Abstract We are presenting a case of Clinically Amyopathic Dermatomyositis (CADM) leading to a rapidly progressive ILD (Interstitial Lung Disease) that led to a severe ARDS (Adult Respiratory Distress Syndrome) A 67-year-old female with new-onset atrial fibrillation and hypertension was transferred for worsening hypoxemia and diffuse rashes with Gottron papules. On arrival, she was short of breath and hypoxic. A CT scan revealed ground-glass opacities indicative of NSIP. Following bronchoscopy and biopsy, her hypoxemia worsened, requiring intubation, which was complicated by difficulty leading to a pneumothorax and pneumomediastinum. Consultation with cardiothoracic surgery revealed a mild tear in the anterior bronchus. Due to her deteriorating P/F ratio, she underwent VV-ECMO cannulation and received minimal sedation. Testing showed MDA5 positivity and mildly + Fungitel, delaying pulse dose steroid and other potent immunosuppressant treatment. She was treated with glucocorticoids, but her condition did not improve significantly. After three days of pulse steroids and a first dose of rituximab, lung compliance showed mild improvement, but her atrial fibrillation became uncontrolled despite management with Dofetilide and beta-blockers. The family chose to withdraw life support, and the patient was pronounced dead shortly after transitioning to comfort care. Anti-MDA5 (anti-melanoma differentiation-associated gene 5) antibodies, linked to clinically amyopathic dermatomyositis (CADM), are primarily associated with rapidly progressive interstitial lung disease (RP-ILD), non-erosive arthritis, and vasculopathic lesions. In our patient, this antibody was tied to RP-ILD, pneumomediastinum and a new onset arrhythmia. Arrhythmia is a rare complication of CADM. It is classified under idiopathic inflammatory myopathy (IIM).Macrophages play a role in CADM, categorized as M1 (pro-inflammatory) and M2 (anti-inflammatory). M2 macrophages produce a soluble form of the mannose receptor (sCD206), which may influence immune responses. While the relationship between sCD206 and CADM is not fully understood, it has been noted to increase in RP-ILD cases associated with CADM.Our patient also experienced pneumomediastinum, which indicates poor prognosis and entails the requirement of immediate immunosuppression. The main treatments are glucocorticoids, calcineurin inhibitors, and cyclophosphamide, often used in combination or as triple therapy, which is escalated depending on the severity of the cases. In this case, rituximab was administered in. combination with pulse dose steroids. Rituximab is a monoclonal antibody that targets the CD20 receptors. It has shown a promising outcome in severe, refractory CADM-related RP-ILD. Prognosis for MDA5+ CADM-related RP-ILD is generally poor, but some reports suggest improved outcomes following bilateral lung transplant. This abstract is funded by: None
Rashmi et al. (Fri,) studied this question.