What is vibratory angioedema?
Vibratory angioedema is sometimes mistaken for vibratory urticaria. Vibratory urticaria is another form of chronic inducible urticaria, where vibration leads to wealing rather than angioedema.
Who gets vibratory angioedema?
Vibratory angioedema is one of the rarest forms of chronic inducible urticaria. There are few cases reported, and its prevalence is unknown.
Both genetic and acquired variants of vibratory angioedema have been reported. The hereditary type has been observed to have an autosomal dominant pattern of inheritance.
What causes vibratory angioedema?
The pathophysiology of vibratory angioedema is not fully understood. Symptoms are presumed to be triggered by histamine release from the activation and degranulation of mast cells stimulated by vibration.
Familial cases have been associated with a mutation in the ADGRE2 gene, resulting in mast cell sensitisation to vibration-induced degranulation.
A number of associated triggers have been documented, including:
- Power-tools, such as drills, jack-hammers, and metal grinders
- Lawn mowing
- Horseback riding
- Towelling or massaging
- Playing musical instruments, such as saxophone and trumpet
Anaphylaxis has also been documented in response to full-body vibratory massage.
What are the clinical features of vibratory angioedema?
- The most commonly implicated areas are those with the highest exposure to a stimulus, typically the hands.
- The intensity and duration of the vibration stimulus are usually proportional to the severity of the symptoms.
- Vibratory angioedema is distinct from other forms of chronic inducible urticaria that cause wealing.
- Skin contact with a vibration stimulus results in symptoms within 10 minutes.
- The peak in severity is at 4–6 hours, with complete resolution of vibratory angioedema within 24 hours.
In rare instances, a patient may also experience systemic symptoms following prolonged or extensive exposure to vibration, including:
- Generalised erythema
What are the complications of vibratory angioedema?
Many patients with vibratory angioedema have difficulty avoiding the stimuli, particularly relating to their occupation, impacting their lifestyle and ability to socialise.
How is vibratory angioedema diagnosed?
The history of angioedema or erythema after exposure to vibratory stimuli is suspicious of vibratory angioedema. A vibration provocation test is recommended to confirm the diagnosis.
Vibration provocation test
A vibratory provocation test is conducted as follows:
- Apply a vortex or mixer on a level plane with the forearm skin
- Induce the vibration stimulus for 5 minutes
- Assess the skin for angioedema
- Monitor the site for 4-6 hours as a delayed response occurs in some patients.
Patients should avoid antihistamines for several days prior to testing.
Other provocation tests should be conducted to exclude other forms of chronic inducible urticaria if the results are equivocal.
What is the differential diagnosis for vibratory angioedema?
Other causes of inducible angioedema and urticaria include the following.
- Vibratory urticaria — vibration provokes weals. The resulting reaction should be closely examined to detect angioedema.
- Delayed pressure urticaria
- Symptomatic dermographism — scratching, rubbing, or stroking the skin results in the rapid onset of pruritic wealing.
- Aquagenic urticaria — contact with water produces urticaria.
- Cold urticaria — cold contact results in pruritic weals.
- Solar urticaria — ultraviolet radiation results in erythema or wealing within minutes of exposure.
- Heat urticaria — heat contact results in wealing.
- Cholinergic urticaria — increase in body temperature is associated with small weals.
- Contact urticaria — direct contact with a specific substance results in a localised urticarial reaction.
Classification of inducible urticaria is according to the stimulus or stimuli that provoke the urticaria confirmed with an appropriate provocation test.
What is the treatment for vibratory angioedema?
The mainstay of treatment is to avoid vibratory stimuli where possible. Patients should be reminded of the risk of prolonged or intense exposure to vibration leading to more significant systemic involvement.
Symptomatic management focuses on the use of second-generation non-sedating H1 antihistamines, such as loratadine and cetirizine.
What is the outcome for vibratory angioedema?
Vibratory angioedema generally resolves with symptomatic treatment and avoidance of physical stimuli.
The rate of complete spontaneous resolution is unknown.