polymyositis in a Filipino female: A case report

Background: Necrotizing myopathy has been previously described but was not included in the Peter and Bohan criteria until 2004, when immune-mediated necrotizing myopathy (IMNM) was distinguished from polymyositis (PM) based on immunologic and histopathologic differences. IMNM is currently a well-recognized autoimmune myopathy and represents up to 20% of these cases. Case: A 60-year- old female with biopsy-proven PM achieved sustained clinical remission with Rituximab. Her co-morbid conditions include hypertension, diabetes mellitus, and dyslipidemia. The patient noted a recurrence of gradual progressive, proximal muscle weakness and easy fatigability after receiving her first mRNA Covid-19 vaccine. Four months after onset of symptoms, CK Total was 9600 U/L. Rituximab was administered and muscle weakness and total CK levels (1247 U/L) improved within 10 days. She was prescribed rosuvastatin and fenofibrate for dyslipidemia within 7 days of completing the rituximab course. Two weeks later, proximal muscle weakness recurred. She became wheelchair-bound and experienced dysphonia. MMT score was 2/5 in proximal muscles and total CK total increased to 19,935 U/L. The patient received Methylprednisolone 500 mg IV once a day for 3 days. She had a good response with resolution of dysphonia and improvement of MMT to 4/5 on shoulder abduction and hip flexion on the 6th hospital day. She was discharged on oral methylprednisolone at 1 mg/kg/day. Muscle biopsy was consistent with an immune-mediated necrotizing myopathy, revealing necrotic fibers, intracellular macrophages, fatty infiltrates, irregular staining patterns on NADH stain with no evidence of endomysial inflammation, perifascicular atrophy, ragged red fibers, or rimmed vacuoles. Antibodiy against 3-hydoxy- 3- methylglutarylcoenzymeA reductase (HMGCR) result is pending but the other myositis-specific antibodies are negative.(including anti-SRP). Conclusion(s): IMNM is an autoimmune myopathy associated with anti-HMGCR and anti-SRP antibodies that clinically present similarly to polymyositis. The temporal occurrence of worsening muscle weakness with initiation of statin therapy make statin toxic myopathy or immune mediated necrotizing myopathy as diagnostic considerations. This case emphasizes the need to re-evaluate the etiology of new onset muscle weakness in patients with idiopathic inflammatory myopathy and highlights the role of myositis-specific antibodies and muscle biopsy in confirming the diagnosis.

COVID-19 and Sepsis in an Atypical Case of Mixed Connective Tissue Disorder Presenting With a Myasthenic Crisis.

Myasthenia gravis (MG) is an autoimmune illness that causes neuromuscular junctions to be damaged by anti-acetylcholine receptor antibodies. It is a very rare condition that is more common among women. Fatigable fluctuating diplopia or ptosis is the characteristic early appearance of this condition. Dysphagia or dysphonia may be present in rare cases. This illness can affect any group of skeletal muscles, including those in the neck and upper limbs. It can also affect the muscles that help you breathe, which can lead to breathing failure. We present a case of a 20-year-old female diagnosed with mixed connective tissue disease presenting with acute respiratory failure as the initial presentation of MG. Clinicians have to have a high index of suspicion for myasthenia when patients arrive with fatigable muscle weakness. This will cut down on the amount of money spent on investigations and the risk of morbidity.

POLYMYOSITIS-ASSOCIATED INTERSTITIAL LUNG DISEASE RESPONSIVE TO IV IMMUNOGLOBULIN THERAPY

SESSION TITLE: Critical Diffuse Lung Disease Cases 2 SESSION TYPE: Case Report Posters PRESENTED ON: 10/19/2022 12:45 pm - 01:45 pm INTRODUCTION: Polymyositis (PM) and dermatomyositis (DM) are inflammatory syndromes that have been shown to be associated with interstitial lung disease in up to 64% of cases. Current management strategies for PM/DM-ILD are mostly derived from treatment of PM/DM and rely on the immunomodulatory effects of steroids and steroid sparing medications. Literature supports the use of intravenous immunoglobulins for the management of PM/DM-ILD. However, this stems from isolated case reports. CASE PRESENTATION: Our patient is a 43-year-old female, previously healthy, who was referred to our ILD clinic for evaluation of possible diffuse interstitial lung disease. Her symptoms began May of 2019 with dyspnea, cough, and muscle aches. Her initial workup was significant for reticular opacities in the mid to lower lung fields on x-ray, moderate restriction, and severe diffusion impairment on pulmonary function tests. High resolution CT scan (HRCT) of the lungs showed a radiological pattern suggestive of nonspecific interstitial pneumonitis (NSIP) with mid to lower lung predominant ground glass opacities, mild subpleural reticulation, traction bronchiectasis with no evidence of honeycombing or air trapping. Further workup showed a positive antinuclear antibody (ANA) in a speckled pattern with a titer of 1:320. Her other rheumatological workup was initially largely unremarkable and she denied significant drug/toxin exposure. She was treated with steroids with initial improvement, however had significant clinical deterioration requiring hospitalization and oxygen supplementation and was eventually started on Mycophenolate Mofetil in Aug 2020. Her pulmonary disease remained stable until she was admitted again in Jan 2021 with new hypoxemic respiratory failure requiring 6 L supplemental oxygen. During that admission, she was diagnosed with polymyositis and referred for a lung transplant evaluation, she also started on IVIG for the treatment of active myositis to wean her off steroids prior to transplant listing. She was discharged home and underwent a full transplant workup. She required readmission for worsening hypoxemia now requiring 12 L supplemental oxygen in May 2021, HRCT showed worsening ground glass opacities. She was again treated with IVIG and a steroid course and had near complete resolution of her hypoxia with a 2 L oxygen requirement only on ambulation. She continues to follow up with our interstitial lung disease team and the pulmonary transplant team. Her course has been complicated by multiple admissions with bacterial pneumonia as well as COVID-19 infection. DISCUSSION: Treatment of PM/DM associated ILD relies heavily on the use of steroids as well as steroids sparing agents such as Mycophenolate or Rituximab. IVIG has been implicated in improving underlying lung disease with data derived from case reports. CONCLUSIONS: Our case highlights the importance of further advanced research in this field. Reference #1: Peshbahar, S., & Bendstrup, E. (2020). Remarkable benefits of intravenous immunoglobulin (IVIG) in a patient with polymyositis-associated acute interstitial lung disease. European Clinical Respiratory Journal, 7(1), 1840706. Reference #2: Fathi, M. (2006). Interstitial lung disease in polymyositis and dermatomyositis. Karolinska Institutet (Sweden). DISCLOSURES: No relevant relationships by Hafsa Abdulla No relevant relationships by ALAA ABU SAYF

RHABDOMYOLYSIS AS A VARIANT OF COVID-19 MYOSITIS

SESSION TITLE: Management of COVID-19-Induced Complications SESSION TYPE: Rapid Fire Case Reports PRESENTED ON: 10/19/2022 12:45 pm - 1:45 pm INTRODUCTION: Myalgias are one of the most common manifestations of a COVID infection. Myositis is much less reported with the spectrum of presentation ranging from asymptomatic elevation of creatinine kinase (CK) to rhabdomyolysis. Further understanding is required to formulate evidence based protocols for management and prognostication. CASE PRESENTATION: A 25-year-old male smoker, unvaccinated for COVID presented to the hospital with fever, weakness and myalgias and tested positive for COVID. Examination showed mild tenderness in the proximal muscles of the lower extremities. Labs were significant for metabolic acidosis, hypocalcemia, hyperkalemia, acute kidney injury, AST 6178, ALT 1340, CK > 36000 and CPK > 60000 and gross hematuria. Electrolyte abnormalities were corrected and he received aggressive hydration with intravenous fluids containing bicarbonate. Oxygen requirements increased and he received dexamethasone and Baricitinib for COVID. His creatinine continued to increase despite downtrending transaminases and CK. Ultrasound liver was normal. He developed bilateral pleural effusions and mild ascites suspected secondary to volume overload in the setting of acute renal failure. Hemodialysis was initiated and he received a total of 6 sessions of hemodialysis over the next week. Creatinine, BUN and GFR significantly improved. AntiJo1 Ab ordered to rule out polymyositis was negative. Transaminitis and raised CK levels downtrended alongside the COVID inflammatory markers and oxygen requirements as the patient was weaned to room air. DISCUSSION: The spectrum of COVID myositis reported thus far covers asymptomatic elevation of muscle enzymes, myasthenia, paraspinal myositis, dermatomyositis and rhabdomyolysis (1). The pathophysiology of COVID myositis has been hypothesized to be through ACE2 receptor mediated viral entry into muscle fibers leading to activation of innate and adaptive immunity. Other proposed mechanisms include the release of inflammatory cytokines and molecular mimicry with cross reaction of the antiviral antibodies. Myositis was most reported most commonly among males aged 33–87 (1). Symptoms when present include fevers, cough, shortness of breath, myalgias and proximal, lower limb–dominant, acute, and symmetric weakness. Peak CK values as high as 33,000 U/L have been reported (2). In general, patients diagnosed with rhabdomyolysis appear to have negative myositis-specific autoantibodies and higher CK levels than those without, highlighting the need for close monitoring of CK levels. Rhabdomyolysis associated fatality was reported to be as high as 45% (4 of 9 reported) over a short follow-up duration (1). Our case documents a recovery period in days-weeks with hydration and hemodialysis (3). CONCLUSIONS: Areas for exploration include factors predisposing patients to rhabdomyolysis, utility of checking enzyme levels and impact of vaccination on disease severity. Reference #1: Saud A, Naveen R, Aggarwal R, Gupta L. COVID-19 and Myositis: What We Know So Far. Curr Rheumatol Rep. 2021 Jul 3;23(8):63. doi: 10.1007/s11926-021-01023-9. PMID: 34216297;PMCID: PMC8254439. Reference #2: Husain R, Corcuera-Solano I, Dayan E, Jacobi AH, Huang M. Rhabdomyolysis as a manifestation of a severe case of COVID-19: A case report. Radiol Case Rep. 2020 Jul 7;15(9):1633-1637. doi: 10.1016/j.radcr.2020.07.003. PMID: 32690987;PMCID: PMC7340044. Reference #3: Byler J, Harrison R, Fell LL. Rhabdomyolysis Following Recovery from Severe COVID-19: A Case Report. Am J Case Rep. 2021 May 8;22:e931616. doi: 10.12659/AJCR.931616. PMID: 33963170;PMCID: PMC8127859. DISCLOSURES: No relevant relationships by Asim Amjad No relevant relationships by Sarasija Natarajan No relevant relationships by Pius Ochieng No relevant relationships by Yamini Patel

Case report: post-Covid-19 arthritis and peri arthritis

We present the case of a 63 years old male patient known for type 2 diabetes and sleep apnoea. He was admitted as inpatient for a nontraumatic severe and disabling left hip pain. The pain started progressively one month ago. The medical history was otherwise irrelevant, with no general symptoms nor other symptoms suggestive of an inflammatory disease. To mention a history of an asymptomatic SARS-COV2 infection, diagnosed by a naso-pharyngial PCR, approximately 10 days before the onset of the pain. On physical examination, the patient was afebrile. The palpation of the inguinal region was tender on palpation with marked limitation of the hip range of motion. The spine and other peripheral joints were painless without inflammatory sign. Moreover, there was no skin lesion nor inguinal lymph nods enlargement. Due to the importance of pain with marked functional limitation, the patient is hospitalized for investigations and pain-management. On blood sample there was a mild increase of inflammatory markers (CRP 25mg/l, VS 20mm/h) with normal cell count. Standard X-rays of the pelvis and hip were normal. The MRI of the hip showed a mild coxo-femoral arthritis with marked inflammation of the surrounding musculature. An arthrocentesis was performed and 2ml of serous fluid was aspirated. There were no crystals. The cellularity could not be tested due to small amounts of fluid. The synovial culture showed a polymicrobious growth compatible with contamination. In summary, we were facing a patient with an acute and very painful hip monoarthritis. There was no history of gastrointestinal or urinary tract infection, the search for C. trachomatis and N. gonorrhoea in urines was negative. An extensive serologic testing (HIV, HBV, HCV, HBV, HCV, HIV, Lyme, Syphilis, Coxiella, Bartonella, Brucella & Quantiferon) and the search for T. whipplei were negative as well. There was no HLA-B27 and rheumatoid factor, ACPA, ANA, ANCA and specific antibodies related to polymyositis were negative. The chest-abdomen-pelvis scan showed no sign of neoplasia. To rule out a vasculitis we proceeded to a PET-CT, which showed no sign of vasculitis or myositis. Considering the timing of the onset of the symptoms and the absence of any other diagnosis, the patient was diagnosed with reactive arthritis caused by SARS-COV2. The patient was treated with Diclofenac 150 mg/day and opioids. The clinical evaluation one month after discharge showed a spontaneous significant improvement.

Factors associated with severe COVID-19 in people with idiopathic inflammatory myopathy: results from the COVID-19 Global Rheumatology Alliance physician-reported registry.

OBJECTIVES: To investigate factors associated with severe COVID-19 in people with idiopathic inflammatory myopathy (IIM). METHODS: Demographic data, clinical characteristics and COVID-19 outcome severity of adults with IIM were obtained from the COVID-19 Global Rheumatology Alliance physician-reported registry. A 3-point ordinal COVID-19 severity scale was defined: (1) no hospitalisation, (2) hospitalisation (and no death) and (3) death. ORs were estimated using multivariable ordinal logistic regression. Sensitivity analyses were performed using a 4-point ordinal scale: (1) no hospitalisation, (2) hospitalisation with no oxygen (and no death), (3) hospitalisation with oxygen/ventilation (and no death) and 4) death. RESULTS: Of 348 patients, 48% were not hospitalised, 39% were hospitalised (and did not die) and 13% died. Older age (OR=1.59/decade, 95% CI 1.31 to 1.91), high disease activity (OR=3.50, 95% CI 1.25 to 9.83; vs remission), ≥2 comorbidities (OR=2.63, 95% CI 1.39 to 4.98; vs none), prednisolone-equivalent dose >7.5 mg/day (OR=2.40, 95% CI 1.09 to 5.28; vs no intake) and exposure to rituximab (OR=2.71, 95% CI 1.28 to 5.72; vs conventional synthetic disease-modifying antirheumatic drugs only) were independently associated with severe COVID-19. In addition to these variables, in the sensitivity analyses, male sex (OR range: 1.65-1.83; vs female) was also significantly associated with severe outcomes, while COVID-19 diagnosis after 1 October 2020 (OR range: 0.51-0.59; vs on/before 15 June 2020) was significantly associated with less severe outcomes, but these associations were not significant in the main model (OR=1.57, 95% CI 0.95 to 2.59; and OR=0.61, 95% CI 0.37 to 1.00; respectively). CONCLUSIONS: This is the first large registry data on outcomes of COVID-19 in people with IIM. Older age, male sex, higher comorbidity burden, high disease activity, prednisolone-equivalent dose >7.5 mg/day and rituximab exposure were associated with severe COVID-19. These findings will enable risk stratification and inform management decisions for patients with IIM.