Allergies (Slides) PDF

## Allergies (SLIDES) ### What is an Allergy? - Immune response to antigen - Antigen = unrecognized substance, often a protein 1. initial exposure: immune cells attack, destroy, create antibodies (Smurf soldiers) 2. immune system has a memory! 3. subsequent exposure: swift physical rea...

## Allergies (SLIDES) ### What is an Allergy? - Immune response to antigen - Antigen = unrecognized substance, often a protein 1. initial exposure: immune cells attack, destroy, create antibodies (Smurf soldiers) 2. immune system has a memory! 3. subsequent exposure: swift physical reaction as antigen is eliminated - Symptoms - mild GI discomfort - lip, tongue, throat: tingling or swelling - skin rashes: hives or eczema - abdominal pain, diarrhea, nausea, vomiting - anaphylaxis ### Food Allergy vs. Intolerance | Allergy | Intolerance | |---|---| | immediate hypersensitivity reaction | delayed hypersensitivity reaction | | symptoms within minutes of ingestion up to 2 hours (IgE); or, up to several days (non-IgE) | symptoms within 48-72 hours | | IgE- and non-IgE-mediated (immune system) | cell-mediated (non-immune) | | usually very low or no intake threshold | small amounts may be tolerated | | reactions vary - mild to life-threatening | reactions include discomfort, but rarely life-threatening | | examples: milk allergy, peanut allergy | examples: lactose, Celiac Disease (gluten intolerance) | ### Food Allergies: Protein - 8% of children and 3-10% of adults have food allergies - Top Eight account for 90% of food allergies 1. MILK 2. EGGS 3. WHEAT 4. SOYBEANS 5. PEANUTS 6. Tree nuts (like almonds, cashews, walnuts) 7. Fish (like bass, cod, flounder) 8. Crustacean shellfish (like crab, lobster, shrimp) - Least likely to outgrow by adulthood - Most likely to outgrow by adulthood - **BOLDED CAPS** - most prevalent food allergies in U.S. ### Food allergies - Almost 2.5% of children (21% increase since 2010) - **very dangerous for those who ARE allergic!** - Introducing peanut foods early (4-6 mo) to high-risk infants can reduce the risk of developing peanut allergies by up to 86% - those with severe eczema and/or egg allergy - Speak with pediatrician about plan to introduce peanuts early ### Food allergies: prevalence - Estimated lifetime prevalence of any allergy in U.S. = up to 1:5 - Females > males - Causes?... Environment - hygiene, early or delayed exposure - **Developing countries** - Large family size - Rural homes, livestock - Intestinal microfora variable, transient - Low antibiotic use - High helminth burden - Poor sanitation, high orofaecal burden - **Westernized' countries** - Small family size - Affluent, urban homes - Intestinal microflora stable - High antibiotic use - Low or absent helminth burden - Good sanitation, low orofaecal burden This image shows a bar chart. It compares the prevalence of food allergies in children less than 3 years old and adults, comparing allergies to: Milk, Eggs, Peanuts, Tree nuts, Fish, and Shellfish. The bar chart shows that peanuts have the highest rate for both children and adults. The second highest rate for children is tree nuts, while the second highest rate for adults is milk and eggs with almost equal rates.