Anti-SAE autoantibody in dermatomyositis: original comparative study and review of the literature.

OBJECTIVE: Among specific autoantibodies in DM, the anti-small ubiquitin-like modifier activating enzyme (SAE) antibody is rare. We aim to describe the clinical characteristics, cancer prevalence, and muscle pathology of anti-SAE-positive DM. METHODS: Patients with a diagnosis of DM and sera positive for the anti-SAE antibody were recruited from 19 centres in this retrospective observational study. The available muscular biopsies were reviewed. We conducted a comparison with anti-SAE-negative DM and a review of the literature. RESULTS: Of the patients in the study (n = 49), 84% were women. Skin involvement was typical in 96% of patients, with 10% having calcinosis, 18% ulceration and 12% necrosis; 35% presented with a widespread skin rash. Muscular disease affected 84% of patients, with mild weakness [Medical Research Council (MRC) scale 4 (3, 5)], although 39% of patients had dysphagia. Muscular biopsies showed typical DM lesions. Interstitial lung disease was found in 21% of patients, mainly with organizing pneumonia pattern, and 26% of patients showed dyspnoea. Cancer-associated myositis was diagnosed in 16% of patients and was responsible for the majority of deaths, its prevalence being five times that of the general population. IVIG therapy was administered to 51% of the patients during the course of the disease. Comparison with anti-SAE-negative DM (n = 85) showed less and milder muscle weakness (P = 0.02 and P = 0.006, respectively), lower creatinine kinase levels (P < 0.0001) and less dyspnoea (P = 0.003). CONCLUSION: Anti-SAE positive DM is a rare subgroup associated with typical skin features but a potentially diffuse rash, a mild myopathy. Interstitial lung disease defines an organizing pneumonia pattern. Cancer associated DM prevalence is five times that of the general population. TRIAL REGISTRATION: ClinicalTrials.gov, http://clinicaltrials.gov, NCT04637672.

Cardiac involvement in adult-onset Still's disease: Manifestations, treatments and outcomes in a retrospective study of 28 patients.

OBJECTIVE: Adult-onset Still's disease (AOSD) is a rare inflammatory disease that may be life-threatening if complicated by cardiac problems. We performed a retrospective multicenter study to describe the manifestations, treatments and outcomes of cardiac involvement in AOSD. METHODS: We reviewed the medical databases of eight centers. All AOSD patients identified as fulfilling Yamagushi's or Fautrel's criteria were included in the study. Cardiac involvement, clinical manifestations, laboratory features, the course of the disease and treatments were evaluated. RESULTS: We included 96 AOSD patients in this study: 28 (29%) had documented cardiac involvement (AOSD + C group) and 68 (71%) had no cardiac involvement (control group). Cardiac complications were observed at diagnosis in 89% of cases. It were pericarditis (n = 17), tamponade (n = 5), myocarditis (n = 5) and non-infectious endocarditis (n = 1). Levels of leukocytes, neutrophils and C-reactive protein were significantly higher (p = 0.02, p = 0.02 and p = 0.002, respectively in the AOSD + C group than in the control group. Admission to intensive care, and the use of biotherapy were more frequent during follow-up in the AOSD + C group than the control group (p = 0.0001 and p = 0.03 respectively). Cardiac involvement was associated with refractory form in multivariate analyzed (p = 0.01). Corticosteroids were effective with or without methotrexate in 71% of patients but not in severe involvement as myocarditis or tamponade. CONCLUSION: Cardiac complications are frequent, inaugural, can be life-threatening and predictive of a refractory course in patients with AOSD. Systematic cardiac screening should be proposed at diagnosis and biotherapy early use should be considered especially in myocarditis.

Outcome of anti-PL12 positive patients with antisynthetase syndrome.

OBJECTIVES: The aim of the present study was to assess the outcome in anti-PL12 patients with antisynthetase syndrome (ASS). METHODS: The medical records of anti-PL12 (n=5) patients with ASS were retrospectively analyzed without prior selection. To exclude false-positive patients, we included patients who were successively tested positive for anti-PL12 antibody at least twice by immunodot and/or Western blot. RESULTS: Anti-PL12 patients experienced: myositis (n=2), Raynaud's phenomenon (n=2), mechanic's hands (n=1), joint impairment (n=4), digestive involvement (n=2), and interstitial lung disease (ILD) (n=4). The two patients with myositis exhibited deterioration of muscle manifestations despite therapy. As regards outcome of ILD, patients developed resolution (n=1), stabilization (n=1) or deterioration (n=2) of pulmonary status. One patient died of pyogenic pneumonia. CONCLUSION: Our series underscores that the presence of anti-PL12 antibody is associated with a particular phenotype of ASS characterized by: (1) less frequent although severe/steroid refractory myositis; (2) less common mechanic's hands and calcinosis cutis; (3) both frequent and severe ILD. Taken together, our findings suggest that PM/DM patients should routinely undergo the search for anti-PL12 antibody as this autoantibody appears to impact patients' prognosis. Furthermore, ILD patients with anti-PL12 antibody should routinely undergo clinical screening for underlying ASS.