The latest, the first international "myositis" treatment guideline is released, collect it now!

*Read only for medical professionals.
It involves multiple aspects of treatment and is really earned! Idiopathic inflammatory myopathies (IIMs) are a group of rare, heterogeneous autoimmune diseases characterized by muscle inflammation and multiple extramuscular manifestations, usually of chronic or subacute onset, mainly including polymyositis (PM), dermatomyositis (DM), inclusion body myositis (IBM) and other subtypes
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The incidence in adults is 19/1 million people-years, and the incidence in children is 4/1 million people-years
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However, there are currently no standardized guidelines for the treatment of IIM
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In order to better solve this problem, the British College of Rheumatology officially released the guidelines for the management of IIM in children, adolescents and adults on March 31 [1], so that clinicians have more basis for their treatment
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 Screenshot of the guideline The guideline covers thirteen major sections of IIM, including the treatment of myositis, the management of skin manifestations, and the medication associated with interstitial pulmonary lesions
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It sounds like a lot of content, but every sentence is dry! Let's take a look~ 1.
How to treat myositis? 1 Active myositis should be treated with high-dose glucocorticoids during induction therapy (1, B, 100%)
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①Adults: Oral prednisolone is recommended, the dose is 0.
5-1mg/kg/day, usually 40-60mg (1, B, 100%)
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②Pediatrics: Oral prednisolone 1-2mg/kg/day or intravenous methylprednisolone 30mg/kg/day, the maximum daily dose of intravenous injection is 1g (1, B, 100%)
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③ Intravenous methylprednisolone should be considered, especially when there is concern about poor gastrointestinal absorption
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Compared with oral glucocorticoids, intravenous methylprednisolone can improve treatment effect and reduce adverse reactions (2, B, 96%)
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 2 The dose of prednisolone should be tapered according to clinical response (1, B, 100%)
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Glucocorticoids are essential for induction and maintenance therapy of myositis remission
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Glucocorticoids should be discontinued when disease activity improves significantly (usually after about 6 weeks of treatment)
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 3 Myositis should be treated with disease-modifying antirheumatic drugs to achieve clinical remission and reduce steroid burden (1, C, 100%)
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① Pediatrics: Early and complete control of muscle weakness and inflammation in adolescent IIM patients should improve outcomes and reduce disease-related complications (1, B, 100%)
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②Pediatrics: In most cases, high-dose glucocorticoids combined with methotrexate should be the first-line treatment options (1, B, 100%)
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③ Pediatrics: Compared with prednisolone and cyclosporine, prednisolone combined with methotrexate is more suitable for the treatment of adolescent IIM because of its fewer side effects (1, B, 100%)
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④ Pediatrics: Mycophenolate mofetil can treat skin and muscle diseases (2, C, 100%)
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⑤ Adults: Methotrexate, azathioprine, tacrolimus, cyclosporine, and mycophenolate mofetil can treat active myositis and maintain long-term disease remission (2, C, 96%)
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4 Intravenous immunoglobulin (IVIG) may be considered for severe and/or refractory myositis (1, B, 100%)
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5IIM management should include a safe and appropriate exercise program led and supervised by a professional physical therapist and/or professional occupational therapist to improve quality of life and function (1, B, 100%)
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6 Rituximab is an option for the treatment of refractory myositis and may be particularly effective in patients with juvenile-onset, positive myositis autoantibodies, or with low disease impairment (2, A, 100%)
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7 Cyclophosphamide is an option for patients with severe and/or refractory IIM (1, B, 100%)
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Compared with oral cyclophosphamide, intravenous infusion reduces the risk of leukopenia, hemorrhagic cystitis, and gonadal toxicity
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8 Adults: Abatacept is an option for refractory adult IIM patients (2, B, 100%)
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2.
How to treat IIM-related skin manifestations? 1 Rituximab can be used to treat glucocorticoid/csDMARD-resistant skin diseases (2, B, 100%)
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2IVIG can be used to treat glucocorticoid/csDMARD-resistant skin diseases (1, B, 100%)
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3 Avoiding the sun and regularly using a high SPF sunscreen reduces the likelihood of developing skin or muscle disease (2, C, 100%)
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4 Pediatrics: Systemic immunosuppressive drugs may be used to treat active skin disease, including reducing nailfold capillary density (2, C, 100%)
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5 Pediatric: In patients with persistent skin disease, early addition of therapy should be considered to help relieve and reduce the development of calcinosis (2, C, 100%)
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How to manage interstitial lung disease (ILD) associated with IIM? 1 Pediatrics: Because pulmonary function abnormalities are common and may be asymptomatic, routine pulmonary function evaluation should be performed, including measurement of diffusing pulmonary carbon monoxide or transfer factor (DLCO or TLCO) in adolescent IIM (1, B, 100%)
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2 Adults: High-risk patients should be screened for ILD (1, B, 100%)
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3 Adults: In the treatment of rapidly progressive ILD (RP-ILD): Induction therapy with high-dose steroids should be considered (2, C, 96%)
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Cyclosporine, tacrolimus, and steroids should be considered in patients with RP-ILD (2, C, 96%)
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Induction therapy with cyclophosphamide or rituximab should be considered early (2, C, 96%)
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4 Adults: Treatment of chronic IIM-related ILD: glucocorticoids alone or in combination with DMARDs (azathioprine, cyclosporine, tacrolimus, mycophenolate mofetil) should be considered (2, C, 100%)
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Rituximab or cyclophosphamide should be considered in refractory patients (2, C, 100%)
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Note: IM-related ILD management should be performed in conjunction with a respiratory physician
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The risk of ILD is increased with anti-synthetase antibody syndrome, positive anti-synthetase-related autoantibodies, positive anti-melanoma differentiation-associated protein 5 (MDA5) antibodies, and overlapping scleroderma
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Screening methods for ILD include plain chest X-ray, pulmonary function tests (including DLCO), and high-resolution chest CT
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There is insufficient evidence to form a recommendation on the pharmacological management of IIM-related ILD in adolescents
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4.
What measures can be taken to reduce the risk of fracture in IIM patients? Adults: Skeletal evaluation should be performed regardless of glucocorticoid therapy and appropriate management (1, B, 100%)
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5.
What are the key prognostic and management factors that should be considered for adolescent IIM? 1 Adolescent IIM should be managed by a pediatrician because it differs from adult IIM in many ways, including more subcutaneous calcification, less disease lesions, no association with cancer, increased risk of vasculitis, and different autoantibodies (1, C, 95 %)
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2 Time to diagnosis is associated with improved disease outcomes, so early referral to specialist care should be warranted (2, C, 100%)
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3 Age-specific factors should be considered when using tools that measure muscle strength, function, and quality of life (1, B, 100%)
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4 Healthcare professionals should look for overlap with other connective tissue disorders because of an increased risk of death (1, C, 89%)
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5 Adolescent patients with IIM should be evaluated for calcinosis (1, C, 100%)
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Factors associated with an increased risk of calcinosis include younger age of onset, especially in infancy, delayed diagnosis or treatment, more severe disease, longer disease duration, and positivity for anti-nuclear matrix protein 2 (NXP-2) antibodies
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Clinical examination and plain X-ray films can be used to identify calcinosis
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 6.
Is autoantibody detection useful for IIM patients? 1 Patients should be tested for myositis autoantibodies (1, B, 100%)
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Myositis-specific antibodies and myositis-associated autoantibodies are relevant for diagnosis, identification of disease phenotype, and treatment
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Autoantibody titers should not be used to monitor disease activity
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 7.
How should IIM patients be screened for cancer? 1 Pediatric: Routine cancer screening is not required for adolescent IIM (1, B, 100%)
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Compared with adult IIM, adolescent IIM is not associated with cancer, with only a few case reports
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Routine cancer screening for adolescent IIMs is not recommended unless underlying cancer is suspected
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2 Adults: Cancer risk should be considered in all patients, especially those with the following risk factors should pay special attention to screening (1, B, 100%): older age at onset, male sex, dysphagia, skin necrosis, resistance to immunosuppression Treatment resistance, rapid disease onset, positive for anti-transcriptional mediator-1γ (anti-TIF1-γ), positive for anti-NXP-2 antibody, negative for known myositis-specific autoantibodies
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 8.
How should IIM treatment be adjusted during pregnancy and lactation? 1 It is recommended to prepare for pregnancy when the disease is well controlled (1, B, 100%)
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2 Pregnancy should be managed with an obstetrician (1, B, 96%)
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3 Postpartum vigilance is required as patients may be at risk for disease flares (1, C, 96%)
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 9.
How to assess and treat IIM-related cardiovascular disease? 1Adults: Patients should be regularly assessed for cardiovascular risk (1, C, 100%)
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 IIM is associated with increased incidence of hypertension, diabetes, dyslipidemia, obesity, and coronary artery disease (adult-specific)
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2 Pediatrics: Assessment and management of cardiovascular risk factors, including hypertension, obesity, or metabolic abnormalities (lipid/insulin resistance) should be considered (2, C, 100%)
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The causes of hypertension in 25%-50% of JDM patients are related to microangiopathy and glucocorticoid therapy
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Changes in cardiovascular risk factors in patients with juvenile dermatomyositis may contribute to an increased risk of early atherosclerosis in later adulthood
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10.
How to screen for cardiac involvement in IIM? 1 Adults: Patients should be screened for cardiac involvement, including serum cardiac injury markers, electrocardiogram, echocardiography, and cardiac MRI (2, B, 100%)
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2 Adults: Cardiac troponin I (not cardiac troponin T) should be the preferred serum marker for screening and monitoring of cardiac involvement (1, B, 100%)
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3 Pediatrics: Electrocardiography and echocardiography should be considered for screening for cardiac involvement in adolescents with IIM (2, C, 100%)
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 11.
How to screen for and manage IIM-related dysphagia? 1 All patients should be routinely assessed for dysphagia (2, C, 92%)
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2 Swallowing assessment should be considered in patients with dysphagia and requires involvement of a speech-language therapist/gastroenterology team (2, C, 100%)
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3 Active disease and dysphagia resistant to other treatments should be considered for IVIG therapy (2, C, 100%)
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Dysphagia is common, is associated with weight loss and aspiration pneumonia, and can affect quality of life and can be life-threatening in severe cases
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Swallowing dysfunction is not always predicted by generalized muscle weakness, and anti-NXP-2 antibody positivity or malignancy also increases the risk
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 Some scholars believe that dysphagia is an indication for IVIG treatment
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IVIG and other immunomodulatory therapies, such as glucocorticoids, csDMARDs (methotrexate, azathioprine, cyclosporine, tacrolimus, mycophenolate mofetil, hydroxychloroquine), cyclophosphamide, and Rituximab improves dysphagia
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 12.
How to assess and treat the quality of life and mental health of IIM patients? 1 Mental health and psychiatric comorbidities should be assessed (1, C, 92%)
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2 Mental health and health-related quality of life (HRQoL) should be regularly assessed using age-appropriate tools (1, B, 100%)
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3 Factors that negatively impact HRQoL (eg, skin involvement, pruritus, adverse steroid effects) should be addressed (1, C, 96%)
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4 Pediatrics: Negative HRQoL factors in children include pain, muscle weakness, and poor sleep and should be treated appropriately (1, C, 95%)
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5 Individuals within the range of disease activity should be encouraged to engage in individually tailored exercise and/or rehabilitation to improve mental health (1, B, 96%)
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6 Due to the impact of poor grip strength on daily life and quality of life, targeted exercise by a professional physical therapist and/or professional occupational therapist should be considered (2, C, 96%)
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13.
How should IIM be administered for certain racial groups? Race is considered when evaluating patients, as clinical presentation, associated autoantibodies, and potential risk factors may vary by race (2, C, 96%)
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 Ethnic minorities appear to be more susceptible to anti-signal recognition particle (anti-SRP) autoantibody-related disease, increased cardiovascular risk, and to juvenile polymyositis/juvenile connective tissue myopathy
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 Summary The limited high-quality evidence for IIM presented in this guideline is mainly based on observational studies, with a relative lack of randomized controlled trials (RCTs) or head-to-head comparisons
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Therefore, to further evaluate promising treatments, controlled trials are crucial
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And this guide does not address the diagnosis, classification of suspected IIM, nor does it include IBM
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Furthermore, the impact of IIM on mental health and quality of life should not be underestimated
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 Reference: [1] Alexander GS, Oldroyd, et al.
British Society for Rheumatology guideline on management of paediatric, adolescent and adult patients with idiopathic inflammatory myopathy [J].
Rheumatology, 2022;00:1–9.