Shane is a 42-year-old carpenter who presents with a painful black, left middle fingertip, present for two months.

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<p>Shane is a 42-year-old carpenter who presents with a painful black, left middle fingertip, present for two months.</p><p>Shane is accustomed to traumatic subungual haematomas in his line of work, but this episode has been odd, in that there was no clear precipitating injury, and before the fingertip went black it had been tender, numb and red for about a month.</p><p>No other digits are affected, though he describes new onset of Raynaud’s phenomenon the previous winter.</p><p>Shane is otherwise well with no past or family history of note. He is a smoker with a 20-pack-year history.</p><p>On examination, vital signs are unremarkable. Brachial pulses are normal but left radial and ulnar pulses are reduced.</p><p>Skin and joint examination is otherwise unremarkable. Blood tests reveal normal EUC, LFT, FBC, coagulation profile, autoimmune screen and inflammatory markers.</p>

Dr Kate Kelso is a GP and medical editor at Australian Doctor.