Rapid Clinical Improvement of Anti-HMGCR Immune-mediated Necrotizing Myopathy (IMNM) Treated with Efgartigimod

Severe Necrotizing Myositis in a Patient with Anti-3-Hydroxy-3-Methylglutaryl-Coenzyme A Reductase (HMGCR), Melanoma Differentiation-Associated Gene 5 (MDA-5), Clinically Amyopathic Dermatomyositis 140 (CADM-140), Nuclear Matrix Protein 2 (NXP-2), and Rib