SHM Converge Scientific Abstract ePoster Gallery-A Serious Side Effect of Statins: Autoimmune Necrotizing Myopathy

Pdf Summary

This case describes an 82-year-old African American woman with type 2 diabetes, chronic kidney disease, prior stroke with residual weakness, and hyperlipidemia treated with atorvastatin who presented with worsening generalized weakness and new left leg pain. Because of her prior neurologic deficits, her symptoms were initially thought to represent deconditioning. However, examination showed diffuse weakness, and labs revealed markedly elevated creatine kinase (CK 3795 U/L), elevated aldolase, and mildly increased inflammatory markers. Atorvastatin was stopped.<br /><br />Electromyography suggested an irritative myopathy with myotonia. A muscle biopsy was obtained, and she was started on high-dose prednisone, after which her clinical status improved and CK levels declined. Myositis-specific antibodies were negative, but anti-HMGCR antibody was strongly positive. Biopsy showed active and chronic necrotizing myopathy, confirming statin-associated immune-mediated necrotizing myopathy (IMNM).<br /><br />She was discharged on high-dose prednisone with a slow taper through rheumatology follow-up. Two months later, she was readmitted for persistent weakness and treated with prednisone, IVIG, and methotrexate, though improvement remained limited.<br /><br />The discussion emphasizes that IMNM is a rare but serious complication of statin therapy. Unlike self-limited statin myotoxicity, symptoms do not resolve after statin discontinuation. Typical features include progressive proximal muscle weakness, elevated CK, and positive anti-HMGCR antibodies, often in older patients with risk factors such as diabetes and CKD. Diagnosis relies on recognizing persistent weakness after statin exposure and confirming with antibody testing and muscle biopsy. Treatment requires statin cessation plus aggressive immunosuppression, often with corticosteroids and steroid-sparing agents such as methotrexate or IVIG. The authors stress maintaining a high index of suspicion to avoid misattributing weakness to deconditioning and delaying treatment.

Asset Subtitle

Komal Khoja

Meta Tag

Author List Komal Khoja, Luke J. Rasmussen, Pinky Jha, Thomas A. Kotsonis, Yasir Abdelgadir

Category Clinical Vignettes

Concept Statin-induced necrotizing autoimmune myopathy

Concept Proximal Weakness

Concept Anti-HMGCR Antibody

Concept Creatine Kinase

Concept Statin discontinuation

Distinguished Non-Finalist

Presenter Organization Medical College of Wisconsin

Presenting Author Komal Khoja

Track Adult

Keywords

statin-associated immune-mediated necrotizing myopathy

IMNM

anti-HMGCR antibody

atorvastatin

creatine kinase elevation

proximal muscle weakness

muscle biopsy

prednisone

IVIG

methotrexate

Statin-induced necrotizing autoimmune myopathy

Proximal Weakness

Anti-HMGCR Antibody

Creatine Kinase

Statin discontinuation