Statin-induced Myonecrosis—A Rare Adverse Effect of a Common Drug: A Case Report

Background: Clinically significant statin-induced myonecrosis is a rare clinical disorder that affects the skeletal muscles of patients taking statin medication. Its clinical presentation ranges from mild muscle pain to muscle weakness associated with significant elevation (>10×) of serum creatinine kinase (CK). Early screening, identification, and treatment of statin-induced myopathy are vital as it may lead to drug discontinuation and poor medication adherence. Case Report: We report a 40-year-old male diabetic patient who visited our neurology referral clinic with a two-week history of muscle pain associated with proximal extremities’ weakness, which later progressed to involve the distal extremity muscles of his upper and lower limbs. A week before his presentation to our hospital, he became wheelchair-bound. Six months before his admission, he was started on a daily dose of 40 mg oral simvastatin for prevention, given his cardiovascular risk factors. No history of fever, headaches, abnormal body movement; no personal or family history of similar illness; no history of trauma, alcohol use, smoking, or use of herbal medication was elicited. His CK levels were elevated 19 times, and electromyography examination showed a myopathic pattern in proximal muscles. Following the discontinuation of simvastatin, the patient’s muscle weakness significantly improved. In addition, his serum CK levels also lowered significantly on his follow-up evaluation. Conclusion: This case describes a diabetic patient with statin-induced myonecrosis, managed conservatively through statin withdrawal. It also highlights the benign prognosis in younger patients, showing that the condition generally has a favorable outcome with timely diagnosis and management.