What's behind these calluses, pitted nails and swelling?
A 47-year-old woman presents with violaceous discolouration of the proximal nail folds on the fingers of both hands.
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Professor Dedee Murrell is head of the department of dermatology at St George Hospital and conjoint professor of dermatology at the UNSW, Sydney.
This article was co-authored by Clare Rogers, a medical student at the UNSW, Sydney.