A 42 year old man presents with exertional dyspnea for 10 years, which rapidly progressed over the last 7 months to the point that it is now present even at rest. He also experienced a nonproductive cough and generalized weakness during the same time.

His medical history is unremarkable, he is not on any drugs, and he does not smoke. He worked as a stonecutter for a 10 year period, until 7 years ago.

His full blood count is normal, but the ESR is 45mm in the 1st hour.