Anna Sanchez appears to be experiencing type I rhinitis, which is an immediate hypersensitivity. Hypersensitivity reactions are abnormal immune reactions that can manifest in various symptoms. Type I hypersensitivity is mediated by IgE and is characterized by an exaggerated response to an environmental antigen (Sobkowiak et al., 2020). Allergic reactions are the most common type of hypersensitive response.
After Anna’s initial contact with the cat, she became sensitized, meaning her B lymphocytes produced antibodies that bound to the outer surface of mast cells. Mast cells are cells of the immune system that play a key role in allergic responses. When Anna is exposed to the allergen again, before enough T cells or antibodies are present, a hypersensitive reaction is triggered (McCance & Huether, 2018).
In type I hypersensitivity, IgE binds to Fc receptors on the surface of mast cells. When the allergen is introduced, it triggers the mast cells to release histamine and other inflammatory mediators (McCance & Huether, 2018). Histamine is responsible for initiating the inflammatory process. It causes vasodilation and increases the permeability of blood vessels, leading to fluid buildup and pooling in the back of the throat and nose. This results in nasal congestion and post-nasal drip (McCance & Huether, 2018).
The release of inflammatory mediators by mast cells also leads to increased mucus production in the nasal passages. This further contributes to nasal congestion and can cause a sensation of a “stuffy nose.” The excess mucus can also drip down the throat, causing throat irritation and the urge to clear the throat frequently (McCance & Huether, 2018).
It is important to note that Anna’s vital signs are stable, which indicates that her condition is not currently life-threatening. However, her symptoms, such as nasal congestion and post-nasal drip, may significantly impact her quality of life and daily functioning.
In summary, Anna’s symptoms suggest that she is experiencing type I rhinitis, which is an immediate hypersensitivity reaction mediated by IgE. This allergic reaction is triggered by exposure to the allergen, in this case, the cat’s dander. The release of histamine and other inflammatory mediators by mast cells leads to nasal congestion, post-nasal drip, and throat irritation. While Anna’s vital signs are stable, her symptoms may still significantly impact her daily life.