Communicable diseases: ascariasis life cycle: practice question

A PSM 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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PSM · Communicable diseases: ascariasis life cycle

Sample item

A 6-year-old child in a slum has had a dry cough, wheeze, fleeting chest infiltrates and eosinophilia for a week. Two weeks later the mother brings a long, pink, cylindrical worm passed in the stool. Which parasite is responsible?

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

The answer and the reasoning

B. Ascaris lumbricoides

Ascaris eggs are swallowed from contaminated soil, larvae penetrate the gut, travel through the liver to the lungs, and are coughed up and swallowed to mature in the small intestine. The pulmonary phase explains the transient infiltrates and eosinophilia, known as Loeffler syndrome.

Option by option

  • A. Trichuris trichiura

    Trichuris is a whip-shaped worm and its larvae do not migrate through the lungs.

  • B. Ascaris lumbricoides (correct)

    Correct. The pulmonary larval migration followed by a passed long roundworm is typical of Ascaris.

  • C. Enterobius vermicularis

    Enterobius is a small worm causing perianal itching and has no lung migration.

  • D. Taenia solium

    Taenia solium is a tapeworm passed as flat proglottids and has no pulmonary phase.

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 PSM questions

Questions about this PSM question

What is the answer to this PSM question?

The best answer is B, Ascaris lumbricoides. Ascaris eggs are swallowed from contaminated soil, larvae penetrate the gut, travel through the liver to the lungs, and are coughed up and swallowed to mature in the small intestine.

Why is "Trichuris trichiura" not the answer?

Trichuris is a whip-shaped worm and its larvae do not migrate through the lungs.

Why is "Enterobius vermicularis" not the answer?

Enterobius is a small worm causing perianal itching and has no lung migration.

Why is "Taenia solium" not the answer?

Taenia solium is a tapeworm passed as flat proglottids and has no pulmonary phase.

What concept does this question test?

It tests Communicable diseases: ascariasis life cycle in PSM. The pulmonary phase explains the transient infiltrates and eosinophilia, known as Loeffler syndrome.

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 Communicable diseases: ascariasis life cycle?

Practise biostatistics with small calculations until sensitivity, predictive values and risk measures are automatic. Then use the flashcards and the other PSM 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.