A 45-year-old kidney transplant recipient on tacrolimus and mycophenolate presents with fever (38.9°C), malaise, and floaters with hemorrhagic retinitis on fundoscopy. Labs show leukopenia (WBC 2.8) and positive CMV PCR (8,200 copies/mL). He initially improves on ganciclovir but develops recurrent symptoms after 6 weeks with rising viral load (15,000 copies/mL) despite documented adherence. No opportunistic infections noted. Which viral enzyme mutation most commonly explains ganciclovir resistance?
- A)Thymidine kinase
- B)DNA dependent RNA polymerase
- C)Reverse transcriptase
- D)UL97 phosphotransferaseGABARITO
- E)Neuraminidase
Explicação
Ganciclovir requires phosphorylation by the cytomegalovirus UL97 phosphotransferase to become active. Mutations in UL97 are a common mechanism of CMV resistance in transplant recipients receiving prolonged therapy. Ver explicação completa e trilha adaptativa →