Leprosy: ENL histology: 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.

Try it

Dermatology · Leprosy: ENL histology

Sample item

A skin biopsy from a tender erythematous nodule in a patient with lepromatous leprosy shows a dense neutrophilic infiltrate with vasculitis and fragmented bacilli in foamy macrophages. What is the reaction?

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

The answer and the reasoning

B. Erythema nodosum leprosum

ENL shows neutrophils in a background of lepromatous foam cells, often with small vessel vasculitis and fragmented bacilli. Reversal reaction shows oedema and increased epithelioid granulomas with lymphocytes. Lucio phenomenon shows a necrotising vasculitis with abundant bacilli in endothelium.

Option by option

  • A. Lucio phenomenon with epidermal necrosis only

    Lucio phenomenon is a necrotising vasculitis in diffuse lepromatous leprosy with bacilli in vessel walls.

  • B. Erythema nodosum leprosum (correct)

    Correct. Neutrophils in lepromatous tissue define ENL.

  • C. Type 1 reversal reaction

    Reversal reaction has lymphocytic granulomas and oedema, not neutrophils.

  • D. Tuberculoid granuloma

    A tuberculoid granuloma is epithelioid with few bacilli, not neutrophilic.

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 B, Erythema nodosum leprosum. ENL shows neutrophils in a background of lepromatous foam cells, often with small vessel vasculitis and fragmented bacilli.

Why is "Lucio phenomenon with epidermal necrosis only" not the answer?

Lucio phenomenon is a necrotising vasculitis in diffuse lepromatous leprosy with bacilli in vessel walls.

Why is "Type 1 reversal reaction" not the answer?

Reversal reaction has lymphocytic granulomas and oedema, not neutrophils.

Why is "Tuberculoid granuloma" not the answer?

A tuberculoid granuloma is epithelioid with few bacilli, not neutrophilic.

What concept does this question test?

It tests Leprosy: ENL histology in Dermatology. Reversal reaction shows oedema and increased epithelioid granulomas with lymphocytes. Lucio phenomenon shows a necrotising vasculitis with abundant bacilli in endothelium.

How hard is this question?

We tag it as a multi-step question: it asks you to combine more than one idea. 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 Leprosy: ENL histology?

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.