Allergic disease pollen

Chronic inflammatory response is one of the hallmarks of allergic diseases. Over the course of pollen season, there might be even a tenfold increase in numbers of nasal epithelial submucosal mast cells. Histamine released from these cells might not only induce acute allergic symptoms but also be crucial for sustaining this response into a chronic phase, as increasing evidence suggests that it influences several immune/inftammatory and effector functions (table 2) [2]. 

In general, treatment of ocular allergic disease is based on symptoms, severity, and characteristics of the allergic reaction. A stepped-care approach to therapy has been advocated, whereby treatment aggressiveness is tailored to the level of disease. When possible, avoidance of environmental allergens such as pollen, dust, and grasses is a key fector in management. 

Kemeny, D.M., Urbanek, R., Ewan, P., McHugh, S., Richards, D., Patel, S. and Lessof, M.H. (1989). The subclass of IgG antibody in allergic disease II. The IgG subclass of antibodies produced following natural exposure to dust mite and grass pollen in atopic and non-atopic individuals. Clin. Exp. Allergy 19, 545-549. 

Approximately 17% of the U.S. population suffers from some sort of allergic disease (76). Most of those individuals are hypersensitive to pollens or have atopic eczema. Six percent of the population has physician-diagnosed asthma, the prevalence of which has increased by approximately 30% over the last 15 years. Air pollution exposure has long been considered a risk factor for the exacerbation of asthma attacks in asthmatic individuals. Health care statistics in Canada and the United States show that hospital admissions for asthma increase dur-... 

The large body of epidemiological studies have clearly shown that allergic rhinitis and asthma are frequent diseases, and that both diseases obviously still increase in prevalence [4, 5]. However, without any doubt, there is a direct link between rhinitis and asthma. Several studies in a large number of patients have clearly shown that rhinitis sufferers have a 3- to 7-fold increased risk to also develop asthma within 7 years compared to normal controls. Most of this development actually lies in the early years of childhood, as was recently shown in the MAS and PAT studies [6, 7], In the first study, 5-year-old children sensitized to pollen with allergic rhinitis symptoms developed asthma within 2 years... 

Atopy refers to the allergic sensitivity that certain individuals develop towards common and mostly innocuous environmental antigens such as dust mites, plant pollens and animal proteins. The condition of atopy generally manifests itself clinically in the form of asthma, hay fever, eczema or allergic rhinitis. The development of an atopic condition has been associated with the generation of predominately Th2 biased immune response to the particular allergen, and is thus often referred to as a Th2 based disease (Romagnani, 1994). 

Hay fever is most commonly due to hypersensitivity to pollens (tree pollen in springtime, grass and weed pollen during the summer) and occasionally mould spores (during the late summer and autumn months). There is a strong link between allergic rhinitis and other immune-mediated diseases such as atopic eczema and asthma. 

The effectiveness of immunotherapy for seasonal allergic rhinitis appears to be better than that seen with perennial rhinitis, in part because it is more difficult to determine which allergen is responsible for perennial symptoms, and it is more due to multiple sensitizations. Effectiveness has been shown in a number of clinical studies using a variety of pollen extracts, even in patients with severe disease resistant to pharmacotherapy." " Specific immunotherapy for house dust mites has had good results in appropriately selected patients, while several studies have described marked improvement in patients with allergy to cats. Data indicate that in some patients 3 years of immunotherapy may be sufficient to give lasting benefit." ... 

---