title: Statin-associated polymyositis following omeprazole treatment.
abstract: Statins are an extensively used class of drugs, and myopathy is an uncommon, but well-described side effect of statin therapy. Inflammatory myopathies, including polymyositis, dermatomyositis, and necrotizing autoimmune myopathy, are even more rare, but debilitating, side effects of statin therapy that are characterized by the persistence of symptoms even after discontinuation of the drug. It is important to differentiate statin-associated inflammatory myopathies from other self-limited myopathies, as the disease often requires multiple immunosuppressive therapies. Drug interactions increase the risk of statin-associated toxic myopathy, but no risk factors for statin-associated inflammatory myopathies have been established. Here we describe the case of a man, age 59 years, who had been treated with a combination of atorvastatin and gemfibrozil for approximately 5 years and developed polymyositis after treatment with omeprazole for 7 months. Symptoms did not resolve after discontinuation of the atorvastatin, gemfibrozil, and omeprazole. The patient was treated with prednisone and methotrexate followed by intravenous immunoglobulin, which resulted in normalization of creatinine kinase levels and resolution of symptoms after 14 weeks. It is unclear if polymyositis was triggered by interaction of the statin with omeprazole and/or gemfibrozil, or if it developed secondary to long-term use of atorvastatin only.
authors.affiliation: Department of Internal Medicine, Marshfield Clinic, 1000 North Oak Avenue, Marshfield, WI 54449, USA. kanth.rajan@marshfieldclinic.org
authors.forename: Rajan
authors.initials: R
authors.lastname: Kanth
authors.forename: Milind S
authors.initials: MS
authors.lastname: Shah
authors.forename: Rafael Medina
authors.initials: RM
authors.lastname: Flores
mesh_terms: D000924:Anticholesteremic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D000069059:Atorvastatin; D004347:Drug Interactions; D004941:Esophagitis / Q000188:drug therapy; D015248:Gemfibrozil / Q000009:adverse effects* / Q000627:therapeutic use; D006538:Heptanoic Acids / Q000009:adverse effects* / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008727:Methotrexate / Q000627:therapeutic use; D008875:Middle Aged; D009203:Myocardial Infarction / Q000188:drug therapy; D009853:Omeprazole / Q000009:adverse effects* / Q000627:therapeutic use; D017285:Polymyositis / Q000139:chemically induced* / Q000175:diagnosis / Q000188:drug therapy; D011241:Prednisone / Q000627:therapeutic use; D054328:Proton Pump Inhibitors / Q000009:adverse effects* / Q000627:therapeutic use; D011758:Pyrroles / Q000009:adverse effects* / Q000627:therapeutic use; D016896:Treatment Outcome; D028761:Withholding Treatment
chemical_list: D000924:Anticholesteremic Agents; D006538:Heptanoic Acids; D054328:Proton Pump Inhibitors; D011758:Pyrroles; D000069059:Atorvastatin; D009853:Omeprazole; D015248:Gemfibrozil; D011241:Prednisone; D008727:Methotrexate
keywords: Autoimmune; Myopathy; Statins