Reactions and Allergies

The word allergy comes from two Greek words: "allos" meaning other and "ergon" meaning work. Allergic reactions are abnormal over-reactions by the immune system to harmless, protein substances called allergens, which are contacted through the skin, inhaled or injected. An allergen is a substance that causes an allergy.

Common Allergens:

• Animal dander. This is material shed from the body such as feathers, dried skin, hair and feathers)


• Bee stings


• Foods, especially nuts, fish, shellfish


• Insect bites


• Medications


• Plants


• Pollen.

Causes:

Allergic reactions can be caused by two main factors: host factors or environmental factors.

Host factors:

• Hereditary; the likelihood of developing an allergy is inherited but the specific allergen to which you are allergic is not inherited.


• Sex: boys are at a higher risk of sensitivity than girls (except in the case of asthma).


• Race, although this may be as much to do with to environmental factors as race itself.


• Age: younger children are at greater risk of sensitivity.

Environmental factors:

• Exposure to infectious diseases in early childhood


• Pollution


• Allergen levels


• Dietary changes

Symptoms:

• Skin:




• Redness


• Itching


• Inflammation


• Blistering


• Weeping


• Crusting


• Rash


• Eruptions


• Hives (which are itchy bumps or welts)


• Lungs:


• Wheezing


• Tightness


• Chest discomfort


• Difficulty breathing


• Difficulty swallowing


• Coughing


• Shortness of breath




• Head:


• Swelling of face, eyelids, tongue, lips and throat


• Redness


• Headaches


• Dizziness or light-headedness


• Weakness


• Anxiety, apprehension or fear


• Nose:


• Blocked or stuffy nose


• Nasal congestion


• Runny nose


• Sneezing


• Eyes:


• Red and bloodshot


• Itchy


• Swollen


• Watery


• Stomach:


• Pain


• Cramps


• Nausea


• Vomiting


• Diarrhoea


• Bloody Diarrhoea


• Severe reactions:


• Unconsciousness


• Anaphylaxis


• Shock

In severe cases anaphylaxis can occur and this requires immediate medical attention. It is a combination of other allergic symptoms that appear rapidly and are potentially life-threatening. It can induce shock; one sign of shock is that organs don't get enough blood, and therefore oxygen and nutrients, due to very low blood pressure. The person may appear red or pale, sweaty or dry, confused, anxious or they may be unconscious. The person also has difficulty breathing. Anaphylactic shock is caused by sudden dilation or widening of many, or several large, blood vessels brought on by the action of chemical mediators. A sudden drop in blood pressure can lead to unconsciousness, cardiac arrest or death.

At the moment there is a theory called the hygiene hypothesis which has been "extensively investigated by immunologists and epidemiologists". It involves the idea that people who live in too sterile environments are not exposed to enough pathogens to keep their immune system busy so it over-reacts to normally harmless substances. There is some evidence to show that allergic diseases are more common in industrialised countries or urban areas rather than more traditional agricultural countries or rural areas. Also, using antibiotics to treat babies under 1 year old has been linked to an increase in asthma and other allergies, as has the use of antibacterial cleaning products.

The Immune Response:

In an allergic reaction the immune system recognises the particles (such as dust or pollen) as foreign and initiates a two-phase immune response. The first phase is called the acute response and occurs immediately after exposure to the allergen. T-lymphocyte cells, which are white blood cells involved in immune response, recognise the allergen as foreign and produce cytokines (these are similar to hormones and are involved in cellular communication). Cytokines stimulate another type of white blood cell, called B-lymphocytes, to produce specific antibodies (antibodies are proteins with a variable region that has a complementary shape to a specific antigen). In allergic reactions the specific antibody is called immunoglobulin E or IgE. IgE binds to special IgE receptors on mast cells and basophiles. Mast cells are found in connective tissues while basophiles circulate in the blood; both are involved in inflammatory responses. This first stage is known as sensitisation because the body is now sensitive to a particular, normally harmless, particle. Therefore when the body encounters the substance again, the allergen (substance) binds to the IgE which is on the surface of mast cells and basophiles. This activates the mast cells and basophiles to release histamine, from stores known as granules, into surrounding tissues. Histamine causes:

• Blood vessels to dilate so blood pressure drops.


• Stimulates glands in the nose and respiratory passages to produce mucous, also known as phlegm.


• Mucous membranes, which line the nose and respiratory passages, to swell because fluid leaks out of the blood vessels.


• It stimulates nerves.


• Smooth muscle contraction. (In asthma the muscles surrounding the windpipe contract narrowing the airways and increasing the resistance to air flow so breathing is difficult.)

The second phase in the immune response is called the late-phase response. This normally occurs 2-24 hours after the acute response, once the chemical mediators such as the cytokines, have subsided. The chemicals released earlier by the mast cells attract other types of inflammatory immune cells including neutrophils, lymphocytes and macrophages, to the site. These produce chemicals and other, generally toxic, substances that irritate the body. Neutrophils also release chemicals and enzymes which break down proteins causing further tissue damage.

Treatment:

For mild cases:

First aid can be administered before further medical help arrives. This includes:

- Calming and reassuring the person: anxiety can often worsen symptoms.
- Identifying the allergen and if possible removing it and avoiding further contact.
- Applying calamine lotion, a cool compress or cortisone cream to rashes.

Oral antihistamines can be taken but these have adverse side effects including making you drowsy and affecting your concentration so you aren't allowed to drive or operate machinery if you are on them. They should only be taken for a few days. For rashes anti-inflammatory steroid cream or cold wet cloths can be applied to cool the area.

For severe cases:

Emergency medical help should be sought, don't wait to see if the symptoms worsen, because they can worsen very rapidly so it is better to get medical attention as quickly as possible. Again first aid can be administered while you wait for further help to arrive:

- If they are unconscious use DR. ABC. This stands for danger, response, airways, breathing, and circulation.
- Danger: First check that you aren't endangering yourself or the other person. Remove any dangerous objects that may be around.
- Response: Call their name and introduce yourself (even if the person knows you well) watch for any response either verbal or movement.
- Airways: Check that their airway is clear, removing any objects that may be obstructing the airways (such as chewing gum), tilt the head back slightly to open the airways.
- Breathing: Check that the person is breathing by placing your head close to their mouth and nose, listening and feeling for breath or moisture. If they aren't breathing then you should begin mouth to mouth resuscitation by pinching their nose and placing you own mouth over theirs creating a seal, then breathe hard into their mouth.
- Circulation: To check that the person's heart is still beating, find the pulse in their neck which should be just to the side of the windpipe. If there is no pulse begin Cardiopulmonary resuscitation (CPR) by doing chest compressions to try to pump the heart. (If they aren't breathing either include breaths as well)
- If the person is awake calm them and reassure them.
- Identify and remove the allergen where possible.
- Administer emergency medication if the person has it, for example an auto-injector with a pre-measured dose of the drug epinephrine (Epipen)
- To treat shock lie them flat (unless it causes discomfort or makes breathing difficult) and raise the person's feet, keep them warm.

Medical treatment for severe allergic reactions may include providing oxygen support or even artificial ventilation. Also fluids may be injected in to veins (intravenously-IV) to help raise the blood pressure.

For more long-term treatments antihistamines can be prescribed such as cetirizine (Zyrtec), fexofenadine (Allegra) and loratadine (Claritin). Nasal corticosteroids can be prescribed for persistent nasal symptoms; these include fluticasone (flonase), mometasone (Nasonex) and triamcinolone (Nasacort). For more severe cases Epinephrine can be injected as this acts as a bronchodilator (it widens the bronchus and bronchioles which are part of the windpipe). Epinephrine also constricts blood vessels so blood pressure increases. Inhalers can also be prescribed and antihistamines can be given intravenously or intra-muscularly to counter the histamine that the body has produced. Corticosteroids can be given intravenously for a rapid reversal of the effects of the chemical mediators produced by the body.

For people with persistent or disruptive allergy symptoms immunotherapy can be given. Immunotherapy reduces the severity of the reaction or eliminates hypersensitivity altogether. There are several different methods of immunotherapy:

1. Allergy shots. These alter the immune response which prevents future reactions. They are administered as a series of shots containing increasing amounts of the specific antigen to which the person is allergic. The person should then become desensitised.


2. Another method is to progressively distort the production of another antibody called Immunoglobulin G which blocks the excessive Immunoglobulin E production. This means that the person builds up increasing immunity to increasing amounts of the allergen.


3. Intravenous injections can be given, containing monoclonal anti-IgE antibodies. Monoclonal antibodies are antibodies against one specific antigen produced by a cloned hybridoma cell. (Hybridoma cells are B lymphocyte cells fused with myeloma cells) These monoclonal anti-IgE antibodies bind to free and B-lymphocyte-associated IgE, which signals their destruction. They don't bind to IgE that is already on mast cells as this would stimulate an allergic reaction.


4. Sublingual immunotherapy. This can be administered orally and it takes advantage of oral immune tolerance to non-pathogenic antigens such as food and bacteria. In other words the immune system doesn't attack these antigens.

Prevention:

One of the best ways to prevent allergic reactions is to identify what triggers them and then avoid or remove the triggers as much as possible.

Tests:

Skin tests: These tests are more sensitive, simpler and cheaper than blood testing. It involves exposing the skin to small amounts of various substances, or suspected allergens and assesses the presence of IgE antibodies. The substance can be injected intradermally (into the skin). If you are allergic to that substance then a visible inflammatory reaction occurs within 30 minutes. There is a scale of severity where +/- means borderline reactivity and +4 means a large reaction. These tests are usually carried out on the forearm or the back.

Blood tests:
Blood tests measure the total IgE level by estimating the amount of IgE in the serum.

Allergic Reactions due to body piercings:

People can get allergic reactions from body piercings for two reasons: they are allergic to the metal or they are allergic to a product used as part of aftercare treatment.

Metal allergy due to inferior jewellery:
Symptoms include:

• Redness


• Itchy


• Burning


• Tender


• Highly inflamed around the piercing


• Localised dermatitis


• Granulation tissue where visible


• Opening of the piercing appears significantly larger then the jewellery


• The tissue around the piercing appears to retreat from the piercing.

This can be treated by using biocompatible jewellery such as Titanium or a low-porosity plastic like Tygon or PTFE.

Often the jewellery can cause problems because it is poor quality or you are sensitive to it and have allergic reactions. If you catch an infection then you must eliminate the reservoir which is often the jewellery. Cheap nickel or brass commonly triggers allergic reactions and in some cases antibiotics may be needed. Alloys of gold, copper, silver and trace metals can also be irritating and prevent complete healing, therefore it may be better opting for more expensive but good quality jewellery such as titanium which is inert and used in internal surgery although it must be highly polished to reduce its porosity. Implant grade stainless steel is good as well because it is least likely to produce an allergic reaction or an infection. The implant grade stainless steel must be approved by ASTM and meet standard 316L and 316LM.

The American Society for Testing Materials or ASTM was originally set up 100years ago by engineers to standardise steel used in railways. Now it is used for standardising many other things as well. A standard is a document which is developed and established within consensus principles of an organisation which meets the requirements of ASTM procedures and regulations. It is usually developed by the people who have a stake in the standard's development or use. The International Organisation for Standardisation (ISO) is the European equivalent of ASTM. "Isos" is also the Greek word for equal which is also why it is called ISO as the actual words translate differently in different languages. Standards ensure desirable characteristics of products and services such as quality, environmental friendliness, safety, reliability and efficiency. It is recommended that titanium used in jewellery should meet ASTM standard F67, F136 or better, whereas steel should meet ASTM F138, F1537 or better and it should only be worn temporarily and only in healed piercings. 24 karat gold and platinum alloyed with Iridium or Ruthenium are biologically inert but they are heavy, soft and easily scratched and damaged. 18 Karat gold (75% gold) can be used in new piercings and 14 karat gold in healed ones, but gold-filled or plated jewellery should be avoided as the metal is thin and wears away or is chipped easily. Silver is bad as it tarnishes and can be deposited so that it permanently darkens and stains the skin. However, sterling silver is OK in most piercings but not in places where the skin is moist such as the mouth or genitals.

Product allergy:

Symptoms:

• Delayed healing


• Localised irritation


• Redness


• Localised dermatitis


• Seeping


• Expansion of piercing channel

To treat this you should stop using the aftercare or your current care regime and use a milder product with less aftercare.