Virology USMLE Step 1 Practice Question
A 55-year-old man with HIV infection has been on antiretroviral therapy for 3 years with a CD4+ count of 487 cells/Ī¼L and undetectable viral load until 6 months ago. He now presents for follow-up, and repeat testing shows an HIV RNA level of 1,240 copies/mL. Genotypic resistance testing reveals mutations in the HIV pol gene conferring reduced susceptibility to darunavir and ritonavir. The patient's current regimen includes these two agents plus tenofovir and emtricitabine. Which of the following viral processes is most directly impaired by the mechanism of action of the drugs to which resistance has developed?
Answer choices
- AReverse transcription of viral RNA into DNA
- BIntegration of viral DNA into the host chromosome
- CProteolytic cleavage of viral polyproteins into functional enzymesCorrect answer
- DBinding of viral envelope glycoproteins to CD4 and coreceptors
- FFusion of viral and host cell membranes
- ENuclear export of newly synthesized viral RNA
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