Increased dosage of cyclosporine induces myopathy with increased seru creatine kinase in an elderly patient on chronic statin therapy

Abstract

What is known and objective: The concomitant administration of atorvastatin and cyclosporine has been shown to increase the serum concentration of 3-hydroxy-3-methylglutaryl coenzyme A, which may be associated with the elevation of creatine kinase and an increased risk of myopathy. Our objective is to report on a case of statin-induced myopathy associated with concomitant use of cyclosporine and other contributing factors.

Case summary: An 88-year-old Chinese male patient with comorbidities received polypharmacy treatment, including atorvastatin and cyclosporine. After the dosage of cyclosporine was increased to 300 mg every day for 8 months, the patient developed body pain and leg weakness, with a serum creatine kinase increase and evidence on magnetic resonance imaging of muscle oedema.

What is new and conclusion: Cyclosporine is a moderate inhibitor of the cytochrome P450 CYP3A4 isoenzyme, which is known to increase the serum level of atorvastatin. We hypothesized that the pharmacological and pharmacokinetic properties of atorvastatin-induced myopathy are the result of its interaction with high dosage of cyclosporine.

Keywords: creatine kinase; cyclosporine; drug-drug interactions; myopathy; statin.