Cell injury and adaptation: metachromatic leukodystrophy: practice question

A Pathology 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

Pathology · Cell injury and adaptation: metachromatic leukodystrophy

Sample item

A toddler regresses in gait and speech, and nerve biopsy shows metachromatic granules in myelin-forming cells. Which enzyme is deficient?

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

The answer and the reasoning

A. Arylsulfatase A

Metachromatic leukodystrophy results from arylsulfatase A deficiency, causing sulfatide accumulation in central and peripheral myelin and demyelination. Krabbe disease is the neighbouring disorder with galactocerebrosidase deficiency.

Option by option

  • A. Arylsulfatase A (correct)

    Correct. Arylsulfatase A deficiency causes sulfatide accumulation.

  • B. Sphingomyelinase

    Sphingomyelinase deficiency causes Niemann-Pick disease.

  • C. Galactocerebrosidase

    Galactocerebrosidase deficiency causes Krabbe disease with globoid cells.

  • D. Hexosaminidase A

    Hexosaminidase A deficiency causes Tay-Sachs disease with GM2 accumulation.

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 Pathology questions

Questions about this Pathology question

What is the answer to this Pathology question?

The best answer is A, Arylsulfatase A. Metachromatic leukodystrophy results from arylsulfatase A deficiency, causing sulfatide accumulation in central and peripheral myelin and demyelination.

Why is "Sphingomyelinase" not the answer?

Sphingomyelinase deficiency causes Niemann-Pick disease.

Why is "Galactocerebrosidase" not the answer?

Galactocerebrosidase deficiency causes Krabbe disease with globoid cells.

Why is "Hexosaminidase A" not the answer?

Hexosaminidase A deficiency causes Tay-Sachs disease with GM2 accumulation.

What concept does this question test?

It tests Cell injury and adaptation: metachromatic leukodystrophy in Pathology. Krabbe disease is the neighbouring disorder with galactocerebrosidase deficiency.

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 Cell injury and adaptation: metachromatic leukodystrophy?

Learn each disease as a bundle: cause, key histology, markers, and the clinical hallmark. Then use the flashcards and the other Pathology 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.