In medicine, Raynaud's phenomenon is discoloration of the fingers or toes due to emotion or cold in a characteristic pattern in time: white, blue and red. more...
It is associated with a large number of diseases (mainly forms of vasculitis and hence belonging to rheumatology), but is idiopathic in most sufferers and is then called Raynaud's disease. Raynaud's phenomenon has also been observed in patients after receiving chemotherapy, particularly after regimens that included bleomycin.
The condition is painful and potentially dangerous for those who suffer from it. The primary cause of the pain and discoloration of the affected extremeties is vasospasm.
In pregnancy, this sign normally disappears due to increased surface blood flow.
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