Raynaud Phenomenon: Diagnosis and Management

Introduction

Raynaud phenomenon is an exaggerated vasospastic response of the digital arteries to cold or emotional stress, producing episodic colour change and discomfort in the fingers (and sometimes toes, ears and nose). It affects a substantial minority of the population, most of whom have a benign, primary form with no underlying disease.¹

The essential clinical task - and the reason this is examined so consistently - is distinguishing primary Raynaud disease, which needs reassurance and simple measures, from secondary Raynaud phenomenon, which can be the earliest sign of a serious underlying connective tissue disease, sometimes appearing years before any other feature.

Pathophysiology

Cold exposure normally causes mild digital vasoconstriction to conserve core heat. In Raynaud phenomenon, this response is exaggerated - digital arteries and arterioles constrict excessively, transiently occluding blood flow to the fingers. As flow returns, characteristic colour changes follow the sequence of ischaemia, deoxygenation and reperfusion.

1. White - vasospasm cuts off arterial flow, causing pallor and often numbness
2. Blue - stagnant deoxygenated blood in the digits produces cyanosis
3. Red - as vasospasm resolves, reactive hyperaemia causes redness, throbbing and pain

Not every patient experiences the full triphasic sequence - white-only or white-then-blue presentations are common, and the classic three-colour description is a helpful pattern to recognise rather than a strict diagnostic requirement.

Clinical features

• Episodic attacks triggered by cold exposure, handling cold objects, or emotional stress, typically lasting minutes to a couple of hours
• Digits most often affected, though the toes, ears, nose and nipples can also be involved
• Numbness or tingling during the white phase, and throbbing pain as blood flow returns in the red phase
• Symptom severity scored by frequency and duration of attacks, and by whether pain or ulceration accompanies them - useful for tracking response to treatment over time
• A careful history of onset age, symmetry, and associated symptoms (skin tightening, joint pain, dry eyes/mouth, dysphagia, breathlessness, photosensitive rash) does most of the diagnostic work at first presentation

Examination

• Inspect the digits between attacks for pitting scars, ulceration, or fixed colour change suggesting chronic ischaemic damage
• Palpate peripheral pulses - normal in Raynaud phenomenon; reduced or absent pulses point toward a large-vessel or embolic cause instead
• Look for skin changes of an underlying connective tissue disease - sclerodactyly, telangiectasia, calcinosis - which may be subtle early on
• Examine the hands for synovitis or joint swelling, and screen more broadly for signs discussed in the individual connective tissue disease articles

Differential diagnosis

• Acrocyanosis - persistent, painless blue discolouration of the hands, without the episodic pattern or pallor phase of Raynaud phenomenon
• Chilblains (perniosis) - localised, itchy, inflamed lesions after cold exposure, rather than transient digital colour change
• Peripheral arterial disease / embolism - a single persistently cold, painful, pulseless digit rather than an episodic bilateral pattern
• Carpal tunnel syndrome - numbness and tingling, but in a median nerve distribution and without colour change
• Erythromelalgia - the near-opposite presentation, with episodic red, hot, burning extremities rather than pallor and cyanosis

Primary versus secondary Raynaud phenomenon

Causes of secondary Raynaud phenomenon

• Connective tissue disease - systemic sclerosis has by far the strongest association (Raynaud phenomenon occurs in almost all patients, often years before other features), also mixed connective tissue disease, SLE, Sjogren syndrome and dermatomyositis
• Occupational - hand-arm vibration syndrome (vibration white finger) from prolonged use of vibrating tools
• Drugs - beta-blockers, ergotamine, some chemotherapy agents (bleomycin, cisplatin), cocaine and amphetamines
• Haematological - cryoglobulinaemia, polycythaemia, and other hyperviscosity states
• Thoracic outlet syndrome and other causes of vascular compression
• Smoking - a recognised aggravating factor in both primary and secondary disease

Investigations

• Nailfold capillaroscopy - examines the capillaries at the nail bed under magnification; normal in primary disease, showing dilated, distorted or dropped-out capillaries in secondary disease, particularly systemic sclerosis
• ANA and extended autoantibody panel (anti-centromere, anti-Scl-70, anti-U1-RNP, anti-dsDNA) - if secondary disease is suspected clinically
• FBC - polycythaemia or evidence of a haematological cause
• ESR/CRP - raised in an underlying inflammatory connective tissue disease
• Cryoglobulins - if the history suggests a hyperviscosity syndrome

Management

General measures (all patients)

• Keep the whole body, not just the hands, warm - gloves, hand and foot warmers, layered clothing
• Avoid abrupt cold exposure and minimise handling of cold objects (frozen food, cold water)
• Smoking cessation
• Review and, where possible, stop precipitating drugs - particularly beta-blockers
• Avoid excess caffeine, which can worsen vasospasm

Pharmacological treatment

Nifedipine (a dihydropyridine calcium channel blocker) is first-line for patients whose symptoms are not adequately controlled by general measures alone.

• Second-line options - losartan, fluoxetine, or topical glyceryl trinitrate, used where calcium channel blockers are ineffective or not tolerated
• IV prostacyclin analogues (epoprostenol, iloprost) - for severe secondary disease with critical digital ischaemia, given as intermittent infusions
• Endothelin receptor antagonists (bosentan) - reduce the occurrence of new digital ulcers in systemic sclerosis-associated Raynaud phenomenon
• PDE5 inhibitors (sildenafil) - an option for refractory digital ischaemia
• Digital sympathectomy - a surgical option reserved for severe, refractory cases with critical ischaemia threatening tissue loss

Where secondary Raynaud phenomenon is identified, management of the underlying connective tissue disease runs alongside symptomatic treatment of the vasospasm itself.

Complications

Primary Raynaud disease causes discomfort but no lasting tissue damage. Secondary Raynaud phenomenon, particularly in systemic sclerosis, can progress to digital ulceration, chronic pain, and in severe cases critical digital ischaemia and gangrene, occasionally requiring digit amputation. Recurrent digital ulcers are also a source of pain, infection risk and significant impact on hand function and quality of life.

Red flags

Prognosis

Primary Raynaud disease is benign and often improves with simple measures, though it can persist lifelong without causing harm. Secondary Raynaud phenomenon carries the prognosis of its underlying cause - it is a marker of disease rather than a disease in itself, and its severity often, though not always, tracks the severity of the associated connective tissue disease, particularly systemic sclerosis.