raynaud’s disease

Raynaud’s phenomenon is a condition that causes reduced blood supply to the fingers and toes in response to certain conditions such as, coldness, and cases of emotional stress. It causes pain, numbness and tingling in the areas affected and can be reversed through lifestyle and medical treatment.

Epidemiology

In most populations, Raynaud’s phenomenon is found to affect 3-5% of the general population
A 7-year study found that in white patients within the US, prevalence rates were 11% in women and 8% in men [1]
The prevalence ranges from 2-20% of women and 1-12% in men depending on factors such as geographic location and population studied [2]
In most cases, Raynaud’s phenomenon is in its primary stage (80-90%)
More common in women than men
Typically develops at a younger age (between the 20-30th years of life) [3]

Raynaud’s phenomenon

Blue/white colour change of the extremities (toes) due to the constriction of blood vessels

Pathophysiology [4]

Medical students
- Three mechanisms of Raynaud phenomenon:
  - Decreased blood flow
  - Blood vessel constriction
  - Neurogenic and inflammatory immune responses
- Somatosensory system involved in temperature perception:
  - A-delta and unmyelinated C-fibers (nerve fibres related to pain) activated by cold temperatures
  - This triggers the activation of cold receptor TRPM8 for monitoring cold variations
  - TRPM8 activation leads to vasoconstriction, thermogenesis, and cold avoidance
- Sympathetic nervous system response to cold temperatures:
  - Release of vasoconstricting neuropeptides and norepinephrine
  - Vasoconstriction of arteriole smooth muscle and reduced blood flow to the skin
  - Endothelin-1 release in secondary Raynaud phenomenon causing vasoconstriction
- Primary Raynaud phenomenon:
  - Increase in alpha-2 adrenergic sensitivity in digital and cutaneous vessels
  - Vasoconstrictive response to cold temperatures and emotional stress
  - Alpha-2 adrenergic receptor inhibitors reduce severity of cold-induced attacks
- Secondary Raynaud phenomenon:
  - Underlying disease disrupts vessel reactivity to cold temperatures
  - Endothelial function compromised leading to vasoconstriction and tissue ischemia

Patients
- Three mechanisms of Raynaud phenomenon:
  - Decreased blood flow
  - Blood vessel narrowing
  - Neurogenic (involving nerves in the body) and inflammatory immune responses
- Somatosensory (related to the body and senses) system involved in temperature perception:
  - Nerves responsible for the perception of pain are activated by cold temperatures
  - This causes the activation of cold receptors for monitoring cold variations
  - This leads to blood vessel narrowing, heat production which is lost to the surroundings, and cold avoidance
- Sympathetic nervous system (this triggers your fight or flight) response to cold temperatures:
  - Release of hormones (chemicals in the body) which trigger blood vessel narrowing
  - Narrowing of the muscle layers of the artery and reduced blood flow to the skin
  - The protein, Endothelin-1, is released in secondary Raynaud syndrome (developed from a primary condition) causing blood vessel narrowing
- Primary Raynaud phenomenon:
  - Increase in a nerve receptor sensitivity ( increased response to conditions in the body) found in the finger and skin blood vessels
  - Blood vessel narrowing is triggered in response to cold temperatures and emotional stress
  - Substances that stop the activation of certain nerve receptors leads to a reduction in the severity of cold-induced attacks
- Secondary Raynaud phenomenon:
  - Underlying disease disrupts the body’s reaction to vessels in cold temperatures
  - Damage to the Endothelial function leads to blood vessel narrowing and reduction to oxygen supply to the tissue

Source: NHS

Raynaud’s phenomenon
Fingernails appear paler if you have darker skin

Source: NHS

Raynaud’s phenomenon
Blue discolouration of the fingers

Causes [5]
- Primary- without being associated with another condition
  - Some evidence of inheritance (run in families)
- Secondary- association with another condition
  - Autoimmune conditions (eg. rheumatoid arthritis, lupus) 1 in 10 patients are found to develop an autoimmune condition after being diagnosed with primary Raynaud’s syndrome
  - Infections such as Hepatitis B and C as well as blood born viral infections
  - Cancer (eg. ALL, myeloma)- can cause secondary Raynaud’s
  - Medicines including;
  - Anti-migraine medications
  - Beta-blockers
  - Chemotherapy
  - Contraceptive pills
  - And other drugs used to treat high blood pressure, hormone replacement, decongestants and illegal drugs like cocaine.
Injury and overuse
History of frostbite damaging skin and tissues
Vibration white finger (caused by vibrations from certain tools eg. hammer drills and chainsaws)

Risk factors [6]
- Autoimmune diseases (eg. diabetes, arthritis, MS)
- Chemical exposure
- Smoking
- Injury/ trauma to the skin
- Overuse of actions such as using vibrating tools or typing
- Certain medications (see above)

Presentation [7]
- Coldness
- Burning pain
- Tingling (paraesthesia)
- Discolouration of the fingers
- Cyanosis (blueness)
- Pallor (paleness)
- Ulcer formation and tissue damage in sever cases of Raynaud’s syndrome

Investigations [5]
- Clinical examination where hands are placed in cold water/air to check for the presentation of Raynaud’s syndrome in the clinic
- Blood tests including;
  - A full blood count to check for infection
  - Antinuclear antibodies test (presence of proteins that protect your immune system) to check for an abnormally reactive immune system
  - Erythrocyte sedimentation rate (tests how quickly red blood cells can settle to the bottom of a test tube) to check for an immune system disorder (overreaction of the immune system)

Differential diagnosis [3]
- Chilblains
- Acrocyanosis- blueness triggered by the cold
- Erythromelalgia- redness of the hands/feet
- Obstructive vessel conditions (eg. embolism)
- Livedo reticularis- blue discolouration of the skin and mottled skin (marked spots with patches of colour)
- Peripheral (hands/feet) nerve injury
- Shoulder-hand syndrome- causes continuous pain in the hands/feet associated with vessel reflex changes

Management [7]
- Medical students
  - Lifestyle changes:
    - Avoidance of cold and smoking cessation
    - Use of relaxation techniques (e.g., biofeedback) or counselling if stress is a trigger
  - Medications:
    - Vasodilating calcium channel blockers (e.g., nifedipine, amlodipine, felodipine, isradipine)
    - Treatment of Secondary Raynaud Syndrome:
      - Focus on treating the underlying disorder
      - Similar medications to Primary Raynaud Syndrome:
        Calcium channel blockers (e.g., nifedipine, amlodipine, felodipine, isradipine)
      - Additional treatments for ischemic ulcers may include antibiotics, analgesics, and surgical debridement
      - Low-dose aspirin may prevent thrombosis but could worsen vasospasm
- Patients
  - Lifestyle changes:
    - Avoidance of cold and smoking cessation
    - Use of relaxation techniques (e.g., biofeedback) or counselling if stress is a trigger
  - Medications:
    - Vasodilating (blood vessel widening) drugs called calcium channel blockers (blocks the calcium intake to the heart) (e.g., nifedipine, amlodipine, felodipine, isradipine)
    - Treatment of Secondary Raynaud Syndrome:
      - Focus on treating the underlying disorder
      - Similar medications to Primary Raynaud Syndrome:
        Calcium channel blockers (e.g., nifedipine, amlodipine, felodipine, isradipine)
      - Additional treatments for ischemic ulcers (sores caused by a lack of oxygen supply) may include antibiotics, analgesics, and surgical debridement (treating a wound in the skin)
      - Low-dose aspirin may prevent thrombosis (blood clot formation) but could worsen vasospasm (narrowing of the arteries caused by the constant narrowing movement of the arteries)

Source: NHS

Raynaud’s phenomenon
Skin may turn white/lighter on the fingertips

Source: NI Direct Government Services

Raynaud’s phenomenon
Paleness on the fingertips on darker skin

Complications [6]
- Sore areas of the fingers may progress into tissue damage and death (gangrene)
Myths [8]
- Raynaud’s is a rare disease
- It only affects fingers and toes
- Raynaud’s phenomenon is caused by poor circulation
- The only treatment is to stay warm
- Symptoms only include red, white and blue discolouration

Questions to ask your doctor
- How can I avoid the reoccurrence of symptoms?
- How is it diagnosed?
- Is it a hereditary condition?
- Will Raynaud’s get worse over time?