This is the hand from a 40 year old male smoker (40 pack years). He also notes the same findings in the other extremities. The patient is not diabetic and negative for ANA, RF, anticentromere antibody, Scl-70, antiphospholipid antibodies. Complement is normal and there are no genetic causes for clot-formation. Transthoracic echocardiography shows a normal heart.
Challenge: What's the diagnosis?
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