Vesiculobullous disorders: HLA association in dermatitis herpetiformis: practice question

A Dermatology question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

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Dermatology · Vesiculobullous disorders: HLA association in dermatitis herpetiformis

Sample item

A 30-year-old has intensely itchy grouped vesicles and excoriations over the elbows, knees and buttocks. Biopsy of perilesional skin shows granular IgA deposits at the tips of the dermal papillae. Which HLA haplotype is carried by most such patients?

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

A. HLA-DQ2 or HLA-DQ8

Dermatitis herpetiformis is the cutaneous form of gluten sensitivity, and almost all patients carry HLA-DQ2 or DQ8, as in coeliac disease. IgA against epidermal transglutaminase deposits in the papillary dermis. Dapsone controls itch, and a gluten-free diet treats the underlying enteropathy.

Option by option

  • A. HLA-DQ2 or HLA-DQ8 (correct)

    Correct. HLA-DQ2 or DQ8 is shared with coeliac disease and almost universal in dermatitis herpetiformis.

  • B. HLA-B27

    HLA-B27 is linked to ankylosing spondylitis and reactive arthritis.

  • C. HLA-B*15:02

    HLA-B*15:02 predicts carbamazepine-induced Stevens-Johnson syndrome in some Asian populations.

  • D. HLA-Cw6

    HLA-Cw6 is associated with early-onset plaque psoriasis.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

More Dermatology questions

Questions about this Dermatology question

What is the answer to this Dermatology question?

The best answer is A, HLA-DQ2 or HLA-DQ8. Dermatitis herpetiformis is the cutaneous form of gluten sensitivity, and almost all patients carry HLA-DQ2 or DQ8, as in coeliac disease.

Why is "HLA-B27" not the answer?

HLA-B27 is linked to ankylosing spondylitis and reactive arthritis.

Why is "HLA-B*15:02" not the answer?

HLA-B*15:02 predicts carbamazepine-induced Stevens-Johnson syndrome in some Asian populations.

Why is "HLA-Cw6" not the answer?

HLA-Cw6 is associated with early-onset plaque psoriasis.

What concept does this question test?

It tests Vesiculobullous disorders: HLA association in dermatitis herpetiformis in Dermatology. IgA against epidermal transglutaminase deposits in the papillary dermis. Dapsone controls itch, and a gluten-free diet treats the underlying enteropathy.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Vesiculobullous disorders: HLA association in dermatitis herpetiformis?

Learn each condition by its primary lesion, site and signature sign. Then use the flashcards and the other Dermatology questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.