Bacteriology: Listeria meningitis therapy: practice question

A Microbiology 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

Microbiology · Bacteriology: Listeria meningitis therapy

Sample item

A 72-year-old renal transplant recipient on tacrolimus has fever, neck stiffness and confusion. CSF Gram stain shows Gram-positive bacilli. He has been started on ceftriaxone and vancomycin. Which addition is most appropriate?

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

The answer and the reasoning

C. Ampicillin

Listeria monocytogenes meningitis in immunosuppressed and elderly patients is treated with ampicillin, often with gentamicin. Listeria is intrinsically resistant to cephalosporins, so the usual empirical cephalosporin cover is inadequate.

Option by option

  • A. Cefepime

    Cefepime is a cephalosporin and lacks reliable activity against Listeria.

  • B. Ceftazidime

    Ceftazidime is a cephalosporin and is ineffective against Listeria.

  • C. Ampicillin (correct)

    Correct. Ampicillin is the drug of choice for Listeria, which resists cephalosporins.

  • D. Aztreonam

    Aztreonam has no useful activity against Gram-positive organisms.

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 Microbiology questions

Questions about this Microbiology question

What is the answer to this Microbiology question?

The best answer is C, Ampicillin. Listeria monocytogenes meningitis in immunosuppressed and elderly patients is treated with ampicillin, often with gentamicin.

Why is "Cefepime" not the answer?

Cefepime is a cephalosporin and lacks reliable activity against Listeria.

Why is "Ceftazidime" not the answer?

Ceftazidime is a cephalosporin and is ineffective against Listeria.

Why is "Aztreonam" not the answer?

Aztreonam has no useful activity against Gram-positive organisms.

What concept does this question test?

It tests Bacteriology: Listeria meningitis therapy in Microbiology. Listeria is intrinsically resistant to cephalosporins, so the usual empirical cephalosporin cover is inadequate.

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 Bacteriology: Listeria meningitis therapy?

Make a one-line identity card for each organism: shape and stain, defining test, toxin, disease and drug. Then use the flashcards and the other Microbiology 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.