Evaluation and validation of the prognostic value of anti-MDA5 IgG subclasses in dermatomyositis-associated interstitial lung disease

Clinical features of flare in Japanese patients with new-onset SLE and risk factors for SLE flare in daily clinical practice: a single-center cohort study

This study aimed to elucidate the clinical features, outcomes and risk factors of flares in patients with systemic lupus erythematosus (SLE). Data were collected from patients with newly diagnosed SLE at the Fukushima Medical University Hospital between 2011 and 2022. Patients who experienced a flare during the study period constituted the flare group, and their clinical features were compared with those of the no-flare group. The cumulative flare-free survival regarding several clinical items was compared between the two groups using Kaplan-Meier's curves. Among 387 patients with SLE, 83 patients with newly diagnosed SLE were included. Their mean age was 37.9 years, and 29 patients experienced flares during the study period. The general characteristics were similar between the two groups, with the exception of the observation period and anti-SS-A antibody positivity. Regarding therapy, a significantly increased frequency of hydroxychloroquine intake and combination with immunosuppressive agents were observed in the no-flare group. The Kaplan-Meier analysis revealed a significantly higher cumulative flare-free survival in the anti-SS-A negative group and combination immunosuppressive therapy group. In conclusion, anti-SS-A positivity may be a risk factor for SLE flare. In turn, combination immunosuppressive therapy may be beneficial for SLE treatment in daily clinical practice.

Anti-MDA5 antibody-positive dermatomyositis: pathogenesis and clinical progress

Anti-melanoma differentiation-associated protein 5 (MDA5) antibody-positive dermatomyositis (MDA5-DM) is a subtype of dermatomyositis. Although the aetiology and pathology remain unclear, increasing evidence suggests that viral infection is a potential trigger of MDA5-DM. Multiple factors, including T cells, B cells, neutrophils and macrophages, are implicated in the pathophysiology of MDA5-DM. Distinctive skin rashes, rapidly progressive interstitial lung disease, peripheral lymphopenia and elevated serum ferritin levels are the most prominent clinical and laboratory features of MDA5-DM. Concomitant infection is a common complication of MDA5-DM. The proper evaluation of patients with MDA5-DM requires knowledge of the disease heterogeneity and clinical course variability. Several biomarkers, including serum levels of anti-MDA5 antibodies and biomarkers related to macrophage activation, have been identified as useful tools for monitoring disease activity and prognosis. MDA5-DM shows a poor response to conventional glucocorticoid and immunosuppressant therapy and has a poor overall prognosis. Therefore, there is an urgent need to explore the key pathogenic mechanisms of MDA5-DM and develop novel therapeutic options for patients. This Review discusses recent clinical progress and pathogenic findings of MDA5-DM.

Transcriptomic profiling and longitudinal study reveal the relationship of anti-MDA5 titer and type I IFN signature in MDA5+ dermatomyositis

Objective

This study aimed to investigate the relationship between anti-MDA5 titer and type I IFN signature in patients with MDA5+ DM.

Methods

We explored the transcriptome profiling of PBMCs in MDA5+ DM patients with high-titer of antibody at disease onset or relapse and normal low-titer after treatment and healthy donors. Subsequently, we revealed the dynamic relationship between serum type I IFN scores and antibody titers.

Result

Differentially expressed genes in MDA5+ DM patients were enriched for related pathways and biological functions linked to viruses and cytokines compared to healthy donors. Similar differences remained pooled between the high-titer and low-titer group, and type I-specific interferon response genes showed upregulation in high-titer group. Significant correlations were found between anti-MDA5 titers and type I IFN scores (r = 0.50, P< 0.001). Contemporaneous anti-MDA5 titers revealed to be significantly higher in the group with ultra-high type I IFN scores (vs. high group, P = 0.027; vs. low group, P< 0.001). Longitudinal assessment of type I IFN scores and anti-MDA5 titers, including pre- and post-treatment changes at initial diagnosis and dynamic changes during treatment, presented an asynchrony between the two parameters in response to treatment.

Conclusion

Anti-MDA5 antibody titers correlated with type I IFN signature in patients with MDA5+ DM and they both changed dynamically but not synchronously over the course of treatment.

Ground-glass opacity score predicts the prognosis of anti-MDA5 positive dermatomyositis: a single-centre cohort study

OBJECTIVE

Dermatomyositis (DM) positive with anti-melanoma differentiation-associated gene 5 (anti-MDA5-DM) is a systemic autoimmune disease with high mortality. This study aimed to explore the risk factors of death in anti-MDA5-DM and validate a prediction model for all-cause mortality in anti-MDA5-DM.

METHOD

We conducted a retrospective study using a single-centre cohort of patients with newly onset anti-MDA5-DM from June 1, 2018 to August 31, 2021. Patients were divided into four groups according to baseline ground-glass opacity (GGO) score: Group A, GGO ≤ 1; Group B, 1 < GGO ≤ 2; Group C, 2 < GGO ≤ 3; Group D, GGO > 3. The primary outcome was death during the follow-up. Secondary outcomes included death within 3, 6, 12 months, severe infection, and remission during the first 12 months.

RESULTS

A total of 200 patients were included in the study. Based on multivariable Cox regression, the prognostic factors at baseline were identified as CRP > 5 mg/L, serum ferritin (SF) > 600ng/ml, positive anti-Ro52 antibody, prophylactic use of compound sulfamethoxazole (SMZ Co), four-category GGO score: GGO ≤ 1, 1 < GGO ≤ 2, 2 < GGO ≤ 3, GGO > 3. The final mortality of four groups was 16.4, 22.2, 48.5, 92.0%, respectively. Compared with Group A, the Hazards Ratio (HR) of Group B was 1.408, (p = 0.408), HR of Group C was 3.433 (p = 0.005), HR of Group D was 4.376 (p = 0.001).

CONCLUSIONS

GGO score is a reliable predictor for risk stratification in anti-MDA5-DM and may provide guidance for individualized managements of patients.

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.

Prognosis of spontaneous pneumomediastinum occurring in dermatomyositis or polymyositis patients with interstitial lung disease according to antimelanoma differentiation-associated gene 5 antibody status: a retrospective cohort study

OBJECTIVES

Spontaneous pneumomediastinum (SPNM) historically has been considered a poor prognostic factor in dermatomyositis/polymyositis patients complicated with interstitial lung disease (ILD). However, there is a lack of actual data regarding the association between SPNM occurrence and mortality in dermatomyositis/polymyositis patients. This study aimed to assess the association between SPNM occurrence and mortality in myositis patients with ILD according to antimelanoma differentiation-associated gene 5 (MDA5) antibody status.

METHODS

Dermatomyositis/polymyositis patients with ILD who were hospitalised at five Japanese hospitals from 2016 to 2020 were included in this retrospective observational study. We collected data about baseline characteristics including myositis-specific autoantibodies, treatments, SPNM and death within 1 year from therapy initiation or strengthening. Baseline characteristics and outcomes were compared between patients with and without SPNM (the SPNM group and the non-SPNM group, respectively).

RESULTS

A total of 119 patients were analysed. SPNM occurred in 23 patients, and 15 patients died. Fifteen patients with SPNM were anti-MDA5 antibody positive. The mortality rate was significantly higher in the SPNM group (34.8%) than in the non-SPNM group (7.3%) (p=0.001). All deaths in the SPNM group occurred in anti-MDA5 antibody-positive patients (8/15), whereas none of the anti-MDA5 antibody-negative patients in the SPNM group died (0/8). In anti-MDA5 antibody-positive patients, the mortality rate was significantly higher in patients with SPNM occurrence (53.3%) than in those without SPNM occurrence (4.0%) (p=0.001).

CONCLUSION

SPNM occurred more frequently in anti-MDA5 antibody-positive than in anti-MDA5 antibody-negative myositis patients. SPNM occurrence was associated with higher mortality risk, especially in anti-MDA5 antibody-positive patients.

Anti-MDA5 dermatomyositis: an update from bench to bedside

PURPOSE OF REVIEW

This review summarizes the recent developments about anti-MDA5 antibody positive dermatomyositis with a focus on its pathogenesis, clinical features and treatment options of rapidly progressive interstitial lung disease, its most ominous complication.

RECENT FINDINGS

Anti-MDA5+ dermatomyositis has a heterogeneous clinical spectrum with different patient subsets exhibiting widely different outcomes; severe acute interstitial lung disease is the main factor impacting prognosis. The pathogenetic role of anti-MDA5 antibodies is an active area of investigation.

SUMMARY

Anti-MDA5+ dermatomyositis has a wider spectrum of manifestations than previously thought. A high index of suspicion is needed not to miss atypical presentations. In the setting of acute interstitial lung involvement, once a confident diagnosis is made, an aggressive approach with early combined immunosuppression affords the best chances of survival.

Roles of biomarkers in anti-MDA5-positive dermatomyositis, associated interstitial lung disease, and rapidly progressive interstitial lung disease

BACKGROUND

Anti-melanoma differentiation-associated gene 5 (MDA5)-positive dermatomyositis (MDA5⁺ DM) is significantly associated with interstitial lung disease (ILD), especially rapidly progressive ILD (RPILD) due to poor prognosis, resulting in high mortality rates. However, the pathogenic mechanism of MDA5⁺ DM-RPILD is unclear. Although some MDA5⁺ DM patients have a chronic course of ILD, many do not develop RPILD. Therefore, the related biomarkers for the early diagnosis, disease activity monitoring, and prediction of the outcome of RPILD in MDA5⁺ DM patients should be identified. Blood-based biomarkers are minimally invasive and can be easily detected.

METHODS

Recent relative studies related to blood biomarkers in PubMed were reviewed.

RESULTS

An increasing number of studies have demonstrated that dysregulated expression of blood biomarkers related to ILD such as ferritin, Krebs von den Lungen-6 (KL-6), surfactant protein-D (SP-D), and cytokines, and some tumor markers in MDA5⁺ DM may provide information in disease presence, activity, treatment response, and prognosis. These studies have highlighted the great potentials of blood biomarker values for MDA5⁺ DM-ILD and MDA5⁺ DM-RPILD. This review provides an overview of recent studies related to blood biomarkers, besides highlighted protein biomarkers, including antibody (anti-MDA5 IgG subclasses and anti-Ro52 antibody), genetic (exosomal microRNAs and neutrophil extracellular traps related to cell-free DNA), and immune cellular biomarkers in MDA5⁺ DM, MDA5⁺ DM-ILD, and MDA5⁺ DM-RPILD patients, hopefully elucidating the pathogenesis of MDA5⁺ DM-ILD and providing information on the early diagnosis, disease activity monitoring, and prediction of the outcome of the ILD, especially RPILD.

CONCLUSIONS

Therefore, this review may provide insight to guide treatment decisions for MDA5⁺ DM-RPILD patients and improve outcomes.

Biomarkers of disease activity in dermatomyositis

PURPOSE OF REVIEW

This review provides updates regarding biomarker studies that address key clinical unmet needs, which relate to the evaluation of the disease activity in patients with dermatomyositis.

RECENT FINDINGS

Increasing evidence supports that the serum levels of dermatomyositis-specific antibodies (DM-MSAs), which include anti-Mi-2, anti-NXP2, anti-MDA5, anti-TNF1-γ, and anti-SAE, are correlated with the disease activity. Moreover, serial measurements of DM-MSA levels may help to predict the disease status. Beyond the MSA, macrophage activation-related biomarker-soluble CD163, CD206, neopterin, and galectin-3/9 are the most currently talked biomarkers for disease activity in dermatomyositis; new circulating T-cell subsets CD4+CXCR5+CCR7loPD-1hi and TIGIT+CD226+ CD4 T cells can potentially harbor biomarkers of disease activity in dermatomyositis. In addition, LDGs and NETs were also shown to be correlated with the disease activities of dermatomyositis.

SUMMARY

Promising candidate biomarkers are now available for evaluating disease activity in dermatomyositis. These biomarkers need external validation in other large cohort studies.