MRCP2-4749

A 50-year-old female has presented to your neurology clinic with complaints of difficulty lifting her arms during exercises at the gym for the past few months. She is visibly upset and tearful, mentioning that she has been using a lot of make-up to cover a new purple rash and swelling around her eyelids. She has no significant medical history or recent trauma and is generally healthy. She has had a dry cough for the past 6 months, which she attributes to her previous social smoking habit of up to 2 cigarettes every 2 weeks when going out with friends.

Upon examination, you note limited passive movement in both shoulders and hips due to tender deltoids and hip flexors. Power examination reveals 4-out-of-5 symmetrically in hip flexion and shoulder abduction. She has an elliptical erythematous rash around her eyes, and the skin around her fingers appears tough bilaterally. Auscultation of her chest reveals bibasal fine inspiratory crackles and normal heart sounds. Her observations show a low-grade temperature of 37.7 degrees. A chest radiograph shows bilateral fibrotic changes.

Her admission blood tests are as follows:

– Hb 121 g/l
– Platelets 590 * 109/l
– WBC 12.3 * 109/l
– ESR 20 mm/hr
– Creatine kinase 3000 u/l
– LDH 250 u/l

What is the most likely underlying diagnosis that unifies all of her symptoms?