10th March 2024

Raynaud’s Phenomenon

Raynaud’s phenomenon (RP) is defined as a vascular response to cold temperature or emotional stress that is above the normal physiological response. The pathogenesis of RP is a complex interplay of different factors, including genetic, neural, vascular and intravascular factors. This vasospastic condition affects around 5% of the population, is more common in women and can be classified as primary or secondary. Primary RP is more common before the age of 30 in contrast to secondary RP, which usually presents after the age of 40. Secondary causes include:

• Vascular
• Occupational
• Autoimmune
• Drug/chemical-related
• Conditions associated with increased plasma viscosity and reduced digital perfusion
• Other causes, e.g., carpal tunnel syndrome, frostbite, and hypothyroidism

Clinical presentation

RP presents as a characteristic colour change in hands and sometimes feet associated with cold temperatures or emotional stress. Most patients will not present to a healthcare provider during the episodes due to the regular short durations but will capture the episodes on their mobile phone or describe the typical clinical picture. The classical triad of colour change will traverse from white (pallor) to blue (cyanosis) to red before turning back to the patient’s regular skin colour. 

Diagnosis

RP is considered a symptom, not a diagnosis; however, the cause should be investigated to identify whether this is primary or secondary. The burden of digital complications should be considered to aid the decision on whether drug or surgical intervention is needed. In primary RP nailfold capillaroscopy, FBC, ANA and ESR should be normal. In secondary RP or systemic sclerosis, these will be abnormal. Once the cause is established, the management will be tailored to the underlying cause and consideration for symptom control with drugs or surgical treatment. 

Management

Initial management of primary RP involves conservative measures such as patient education to avoid the cold, hand-warming gloves and smoking cessation. After this, first-line medications such as calcium channel blockers, phosphodiesterase inhibitors, ARBs, SSRIs, alpha-blockers, ACE-I and topical nitrates can be used. In refractory RP or where there is digital ulceration, intravenous prostanoid can be used. When all medical treatments fail to control RP and ulceration and critical ischemia begins to occur, a digital sympathectomy should be considered.