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International Journal of Rheumatic... May 2024
Topics: Humans; Male; Autoantibodies; Biomarkers; Dermatomyositis; Fatal Outcome; Hypertension, Pulmonary; Interferon-Induced Helicase, IFIH1; Pulmonary Arterial Hypertension; Child
PubMed: 38720426
DOI: 10.1111/1756-185X.15180 -
Frontiers in Neurology 2024Inflammatory myopathy with mitochondrial pathology (IM-Mito) is a rare condition described in a few case series, and it is not clear whether it is a specific disease or...
INTRODUCTION
Inflammatory myopathy with mitochondrial pathology (IM-Mito) is a rare condition described in a few case series, and it is not clear whether it is a specific disease or a variant of Inclusion Body Myositis (IBM). Radiological data of IM-Mito patients has only been evaluated in one study.
AIM
To analyze whole-body muscle magnetic resonance imaging (MRI) features in patients with IM-Mito compared with individuals with IBM.
METHODS
Fourteen IM-Mito and ten IBM patients were included. IM-Mito was defined by endomysial inflammatory infiltrate, presence of at least 1% of Cytochrome C Oxidase negative fibers, and absence of rimmed vacuoles in muscle biopsy; and IBM was defined by the presence of dystrophic muscular abnormalities, endomysial inflammatory infiltrate, and rimmed vacuoles. Patients underwent clinical evaluation and whole-body muscle MRI to determine the presence of edema, and fatty infiltration in various muscles.
RESULTS
Muscle imaging abnormalities were asymmetric in most patients with IM-Mito and IBM. Muscles with the highest average degree of fatty infiltration in both conditions were the quadriceps and medial gastrocnemius. Most patients with IM-Mito and IBM showed imaging patterns of rectus femoris relatively spared compared to other quadriceps muscles. The flexor digitorum profundus was the most affected muscle of the upper limbs in both IBM and IM-Mito.
DISCUSSION
Although the results suggest some similarities in muscle imaging features between IM-Mito and IBM, there remains uncertainty whether these two conditions are part of the same clinical spectrum.
PubMed: 38715692
DOI: 10.3389/fneur.2024.1386293 -
Seminars in Respiratory and Critical... Jun 2024Antisynthetase syndrome (ASyS) is now a widely recognized entity within the spectrum of idiopathic inflammatory myopathies. Initially described in patients with a triad... (Review)
Review
Antisynthetase syndrome (ASyS) is now a widely recognized entity within the spectrum of idiopathic inflammatory myopathies. Initially described in patients with a triad of myositis, arthritis, and interstitial lung disease (ILD), its presentation can be diverse. Additional common symptoms experienced by patients with ASyS include Raynaud's phenomenon, mechanic's hand, and fever. Although there is a significant overlap with polymyositis and dermatomyositis, the key distinction lies in the presence of antisynthetase antibodies (ASAs). Up to 10 ASAs have been identified to correlate with a presentation of ASyS, each having manifestations that may slightly differ from others. Despite the proposal of three classification criteria to aid diagnosis, the heterogeneous nature of patient presentations poses challenges. ILD confers a significant burden in patients with ASyS, sometimes manifesting in isolation. Notably, ILD is also often the initial presentation of ASyS, requiring pulmonologists to remain vigilant for an accurate diagnosis. This article will comprehensively review the various aspects of ASyS, including disease presentation, diagnosis, management, and clinical course, with a primary focus on its pulmonary manifestations.
Topics: Humans; Myositis; Lung Diseases, Interstitial; Autoantibodies; Diagnosis, Differential
PubMed: 38710221
DOI: 10.1055/s-0044-1785536 -
EJIFCC Apr 2024Creatine kinase (CK) and aldolase are markers traditionally used in the study of muscle damage (MD). As CK determination is more specific to muscle damage, the demand...
BACKGROUND-AIM
Creatine kinase (CK) and aldolase are markers traditionally used in the study of muscle damage (MD). As CK determination is more specific to muscle damage, the demand for both determinations in routine laboratory tests would entail an extra cost.
METHODS
Retrospective observational study conducted between 2019-2020. CK and aldolase concentrations from 218 patients were studied.ROC curves were analyzed for CK and aldolase for muscle damage detection. Cut-off values were selected for both strategies. Specifity of CK and aldolase for dermatomyositis or polymyositis diagnosis in our population was studied using the McNemar's test.
RESULTS
The area under the ROC curve (AUC) for total CK was 0.716 (95%CI: 0.651-0.775), for CK in males it was 0.703 (95%CI: 0.592-0.799), and for CK in females was 0.719 (95%CI: 0.636-0.793). For aldolase, AUC was 0.505 (95%CI: 0.437-0.573). Optimized cut-off points for each determination were: 112 U/L for CK in men, with a sensitivity of 73.9% (95%CI: 51.6-89.8) and a specificity of 49.2% (95%CI: 35.9-62.5); 88 U/L for CK in women, with a sensitivity of 75.0% (95%CI: 57.8-87.9) and specificity of 50.5% (95%CI: 40.4-60.6); and 5.6 U/L for aldolase, with a sensitivity of 61.0% (95%CI: 53.2-68.8) and a specificity of 38.8% (95%CI: 26.5-52.6).Regarding the individuals diagnosed with dermatomyositis or polymyositis, 66.7% and 44.4% of them were correctly classified as pathological by CK and aldolase results, respectively. McNemar's test did not reveal significant differences.
CONCLUSION
The determination of CK offers a better diagnostic performance of MD and, in addition, does not present significant differences regarding the determination of aldolase in cases of polymyositis and dermatomyositis. Therefore, the single determination of CK would be sufficient for MD screening.
PubMed: 38706738
DOI: No ID Found -
Journal of the American Academy of... May 2024
PubMed: 38704031
DOI: 10.1016/j.jaad.2024.03.052 -
Rheumatology (Oxford, England) May 2024This study aimed to establish a screening model for differentiating anti-synthetase syndrome (ASS) from other antinuclear antibody (ANA)-associated rheumatic diseases...
OBJECTIVE
This study aimed to establish a screening model for differentiating anti-synthetase syndrome (ASS) from other antinuclear antibody (ANA)-associated rheumatic diseases (AARD) using a combination of cytoplasmic and non-cytoplasmic ANA (ncANA) patterns.
METHODS
This retrospective observational study included patients with AARDs such as systemic lupus erythematosus (SLE), systemic sclerosis (SSc), Sjögren's syndrome (SS), mixed connective tissue disease (MCTD), and polymyositis/dermatomyositis (PM/DM) who underwent ANA screening between April 2012 and December 2021. Variables included age, sex, ANA patterns (Cytoplasmic and ncANA), and titers. Logistic regression analysis of Cytoplasmic and ncANA patterns was performed to differentiate ASS from other AARDs.
RESULT
The 981 diagnosed cases of AARDs consisted of SS (n = 451), SSc (n = 264), SLE (n = 201), PM/DM (n = 104), MCTD (n = 52), and ASS, including PM/DM (n = 64). Of these, 155 patients had ≥2 overlapping diseases; however, there was no overlap between AARDs and ASS. ASS is more likely to occur when the cytoplasmic titer is positive and the ncANA <320. Receiver operating characteristic (ROC) analysis of the Cytoplasmic and ncANA range revealed an area under the ROC curve (AUC) of 0.885 (95% CI: 0.844 to 0.927).
CONCLUSION
It is important to detect cytoplasmic patterns as an ANA screening test for ASS diagnosis, even if the titer is low. Additionally, combining the cytoplasmic and ncANA patterns yields more accurate ASS screening results.
PubMed: 38696756
DOI: 10.1093/rheumatology/keae245 -
Journal of Autoimmunity Jun 2024The link between type I IFN and adaptive immunity, especially T-cell immunity, in JDM still remained largely unclear. This study aimed to understand the effect of...
The link between type I IFN and adaptive immunity, especially T-cell immunity, in JDM still remained largely unclear. This study aimed to understand the effect of elevated type I IFN signaling on CD8 T cell-associated muscle damage in juvenile dermatomyositis (JDM). This study used flow cytometry (FC) and RT‒PCR were used to examine the circulating cell ratio and type I IFN response. And scRNA-seq was used to examine peripheral immunity in 6 active JDM patients, 3 stable JDM patients, 3 juvenile IMNM patients and 3 age-matched healthy children. In vivo validation experiments were conducted using a mouse model induced by STING agonists and an experimental autoimmune myositis model (EAM). In vitro experiments were conducted using isolated CD8 T-cells from JDM patients and mice. We found that active JDM patients showed an extensive type I IFN response and a decreased CD8 T-cell ratio in the periphery (P < 0.05), which was correlated with muscle involvement (P < 0.05). Both new active JDM patients and all active JDM patients showed decreased CD8 TCM cell ratios compared with age and gender matched stable JDM patients (P < 0.05). Compared with new pediatirc systemic lupus erythematosus (SLE) patients, new active JDM patients displayed decreased CD8 T-cell and CD8 TCM cell ratios (P < 0.05). Active JDM patient skeletal muscle biopsies displayed an elevated type I IFN response, upregulated MHC-I expression and CD8 T-cell infiltration, which was validated in EAM mice. sc-RNAseq demonstrated that type I IFN signalling is the kinetic factor of abnormal differentiation and enhances the cytotoxicity of peripheral CD8 T cells in active JDM patients, which was confirmed by in vivo and in vitro validation experiments. In summary, the elevated type I IFN signalling affected the differentiation and function of CD8 T cells in active JDM patients. Skeletal muscle-infiltrating CD8 T cells might migrate from the periphery under the drive of type I IFN and increased MHC I signals. Therapies targeting autoantigen-specific CD8 T cells may represent a potential new treatment direction.
Topics: Humans; CD8-Positive T-Lymphocytes; Interferon Type I; Animals; Muscle, Skeletal; Mice; Signal Transduction; Autoantigens; Female; Dermatomyositis; Male; Child; Disease Models, Animal; Adolescent; Child, Preschool
PubMed: 38692172
DOI: 10.1016/j.jaut.2024.103232 -
JAMA Dermatology Jun 2024
Topics: Humans; Dermatomyositis; Lung Diseases, Interstitial; Methotrexate; Female; Middle Aged; Male; Adult; Dermatologic Agents; Risk Factors; Aged
PubMed: 38691354
DOI: 10.1001/jamadermatol.2024.0785 -
Skin Research and Technology : Official... May 2024Dermatomyositis (DM) is a rare inflammatory disease. Our research focuses on predicting poor prognosis in DM patients and evaluating the prognostic significance of...
BACKGROUND
Dermatomyositis (DM) is a rare inflammatory disease. Our research focuses on predicting poor prognosis in DM patients and evaluating the prognostic significance of ferritin and Salivary Sugar Chain Antigen-6 (KL-6) through multivariate logistic regression analysis.
METHODS
Between February 2018 and April 2020, 80 DM patients at our hospital were categorized into MDA5 positive (n = 20) and negative (n = 60) groups. We conducted multivariate logistic regression to determine DM's poor prognosis risk factors and evaluate ferritin/KL-6's predictive value for prognosis.
RESULTS
Analysis showed no gender, age, body mass index (BMI), or lifestyle (smoking, drinking) differences, nor in dyspnea, muscle weakness, skin ulcers, and acetylcysteine treatment effects (p > 0.05). Significant differences emerged in arrhythmias, interstitial pneumonia, C-reactive protein, albumin, and lactate dehydrogenase levels (p < 0.05). Before treatment, differences were negligible (p > 0.05), but post-treatment, serum KL-6 and ferritin levels dropped. MDA5 positive patients had elevated serum KL-6 and ferritin levels than survivors (p < 0.05), with a strong correlation to DM. Combined diagnosis using serum KL-6 and ferritin for DM prognosis showed area under curves of 0.716 and 0.634, significantly outperforming single-index diagnoses with an area under curve (AUC) of 0.926 (p < 0.05).
CONCLUSION
Serum KL-6 and ferritin show marked abnormalities in DM, useful as indicators for evaluating polymyositis and DM conditions. However, the study's small sample size is a drawback. Expanding the sample size is essential to monitor serum KL-6 and ferritin changes in DM patients under treatment more closely, aiming to improve clinical assessment and facilitate detailed research.
Topics: Adult; Aged; Female; Humans; Male; Middle Aged; Biomarkers; Dermatomyositis; Ferritins; Interferon-Induced Helicase, IFIH1; Logistic Models; Mucin-1; Multivariate Analysis; Predictive Value of Tests; Prognosis; Risk Factors
PubMed: 38682785
DOI: 10.1111/srt.13701 -
Current Rheumatology Reviews Apr 2024Mixed Connective Tissue Disease (MCTD) is a rare condition in children, characterized by a high titer of anti-ribonucleoprotein-U1 (anti-U1 RNP) antibodies, often...
BACKGROUND
Mixed Connective Tissue Disease (MCTD) is a rare condition in children, characterized by a high titer of anti-ribonucleoprotein-U1 (anti-U1 RNP) antibodies, often presenting with overlapping features of two or more rheumatologic disorders, including juvenile idiopathic arthritis (JIA), systemic lupus erythematous (SLE), systemic sclerosis (SSc), and juvenile dermatomyositis/polymyositis (JDM/PM).
CASE PRESENTATION
We report the case of an 8-year-old girl with a history of fever, hair loss, lower extremities edema, weakness, oral aphthous ulcers, and a high titer of anti-U1 RNP antibodies, which is consistent with the diagnosis of MCTD. The patient received immunomodulator drugs, and her disease went into remission.
CONCLUSION
Diagnosing MCTD in pediatric patients can be challenging. It should be considered especially in cases with recurrent muscular weakness or pain, lupus-like manifestations, and edema. Moreover, serum anti-U1 RNP testing can be a helpful diagnostic tool.
PubMed: 38676474
DOI: 10.2174/0115733971272403231221103006