Raynaud's phenomenon is characterised by episodic attacks of digital vasospasm and ischaemia on exposure to cold, or less commonly, emotional stress. This results in a characteristic triphasic colour change in extremities (usually in fingers or toes)
- white - ischaemia; then
- blue - (deoxygenation) rewarming with a slow blood flow; then
- red - (reperfusion) normal colour returns; may be accompanied by throbbing pain and swelling due to reactive hyperaemia (1,2)
Ear and nose involvement can be seen as well in some patients (1). Attacks vary from minutes to hours. There may be associated hyperhidrosis.
The disease may occur as
- primary (idiopathic) Raynaud's phenomenon - which comprises the majority of cases (around 90%)
- secondary Raynaud's phenomenon - due to some underlying condition e.g.- systemic sclerosis (SSc), systemic lupus erythematosus (SLE), vasculitis, atherosclerosis and hypothyroidism (1,2).