A Case Report of McArdle Disease Diagnosed Following Statin-Induced Myositis

Cureus. 2023 Sep 5;15(9):e44701. doi: 10.7759/cureus.44701. eCollection 2023 Sep.

Abstract

McArdle disease is a rare condition, characterized by a deficiency of phosphorylase muscle isoform, an enzyme responsible for the breaking down of glycogen, necessary for obtaining energy. Patients typically present with exercise intolerance, myalgias, fatigue, cramps, muscle stiffness, and/or weakness induced by physical activity. The diagnosis is generally established late, with a median delay of about 29 years. We present the case of a female patient with a long history of myalgias, muscle weakness, and exercise intolerance, diagnosed with McArdle disease by the age of 74, after statin-induced myopathy. We aim to review the diagnosis and treatment of this disease, as a way to raise awareness among the medical community.

Keywords: exercise intolerance; mcardle disease; myalgias; myophosphorylase; statins.

Publication types

  • Case Reports