Virology: cytomegalovirus retinitis: 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 · Virology: cytomegalovirus retinitis

Sample item

A man with AIDS and a CD4 count of 30 cells/mm3 has progressive floaters and loss of vision. Fundoscopy shows perivascular yellow-white infiltrates with haemorrhages. He is started on intravenous ganciclovir. Which adverse effect needs monitoring?

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

The answer and the reasoning

C. Neutropenia

Cytomegalovirus retinitis occurs in advanced HIV and is treated with ganciclovir, which is phosphorylated by the viral UL97 kinase and inhibits viral DNA polymerase. Its main toxicity is bone marrow suppression, especially neutropenia, so blood counts are monitored. Foscarnet in contrast causes renal toxicity.

Option by option

  • A. Crystalluria

    Crystalluria is associated with intravenous acyclovir.

  • B. Pancreatitis

    Pancreatitis is associated with didanosine.

  • C. Neutropenia (correct)

    Correct. Bone marrow suppression, especially neutropenia, is the main toxicity of ganciclovir.

  • D. Nephrotoxicity with electrolyte wasting

    Nephrotoxicity with electrolyte disturbances is characteristic of foscarnet.

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, Neutropenia. Cytomegalovirus retinitis occurs in advanced HIV and is treated with ganciclovir, which is phosphorylated by the viral UL97 kinase and inhibits viral DNA polymerase.

Why is "Crystalluria" not the answer?

Crystalluria is associated with intravenous acyclovir.

Why is "Pancreatitis" not the answer?

Pancreatitis is associated with didanosine.

Why is "Nephrotoxicity with electrolyte wasting" not the answer?

Nephrotoxicity with electrolyte disturbances is characteristic of foscarnet.

What concept does this question test?

It tests Virology: cytomegalovirus retinitis in Microbiology. Its main toxicity is bone marrow suppression, especially neutropenia, so blood counts are monitored. Foscarnet in contrast causes renal toxicity.

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 Virology: cytomegalovirus retinitis?

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.