Vibratory Urticaria

Vibratory Urticaria
Vibratory Urticaria

Overview Of Vibratory Urticaria

Vibratory Urticaria (VBU) is a condition that starts from exposing the skin to vibration or repetitive action. This then causes allergy-like symptoms, like redness, swelling, hives, and itching in an affected area. 

This can emerge from drying with a towel, hand-clapping, running, or any other repetitive action on an area. This reaction happens within a few minutes of stimulation and generally lasts up to an hour. People with this condition can have several episodes per day. Some symptoms include a  metallic taste in the mouth, faintness, blurry vision, headaches, fatigue, facial flushing, and more wide facial swelling in the face.

Commonly Associated With

  • dermo distortive urticaria
  • vibratory angioedema

Causes Of Vibratory Urticaria

Vibratory urticaria arises from a mutation in the ADGRE2 gene. This gene provides instructions for making a protein found in several types of immune system cells, including mast cells. Mast cells arise in many body tissues, like the skin. These are important because they have normal protective functions of the immune system. They also play a role in allergic reactions, which occur when the immune system overreacts to stimuli that are not harmful. The ADGRE2 protein’s specific role in mast cells is unknown.

Vibratory urticaria originates from a mutation in the ADGRE2 gene. This gene gives orders for creating protein in several types of immune system cells, including mast cells. Mast cells are then found through body tissues like the skin, are important normal immune protection. These also have a role in creating allergic reactions, because allergies happen when the immune system overreacts to unharmful stimuli. The specific role of the ADGRE2 protein in mast cells is largely unknown.

The ADGRE2 Protein’s Importance in UVB

The ADGRE2 protein consists of two parts that are subunits which interact with each other. An alpha subunit lies on the outside surface of the cell and a beta subunit that crosses the cell membrane and pushes into the cell. The ADGRE2 gene mutation that causes vibratory urticaria changes a single amino acid (a protein building block) in the alpha subunit. This will then change the protein structure and begins a less stable interaction in these two subunits. The connection between subunits is fragile and can be easily broken by friction, vibration, or stretching skin. Because each of these can disrupt the subunits in mast cells. 

Current research argues that separated subunits signal the mast cells to react and produce an allergy symptoms in the skin from vibratory urticaria. However, some people with vibratory urticaria do not have a mutation in the ADGRE2 gene. Because of this, this version has an unknown cause.

Other Information On Vibratory Urticaria

VBU is a rare condition. It is classified as a physical urticarias. These arise when allergy symptoms are acted by exposure to things like heat, coldness, sunlight, or pressure. Physical urticarias happen in up to 5 in 1,000 people. 

This disorder is also a dominant autosomal pattern. This means one of these irregular genes, passed from a parent, in a cell is enough to bring on the condition.