Dermatomyositis developed in a recipient of allogeneic BMT; the differentiation of chronic GVHD and autoimmune disease

Steroid myopathy and rehabilitation in patients with cancer

Steroids are broadly used in oncology, despite known adverse events such as glucocorticosteroid-induced myopathy (SM). To date there are no accepted guidelines on the diagnosis and treatment of SM. The purpose of this review is to provide up-to-date information regarding SM with emphasis on neuro-oncology and hematopoietic stem cell transplant patients, given they are at high risk of experiencing SM following routine treatment with steroids. Our work is a combination of a comprehensive narrative review regarding etiology, pathogenesis, incidence, clinical presentation and treatment options for SM and a scoping review on exercise therapy for SM. We have identified 24 in vivo studies of different exercise modalities in the settings of glucocorticosteroid treatment. Twenty of 24 studies demonstrated decreased muscle catabolism with exercise training. Both endurance and resistance exercises at mild to moderate intensity were beneficial. The value of high-intensity activities remains questionable as it may worsen muscle atrophy. Rehabilitation interventions, along with pharmacologic and dietary considerations, may be beneficial in preventing or reversing SM. Potential adverse events of some of these interventions and expected caveats in translating findings in preclinical models to human settings warrant caution and demand controlled clinical studies.

Rare forms of inflammatory myopathies - part I, generalized forms

INTRODUCTION

The idiopathic inflammatory myopathies traditionally comprise dermatomyositis, polymyositis, immune-mediated necrotizing myopathy, anti-synthetase syndrome, and inclusion body myositis. In this review, we aimed to cover the less common forms of generalized myositis.

AREAS COVERED

We identified rare forms of widespread myositis on the basis of list provided by the homepage of the Neuromuscular disease center of Washington University, USA and on the basis of the authors' knowledge. We searched PubMed® and EMBASE® for relevant articles on these forms with the aim of providing as much as possible information on their clinical manifestations as well as guidance on their work-up and treatment.

EXPERT OPINION

There is substantial heterogeneity among the various rare forms of generalized myositis in terms of their frequency and characterization. Some forms are reasonably well defined, while others may not represent truly well-defined diseases, but rather variants of other myopathies. The landscape of rare forms appears to have evolved over time, with some forms now being better characterized, while others, such as SARS-Cov-2- and immune checkpoint inhibitor-related myositis have come to the fore only in recent years. Knowledge about rare forms of myositis can aid in their recognition and treatment.

Clinically amyopathic dermatomyositis manifested after the allogeneic haematopoietic stem cell transplantation: Case presentation and literature review

Clinically amyopathic dermatomyositis (CADM) lacks muscle symptoms, associated with rapidly progressive interstitial lung disease. Anti-melanoma differentiation-associated gene 5 (MDA-5) antibody has been identified as a disease-labelling autoantibody. We report two cases of CADM manifested after the allogeneic haematopoietic stem cell transplantation (allo-HSCT)-Case 1: a 56-year-old man with acute leukaemia received the allo-HSCT and Case 2: a 45-year-old female patient with lymphoma received the allo-HSCT. She received donor lymphocyte infusion because of a post-transplant relapse. After allo-HSCT or donor lymphocyte infusion, Gottron papules emerged, and both patients were diagnosed as CADM based on dermatological findings coupled with the positivity of anti-MDA-5 antibody, accompanied by interstitial shadows consistent with ILD on chest computed tomography. Case 2 was initially diagnosed as a kind of chronic graft versus host disease. Their symptoms were improved by the combination of immunosuppressive agents with a concomitant decrease in anti-MDA-5 antibody levels. For Case 2, rituximab was subsequently started for relapse of lymphoma, resulting in a substantial decrease in the level of anti-MDA-5 antibody and improvement in rash and ILD. Our cases raise a possibility that CADM emerges after the HSCT, highlighting the importance of early diagnosis to avoid fated progression into ILD.

Clinical Characteristics of Myositis Associated with Graft-Versus-Host Disease

PURPOSE OF REVIEW

Recipients of allogeneic hematopoietic stem cell transplantation (HSCT) are at increased risk for inflammatory myositis; histological subsets reported include dermatomyositis, necrotising myopathy and chronic graft-versus-host disease (cGVHD)-related myositis. Though corticosteroids and various immunosuppressive therapies have been used, there is a lack of consensus guidelines dictating therapy.

RECENT FINDINGS

Recent evidence suggests the fascia as a preferential target in cGVHD myositis, with conditioning regimens promoting fascial microtrauma. Positron emission tomography (PET) can be a useful diagnostic tool, and case reports suggest that the Bruton's tyrosine kinase inhibitor ibrutinib may have therapeutic potential. Emerging therapies include targeted B cell depletion with rituximab, and extracorporeal photophoresis. Clinicians need to be vigilant for the development of inflammatory myositis post-allogeneic HSCT as most patients respond to treatment. Advances in immunohistochemistry to determine the dominant cell type and cytokine profile may enable targeted and individualised therapies.

Juvenile Dermatomyositis: New Clues to Diagnosis and Therapy

PURPOSE OF REVIEW

To identify clues to disease activity and discuss therapy options.

RECENT FINDINGS

The diagnostic evaluation includes documenting symmetrical proximal muscle damage by exam and MRI, as well as elevated muscle enzymes-aldolase, creatine phosphokinase, LDH, and SGOT-which often normalize with a longer duration of untreated disease. Ultrasound identifies persistent, occult muscle inflammation. The myositis-specific antibodies (MSA) and myositis-associated antibodies (MAA) are associated with specific disease course variations. Anti-NXP-2 is found in younger children and is associated with calcinosis; anti-TIF-1γ+ juvenile dermatomyositis has a longer disease course. The diagnostic rash-involving the eyelids, hands, knees, face, and upper chest-is the most persistent symptom and is associated with microvascular compromise, reflected by loss of nailfold (periungual) end row capillaries. This loss is associated with decreased bioavailability of oral prednisone; the bioavailability of other orally administered medications should also be considered. At diagnosis, at least 3 days of intravenous methyl prednisolone may help control the HLA-restricted and type 1/2 interferon-driven inflammatory process. The requirement for avoidance of ultraviolet light exposure mandates vitamin D supplementation.

SUMMARY

This often chronic illness targets the cardiovascular system; mortality has decreased from 30 to 1-2% with corticosteroids. New serological biomarkers indicate occult inflammation: ↑CXCL-10 predicts a longer disease course. Some biologic therapies appear promising.

A case report and literature review of chronic graft-versus-host disease manifesting as polymyositis

Polymyositis (PM) is a rare but documented manifestation of chronic graft-versus-host disease (cGvHD) post allogeneic hematopoietic cell transplantation (HCT). We present the case of a 70-year-old male patient who developed severe cGvHD-related PM 3 years after undergoing allogeneic HCT for acute myeloid leukemia. The patient responded to steroids and was maintained long-term with hydroxychloroquine as a steroid-sparing agent. We review the literature concerning the diagnosis and treatment of PM as cGvHD as well as the differentiation of this manifestation from other forms of PM.

Proteasome immunosubunits protect against the development of CD8 T cell-mediated autoimmune diseases

Exposure of cells to inflammatory cytokines induces the expression of three proteasome immunosubunits, two of which are encoded in the MHC class II region. The induced subunits replace their constitutive homologs in newly formed "so-called" immunoproteasomes. Immunosubunit incorporation enhances the proteasome's proteolytic activity and modifies the proteasome's cleavage-site preferences, which improves the generation of many MHC class I-presented peptides and shapes the fine specificity of pathogen-specific CD8 T cell responses. In this article, we report on a second effect of immunoproteasome formation on CD8 T cell responses. We show that mice deficient for the immunosubunits β5i/low molecular mass polypeptide (LMP7) and β2i/multicatalytic endopeptidase complex-like-1 develop early-stage multiorgan autoimmunity following irradiation and bone marrow transplantation. Disease symptoms are caused by CD8 T cells and are transferable into immunosubunit-deficient, RAG1-deficient mice. Moreover, using the human Type 1 Diabetes Genetics Consortium MHC dataset, we identified two single nucleotide polymorphisms within the β5i/LMP7-encoding gene sequences, which were in strong linkage disequilibrium, as independent genetic risk factors for type 1 diabetes development in humans. Strikingly, these single nucleotide polymorphisms significantly enhanced the risk conferred by HLA haplotypes that were previously shown to predispose for type 1 diabetes. These data suggested that inflammation-induced immunosubunit expression in peripheral tissues constitutes a mechanism that prevents the development of CD8 T cell-mediated autoimmune diseases.