Immediate hypersensitivity is a form of allergic reaction which develops very quickly, namely within seconds or minutes of exposure of the patient to the causative allergen. This immediate reaction can be followed by a second reaction of delayed onset that can lead to inflammatory changes in the target organ and manifests itself by chronic symptoms such as asthma or atopic dermatitis.
Immediate hypersensitivity is mediated by antibodies belonging mainly, but not exclusively, to the IgE isotype. IgE antibodies bind to specific receptors on cells such as basophils, mastocytes or Langerhans' cells. Upon allergen exposure, surface-bound IgE transduce a signal into the cell, which is followed by cell activation, which in the case of basophils and mastocytes is accompanied by the release of preformed mediators such as histamine and enzymes, and the synthesis of metabolites of arachidonic acid. These mediators are responsible for the development of allergic signs and symptoms, such as bronchospasm, vasodilatation, hypersecretion of mucus and stimulation of sensory nerve ends resulting in pruritus.
IgE antibodies are produced by B lymphocytes that received appropriate activation signals. Full description of the mechanisms by which IgE antibodies are produced can be found in appropriate reviews.
Current treatment of allergic symptoms include allergen avoidance, drug therapy and immunotherapy. Complete avoidance from allergen exposure is the most logical approach, but it remains very difficult, or impossible to achieve in a vast majority of cases. Drug therapy is useful, but alleviates the symptoms without influencing their causes. In addition, drug treatment is usually limited by undesirable side-effects.
We offer hyposensitisation therapy:
1) conventional hyposensitisation which is a treatment consisting in administering to the patient progressively increasing doses of the allergen(s) to which he has developed a sensitivity which is what we offer in our clinic.
The allergens are mostly: - house dust mites allergens obtained from Dermatophagoides spp. pteronyssinus, farinae and microceras, Euroglyphus maynei or Blomia,
- allergens from pollen, especially pollens of tree, grass and weed.
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