Myositis-specific autoantibodies and their clinical associations in idiopathic inflammatory myopathies

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

Background

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

Case Presentation

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

Results

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

Conclusion

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

Paraneoplastic myopathies

This chapter reviews the association between cancer and the idiopathic inflammatory myopathies (IIM), which includes dermatomyositis (DM), antisynthetase syndrome (ASyS), immune-mediated necrotizing myopathy (IMNM), and inclusion body myositis (IBM). Accumulating evidence shows that the risk of a coexisting malignancy is high in patients with DM, especially among those with anti-Tif1γ autoantibodies. Patients with IMNM and no defined autoantibodies also have an increased risk of malignancy. Recent evidence demonstrates that many IBM patients have increased numbers of circulating CD57+ CD8+ T cells, consistent with a diagnosis of large granular lymphocytic leukemia. In contrast, IMNM patients with anti-SRP or anti-HMGCR autoantibodies as well as patients with ASyS syndrome do not have a definitively increased risk of cancer. Patients who have a cancer treated with one of the immune checkpoint inhibitors can develop myositis (ICI-myositis), sometimes along with myasthenia gravis and/or myocarditis.

Age distribution and prevalence in different age groups of four myositis-specific autoantibodies, including anti-ARS, anti-MDA5, anti-Mi-2, and anti-TIF1γ antibodies

We accumulated the demographic information and analyzed the prevalence of myositis-specific antibodies (MSAs) in a large cohort across Japan as standard testing for MSAs becomes more widely available. This retrospective, observational, cohort study analyzed the records of individuals aged 0-99 years who are tested for serum MSAs at SRL Incorporation from January 2014 to April 2020 across Japan. An enzyme-linked immunosorbent assay testing was applied to determine the presence of anti-aminoacyl tRNA synthetase (anti-ARS), anti-Mi-2, anti-melanoma differentiation-associated gene 5 (anti-MDA5), or anti-transcriptional intermediary factor 1-γ (anti-TIF1γ) (Medical and Biological Laboratories). Anti-TIF1γ antibody was detected more in male patients than female patients. In contrast, women were predominant in patients with other MSAs. More than half of the anti-ARS or anti-TIF1γ antibody-positive patients were over 60 years old, although anti-MDA5 or anti-Mi-2-positive patients were mostly under <60 years old. Anti-MDA5 antibody-positive patients were mostly aged 40-59 years, while other MSA groups were mostly 60-79 years. Anti-MDA5 antibody was detected most frequently in the age range of 0-29 years. Anti-TIF1γ antibody was the second most commonly detected autoantibody in the age range of 0-19 years. Anti-ARS antibody was the most frequently detected autoantibody after the age of 30 years, and the frequency of anti-ARS gradually increased at more advanced ages. The second and third most detected autoantibodies were anti-MDA5 and anti-TIF1γ, respectively, in ages 30-79 years. We performed a nationwide >3-year evaluation of MSA detection in a routine diagnostic setting. This paper provides clinical images concerning the relationship between four MSA types and the distribution of sex and age in a large population.

Lung transplantation for anti-MDA5-positive dermatomyositis-associated rapid progressive interstitial lung disease: report of two cases and review of the literature

Lung transplantation is an ultimate lifesaving treatment for many patients with end-stage lung disease, whereas whether it is an optional intervention for the anti-melanoma differentiation-associated gene 5 (anti-MDA5)-positive dermatomyositis (DM)-associated rapid progressive interstitial lung disease (RP-ILD) remain controversial. We report two patients diagnosed with anti-MDA5-positive DM-associated RP-ILD, who were both bridging to lung transplant with extracorporeal membrane oxygenation (ECMO) after failing to respond to extensive immunosuppressants. The first patient received full rehabilitation, but the second patient died of DM flare at the early-stage post-lung transplantation. Most of the clinical information was parallel in these two patients except the anti-MDA5 antibody level, which gradually decreased and became negative in the first patient but always hovering in high titers in the second patient, although both of the two patients received standard immunosuppressive regimen for prevention of rejection after lung transplantation. A total of 11 patients with anti-MDA5-positive DM-associated RP-ILD who underwent lung transplantation from the literature were identified. Most patients (10/11, 90.1%) were successfully discharged and without DM flare during the follow-up period post-lung transplantation. Nine of them were followed up more than 1 year, and anti-MDA-5 antibody was reported to be negative in four patients, whereas the others were unavailable. Combined with the case series in the literature, our limited experience suggests that lung transplantation is a promising therapeutic option for end-stage patients with anti-MDA5-positive DM-associated RP-ILD, with ECMO as a bridge to lung transplantation, if necessary. However, clearance or a downtrend of anti-MDA5 antibody may be required pre-transplant to avoid DM flare and recurrent RP-ILD post-transplantation.

Predictors of progression in idiopathic inflammatory myopathies with interstitial lung disease

The idiopathic inflammatory myopathies (IIMs) are a group of connective tissue diseases that afect multiple organ systems, including the lungs. Interstitial lung disease (ILD) is the most common and heterogeneous complication of IIMs, with its degree ranging from mild to fatal. Thus, it is critical to identify clinical features and validated biomarkers for predicting disease progression and prognosis, which could be beneficial for therapy adjustment. In this review, we discuss predictors for rapid progression of IIM-ILD and propose guidance for disease monitoring and implications of therapy. Systematic screening of myositis-specific antibodies, measuring serum biomarker levels, pulmonary function tests, and chest high-resolution computer tomography will be beneficial for the evaluation of disease progression and prognosis.

Profile of specific and associated autoantibodies in patients with idiopathic inflammatory myopathies in a Colombian population

Objectives

Idiopathic inflammatory myopathies (IIMs) are chronic, autoimmune diseases with several forms of presentation. Diagnosis is mostly clinical in our region. Our aim was to evaluate the autoantibody profile of patients with IIMs.

Methods

This study is a cross-sectional study with a prospective recollection of data, conducted between 2019–2021, in a single center in Cali, Colombia. Patients with a clinical diagnosis or suspicion of IIM were included. The presence of myositis-specific/associated antibodies was evaluated by immunoblotting in serum samples. Phenotypic characterization was performed.

Results

A total of 36 patients were included. The mean age was 50.6 (16.7) years, and 20 (55.6%) were female. Eighteen (50%) patients were seropositive, of which 11 (30.5%) presented one positive antibody, with anti-TIF1ɣbeing the most frequent (n = 4, 11.1%), followed by anti-Ro52 (n = 2, 5.6%). Seven patients (19.4%) showed >1 positive antibody. Dermatomyositis was the most frequent type of IIM in seropositive patients (n = 8, 44.4%), followed by anti-synthetase syndrome (n = 4, 22.2%). Weakness was symmetric and presented in the upper and lower extremities in 11 (61.1%) patients each. Both respiratory insufficiency and weight loss were seen in 7 (38.9%) patients, Gottron papules in six (33.3%) patients, and heliotrope rash, esophageal dysmotility, and myalgia in 5 (27.8%) patients. Pulmonary interstitial disease was seen in 4 (22.2%, with antibodies for anti-Ro52, anti-MDA5 + anti-Jo1 + anti-TIF1ɣ, anti-MDA5 + anti-SAE1 + anti-NXP2, and anti-cN1A + anti-Ro52) patients, and malignancy was seen in 2 (11.1%) patients (1 with anti-Mi2β and 1 with anti-TIF1ɣ + anti-Mi2α). In all, 7 (19.4%) patients required intensive care (2 seropositive, 1 with anti-PL7, 1 with anti-MDA5 + anti-Jo1 + anti-TIF1ɣ), and 1 (2.8%) (seronegative) patient died.

Conclusion

This study is the first study in the Southwest of Colombia that evaluates myositis-specific/associated antibodies in IIM. Half of the patients were seropositive. Anti-TIF1ɣwas the most frequent MSA and anti-Ro52 was the most frequent MAA. Several patients presented antibody combinations. Further studies are needed to fully associate phenotypes with antibodies.

Myositis-specific autoantibodies and their clinical associations in idiopathic inflammatory myopathies: results from a cohort from China

OBJECTIVES

The purpose of this study was to determine the incidence of myositis-specific autoantibodies (MSAs) in a cohort of Chinese patients with idiopathic inflammatory myopathies (IIMs) and to examine their associations with clinical characteristics and long-term prognosis.

METHODS

Adult patients with confirmed IIMs (n = 515) were studied using the EUROLINE Autoimmune Inflammatory Myopathies 16 Ag (IgG) commercial line blot test to detect MSAs/myositis-associated autoantibodies. We collected the laboratory data and clinical features. The frequencies of MSAs and their associations with clinical phenotypes were evaluated using SPSS 25.0 software.

RESULTS

At least one MSA was found in 88.2% of the 515 IIM patients studied. The most frequently detected MSAs were anti-MDA5 (25.4%), anti-Jo-1(15.1%), and anti-EJ (9.5%). Autoantibodies against MDA5, TIF1-γ, and NXP2 were significantly correlated with cutaneous involvement (P < 0.001 or P < 0.01). Anti-TIF1-γ-positive patients had an enhanced risk of malignancy (OR = 3.51). Rapidly progressive interstitial lung disease (RP-ILD) was significantly correlated with anti-MDA5 (P < 0.0001). Anti-MDA5-positive patients had increased risks of elevated ferritin and decreased lymphocyte counts (OR = 5.65 and OR = 5.74, respectively). Kaplan-Meier survival revealed that individuals positive for anti-MDA5, especially anti-MDA5 combined with anti-Ro52, had the worst prognosis (P = 0.03). Male, old age, RP-ILD, and elevated ferritin were identified as predictors of poor prognosis in IIM patients.

CONCLUSIONS

MSAs were present in the majority of the IIM patients. Numerous MSAs were independent factors for identifying exceptional clinical phenotypes. Key Points • This is a large Chinese cohort of IIM patients to analyze possible associations of MSA profiles with clinical characteristics, aiming to provide valuable data for clinical work. • MSAs were present in approximately 90% of IIM patients with distinct clinical subsets. Patients with anti-Jo-1 and non-anti-Jo-1 ASAs exhibited similar characteristics. • The association of anti-TIF1-γ with malignancy was confirmed in adult patients. Patients with IIMs who were positive for both anti-Ro52 and anti-MDA5 had a worse prognosis. • Male, RP-ILD, and heliotrope rash were independent risk factors for a poor prognosis in patients with IIMs.

Performance of the 2017 EULAR/ACR classification criteria in anti-MDA5 associated idiopathic inflammatory myopathy

OBJECTIVE

To evaluate the performance of the 2017 EULAR/ACR classification criteria in a cohort of anti-MDA5 associated IIM patients.

METHODOLOGY

Consecutive adult patients with a clinical diagnosis of anti-MDA5 associated IIM from 10 hospitals in Hong Kong were recruited retrospectively. Clinical characteristics were collected by reviewing the electronic medical records. A commercial line-blot immunoassay was used to detect the myositis specific antibodies (MSA). Performance of the 2017 EULAR/ACR classification criteria was examined. Incorporation of the anti-MDA5 antibody in the EULAR/ACR criteria and the MSA-based criteria recently proposed by Casal-Dominguez et al. were also evaluated. Lastly, a new set of phenotypic-serological classification criteria specific for anti-MDA5 was proposed.

RESULTS

A hundred and twenty patients with anti-MDA5 associated IIM were recruited. The subgroups were exclusively DM (31.7%) and CADM (68.3%). Eight-six (71.7%) and 49 (40.8%) patients fulfilled the EULAR/ACR classification criteria and the Bohan/Peter criteria respectively. With the addition of Sontheimer's criteria for CADM, 76.7% the patients could be classified by the Bohan and Peter criteria. The sensitivity of the EULAR/ACR criteria could be improved to 98.3% if anti-MDA5 antibody was considered one of the criteria. The criteria by Casal-Dominguez et al. had 100% sensitivity in this cohort. Our newly proposed criteria for "anti-MDA5 syndrome" could also classify 97.5% of the patients.

CONCLUSIONS

Almost 30% of patients with clinical anti-MDA5 associated IIM could not be classified by the EULAR/ACR criteria. Modification of the existing criteria incorporating anti-MDA5 antibody or development of a new specific set of criteria for "anti-MDA5 syndrome" are suggested.

Predictors of rapidly progressive- interstitial lung disease and mortality in patients with autoantibodies against melanoma differentiation-associated protein 5 dermatomyositis

Objective

Anti-melanoma differentiation-associated protein 5 (MDA5) positive dermatomyositis (DM) is associated with rapidly progressive interstitial lung disease (RP-ILD) and high mortality. This multicentre retrospective study aimed to identify predictors for mortality and RP-ILD.

Methods

Anti-MDA5 positive DM patients were identified from the Hong Kong Myositis Registry and the Clinical Data Analysis and Reporting System. Clinical characteristics were reviewed. Risk factors for mortality and RP-ILD were identified.

Results

Among the 116 recruited patients, 100 (86.2%) had ILD, 47 (40.5%) had RP-ILD and 44 (37.9%) patients died. Cox regression analysis revealed that RP-ILD (HR 9.735, 95%CI 3.905–24.272), age &gt;52 (HR 4.750, 95%CI 1.692–13.333), ferritin level &gt;2800pmol/l (HR 3.042, 95%CI 1.323–6.997) and lactate dehydrogenase (LDH) &gt;400 IU/l (HR 2.290, 95% CI 1.009–5.198) were independent predictors of mortality. With regard to RP-ILD, analyses showed that potential predictors at baseline included age &gt;50 years old (HR 2.640, 95%CI 1.277–5.455), LDH &gt;300IU/l (HR3.189, 95%CI 1.469–6.918), fever (HR 1.903, 95% CI: 0.956–3.790) and neutrophil to lymphocyte ratio (NLR) &gt;7.0 (HR 1.967, 95%CI 0.942–4.107). We proposed a prediction model, based on Fever, LDH, Age and White cell count (“FLAW”), to stratify risk of development of RP-ILD. The probability of RP-ILD in a patient with a score of 4 was 100%. A small internal validation cohort showed the odds of RP-ILD with FLAW scores of 0, 1, 2 and 3 were 0%, 0%, 42.9% and 75% respectively.

Conclusions

Anti-MDA5-associated RP-ILD is significantly associated with poor survival rates. The “FLAW” model maybe useful to predict the development of RP-ILD.

Seasonal Effect on Disease Onset and Presentation in Anti-MDA5 Positive Dermatomyositis

Objective

To investigate the seasonal variation of disease onset and presentation in an ethno-geographically homogeneous cohort of patients with anti-MDA5 positive dermatomyositis (DM).

Methods

This was a multi-centered, retrospective cohort study. Adult Chinese anti-MDA5 positive DM patients were identified from the Hong Kong Myositis Registry and the Clinical Data Analysis and Reporting System from 2015 to 2020. Equal number of IIM patients without anti-MDA5 antibody were selected as controls. Line blot immunoassay was used to detect the autoantibodies. The onset of disease, presenting clinical features and subsequent complications were analyzed for any seasonality.

Results

A total of 110 patients with anti-MDA5 positive DM were studied. The mean age at diagnosis was 53.0 ± 12.3 years and the mean follow-up duration was 20.6 ± 23.1 months. Two third of the patients (66%) had the clinically amyopathic phenotype. Most patients (86%) had interstitial lung disease (ILD) and 42% developed rapidly progressive ILD (RP-ILD). The mortality was 40% and the commonest cause was RP-ILD. Chi-square test showed significantly less patients had symptom onset in July to September. However, no particular seasonal pattern was observed in the anti-MDA5 negative IIM controls. RP-ILD occurred more frequently in patients with disease onset in October to December. Anti-MDA5 positive DM patients with disease onset in warmer months (April to September) were more likely to have clinical muscle involvement.

Conclusion

Apparent seasonal patterns were noted in our ethno-geographically identical anti-MDA5 positive DM patients, but not in IIM patients in general. Certain environmental factors, particularly infection, might be implicated.

Rheumatic Manifestations and Diseases From Immune Checkpoint Inhibitors in Cancer Immunotherapy

Immune checkpoint inhibitors (ICIs), which can enhance antitumor immunity and inhibit cancer growth, have revolutionized the treatment of multiple cancers and dramatically decreased mortality. However, treatment with ICIs is directly associated with immune-related adverse events (irAEs) because of inflammation in off-target organs and autoimmunity resulting from non-specific immune activation. These irAEs can cause rheumatic diseases and manifestations such as inflammatory arthritis, polymyalgia rheumatica, myositis, vasculitis, Sicca and Sjogen's syndrome, and systemic lupus erythematosus. Early diagnosis and treatment of these adverse events will improve outcomes and quality of life for cancer patients. The treatment of rheumatic diseases induced by ICIs requires multidisciplinary cooperation among physicians. Furthermore, the underlying mechanisms are not fully understood and it is difficult to predict and evaluate these side effects precisely. In this review, we summarize available studies and findings about rheumatic irAEs, focusing mainly on the clinical manifestations, epidemiology, possible mechanisms, and guiding principles for treating these irAEs.

Clinical features and diagnostic tools in idiopathic inflammatory myopathies

Idiopathic inflammatory myopathies (IIMs) are rare autoimmune disorders affecting primarily muscles, but other organs can be involved. This review describes the clinical features, diagnosis and treatment for IIMs, namely polymyositis (PM), dermatomyositis (DM), sporadic inclusion body myositis (sIBM), immune-mediated necrotizing myopathy (IMNM), and myositis associated with antisynthetase syndrome (ASS). The diagnostic approach has been updated recently based on the discovery of circulating autoantibodies, which has enhanced the management of patients. Currently, validated classification criteria for IIMs allow clinical studies with well-defined sets of patients but diagnostic criteria to guide the care of individual patients in routine clinical practice are still missing. This review analyzes the clinical manifestations and laboratory findings of IIMs, discusses the efficiency of modern and standard methods employed in their workup, and delineates optimal practice for clinical care. Α multidisciplinary diagnostic approach that combines clinical, neurologic and rheumatologic examination, evaluation of electrophysiologic and morphologic muscle characteristics, and assessment of autoantibody immunoassays has been determined to be the preferred approach for effective management of patients with suspected IIMs.