Therapeutic targets in patients with inflammatory myopathies: present approaches and a look to the future

Orbital myositis as an initial manifestation of Behcet's disease

Purpose

We report the case of a 32-year-old woman with orbital myositis prior to onset of Behcet's disease (BD).

Observations

A 32-year-old woman was referred to our hospital for a complaint of right eyelid swelling, eye pain, and diplopia. Her best-corrected visual acuity was 20/32 on the right, and 20/16 on the left. She was diagnosed as idiopathic orbital inflammation, and received two pulses of intravenous administration of methylprednisolone, followed by oral prednisolone. Three months later, she developed bilateral orbital myositis, and received one more pulse therapy, followed by oral prednisolone and cyclosporin. About one year after the first visit, oral aphthae, genital ulcers, and folliculitis-like skin rash appeared, and the physician diagnosed incomplete type BD. The patient had no uveitis during the disease course. Orbital inflammation and systemic manifestations of BD were ultimately well controlled with small doses of prednisolone.

Conclusion and importance

BD may develop during the course of orbital inflammation.

The anti-inflammatory effect of myrrh ethanolic extract in comparison with prednisolone on an autoimmune disease rat model induced by silicate

Autoimmune disease is a complex chronic disease that triggers immune activation against autoantigens resulting in tissue damage. Epidemiological data showed that autoimmune diseases are increasing worldwide over the last decades owing to increased environmental pollution. This study investigates the therapeutic effect of myrrh as a natural medicine compared to prednisolone in the treatment of immune-mediated glomerulonephritis induced by silicate. The autoimmune disease model in rats was induced by injecting 5 mg crystalline sodium silicate suspension subcutaneously once weekly for 20 weeks, and then the rats were treated either with myrrh extract or prednisolone or with both for 6 weeks. Liver and kidney function tests, histopathology, and immunohistochemistry of TNF-α expression in kidney tissue were performed. The creatinine significantly elevated in silica-treated group and decreased in other treated groups. Histopathology of the kidney revealed improvement of glomerular and tubular basement thickness in all treated groups, but the inflammatory cell count slightly decreased in the group treated with myrrh than the other treated groups which showed a marked decrease. TNF-α expression was significantly decreased in all treated groups. Interestingly, the myrrh did not produce hepatic lesions and improve the side effect of prednisolone in the liver when taken in combination. Therefore, myrrh extract possessed anti-inflammatory properties and counteracted the side effect of prednisolone on the liver. Myrrh extract can serve as a conjunctive therapy with prednisolone to treat autoimmune diseases.

Complement in autoimmune inflammatory myopathies, the role of myositis-associated antibodies, COVID-19 associations, and muscle amyloid deposits

INTRODUCTION

The inflammatory myopathies (IM) have now evolved into distinct subsets requiring clarification about their immunopathogenesis to guide applications of targeted therapies.

AREAS COVERED

Immunohistopathologic criteria of IM with a focus on complement, anti-complement therapeutics, and other biologic immunotherapies. The COVID19-triggered muscle autoimmunity along with the correct interpretation of muscle amyloid deposits is discussed.

EXPERT OPINION

The IM, unjustifiably referred as idiopathic, comprise Dermatomyositis (DM), Necrotizing Autoimmune Myositis (NAM), Anti-synthetase syndrome-overlap myositis (Anti-SS-OM), and Inclusion-Body-Myositis (IBM). In DM, complement activation with MAC-mediated endomysial microvascular destruction and perifascicular atrophy is the fundamental process, while innate immunity activation factors, INF1 and MxA, sense and secondarily enhance inflammation. Complement participates in muscle fiber necrosis from any cause and may facilitate muscle-fiber necrosis in NAM but seems unlikely that myositis-associated antibodies participate in complement-fixing. Accordingly, anti-complement therapeutics should be prioritized for DM. SARS-CoV-2 can potentially trigger muscle autoimmunity, but systematic studies are needed as the reported autopsy findings are not clinically relevant. In IBM, tiny amyloid deposits within muscle fibers are enhanced by inflammatory mediators contributing to myodegeneration; in contrast, spotty amyloid deposits in the endomysial connective tissue do not represent 'amyloid myopathy' but only have diagnostic value for amyloidosis due to any cause.

Microsporidia infection in patients with autoimmune diseases

Purpose

Microsporidium is a spore-forming intracellular parasite that affects a wide range of hosts including humans. The tumor necrosis factor alpha (TNF-α) plays a key role in the immunity to infection with microsporidia. Recently, the TNF-α antagonists have proven successful in treating variable autoimmune diseases. In the current study, we aimed to investigate the impact of using TNF-α antagonists as a therapeutic regimen in the prevalence of infections with microsporidia.

Materials and Methods

Diarrheal patients with distinct autoimmune diseases (n = 100) were assigned to the study. Patients taking anti-TNF-α medications (n = 60) were allocated to Group 1A and those undergoing non-TNF-α inhibitor treatment (n = 40) to Group 1B. Furthermore, patients with diarrhea without autoimmune disorders (n = 20) were allocated as controls. Stool specimens, 3 per patient, were collected and microscopically examined for microsporidia spores. A microsporidia-specific stool polymerase chain reaction was used to confirm the microscopic findings.

Results

Microsporidia infection was identified in 28.3% (17/60), 10% (4/40), and in 5% (1/20) of patients in Group 1A, Group 1B, and in the control group, respectively. Overall, infection was significantly high in cases compared to the controls and in patients receiving TNF-α antagonists compared to patients not given TNF-α inhibitors (P < 0.05). Finally, infection was significantly higher in cases treated with TNF-α antagonists for ≥2 months compared to cases treated for <2 months of duration (P < 0.05).

Conclusion

There was a significant increase in microsporidia infection in autoimmune disease patients undergoing treatment with TNF-α antagonists, and the duration of treatment is one of the risk factors. The study highlights the importance of microsporidia testing in immunocompromised patients, particularly those undergoing treatment with anti-TNF-α drugs and emphasises the need for awareness among clinicians regarding this opportunistic parasite.

Biologics in refractory myositis: experience in juvenile vs. adult myositis; part II: emerging biologic and other therapies on the horizon

The idiopathic inflammatory myopathies (IIM) until recently have been considered a heterogeneous broad group of six autoimmune muscle diseases. Initially, autoantibodies in IIM (including JDM) and CD8+ T cell-induced cytotoxicity (PM and IBM) were the predominant recognized etiopathology mechanisms used to classify myopathies. In the early late 1990's to 2000's, evolving understanding of the molecules such as interleukin (IL), tumor necrosis factor (TNF), interferon (IFN), and other cytokines as well as differences in response to therapies, has led IIM researchers to look beyond previous disease mechanisms. For decades the overexpression of Th1- associated cytokines (TNF-α, IFN-γ and IL-12) in the areas of inflammation in skin and muscle in IIM pointed to Th1 as the primary pathway for inflammation in myositis.However, in the last decade overexpression and elevated level of Th17-associated cytokines (IL-17, IL-22, and IL-6) were identified in the blood and the inflamed muscles of myositis patients. We also do not know how Th1 and Th2 cytokines work differently in diverse hosts, in different concentrations, in different inflammatory milieus, and in the presence or absence of each other or other adhesion/co-stimulatory molecules such as NF-κB. Also, several autoantibodies to intracellular organelles have been identified in myositis.In this review, we will discuss the most recent advances in IIM research and how that might bring new biologic therapies to market in the next 5-15 years to assist in the care of our most difficult IIM and JDM patients.

Immunotherapies for Immune-Mediated Myopathies: A Current Perspective

Until recently, the treatment of immune-mediated inflammatory myopathies has largely been empirical with glucocorticoids, steroid-sparing immunosuppressive drugs, and intravenous immunoglobulin. However, a proportion of patients are only partially responsive to these therapies, and there has been a need to consider alternative treatment approaches. In particular, patients with inclusion body myositis are resistant to conventional immunotherapies or show only a transient response, and remain a major challenge. With increasing recognition of the different subtypes of immune-mediated inflammatory myopathies, and improved understanding of their pathogenesis, more targeted treatments are now being trialled. The overall approach to treatment, and novel therapies targeting B cells, T cells, and specific cytokines are discussed in this review.

"Orbiting around" the orbital myositis: clinical features, differential diagnosis and therapy

Orbital myositis (OM) is a rare disease whose clinical heterogeneity and different treatment options represent a diagnostic and therapeutic challenge. We aim to review the state of knowledge on OM, also describing a cohort of patients diagnosed in our centre, to highlight some remarkable clinical features. A literature review was conducted in PubMed and Medline databases. The herein described cohort is composed of seven OM patients, diagnosed according to clinical, laboratory and neuroradiological features, whose clinical data were retrospectively analysed. OM is a non-infectious, inflammatory process primarily involving extraocular eye-muscles. It typically presents as an acute to sub-acute, painful ophthalmoplegia with signs of ocular inflammation, but atypical cases without pain or with a chronic progression have been described. The wide range of OM mimicking diseases make a prompt diagnosis challenging but orbit MRI provides valuable clues for differential diagnosis. Timely treatment is greatly important as OM promptly responds to steroids; nevertheless, partial recovery or relapses often occur. In refractory, recurrent or steroid-intolerant cases other therapeutic options (radiotherapy, immunosuppressants, immunoglobulins) can be adopted, but the most effective therapeutic management is yet to be established. In this review, we provide a detailed clinical description of OM, considering the main differential diagnoses and suggesting the most useful investigations. In light of the currently available data on therapy efficacy, we propose a therapeutic algorithm that may guide neurologists in OM patients' management.

Cost-utility analysis of intravenous immunoglobulin for the treatment of steroid-refractory dermatomyositis in Thailand

INTRODUCTION

Intravenous immunoglobulin (IVIG) has been shown to be effective in treating steroid-refractory dermatomyositis (DM). There remains no evidence of its cost-effectiveness in Thailand.

OBJECTIVE

Our objective was to estimate the cost utility of IVIG as a second-line therapy in steroid-refractory DM in Thailand.

METHODS

A Markov model was developed to estimate the relevant costs and health benefits for IVIG plus corticosteroids in comparison with immunosuppressant plus corticosteroids in steroid-refractory DM from a societal perspective over a patient's lifetime. The effectiveness and utility parameters were obtained from clinical literature, meta-analyses, medical record reviews, and patient interviews, whereas cost data were obtained from an electronic hospital database and patient interviews. Costs are presented in $US, year 2012 values. All future costs and outcomes were discounted at a rate of 3% per annum. One-way and probabilistic sensitivity analyses were also performed.

RESULTS

Over a lifetime horizon, the model estimated treatment under IVIG plus corticosteroids to be cost saving compared with immunosuppressant plus corticosteroids, where the saving of costs and incremental quality-adjusted life-years (QALYs) were $US4738.92 and 1.96 QALYs, respectively. Sensitivity analyses revealed that probability of response of immunosuppressant plus corticosteroids was the most influential parameter on incremental QALYs and costs. At a societal willingness-to-pay threshold in Thailand of $US5148 per QALY gained, the probability of IVIG being cost effective was 97.6%.

CONCLUSIONS

The use of IVIG plus corticosteroids is cost saving compared with treatment with immunosuppressant plus corticosteroids in Thai patients with steroid-refractory DM. Policy makers should consider using our findings in their decision-making process for adding IVIG to corticosteroids as the second-line therapy for steroid-refractory DM patients.

Cytokines in immune-mediated inflammatory myopathies: cellular sources, multiple actions and therapeutic implications

The idiopathic inflammatory myopathies are a heterogeneous group of disorders characterised by diffuse muscle weakness and inflammation. A common immunopathogenic mechanism is the cytokine-driven infiltration of immune cells into the muscle tissue. Recent studies have further dissected the inflammatory cell types and associated cytokines involved in the immune-mediated myopathies and other chronic inflammatory and autoimmune disorders. In this review we outline the current knowledge of cytokine expression profiles and cellular sources in the major forms of inflammatory myopathy and detail the known mechanistic functions of these cytokines in the context of inflammatory myositis. Furthermore, we discuss how the application of this knowledge may lead to new therapeutic strategies for the treatment of the inflammatory myopathies, in particular for cases resistant to conventional forms of therapy.

Ocular myositis

Ocular myositis frequently manifests with orbital pain and diplopia. The diagnosis of ocular myositis falls within the overall classification of idiopathic orbital inflammatory diseases, defined as non-infective non-specific orbital inflammation without identifiable local or systemic causes. Orbital myositis may form part of more widespread systemic inflammatory processes such as Crohn's disease and the more recently described IgG4-related disease. There is also a broad range of ophthalmic differential diagnoses. Diagnosis, assessment and management of ocular myositis requires the cooperation of ophthalmologists and rheumatologists/immunologists in order to achieve the best patient outcomes. The current literature and avenues of future research are reviewed.

The treatment strategies of autoimmune disease may need a different approach from conventional protocol: a review

Autoimmune disease (AD) is one of the emerging noncommunicable diseases. Remission is a possibility in AD, but current treatment strategies are not able to achieve this. We have well-established protocols for infections, oncology, metabolic diseases, and transplantation which are often used as models for the management of AD. Studies and observations suggest that in contrast to diseases used as a role model, AD has wide variability, different causative and pathogenic process, which is highly dynamic, making the current treatment strategies to fall short of expected complete remission. In this brief review, it is attempted to highlight the current understanding of AD and the probable gaps in the treatment strategies. Few hypothetical suggestions to modify the treatment protocols are presented.

Novel future therapeutic options in myasthenia gravis

BACKGROUND

Myasthenia Gravis (MG) is an autoimmune disease caused by complement-fixing antibodies against the acetylcholine receptors (AChR). Antigen-specific CD4+ T cells, Tregs and Th17+ are also necessary. Consequently, antibodies, B cells, molecules associated with signalling pathways on T helper cells, cytokines and complement are targets for more specific treatment options.

OBJECTIVES

Because available immunosuppressive therapies cause unacceptable side effects after long-term use or are not always effective in inducing remission, novel biological agents directed against the following targets might be options for future therapies in MG: 1) T cell Intracellular Signaling Pathways associated with T cell activation, such as monoclonal antibodies against CD52, Interleukin 2-receptor (IL-2 R), co-stimulatory molecules or compounds inhibiting Janus tyrosine kinases JAK1, JAK3; 2) B cells, against key B cell-surface molecules or trophic factors B cell activation factor (BAFF) and a proliferating inducing ligand (APRIL); 3) Complement, against C3 or C5 that intercept membranolytic attack complex formation; 4) Cytokines and cytokine receptors, including IL-6, IL-17, the p40 subunit of IL12/1L-23, and GM-CSF; and 5) Lymphocyte migration molecules. Construction of recombinant AChR antibodies that block the binding of the pathogenic antibodies, can be a future molecular tool.

CONCLUSION

New biological agents are in the offing for future therapies in MG. Their efficacy needs to be secured with vigorously controlled clinical trials and weighted against excessive cost and rare complications.

Inclusion body myositis: therapeutic approaches

The idiopathic inflammatory myopathies are a heterogeneous group of diseases that include dermatomyositis (DM), polymyositis (PM), inclusion body myositis (IBM) and other less common myopathies. These are clinically and histopathologically distinct diseases with many shared clinical features. IBM, the most commonly acquired inflammatory muscle disease occurs in individuals aged over 50 years, and is characterized by slowly progressive muscle weakness and atrophy affecting proximal and distal muscle groups, often asymmetrically. Unlike DM and PM, IBM is typically refractory to immunotherapy. Although corticosteroids have not been tested in randomized controlled trials, the general consensus is that they are not efficacious. There is some suggestion that intravenous immunoglobulin slows disease progression, but its long-term effectiveness is unclear. The evidence for other immunosuppressive therapies has been derived mainly from case reports and open studies and the results are discouraging. Only a few clinical trials have been conducted on IBM, making it difficult to provide clear recommendations for treatment. Moreover, IBM is a slowly progressive disease so assessment of treatment efficacy is problematic due to the longer-duration trials needed to determine treatment effects. Newer therapies may be promising, but further investigation to document efficacy would be expensive given the aforementioned need for longer trials. In this review, various treatments that have been employed in IBM will be discussed even though none of the interventions has sufficient evidence to support its routine use.

Inflammatory myopathies: management of steroid resistance

PURPOSE OF REVIEW

The inflammatory myopathies include polymyositis, dermatomyositis, necrotizing autoimmune myopathy (NAM), and inclusion body myositis (IBM). On the basis of clinical experience, most patients respond to corticosterioids to some degree or for a time period. For patients insufficiently responding or for steroid-sparing, the treatment options vary among practitioners, generating a genuine uncertainty. This timely review highlights emerging new therapies and provides practical therapeutic algorithms.

RECENT FINDINGS

For patients insufficiently responding to corticosteroids, the commonly used immunosuppressants, such as azathioprine, mycophenolate, methotrexate, or cyclosporine, may exert a nonevidence-based 'steroid-sparing' effect but provide minimal benefit on their own. The second line therapy is intravenous immunoglobulin (IVIg) based on a controlled study conducted in dermatomyositis; the drug is also effective in many patients with polymyositis and NAM. Rituximab and tacrolimus may offer additional benefit. Anti-TNF agents are disappointing. IBM remains difficult to treat; although early on some patients may partially respond to steroids or IVIg, they soon become unresponsive and the disease progresses. Emerging agents against T cells, B cells, and transmigration molecules are discussed as promising therapeutic options.

SUMMARY

New biological agents are in the offing for control trials. Appropriate outcome measures are however needed to assess and monitor responses.

Advances in the diagnosis, pathogenesis and treatment of CIDP

Chronic inflammatory demyelinating polyneuropathy (CIDP) is the most common chronic autoimmune neuropathy. Despite clinical challenges in diagnosis-owing in part to the existence of disease variants, and different views on how many electrophysiological abnormalities are needed to document demyelination-consensus criteria seem to have been reached for research or clinical practice. Current standard of care involves corticosteroids, intravenous immunoglobulin (IVIg) and/or plasmapheresis, which provide short-term benefits. Maintenance therapy with IVIg can induce sustained remission, increase quality of life and prevent further axonal loss, but caution is needed to avoid overtreatment. Commonly used immunosuppressive drugs offer minimal benefit, necessitating the development of new therapies for treatment-refractory patients. Advances in our understanding of the underlying immunopathology in CIDP have identified new targets for future therapeutic efforts, including T cells, B cells, and transmigration and transduction molecules. New biomarkers and scoring systems represent emerging tools with the potential to predict therapeutic responses and identify patients with active disease for enrollment into clinical trials. This Review highlights the recent advances in diagnosing CIDP, provides an update on the immunopathology including new target antigens, and discusses current treatments, ongoing challenges and future therapeutic directions.

Therapeutic advances and future prospects in immune-mediated inflammatory myopathies

THE INFLAMMATORY MYOPATHIES INCLUDE THREE DISTINCT ENTITIES: polymyositis (PM), dermatomyositis (DM), and inclusion body myositis (IBM). A T-cell-mediated cytotoxic process in PM and IBM and a complement-mediated microangiopathy in DM are the hallmarks of the underlying autoimmune processes. The most consistent therapeutic problem remains the distinction of PM from the difficult-to-treat mimics such as s-IBM, necrotizing myopathies and inflammatory dystrophies. This review provides a step-by-step approach to the treatment of inflammatory myopathies, highlights the common pitfalls and mistakes in therapy, and identifies the emerging new therapies. In uncontrolled studies, PM and DM respond to prednisone to some degree and for some period of time, while a combination with one immu-nosuppressive drug (azathioprine, cyclosporine, mycophenolate, methotrexate) offers additional benefit or steroid-sparing effect. In contrast, IBM is resistant to most of these therapies, most of the time. Controlled studies have shown that IVIg is effective and safe for the treatment of DM, where is used as a second, and at times first, line therapy. IVIg seems to be also effective in the majority of patients with PM based on uncontrolled series, but it offers transient help to a small number of patients with IBM especially those with dysphagia. Bona fide patients with PM and DM who become resistant to the aforementioned therapies, may respond to rituximab, tacrolimus or rarely to an tumor necrosis factor alpha inhibitor. For IBM patients, experience with alemtuzumab, a T-cell-depleting monoclonal antibody, is encouraging.

Pathophysiology of inflammatory and autoimmune myopathies

The main subtypes of inflammatory myopathies include dermatomyositis (DM), polymyositis (PM), necrotizing autoimmune myositis (NAM) and sporadic inclusion-body myositis (sIBM). The review provides an update on the main clinical characteristics unique to each subset, including fundamental aspects on muscle pathology helpful to assure accurate diagnosis, underlying immunopathomechanisms and therapeutic strategies. DM is a complement-mediated microangiopathy leading to destruction of capillaries, distal hypoperfusion and inflammatory cell stress on the perifascicular regions. NAM is an increasingly recognized subacute myopathy triggered by statins, viral infections, cancer or autoimmunity with macrophages as the final effector cells mediating fiber injury. PM and IBM are characterized by cytotoxic CD8-positive T cells which clonally expand in situ and invade MHC-I-expressing muscle fibers. In IBM, in addition to autoimmunity, there is vacuolization and intrafiber accumulation of degenerative and stressor molecules. Pro-inflammatory mediators, such as gamma interferon and interleukin IL1-β, seem to enhance the accumulation of stressor and amyloid-related misfolded proteins. Current therapies using various immunosuppressive and immunomodulating drugs are discussed for PM, DM and NAM, and the principles for effective treatment strategies in IBM are outlined.

FOXP3+ T regulatory cells in idiopathic inflammatory myopathies

FOXP3+ T regulatory cells (Tregs) are considered key players in the maintenance of immune homeostasis. Here we studied the presence and potential role of FOXP3+ Tregs in myositis. CD3 and FOXP3 expression in dermatomyositis, polymyositis and inclusion body myositis was assessed by immunohistochemistry and real-time PCR. FOXP3+ Tregs were found in close proximity to effector cells and their numbers correlated with the degree of inflammation. Despite divergent pathogenetic concepts, we observed no differences in the frequency of FOXP3 immunoreactive cells or FOXP3 mRNA expression between different myositis entities. Functional assays using human myoblasts as targets of CD8+ cells demonstrate that Tregs are capable to inhibit the lytic activity of cytotoxic cells. Our data suggest that FOXP3 Tregs serve to counterbalance muscle destruction by cytotoxic T cells in myositis.

Functions of Tat: the versatile protein of human immunodeficiency virus type 1

Human immunodeficiency virus type 1 (HIV-1) Tat is a multifunctional protein that contributes to several pathological symptoms of HIV-1 infection as well as playing a critical role in virus replication. Tat is a robust transactivating protein that induces a variety of effects by altering the expression levels of cellular and viral genes. The functions of Tat are therefore primarily related to its role in modulation of gene expression. In this review the functions of HIV-1 Tat that have been well documented, as well as a number of novel functions that have been proposed for this protein, are discussed. Since some of the functions of Tat vary in different cell types in a concentration-dependent manner and because Tat sometimes exerts the same activity through different pathways, study of this protein has at times yielded conflicting and controversial results. Due to its pivotal role in viral replication and in disease pathogenesis, Tat and the cellular pathways targeted by Tat are potential targets for new anti-HIV drugs.

How citation distortions create unfounded authority: analysis of a citation network

OBJECTIVE

To understand belief in a specific scientific claim by studying the pattern of citations among papers stating it.

DESIGN

A complete citation network was constructed from all PubMed indexed English literature papers addressing the belief that beta amyloid, a protein accumulated in the brain in Alzheimer's disease, is produced by and injures skeletal muscle of patients with inclusion body myositis. Social network theory and graph theory were used to analyse this network.

MAIN OUTCOME MEASURES

Citation bias, amplification, and invention, and their effects on determining authority.

RESULTS

The network contained 242 papers and 675 citations addressing the belief, with 220,553 citation paths supporting it. Unfounded authority was established by citation bias against papers that refuted or weakened the belief; amplification, the marked expansion of the belief system by papers presenting no data addressing it; and forms of invention such as the conversion of hypothesis into fact through citation alone. Extension of this network into text within grants funded by the National Institutes of Health and obtained through the Freedom of Information Act showed the same phenomena present and sometimes used to justify requests for funding.

CONCLUSION

Citation is both an impartial scholarly method and a powerful form of social communication. Through distortions in its social use that include bias, amplification, and invention, citation can be used to generate information cascades resulting in unfounded authority of claims. Construction and analysis of a claim specific citation network may clarify the nature of a published belief system and expose distorted methods of social citation.

Inclusion body myositis pathomechanism and therapy

Az inclusiós testes myositis az idiopathiás inflammatorikus myopathiák vakuólaképződéssel járó formái közé tartozik, azok 15–28%-át képezi. Fontos a korai felismerés, mert alattomosan progrediáló betegségről van szó, és a már kialakult izomatrófia nehezen kezelhető. Ötven év felett a leggyakoribb krónikus progresszív izombetegség. Patomechanizmusában egyrészt degeneratív folyamatok, a béta-amyloid-lerakódás játszik szerepet, másrészt a polymyositishez hasonlóan autoinvazív klonális CD8+-T-lymphocyták által mediált celluláris citotoxicitás. A két eltérő patomechanizmust jól szemlélteti a biopsziás mintákban jelen lévő vakuolizált izomrostok, illetve a gyulladásos sejtek által körülvett, nem vakuolizált izomrostok párhuzamos jelenléte. Az MHC-I/CD8 komplex mint specifikus immunmarker bevezetésre került az újonnan kidolgozott diagnosztikus kritériumrendszerben, ez segít elkülöníteni az egyéb izomdisztrófiákban észlelhető aspecifikus gyulladástól. Klinikailag a distalis és proximális izmok érintettsége, légzőizom-gyengeség, dysphagia jellemzi, interstitialis tüdőbetegség nem jellemző. Általában terápiarezisztens, ennek magyarázata lehet a degeneratív folyamatok túlsúlya. Emiatt kortikoszteroid- és egyéb immunszuppresszív terápia sok esetben csak biokémiai választ eredményez, amelyet klinikai válasz nem kísér. A betegség diagnózisa, illetve differenciáldiagnózisa különösen nagy kihívást jelent a gyakorló klinikus számára, tekintettel a specifikus immunhisztokémiai hátteret igénylő diagnosztikus nehézségekre. Az újabb terápiás támadáspontok, kostimulatorikus molekulák elleni antitestek, anticitokin-terápia alkalmazása további előrelépést nyújthat a betegek életminőségének javításában.

The treatment and prognosis of dermatomyositis: an updated review

Dermatomyositis (DM) is an idiopathic inflammatory myopathy. The mainstay of treatment for DM is oral corticosteroids. However, the dose and length of treatment is debated. Adding to the confusion, there have been no randomized controlled studies comparing the use of various corticosteroid doses and taper rates, and no controlled long-term studies assessing the hypothesis that, unlike systemic lupus erythematous, patients with DM can often achieve long-term remission off therapy. This literature review supports an approach that prednisone should be started at about 1 mg/kg/d, which is then tapered slowly based on the response. As patients respond differently to prednisone, additional therapies may be necessary. When to initiate these therapies requires clinical judgment. In addition, as we learn more about the pathophysiology of DM, newer medications that target specific mechanisms in the immune response may help us better treat the disease. Evidence-based data with long-term follow-up will allow for selection of the best treatment to maximize long-term remission, not simply short-term lowering of the systemic corticosteroid dose.

[Current treatments of dermatomyositis and polymyositis]

Idiopathic inflammatory myositides are chronic diseases affecting predominantly the musculoskeletal system and involving high morbidity and mortality. Even when treated with glucocorticosteroids, patients often experience a progressive or relapsing course of the disease, requiring additional immunosuppressants, biologicals, or other therapeutic interventions. Randomized controlled trials on the treatment of primary myositides are still lacking, which means that the optimum therapeutic regimen has still not been defined. This article reviews the current position indicated by the data collected in standard and modern therapeutic options for the treatment of idiopathic inflammatory myositides.

Advances in the immunobiology and treatment of inflammatory myopathies

The clinical spectrum and immunopathogenesis of inflammatory myopathies are summarized with an update on possible triggering factors, cell degeneration, and emerging new therapies.

Inclusion body myositis: current pathogenetic concepts and diagnostic and therapeutic approaches

Inclusion body myositis is the most common acquired muscle disease in older individuals, and its prevalence varies among countries and ethnic groups. The aetiology and pathogenesis of sporadic inclusion body myositis are still poorly understood; however genetic factors, ageing, and environmental triggers might all have a role. Unlike other inflammatory myopathies, sporadic inclusion body myositis causes slowly progressing muscular weakness and atrophy, it has a distinctive pattern of muscle involvement, and is unresponsive to conventional forms of immunotherapy. This review covers the clinical presentation, diagnosis, treatment, and the latest information on genetic susceptibility and pathogenesis of sporadic inclusion body myositis.

Management of the child with weakness

With increased life expectancy associated with improved respiratory care and research advances in pediatric neuromuscular diseases leading to clinical trials involving potential curative treatments, the goal in the care of the child with weakness is to optimize survival and quality of life. The care of the child with weakness includes management of motor dysfunction because of weakness, orthopedic complications of contractures and scoliosis, and comorbid complications specific to each neuromuscular disease. Optimal holistic integrative care of the multisystemic problems of such patients is best provided by the collaborative efforts of health care providers of an interdisciplinary team.