Raynaud’s syndrome refers to paroxysmal spasms of small arteries, which lead to a sequence of typical symptoms in affected areas, including pallor and coldness, cyanosis and pain, followed by redness and recovery. It most often occurs in response to cold stimuli or emotional fluctuations.
Etiology and Pathology
Raynaud's disease typically refers to cases solely caused by vascular spasms without underlying conditions, with the disease course being relatively stable. In contrast, Raynaud's phenomenon involves vascular spasms accompanied by other systemic diseases, presenting a more severe course and potentially leading to necrosis of the fingertips or toes. Collectively, both conditions are grouped under the term Raynaud's syndrome. Although the exact cause of Raynaud’s syndrome remains unclear, several factors are considered relevant, including cold exposure, emotional stress, infections, gonadal function, sympathetic nervous system dysfunction, immune abnormalities, and genetic predisposition.
Pathological changes depend on the stage of the disease. In the early stage, vascular spasms result in temporary ischemia of distal tissues. In later stages, thickening of arterial intima, rupture of elastic fibers, narrowing of the vascular lumen, and reduced blood flow may occur. In cases with secondary thrombus formation leading to vascular occlusion, trophic changes, fingertip (or toe-tip) ulcers, or necrosis may develop.
Clinical Manifestations
Raynaud’s syndrome is more common among young women, frequently affecting the fingers and often involving both hands symmetrically. Occasionally, it may involve the toes, cheeks, or outer ears. The characteristic symptoms occur in sequence: pallor, cyanosis, and redness. During the early stages, episodes frequently happen during the cold seasons, with each flare lasting from several minutes to tens of minutes. As the condition progresses, the frequency of attacks increases, and episodes last longer, with occurrences even during warmer seasons when exposed to cold stimuli.
During attacks, patients often experience uncomfortable numbness, though severe pain is rare. Between episodes, symptoms are typically absent except for slightly lower skin temperature in the fingers. Ulceration of the fingertips (or toes) is rare, and radial artery (or dorsalis pedis artery) pulsations remain normal.
Examination and Diagnosis
The diagnosis can be made based on the characteristic symptoms during episodes. If needed, a cold stimulation test may be performed, wherein the hand is immersed in ice water for 20 seconds, followed by measurement of finger skin temperature. Prolonged rewarming time (normally around 15 minutes) may indicate Raynaud’s syndrome.
Treatment
Maintaining warmth helps prevent or reduce the frequency of episodes. Smoking cessation is beneficial for individuals who smoke. Medication therapy primarily involves drugs that inhibit the transmission of sympathetic neuromuscular signals. Prostaglandin E1 may also be utilized for its vasodilatory and anti-platelet aggregation effects. In cases linked to autoimmune or other systemic diseases, treatment of the underlying condition should be undertaken. Most patients experience symptom relief or cessation of disease progression following medical treatment.