A 45-year-old woman presents to the clinic with a three-month history of progressive difficulty performing daily activities such as rising from a chair, climbing stairs, and combing her hair. She also reports generalized fatigue and mild joint pain, which she initially attributed to overexertion. However, her symptoms have worsened over time, prompting her to seek medical attention. On physical examination, the physician notes bilateral proximal muscle weakness, particularly in the shoulder and hip girdles. The patient’s sensory examination is normal, with no deficits in touch, pain, or vibration. Notably, the physician observes a violaceous (purplish) rash on her eyelids, and scaly, erythematous patches over her knuckles. Laboratory testing reveals elevated creatine kinase (CK). Additionally, the patient tests positive for anti-histidyl tRNA synthetase (anti-Jo-1) antibodies. Which of the following is the most likely diagnosis?
