What is an Allergy and why it is such a misused word ?
Millenia ago when man was developing, a vast amount of parasites existed when they entered our body they did us no good as a species so our immune system created a white mast cell to compensate. The reason for this cell was when it came across a parasite it degranulated or exploded releasing very irritant chemicals to kill the parasite. One of them is histamine hence we take antihistamine and because they are irritant and cause inflammation so we take steroids because they are anti-inflammatory . anyone suffering allergies can relate to this.
Role this on to the modern Western world we find that not as many parasites exist. Unfortunately -and we know the re is a genetic component- and now a large environmental element these cells are still looking for parasites to kill. They then turn on something which they think is a parasite. As parasites are animals and animals are high in protein they turn on high protein molecules in our blood . The most common are certain food, animal dander, house dust mites , moulds and pollen and if we can identify to what the mast cells become sensitive we have more of a chance how to control symptoms. This process is call an IgE meditative response. The NHS have two tests for this. An IgE blood test and a skin patch test. These tests can give false positives and false negatives. An example of this is when I attended a study day organised by Allergy UK I observed a lady who was known to have an allergy to egg had bloods taken and a skin prick test at the same time. The blood result was negative the skin prick test positive.
Mast cells proliferate in our body where the outside world or parasites enter our body. By breathing through our nose we cause symptoms of rhinitis, sinusitis, hay fever to present themselves together with problems associated with headache, migraine, catarrh & glue ear. Through our upper airways we can get post nasal drip, sniffing & the need to clear one’s throat whilst our lower airways can be affected by asthma & wheezing.
It has now been proven that there is a significant comorbidity between upper airway symptoms and increase in late onset of adult asthma.
Skin problems such as eczema, urticaria (rash & itch), angiodema (swelling) can affect the whole of the digestive tract. One may wonder what has my asthma got to do with my eczema or migraine – in allergy terms everything. The trouble is that with asthma you will be referred to the appropriate medical specialist for respiratory disorders, eczema to dermatology, digestive disorders to gastroenterology and your sinusitis to ENT when in fact you should be referred to immunology. It is well researched that the medical assistance in dealing with Allergy is extremely poor in this country. Sadly, our GPs are very poorly educated in Allergy.
Hypersensitivity is usually referred to wrongly as intolerance or sensitivity.
The symptoms are very similar to an IgE meditated allergic response. The difference is the mast cell are not engaged. The immune system response is on a lower level at present we have no definite proven understanding why this happens.