Transcript lecture 5x
May be I am allergic to flowers Allergens Introduction Hypersensitivity (hypersensitivity reaction) refers to undesirable immune reactions produced by the normal immune system. Allergies are hypersensitivities It is overreactions of the immune system to substances that do not cause reactions in most people. Allergen (Substances that often cause reactions)also called antigen that causes allergy. Antibody Types • • • • • Immunoglobulin G (IgG) Immunoglobulin A (IgA) Immunoglobulin M (IgM) Immunoglobulin E (IgE) Immunoglobulin D (IgD) Antibodies (2 of 3) • IgG – Smaller antibody – Principal antibody molecule in response to majority of infectious agents • IgM – Large antibody, a macroglobulin – Very efficient combining with fungi • IgE – Found in minute quantities in blood; concentration is increased in allergic individuals Antibodies (3 of 3) • IgA – Produced by antibody-forming cells located in the respiratory and gastrointestinal mucosa – Combines with harmful ingested or inhaled antigens, forming antigen-antibody complexes that cannot be absorbed, preventing antigens from inducing sensitization • IgD – Found on cell membrane of B lymphocytes – Present in minute quantities in blood Hypersensitivities are grouped into four types, I through IV. Based on what parts of the immune system are activated and how long it takes for a reaction to occur. • Atopy is the inherited propensity to respond immunologically to such common naturally occurring allergens with continuous production of IgE antibodies. Gel and Coombs classification of hypersensitivities. Type I Type II Type III Type IV IgE Mediated IgG/IgM Mediated IgG Mediated T cell Immune complex Disease Delayed Type Hypersensitivity Classic Allergy rbc lysis Introduction two types of hypersensitivities commonly associated with allergies: Type 1 and type 4 type I (immediate hypersensitivities) in which antigens (allergens) combine with specific IgE (immunoglobulin E) antibodies to cause local and sometimes systemic reactions – usually within minutes Introduction The first time a predisposed person (FH) is exposed to a potential allergen, they will not have a major reaction; instead, they will create a specific IgE antibody and become “sensitized. ” The IgE antibody produced then attaches itself to mast cells, in the tissues, and basophils in the blood stream. Mechanism of type I hypersensitivity Allergen Primary Individual Generation IgE Adhesion Secondary IgE binds to the FceRI on mast cell and basophil Allergen binds to the IgE on primed target cell Crosslikage of FceRI Degranulate and release the biological mediators Preformed granule mediators Histamine Bradykinin New generated mediators Leukotrienes PAF Prostaglandin D2 Dilate capillaries,increase permeability, increase mucus secretion, contract smooth muscle Systemic anaphylaxis Skin Respiratory tract Degist tract Introduction type IV (delayed hypersensitivities) reactions caused by the interactions of antigens with specific sensitized T lymphocytes instead of antibodies. Type IV delayed hypersensitivity reactions are most often skin reactions. Common examples include reactions to metal and jewelry. Introduction They occur when an antigen interacts with specific sensitized T lymphocytes. The lymphocytes release inflammatory and toxic substances, which attract other white blood cells to the exposure site, resulting in tissue injury. Type IV hypersensitivity is usually a reaction (redness, swelling, hardening of the skin, rash, dermatitis) observed at the exposure site hours to days after exposure Types of Allergens Types of Allergens There are many different types of allergens that could trigger an allergic Pollen Animals Dust Mites Foods (Egg, Milk, Peanut, Shellfish, Soy, Tree nut, Wheat, Banana and strawberries) Insect Stings Latex Mold Allergens Sulfonamide drugs salicylate Penicillins Allergy symptoms depend on route of allergen entry Dust or pollen are airborne particles. In these cases, symptoms arise in areas in contact with air, such as eyes, nose and lungs. For instance, allergic rhinitis, also known as hay fever, causes irritation of the nose, sneezing, and itching and redness of the eyes. Inhaled allergens can also lead to asthmatic symptoms, caused by narrowing of the airways (bronchoconstriction) and increased production of mucus in the lungs, shortness of breath (dyspnea), coughing and wheezing Symptoms of food allergy include abdominal pain, bloating, vomiting, diarrhea, itchy skin, and swelling of the skin during hives. Food allergies rarely cause respiratory (asthmatic) reactions, or rhinitis. Substances that come into contact with the skin, such as latex, are also common causes of allergic reactions, known as contact dermatitis or eczema. Skin allergies frequently cause rashes, or swelling and inflammation within the skin. Insect stings, antibiotics, and certain medicines produce a systemic allergic response that is also called anaphylaxis; multiple organ systems can be affected, including the digestive system, the respiratory system, and the circulatory system. Depending of the rate of severity, it can cause cutaneous reactions, bronchoconstriction, edema, hypotension, coma, and even death. This type of reaction can be triggered suddenly, or the onset can be delayed. The severity of this type of allergic response often requires injections of epinephrine, sometimes through a device known as the EpiPen or Twinject auto-injector. Treatment of Allergy The three most effective ways to treat allergies are 1- Avoidance 2- Immunotherapy 3- Medication. 1- Suggestions for avoiding (some) allergens: Remain indoors when the pollen count is high and on windy days. Dust-proof the home, particularly your child's bedroom. Eliminate, when possible, wall-to-wall carpet, Venetian blinds, and down- filled blankets or pillows. Wash bedding, curtains, and clothing often and in hot water to eliminate dust mites. Keep bedding in dust covers, when possible. Use air conditioning instead of opening the windows. Consider putting a dehumidifier in damp areas of the home, but remember to clean it often. Have your child wear a face mask if playing outside when the pollen count is high. Take vacations in areas where pollen is not as prevalent - such as the ocean. 2- Immunotherapy (allergy Shots) Immunotherapy is a type of treatment for allergic children with hay fever and/or asthma. It is also called desensitization, hyposensitization, and allergy shots. A mixture of the various pollens, mold spores, animal dander's, and dust mites to which the child is allergic is formulated. This mixture is called an allergy extract. Immunotherapy is given by injection under the skin usually into the fatty tissue in the back of the arm. Injections may be given weekly or twice a week until a maximum dose is tolerated. This is called the maintenance dose. It may take about one year to reach the maintenance dose. At this point, the frequency of injections may be decreased to every other week and finally to once a month. Side effects to immunotherapy There are two types of reactions to immunotherapy: Local: The local reaction is redness and swelling at the injection site. If this condition occurs repeatedly, then the extract strength or schedule is changed. Systemic reaction is one that involves a different site, not the injection site. The symptoms may include nasal congestion, sneezing, hives, swelling, wheezing, and low blood pressure. Such reactions can indeed be serious and life threatening. However, deaths related to immunotherapy are rare. If a systemic reaction occurs, your child may continue taking shots, but of a lower dosage. Desensitization (immunotherapy,“allergy shots”) is sometimes recommended if the allergen cannot be avoided and not poten. It includes regular injections of the allergen( for 3 years), given in increasing doses that may “acclimatize” the body to the allergen. The shots cause the body to make a protective antibody ( IgG) can trigger anaphylaxis. Immunotherapy is not recommended for food allergens 3- Medication 1- Mast cell stabilizer. 2- Histamine receptor antagonists 3- Leukotriene inhibitors 4- Corticosteroids Blood testing This kind of testing measures a "total IgE level Skin testing preferred over blood allergy tests because it is more sensitive and specific, simpler to use, and less expensive. also known as "puncture testing" and "prick testing" due to the series of tiny puncture or pricks made into the patient's skin. Small amounts of suspected allergens and/or their extracts (pollen, grass, mite proteins, peanut extract, etc.) are introduced to sites on the skin marked with pen or dye. If a serious life threatening anaphylactic reaction has brought a patient in for evaluation, some allergists will prefer an initial blood test prior to performing the skin prick test. Skin tests may not be an option if the patient has widespread skin disease or has taken antihistamines sometime the last several days. Diagnosis Food allergy The common allergens are: peanut egg milk fish crustaceans soy gluten Wheat sesame tree nuts walnuts, almonds, cashews, pistachios Food allergy symptoms can include one or more of the following: Hives, rash, tingling of the mouth or throat, abdominal cramps, vomiting, diarrhea, swelling of the face or tongue, or difficulty breathing. People with the same food allergy may have different reactions. Food allergies can be fatal For your information Peanut Allergies: Hidden Ingredients Arachis oil Ground nuts, ground peanuts Imitation walnuts or almonds Mixed nuts* Mixed nut butters Nut butters* Nut extracts* Nut flavorings* Peanuts * May contain peanuts Peanut butter Peanut butter chips Peanut extract Peanut flavoring* Peanut flour Peanut oil Ground nut oil Peanut syrup Satay sauce* Tree Nut: Hidden Ingredients Almonds Brazil nuts Cashews Chestnuts Filberts/hazelnuts Gianduja* Hickory nuts Macadamia nuts Marzipan/almond paste Nougat Nu-Nuts ® artificial nuts * Gianduja is a creamy mixture of chocolate and chopped nuts found in premium or imported chocolate Nut butters (cashew butter) Nut milks (almond milk) Nut oil Nut paste (almond paste) Pecans (Mashuga nuts) Pine nuts Pistachios Pralines Pure almond or other nut extract Walnuts Wheat Allergy – Hidden Ingredients Bleached all-purpose flour Bran Bread, bread crumbs Bulgur wheat, Durum wheat Cake and pastry flour Cereal extracts, cereal binder, cereal filler, cereal protein Cracker meal Cream of Wheat ® Malt-O-Meal ® Couscous Durum Enriched flour, bread flour (white or wheat) Farina Flour, granary flour Gliadin Gluten Grain-based coffee substitutes Graham cracker, graham flour Hydrolyzed protein Hydrolyzed vegetable protein Instant soup stock Modified food starch MSG (Monosodium glutamate) Pasta, noodles Puddings, wheat thickeners Soy sauce Spelt, Triticale Wheat Allergy – Hidden Ingredients Vegetable starch Vitamin E pills (some) Wheat flour and wheat bran Wheat germ, wheat starch Wheat gluten, gluten flour Wheat semolina, semolina flour White (grain) vinegar •Oats, barley, rye, triticale, and spelt may also cause problems for people with gluten sensitivity. •Buckwheat is an herb and does not contain gluten. www.gluten.net PLEASE NOTE: •Stabilizers, spices and emulsifiers can also indicate the presence of wheat •Some alcoholic beverages (beer, whisky and gin) may cause allergic reactions in individuals with wheat allergies. Egg Allergy – Hidden Ingredients Albumin Apovitellin Batter Cholesterol-free eggs Custard Dried egg Egg, egg glazes Eggnog Egg noodles Egg white solids Egg yolks Globulin Lecithin (could be derived from soy) Livetin Lysozyme Marzipan Mayonnaise Meringue Mouse Ovalbumin Ovamucoid/ovamucin Ovovitellin/vitellin Powdered or liquid eggs Pudding Quiche Simplesse Souffle Milk Allergy: Hidden Ingredients Bechamel sauce Butter, butter solids Butter fat Butter flavor Buttermilk Casein Caseinates Cheese (any kind) Cottage cheese Cream Curds Custard Dried milk solids Evaporated milk Ghee Half-and-half High protein flour Ice cream, ice milk Lactate solids Lactoglobulin, lactalbumin Lactose Malted milk Margarine Milk (any kind, except soy) Milk protein Milk solids Non-fat dry milk Nougat Pudding Rennet Sodium casein Sour or whipping cream Whey Yogurt (any kind, except soy) Soy Allergy: Hidden Ingredients Edamame soy bean Hydrolyzed soy protein Lecithin Miso Modified food starch Natto Shoyu sauce Soy albumin Soy beans (curds, granules) Soy concentrate Soy cheese Soy flour Soy grits Soy meat, soy meal Soy milk, soy ice cream Soy nuts Soy oil Soy protein concentrate Soy protein isolate Soy sauce Soy sprouts Soy yogurt Tamari Tempeh Textured soy protein (TSP) Textured vegetable protein (TVP) Tofu Soy Allergy: Hidden Ingredients The following are label ingredients that may contain the presence of soy protein: Hydrolyzed plant protein Hydrolyzed vegetable protein Natural flavoring •Vegetable broth •Vegetable gum •Vegetable starch Many gluten free products contain soy. Check the label. Fish/Shellfish Allergy: Hidden Ingredients Albone Clams (cherrystone, littleneck, Mussels Worcestershire sauce (may contain pismo, quahog) Cockle (periwinkle, sea urchin) Crab Crawfish (crayfish, ecrevisse) Fish oil capsules Fish broth or stock Lobster (langouste, langoustine, coral, tomalley) Mollusks Parvalbumin is the protein in fish that is known to provoke allergic reactions. anchovies) Octopus Oysters Prawns Scallops Scampi Shrimp Snail Squid (calamari) Sushi Fish/Shellfish Allergy: Hidden Ingredients The following ingredients may indicate the presence of protein: Bouillabaisse Fish stock Seafood flavoring (crab or clam extract) Surimi shellfish Corn Allergy: Hidden Ingredients Baking powder* Cereals Confectioner’s (powdered) sugar Corn – ANYTHING! Dextrin or maltodextrin Dextrose, glucose, or fructose Golden syrup (treacle) Glucona delta lactone High-fructose corn syrup Hominy, grits Invert sugar, invert syrup Malt, malt syrup, malt extract Modified food starch (may be corn) *Do not confuse with baking soda. Baking powder contains a mixture of leavening agents and a moisture-absorber such as cornstarch. Mono- and diglycerides Monosodium glutamate (MSG) Polenta Sorbitol Starch, food starch Sucrose (may derive from corn) Vanilla extract Vegetable oil (may be corn) Xanthan gum Zein (protein from corn, sometimes used in time-released medications) Substitutions for Corn Featherweight Baking Powder or Arrowroot Latex Allergies Proteins found in these items have a similar chemical composition to latex and a reaction may occur from consuming these foods: Banana Avocado Chestnut Hazel Nut Kiwi Melons Passion Fruit Fig Tomato Carrot Celery Papaya Potato Pineapple Mango Peach Substitutions for Wheat Products Rice flour Tapioca flour Cornstarch Potato Starch Flour Soy bean flour Arrowroot Cornmeal Corn flour Gluten Free Mix 6 cups of rice flour, 2 cups of potato starch flour, 1 cup of tapioca flour. Combine, store in a cool, dry place for use as needed. Makes 9 cups. Milk Substitutions Baked goods containing soy, rice or almond milks Cornstarch puddings made with fruit juice Frozen tofu desserts Milk-free margarine (parve), salad dressings (almond milk) Milk-free sherbets, ices and sorbets (Alpine Ice) Milk-free or soy milk shakes Nut, soy or rice milks Soy cheese and soy yogurt Some non-dairy creamers Egg Substitutions For each egg, try one of the following: 1 packet of plain gelatin mixed with 2 tbsp warm water. Mix into other ingredients immediately before it thickens. 1 tsp. baking powder, 2 tbsp. Vinegar 1 tsp. yeast dissolved in ¼ cup warm water 1 tbsp. apricot puree 1 ½ tbsp. water, 1½ tbsp. cooking oil, & tsp. baking powder Egg Replacer, such as Ener-G® tbsp. powder and 2 tbsp. water 1 1/2