Late emergence of A594V and L595W mutations related to ganciclovir resistance in a patient with HCMV retinitis and long-term HIV progression

The emergence of ganciclovir (GCV) resistance during the treatment of human cytomegalovirus (HCMV) infection is a serious clinical challenge, and is associated with high morbidity and mortality. In this case report, we describe the emergence of two consecutive mutations (A594V and L595W) related to GCV resistance in a patient with HCMV retinitis and long-term HIV progression after approximately 240 days of GCV use. Following the diagnosis of retinitis, the introduction of GCV did not result in viral load reduction. The detected mutations appeared late in the treatment, and we propose that other factors (high initial HCMV load, previous GCV exposure, low CD4+ cell count), in addition to the presence of resistance mutations, may have contributed to the treatment failure of HCMV infection in this patient.

人类巨细胞病毒（HCMV）感染治疗期间出现更昔洛韦（GCV）耐药性，是一项严峻的临床挑战，且与较高的发病率和死亡率显著相关。本病例报告中，我们详细描述了1例伴有长期HIV感染进展的HCMV视网膜炎患者，在接受更昔洛韦治疗约240天后，出现了与GCV耐药相关的两处连续突变（A594V与L595W）。确诊视网膜炎后，初始予以更昔洛韦治疗并未实现病毒载量的降低。本次检出的突变于治疗后期才出现，我们推测，除耐药突变的存在外，其他因素（初始HCMV载量较高、既往更昔洛韦暴露史、CD4+细胞计数偏低）或共同促成了该患者HCMV感染的治疗失败。