Immune-mediated necrotizing myopathy due to statins exposure

Acta Myol. 2018 Dec 1;37(4):257-262. eCollection 2018 Dec.


Statin-induced necrotizing autoimmune myopathy (IMNM) is an autoimmune disorder induced by anti-3-hydroxy-3-methylglutaryl-coenzyme-A reductase (anti-HMGCR) antibodies. We performed a retrospective clinical, histological, and radiological evaluation of 5 patients with a 3-year therapeutic follow-up. All patients used statins and then experienced proximal weakness that persisted after drug cessation. Muscle biopsies revealed a primary necrotizing myopathy without inflammatory infiltrates. All patients required immunomodulant combination therapy to achieve clinical remission. Magnetic resonance imaging (MRI) showed the presence of edema in the medial gastrocnemius, posterior and central loggia of the thigh, posterior loggia of the arm, and the infraspinatus and subscapularis muscles, as well as extensive inflammation of the subcutaneous tissues and muscolaris fasciae. Serum analysis, muscle biopsy, and MRI are fundamental for IMNM diagnosis and follow-up. The growing use of statins in the general population raises the importance of acquaintance with this disease in clinical practice.

Keywords: HMGCR autoantibodies; muscular MRI; necrotizing myopathy.

MeSH terms

  • Autoantibodies / blood
  • Autoimmune Diseases* / chemically induced
  • Autoimmune Diseases* / diagnosis
  • Autoimmune Diseases* / immunology
  • Biopsy / methods
  • Correlation of Data
  • Female
  • Humans
  • Hydroxymethylglutaryl CoA Reductases / immunology*
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors* / administration & dosage
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors* / adverse effects
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors* / immunology
  • Magnetic Resonance Imaging / methods
  • Male
  • Middle Aged
  • Muscle, Skeletal / pathology*
  • Muscular Diseases* / chemically induced
  • Muscular Diseases* / diagnosis
  • Muscular Diseases* / immunology
  • Necrosis
  • Retrospective Studies


  • Autoantibodies
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors
  • HMGCR protein, human
  • Hydroxymethylglutaryl CoA Reductases