26th February 2025

A 35-year-old female is reviewed in rheumatology clinic.

A 35-year-old female is reviewed in rheumatology clinic. She has noted increasing shortness of breath recently on exertion. She has also noticed increasing erythematous lesions on her face and hands over the last few months. She has a painful lesion on her thumb with white chalky lumps underneath.

She has a past medical history of limited cutaneous systemic sclerosis.

On chest auscultation, the lungs are clear. You can hear a prominent second heart sound.

Chest X-ray: the lung fields are clear. Heart size is normal.

Serial lung function tests are demonstrated below:

 What is the most likely diagnosis?

Select the SINGLE most appropriate option from the list below. Select ONE option only.