Dynamic change in red cell distribution width as a predictor for short-time mortality in dermatomyositis-associated rapid progressive interstitial lung disease.

AIM: We aimed to explore a new and readily available practical marker for rapidly progressive interstitial lung disease (RP-ILD) and poor short-term outcomes in patients with idiopathic inflammatory myopathies (IIM). METHODS: A total of 1822 consecutive patients with IIM between 2009 and 2021 were evaluated retrospectively. All proven cases of naïve ILD with complete medical records were included. Red cell distribution width (RDW) values at the initial stage, 3 months and last follow-up were collected. The clinical characteristics and outcomes of the patients were recorded. RESULTS: We identified 532 patients with IIM with an average follow-up of 4 years. ILD prevalence was higher in patients of elevated RDW (p<0.001). The patients with ILD and elevated RDW had lower levels of PaO2/FiO2, FVC% and DLco% and a higher prevalence of RP-ILD than those with normal RDW (p<0.001). Prognostic analysis revealed that RDW was an independent risk factor for prognosis in patients with IIM-ILD (HR=2.9, p=0.03). Patients with dermatomyositis (DM) with RP-ILD with a change in RDW within 3 months (∆RDW-3) greater than 0 were more likely to die within 3 months. Moreover, the prevalence of ∆RDW-3>0 was higher in patients with RP-ILD and positive for anti-melanoma differentiation-associated gene 5 antibody who died within 3 months (87.5%) compared with those alive at 3 months (24.6%) (p<0.001). CONCLUSION: These findings suggest that repeated RDW assays could assist physicians in identifying patients with DM-ILD who were at a high risk of RP-ILD and death.

Cancer Risk and Mortality in Hospitalized Patients With Idiopathic Inflammatory Myopathies in Western Australia.

OBJECTIVE: To compare cancer incidence, type, and survival between patients with idiopathic inflammatory myopathies (IIMs) in Western Australia (WA) and the general population. METHODS: Administrative health data for hospitalized patients with incident IIM (n = 803, 56.5% female, median age 62.0 yrs), classified by a validated algorithm as polymyositis (PM; 36.2%), dermatomyositis (DM; 27.4%), inclusion body myositis (IBM; 17.1%), overlap myositis (OM; 10.7%), and other IIM (8.6%), were linked to WA cancer and death registries for the period of 1980 to 2014. Cancer incidence rates (CIRs) before and after IIM diagnosis as well as cancer mortality were compared with age-, sex-, and calendar year-matched controls (n = 3225, 54.9% female, median age 64 yrs) by rate ratios (RRs) and Kaplan-Meier survival estimates. RESULTS: The prediagnosis CIR was similar for patients with IIM and controls (6.57 vs 5.95; RR 1.11, 95% CI 0.88-1.39) and for patients evolving to DM (n = 220) or other IIM subtypes (6.59 vs 6.56; RR 1.01, 95% CI 0.38-3.69). During follow-up, CIR was higher for all DM (4.05, 95% CI 3.04-5.29), with increased CIR for lung cancer vs controls (1.05 vs 0.33; RR 3.18, 95% CI 1.71-5.47). Cancer post diagnosis shortened life span by 59 months for patients with IIM (103 vs 162 months, P < 0.01), but reduced survival rates were observed only in patients with DM and IBM. CONCLUSION: Cancer risk was not increased prior to IIM, but CIR for lung cancer was increased following DM diagnosis. As cancer reduced survival only in patients with DM and IBM, these data support a strategy of limited cancer screening in IIM.

Calcinosis in Juvenile Dermatomyositis-Epidemiology, Pathogenesis, Clinical Features, and Treatment: A Systematic Review.

PURPOSE OF REVIEW: We performed a systematic review of the literature on the epidemiology, pathogenesis, clinical and laboratory characterization, and treatment of calcinosis in patients with juvenile dermatomyositis (JDM). A qualitative systematic review was conducted from January 1975 to April 2023 according to the PRISMA protocol using three electronic databases: PubMed, Web of Science, and Scopus. Studies were analyzed based on the following eligibility criteria: at least one combination of the terms described in the search strategy appeared in the title, written in English, Portuguese, or Spanish, and addressed the epidemiology, pathogenesis, diagnosis, and treatment of calcinosis in juvenile dermatomyositis. Systematic or scoping reviews, letters, clinical images, book chapters, abstracts, inflammatory myopathy in other connective tissue diseases, idiopathic inflammatory myopathies in adults, and purely qualitative studies were excluded. RECENT FINDINGS: Seventy-five studies were included. According to the literature, calcinosis is common in women, around five years old, with three years of disease in association with osteoarticular, cutaneous, pulmonary manifestations, and fever. The pathogenesis is still unknown, but the participation of interleukin 1 and 6, tumor necrosis factor alpha, and innate immunity dysregulation seem to be involved. Common autoantibodies are anti-NXP-2, anti-MDA-5, and anti-Mi-2, and their treatment remains controversial. Prospective, randomized, controlled studies are needed to evaluate treatment protocols and map the natural history of this serious complication. Calcinosis seems to be more common in White female children with muscle weakness, fever, arthritis, severe pulmonary, and skin involvement with anti-NXP-2, anti-MDA-5, and anti-Mi-2 autoantibodies. The multitargets and aggressive treatment is recommended.

Gender differences in patients with anti-MDA5-positive dermatomyositis: a cohort study of 251 cases.

OBJECTIVE: To investigate the impact of sex differences on the clinical characteristics and prognosis of patients with anti-melanoma differentiation-associated gene 5-positive dermatomyositis (MDA5+ DM). METHODS: We retrospectively analyzed a cohort of 251 patients with MDA5+ DM, including 71 in the male group and 180 in the female group. A multivariate logistic regression model was built to analyze independent risk factors for RPILD in each group. An ROC curve was drawn to evaluate the predictive value of independent risk factors. Kaplan‒Meier analysis was used to compare the cumulative survival rates, while the log-rank test was used to test for significant differences between the two groups. RESULTS: Patients in the male group had a significantly higher prevalence of heliotrope rash, V sign, severe interstitial lung disease (ILD), and rapidly progressive interstitial lung disease (RPILD) than those in the female group. Anti-Ro52 positivity, high CRP level and short disease were identified as independent risk factors for RPILD in both male and female groups by multivariate logistic regression analysis. The mortality rates of males and females were 33.8% and 22.0%, respectively, and the survival time of patients in the male group was shorter than that in the female group. CONCLUSION: Male patients with MDA5+ DM exhibit an increased risk of RPILD, elevated mortality rates and reduced overall survival time compared to their female counterparts, and anti-Ro52 positivity may be an unfavorable prognostic factor for these patients. Key Points • The prevalence of solar rash, V sign, severe interstitial lung disease (ILD) and rapidly progressive interstitial lung disease (RPILD) in anti-MDA5-positive female patients was significantly lower than that in male patients. • Positive Anti-Ro52, high CRP level, and short course of disease were independent risk factors for RPILD in both men and women. • Female patients exhibited a lower mortality rate than male patients (22.0% vs 33.8%) and demonstrated longer survival time.

Obesity is an independent risk factor for cancer development following diagnosis of dermatomyositis.

Patients with dermatomyositis (DM) are at an increased risk of cancer development, especially around the time of diagnosis of DM. Obesity is also a risk factor in the general population for cancer development. This study aimed to assess the association between cancer in DM patients with and without obesity as defined by ICD code and BMI data. In this analysis of patients with DM, logistic regression modeling of the odds of cancer outcome was performed for patients with DM and obesity compared to those without obesity, adjusted for age and sex. A total of 12,722 patients with DM were identified, of whom 6,055 had available BMI data. DM patients who were coded obese at any point had significantly higher odds 1.98 (95 % Confidence interval (CI) 1.70, 2.30) of a subsequent cancer diagnosis. This association was also found in the subgroup analysis with available BMI where patients with obesity (BMI ≥30 kg/m2) had an increased odds of cancer 1.23 (1.02, 1.49) when compared to patients with BMI <30 kg/m2 with DM. In time to event analysis any obesity code was associated with a 16 % increased hazard of cancer (adjusted hazard ratio 1.16 [95 % CI 1.02, 1.31]). Overall, the most frequent type of cancer was breast cancer, however patients with DM and obesity had higher frequencies of lymphoma, colorectal, melanoma, uterine, renal cancers compared to patients with DM without obesity.

Clinical and laboratory characteristics of idiopathic inflammatory myositis in Saudi patients: A retrospective study in a single tertiary centre.

OBJECTIVES: Idiopathic inflammatory myositis (IIM) in Saudi patients has been poorly studied owing to the lack of available data. This study aimed to identify the clinical and laboratory features of patients at a single tertiary care center. METHODS: This retrospective study reviewed the medical records of Prince Sultan Military Medical City, Riyadh, Saudi Arabia to collect clinical and laboratory data between December 2022 and February 2017 as follows: age at disease onset, gender, follow-up duration and disease duration; clinical symptoms; laboratory result; presence and type of myositis-specific autoantibody or myositis-associated autoantibody; and type of immunosuppression, presence of malignancy, disease course, and outcome. RESULTS: There were 26 patients with a mean age of 36.16±13.48, and 84.6% were women. The most prevalent form of IIM was dermatomyositis (n=16, 61.5%), and the most affected organ was the skin. weakness was observed in 25 patients (96.2%), and dysphagia was the most common alarm sign (n=10, 38.5%). During follow-up, the creatine kinase level was elevated at the beginning of the disease and then decreased following treatment, with a mean of 277.73 IU/L. Of the total patients, 17 (68%) were positive for anti-nuclear antibody and 5 (19.2%) were positive for anti-Jo-1. CONCLUSION: In our patients, dermatomyositis was the most common form of myositis, and skin manifestations were the most prevalent clinical characteristics. None of the patients developed a malignancy or died.

Age distribution and prevalence in different age groups of four myositis-specific autoantibodies, including anti-ARS, anti-MDA5, anti-Mi-2, and anti-TIF1γ antibodies.

We accumulated the demographic information and analyzed the prevalence of myositis-specific antibodies (MSAs) in a large cohort across Japan as standard testing for MSAs becomes more widely available. This retrospective, observational, cohort study analyzed the records of individuals aged 0-99 years who are tested for serum MSAs at SRL Incorporation from January 2014 to April 2020 across Japan. An enzyme-linked immunosorbent assay testing was applied to determine the presence of anti-aminoacyl tRNA synthetase (anti-ARS), anti-Mi-2, anti-melanoma differentiation-associated gene 5 (anti-MDA5), or anti-transcriptional intermediary factor 1-γ (anti-TIF1γ) (Medical and Biological Laboratories). Anti-TIF1γ antibody was detected more in male patients than female patients. In contrast, women were predominant in patients with other MSAs. More than half of the anti-ARS or anti-TIF1γ antibody-positive patients were over 60 years old, although anti-MDA5 or anti-Mi-2-positive patients were mostly under <60 years old. Anti-MDA5 antibody-positive patients were mostly aged 40-59 years, while other MSA groups were mostly 60-79 years. Anti-MDA5 antibody was detected most frequently in the age range of 0-29 years. Anti-TIF1γ antibody was the second most commonly detected autoantibody in the age range of 0-19 years. Anti-ARS antibody was the most frequently detected autoantibody after the age of 30 years, and the frequency of anti-ARS gradually increased at more advanced ages. The second and third most detected autoantibodies were anti-MDA5 and anti-TIF1γ, respectively, in ages 30-79 years. We performed a nationwide >3-year evaluation of MSA detection in a routine diagnostic setting. This paper provides clinical images concerning the relationship between four MSA types and the distribution of sex and age in a large population.

High prevalence and mortality of Pneumocystis jirovecii pneumonia in anti-MDA5 antibody-positive dermatomyositis.

OBJECTIVES: To identify potential risk factors and prognostic factors of Pneumocystis jirovecii pneumonia (PJP) infection in anti-melanoma differentiation-associated gene 5 antibody-positive DM (anti-MDA5+ DM) patients, and to evaluate the diagnostic performance of metagenomic next-generation sequencing (mNGS). METHODS: Anti-MDA5+ DM patients who underwent mNGS or real-time PCR for PJP detection were recruited. The potential risk factors for PJP occurrence and death were analysed via Logistic regression and Cox proportional hazards regression, respectively. The diagnostic efficacy of mNGS was compared with the conventional methods. RESULTS: 91 patients were enrolled and 44 were assigned to PJP+ group. The PJP detection rate was 48.4%. PJP often occurred in the first 3 months (68.2%) of the disease; this period also showed the highest mortality rate (20.5%). Fever and increased lactate dehydrogenase (LDH) were independent risk factors for PJP occurrence, while trimethoprim-sulfamethoxazole (TMP/SMZ) prophylaxis was an independent protective factor (all P < 0.05). Older age and increased LDH were predictors for mortality in patients with anti-MDA5+ DM and PJP (all P < 0.05). In addition, we found that mNGS had a sensitivity of 100.0% and specificity of 90.0% in diagnosing PJP, with the highest area under the curve of 0.95 (P < 0.001). CONCLUSION: PJP has high prevalence and mortality in anti-MDA5+ DM. It is crucial for clinicians to identify high-risk patients and promptly institute TMP/SMZ to prevent PJP. mNGS is the preferred approach for pathogen detection in anti-MDA5+ DM when PJP is suspected.

Subsets of Idiopathic Inflammatory Myositis Enriched for Contemporaneous Cancer Relative to the General Population.

OBJECTIVE: This study investigates cancer risk in idiopathic inflammatory myopathy (IIM) relative to the general population. METHODS: We conducted a single-center, retrospective cohort study of IIM patients and malignancy. Myositis-specific and -associated autoantibodies were determined by Euroimmun line blot, enzyme-linked immunosorbent assay, and immunoprecipitation. We calculated standardized prevalence ratios (SPRs) and adjusted for calendar year, age, sex, race, and ethnicity by comparing observed cancers in IIM patients versus expected cancers in the general population using the Surveillance, Epidemiology, and End Results registry. RESULTS: Of 1,172 IIM patients, 203 (17%) patients with a cancer history were studied. Over a median follow-up of 5.2 years, the observed number of IIM patients diagnosed with cancer was increased 1.43-fold (SPR 1.43 [95% confidence interval (95% CI) 1.15-1.77]; P = 0.002). Within 3 years of IIM symptom onset, an increased SPR was observed for anti-transcription intermediary factor 1γ (anti-TIF1γ)-positive patients for ovarian and breast cancer (ovarian SPR 18.39 [95% CI 5.01-47.08], P < 0.001; breast SPR 3.84 [95% CI 1.99-6.71], P < 0.001). As expected, anti-TIF1γ positivity was associated with a significantly elevated SPR; however, only 55% (36 of 66) of all cancers within 3 years of dermatomyositis onset were observed in anti-TIF1γ-positive patients. Other myositis-specific autoantibodies, including anti-Mi-2, anti-small ubiquitin-like modifier activating enzyme (SAE), and anti-nuclear matrix protein 2 (NXP-2), accounted for 26% (17 of 66) of cancers diagnosed within 3 years of dermatomyositis onset. No cancer association, positive or negative, was observed for patients with antisynthetase, anti-melanoma differentiation-associated protein 5 (anti-MDA-5), or anti-hydroxymethylglutaryl-coenzyme A reductase (anti-HMGCR) antibodies. CONCLUSION: In a tertiary referral center population, anti-TIF1γ was most strongly associated with breast and ovarian cancer. Patients with antisynthetase, anti-MDA-5, or anti-HMGCR antibodies had the same cancer risk as the general population.

COVID-19 outcomes in patients with Dermatomyositis: A registry-based cohort analysis.

BACKGROUND: Patients with rheumatic diseases (RDs) like DM are known to be vulnerable towards various types of infections due to aggressive disease activity mandating high dose immunosuppressive therapy. The severity of COVID-19 in RDs is limited in literature due to the heterogeneous nature of the condition. Therefore, specific details on mortality is essential to navigate any precautions required in the treatment. OBJECTIVES: To determine outcomes of COVID-19 in DM as compared to controls, and identify the risk association of gender, race, interstitial lung disease, neoplasms, and use of immunosuppressant. METHODS: Retrospective data of individuals with DM and COVID-19 and the general population with COVID-19 between January 2020 to August 2021 was retrieved from the TriNetX database. 1:1 Propensity Score matching was used to adjust for confounders. We assessed COVID-19 outcomes such as mortality, hospitalisation, ICU admission, severe COVID-19, mechanical ventilation (MV), acute kidney injury (AKI), venous thromboembolism (VTE), ischemic stroke, acute respiratory distress syndrome (ARDS), renal replacement therapy (RRT) and sepsis. Subgroup analyses included gender, race, ILD, cancer patients, disease-modifying rheumatic drugs (DMARDs) use, and glucocorticoids (GC) use. RESULTS: We identified 5,574 DM patients with COVID-19, and 5,574 general population with COVID-19 (controls). DM with COVID-19 had a lower risk of mortality in comparison to controls [RR 0.76], hospitalisation [RR 0.8], severe COVID-19 [RR 0.76], AKI [RR 0.83], and sepsis [RR 0.73]. Males and African Americans were more likely to develop AKI [RR 1.35, 1.65], while African Americans had higher odds for severe COVID-19 [RR 1.62] and VTE [RR 1.54]. DM with ILD group also experienced higher odds for severe COVID-19 infection [RR 1.64], and VTE [RR 2.06]. DM patients receiving DMARDs and glucocorticoids had higher odds for hospitalisation [RR 1.46, 2.12], and sepsis [RR 3.25, 2.4] Subgroup analysis of 5-year neoplasm history amongst DM patients with COVID-19 was inadequate for meaningful comparison. CONCLUSION: Dermatomyositis patients without comorbities have reasonable COVID-19 outcomes including mortality and hospitalisation. Black race, male gender, ILD, DMARDS and glucocorticoid users, are associated with poor outcomes.

Autoantibodies and Cancer Association: the Case of Systemic Sclerosis and Dermatomyositis.

Several rheumatic diseases have a perplexing association with cancer. Unraveling this mysterious connection is likely to provide deeper understanding regarding mechanisms governing the onset of both autoimmunity and cancer immunity, in addition to providing clinicians much needed guidance around whom and when to screen for occult malignancy. Systemic sclerosis (scleroderma) and dermatomyositis are two diseases in which the association with internal malignancy is well-described and can be considered as models from which to gain important insights that likely have broader applicability. The past 15 years have witnessed a striking acceleration in understanding how these two diseases are related to cancer emergence-an important crack in this inscrutable armor has been the discovery and characterization of disease-specific autoantigens that are closely tied with risk of cancer emergence. The best-described examples of this are antibodies against anti-RNA polymerase III (anti-POL3) and transcription intermediary factor 1-gamma (anti-TIF1γ). Patients with systemic sclerosis and cancer that are diagnosed within a short time interval of each other frequently have anti-POL3 antibodies. Antibodies against the minor spliceosome protein RNA-Binding Region Containing 3 (RNPC3) are also associated with increased cancer incidence in systemic sclerosis. Similarly, in the dermatomyositis spectrum, the majority of anti-TIF1γ-associated cancers are detected around the time of DM onset (most often within 1 year). Antibodies against Nuclear Matrix Protein 2 are also potentially associated with increased cancer emergence in dermatomyositis. The systemic sclerosis/anti-POL3 connection with close cancer onset led to the first experiments directly supporting the concept that rheumatic disease may in fact be a manifestation of cancer. It is now clear that studying these diseases through the lens of autoantibodies can reveal relationships and insights that would otherwise remain obscured. Extending these studies, new findings show that antibodies against RNA polymerase I large subunit are associated with protection against short interval cancers in anti-POL3-positive systemic sclerosis patients. These insights highlight the fact that autoantigen discovery related to cancer emergence remains an important priority; such new tools will enable the testing of specific hypotheses regarding mechanisms governing disease emergence and development of effective anti-tumor responses. Autoantibody phenotype will likely play an important role in the development of cancer screening guidelines that are critically needed by clinicians taking care of these patients. In this review, we will summarize the current state of knowledge regarding the different ways in which autoantibodies are connected with systemic sclerosis/dermatomyositis and malignancy and highlight potential paths forward.

Clinical and histopathological features of myositis in systemic lupus erythematosus.

OBJECTIVE: The objectives of this study were to compare the clinical features of patients with SLE with and without myopathy and to describe the muscle biopsy features of patients with SLE myopathy. METHODS: This nested case-control study included all subjects enrolled in the Hopkins Lupus Cohort database from May 1987 to June 2016. Subjects with elevated creatine kinase along with evidence of muscle oedema on MRI, myopathic electromyography and/or myopathic muscle biopsy features were defined as having SLE myopathy. Demographic, serological and clinical features were compared between patients with SLE with and without myopathy. Muscle biopsies were histologically classified as polymyositis, dermatomyositis, necrotising myopathy or non-specific myositis. RESULTS: From among 2437 patients with SLE, 179 (7.3%) had myopathy. African American patients were more likely to develop myositis than Caucasian patients (p<0.0001). Compared with those without myopathy, patients with SLE myopathy were more likely to have malar rash (OR 1.67, 1.22-2.29), photosensitivity (OR 1.43, 1.04-1.96), arthritis (OR 1.81, 1.21-2.69), pleurisy (OR 1.77, 1.3-2.42), pericarditis (OR 1.49, 1.06-2.08), acute confusional state (OR 2.07, 1.09-3.94), lymphopaenia (OR 1.64, 1.2-2.24), anti-double-stranded DNA antibodies (OR 1.52, 1.09-2.13), lupus anticoagulant (OR 1.42, 1-2), cognitive impairment (OR 1.87, 1.12-3.13), cataract (OR 1.5, 1.04-2.18), pulmonary hypertension (OR 1.98, 1.13-3.47), pleural fibrosis (OR 2.01, 1.27-3.18), premature gonadal failure (OR 1.9, 1.05-3.43), diabetes (OR 1.92, 1.22-3.02) or hypertension (OR 1.45, 1.06-2). Among 16 muscle biopsies available for review, the most common histological classifications were necrotising myositis (50%) and dermatomyositis (38%). CONCLUSIONS: Patients with SLE myopathy have a higher prevalence of numerous SLE disease manifestations. Necrotising myopathy and dermatomyositis are the most prevalent histopathological features in SLE myopathy.

Immune responses to CCAR1 and other dermatomyositis autoantigens are associated with attenuated cancer emergence.

BACKGROUNDThe temporal clustering of a cancer diagnosis with dermatomyositis (DM) onset is strikingly associated with autoantibodies against transcriptional intermediary factor 1-γ (TIF1-γ). Nevertheless, many patients with anti-TIF1-γ antibodies never develop cancer. We investigated whether additional autoantibodies are found in anti-TIF1-γ-positive patients without cancer.METHODSUsing a proteomic approach, we defined 10 previously undescribed autoantibody specificities in 5 index anti-TIF1-γ-positive DM patients without cancer. These were subsequently examined in discovery (n = 110) and validation (n = 142) cohorts of DM patients with anti-TIF1-γ autoantibodies.RESULTSWe identified 10 potentially novel autoantibodies in anti-TIF1-γ-positive DM patients, 6 with frequencies ranging from 3% to 32% in 2 independent DM cohorts. Autoantibodies recognizing cell division cycle and apoptosis regulator protein 1 (CCAR1) were the most frequent, and were significantly negatively associated with contemporaneous cancer (discovery cohort OR 0.27 [95% CI 0.7-1.00], P = 0.050; validation cohort OR 0.13 [95% CI 0.03-0.59], P = 0.008). When cancer did emerge, it occurred significantly later in anti-CCAR1-positive compared with anti-CCAR1-negative patients (median time from DM onset 4.3 vs. 0.85 years, respectively; P = 0.006). Cancers that emerged were more likely to be localized (89% of anti-CCAR1-positive cancers presenting at stage 0 or 1 compared with 42% of patients without anti-CCAR1 antibodies, P = 0.02). As the number of additional autoantibody specificities increased in anti-TIF1-γ-positive DM patients, the frequency of cancer decreased (P < 0.001).CONCLUSIONAs the diversity of immune responses in anti-TIF1-γ DM patients increases, the likelihood of cancer emerging decreases. Our findings have important relevance for cancer risk stratification in DM patients and for understanding natural immune regulation of cancer in humans.TRIAL REGISTRATIONNot applicable.FUNDING SOURCESThe NIH, the Donald B. and Dorothy L. Stabler Foundation, and the Huayi and Siuling Zhang Discovery Fund.

Infection is not rare in patients with idiopathic inflammatory myopathies.

OBJECTIVES: To assess the prevalence and characteristics of infections in patients with idiopathic inflammatory myopathies (IIM) and analyse risk factors for infection using clinical presentation and biochemical findings of IIM. METHODS: Retrospective review of the medical records of patients with IIM followed up in a single medical centre from January 2008 to January 2018. RESULTS: Of the 779 patients with IIM, 215 (27.6%) suffered from infections. The prevalence of infection in dermatomyositis (DM) (29.8%) was more than polymyositis (PM) (18.5%). The lung was the most common infection site (66.5%). Multivariate analyses demonstrated that methylprednisolone pulse (MP) (OR=3.22; 95% CI=1.60 - 6.48; p=0.001), age of onset >50 years (OR=1.02; 95% CI=1.00 - 1.03; p=0.011), anti-melanoma differentiation-associated gene 5 (MDA5) antibody (OR=1.93; 95% CI=1.20 - 3.11; p=0.007), lymphocyte count <1200/mm3 (OR=2.85; 95% CI=1.89 - 4.30; p<0.001), and interstitial lung diseases (ILD) (OR=2.03; 95% CI=1.30 - 3.71; p=0.002) are independent risk factors for infection. Survival analysis demonstrated that the three-year survival rate in the infection group was lower than the no-infection group (75.3% vs. 94.7%, p < 0.001). CONCLUSIONS: Among hospitalised individuals with IIM, infection is frequent and the leading cause of mortality. The anti-MDA5 antibody, lymphopenia, ILD, old age, and treatment with MP are contributing factors in the development of infections in patients with IIM.

A juvenile dermatomyositis: demographics, characteristics and disease outcome in an Egyptian cohort.

OBJECTIVES: To study the demographics, characteristics, management and disease outcome of Egyptian children with juvenile dermatomyositis (JDM). METHODS: Retrospective analysis of the records of 134 JDM patients attending two centres in Cairo, Egypt from January 2010 to December 2019. A total of 128 patients were included in the study, all of which fulfilled either the Bohan and Peter criteria and/or the EULAR/ACR classification criteria of 2017. RESULTS: The mean age of disease onset was 5.9±2.8 years and the follow-up duration were 6±3.2 years. Female to male ratio was 2.2:1. Constitutional manifestations and cutaneous skin ulcers were common, while gut vasculopathy was rare in our patients. Heliotrope rash was the commonest skin manifestation. Lactate dehydrogenase enzyme was more frequently elevated than creatine kinase. Electromyography was the most frequently used diagnostic procedure, while muscle biopsy and muscle MRI were not commonly done in our patients. Glucocorticoids, methotrexate, hydroxychloroquine, mycophenolate mofetil and IVIG were the most frequently used medications. Sixty (46.9 %) of the patients had clinically inactive disease, at the last follow-up visit. Chronic skin disease, residual muscle weakness, calcinosis and growth failure were among the most common cumulative damage manifestations. The mortality rate was 1.6% over the follow-up period, one death was due to severe infection, and the other due to respiratory failure. CONCLUSIONS: Although our patients shared several similarities with their peers in the Middle East and in Europe, there were some striking differences. These differences can be attributed to the ethnic and environmental disparities.

A retrospective cohort study in Chinese patients with adult polymyositis and dermatomyositis: risk of comorbidities and subclassification using machine learning.

OBJECTIVES: To identify the risk factors in Chinese patients with adult polymyositis and dermatomyositis for their comorbidities and explore a subclassification system. METHODS: Clinical records of 397 patients with idiopathic inflammatory myopathies were retrospectively reviewed. Logistic regression was used to identify potential risk factors for interstitial lung disease (ILD), other rheumatic diseases, and malignancy after bivariate analysis. Hierarchical clustering and decisional tree were utilised to identify subgroups and explore a subclassification system. RESULTS: A total of 119 polymyositis and 191 dermatomyositis patients were included. Anti-PM/Scl, anti-Ro52, anti-aminoacyl-tRNA synthetase and anti-MDA5 (adjusted odds ratios (AOR)=4.779, 1.917, 5.092 and 7.714 respectively) antibodies were risks (p<0.05), whereas overlapping malignancy was protective (AOR=0.107; p=0.002) for ILD across polymyositis, dermatomyositis and the total group. In subgroup models, Raynaud's phenomenon, arthralgia and semi-quantitative anti-nuclear antibody (AOR=51.233, 4.261, 3.047 respectively) were risks for other overlapping rheumatic diseases (p<0.05). For overlapping malignancy, male and anti-TIF1γ antibodies (AOR=2.533, 16.949) were risks (p<0.05), whereas disease duration and combination of ILD (AOR=0.954, 0.106) were protective in the total group (p<0.05); while anti-NXP2 antibodies were identified as risk factors (AOR=73.152; p=0.038) in polymyositis. Hierarchical clustering suggested a subclassification with 6 subgroups: malignancy overlapping dermatomyositis, classical dermatomyositis, polymyositis with severe muscle involvement, dermatomyositis with ILD, polymyositis with ILD, and overlapping of myositis with other rheumatic diseases. CONCLUSIONS: Accompanying ILD, other rheumatic diseases and malignancy are strongly associated with clinical manifestation and myositis-specific or myositis-associated autoantibodies among Chinese polymyositis and dermatomyositis patients. The subclassification system proposed a more precise phenotype defining toward stratified treatments.

Characterization of Patients With Dermatomyositis According to Anti-Melanoma Differentiation-Associated Gene-5 Autoantibodies in Centers from 3 Latin American Countries: A Cohort Study.

BACKGROUND/OBJECTIVE: The anti-melanoma differentiation-associated protein 5 (MDA5) autoantibodies have been associated with a high frequency of interstitial lung disease (ILD) and rapidly progressive ILD (RP-ILD) in dermatomyositis (DM) patients, mainly in Asian subjects. However, there is scarce information about these parameters in Latin American patients. METHOD: This was a medical records review cohort study that included classic DM (CDM) and clinically amyopathic DM (CADM) patients from 3 Latin American countries (Argentina, Brazil, and Mexico). RESULTS: A total of 270 DM patients were evaluated: 25.9% with CADM and 74.1% with CDM. The overall prevalence of ILD and RP-ILD, respectively, was 70 (25.9%) and 4 (1.5%) of the 270 patients, and the distributions were comparable between patients with CDM and CADM. The anti-MDA5 was present in 31 (25.4%) of 122 CDM patients and in 17 (48.6%) of 35 CADM patients; it was not associated with presence of ILD and RP-ILD. However, anti-MDA5-positive CDM patients had significantly high frequency of "mechanic's hands," arthralgia, arthritis, and lower serum levels of creatine phosphokinase, whereas anti-MDA5-positive CADM patients had significantly high frequency of arthritis. Pulmonary infection and ILD are main causes of death in DM patients. CONCLUSIONS: In the present study, the prevalence of ILD in DM patients is comparable to that described in the literature, in contrast to the very low frequency of RP-ILD. In addition, the anti-MDA5 is not associated with ILD and RP-ILD, but anti-MDA5-positive DM patients present conditions that mimic antisynthetase syndrome. Pulmonary infection and ILD were the main causes of death in our sample.

Clinical heterogeneities and prognoses of patients with myositis specific antibody negative dermatomyositis: a retrospective study in China.

OBJECTIVES: The clinical features of myositis specific antibody negative dermatomyositis (MSA negative DM) varied greatly, and there were few reports in the literatures. This study aimed to describe and expand the clinical phenotypes and prognoses of MSA negative DM patients. METHODS: MSA negative DM patients were identified from January 2010 to June 2020. We retrospectively reviewed the clinical features and laboratory data. The survival status was followed up until July 31. 2020 SPSS version 21.0 and R version 3.6.1 software were used for the statistical analyses. RESULTS: A total of 97 MSA negative DM patients were enrolled. The most common type of rashes was heliotrope rash (80.4%). More than half of the patients (55.7%) had interstitial lung disease (ILD), and seven of them developed rapid progressive ILD. There were eleven patients with tumours. During the follow-up, twelve patients died, of whom 5 (41.7%) died due to infection. Two phenotypes of MSA negative DM patients were identified by cluster analysis. Patients in cluster 1 developed muscle weakness, mechanic's hands, arthritis, and ILD more frequently. Patients in cluster 2 had a higher incidence of heliotrope rashes. Patients in cluster 1 tended to have worse prognoses, wherein the 1-year and 5-year survival rates (81.1% and 78.4%, respectively) were lower than those in cluster 2 (97.6% and 95.2%, respectively), with p value 0.04 and 0.056 respectively. CONCLUSIONS: Through cluster analysis, different clinical phenotypes of MSA negative DM patients were determined. The prognoses of the two subgroups were different in terms of survival rate and cause of death.

Características clínicas, inmunológicas y daño de órganos en pacientes con miopatías inflamatorias idiopáticas / Organ damage clinical and immunological characteristics in patients with idiopathic inflammatory myopathies

Introducción: Las miopatías inflamatorias idiopáticas constituyen un grupo de enfermedades musculares caracterizadas por debilidad muscular crónica e inflamación muscular de etiología desconocida. Objetivo: Identificar las características clínicas e inmunológicas y su relación con el daño de órganos en los pacientes con miopatías inflamatorias idiopáticas. Métodos: Se realizó estudio observacional, descriptivo, transversal, en 52 pacientes con diagnóstico de miopatía inflamatoria idiopática, seguidos en la consulta protocolizada de Reumatología del Hospital Clínico Quirúrgico Hermanos Ameijeiras entre enero 2016 y enero 2017. Para las variables cualitativas se calcularon los porcentajes de cada grupo. Se utilizó Chi-cuadrado de Pearson (estadístico exacto de Fisher). Nivel de significación del 95 por ciento (α = 0,05) para relacionar la presencia de anticuerpos y el tipo de miopatía así como la presencia de manifestaciones clínicas de MII. Resultados: El 80,8 por ciento fueron mujeres y 86,5 por ciento de procedencia urbana. La edad media al comienzo fue 42,8 ± 13,2 años, tiempo de demora al diagnóstico de 8,8 ± 7,0 meses, tiempo medio de evolución de la enfermedad de 7,5 ± 7,1 años. El 80,8 por ciento estaba en remisión, 50 por ciento tenía anticuerpos específicos. La hipertensión arterial se encontró en 28,8 por ciento de los pacientes y 23,1 por ciento presentó neumonía intersticial. La artritis estuvo presente en 96,2 por ciento. El 26,9 por ciento presentaron anticuerpos específicos Jo-1 y 21,2 por ciento Ro 52. Conclusiones: Predominaron los pacientes del sexo femenino en la cuarta década de la vida de procedencia urbana, los anticuerpos específicos encontrados más frecuentes fue el anti Jo-1, asociado a la presencia de neumopatía intersticial(AU)

Introduction: Idiopathic inflammatory myopathies constitute a group of muscle diseases characterized by chronic muscle weakness and muscle inflammation of unknown etiology. Objective: To identify the clinical and immunological characteristics and their relationship with organ damage in patients with idiopathic inflammatory myopathies. Methods: An observational, descriptive, cross-sectional study was carried out in 52 patients with diagnosis of idiopathic inflammatory myopathy, followed in the protocolized consultation of Rheumatology at Hermanos Ameijeiras Clinical and Surgical Hospital from January 2016 to January 2017. For the qualitative variables, the percentages of each group were calculated. Pearson's Chi-square (Fisher's exact statistic) was used. 95percent significance level (α = 0.05) was used to relate the presence of antibodies and the type of myopathy as well as the presence of clinical manifestations of MII. Results: 80.8percent were women and 86.5percent of urban origin. The mean age at the beginning was 42.8 ± 13.2 years, time delay to diagnosis was 8.8 ± 7.0 months, mean time of evolution of the disease of 7.5 ± 7.1 years. 80.8percent were in remission, 50percent had specific antibodies. Hypertension was found in 28.8percent of the patients and 23.1percent had interstitial pneumonia. Arthritis was present in 96.2percent. 26.9percent had specific Jo1 antibodies and 21.2percent had Ro 52. Conclusions: Urban female patients in the fourth decade of life predominated, the most frequent specific antibodies found was anti-Jo-1, associated with the presence of interstitial lung disease(AU)

Characteristics of dermatomyositis patients with and without associated malignancy.

BACKGROUND: Dermatomyositis belongs to the rare idiopathic, inflammatory myositis group. A previously postulated link between some cases of dermatomyositis and malignancy has been established in recent years. Criteria suggestive of a malignancy association are still being explored. PATIENTS AND METHODS: We retrospectively analyzed data from 63 patients with dermatomyositis over a period of 15 years. RESULTS: The following criteria argue for cancer-associated dermatomyositis: older age (> 52 years [P = 0.001], > 65 years [P = 0.002], ≥ 75 years [P = 0.002]), shorter time between manifestation and diagnosis of dermatomyositis (malignancy group: 59 days vs. non-malignancy group: 137 days [P = 0.022]), typical skin involvement such as Gottron sign (P = 0.045), centrofacial erythema (P = 0.036) and typical erythema on the upper arms and forearms (P = 0.019), oropharyngeal involvement (P = 0.015) and increased ALT (P = 0.031). The following criteria argue for non-cancer-associated dermatomyositis: younger age (≤ 52 years [P = 0.001], 40-65 years [P = 0.045]) and pruritus (P = 0.026). CONCLUSIONS: The aforementioned criteria have been documented in the literature, but reported findings are heterogenous concerning the suitability of their markers for malignancy association. Small study populations, few prospective controlled studies, summarization of different forms of myositis and inconsistent use nomenclature contribute to biased results. Our study aims to make an important contribution toward the identification of risk factors in cancer-associated dermatomyositis.