Update on dermatomyositis

Altered expression of human myxovirus resistance protein A in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder. The etiology of sporadic ALS (sALS) has not yet been clarified. An increasing body of evidence suggests the involvement of viral infections and interferons (IFNs). Human myxovirus resistance protein A (MxA) is an IFN-induced dynamin-like GTPase that acts as a potent antiviral factor. This study examined MxA expression in ALS patient spinal cords using immunohistochemistry. Thirty-two cases of sALS (pathologically proven ALS-TDP), 10 non-ALS, other neurological disease control cases were examined. In most ALS cases, MxA cytoplasmic condensates were observed in the remaining spinal anterior horn neurons. The ALS group had a significantly higher rate of MxA-highly expressing neurons than the non-ALS group. Colocalization of MxA cytoplasmic condensate and transactive response DNA-binding protein 43 kDa (TDP-43)-positive inclusions was rarely observed. Because MxA has antiviral activity induced by IFNs, our results suggest that IFNs are involved in the pathogenesis of ALS in spinal cord anterior horn neurons. Our study also suggests that monitoring viral infections and IFN activation in patients with ALS may be critically important.

TIF1-γ Positive Dermatomyositis with Spontaneous Muscular Hematoma in the Context of Ovarian Cancer: A Novel Survival Case Report

Background

Dermatomyositis (DM) represents a group of inflammatory myopathies, with TIF1-γ positive DM strongly associated with malignancies. Spontaneous muscular hematoma in DM patients is exceedingly rare and often prognosticates a severe clinical outcome, especially in the context of concurrent malignancy.

Case Presentation

We describe a novel survival case of a patient with TIF1-γ positive DM and an underlying ovarian tumor who developed a spontaneous muscular hematoma. Despite the traditionally poor prognosis of these conditions, the patient survived through a comprehensive treatment regimen. This included targeted chemotherapy for ovarian cancer (Carboplatin and Paclitaxel), alongside corticosteroids, immunoglobulins, and immunosuppressants for DM, as well as component blood transfusions, coagulation correction therapy to control hematoma, and integrated management: nutritional support, lung function exercise, volume management.

Results

The integrated treatment strategy stabilized the patient's condition and resolved the hematoma, a significant achievement given the usual high mortality rate of such complications.

Conclusion

This case underscores the importance of a multidisciplinary approach in the early diagnosis and treatment of TIF1-γ positive DM with complex comorbidities, including spontaneous muscular hematoma and ovarian cancer. It highlights the potential for favorable outcomes with aggressive and coordinated treatment strategies.

The Clinical Value of the Neutrophil-to-Lymphocyte Ratio, the C-Reactive Protein-to-Albumin Ratio, the Systemic Inflammatory Index, and the Systemic Inflammatory Response Index in Patients with the Anti-Synthetase Syndrome

Objective

There are no studies examining the role of the neutrophil-to-lymphocyte ratio (NLR), the C-reactive protein-to-albumin ratio (CAR), the systemic inflammatory index (SII), and the systemic inflammatory response index (SIRI) in anti-synthetase syndrome (ASS). We aim to compare NLR, CAR, SII, and SIRI in ASS and dermatomyositis/polymyositis (DM/PM), as well as to examine potential correlations between NLR, CAR, SII, and SIRI and clinical features and laboratory parameters in ASS.

Methods

Retrospective collection of data from 111 patients with ASS and 175 patients with DM/PM. A Spearman rank correlation analysis was utilized to analyze the correlation between NLR, CAR, SII, and SIRI and inflammatory indexes. Receiver operating characteristic (ROC) curves were used to assess the diagnostic value. Univariate logistic regression analysis was performed to assess risk factors for interstitial lung disease (ILD).

Results

Compared with DM/PM, NLR, CAR, SII, and SIRI were significantly greater in ASS patients (p < 0.05). NLR, CAR, SII, and SIRI were correlated with albumin, lactic dehydrogenase (LDH), C-reactive protein (CRP), ferritin, white blood cell (WBC), platelets, and myositis disease activity assessment visual analog scales (MYOACT) score (p < 0.05). The ROC curves analysis showed that NLR, SII, and SIRI were all highly predictive of the occurrence of ASS. Comparisons based on clinical characteristics showed elevated levels of NLR, CAR, SII, and SIRI in ASS patients with ILD, fever, and infection (p < 0.05). Univariate logistic regression analysis revealed that NLR, CAR, and SII were significant risk factors for ASS-ILD (p < 0.05).

Conclusion

The levels of NLR, CAR, SII, and SIRI were higher in ASS than in DM/PM and correlated with disease activity and specific clinical features. NLR, CAR, SII, and SIRI may be an aid in differentiating ASS from DM/PM and maybe promising biomarkers for ASS.

Diagnosis of Thyroid Neoplasm-Associated Dermatomyositis in Ethiopian Woman

Background

Dermatomyositis is an inflammatory myopathies causing proximal muscle weakness accompanied by muscular inflammation and skin rash. Dermatomyositis patients have a higher incidence of malignancy as compared to the general population.

Case Report

A 52-year-old known female patient with a toxic multi-nodular goiter presented with insidious onset of itchy erythematous rash on her neck and bilateral hands and progressive muscle weakness of 4 months' duration. Associated with this, she had photosensitivity, and periorbital edema of 2 months' duration. On physical examination, she had an anterior neck mass, proximal muscle weakness, periorbital edema, and violaceous skin rash on her bilateral arms, shoulders and neck. Thyroid function tests were normal, creatinine kinase was elevated, and muscle biopsy revealed inflammatory myositis. Ultrasound of the anterior neck mass and analysis of fine needle aspiration suggested thyroid cancer.

Conclusion

A high index of clinical suspicion is usually required for early diagnosis of dermatomyositis in resource-limited settings in order to prevent adverse outcomes and identify associated malignancies.

Complement and MHC patterns can provide the diagnostic framework for inflammatory neuromuscular diseases

Histopathological analysis stands as the gold standard for the identification and differentiation of inflammatory neuromuscular diseases. These disorders continue to constitute a diagnostic challenge due to their clinical heterogeneity, rarity and overlapping features. To establish standardized protocols for the diagnosis of inflammatory neuromuscular diseases, the development of cost-effective and widely applicable tools is crucial, especially in settings constrained by limited resources. The focus of this review is to emphasize the diagnostic value of major histocompatibility complex (MHC) and complement patterns in the immunohistochemical analysis of these diseases. We explore the immunological background of MHC and complement signatures that characterize inflammatory features, with a specific focus on idiopathic inflammatory myopathies. With this approach, we aim to provide a diagnostic algorithm that may improve and simplify the diagnostic workup based on a limited panel of stainings. Our approach acknowledges the current limitations in the field of inflammatory neuromuscular diseases, particularly the scarcity of large-scale, prospective studies that validate the diagnostic potential of these markers. Further efforts are needed to establish a consensus on the diagnostic protocol to effectively distinguish these diseases.

Contribution of Complement, Microangiopathy and Inflammation in Idiopathic Inflammatory Myopathies

PURPOSE OF REVIEW

Idiopathic inflammatory myopathies (IIMs) are a heterogeneous group characterized by muscle weakness and skin symptoms and are categorized into six subtypes: dermatomyositis (DM), polymyositis (PM), anti-synthetase syndrome (ASS), immune-mediated myopathy (IMNM), inclusion body myopathy (IBM), and overlap myositis. Myositis-specific autoantibodies were detected for the diagnosis and classification of IIM. This review highlights the pathogenic contributions of the complement system, microangiopathy, and inflammation in IIM.

RECENT FINDINGS

Deposition of complement around capillaries and/or the sarcolemma was observed in muscle biopsy specimens from patients with DM, ASS, and IMNM, suggesting the pathomechanism of complement-dependent muscle and endothelial cell injury. A recent study using human muscle microvascular endothelial cells showed that Jo-1 antibodies from ASS induce complement-dependent cellular cytotoxicity in vitro. Based on both clinical and pathological observations, antibody- and complement-mediated microangiopathy may contribute to the development of DM and anti-Jo-1 ASS. Juvenile DM is characterized by the loss of capillaries, perivascular inflammation, and small-vessel angiopathies, which may be related to microinfarction and perifascicular atrophy. Several serum biomarkers that reflect the IFN1 signature and microangiopathy are elevated in patients with DM. The pathological observation of myxovirus resistance protein A (MxA), which suggests a type 1 interferon (IFN1) signature in DM, supports the diagnosis and further understanding of the pathomechanism of IIM. A recent report showed that an increase in triggering receptor expressed on myeloid cells (TREM-1) around perimysial blood vessels and muscles in patients with IIM plays a role in triggering inflammation and promoting the migration of inflammatory cells by secreting proinflammatory cytokines, such as tumor necrosis factor α.

SUMMARY

The deposition of complement in muscles and capillaries is a characteristic feature of DM, ASS, and IMNM. Microangiopathy plays a pathogenic role in DM, possibly resulting in perifascicular atrophy. Further understanding of the detailed pathomechanism regarding complement, microangiopathy, and inflammation may lead to novel therapeutic approaches for IIM.

Clinical features of dermatomyositis patients with anti-TIF1 antibodies: A case based comprehensive review

BACKGROUND AND OBJECTIVES

Dermatomyositis is chronic autoimmune disease primarily affecting skin and muscles. Antibodies are key players of pathogenesis and are in strong correlation with distinct clinical phenotypes. We present a case and a comprehensive review of the literature on dermatomyositis patients with Anti TIF1 antibodies.

METHODS

PubMed and Web of Science databases were reviewed. 166 articles were identified; 95 of them were evaluated; 79 of them included to the study. 45 of the included articles were case reports 9 were case series and 25 were research articles. In total 1065 patients were identified but number of patients with available information for different clinical features varied.

RESULTS

69.6% of the patients with Anti TIF1-γ were female. Prevalence of malignancy was 42.6% among patients with Anti TIF1-γ. Muscle weakness (83%), Gottron sign (82.2%), heliotrope rash (73.7%), nailfold capillary changes (67.7%), dysphagia (38.4%), and joint involvement (31.1%) were the most common clinical features seen in patients with Anti TIF1-γ. Interstitial lung disease (ILD) was reported among 8.7% of patients with Anti TIF1-γ. Advanced age, male gender, dysphagia, and V-neck rash were significant risk factors for malignancy, whereas juvenile age, ILD, TIF1-β antibodies and joint involvement were associated with a decreased risk for malignancy. Advanced age, malignancy, dysphagia, and muscle involvement were associated with an increased risk for mortality.

CONCLUSIONS

Patients with advanced age, male gender, dysphagia, and V-neck rash require strict cancer screening. Patients with advanced age, malignancy, dysphagia, and muscle involvement have poor prognosis and should receive aggressive treatment.

[Two cases of anti-nuclear matrix protein 2 antibody-positive dermatomyositis sine dermatitis with severe diffuse subcutaneous edema and dysphagia]

Case 1 involved a 68-year-old woman who was admitted to our hospital because of muscle weakness, diffuse subcutaneous edema, dysphagia, and an elevated serum creatine kinase level that had worsened within the previous month. Case 2 involved a 78-year-old woman who was admitted to our hospital because of muscle weakness, bilateral shoulder pain, diffuse subcutaneous edema, and dysphagia that had gradually worsened during the past 5 months. Both patients showed severe diffuse subcutaneous edema and dysphagia and underwent enteral tube feeding. Although they had no skin lesions consistent with dermatomyositis, muscle biopsies showed myxovirus resistance protein A (MxA) expansion, and blood tests showed positivity for anti-nuclear matrix protein 2 (anti-NXP-2) antibody. Therefore, both presents were diagnosed with anti-NXP-2 antibody-positive dermatomyositis sine dermatitis (DMSD). Anti-NXP-2 antibody-positive dermatomyositis has been reported to be closely associated with DMSD, severe edema and dysphagia. Differential diagnosis for patients who develop myositis with severe subcutaneous edema and dysphagia should include anti-NXP-2 antibody-positive dermatomyositis, and it is important to consider measurement of anti-NXP-2 antibody.

Cancer and Myotonic Dystrophy

Myotonic dystrophy (DM) is the most common muscular dystrophy in adults. Dominantly inherited CTG and CCTG repeat expansions in DMPK and CNBP genes cause DM type 1 (DM1) and 2 (DM2), respectively. These genetic defects lead to the abnormal splicing of different mRNA transcripts, which are thought to be responsible for the multiorgan involvement of these diseases. In ours and others' experience, cancer frequency in patients with DM appears to be higher than in the general population or non-DM muscular dystrophy cohorts. There are no specific guidelines regarding malignancy screening in these patients, and the general consensus is that they should undergo the same cancer screening as the general population. Here, we review the main studies that investigated cancer risk (and cancer type) in DM cohorts and those that researched potential molecular mechanisms accounting for DM carcinogenesis. We propose some evaluations to be considered as malignancy screening in patients with DM, and we discuss DM susceptibility to general anesthesia and sedatives, which are often needed for the management of cancer. This review underscores the importance of monitoring the adherence of patients with DM to malignancy screenings and the need to design studies that determine whether they would benefit from a more intensified cancer screening than the general population.