Chapter 24 :: Allergic Contact Dermatitis

Question 1

Allergic contact dermatitis (ACD)

Answer 1

s a cell-mediated (type IV), delayed type, hypersensitivity reaction

Question 2

most prevalent contact allergens in the general populations

Answer 2

nickel

Question 3

Pigmented ACD

Answer 3

Riehl melanosis

Question 4

one of the most potent sensitizers known and is widely used as an ingredient in hair dyes

Answer 4

para-phenylenediamine (PPD)

Question 5

nail lacquer

Answer 5

tosylamide formaldehyde resin

Question 6

major constituent of many sunscreens, is also a common ingredient in many lip products

Answer 6

Benzophenone-3 (oxybenzone)

Question 7

most common class of allergens to cause ACD of the feet are rubber-related chemicals

Answer 7

mercaptobenzothiazole

Question 8

potential cross-reactors with balsam of Peru

Answer 8

Tomatoes, citrus peel/zest, chocolate, ice cream, wine, beer, dark-colored sodas, and spices such as cinnamon, cloves, curry, and vanilla

Question 9

testing to liquid products with irritant potential

Answer 9

semiopen patch test

Question 10

represents a weak nonvesicular reaction but with palpable erythema

Answer 10

+

Question 11

represents a strong (edematous or vesicular) reaction

Answer 11

++

Question 12

represents an extreme (bullous or ulcerative) reaction

Answer 12

+++

Question 13

erythematous reactions limited to the site of application of the chemical, with sharp, well-delineated margins; discretely scaly (may look “chapped”) and usually not edematous

Answer 13

irritant patch test reaction