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What is If a patient with Raynaud's disease puts his hand in cold water, the hand appears: and explain in detail?
Raynaud's phenomenon is due to intense vasospasm of peripheral arteries that results in change in colour of ﬁngertips as a response to cold or emotion. It is seen in scleroderma and L.E.
One variant of systemic sclerosis is the CREST syndrome, an acronym of the five major findings: calcinosis cutis, Raynaud's phenomenon, oesophageal dysfunction, sclerodactyly, and telangiectasia. This form of the disease is sometimes not as severe as the usual systemic type. 
Raynaud syndrome. A vascular spasm in response to cooling, seen in the digits in connective tissue disorders.