Dermatology

Question 1

Food allergy

Answer 1

• Immunologically mediated, adverse reaction to an
  ingested protein / glycoprotein (allergen) [Beef, dairy products, fish, wheat …..]
• Ability to induce hypersensitivity depends upon size & structure of protein
• Molecular weight 10,000 to 70,000 Daltons stimulates immune response
• Common dietary protein allergens: 18,000-36,000 Daltons

Question 2

The immune system comes in contact with food allergen via

Answer 2

skin, inhalation, alimentary tract

Question 3

Antigen protection

Answer 3

GI acids, mucous layer, intact epithelial cells, digestive enzymes, bile salts, Ig A

Question 4

Breakdown of natural defense systems

Answer 4

• Maldigestion
• Inflammatory mucosal disorders
• T-suppressor cell dysfunction

Question 5

Clinical signs of food allergy

Answer 5

• Onset: 4 months – 14 years old
• Non-seasonal pruritic dermatitis, otitis externa,
  intermittent vomiting, diarrhea, colitis, borborygmus
• GI symptoms only in 10-15% of the cases
• 20-30% cases have concurrent hypersensitivities!!

Question 6

Feeding management: novel protein/CHO strategy

Answer 6

• Duck, rabbit, venison, buffalo, kangaroo, fish…….

- Potato, barley, oats

Question 7

Feeding management: modified protein strategy

Answer 7

• Hydrolyzed isolated soybean, chicken liver, casein
• Small peptides, ideally <5,000 Daltons to minimize allergenicity
• Highly digestible protein source
• Starch, corn starch

Question 8

Feeding management: limited antigen exposure strategy

Answer 8

• Highly digestible ingredients
• Limit number of food ingredients
• Canned vs. dry foods
• Avoid protein excess
• Minimize food preservatives and coloring additives to simplify the diet: Canned foods, Therapeutic diets (novel protein, hydrolyzed protein), Balanced homemade elimination diets

Question 9

When doing an elimination trial, you need to feed the new diet only for _____ for dermatological dz and _____ for GI disease.

Answer 9

4-12 wks

2-4 wks

Question 10

Non-immunologically mediated food intolerance

Answer 10

• food poisoning: nutrient excess, contamination by microbe or its toxins, specific foods (grapes, onions), toxic preservatives
• reaction to food additives (controversial)
• reactions to vasoactive amines in food
• CHO intolerance (Adult hypolactasia)
• dietary indiscretion