Malignancy in myositis

Occult ovarian adenocarcinoma manifesting as dermatomyositis

A woman in her 60s presented with erythematous lesions predominantly over the joints. After evaluation by dermatology and rheumatology, she was diagnosed with dermatomyositis and initiated on oral steroids and immunosuppressants. She was subsequently referred to gynaecology services for further evaluation of possible malignancies. On pelvic examination, a firm, mobile mass was noted in the right adnexa which was confirmed on imaging. A decision for staging laparotomy was taken. Intraoperatively, a solid mass was observed in the right ovary with no adjacent tumour deposits. Histopathology indicated high-grade serous carcinoma. Following surgery, her dermatological condition improved drastically, and she is currently off medications. She has received postoperative chemotherapy. Five years on, she is doing well.

A meta-analysis of melanoma risk in idiopathic inflammatory myopathy patients

BACKGROUND

Idiopathic inflammatory myopathy (IIM) is a group of chronic acquired autoimmune diseases. The association between IIM and malignancies has been observed for decades. No meta-analysis has been conducted to summarize the relationship between IIM and melanoma. Herein, we specifically wanted to investigate whether IIM is associated with a higher incidence of melanoma.

METHODS

We searched both Chinese and English databases (CNKI, VIP, Wanfang, PubMed, Embase, Web of Science) for studies on IIM related to melanoma published up to October 2023. Two independent authors reviewed all literature to identify studies according to predefined selection criteria. Fixed effects models were applied to pool the risk. Publication bias was also evaluated and sensitivity analysis performed.

RESULTS

A total of 1660 articles were initially identified but only four cohort studies met the criteria. Thus, 4239 IIM patients were followed up. The pooled overall risk ratio/hazard ratio was 3.08 (95% confidence interval [CI] 0.79-5.37) and the standardized incidence ratio was 6.30 (95% CI 1.59-11.02).

CONCLUSION

The present meta-analysis suggests that IIM patients are at a significantly higher risk of developing melanoma.

Predictors of myositis in mixed connective tissue disease: A multicentre retrospective study

OBJECTIVES

We aimed to identify clinical and serological predictors of myositis in mixed connective tissue disease (MCTD).

METHODS

We performed a nationwide, retrospective, multicentre study including adult-onset MCTD patients fulfilling at least one of the following diagnostic criteria: Sharp's, Kasukawa, Alarcón-Segovia, or Kahn's. Univariate analysis was performed using Chi-square, Fisher exact, Student's t or Mann-Whitney U tests, as appropriate. Multivariate analysis was performed using binary logistic regression.

RESULTS

Ninety-eight patients were included. Myositis was observed in 43.9% of patients, of whom 60.5% had myositis at disease onset. Proximal muscle weakness was described in 30 patients with muscle involvement (70%). Gastrointestinal involvement was identified in 28% and respiratory involvement in 29% of myositis patients. In the same subgroup of patients, 41.7% had a myopathic pattern on electromyography, and 47.1% had histological myositis features in the muscle biopsy. Fever (OR=6.96, p=0.022) was an independent predictor of myositis, regardless of sex, age at diagnosis, ancestry, and respiratory involvement. African ancestry (OR=8.39, p=0.019), leukopenia at the disease onset (OR 6.24, p=0.021), and younger age at diagnosis (OR=1.07/year, p=0.035) were identified as independent predictors of myositis at disease onset, regardless of sex and scleroderma pattern in capillaroscopy.

CONCLUSIONS

Myositis is a common manifestation of MCTD, even at the disease onset. African ancestry, leukopenia at the disease onset, younger age at diagnosis, and fever should prompt a thorough evaluation for myositis.

Causality Assessment Between Idiopathic Inflammatory Myopathies and Lung Cancer: A Bidirectional 2-Sample Mendelian Randomization

BACKGROUND

Although observational studies have revealed associations between idiopathic inflammatory myopathies (IIMs) and lung cancer (LC), they have not established a causal relationship between these 2 conditions.

METHODS

We used a 2-sample Mendelian randomization approach to examine the bidirectional causal associations between IIMs and LC, using single-nucleotide polymorphisms selected from high-quality genome-wide association studies in the FinnGen database. Sensitivity analyses were conducted to assess potential heterogeneity and pleiotropy impacts on the Mendelian randomization results.

RESULTS

Our analysis demonstrated a positive causal effect of genetically increased IIM risk on LC (odds ratio, 1.114; 95% confidence interval, 1.057-1.173; p = 5.63 × 10 -5 ), particularly on the lung squamous cell carcinoma subtype (odds ratio, 1.168, 95% confidence interval, 1.049-1.300, p = 0.00451), but not on lung adenocarcinoma or small cell lung cancer. No causal effect of LC on IIMs was identified. Sensitivity analyses indicated that horizontal pleiotropy was unlikely to influence causality, and leave-one-out analysis confirmed that the observed associations were not driven by a single-nucleotide polymorphism.

CONCLUSION

Our findings offer compelling evidence of a positive causal relationship between IIMs and LC, particularly with regard to lung squamous cell carcinoma, in the European population. Conversely, there is no evidence of LC causing IIMs. We recommend that LC diagnosis consider the specific characteristics of IIMs.

Small cell lung cancer with dermatomyositis: a case report

Dermatomyositis represents an autoimmune disorder characterized by notable skin and muscular manifestations. The annual incidence of dermatomyositis stands at approximately (5~10)/1 million individuals. Notably, patients with malignant tumors exhibit an elevated risk of developing dermatomyositis compared to the general population. However, in cases where dermatomyositis co-occurs with malignancy, the efficacy of hormone therapy alone tends to be suboptimal. Moreover, reports addressing the correlation between tumor treatment and the management of dermatomyositis are scarce. A 60-year-old male patient presented with dermatomyositis, initially manifesting through symptoms such as rash, muscle weakness, and dysphagia. Despite undergoing standard hormone therapy, there was no discernible improvement in the dermatomyositis symptoms. Considering the patient's concomitant troublesome cough, further investigations were conducted, including CT, PET-CT, and pathological biopsy. These assessments confirmed the diagnosis of limited-stage small cell lung cancer (T1cN3M0 IIIB). Notably, in this patient, dermatomyositis was suspected to be a paraneoplastic syndrome associated with small cell lung cancer. Standard chemotherapy and radiotherapy were employed to treat the small cell lung cancer, resulting in partial remission after two treatment cycles. As the malignancy regressed, a notable improvement in dermatomyositis symptoms was observed, subsequently leading to a gradual reduction in the prescribed hormone dosage. In conclusion, we present a comprehensive case study of dermatomyositis as a paraneoplastic syndrome throughout the treatment process. The response to tumor therapy coincided with the amelioration of dermatomyositis symptoms. Therefore, diligent malignancy screening is imperative for patients diagnosed with dermatomyositis.

Paraneoplastic myopathy-related rhabdomyolysis and pancreatic cancer: A case report and review of the literature

BACKGROUND

Rhabdomyolysis is a life-threatening condition, often leading to progressive renal failure and death. It is caused by destruction of skeletal muscle and the release of myoglobin and other intracellular contents into the circulation. The most frequent cause of this condition is "crush syndrome", although several others have been described and paraneoplastic inflammatory myopathies associated with various types of cancer are repeatedly reported.

CASE SUMMARY

We describe a rare case of a patient with pancreatic cancer who developed rhabdomyolysis early on, possibly due to paraneoplastic myositis leading to acute renal failure and eventually to rapid death. A 78-year-old Caucasian woman was referred to our hospital for obstructive jaundice and weight loss due to a lesion in the pancreatic head. She presented increasingly severe renal insufficiency with anuria, a dramatic increase in creatine phosphokinase (36000 U/L, n.v. 20-180 U/L) and myoglobin (> 120000 μg/L, n.v. 12-70 μg/L). On clinical examination, the patient showed increasing pain in the lower limbs associated with muscle weakness which was severe enough to immobilize her. Paraneoplastic myopathy linked to the malignant lesion of the pancreatic head was suspected. The patient was treated with hemodialysis and intravenous methylprednisolone. Despite all the efforts to prepare the patient for surgery, her general condition rapidly deteriorated and she eventually died 30 d after hospital admission.

CONCLUSION

The possible causes of rhabdomyolysis in this patient with pancreatic cancer are discussed, the development of paraneoplastic myopathy being the most likely. Clinicians should bear in mind that these syndromes may become clinically manifest at any stage of the cancer course and their early diagnosis and treatment could improve the patient's prognosis.

Clinical associations of patients with anti-3-hydroxy-3-methylglutaryl CoA reductase antibody-associated immune-mediated necrotising myopathy

BACKGROUND

Anti-3-hydroxy-3-methylglutaryl CoA reductase (HMGCR) antibodies are associated with a subtype of immune-mediated necrotising myopathy (IMNM).

AIMS

To determine clinical associations of anti-HMGCR antibodies for anti-HMGCR-associated IMNM (HMGCR-IMNM) among a cohort of patients in Western Australia and to determine whether serial HMGCR antibody levels parallel disease activity.

METHODS

Adult patients with positive anti-HMGCR antibodies detected by enzyme-linked immunosorbent assay between January 2015 and November 2019 were included. Symptoms, examination findings, imaging findings and blood test results were reviewed retrospectively using patient records and laboratory database results.

RESULTS

Among 26 patients with positive anti-HMGCR antibodies, 23 were diagnosed with HMGCR-IMNM representing a positive predictive value (PPV) of 88%. Myopathy was frequently severe at diagnosis with limb weakness graded as Medical Research Council score 3 or below in 78% of patients, bulbar muscle weakness in 39% and an average creatine kinase (CK) at diagnosis of 7986 U/L. The majority (83%) required at least two therapies to maintain remission, 48% had at least one flare of disease and 57% did not achieve CK normalisation. Correlation between CK and anti-HMGCR antibody level at diagnosis was low (r = 0.04). Anti-HMGCR antibodies fell with treatment in 10 of 12 patients, but remained persistently positive in 83% of patients.

CONCLUSIONS

The PPV of anti-HMGCR antibodies for HMGCR-IMNM in this Western Australian cohort is 88%. Patients typically present with proximal limb weakness, dysphagia and markedly elevated CK, and, despite multiagent immunosuppression, a significant number of patients have evidence of persistent biochemical myositis. Anti-HMGCR antibodies did not correlate with CK levels at diagnosis.

A Case of Paraneoplastic Dermatomyositis Presenting With Malignant Pleural Effusion

Dermatomyositis is an uncommon inflammatory condition characterized by proximal muscle weakness with distinct cutaneous manifestations. Like any other systemic disease, it affects multiple organs, the lungs being one of them. Common pulmonary manifestations of dermatomyositis (DM) include interstitial lung disease (ILD), primary lung malignancy, and aspiration pneumonia. The involvement of the pleura is not commonly seen, and pleural effusion is rarely reported in DM. Its presence should prompt further workup, especially for malignancy. An association between dermatomyositis and malignancy has been studied widely and is well established. Here, we report a 37-year-old female with classical cutaneous manifestations and myopathy of dermatomyositis presenting with a malignant left-sided pleural effusion.

Calcinosis Cutis and Calciphylaxis in Autoimmune Connective Tissue Diseases

Calcinosis represents a severe complication of several autoimmune disorders. Soft-tissue calcifications have been classified into five major types: dystrophic, metastatic, idiopathic, iatrogenic, and calciphylaxis. Autoimmune diseases are usually associated with dystrophic calcifications, including calcinosis cutis, occurring in damaged or devitalized tissues in the presence of normal serum levels of calcium and phosphate. In particular, calcinosis cutis has been described in dermatomyositis, polymyositis, juvenile dermatomyositis, systemic sclerosis, systemic lupus erythematosus, primary Sjögren's syndrome, overlap syndrome, mixed connective tissue disease, and rheumatoid arthritis. Calciphylaxis, a severe and life-threatening syndrome presenting with vascular calcifications and thrombosis, has also been associated with some autoimmune conditions. Due to the potentially disabling character of calcinosis cutis and calciphylaxis, physicians' awareness about the clinical presentation and management of these diseases should be increased to select the most appropriate treatment option and avoid long-term complications. In this review, we aim to analyze the clinical features of calcinosis cutis and calciphylaxis associated with autoimmune diseases, and the main treatment strategies evaluated up to now for treating this potentially disabling disease.

Myositis Multidisciplinary Clinic in a Tertiary Referral Center

Background

Idiopathic inflammatory myopathies (IIM) are a rare heterogeneous group of diseases characterised by chronic skeletal muscle inflammation, but other organs are also frequently involved. IMM represent a diagnostic challenge and a multidisciplinary approach is important to ensure successful diagnosis and adequate follow-up of these patients.

Objective

To describe the general functioning of our multidisciplinary myositis clinic, highlighting the benefits of multidisciplinary team management in patients with confirmed or suspected IIM and to characterise our clinical experience.

Methods

Description of the organization of a dedicated multidisciplinary myositis outpatient clinic, supported by IMM specific electronic assessment tools and protocols based on our Portuguese Register - Reuma.pt. In addition, an overview of our activity between 2017 and 2022 is provided.

Results

An IIM multidisciplinary care clinic, based on a close collaboration between Rheumatologists, Dermatologists and Physiatrist is detailed in this paper. One hundred and eighty-five patients were assessed in our myositis clinic; 138 (75%) of those were female, with a median age of 58 [45-70] years. At the last appointment, 130 patients had a confirmed IIM diagnosis, and the mean disease duration was 4 [2-6] years. The most frequent diagnosis was dermatomyositis (n = 34, 26.2%), followed by antisynthetase syndrome (n = 27, 20.8%) and clinically amyopathic/paucimyopathic dermatomyositis (n = 18, 13.8%). Twenty-four patients (18.5%) were on monotherapy and 94 (72.3%) were on combination therapy.

Conclusion

A multidisciplinary approach is important to ensure the correct diagnosis and follow-up of these patients. A myositis clinic, with a standardised practice at a tertiary hospital level, contributes to a standardization of care and opens research opportunities.

Dermatomyositis Associated with Lung Cancer: A Brief Review of the Current Literature and Retrospective Single Institution Experience

Dermatomyositis is a rare inflammatory myopathy that is often related to lung cancer. In this retrospective observational study, we analyzed data from patients diagnosed with lung cancer at Soroka University Medical Center between January 2017 and July 2021. A total of 689 patients with lung cancer were included in this study, 97 of whom had small cell lung cancer and 592 had non-small cell lung cancer. We identified a single patient (60-year-old female) who presented with signs and symptoms of dermatomyositis, which was later confirmed to be associated with lung cancer as a paraneoplastic syndrome. Both our study and a recent review of the literature illustrate the temporal link between dermatomyositis and lung cancer, as well as reinforce the need for heightened cancer screenings in DM patients.

Clinical and Radiological Features of Interstitial Lung Diseases Associated with Polymyositis and Dermatomyositis

Polymyositis and dermatomyositis are autoimmune idiopathic systemic inflammatory diseases, characterized by various degrees of muscle inflammation and typical cutaneous lesions-the latter found in dermatomyositis. The underlying pathogenesis is characterized by a high level of uncertainty, and recent studies suggest diseases may have different immunopathological mechanisms. In polymyositis, components of the cellular immune system are involved, whereas in dermatomyositis, the pathogenesis is mainly mediated by the humoral immune response. The interstitial lung disease occurs in one-third of polymyositis and dermatomyositis patients associated with worse outcomes, showing an estimated excess mortality rate of around 40%. Lung involvement may also appear, such as a complication of muscle weakness, mainly represented by aspiration pneumonia or respiratory insufficiency. The clinical picture is characterized, in most cases, by progressive dyspnea and non-productive cough. In some cases, hemoptysis and chest pain are found. Onset can be acute, sub-acute, or chronic. Pulmonary involvement could be assessed by High Resolution Computed Tomography (HRCT), which may identify early manifestations of diseases. Moreover, Computed Tomography (CT) appearances can be highly variable depending on the positivity of myositis-specific autoantibodies. The most common pathological patterns include fibrotic and cellular nonspecific interstitial pneumonia or organizing pneumonia; major findings observed on HRCT images are represented by consolidations, ground-glass opacities, and reticulations. Other findings include honeycombing, subpleural bands, and traction bronchiectasis. In patients having Anti-ARS Abs, HRCT features may develop with consolidations, ground glass opacities (GGOs), and reticular opacities in the peripheral portions; nonspecific interstitial pneumonia or nonspecific interstitial pneumonia mixed with organizing pneumonia have been reported as the most frequently encountered patterns. In patients with anti-MDA5 Abs, mixed or unclassifiable patterns are frequently observed at imaging. HRCT is a sensitive method that allows one not only to identify disease, but also to monitor the effectiveness of treatment and detect disease progression and/or complications; however, radiological findings are not specific. Therefore, aim of this pictorial essay is to describe clinical and radiological features of interstitial lung diseases associated with polymyositis and dermatomyositis, emphasizing the concept that gold standard for diagnosis and classification-should be based on a multidisciplinary approach.

Prevention of Adverse Outcomes and Treatment Side Effects in Patients with Neuromuscular Disorders

In this article, we review prevention of serious adverse clinical outcomes and treatment side effects in patients with neuromuscular disorders including myopathies and myasthenia gravis. While neither of these entities is preventable, their course can often be modified, and severe sequelae may be prevented, with the identification of risk factors and proactive attention toward treatment planning.

The associations between myositis autoantibodies and clinical presentations in dermatomyositis

BACKGROUND

The myositis autoantibodies have been widely used clinically in recent years for the identification of an autoantibody-associated clinical phenotype in dermatomyositis (DM) patients. However, correlations between myositis autoantibodies and clinical presentations in different populations are lacking, especially in Taiwan.

OBJECTIVES

To investigate the correlations among cutaneous manifestations, myositis autoantibodies, and systemic diseases, including interstitial lung disease (ILD) and internal malignancy.

METHODS

A retrospective study of patients with histopathologically confirmed cutaneous manifestations of DM was conducted during 2005 to 2020 in Taiwan. A commercial line blot immunoassay technique was used to detect myositis autoantibodies.

RESULTS

A total of 88 DM patients were enrolled, with a mean age of onset of 49.4 years old. The most common systemic features were myositis (56.8%, 50/88), internal malignancy (22.7%, 20/88), dysphagia (19.3%, 17/88), and ILD (17%, 15/88). Among the enrolled patients, 32 patients received serum myositis autoantibodies examination. The most common autoantibodies were ANA (50.7%, 37/73), followed by anti-TIF1-γ (34.4%, 11/32) and anti-MDA5 (31.3%, 10/32) antibodies. Patients with Gottron sign (OR 5.6), arthritis (OR 23.35), or the presence of anti-MDA5 antibody (OR 11.14) were more susceptible to progressing to ILD, whereas patients with pruritus (OR 1.04), dysphagia (OR 6.73), and the presence of ANA (OR 6.29) had significantly higher risks of developing internal malignancies.

CONCLUSIONS

Physicians should pay special attention to certain clinical features, which can help with the early detection of systemic diseases. Cancer screening and myositis autoantibodies examination should be conducted in all DM patients if applicable.

Nationwide epidemiological survey of immunoglobulin G4-related disease with malignancy in Japan

BACKGROUND AND AIM

To clarify the clinicoepidemiological characteristics of immunoglobulin G4 (IgG4)-related disease (IgG4-RD) with malignancy, a nationwide epidemiological survey was conducted.

METHODS

Immunoglobulin G4-related disease patients with malignancy who had visited selected hospitals in Japan were surveyed. The study consisted of two stages: the number of IgG4-RD patients with malignancy was estimated by the first questionnaire and their clinicoepidemiological characteristics were assessed by the second questionnaire.

RESULTS

The frequencies of autoimmune pancreatitis (AIP), IgG4-related sialadenitis, IgG4-related eye disease, IgG4-related kidney disease, and IgG4-related retroperitoneal fibrosis were 44.7%, 20.8%, 14.0%, 5.16%, and 5.12%, respectively. The overall prevalence of malignant disease in IgG4-RD cases was estimated to be 10 900 per 100 000 cases, which was significantly higher than that of malignant disease in the general population. The prevalence of malignant lymphoma in IgG4-RD cases was the highest and was estimated to be 1985 per 100 000 cases. IgG4-related kidney disease had the highest frequency of malignant disease (17.1%). In data from 200 patients, 61 (30.5%) cases of cancer were found 2 years or more before the IgG4-RD diagnosis, 92 cases (46%) during the 1 year preceding or following IgG4-RD diagnosis, and 62 cases of cancer (31%) 2 or more years following IgG4-RD diagnosis.

CONCLUSIONS

The nationwide survey for IgG4-RD with malignancy in Japan showed that IgG4-RD may be related with malignant diseases.

A rare case of docetaxel-induced myositis in a patient with a lung adenocarcinoma

Docetaxel is a cytotoxic taxane frequently used to treat patients with various cancers, including non‐small cell lung cancer (NSCLC). Docetaxel is known to cause acute myalgias, arthralgias, and neuropathy, but there have been few published case reports of myositis. Here, we describe a rare case of docetaxel‐induced myositis diagnosed based on laboratory data, thigh magnetic resonance imaging (MRI), and electromyography (EEG). A 66‐year‐old male was admitted for thigh pain and fatigue that onset 1 week prior. He had been diagnosed with stage IVA (cT4N0M1a) NSCLC 3 years ago and had been started on docetaxel (60 mg/m² intravenously every 3 weeks; fourth‐line chemotherapy) 1 month earlier. After the second cycle, he developed both thigh pain and fatigue. On admission, his creatinine phosphokinase (CPK) level was elevated, thigh MRI revealed diffuse muscle edema, and EEG showed myogenic changes. We found no plausible cause for myositis except docetaxel. He was diagnosed with myositis and treated with oral prednisolone. His symptoms were relieved and the CPK level declined. Although rare, this case indicates that clinicians should consider the possibility of myositis as a complication in patients on docetaxel.

Not a Statin-Induced Myopathy: Metastatic Pancreatic Adenocarcinoma Presenting As Paraneoplastic Myositis

Polymyositis is an inflammatory disease that causes bilateral proximal muscle weakness; unlike dermatomyositis, it is not usually associated with malignancy. However, there are a handful of case reports documenting polymyositis in patients with lymphoma, breast, lung, and bladder cancer. Here we report a case of metastatic pancreatic adenocarcinoma disguised by presenting as polymyositis. Clinical presentation, laboratory values, muscle biopsy, and imaging were all diagnostic of paraneoplastic polymyositis. The patient has significantly improved in symptoms are receiving systemic steroids and pancreaticoduodenectomy.

Update on Malignancy in Myositis—Well-Established Association with Unmet Needs

Idiopathic inflammatory myopathies are a group of rare connective tissue diseases with a well-documented association with malignancy. The mechanisms underlying the increased risk of neoplasms in the course of myositis are not fully understood. The Pubmed database has been thoroughly screened for articles concerning cancer-associated myositis (CAM). The article summarizes the current state of knowledge on the epidemiology and pathogenesis of CAM. Furthermore, it analyses potential risk and protective factors for developing CAM, with particular emphasis on the association with distinct serological profiles. The review summarizes recommendations proposed so far for the management of CAM and presents a novel scheme for cancer screening proposed by the authors. Moreover, promising areas requiring further research were indicated.

Charakteristika von Dermatomyositis-Patienten mit und ohne Malignom-Assoziation

HINTERGRUND

Die Dermatomyositis gehört zur Gruppe der seltenen, idiopathischen, inflammatorischen Myositiden. Für die paraneoplastische Form der Dermatomyositis wurde in der Vergangenheit ein Zusammenhang mit Malignomen erkannt. Faktoren, die für eine Malignom-Assoziation sprechen, werden bis heute untersucht.

PATIENTEN UND METHODIK

Es wurden retrospektiv über einen Zeitraum von 15 Jahren die Daten von 63 Patienten mit Dermatomyositis analysiert.

ERGEBNISSE

Folgende Faktoren gaben einen Hinweis für eine Dermatomyositis mit Malignom-Assoziation: ein höheres Patientenalter (> 52 Jahre [P = 0,001], > 65 Jahre [P = 0,002], ≥ 75 Jahre [P = 0,002]), eine kürzere Zeit zwischen Erstmanifestation und Erstdiagnose (Malignom-Gruppe: 59 Tage vs. Nicht-Malignom-Gruppe: 137 Tage [P = 0,022]), eine Hautbeteiligung in Form von Gottron-Zeichen (P = 0,045), zentrofazialen Erythemen (P = 0,036) oder typischen Erythemen an den Ober-/Unterarmen (P = 0,019), eine oropharyngeale Beteiligung (P = 0,015) und eine GPT-Erhöhung (P = 0,031). Folgende Faktoren sprachen eher gegen eine Malignom-Assoziation: ein jüngeres Patientenalter (≤ 52 Jahre [P = 0,001], 40-65 Jahre [P = 0,045]) und Juckreiz (P = 0,026).

SCHLUSSFOLGERUNGEN

In der Literatur finden sich heterogene Ergebnisse zu den genannten Faktoren hinsichtlich ihrer Eignung als Marker für eine Malignom-Assoziation. Erschwert ist die Faktorenfindung aufgrund kleiner Studienpopulationen, wenigen prospektiven und kontrollierten Studien, die Einordnung von Populationen als Myositis-Patienten ohne Differenzierung und eine inkonsistente Verwendung der Nomenklatur. Mit unserer Studie wollen wir einen wichtigen Beitrag zur Identifizierung von Risikofaktoren bei Dermatomyositis mit Malignom-Assoziation leisten.

Update on Myositis Therapy: from Today's Standards to Tomorrow's Possibilities

Inflammatory myopathies, in short, myositis, are heterogeneous disorders that are characterized by inflammation of skeletal muscle and weakness of arms and legs. Research over the past few years has led to a new understanding regarding the pathogenesis of myositis. The new insights include different pathways of the innate and adaptive immune response during the pathogenesis of myositis. The importance of non-inflammatory mechanisms such as cell stress and impaired autophagy has been recently described. New target-specific drugs for myositis have been developed and are currently being tested in clinical trials. In this review, we discuss the mechanisms of action of pharmacological standards in myositis and provide an outlook of future treatment approaches.

Characteristics of dermatomyositis patients with and without associated malignancy

BACKGROUND

Dermatomyositis belongs to the rare idiopathic, inflammatory myositis group. A previously postulated link between some cases of dermatomyositis and malignancy has been established in recent years. Criteria suggestive of a malignancy association are still being explored.

PATIENTS AND METHODS

We retrospectively analyzed data from 63 patients with dermatomyositis over a period of 15 years.

RESULTS

The following criteria argue for cancer-associated dermatomyositis: older age (> 52 years [P = 0.001], > 65 years [P = 0.002], ≥ 75 years [P = 0.002]), shorter time between manifestation and diagnosis of dermatomyositis (malignancy group: 59 days vs. non-malignancy group: 137 days [P = 0.022]), typical skin involvement such as Gottron sign (P = 0.045), centrofacial erythema (P = 0.036) and typical erythema on the upper arms and forearms (P = 0.019), oropharyngeal involvement (P = 0.015) and increased ALT (P = 0.031). The following criteria argue for non-cancer-associated dermatomyositis: younger age (≤ 52 years [P = 0.001], 40-65 years [P = 0.045]) and pruritus (P = 0.026).

CONCLUSIONS

The aforementioned criteria have been documented in the literature, but reported findings are heterogenous concerning the suitability of their markers for malignancy association. Small study populations, few prospective controlled studies, summarization of different forms of myositis and inconsistent use nomenclature contribute to biased results. Our study aims to make an important contribution toward the identification of risk factors in cancer-associated dermatomyositis.

Noncanonical Functions and Cellular Dynamics of the Mammalian Signal Recognition Particle Components

The signal recognition particle (SRP) is a ribonucleoprotein complex fundamental for co-translational delivery of proteins to their proper membrane localization and secretory pathways. Literature of the past two decades has suggested new roles for individual SRP components, 7SL RNA and proteins SRP9, SRP14, SRP19, SRP54, SRP68 and SRP72, outside the SRP cycle. These noncanonical functions interconnect SRP with a multitude of cellular and molecular pathways, including virus-host interactions, stress response, transcriptional regulation and modulation of apoptosis in autoimmune diseases. Uncovered novel properties of the SRP components present a new perspective for the mammalian SRP as a biological modulator of multiple cellular processes. As a consequence of these findings, SRP components have been correlated with a growing list of diseases, such as cancer progression, myopathies and bone marrow genetic diseases, suggesting a potential for development of SRP-target therapies of each individual component. For the first time, here we present the current knowledge on the SRP noncanonical functions and raise the need of a deeper understanding of the molecular interactions between SRP and accessory cellular components. We examine diseases associated with SRP components and discuss the development and feasibility of therapeutics targeting individual SRP noncanonical functions.

Clinical characteristics of non-infectious inflammatory myopathy in the boxer dog

OBJECTIVES

To evaluate the clinical characteristics, treatment, outcome and potential association between non-infectious inflammatory myopathy and malignancy in boxer dogs.

MATERIALS AND METHODS

Boxer dogs histologically diagnosed with non-infectious inflammatory myopathy at the Comparative Neuromuscular Laboratory, University of California San Diego from 2010 to 2018 and with complete medical records were included in this retrospective study. Signalment, history, clinical signs, clinicopathologic findings, treatment and outcome were documented.

RESULTS

Twenty-eight boxer dogs with non-infectious inflammatory myopathy, aged 1 to 11 years, were included. Eighteen were male (16 neutered; two entire) and 10 were female (seven spayed; three entire). Clinical signs included generalised weakness (n=17), dysphagia (n=11) and weight loss (n=10). Serum creatine kinase activity was elevated in all 20 cases tested (range 908 to 138,000 IU/L). One dog had undifferentiated round cell neoplastic infiltration within the muscle at the time of inflammatory myopathy diagnosis. Five dogs historically had mast cell tumours and 21 dogs were not diagnosed with neoplasia prior, at the time of or after inflammatory myopathy diagnosis. Treatment included glucocorticoid monotherapy (n=12), cyclosporine monotherapy (n=1) or multiple immune-suppressive medications (n=14). Six dogs neurologically improved, 11 improved but relapsed while on treatment, seven did not improve. Eight dogs were euthanased, one died, four were lost to follow-up.

CLINICAL SIGNIFICANCE

Boxer dogs with non-infectious inflammatory myopathy can present for generalised weakness and dysphagia; long-term successful outcome is uncommon. The relationship between neoplasia and non-infectious inflammatory myopathy in boxer dogs remains unclear; future prospective studies evaluating a larger cohort are warranted.

A. R. ENS, Wada Y, Abdul Rahman Z, Ahmad S, Mohamud R, Mat Lazim N, Yean CY. Prevalence of Nasopharyngeal Carcinoma in Patients with Dermatomyositis: A Systematic Review and Meta-Analysis

Simple Summary

This first systematic review and meta-analysis on the prevalence of nasopharyngeal carcinoma in patients suffering dermatomyositis was necessitated by the absence of a true and reliable prevalence estimate necessary to adequately inform medical preparedness and decisions. Following a careful review of literature and data analyses, a prevalence of 3.3% was found. It is hoped that a clear knowledge of the actual prevalence of nasopharyngeal carcinoma in dermatomyositis patients would not only help sensitize clinicians and patients about the frequency of these disease conditions but would also enhance the adoption of precautions essential to mitigate their co-occurrence in patients.

Abstract

For more than 50 years, nasopharyngeal carcinoma (NPC) has been associated with dermatomyositis (DM), a rare idiopathic inflammatory disorder that mainly affects the skin and muscles. Although the association between these rare diseases is well-documented, the actual prevalence of NPC in DM patients remains unknown. Here, a systematic review and meta-analysis of published data was conducted in accordance with the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Electronic databases including PubMed, Scopus, ScienceDirect, and Google Scholar were searched without year or language restrictions for studies reporting the occurrence of NPC in DM patients. The study protocol was lodged with PROSPERO (CRD42021225335). A total of 95 studies covering 303 cases of NPC among 16,010 DM patients was included. Summary estimates were calculated using the random-effects model. The pooled prevalence of NPC in DM was 3.3% (95% CI, 2.5–4.3). When stratified according to study location, higher prevalence estimates were obtained for Hong Kong (36.5%), Malaysia (27.7%), and Singapore (11.9%). There was a predominance of cases among male DM patients compared with females, and most patients were aged 40 and above. Many of the NPC cases were found to be diagnosed after the diagnosis of DM. It is therefore pertinent to screen for NPC in DM patients, especially among older DM patients in the Asian region.

Autoimmune connective tissue diseases in the COVID-19 pandemic

Autoimmune connective tissue diseases are a heterogeneous group of clinical entities sharing a common feature-an impairment of structural components like collagen and elastin, arising by autoimmune mechanisms. Because most patients are on a long-term immunosuppressive therapy, which renders them vulnerable to infections, a new challenge appears in front of physicians in the coronavirus disease 2019 (COVID-19) era. Immune mechanisms are substantial for the control and ceasing of viral infections, and their impairment may cause serious complications; however, data from immunosuppressed transplant patients do not reveal a higher frequency or diseases' severity in those infected by COVID-19. Several immunotherapies used to treat autoimmune connective tissue diseases favorably modulate the immune response of severe acute respiratory syndrome coronavirus (SARS-CoV-2)-infected patients. The present review highlights the problems of susceptibility, severity, and therapeutic options in patients with autoimmune connective tissue diseases during the COVID-19 pandemic. The relationship between autoimmune connective tissue diseases and COVID-19 infection is explained with antiviral protection genes expression, hypercytokinemia, and lymphohistiocytosis/macrophage activation mechanisms. Recommendations concerning therapy for prevention during the pandemic period or in case of concomitant COVID-19 infection are also presented. Clinical trials are ongoing regarding COVID-19 therapy blocking the cytokine response. © 2021 Elsevier Inc. All rights reserved.

Risk factors for cancer-associated myositis: A large-scale multicenter cohort study

AIM

The aim of this study was to identify the risk factors and prognosis of patients with cancer-associated myositis (CAM).

METHOD

Four hundred and eighty-seven patients with dermatomyositis (DM), clinical amyopathic dermatomyositis (CADM) and polymyositis (PM) from 3 clinical centers were enrolled retrospectively in this study. Clinical and laboratory data of CAM and non-CAM patients were compared. Logistic regression analysis was used to identify risk factors of CAM.

RESULTS

Out of the 487 patients with DM/CADM/PM, 7.0% (34/487) of patients were classified as CAM. Older age (53.91 ± 13.32 vs. 48.76 ± 14.34 years), heliotrope rash (61.8% vs. 41.9%), shawl sign (41.2% vs. 22.1%), V sign (58.8% vs. 38.6%) were observed significantly more commonly in patients with CAM than those without CAM (all P < .05). Fever (17.7% vs. 37.8%), arthralgia/arthritis (23.5% vs. 45.7%), interstitial lung disease (ILD, 38.2% vs 68.9%) were significantly less common in the CAM group than the non-CAM group. Age at onset (odds ratio [OR] 1.036, 95% CI 1.001-1.072, P = .042), shawl sign (OR 2.748, 95% CI 1.107-6.822, P = .029), anti-transition initiation factor (TIF)-1γ antibody (OR 4.012, 95% CI 1.268-12.687, P = .018) were identified as the initial risk factors for the onset of CAM, and ILD was identified as a protective factor for CAM (OR 0.292, 95% CI 0.115-0.739, P = .009). All-cause mortality was significantly higher in CAM patients compared with non-CAM patients (P = .001).

CONCLUSION

The mortality of patients with CAM was higher than DM/CADM/PM patients without cancer. Malignancy should be screened in DM/CADM/PM patients especially with risk factors, including older age, shawl sign, anti-TIF-1γ antibody, and lack of ILD.

Evaluation of paraneoplastic antigens reveals TRIM21 autoantibodies as biomarker for early detection of ovarian cancer in combination with autoantibodies to NY-ESO-1 and TP53

BACKGROUND

The majority of ovarian cancer cases are diagnosed at an advanced stage with poor prognosis. This study evaluates autoantibodies against tumor antigens to identify candidate biomarkers for early detection of ovarian cancer in women at increased risk.

OBJECTIVE

To assess the immunoreactivity of paraneoplastic antigens and tumor associated antigens with high-grade serous ovarian cancer (HGSOC) samples.

METHODS

Five paraneoplastic antigens along with three tumor-associated antigens were evaluated with HGSOC patient serum samples. Validation screening was performed with n= 164 serum samples consisting of: 50 late stage HGSOC, 14 early stage HGSOC, 50 benign ovarian cyst, and 50 healthy control samples on ELISA and western blot. The four markers TRIM21, NY-ESO-1, TP53, and PAX8 were evaluated on a second validation serum set, n= 150.

RESULTS

TRIM21 achieved the highest sensitivity in the first validation screening of 33% with 100% specificity. Combining TRIM21 with NY-ESO-1, TP53, and PAX8 provided 67% sensitivity with 94% specificity, and 56% sensitivity at 98% specificity. These four markers resulted in 46% sensitivity with 98% specificity in the second validation cohort; TRIM21 achieved the highest individual sensitivity of 36%.

CONCLUSIONS

Autoantibodies to TRIM21, NY-ESO-1, and TP53 may complement CA125 in screening of women at genetic risk for ovarian cancer.

Malignancy in dermatomyositis: A retrospective paired case-control study of 202 patients from Central China

Dermatomyositis (DM) is an idiopathic inflammatory myopathy that is closely related to malignant diseases. Our study aims to investigate the incidence and predictive factors for occurrence of malignancy among DM patients from Central China.We performed a retrospective, paired, case-control study of 736 DM patients admitted to the First Affiliated Hospital of Zhengzhou University between 2010 and 2017. We paired the 65 patients with malignancy with age-matched and sex-matched patients without malignancy in a ratio of 1:2. Two hundred two patients were finally enrolled and their clinical and laboratory data were collected.The incidence of malignancy in DM patients was 8.83% (65/736). Most malignancies were detected in the most recent 1 year before (9/65, 13.85%) or within 3 years after (40/65, 61.54%) the onset of DM. Males (35/65, 53.85%) and patients aged between 50 and 69 years (43/65, 66.15%) were prone to develop malignancies. Lung cancer (n = 11, 31.43%) was the most common malignancy in male patients, while for females, thyroid, breast and cervical cancer (n = 4 each, 13.33%) were more prevalent. Adenocarcinoma and squamous cell carcinoma (both 18/65, 27.69%) were the top two most common pathological types. Univariate analysis demonstrated that Gottron's sign (P = .02), dysphagia (P = .04), albumin (ALB) reduction (P = .003), aspartate aminotransferase (AST, P = .03), creatine kinase-MB (P = .02), absence of fever (P = .02), arthralgia (P = .04) and interstitial lung disease (ILD, P = .05) were closely related to the occurrence of malignancy. Multivariate analysis revealed the independent risk factors of ALB reduction (odds ratio = 1.546, P = .04) and the protective factor of ILD (odds ratio = 0.349, P = .003). There was no significant difference in the follow-up period between patients with and without ILD (P = .38).ALB reduction and the absence of ILD were the risk factors for malignancy in DM patients. The protective mechanism of ILD for DM patients needs further study.

Retrospective Analysis of Cancer-Associated Myositis Patients over the Past 3 Decades in a Hungarian Myositis Cohort

Association between cancer and myositis has been extensively reported and malignancy is a potentially life-threating complication in myositis. In this retrospective study authors give an overview of Hungarian cancer-associated myositis (CAM) patients treated at a single centre managing 450 myositis patients. All patients were diagnosed according to Bohan and Peter. Statistical analysis of disease onset, age, sex, muscle, skin and extramuscular symptoms, muscle enzymes, presence of antibodies, treatment and prognosis was performed. 43 patients could be considered as having CAM. 83.72% had cancer within one year of diagnosis of myositis. Most common localizations were ductal carcinoma of breast and adenocarcinoma of lung. Significant differences were observed between CAM and the non-CAM control patients: DM:PM ratio was 2.31:1 vs. 0.87:1, respectively (p = 0.029), age at diagnosis was 56.60 ± 12.79 vs. 38.88 ± 10.88 years, respectively (p < 0.001). Tumour-treatment was the following: surgical removal in 55.81%, chemotherapy in 51.1%, radiotherapy in 39.53%, hormone treatment in 18.6%, combination therapy in 51.16% of patients. Muscle enzyme levels of patients undergoing surgery were significantly reduced after intervention. 36 patients died (83.72%); 25 DM (83.33%) and 11 PM patients (84.62%); 5 years survival was 15.4% for PM and 27.5% for DM. This study demonstrates that DM, distal muscle weakness, asymmetric Raynaud's phenomenon, older age, ANA-negativity are risk factors for developing malignancy and polymyositis patients have less chance of long-lasting survival. It is very important to think about cancer and follow every single myositis patient in the clinical routine because survival rate of CAM is very poor.

Predictive factors for sustained remission with stratification by myositis-specific autoantibodies in adult polymyositis/dermatomyositis

OBJECTIVE

The aim of this study was to clarify predictive factors for sustained remission in adult patients with PM/DM, particularly focusing on stratification by myositis-specific autoantibodies (MSAs).

METHODS

A total of 162 adult patients with PM/DM who were followed up for >1 year after diagnosis were retrospectively enrolled. MSAs were evaluated comprehensively in 102 patients whose sera were available. Sustained remission was defined as no evidence of disease activity (active skin rash, active myositis or active interstitial lung disease) for longer than a 6-month continuous period while undergoing myositis therapy or no medication. Clinical data were reviewed in patients' medical charts.

RESULTS

The sustained remission rate for all patients was 58% during the median follow-up period at 4 years. With regard to MSAs, the achievement rate of sustained remission among MSA-negative patients was significantly higher than that for patients with anti-aminoacyl-tRNA synthetase (P = 0.004), anti-melanoma differentiation-associated gene 5 (P = 0.037) or anti-transcriptional intermediary factor 1-γ (P = 0.013) antibodies. MSA-negative status (odds ratio 5.84, P = 0.009) and absence of severe muscle weakness requiring assistance at diagnosis (odds ratio 43.6, P < 0.001) were independent factors associated with sustained remission in multivariate analysis. Cumulative remission rates were significantly higher (P < 0.001) in patients with both the MSA-negative status and absence of severe muscle weakness at diagnosis than the others.

CONCLUSION

MSA-negative status and the absence of severe muscle weakness requiring assistance at diagnosis are independent predictive factors for sustained remission in adult PM/DM patients.

Anti-TIF1-γ autoantibodies: warning lights of a tumour autoantigen

Anti-transcription intermediary factor 1 (TIF1)-γ autoantibodies are robustly linked with cancer-associated DM in adults. This review aims to give an overview of the physiological context of TIF1-γ and to determine whether there is a pathophysiological link between anti-TIF1-γ autoantibodies and the occurrence of cancer. Detection of anti-TIF1-γ autoantibodies has a high sensitivity and specificity for cancer-associated DM in adults and is therefore useful for both diagnosis and cancer risk stratification. The function of the autoantigen, TIF1-γ, may provide insight into the mechanism behind this association. TIF1-γ is a ubiquitously present protein involved in various biological pathways, including TGF-β signalling. In cancer, it can act either as a tumour suppressor or promoter, depending on the cellular context and cancer stage. Evolving data provide pathophysiological insights, linking anti-TIF1-γ autoantibodies to both the anti-tumour response and to muscle and skin damage. TIF1-γ expression is increased in muscle and skin tissue of patients with DM. Mutations or loss-of-heterozygosity in TIF1-γ alleles in malignant tissue may result in the expression of tumour-specific neo-antigens stimulating autoantibody production. The newly formed autoantibodies are hypothesized to cross-react with antigens in muscle and skin, driving the development of DM. Based on the current evidence, anti-TIF1-γ autoantibodies should be considered warning lights of a potential tumour autoantigen and should alert the physician to the possibility of an underlying cancer.

Edematous myositis: a clinical presentation first suggesting dermatomyositis diagnosis

AIMS

Edema of the limbs is uncommon in idiopathic inflammatory myopathies (IIM). The few reported cases have been associated with severe and refractory dermatomyositis (DM), sometimes in association with cancers. We aimed to determine if edematous myositis is a homogeneous subtype based on clinical, serological and pathological features.

METHODS

This is a retrospective observational study performed between 2008 and 2015 in the French national referral center for myositis. All adult patients with an inflammatory muscle biopsy and upper limbs edema were included as well as IIM cases without limb edema as controls. Clinical, biological and pathological features were collected.

RESULTS

Seventeen edematous myositis were included and compared to 174 IIM without edema, including 50 DM controls. Edema was the first manifestation in 23% of patients. Muscle weakness was severe and symmetric, 71% of patients presented dysphagia and a restrictive ventilatory pattern was found in 40%. Fifty-two percent of patients had a typical DM skin rash and 23% had cancer within 3 years of diagnosing myositis. Fifty-three percent of patients presented a myositis specific antibody and only DM-specific antibodies were detected. Classic pathological DM features (perifascicular atrophy, perifascicular/perimysial perivascular inflammation) were uncommon but capillary C5b-9 deposition and MxA expression were seen in 79% and 73% of cases, respectively. A perimysial edema was found in 82% of cases. Seventeen percent of patients died (median follow up of 18 months). Edematous myositis demonstrated more marked capillary C5b-9 deposition compared to IIM controls. There was no clinical, biological or pathological difference with DM controls except for limb edema.

CONCLUSION

Our study underlines that limb edema could be a symptom of IIM and that edematous myositis are mostly DM. The vasculopathy seems to play a key role in its pathophysiology. Limb edema associated with muscle impairment should suggest the diagnosis of DM in clinical settings.

Analysis of myositis autoantibodies in Chinese patients with cancer-associated myositis

Background

Cancer‐associated myositis (CAM) has poor prognosis and causes higher mortality. In general, myositis‐specific autoantibodies (MSAs) and myositis‐associated autoantibodies (MAAs) have been shown to be useful biomarkers for its diagnosis.

Methods

In the present study, focus was given in assessing the presence, prevalence, and diagnostic values of myositis autoantibodies in Chinese patients diagnosed with CAM. The sera collected from 49 CAM patients, 108 dermatomyositis/polymyositis (DM/PM) patients without cancer, 105 disease controls, and 60 healthy controls were detected for the presence of 16 autoantigens (Jo‐1, OJ, EJ, PL‐7, PL‐12, MDA5, TIF1γ, Mi‐2α, Mi‐2β, SAE1, NXP2, SRP, Ku, PM‐Scl75, PM‐Scl100, and Ro‐52) using a commercial Euroline assay.

Results

The frequency of anti‐TIF1γ was significantly higher in CAM patients than in DM/PM patients without cancer (46.9% vs 14.8%, P < .001). Importantly, the sensitivity and specificity for this MSA were 46.9% and 85.2%, respectively. These helped to differentiate CAM patients from DM/PM patients without cancer. However, there was no difference in other MSAs and MAAs between CAM and DM/PM patients without cancer.

Conclusion

The present study indicates that anti‐TIF1γ levels can serve as important biomarkers for CAM diagnosis and help in distinguishing between CAM and DM/PM patients without cancer.

Inpatient burden and resource utilization of polymyositis and dermatomyositis: A 10-year Study of National Inpatient Sample

OBJECTIVES

To characterize inpatient prevalence and resource utilization of patients with polymyositis (PM) and dermatomyositis (DM).

METHODS

Patients with PM/DM were identified from the Nationwide Inpatient Sample (NIS) database from the year 2005 to 2014 using ICD-9 diagnostic codes. The primary outcome of this study was inpatient prevalence of PM/DM in the United States across the span of 10 years. Secondary outcomes included reason for hospitalization, inpatient mortality, morbidity, hospital length of stay (LOS), utilization of specialized procedures/tests and expenditures. A cohort of patients without PM/DM was also identified from the same database to serve as comparators. Multivariate regression analysis was used to adjust for age, sex, ethnicity, comorbidities and hospital characteristics.

RESULTS

A total of 160,528 admissions of patients with a diagnosis of PM/DM occurred in the study period, corresponding to the inpatient prevalence of 41.9 cases per 100,000 discharges. During admission, patients with PM/DM died more frequently than patients without PM/DM with an adjusted odds ratio (aOR) of 2.22 (P<0.01). A significantly higher inpatient morbidity among patients with PM/DM was also observed as indicated by a significantly higher risk of shock (aOR 2.33; P<0.01), acute kidney injury (aOR 1.12; P<0.01), multi-organ failure (aOR 1.83; P<0.01) and need for admission to intensive care unit (aOR 1.94; P<0.01). Patients in the PM/DM had an average of 1.7 more days of LOS (P<0.01). The mean hospital costs and total hospitalization charges for patients with PM/DM were significantly higher than patients without PM/DM with additional adjusted mean of $4,217 and $13,531, respectively, in the multivariate model. Patients with PM/DM underwent computerized tomography scan (aOR 1.90; P<0.01), magnetic resonance imaging (aOR 1.68; P<0.01) and angiography (aOR 1.15; P<0.01) more often than comparators.

CONCLUSIONS

Inpatient prevalence of PM/DM was higher than what would be expected from the overall incidence. Hospitalizations of patients with PM/DM were associated with significantly higher rate of mortality, morbidity and resource utilization.

Recognition and Management of Myositis-Associated Rapidly Progressive Interstitial Lung Disease

Idiopathic inflammatory myopathies are autoimmune processes that are characterized by skeletal muscle inflammation. The lung is the most commonly involved extramuscular organ, and, when present, pulmonary disease drives morbidity and mortality. A subset of patients can present with rapidly progressive hypoxemic respiratory failure due to myositis-related interstitial lung disease. Confirmatory autoantibody testing requires sending samples to a reference laboratory; thus, diagnosis of rapidly progressive myositis-associated interstitial lung disease relies on a high index of suspicion and careful history and physical examination. Although the cornerstone of therapy for these patients remains multimodality immunosuppression, emerging data support a role for advanced therapies (including extracorporeal membrane oxygenation and lung transplantation) in appropriately selected patients. It is hoped that greater awareness of the clinical features of this syndrome will allow for appropriate diagnosis and treatment of these potentially treatable patients, as well as raise awareness of the need for multicenter collaboration to prospectively study how to manage this complex disease.

A 21-Year-Old Woman with Joint Pain and Skin Ulceration

The illness started with pain and stiffness in her bilateral hands and wrists four months prior, with progression to bilateral elbows, knees, and ankles. The pain and stiffness were worse in the morning and limited her ability to use her hands or walk comfortably. She also noted swelling of her hands, knees, and ankles. The pain and swelling improved slightly with ibuprofen. She also noted increased fatigue, alopecia, decreased appetite, and nausea. She went to urgent care one month earlier and a physician prescribed ibuprofen and obtained initial serologies.

18F-FDG PET/CT in a Patient With Thymoma-Associated Paraneoplastic Polymyositis

A 43-year-old woman presented with progressive muscle weakness and myalgia for 1 month. Laboratory tests revealed the elevation of myogenic enzymes. MRI of the thighs demonstrated a pattern of edema for inflammatory myopathy. Electromyography showed diffuse myopathic disorder, and muscle biopsy indicated polymyositis. F-FDG PET/CT was performed to investigate the potential paraneoplastic syndrome and revealed a soft tissue lesion with F-FDG avidity in the right anterior mediastinum, as well as diffusely increased activity throughout the body muscles. The patient's symptoms and biochemical abnormalities were gradually relieved after the tumor resection, and the histopathology indicated a type AB thymoma.

Peculiar clinicopathological features of immune-mediated necrotizing myopathies

PURPOSE OF REVIEW

In the past decade, immune-mediated necrotizing myopathies have emerged as a separate entity in the heterogenous group of autoimmune myopathies. This group is characterized by clinical manifestations restricted to the muscle tissue, and until recently, the definition was based on muscular pathological features.

RECENT FINDINGS

It was shown that they are the most severe autoimmune myopathies in term of muscle damages. They have been associated with two myositis-specific antibodies: either anti-signal recognition particle (anti-SRP) or anti-hydroxy-3-methylglutaryl-CoA reductase (anti-HMGCR) antibodies. These two antibodies are now considered as immune-mediated necrotizing myopathy (IMNM) diagnostic criteria. Each antibody delineates a homogenous subgroup of IMNM patients in terms of severity and IMNM without myositis-specific antibodies have a high risk of malignancy. In addition, pathological observations as well as in-vitro experiments suggest the pathogenic role of anti-SRP and anti-HMGCR antibodies.

SUMMARY

IMNM are muscle-specific autoimmune diseases associated with a severe weakness and a risk poor muscle strength recovery. Anti-SRP and anti-HMGCR antibodies are specifically associated with this condition and are crucial for the diagnosis and the prognosis. The muscle biopsy remains necessary for IMNM diagnosis in absence of myositis-specific antibodies.

How to investigate: Suspected systemic rheumatic diseases in patients presenting with muscle complaints

Muscular symptoms, which may be due to multiple causes, are one of the most common early complaints in a rheumatology practice. Musculoskeletal symptoms in rheumatic conditions are very varied, ranging from mechanical problems to muscular symptoms derived from inflammatory and systemic autoimmune diseases. Several drugs commonly used by different specialists and certain drugs used in rheumatology can also cause a wide variety of muscle symptoms. A description of different systemic autoimmune diseases follows to describe the different forms of involvement of the musculoskeletal system that they cause, as well as the main causes with which a differential diagnosis should be made. In this chapter, we will try to give some clues to reach an early diagnosis using clinical criteria, particularly based on a directed anamnesis and physical examination, discussing possible guidelines for the complimentary tests that may be required in patients with muscle complaints.

[Recognize rare diseases on the skin]

The correct interpretation of skin manifestations can facilitate the diagnosis of many rare systemic diseases. Such manifestations can be due to autoimmune diseases (e.g. dermatomyositis, systemic lupus erythematosus, systemic sclerosis and sarcoidosis) and metabolic diseases (e.g. Anderson-Fabry disease and porphyria cutanea tarda). Other cutaneous symptoms are of great importance because they are possible warning signs of occult diseases of internal organs. This is true for example for some diseases from the group of neutrophilic dermatoses, such as Sweet's syndrome and pyoderma gangraenosum.

Paraneoplastic syndromes in lung cancer and their management

Paraneoplastic syndromes are most frequently associated with lung cancer. This review considers a variety of paraneoplastic syndromes associated with lung cancer and discusses their pathophysiology, clinical features and management options.

Diagnostic potential of sarcoplasmic myxovirus resistance protein A expression in subsets of dermatomyositis

AIMS

To elucidate the diagnostic value of sarcoplasmic expression of myxovirus resistance protein A (MxA) for dermatomyositis (DM) specifically analysing different DM subforms, and to test the superiority of MxA to other markers.

METHODS

Immunohistochemistry for MxA and retinoic acid-inducible gene I (RIG-I) was performed on skeletal muscle samples and compared with the item presence of perifascicular atrophy (PFA) in 57 DM patients with anti-Mi-2 (n = 6), -transcription intermediary factor 1 gamma (n = 10), -nuclear matrix protein 2 (n = 13), -melanoma differentiation-associated gene 5 (MDA5) (n = 10) or -small ubiquitin-like modifier activating enzyme (n = 1) autoantibodies and with no detectable autoantibody (n = 17). Among the patients, nine suffered from cancer and 22 were juvenile-onset type. Disease controls included antisynthetase syndrome (ASS)-associated myositis (n = 30), immune-mediated necrotizing myopathy (n = 9) and inclusion body myositis (n = 5).

RESULTS

Sarcoplasmic MxA expression featured 77% sensitivity and 100% specificity for overall DM patients, while RIG-I staining and PFA reached respectively 14% and 59% sensitivity and 100% and 86% specificity. In any subset of DM, sarcoplasmic MxA expression showed higher sensitivity than RIG-I and PFA. Some anti-MDA5 antibody-positive DM samples distinctively showed a scattered staining pattern of MxA. No ASS samples had sarcoplasmic MxA expression even though six patients had DM skin rash.

CONCLUSIONS

Sarcoplasmic MxA expression is more sensitive than PFA and RIG-I expression for a pathological diagnosis of DM, regardless of the autoantibody-related subgroup. In light of its high sensitivity and specificity, it may be considered a pathological hallmark of DM per se. Also, lack of MxA expression in ASS supports the idea that ASS is a distinct entity from DM.