Comparison of Cytomegalovirus UL97 Gene Sequences in the Blood and Vitreous of Patients with AIDS and Cytomegalovirus Retinitis

Abstract

Abstract: : Purpose:Cytomegalovirus (CMV) resistance to ganciclovir occurs either via mutations in the UL97 gene or via mutations in both the UL97 and UL54 genes (high-level resistance). Methods:Cytomegalovirus UL97 DNA from vitreous and blood specimens and from culture isolares from 87 patients with AIDS and CMV retinitis who received a ganciclovir implant was sequenced to identify the relationship between the CMV UL97 gene sequences in the eye and in the the peripheral blood. Results:There was 98% agreement between blood and vitreous for detection of the UL97 gene sequence in the vitreous (kappa = 0.90). Sequence analysis of vitreous specimens showed that 15% of the patients (13/87) had either a ganciclovir resistance-conferring mutation or a polymorphism in the CMV UL97 gene. Eleven of 13 mutations or polymorphisms in the vitreous were identified in blood; in one patient the vitreous and blood were different, and in one patient the comparison was uninformative due to negative blood PCR and culture. Conclusion:Although the limited number of mutations limits definitive interpretation, these data suggest that blood specimens may reflect the events occurring in the eyes of patients with CMV retinitis.

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