Food Allergies - Exam 2 Flashcards
What is the prevalence of a food allergy? When is it most likely to show up?
Roughly 10-11% of the US population
usually in childhood, but 15% will show up as adult
What is the physiology behind a food allergy?
Inappropriate activation of the immune system, mediated by IgE**
**What antibody specifically mediates a food allergy?
IgE
______ inappropriate immunologic response to antigens in food
______ associated with problems digesting or metabolizing food
Food allergy
food intolerance
Food intolerance are prevalent is about ____ % of the US population. What is a risk factor?
15-20%
other GI disorders
Food allergy or intolerance is more likely to present in adulthood? What antibody is responsible?
food intolerance
more likely to be non-IgE, including IgG
What is the normal manifestation for a food intolerance?
symptoms based on severity correlating with dose of food ingested
GI s/s, may be uncomfortable but NOT life threatening
Food allergies are usually _____ in nature. What are the 3 MC? What are some additional ones?
protein
MC: Peanuts, tree nuts, and fish/shellfish
wheat, eggs, milk, soybeans, sesame
Name some common food intolerances?
Lactose, fructose, gluten, caffeine
**What are the 9 US legal requirements that must be listed on food labels
Peanuts, tree nuts, fish, shellfish, wheat, eggs, milk, soybeans, sesame
T/F: Only the processing line has to be âGFâ in order to put GF on the label.
FALSE, the ENTIRE facility has to be GF to put that on the label
What is the early childhood allergen exposure recommendation?
exposure children to all the things, do NOT wait, could increase risk of developing food allergy
What are some common signs of IgE food allergies?
pruritis, urticaria/angioedema, oral pruritus, sense of choking, wheezing, cough, nausea/vomiting, diarrhea
Children experiencing IgE food allergies trend towards ____ and ____ symptoms. Vs adults trend towards ____ and ____ symptoms
Children - trend towards cutaneous and GI symptoms
Adults - trend towards respiratory and CV symptoms
What is the management of IgE food allergies?
epinephrine ASAP!!
can add on: steroids, antihistamines, beta-agonists,
What is the MC form of food allergy in adults? What else will they report?
Oral Allergy Syndrome - aka Pollen-Allergy Food Syndrome
Allergens in some foods have similar molecular structure to allergenic pollen proteins
Patients typically report history of seasonal allergies, pollen sensitivity
**Describe the oral allergy syndrome? What are ways to mediate this response?
Localized, mild immune (IgE) response!
cook the foods! s/s are decrease if present at all
What are some key distinguishing factors for oral allergy syndrome? Name some s/s
Usually present after exposure to RAW fruits and vegetables. Do not have symptoms with same foods if cooked
Symptoms are restricted to oral area in about 98% of patients
Mouth - oral pruritus, swelling of oral structures
Upper Airway - hoarseness, laryngeal edema, mild stridor or sense of airway narrowing
What is the management for oral allergy syndrome?
avoid allergenic foods
Antihistamines may be helpful (Benadryl, Ranitidine)
COOK the foods!!
When would you want to work a pt up for a more serious food allergy?
Symptoms are present after tree nut or peanut exposure
Systemic symptoms are present
____ is the MC enzyme deficiency. At what age does the bodies natural level of lactase decline? What ethnicities?
Lactose Intolerance
About 5 years of age - natural levels of lactase often decline
African, Asian, Mediterranean, Native American
What ethnicity CAN tolerate lactose well?
Northern European descent
How is lactose intolerance more likely to show up in children?
more likely to have predominant diarrhea; may see bulky, frothy, watery stool
Lactose intolerance dx is often made _____. What tests can you order to confirm?
clinically!
stool studies
hydrogen breath test
small bower bx
What will the stool studies show of a pt with lactose intolerance?
increased stool osmotic gap and decreased stool pH due to undigested lactose that becomes fermented by gut bacteria
How does the hydrogen breath test work?
patient consumes solution containing lactose and serial breath samples are measured for hydrogen content
How does a small bowel bx work when trying to confirm lactose intolerance?
can be performed during endoscopy to measure presence of lactase enzyme
Non-Celiac Gluten Intolerance is present in up to ___ of US pts. Celiac Disease is present in about ___ of US populations. What ethnicity?
13%
1%
North Africa, Middle East, India, Northern China
Describe the diarrhea in pt with gluten intolerance/celiac dz?
often bulky, foul-smelling, floating stools due to steatorrhea
What are some additional s/s that are commonly associated with celiac dz?
weight loss, severe anemia, nutritional deficiencies (B vitamins, D, calcium)
T/F: Gluten Intolerance and Celiac Disease
only present with GI symptoms
False! can present with extra-intestinal manifestations
What is dermatitis herpetiformis? What intolerance is it associated with? What is a way to dx it?
looks like herpes bumps but pathology is not correct. Raised, bumpy appearance on the arms and legs
Gluten Intolerance and Celiac Disease
can do a Tzansk smear and it will show that it is NOT herpes (no giant nucleated cells)
What is the best way to dx gluten intolerance?
gluten free diet trial
serum antibody assay (pts will need to keep eating gluten until after this test is performed)
small bowel bx
What vaccination is important for Gluten Intolerance and Celiac Disease pts to have? Why?
pneumococcal vaccination
because of the extraintestinal damage that can occur to the spleen, resulting in varying degrees of functional hyposplenism. Celiac patients have been found to have a 7% higher chance of pneumonia than comparable non-Celiac controls.
