Search Results (7)

Background/Objectives: Dermatomyositis (DM) is a rare idiopathic inflammatory myopathy characterized by muscle weakness and typical cutaneous rash. Dermatomyositis-specific antibodies, such as anti-TIF1γ, anti-SAE, anti-Mi2, anti-MDA5, and anti-NXP2, have been associated with specific clinical phenotypes. Our study aimed to describe the clinical profile of Moroccan patients with DM and clinical associations with myositis-specific antibodies. Methods: We recruited 54 adult patients with DM according to the Bohan and Peter criteria, admitted to the internal medicine and dermatology departments of the University Hospital Center Ibn Rochd of Casablanca from January 2020 to December 2023. Testing for myositis-specific autoantibodies (MSAs) was conducted using an Immunodot assay. Statistical analysis was performed using the Chi-square test. Results: Among our patients, 74% were female. The mean age of the patients at the time of diagnosis was 45.8 years (±12.95 years). The main clinical manifestations were a V-neck sign (70.4%), myalgia (70.4%), Gottron’s papules (68.5%), heliotrope rash (63%), arthritis/arthralgia (48.1%), proximal muscle weakness (68.5%), periungual erythema (46.3%), and dysphagia (59.3%). Of the 54 patients, 37 (68.5%) showed dermatomyositis-specific antibody positivity. The most frequently found autoantibody was anti-Mi2 (22.2%), followed by anti-TIF1γ (14.8%), anti-NXP2 (9.2%), anti-MDA5 (7.4%), and anti-SAE (7.4%). The association between clinical manifestations and MSAs showed that anti-TIF1γ antibodies were associated with the V-neck sign (p < 0.05), and the MSA-negative group was protected from periungual erythema (p < 0.05). No other significant association was found. Conclusions: This study shows the autoantibody profile of Moroccan patients with DM and the associations of MSAs with clinical manifestations. Full article

Background: Interstitial lung disease (ILD) is a common extra-muscular manifestation of idiopathic inflammatory myopathies (IIMs), often associated with a poorer prognosis and increased mortality risk. Methods: This retrospective study aimed to characterize lung involvement and treatment response in an IIM cohort at a Portuguese tertiary center, followed between June 2016 and March 2024. We analyzed data from high-resolution computed tomography (HRCT) scans and pulmonary function tests (PFTs) to assess associations with autoantibody profiles and treatment regimens. Results: A total of 198 patients were included, with 69 (34.8%) exhibiting ILD. Antisynthetase syndrome (ASyS) and dermatomyositis were the most common diagnoses among IIM-ILD patients, with ASyS being significantly more frequent in this group than in non-ILD patients (p < 0.001). Anti-Jo1 and anti-MDA-5 antibodies were more frequent in ILD patients (p < 0.001 and p = 0.021), while anti-Mi2 antibodies were less common (p = 0.002). Non-specific interstitial pneumonia (NSIP) was the most common radiological pattern (69.5%). IIM-ILD patients presented with significantly lower forced vital capacity (FVC) and diffusing capacity of the lung for carbon monoxide (DLCO) compared to non-ILD patients (p < 0.001 for all values). Longitudinal analysis showed improved DLCO (p = 0.022) and stable or improved FVC (p = 0.097), especially with intravenous immunoglobulin (IVIg) and azathioprine (AZA). Combination therapies including IVIg with mycophenolate mofetil (MMF) or rituximab (RTX) also improved DLCO and FVC. Most ILD patients (89.6%) had stable HRCT patterns over time. Conclusions: Our findings highlight the potential for stabilizing or even improving lung function in IIM-ILD with appropriate immunosuppressive therapy, particularly with regimens incorporating IVIg and AZA, and combination therapies. Full article

Background: The usefulness of myositis-specific autoantibodies (MSAs) and myositis-associated autoantibodies (MAAs) for the assessment of idiopathic inflammatory myopathies (IIMs) is acknowledged, but laboratory standardization remains a challenge. We detected MSAs/MAAs by multi-analytic line immunoassay (LIA) and particle-based multi-analyte technology (PMAT) in a multicenter cohort of patients with IIMs. Methods: We tested the sera from 411 patients affected with definite IIM, including 142 polymyositis (PM), 147 dermatomyositis (DM), 19 cancer-associated myositis, and 103 overlap myositis syndrome (OM), and from 269 controls. MSAs/MAAs were determined by 16Ags LIA in all sera, and anti-HMGCR by ELISA in 157/411 IIM sera and 91/269 control sera. The analytical specificity of LIA/HMGCR ELISA was compared with that of PMAT in 89 MSA+ IIM sera. Results: MSAs/MAAs were positive in 307/411 (75%) IIM patients and 65/269 (24%) controls by LIA (Odds Ratio 9.26, 95% CI 6.43–13.13, p < 0.0001). The sensitivity/specificity of individual MSAs/MAAs were: 20%/100% (Jo-1), 3%/99.3% (PL-7), 4%/98.8% (PL-12), 1%/100% (EJ), 0.7%/100% (OJ), 9%/98% (SRP), 5.6%/99.6% (TIF1γ), 4.6%/99.6% (MDA5), 8%/96% (Mi-2), 1.5%/98% (NXP2), 1.7%/100% (SAE1), 4%/92% (Ku), 8.5%/99% (PM/Scl-100), 8%/96% (PM/Scl-75), and 25.5%/79% (Ro52). Anti-HMGCR was found in 8/157 (5%) IIM patients and 0/176 (0%) controls by ELISA (p = 0.007). Concordance between LIA/HMGCR ELISA and PMAT was found in 78/89 (88%) samples. Individual MSAs detected by LIA were associated with IIM subsets: Jo-1 with PM and OM, PL-12 with OM, Mi-2, TIF1γ, and MDA5 with DM, SRP with PM, and PM/Scl-75/100 with OM (p < 0.001 for all). Conclusions: Since MSAs are mostly mutually exclusive, multi-specific antibody profiling seems effective for a targeted clinical-serologic approach to the diagnosis of IIMs. Full article

Objective: Dermatomyositis associated with anti-MDA5 autoantibodies (DM-MDA5+) is a rare autoimmune disease usually characterized by skin involvement, often-severe lung involvement, and general features. Several reports of infections have been described, sometimes early after the introduction of immunosuppressive therapy. We studied the infection risk in a DM-MDA5+ population. Methods: A retrospective cohort study comparing the number and type of infections during the follow-up of 19 patients with DM-MDA5+ and 37 patients with another type of inflammatory myopathy was analyzed. Patients in both groups were matched on initial immunosuppressive therapy. We described and compared significant infectious complications (SIC) in each group. Results: Patients DM-MDA5+ had more SIC: 27 events in the DM-MDA5+ group versus 6 in the controls (HR 7.08, 95% CI 2.50–20.04, p < 0.0001). The number of SIC per patient was higher in DM-MDA5+ (1.4 ± 1.57 vs. 0.16 ± 0.44, p < 0.001). These were mainly lung (n = 13, 48%) and skin infections (n = 6, 22%), more often infections of an undetermined infectious agent (n = 11, 41%) or of bacterial origin (n = 9, 33%). A few cases of opportunistic infections were reported. The median duration of follow-up without SIC event in the DM-MDA5+ cohort was 3.5 months. Conclusion: Patients with DM-MDA5+ have an increased infection risk compared to others inflammatory myopathies irrespective of immunosuppressive therapy exposure. These results highlight the importance of monitoring for infection during patient follow-up. Full article

Polymyositis and dermatomyositis are autoimmune idiopathic systemic inflammatory diseases, characterized by various degrees of muscle inflammation and typical cutaneous lesions—the latter found in dermatomyositis. The underlying pathogenesis is characterized by a high level of uncertainty, and recent studies suggest diseases may have different immunopathological mechanisms. In polymyositis, components of the cellular immune system are involved, whereas in dermatomyositis, the pathogenesis is mainly mediated by the humoral immune response. The interstitial lung disease occurs in one-third of polymyositis and dermatomyositis patients associated with worse outcomes, showing an estimated excess mortality rate of around 40%. Lung involvement may also appear, such as a complication of muscle weakness, mainly represented by aspiration pneumonia or respiratory insufficiency. The clinical picture is characterized, in most cases, by progressive dyspnea and non-productive cough. In some cases, hemoptysis and chest pain are found. Onset can be acute, sub-acute, or chronic. Pulmonary involvement could be assessed by High Resolution Computed Tomography (HRCT), which may identify early manifestations of diseases. Moreover, Computed Tomography (CT) appearances can be highly variable depending on the positivity of myositis-specific autoantibodies. The most common pathological patterns include fibrotic and cellular nonspecific interstitial pneumonia or organizing pneumonia; major findings observed on HRCT images are represented by consolidations, ground-glass opacities, and reticulations. Other findings include honeycombing, subpleural bands, and traction bronchiectasis. In patients having Anti-ARS Abs, HRCT features may develop with consolidations, ground glass opacities (GGOs), and reticular opacities in the peripheral portions; nonspecific interstitial pneumonia or nonspecific interstitial pneumonia mixed with organizing pneumonia have been reported as the most frequently encountered patterns. In patients with anti-MDA5 Abs, mixed or unclassifiable patterns are frequently observed at imaging. HRCT is a sensitive method that allows one not only to identify disease, but also to monitor the effectiveness of treatment and detect disease progression and/or complications; however, radiological findings are not specific. Therefore, aim of this pictorial essay is to describe clinical and radiological features of interstitial lung diseases associated with polymyositis and dermatomyositis, emphasizing the concept that gold standard for diagnosis and classification–should be based on a multidisciplinary approach. Full article

Clinically amyopathic Dermatomyositis (CADM) is a rare subtype of idiopathic inflammatory myositis, associated with no muscular manifestations, which is more frequent in Asian women. Anti-melanoma differentiation-associated gene 5 (MDA5) antibodies are a recently discovered type of specific autoantibodies associated with myositis. The anti-MDA5 DM was initially described in Japan and later it was discovered that the target antigen was a protein implicated in the innate immune response against viruses, that is encoded by the melanoma differentiation-associated gene 5. Anti-MDA5 DM is characteristically associated with distinguished mucocutaneus and systemic manifestations, including skin ulcerations, palmar papules, arthritis, and interstitial-lung disease. Patients with anti-MDA5 positivity have a high risk of developing rapid progressive interstitial-lung disease (RP-ILD), with a poor outcome. As a result, despite high mortality, diagnosis is often delayed, necessitating increased awareness of this possible condition. Despite a severe course of lung disease and an increased mortality rate, there is currently no standard treatment. Recent insights based on observational studies and case reports support combined therapy with immunosuppressive drugs and corticotherapy, as soon as the symptoms appear. The aim of this paper is to describe anti-MDA5 DM, focusing on the recent literature about the unique clinical manifestations and therapeutic options, starting from a severe clinical case diagnosed in our Rheumatology Department. Full article

Idiopathic inflammatory myopathies, including polymyositis (PM), dermatomyositis (DM), and clinically amyopathic DM (CADM), are a diverse group of autoimmune diseases characterized by muscular involvement and extramuscular manifestations. Interstitial lung disease (ILD) has major pulmonary involvement and is associated with increased mortality in PM/DM/CADM. The management of PM-/DM-/CADM-associated ILD (PM/DM/CADM-ILD) requires careful evaluation of the disease severity and clinical subtype, including the ILD forms (acute/subacute or chronic), because of the substantial heterogeneity of their clinical courses. Recent studies have highlighted the importance of myositis-specific autoantibodies’ status, especially anti-melanoma differentiation-associated gene 5 (MDA5) and anti-aminoacyl tRNA synthetase (ARS) antibodies, in order to evaluate the clinical phenotypes and treatment of choice for PM/DM/CADM-ILD. Because the presence of the anti-MDA5 antibody is a strong predictor of a worse prognosis, combination treatment with glucocorticoids (GCs) and calcineurin inhibitors (CNIs; tacrolimus (TAC) or cyclosporin A (CsA)) is recommended for patients with anti-MDA5 antibody-positive DM/CADM-ILD. Rapidly progressive DM/CADM-ILD with the anti-MDA5 antibody is the most intractable condition, which requires immediate combined immunosuppressive therapy with GCs, CNIs, and intravenous cyclophosphamide. Additional salvage therapies (rituximab, tofacitinib, and plasma exchange) should be considered for patients with refractory ILD. Patients with anti-ARS antibody-positive ILD respond better to GC treatment, but with frequent recurrence; thus, GCs plus immunosuppressants (TAC, CsA, azathioprine, and mycophenolate mofetil) are often needed in order to achieve favorable long-term disease control. PM/DM/CADM-ILD management is still a therapeutic challenge for clinicians, as evidence-based guidelines do not exist to help with management decisions. A few prospective clinical trials have been recently reported regarding the treatment of PM/DM/CADM-ILD. Here, the current knowledge on the pharmacologic managements of PM/DM/CADM-ILD was mainly reviewed. Full article