Unveiling Cardiac Involvement in Juvenile Dermatomyositis Through Speckle-Tracking Echocardiography.

Early detection of cardiac involvement in Juvenile Dermatomyositis (JDM) is difficult due to the absence of clinical signs and symptoms, with systolic dysfunction often emerging in late stages and associated with a poor prognosis. This study aimed to employ two-dimensional speckle-tracking echocardiography (STE) for subclinical assessment of left ventricular (LV) systolic failure in JDM and explore potential associations between impaired LV systolic function (LV-GLS) and disease activity. A prospective study enrolled 20 healthy volunteers and 26 JDM patients (< 18 years old) without cardiac symptoms. Clinical data were collected from medical records, and echocardiograms were conducted by a pediatric cardiologist. Our study cohort demonstrated similar age to controls (13.5 ± .6 vs. 13.8 ± 4.7; p = 0.465). Median illness duration at echocardiography was 5 (1.5-17.5) years, and conventional echocardiography indicated normal LV ejection fraction (> 55%) in all participants. However, STE revealed lowered LV GLS in JDM patients (- 22.2 ± 4.1% vs. - 26.5 ± 5.3% p = 0.022). Pulse steroid users displayed lower GLS average values compared to non-users (ß = 4.99, 95% CI 1.34-8.64, p = 0.009). Negative correlations existed between LV-GLS and age at diagnosis (r = - 0.499; p = 0.011), diastolic parameters (E/E' ratio) and age at diagnosis (r = - 0.469; p = 0.018), as well as RV global strain and age at diagnosis (r = - 0.443; p = 0.024). Employing STE in JDM patients facilitated the identification of preclinical cardiac dysfunction. Given JDM patients' younger age, early myocardial damage detection through STE may impact treatment decisions and long-term cardiovascular prognosis.

Preclinical ocular microvascular changes in juvenile dermatomyositis: A pilot optical coherence tomography angiography study.

OBJECTIVES: To evaluate the macular and optic nerve head (ONH) vascular density, foveal avascular zone area, and outer retina and choriocapillaris flow in juvenile dermatomyositis (JDM) using optical coherence tomography angiography (OCTA). METHODS: Ten eyes of 10 patients with JDM and 15 age and sex-matched healthy controls were investigated in this prospective, cross-sectional study. The superficial capillary plexus (SCP) and deep capillary plexus (DCP), ONH, foveal avascular zone (FAZ) parameters, the flow area of the outer retina, and choriocapillaris were evaluated using OCTA. RESULTS: Vessel density (VD) of the parafovea (p = 0.036) and parafoveal subregions (p = 0.041 for superior hemifield, p = 0.031 for inferior hemifield, p = 0.012 for superior, p = 0.019 for nasal, p = 0.026 for inferior, and p = 0.048 for temporal) in DCP were significantly lower in the JDM group compared to healthy controls. A high inverse correlation between disease duration and these parameters was found except parafoveal superior VD in DCP. There was no significant difference between the groups in VD parameters of SCP and ONH, FAZ parameters, outer retina, and choriocapillaris flow area as well as thickness parameters. (p > 0.05 for all). Furthermore, ROC analysis revealed that all parafoveal DCP parameters showed good ability to differentiate JDM from healthy controls. CONCLUSIONS: We demonstrated a decreased vessel density in the deep parafoveal region in JDM. As a result, we hypothesized that OCTA could detect retinal microvascular changes in JDM patients who did not have clinical evidence of ocular involvement.

Favorable outcomes with reduced steroid use in juvenile dermatomyositis.

BACKGROUND: High-intensity glucocorticoid regimens are commonly used to induce and maintain remission in Juvenile Dermatomyositis but are associated with several adverse side-effects. Evidence-based treatment guidelines from North American and European pediatric rheumatology research societies both advocate induction with intravenous pulse steroids followed by high dose oral steroids (2 mg/kg/day), which are then tapered. This study reports the time to disease control with reduced glucocorticoid dosing. METHODS: We retrospectively reviewed the records at a single tertiary-care children's hospital of patients diagnosed with Juvenile Dermatomyositis between 2000 and 2014 who had a minimum of 2 years of follow-up. The primary outcome measure was time to control of muscle and skin disease. Additional outcome measures included glucocorticoid dosing, effect of treatment on height, frequency of calcinosis, and complications from treatment. RESULTS: Of the 69 patients followed during the study period, 31 fulfilled inclusion criteria. Median length of follow-up was 4.58 years, (IQR 3-7.5). Myositis control was achieved in a median of 7.1 months (IQR 0.9-63.4). Cutaneous disease control was achieved in a median of 16.7 months (IQR 4.3-89.5). The median starting dose of glucocorticoids was 0.85 mg/kg/day, (IQR 0.5-1.74). The median duration of steroid treatment was 9.1 months, (IQR 4.7-17.4), while the median duration of any pharmacotherapy was 29.2 months (IQR 10.4 to 121.3). Sustained disease control off medications was achieved in 21/31 (68%) patients by the end of review. Persistent calcinosis was identified in only one patient (3%). CONCLUSION: Current accepted treatment paradigms for Juvenile Dermatomyositis include oral glucocorticoids beginning at 2 mg/kg/day and reduced over a prolonged time period. However, our results suggest that treatment using reduced doses and duration with early use of steroid-sparing agents is comparably effective in achieving favorable outcomes in Juvenile Dermatomyositis.

COVID-19 and Myositis: What We Know So Far.

PURPOSE: Myositis as a rare manifestation of COVID-19 is only recently being reported. This review examines the current literature on COVID-19-induced myositis focusing on etiopathogenesis, clinical presentations, diagnostic practices, and therapeutic challenges with immunosuppression, and the difficulties experienced by rheumatologists in established myositis in the COVID-19 era. RECENT FINDINGS: COVID-19 is associated with a viral myositis attributable to direct myocyte invasion or induction of autoimmunity. COVID-19-induced myositis may be varied in presentation, from typical dermatomyositis to rhabdomyolysis, and a paraspinal affliction with back pain. It may or may not present with acute exponential elevations of enzyme markers such as creatine kinase (CK). Virus-mediated muscle inflammation is attributed to ACE2 (angiotensin-converting enzyme) receptor-mediated direct entry and affliction of muscle fibers, leading on to innate and adaptive immune activation. A greater recognition of the stark similarity between anti-MDA5-positive myositis with COVID-19 has thrown researchers into the alley of exploration - finding common etiopathogenic basis as well as therapeutic strategies. For patients with established myositis, chronic care was disrupted during the pandemic with several logistic challenges and treatment dilemmas leading to high flare rates. Teleconsultation bridged the gap while ushering in an era of patient-led care with the digital transition to tools of remote disease assessment. COVID-19 has brought along greater insight into unique manifestations of COVID-19-related myositis, ranging from direct virus-induced muscle disease to triggered autoimmunity and other etiopathogenic links to explore. A remarkable shift in the means of delivering chronic care has led patients and caregivers worldwide to embrace a virtual shift with teleconsultation and opened doorways to a new era of patient-led care.

Efficacy of aqua-based plyometric exercises in the rehabilitation of patients with juvenile dermatomyositis: A randomized crossover pilot study.

BACKGROUND: Patients with juvenile dermatomyositis (JDM) experience muscle weakness, tiredness, and loss of energy, which restrict their abilities in performance of their daily living activities. OBJECTIVE: To explore the effect of aquatic-based plyometric (Aqua-PLYO) exercises on muscle strength, fatigue, and functional ability in patients with JDM. METHODS: This was a randomized, single-blind, crossover pilot study that included 16 patients with JDM (age 13.44 ± 2.85 years). They were assigned randomly to receive either the Aqua-PLYO exercises (n = 8) or the standard outpatient care (SoC ; n = 8) first. After a 1-month washout, the treatment was reversed. Lower limb muscle strength, fatigue perception, functional ability, and disease activity were evaluated before and after each treatment period. RESULTS: Irrespective of the treatment order, the Aqua-PLYO treatment yielded greater improvement in muscle strength (hip flexors and abductors [P < 0.001] or knee flexors [P < 0.001] and extensors [P = 0.0008]), fatigue perception (P < 0.001), functional ability (P = 0.009), and disease activity (P = 0.0001) than the SoC treatment. By using the shortest confidence intervals (100[1-2α]%) of the difference, the average bioequivalence of the Aqua-PLYO and SoC has not been established at P = 0.05, because the upper and lower confidence bounds of all outcomes were not between the acceptance limits. No period or carryover effects were detected in all outcomes. CONCLUSION: The Aqua-PLYO exercise protocol as implemented in this study is safe, feasible, and well-tolerated in patients with JDM and seemingly useful to help increase muscle strength, reduce fatigue, and enhance functional ability in such a patient population.

Systemic lupus erythematosus overlapping dermatomyositis owing to a heterozygous TREX1 Asp130Asn missense mutation.

The 3' repair exonuclease 1 (TREX1) gene encodes a nuclear protein with 3' exonuclease activity, and the mutations have been associated with autoimmune diseases. Herein, we performed genetic analysis for the TREX1 gene in 55 patients with systemic lupus erythematosus (SLE). We identified one SLE patient with overlapping dermatomyositis having a heterozygous p.Asp130Asn mutation in the TREX1 gene. The patient had a high level of serum interferon (IFN)-α compared with that in healthy controls and other patients with SLE. In addition, the patient expressed elevated IFN signature genes compared with healthy controls. Our molecular dynamics simulation of the TREX1 protein in a complex with double-stranded DNA revealed that the D130N mutant causes significant changes in the active site's interaction network. One of our cases exhibited a heterozygous TREX1 p.Asp130Asn mutation that contributed to the type I IFN pathway, which may lead to the development of a severe SLE phenotype.

Bone mineral density and explanatory factors in children and adults with juvenile dermatomyositis at long term follow-up; a cross sectional study.

BACKGROUND: Juvenile dermatomyositis (JDM) is the most common idiopathic inflammatory myopathy in children and adolescents. Both the disease and its treatment with glucocorticoids may negatively impact bone formation. In this study we compare BMD in patients (children/adolescence and adults) with long-standing JDM with matched controls; and in patients, explore how general/disease characteristics and bone turnover markers are associated with BMD. METHODS: JDM patients (n = 59) were examined median 16.8y (range 6.6-27.0y) after disease onset and compared with 59 age/sex-matched controls. Dual-energy X-ray absorptiometry (DXA) was used to measure BMD of the whole body and lumbar spine (spine) in all participants, and of ultra-distal radius, forearm and total hip in participants ≥20y only. Markers of bone turnover were analysed, and associations with outcomes explored. RESULTS: Reduced BMD Z-scores (<-1SD) were found in 19 and 29% of patients and 7 and 9% of controls in whole body and spine, respectively (p-values < 0.05). BMD and BMD Z-scores for whole body and spine were lower in all patients and for < 20y compared with their respective controls. In participants ≥20y, only BMD and BMD Z-score of forearm were lower in the patients versus controls. In patients, BMD Z-scores for whole body and/or spine were found to correlate negatively with prednisolone use at follow-up (yes/no) (age < 20y), inflammatory markers (age ≥ 20y) and levels of interferon gamma-induced protein 10 (IP-10) (both age groups). In all patients, prednisolone use at follow-up (yes/no) and age ≥ 20y were independent correlates of lower BMD Z-scores for whole body and spine, respectively. CONCLUSION: In long-term JDM, children have more impairment of BMD than adults in spine and whole-body. Associations with BMD were found for both prednisolone and inflammatory markers, and a novel association was discovered with the biomarker of JDM activity, IP-10.

Forced vital capacity predicts the survival of interstitial lung disease in anti-MDA5 positive dermatomyositis: a multi-centre cohort study.

OBJECTIVES: Anti-melanoma differentiation-associated gene 5 (MDA5) positive DM is a life-threatening disease often complicated with rapidly progressive interstitial lung disease (ILD). This study aimed to establish and validate a clinical prediction model for 6-month all-cause mortality in Chinese patients with anti-MDA5 positive DM-ILD. METHODS: We conducted a retrospective observational study using a single-centre derivation cohort and a multicentre validation cohort. Hospitalized DM patients with positive anti-MDA5 antibody and ILD course ≤3 months on admission were included. Patients' baseline characteristics were described and compared between the deceased and survivors by univariable Cox regression. Optimal cut-off values were defined by the 'survminer' R package for significant continuous variables. Independent prognostic factors were determined by the final multivariable Cox regression model chosen by backward stepwise algorithm, which could be reproduced in both cohorts. The Kaplan-Meier survival analyses based on the derived predictor were conducted. RESULTS: A total of 184 and 81 eligible patients were included with a cumulative 40.8 and 40.7% 6-month mortality in the derivation and validation cohorts, respectively. Based on multivariable Cox regression, the prognostic factor at baseline was identified and validated as three-category forced vital capacity (FVC)%: FVC% ≥50%, FVC% <50%, unable to perform. This significantly distinguishes three risk stages with mortalities of 15.3, 46.8, 97.4% in the derivation cohort, and 14.9, 58.3, 86.4 in the validation cohort, respectively (all P <0.05). CONCLUSION: The validated FVC%-based categorical predictor in anti-MDA5 positive DM-ILD is helpful for risk stratification in clinical practice and might facilitate cohort enrichment for future trials.

Clinical features of anti-synthetase syndrome associated interstitial lung disease: a retrospective cohort in China.

BACKGROUND: Anti-synthetase syndrome (ASSD) is a chronic autoimmune condition characterized by antibodies directed against an aminoacycl transfer RNA synthetase (ARS) along with a group of clinical features including the classical clinical triad: inflammatory myopathy, arthritis, and interstitial lung disease (ILD). ASSD is highly heterogenous due to different organ involvement, and ILD is the main cause of mortality and function loss, which presents as different patterns when diagnosed. We designed this retrospective cohort to describe the clinical features and disease behaviour of ASSD associated ILD. METHODS: Data of 108 cases of ASSD associated ILD were retrospectively collected in Beijing Chaoyang Hospital from December 2017 to March 2019. Data were obtained from the Electronic Medical Record system. Patients were divided into 5 groups according to distinct aminoacyl tRNA synthetase (ARS) antibodies. RESULTS: Overall, 108 consecutive patients were recruited. 33 were JO-1 positive, 30 were PL-7 positive, 23 were EJ positive, 13 were PL-12 positive and 9 were OJ positive. The JO-1 (+) group had a significant higher rate of mechanic's hand (57.6%) than other 4 groups. Polymyositis/dermatomyositis (PM/DM) was diagnosed in 25 (23.1%) patients and no difference was observed among the 5 groups. The PL-7 (+) group had a higher frequency of UIP pattern (13.3%) than the other 4 groups but the difference was not significant, and the EJ (+) group had the most frequent OP pattern (78.2%), which was significantly higher than the PL-7 (+) (P < 0.001) and PL-12 (+) groups (P = 0.025). The median follow-up time was 10.7 months, during which no patients died. All received prednisone treatment, with or without immunosuppressants. At the 6-month follow-up, 96.3% of all patients (104/108) had a positive response to therapy, the JO-1 (+) and EJ (+) groups had a significantly higher improvement of forced vital capacity than the other 3 groups (P < 0.05), and the PL-7 group had the lowest FVC improvement (P < 0.05). The JO-1 (+) group and EJ (+) group had significantly higher anti-Ro-52 positive occurrence than the other 3 groups (P < 0.05). CONCLUSION: Anti PL-7 antibody had the same frequency as anti-JO-1 in ASSD-ILD, in which the ILD pattern was different with distinct anti-ARS antibodies. Most ASSD-ILD had a positive response to steroid therapies, with or without immunosuppressants. The PL-7 (+) group had the highest occurrence of UIP pattern, and a significantly lower response to therapy.

Elevated carcinoembryonic antigen predicts rapidly progressive interstitial lung disease in clinically amyopathic dermatomyositis.

OBJECTIVES: The present study aimed to determine the correlation between serum carcinoembryonic antigen (CEA) level and the severity of interstitial lung disease (ILD) in clinically amyopathic DM (CADM) patients. METHODS: We performed a retrospective study including 41 Chinese CADM patients without malignancy. Serum CEA levels, clinical and laboratory findings were collected. Association tests between CEA levels and disease activity parameters were performed. RESULTS: Among the 41 patients, 16 (39.0%) developed rapidly progressive (RP)-ILD; of them, 14 (87.5%) had elevated serum CEA levels. Multivariate logistic regression analysis indicated that an elevated serum CEA level was an independent risk factor for RP-ILD. The incidence of elevated CEA level was significantly higher in patients with RP-ILD than in those without RP-ILD (87.5 vs 16.0%, P < 0.001). Furthermore, CEA levels were higher in patients with CADM with RP-ILD [26.87 (6.71) µg/l] than in those without RP-ILD [3.23 (0.64) µg/l] (P < 0.001). CEA levels in CADM patients were associated with the ferritin, alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase levels, and CT scores of the lungs. Also, elevated CEA levels are related to the organizing pneumonia pattern and lower lung zone consolidation in high-resolution CT. Moreover, the cumulative survival rate was significantly lower (68.4 vs 31.6%, P < 0.001) in the group with a CEA level >8.75 µg/l than that in the group with a CEA level <8.75 µg/l. CONCLUSIONS: An elevated serum CEA level is common in patients with CADM, and a higher serum CEA level is a powerful indicator of RP-ILD and poor prognosis in those patients.

The Vasculopathy of Juvenile Dermatomyositis: Endothelial Injury, Hypercoagulability, and Increased Arterial Stiffness.

OBJECTIVE: Vasculopathy is considered central to the pathogenesis of juvenile dermatomyositis (DM) and is associated with severe extramuscular manifestations. We undertook this study to investigate the hypothesis that the vasculopathy of juvenile DM can be noninvasively tracked by examining biomarkers of endothelial injury, subclinical inflammation, hypercoagulability, and vascular arterial stiffness. METHODS: The study population was a UK cohort of children with juvenile DM. Circulating endothelial cells (CECs) and microparticles (MPs) were identified using immunomagnetic bead extraction and flow cytometry, respectively. Plasma thrombin generation was determined using a fluorogenic assay. Cytokine and chemokine levels were measured by electrochemiluminescence. Arterial stiffness was assessed using pulse wave velocity (PWV). Results were expressed as the median and interquartile range (IQR), and statistical significance was assessed using nonparametric analyses. RESULTS: Ninety patients with juvenile DM and 79 healthy control subjects were included. The median age of the patients was 10.21 years (IQR 6.68-13.40), and the median disease duration was 1.63 years (IQR 0.28-4.66). CEC counts were higher in all patients with juvenile DM compared to controls (median 96 cells/ml [IQR (40-192] and 12 cells/ml [IQR 8-24], respectively; P < 0.0001). Circulating MP numbers were also significantly higher in patients with active juvenile DM compared to controls (median 204.7 × 103 /ml [IQR 87.9-412.6] and 44.3 × 103 /ml [IQR 15.0-249.1], respectively; P < 0.0001). MPs were predominantly of platelet and endothelial origin. Enhanced plasma thrombin generation was demonstrated in patients with active juvenile DM compared to those with inactive disease (P = 0.0003) and controls (P < 0.0001). Carotid-radial PWV adjusted for age was increased in patients with juvenile DM compared to controls (P = 0.003). CONCLUSION: We observed increased endothelial injury and increased levels of proinflammatory cytokines in patients with active juvenile DM. MP profiles reflected distinct disease activity status in juvenile DM and are markers of vascular pathology, platelet activation, and thrombotic propensity. Ongoing long-term vascular injury may result in increased arterial stiffness in patients with juvenile DM.

Cytokeratin 19 fragment is associated with severity and poor prognosis of interstitial lung disease in anti-MDA5 antibody-positive dermatomyositis.

OBJECTIVES: In the present study, we aimed to assess the clinical significance of cytokeratin 19 fragment (CYFRA21-1) in patients with anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive DM-interstitial lung disease (MDA5-DM-ILD). METHODS: A total of 73 MDA5-DM-ILD patients were retrospectively analysed in this work. Their clinical characteristics, including clinical manifestations, laboratory findings, peripheral blood lymphocyte subsets and lung function, were compared between patients with acute/subacute interstitial pneumonia (A/SIP) and chronic interstitial pneumonia (CIP). The level of serum CYFRA21-1 was also compared between the above-mentioned two groups of patients, and its association with the clinical features and mortality of MDA5-DM-ILD was also evaluated. RESULTS: Of the 73 MDA5-DM-ILD patients, 26 patients exhibited the A/SIP pattern. The level of serum CYFRA21-1 was higher in MDA5-DM patients with A/SIP compared with the CIP group (P = 0.009). Lower oxygenation index (OI), CD3+CD4+ T cell counts and percentage of CD3+CD4+ cells were also observed in MDA5-DM patients with A/SIP compared with the CIP group. Higher serum CYFRA21-1, lower OI, and lower zone consolidation were associated with a higher risk of A/SIP in MDA5-DM-ILD. In addition, 38 decedents with MDA5-DM-ILD exhibited a greater level of CYFRA21-1 compared with 35 survivors (P < 0.001). Furthermore, it was a prognostic factor and also associated with a higher mortality rate (log-rank test, P < 0.001). CONCLUSIONS: CYFRA21-1 could be a useful serum indicator associated with occurrence of A/SIP in MDA5-DM-ILD. Moreover, it was associated with a poor survival in MDA5-DM-ILD patients.

Staphylococcus-associated acute glomerulonephritis in a patient with dermatomyositis.

Staphylococcus-associated glomerulonephritis (SAGN) occurs as a complication of staphylococcal infection elsewhere in the body. Dermatomyositis (DM) can be associated with glomerulonephritis due to the disease per se. We report a case of a 40-year-old male patient with DM who presented with acute kidney injury, and was initially pulsed with methylprednisolone for 3 days, followed by dexamethasone equivalent to 1 mg/kg/day prednisolone. He was subsequently found to have SAGN on kidney biopsy along with staphylococcus bacteraemia and left knee septic arthritis. With proof of definitive infection, intravenous immunoglobulin 2 g/kg over 2 days was given and steroids were reduced. He was treated with intravenous vancomycin. With treatment, the general condition of the patient improved. On day 38, he developed infective endocarditis and died of congestive heart failure subsequently. Undiagnosed staphylococcal sepsis complicating a rheumatological disease course can lead to complications like SAGN, infective endocarditis and contribute to increased morbidity and mortality, as is exemplified by our case.

ECG Changes Through Immunosuppressive Therapy Indicate Cardiac Abnormality in Anti-MDA5 Antibody-Positive Clinically Amyopathic Dermatomyositis.

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody, a dermatomyositis (DM)-specific antibody, is strongly associated with interstitial lung disease (ILD). Patients with idiopathic inflammatory myopathy (IIM) who are anti-MDA5 antibody positive [anti-MDA5 (+)] often experience chest symptoms during the active disease phase. These symptoms are primarily explained by respiratory failure; nevertheless, cardiac involvement can also be symptomatic. Thus, the aim of this study was to investigate cardiac involvement in anti-MDA5 (+) DM. A total of 63 patients with IIM who underwent electrocardiography (ECG) and ultrasound cardiography (UCG) during the active disease phase from 2016 to 2021 [anti-MDA5 (+) group, n = 21; anti-MDA5-negative (-) group, n = 42] were enrolled in the study, and their clinical charts were retrospectively reviewed. The ECG and UCG findings were compared between the anti-MDA5 (+) and anti-MDA5 (-) groups. All anti-MDA5 (+) patients had DM with ILD. The anti-MDA5 (+) group showed more frequent skin ulcerations and lower levels of leukocytes, muscle enzymes, and electrolytes (Na, K, Cl, and Ca) than the anti-MDA5 (-) group. According to the ECG findings obtained during the active disease phase, the T wave amplitudes were significantly lower for the anti-MDA5 (+) group than for the anti-MDA5 (-) group (I, II, and V4-6 lead; p < 0.01; aVF and V3, p < 0.05). However, the lower amplitudes were restored during the remission phase. Except for the E wave, A wave and Sep e', the UCG results showed no significant differences between the groups. Four patients with anti-MDA5 (+) DM had many leads with lower T wave and cardiac abnormalities (heart failure, diastolic dysfunction, myocarditis) on and after admission. Though anti-MDA5 (+) patients clinically improved after immunosuppressive therapy, some of their ECG findings did not fully recover in remission phase. In conclusion, anti-MDA5 (+) DM appears to show cardiac involvement (electrical activity and function) during the active phase. Further studies are necessary to clarify the actual cardiac condition and mechanism of these findings in patients with anti-MDA5 (+) DM.

Risk factors associated with Pneumocystis jirovecii pneumonia in juvenile myositis in North America.

OBJECTIVES: Pneumocystis jirovecii pneumonia (PJP) is associated with significant morbidity and mortality in adult myositis patients; however, there are few studies examining PJP in juvenile myositis [juvenile idiopathic inflammatory myopathy (JIIM)]. The purpose of this study was to determine the risk factors and clinical phenotypes associated with PJP in JIIM. METHODS: An research electronic data capture (REDCap) questionnaire regarding myositis features, disease course, medications and PJP infection characteristics was completed by treating physicians for 13 JIIM patients who developed PJP (PJP+) from the USA and Canada. Myositis features and medications were compared with 147 JIIM patients without PJP (PJP-) from similar geographic regions who enrolled in National Institutes of Health natural history studies. RESULTS: PJP+ patients were more often of Asian ancestry than PJP- patients [odds ratio (OR) 8.7; 95% CI 1.3, 57.9]. Anti- melanoma differentiation associated protein 5 (MDA5) autoantibodies (OR 12.5; 95% CI 3.0, 52.4), digital infarcts (OR 43.8; 95% CI 4.2, 460.2), skin ulcerations (OR 12.0; 95% CI 3.5, 41.2) and interstitial lung disease (OR 10.6; 95% CI 2.1, 53.9) were more frequent in PJP+ patients. Before PJP diagnosis, patients more frequently received pulse steroids, rituximab and more immunosuppressive therapy compared with PJP- patients. Seven PJP+ patients were admitted to the intensive care unit and four patients died due to PJP or its complications. CONCLUSIONS: PJP is a severe infection in JIIM that can be associated with mortality. Having PJP was associated with more immunosuppressive therapy, anti-MDA5 autoantibodies, Asian race and certain clinical features, including digital infarcts, cutaneous ulcerations and interstitial lung disease. Prophylaxis for PJP should be considered in juvenile myositis patients with these features.

Sensitivity and specificity of single and combined clouds analyses compared with quantitative motor unit potential analysis.

INTRODUCTION: Turns-amplitude, number of small segments (NSS)-activity, and envelope-activity clouds are three methods of electromyography (EMG) interference pattern analysis. Our objective was to evaluate the sensitivity and specificity of each individual cloud analysis and combined clouds analysis to compare with that of quantitative motor unit potential (QMUP) analysis. METHODS: A total of 379 muscles from 100 patients were analyzed by both QMUP and clouds analyses. Calculation of sensitivity and specificity was based on the clinical diagnosis as the "gold standard." RESULTS: For discrimination of abnormal vs normal and neuropathic vs non-neuropathic, combined clouds analysis had greater sensitivity than QMUP analysis and any single cloud analysis, but there were no differences in specificity. For discrimination of myopathic vs non-myopathic, combined clouds analysis and single cloud analysis had greater sensitivity than QMUP analysis, but there were no differences in specificity. DISCUSSION: Combined clouds analysis was superior to QMUP and each single cloud analysis for distinguishing normal, myopathic, and neuropathic muscles.

Study of Tofacitinib in Refractory Dermatomyositis: An Open-Label Pilot Study of Ten Patients.

OBJECTIVE: This open-label 12-week study was conducted to evaluate the efficacy and safety of tofacitinib, a JAK inhibitor, in treatment-refractory active dermatomyositis (DM). METHODS: Tofacitinib in extended-release doses of 11 mg was administered daily to 10 subjects with DM. Prior to treatment, a complete washout of all steroid-sparing agents was performed. The primary outcome measure was assessment of disease activity improvement based on the International Myositis Assessment and Clinical Studies group definition of improvement. Response rate was measured as the total improvement score according to the 2016 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) myositis response criteria. Secondary outcome measures included Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI) scores, chemokine levels, immunohistochemical analysis of STAT1 expression in the skin, RNA sequencing analysis, and safety. RESULTS: At 12 weeks, the primary outcome was met in all 10 subjects. Five (50%) of 10 subjects experienced moderate improvement in disease activity, and the other 50% experienced minimal improvement according to the 2016 ACR/EULAR myositis response criteria. The secondary outcome of the mean change in the CDASI activity score over 12 weeks was statistically significant (mean ± SD 28 ± 15.4 at baseline versus 9.5 ± 8.5 at 12 weeks) (P = 0.0005). Serum chemokine levels of CXCL9/CXCL10 showed a statistically significant change from baseline. A marked decrease in STAT1 signaling in association with suppression of interferon target gene expression was demonstrated in 3 of 9 skin biopsy samples from subjects with dermatomyositis. The mean ± SD level of creatine kinase in the 10 subjects at baseline was 82 ± 34.8 IU/liter, highlighting that disease activity was predominantly located in the skin. CONCLUSION: This is the first prospective, open-label clinical trial of tofacitinib in DM that demonstrates strong clinical efficacy of a pan-JAK inhibitor, as measured by validated myositis response criteria. Future randomized controlled trials using JAK inhibitors should be considered for treating DM.

Prognostic values of anti-Ro52 antibodies in anti-MDA5-positive clinically amyopathic dermatomyositis associated with interstitial lung disease.

OBJECTIVE: Anti-Ro52 antibody often co-occurs with anti-Jo1 antibody in antisynthetase syndrome and their co-occurrence correlates with a more aggressive clinical phenotype and poorer prognosis. The strong association of anti-Ro52 antibody with anti-melanoma differentiation-associated protein-5 (anti-MDA5) antibody has been indicated in juvenile myositis. The aim of this study was to assess the clinical significance of anti-Ro52 antibody in a cohort of adult patients with anti-MDA5-positive clinically amyopathic dermatomyositis with interstitial lung disease (CADM-ILD). METHODS: We assessed a cohort of 83 consecutive patients with anti-MDA5-positive CADM-ILD. Anti-MDA5 antibodies and anti-Ro52 antibodies were detected in immunoblotting and semi-quantitatively analysed by densitometry. Clinical features and the 24 month survival were compared between anti-MDA5-positive patients with and without anti-Ro52 antibodies. RESULTS: Anti-Ro52 antibodies were found in 74.7% of anti-MDA5-positive CADM-ILD patients and were associated with an increased frequency of rapidly progressive interstitial lung disease (RP-ILD; 54.8% vs 23.8%; P = 0.014) and cutaneous ulcerations (27.4% vs 4.8%; P = 0.033). The cumulative 24 month survival rate tended to be lower in patients with anti-Ro52 antibodies than patients without (59.9% vs 85.7%; P = 0.051). The combination of anti-Ro52 antibody status and anti-MDA5 antibody levels further stratified patients' survival rates, showing that the survival rate of patients who were dual positive for anti-MDA5 antibody and anti-Ro52 antibody was significantly lower than patients with mild positive anti-MDA5 antibody alone (59.9% vs 100%; P = 0.019). CONCLUSION: Anti-Ro52 antibody is highly prevalent in anti-MDA5-positive CADM-ILD patients and their coexistence correlates with a subgroup of patients with more aggressive phenotypes. The combination of anti-MDA5 antibody levels and anti-Ro52 antibody status could help to predict patients' prognosis and guide risk-based therapy.

Ventricular arrhythmia predicts poor outcome in polymyositis/dermatomyositis with myocardial involvement.

OBJECTIVE: Myocardial involvement (MCI) is known to increase morbidity and mortality in polymyositis (PM) and dermatomyositis (DM). This study aims to investigate whether complicating with ventricular arrhythmia (VA) predicts poor outcomes in patients with PM/DM-related myocardial involvement (PM/DM-MCI). METHODS: We reviewed all PM/DM-MCI patients admitted to Peking Union Medical College Hospital from October 1997 to April 2019. VA and the other possible risk factors for the composite endpoint, including death from any cause and rehospitalization for cardiac causes, were analyzed. RESULTS: A total of 75 PM/DM-MCI patients (44 PM and 31 DM) were enrolled, of which 27 (36%) met the composite endpoint during a median follow-up of 24 months. Independent prognostic factors for the composite endpoint include VA [HR 4.215, 95% CI (1.737, 10.230)], NT-proBNP > 3415 pg/ml [HR 2.606, 95% CI (1.203, 5.646)], interstitial lung disease [HR 2.688, 95% CI (1.209, 5.978)], and anti-cardiac remodelling therapy [HR 0.302, 95% CI (0.115, 0.792)]. The 3-year event-free survival rate of patients without VA was significantly higher than that of patients with VA (63.3% vs 40.7%, P = 0.034). Skin lesions [OR 0.163, 95% CI (0.051, 0.523)] and positive antimitochondrial antibody [OR 3.484, 95% CI (1.192, 10.183)] were independent predictors of VA. CONCLUSION: VA provides prognostic insights for PM/DM-MCI patients and predicts poor outcome. Polymyositis and positive antimitochondrial antibody are closely associated with the presence of VA in PM/DM-MCI.