Infectious diseases: cytomegalovirus retinitis: practice question

A General Medicine 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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General Medicine · Infectious diseases: cytomegalovirus retinitis

Sample item

A man with untreated HIV and a CD4 count of 25 cells per microlitre has painless progressive loss of vision in one eye. Fundoscopy shows yellowish-white retinal necrosis with haemorrhages along the vessels. What is the most appropriate treatment?

AAciclovirBPyrimethamine with sulfadiazineCAmphotericin BDGanciclovir with antiretroviral therapy

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

The answer and the reasoning

D. Ganciclovir with antiretroviral therapy

CMV retinitis is the commonest opportunistic eye infection in AIDS, typically at CD4 below 50 cells per microlitre, producing a granular necrotising retinitis with haemorrhages. Treatment is intravenous ganciclovir (or oral valganciclovir) with intravitreal therapy as needed, and antiretroviral therapy to restore immunity. Foscarnet is used for resistance.

Option by option

A. Aciclovir
Aciclovir has insufficient activity against CMV because CMV lacks the thymidine kinase activation step.
B. Pyrimethamine with sulfadiazine
Pyrimethamine with sulfadiazine treats toxoplasma chorioretinitis, which is a focal necrotic lesion with vitritis.
C. Amphotericin B
Amphotericin B treats fungal infection and not CMV.
D. Ganciclovir with antiretroviral therapy (correct)
Ganciclovir inhibits CMV DNA polymerase and is the first-line agent.

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.

Questions about this General Medicine question

What is the answer to this General Medicine question?

The best answer is D, Ganciclovir with antiretroviral therapy. CMV retinitis is the commonest opportunistic eye infection in AIDS, typically at CD4 below 50 cells per microlitre, producing a granular necrotising retinitis with haemorrhages.

Why is "Aciclovir" not the answer?

Aciclovir has insufficient activity against CMV because CMV lacks the thymidine kinase activation step.

Why is "Pyrimethamine with sulfadiazine" not the answer?

Pyrimethamine with sulfadiazine treats toxoplasma chorioretinitis, which is a focal necrotic lesion with vitritis.

Why is "Amphotericin B" not the answer?

Amphotericin B treats fungal infection and not CMV.

What concept does this question test?

It tests Infectious diseases: cytomegalovirus retinitis in General Medicine. Treatment is intravenous ganciclovir (or oral valganciclovir) with intravitreal therapy as needed, and antiretroviral therapy to restore immunity. Foscarnet is used for resistance.

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 Infectious diseases: cytomegalovirus retinitis?

For each disease know the classic presentation, the best test, and the first-line treatment. Then use the flashcards and the other General Medicine 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.