Question
A patient presents with a localized allergic skin reaction consistent with shown below. Based on the distribution and morphology, which of the following is the most likely chemical allergen responsible for this reaction?
| A. |
Pollen
|
| B. |
PPD
|
| C. |
Balsum of peru
|
| D. |
Hexa
|
Show Answer
|
Correct Answer » B
Explanation
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|
The given image shows Allergic Contact Dermatitis (ACD):
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ACD is a Type IV hypersensitivity reaction caused by direct skin contact with allergens.
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It presents with erythema, vesicles, itching, and scaling at the site of exposure.
PPD (Para-phenylenediamine):
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Commonly found in hair dyes, temporary black henna tattoos, and leather dyes.
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Causes severe allergic contact dermatitis, especially on the scalp, neck, and face.
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Symptoms appear 48–72 hours after exposure.
