Limited effects of high-dose intravenous immunoglobulin (IVIG) treatment on molecular expression in muscle tissue of patients with inflammatory myopathies

Myocarditis in connective tissue diseases: an often-overlooked clinical manifestation

To discuss what is currently known about myocarditis in the context of major connective tissue diseases, including Systemic lupus erythematosus, Rheumatoid Arthritis, Sjogren, Dermato-myositis and Polymyositis, Systemic Sclerosis, and Mixed connective tissue disease. Variability exists between studies regarding the incidence of myocarditis in connective tissue diseases, which is hypothesized to be the result of its subclinical course in most cases. Extensive gaps of knowledge exist in the field of pathophysiology. Although endomyocardial biopsy remains to be the gold standard for diagnosis, the advancement in non-invasive modalities such as cardiac MRI, echocardiography, and nuclear medicine has allowed for earlier and more frequent detection of myocarditis. A lack of treatment guidelines was found across the different connective tissue diseases. Most of the literature available revolved around myocarditis in the context of Systemic lupus erythematosus. Numerous recent studies were published that contributed to advancements in diagnosis and treatment however, there remains a lack of diagnostic and treatment guidelines.

Intravenous Immunoglobulin for Inflammatory Myositis: Experience in a Tertiary Medical Center

INTRODUCTION

Inflammatory myopathies are treated with glucocorticoids and other immunosuppressive medications. Intravenous immunoglobulin (IVIG) is increasingly used for refractory or severe cases; however, the evidence for their effectiveness is limited. We assessed effectiveness and safety of IVIG when used with other immunomodulatory agents in the treatment of inflammatory myopathies.

METHODS

This study reviewed records of patients diagnosed with dermatomyositis or polymyositis and treated with IVIG, from 2009 through 2016 in 1 tertiary medical center. Mixed-effects general linear regression models were applied to determine effectiveness of treatment on muscle strength, creatinine phosphokinase levels, and steroid dosage.

RESULTS

Twenty-three patients with dermatomyositis/polymyositis treated with IVIG were followed up for a mean of 31 (SD, ±25) months. During this period, a significant improvement in muscle strength was demonstrated, with a mean increase of 0.92 Medical Research Council scale points (β = 0.14; confidence interval [CI], 0.136-0.149; p < 0.0001), a significant reduction of creatinine phosphokinase levels and steroid dosage with a mean decrease of 1140 IU/L (β = -0.274; CI, -0.354 to -0.195; p < 0.0001), and 36 mg/d (β = -0.008; CI, -0.011 to -0.006; p < 0.0001), respectively. Overall, remission was observed in 10 patients (43.5%), and partial remission in 6 patients (26%), whereas 1 patient (17%) remained refractory to treatment, and 6 patients (27%) were lost to follow-up.

CONCLUSIONS

The majority of patients with inflammatory myopathies experienced a clinical and laboratory improvement during IVIG treatment. In addition, a steroid-sparing effect was noticed in most patients. These results encourage the use of IVIG as an alternative treatment option for patients with limited responsiveness to conventional methods.

Long-term effects of early pulse methylprednisolone and intravenous immunoglobulin in patients with dermatomyositis and polymyositis

OBJECTIVE

To evaluate the long-term effects of pulse intravenous methylprednisolone (IVMP) or intravenous immunoglobulin (IVIG) administered during the first year of diagnosis in dermatomyositis (DM) and polymyositis (PM) patients.

METHODS

This is a retrospective single-center cohort study of patients with DM/PM followed for up to 4 years from 2001 to 2017. We used Cox regression models to estimate hazard ratios (HRs) and assess the effects of early pulse IVMP or IVIG on 3 outcomes: complete clinical response, corticosteroid discontinuation, and survival. Analysis was adjusted for clinical, laboratory, and treatment covariates.

RESULTS

A total of 204 patients were included and categorized into 4 initial treatment groups: pulse IVMP (n = 46), pulse IVMP+IVIG (n = 55), IVIG (n = 10), and without IVMP or IVIG (n = 93). The groups of early pulse IVMP and pulse IVMP+IVIG had a higher HR for complete clinical response in the multivariate models (HR = 1.56, 95% CI = 1.05-2.33, p = 0.029; and HR = 1.58, 95% CI = 1.02-2.45, p = 0.041, respectively). Only the group of pulse IVMP+IVIG had a significant association with corticosteroid discontinuation in the multivariate analysis (HR = 1.65, 95% CI = 1.02-2.68, p = 0.043). Early pulse IVMP or IVIG had no impact on mortality.

CONCLUSION

Despite having a more severe disease profile, patients with DM/PM submitted to pulse IVMP or pulse IVMP+IVIG during the first year of diagnosis had a higher HR for complete clinical response, whereas the combination of pulse IVMP+IVIG had an association with corticosteroid discontinuation. Prospective long-term studies are warranted to confirm these benefits of early pulse IVMP and IVIG on patients with DM/PM.

Real life picture of the use of intravenous immunoglobulins in idiopathic inflammatory myopathies: Results of a multicentric study

BACKGROUND

despite the absence of specific guidelines, the treatment with intravenous immunoglobulins (IvIg) is considered effective in patients with refractory idiopathic inflammatory myopathies (IIM). The aim of our study is to evaluate the effectiveness and the safety of IvIg and define the possible profile of IIM patients candidate to IvIg treatment.

METHODS

we performed a retrospective study of IIM pts. treated with IvIg (2 g/kg/month). We collected demographic, epidemiological, laboratory and clinical data. Additionally, to evaluate the toxicity, the adverse events occurred during the treatment were collected.

RESULTS

123 patients with IIM were included in the study. The main indications for the prescription of IvIg were muscle (83.7% of patients) and esophageal involvement (45.5% of patients). IvIg were started mainly for refractory disease. At the end of treatment (mean duration 14 months), muscular necrosis enzymes decreased significantly and dysphagia VAS decreased significantly (p < 0.001), while MMT value increased (104.6 ± 24.2 vs. 127.0 ± 22.2 p < 0.001). Ninety-six pts. (78%) responded to IvIg. They had a shorter disease duration (p < 0.001), higher creatine kinase levels (p < 0.001), and higher prevalence of myalgias at the baseline (p = 0.023) compared to non-responders. The presence of Raynaud's phenomenon (p = 0.023-odds ratio 0.28 [0.11-0.72]) and skin involvement (p = 0.004, odds ratio 0.18 [0.06-0.55]), were associated to a worse response. Adverse events were mostly mild and transitory.

CONCLUSIONS

Despite their high cost, IvIg confirmed their effectiveness in refractory IIM pts., particularly in muscular and esophageal manifestations. Specific clinical characteristics at the baseline may identify the patients with higher probability of response to the treatment.

A rare form of dermatomyositis associated with muscle weakness and normal creatine kinase level

We present a case study of a 61-year-old Vietnamese woman who presents with features of dermatomyositis (DM), including Gottron’s papules, heliotrope rash, cutaneous ulcers, generalised weakness and pain, and weight loss with normal levels of creatine kinase (CK). She demonstrated features of interstitial lung disease and subsequently tested positive for anti-melanoma differentiation-associated gene 5 and anti-small ubiquitin-like modifier 1 activating enzyme antibodies, which belong to a DM subtype known as clinically amyopathic dermatomyositis and do not present with raised CK. She received standard treatment for DM, including oral prednisolone, hydroxychloroquine, mycopheonlate and topical betamethasone. The treatment successfully reversed skin changes; however, the patient remained generally weak and unable to carry out her activities of daily living.

Recovering autonomy is a key advantage of home-based immunoglobulin therapy in patients with myositis: A qualitative research study

Immunoglobulins are 2nd or 3rd-line treatments in dermatomyositis (DM) or polymyositis (PM) refractory to high-dose corticosteroids and immunosuppressants. Immunoglobulins (2 g/kg/mo) are usually administered intravenously (IVIg) once a month and the patients stay at hospital for a few days. Recently, subcutaneous injections (SCIg) were proposed 2 to 3 times per week, in some dysimmune diseases. SCIg are administered at home preferably by the patient or by a nurse. We investigated the needs and attitudes of DM and PM patients with experience of IVIg and SCIg.Seven patients (6 PM and 1 DM) from a single center participated in a focus group (N = 6) or underwent in-depth interview (N = 1). Six had the experience of both IVIg at hospital and SCIg at home; 1 has received only IVIg at hospital. Verbatim was recorded and transcribed for further content analysis and computer-aided textual analysis.Clinical profiles and stories were heterogeneous. At diagnosis, muscle weakness, severe pain, and fatigue were at the forefront of patients' complaints impairing daily life. Patients reported considerable improvement with immunoglobulins. SCIg were described as easy, less disruptive for daily life, well tolerated, and less time-consuming. SCIg self-administration at home restored the feeling of autonomy and control.Interviews of DM and PM patients revealed that recovering autonomy and control was a central advantage of home-based SCIg that were efficient, well tolerated, and perceived as a good compromise between treatment burden and efficacy.

Immunoglobulin Treatment in Neuromuscular Medicine

Intravenous immunoglobulin (IVIg) is used in the treatment of autoimmune diseases, including immune-mediated central and peripheral nervous system disorders. This article will review the indications, proposed mechanism of actions, and administration of immunoglobulin treatment in various neuropathies, neuromuscular junction disorders, and myopathies. IVIg may have more than one mechanism of action to alter the pathogenesis of underlying neuromuscular disease. IVIg treatment has been used as a first-line treatment in Guillain-Barre syndrome, chronic inflammatory demyelinating polyradiculoneuropathy, multifocal motor neuropathy, and second-line off-label treatment in medically refractory cases of polymyositis, dermatomyositis, and myasthenia gravis. IVIg is a well-tolerated and effective treatment for these neuromuscular diseases. With this review article, we hope to increase clinicians' awareness of the indications and efficiencies of IVIg in a broad spectrum of neuromuscular diseases.

Current Treatment for Myositis

PURPOSE OF REVIEW

The purpose of this review was to give an update on treatment modalities for patients with idiopathic inflammatory myopathies, or shortly myositis, excluding the subgroup inclusion body myositis, based on a literature survey on therapies used in myositis. Few controlled trials have been performed in patients with myositis; therefore, we also included a summary of open-label trials, case series, and case reports.

RECENT FINDINGS

Glucocorticoid (GC) in high doses is still the first-line treatment of patients with myositis. There is a general recommendation to combine GCs with another immunosuppressive agent in the early phase of disease to better control disease activity and possibly to reduce the risk for GC-related side effects. Furthermore, combining pharmacological treatment with individualized and supervised exercise can be recommended based on evidence. There is some evidence for the effect of rituximab in patients with certain myositis-specific autoantibodies, whereas other biologic agents are currently being tested in clinical trials.

SUMMARY

Immunosuppressive treatment in combination with exercise is recommended for patients with myositis to reduce disease activity and improve muscle performance. Subgrouping of patients into clinical and serological subtypes may be a way to identify biomarkers for response to specific immunosuppressive and biological agents and should be considered in future trials.

Treatment of inflammatory myopathies

INTRODUCTION

The idiopathic inflammatory myopathies (IIM) dermatomyositis (DM) and polymyositis (PM) are chronic diseases affecting the striated muscles with variable involvement of other organs. Glucocorticoids are considered the cornerstone of treatment, but some patients require adjunctive immunosuppressive agents because of insufficient response to glucocorticoids, flares upon glucocorticoid tapering, or glucocorticoid-related adverse events. Areas covered: The aim of this article was to review (PubMed search until February 2018) the evidence on established and new therapies derived from randomized controlled trials (RCTs) on adult DM and PM. In addition, key data from open-label trials, case reports, and abstracts were included where data from RCT were lacking. Expert commentary: Numerous synthetic and biological immunosuppressive agents are currently available to treat the IIM, sometimes in combination. The choice of the specific medication in the individual patient depends upon the disease phenotype and patient's characteristics. Exercise improves muscle performance without causing disease flares and should be an integral part of the treatment of the IIM. Prompt diagnosis and treatment can lead to better outcome.

IFN-β-induced reactive oxygen species and mitochondrial damage contribute to muscle impairment and inflammation maintenance in dermatomyositis

Dermatomyositis (DM) is an autoimmune disease associated with enhanced type I interferon (IFN) signalling in skeletal muscle, but the mechanisms underlying muscle dysfunction and inflammation perpetuation remain unknown. Transcriptomic analysis of early untreated DM muscles revealed that the main cluster of down-regulated genes was mitochondria-related. Histochemical, electron microscopy, and in situ oxygraphy analysis showed mitochondrial abnormalities, including increased reactive oxygen species (ROS) production and decreased respiration, which was correlated with low exercise capacities and a type I IFN signature. Moreover, IFN-β induced ROS production in human myotubes was found to contribute to mitochondrial malfunctions. Importantly, the ROS scavenger N-acetyl cysteine (NAC) prevented mitochondrial dysfunctions, type I IFN-stimulated transcript levels, inflammatory cell infiltrate, and muscle weakness in an experimental autoimmune myositis mouse model. Thus, these data highlight a central role of mitochondria and ROS in DM. Mitochondrial dysfunctions, mediated by IFN-β induced-ROS, contribute to poor exercise capacity. In addition, mitochondrial dysfunctions increase ROS production that drive type I IFN-inducible gene expression and muscle inflammation, and may thus self-sustain the disease. Given that current DM treatments only induce partial recovery and expose to serious adverse events (including muscular toxicity), protecting mitochondria from dysfunctions may open new therapeutic avenues for DM.

Critical review of the role of intravenous immunoglobulins in idiopathic inflammatory myopathies

OBJECTIVE

The aim of this review was to summarize key findings from the literature concerning the therapeutic role of intravenous immunoglobulins (IVIg) in idiopathic inflammatory myopathies (IIM), dissecting the evidence according to disease subtype and treatment indication, and to review the evidence relating to the mechanism of action of IVIg in IIM to ascertain rationale for continued research.

METHODS

Medline (Ovid) and Pubmed databases were searched from inception to July 2016 using relevant keywords. Original and review articles were retrieved for full-text review. Bibliographies of selected articles were also hand-searched for additional references. Data were summarized qualitatively and in tabular form.

RESULTS

The efficacy of IVIg in IIM is supported by 3 randomized controlled trials, involving dermatomyositis and polymyositis subjects, in refractory, relapsed, or steroid-dependent disease, as well as part of first-line therapy in elderly dermatomyositis subjects. Other indications for IVIg are supported by uncontrolled evidence only. Limitations of studies include open, uncontrolled or retrospective study designs, small and selected samples, short-term follow-up and ad hoc outcome measures. Despite the limited evidence, there is strong biological plausibility for the role of IVIg in IIM.

CONCLUSION

Robust, controlled evidence to support the use of IVIg using validated outcome measures is urgently required to guide therapeutic decision-making and maximize outcomes in IIM.

Intravenous immune globulin suppresses angiogenesis in mice and humans

Human intravenous immune globulin (IVIg), a purified IgG fraction composed of ~60% IgG1 and obtained from the pooled plasma of thousands of donors, is clinically used for a wide range of diseases. The biological actions of IVIg are incompletely understood and have been attributed both to the polyclonal antibodies therein and also to their IgG (IgG) Fc regions. Recently, we demonstrated that multiple therapeutic human IgG1 antibodies suppress angiogenesis in a target-independent manner via FcγRI, a high-affinity receptor for IgG1. Here we show that IVIg possesses similar anti-angiogenic activity and inhibited blood vessel growth in five different mouse models of prevalent human diseases, namely, neovascular age-related macular degeneration, corneal neovascularization, colorectal cancer, fibrosarcoma and peripheral arterial ischemic disease. Angioinhibition was mediated by the Fc region of IVIg, required FcγRI and had similar potency in transgenic mice expressing human FcγRs. Finally, IVIg therapy administered to humans for the treatment of inflammatory or autoimmune diseases reduced kidney and muscle blood vessel densities. These data place IVIg, an agent approved by the US Food and Drug Administration, as a novel angioinhibitory drug in doses that are currently administered in the clinical setting. In addition, they raise the possibility of an unintended effect of IVIg on blood vessels.

Th17 cells reflect colon submucosal pathologic changes in active eosinophilic granulomatosis with polyangiitis

BACKGROUND

Chronic eosinophilic pneumonia (CEP) or eosinophilic gastroenteritis (EG), or both, with asthma precede the onset of eosinophilic granulomatosis with polyangiitis (EGPA) in half of all EGPA patients. It is not known what determines whether patients with CEP or with EG following asthma will develop EGPA.

METHODS

We studied 17 EGPA patients and 12 patients with CEP but without EGPA. We assayed serum ICAM-1, VCAM-1, and VEGF, and the percentage of peripheral blood CD4(+) T cells producing IL-17 (Th17 cells), at both onset and remission. We also examined the numbers of submucosal eosinophils and the basement membrane-to-crypt and crypt-to-crypt distance to evaluate edema in the colon submucosa at onset and remission in EGPA and at onset in CEP.

RESULTS

Nine of 12 (75.0%) CEP patients had symptoms or endoscopic findings. Colonic submucosal eosinophil counts and edema in EGPA at onset were greater than at remission or in CEP at onset. Th17 cells (%) and serum ICAM-1 levels at onset were greater in EGPA than in CEP. In EGPA, peripheral blood Th17 cells (%) were significantly correlated with serum ICAM-1 level, colonic submucosal eosinophil count, and degree of edematous change; inversely correlated with serum VEGF level; but not correlated with VCAM-1 level.

CONCLUSIONS

Eosinophilia and colonic submucosal edematous change were greater in EGPA than in CEP. The mechanism of vasculitis in EGPA appears related to increases in serum Th17 cell numbers and ICAM-1 levels and decreases in VEGF levels.

Clinical applications of immunoglobulin in neuromuscular diseases: focus on inflammatory myopathies

During recent years, an increasing number of neuromuscular diseases have been recognized either to be caused primarily by autoimmune mechanisms, or to have important autoimmune components. The involved pathophysiological mechanisms and clinical manifestations have been better recognized and many of these disorders are potentially treatable by immunosuppression or by immunomodulation with intravenous immunoglobulin (IVIg). IVIg has been tried in a variety of immune-mediated neurological diseases, being target of widespread use in central and peripheral nervous systems diseases.

OBJECTIVE

To give an overview of the main topics regarding the mechanism of action and different therapeutic uses of IVIg in neurological practice, mainly in neuromuscular diseases.

Idiopathic inflammatory myopathies: current trends in pathogenesis, clinical features, and up-to-date treatment recommendations

Recently, there have been important advances in the understanding of the pathophysiologic features, assessment, and management of patients with a newly diagnosed idiopathic inflammatory myopathy (IIM). Myositis-specific autoantibodies have been identified to define patient subgroups and offer prognostic implications. Similarly, proinflammatory cytokines, such as interleukin 6 and type 1 interferon-dependent genes, may serve as potential biomarkers of disease activity in adult and juvenile patients with dermatomyositis (DM). Moreover, magnetic resonance imaging has become an important modality for the assessment of muscle inflammation in adult IIM and juvenile DM. Immune-mediated necrotizing myopathies also are being recognized as a subset of IIM triggered by medications such as statins. However, confusion exists regarding effective management strategies for patients with IIM because of the lack of large-scale, randomized, controlled studies. This review focuses primarily on our current management and treatment algorithms for IIM including the care of pediatric patients with juvenile DM. For this review, we conducted a search of PubMed and MEDLINE for articles published from January 1, 1970, to December 1, 2011, using the following search terms: idiopathic inflammatory myopathies, dermatomyositis, polymyositis, juvenile dermatomyositis, sporadic inclusion body myositis, inclusion body myositis, inflammatory myositis, myositis, myopathies, pathogenesis, therapy, and treatment. Studies published in English were selected for inclusion in our review as well as additional articles identified from bibliographies.

Clinical trials roundup in idiopathic inflammatory myopathies

PURPOSE OF REVIEW

To review recent advances in the treatment of idiopathic inflammatory myopathies (IIMs) with emphasis on new biological agents and on some less commonly used immunosuppressive drugs.

RECENT FINDINGS

Double-blinded comparison of oral high-dose pulse dexamethasone with standard high daily prednisolone doses showed similar efficacy in the composite score, significantly longer median time to relapse with prednisolone and fewer side effects with dexamethasone treatment. Use of intravenous immunoglobulins (IVIGs) in IIMs is associated with variable results; however, recent retrospective evaluation of IVIGs administration to steroid-resistant patients with esophageal involvement showed good effect. Whereas smaller open studies with rituximab reported a very good efficacy, even in notoriously difficult-to-treat anti-signal recognition particle-positive cases, the double-blind trial has not reached the primary endpoint. Studies with TNF neutralization are reporting results ranging from only a modest or no effect to a promising outcome in the most recent trial with etanercept. Pilot studies suggest efficacy of alemtuzumab in inclusion body myositis and allogeneic mesenchymal stem cell transplantation in polymyositis/dermatomyositis.

SUMMARY

Unmet need for efficacious therapy in IIMs exists and therefore a coordinated effort is necessary to properly evaluate various new classical and biological agents.

Intravenous immunoglobulin therapy in rheumatic diseases

Prepared from the collective plasma of several thousand people, therapeutic intravenous immunoglobulin (IVIg) consists mostly of human polyspecific IgG. In addition to its use in primary and secondary immune deficiencies, IVIg is used in the treatment of several rheumatic conditions, including Kawasaki disease, dermatomyositis and antineutrophil cytoplasmic antibody (ANCA)-positive vasculitis. In these diseases, IVIg therapy generally involves the use of 2 g/kg administered over either 2 or 5 consecutive days. However, dosage regimens have not been thoroughly explored, and indications for IVIg in most rheumatic diseases, such as systemic lupus erythematosus, polymyositis and catastrophic antiphospholipid syndrome, derive from its off-label usage. Randomized clinical trials are warranted to support the evidence-based use of IVIg, and to identify the ideal administration protocols to maximize the benefits of what is a limited resource. Further research to improve the therapeutic application of IVIg relies essentially on the conception of next-generation immunoglobulin preparations and optimization of combined therapies with immunomodulatory drugs and biologic agents.

Cardiological features in idiopathic inflammatory myopathies

Idiopathic inflammatory myopathies (IIMs) represent a heterogeneous group of autoimmune systemic diseases characterized by chronic muscle weakness and inflammatory cell infiltrates in skeletal muscle. The most frequent IIMs, such as adult-onset polymyositis and dermatomyositis, display a wide range of clinical manifestations other than myositis, including skin changes, Raynaud's phenomenon and interstitial lung disease. Cardiac involvement is now well recognized as a clinically important manifestation in patients with polymyositis or dermatomyositis, although its actual frequency is still uncertain. Cardiovascular complications represent one of the most frequent causes of death in myositis, apart from cancer and lung involvement. Despite the fact that clinical manifestations are relatively rare, asymptomatic cardiovascular features are frequently reported in patients with polydermatomyositis and dermatomyositis. They are characterized by isolated electrocardiographic changes, valve disease, coronary vasculitis, ischemic abnormalities, heart failure and myocarditis. Chronic inflammation producing myocyte degeneration, tissues fibrosis and vascular alterations can explain the majority of reported cardiac features in myositic patients. Although previous works reported an association between heart involvement and some myositis-specific autoantibodies (namely anti-signal recognition particle), electrocardiography, echocardiography and, where necessary, heart magnetic resonance remain the mainstay for diagnosing and monitoring myocardial inflammation in these diseases. Anyway, a complete multiorgan assessment and a careful analysis of autoantibodies should be performed in every patient in order to define any possible distinct disease entities with different prognosis within the spectrum of IIMs.

A longitudinal, integrated, clinical, histological and mRNA profiling study of resistance exercise in myositis

Polymyositis and dermatomyositis are orphan, chronic skeletal muscle disorders characterized by weakness, infiltrations by mononuclear inflammatory cells, and fibrosis. Until recently, patients were advised to refrain from physical activity because of fears of exacerbation of muscle inflammation. However, recent studies have shown that moderate exercise training in combination with immunosuppressive drugs can improve muscle performance. Despite the positive effects of exercise training, the molecular mechanisms underlying the exercise-associated clinical improvements remain poorly understood. The present study was designed to define, at the molecular level, the effects of resistance exercise training on muscle performance and disease progression in myositis patients. We evaluated changes in muscle strength, histology and genome-wide mRNA profiles to determine the beneficial effects of exercise and determine the possible molecular changes associated with improved muscle performance. A total of 8 myositis patients underwent a 7-wk resistance exercise training program that resulted in improved muscle strength and increased maximal oxygen uptake (VO(2max)). Training also resulted in marked reductions in gene expression, reflecting reductions in proinflammatory and profibrotic gene networks, changes that were also accompanied by a reduction in tissue fibrosis. Consistent with the exercise-associated increase in VO(2max), a subset of transcripts was associated with a shift toward oxidative metabolism. The changes in gene expression reported in the present study are in agreement with the performance improvements induced by exercise and suggest that resistance exercise training can induce a reduction in inflammation and fibrosis in skeletal muscle.

Rituximab as a first-line agent for the treatment of dermatomyositis

B cells may play a pivotal role in the pathophysiology of DM, and reports have claimed that targeting B cells is a viable treatment option in patients with dermatomyositis. A 20-year-old girl presented in October 2007, with few weeks' history of proximal muscle weakness. Gottron's papules were noted on her knuckles. She had normal inflammatory markers and negative autoantibody screen. Her CPK was 7,000 U/L (normal range 0-170) with an LDH of 1,300 U/L (normal range 266-500). EMG and muscle biopsy was consistent with active myositis. She had normal pulmonary function tests. HRCT showed no interstitial lung disease. She was started with 60 mg glucocorticoids (1 mg/kg), with a good clinical response. However, any attempt to taper down the steroid dose led to recurrence of her symptoms. The options of available immunosuppressive therapies, including the experimental usage of rituximab, were discussed with her; averse to long-term systemic treatments, she opted to try a course of rituximab. She had rituximab 1,000 mg on days 0 and 14, and her glucocorticoids were tapered in next few weeks. Now, 24 months since her rituximab infusions, she remains in complete clinical and biochemical remission and is naïve to other immunosuppressive agents apart from glucocorticoids and rituximab. Depleting peripheral B cells with rituximab (one course) in our patient has led not only to complete resolution of muscle and skin disease (induction) but also remains off all immunosuppressives including glucocorticoids.

Favorable outcome of juvenile dermatomyositis treated without systemic corticosteroids

OBJECTIVE

To describe the course of patients with juvenile dermatomyositis (JDM) treated effectively without systemic corticosteroids.

STUDY DESIGN

A retrospective study of 38 patients with JDM treated at a tertiary care children's hospital identified 8 patients who had never received corticosteroids. Disease presentation and course, pharmacologic, and ancillary treatments were recorded.

RESULTS

Patients in the no corticosteroid group were followed for a median of 2.8 years (range, 2.1 to 9.5 years). Treatment was primarily with intravenous immunoglobulin (IVIG) (75%) and methotrexate (50%), with favorable response in all. No serious treatment complications were observed; headaches were reported by 3 patients receiving IVIG. Two patients had a myositis flare after discontinuing all medications for more than 1 year; complete resolution of symptoms was observed after either 1 or 2 further doses of IVIG. Two patients had calcinosis (at 1 and 9 years of disease); however, no patient had joint contractures, muscle atrophy, lipodystrophy, or functional limitations.

CONCLUSIONS

Systemic corticosteroids can be avoided in a select group of patients with JDM. Alternative agents such as methotrexate and IVIG may be prescribed to effectively treat JDM and prevent complications.

Treatment of inclusion body myositis: is low-dose intravenous immunoglobulin the solution?

Inclusion body myositis (IBM), the most common inflammatory myopathy in the elderly, is often resistant to various forms of therapy. Placebo-controlled treatment trials with high dose intravenous immunoglobulins (IVIG) have shown disease amelioration in some but not all patients. Here, we present the informative case of a 70-year-old woman with diagnosed inclusion body myositis that showed progressive muscle weakness without treatment and following immuno-suppressive treatment with corticosteroids and azathioprine. A trial with low-dose intravenous immunoglobulins was started at that time. The patient responded rapidly to low dose IVIG treatment with amelioration of muscle strength and normalization of CK serum activities. Our results demonstrate that IBM patients may respond to low-dose IVIG treatment which has important clinical and economic consequences.