Development of cytomegalovirus retinitis after negative conversion of cytomegalovirus antigenemia due to systemic antiviral therapy.

Purpose: Cytomegalovirus (CMV) antigenemia assays have been widely used as adjunct tests to diagnose tissue invasive CMV diseases, including cytomegalovirus retinitis (CMVR). In this study, we examined CMVR cases to assess the presence of CMV in sera and aqueous humor and antiviral therapy received prior to the onset of CMVR.

Methods: A total of 37 eyes from 26 different cases of CMVR in patients who visited Hokkaido University Hospital between 2007 and 2015 were enrolled. The diagnosis of CMVR was established based on characteristic ophthalmoscopic findings and the presence of local and/or systemic CMV infection. Among the 26 cases, 3 cases (12%) were HIV-positive, while the other 23 cases (88%) were HIV-negative. The records of clinical and laboratory results were reviewed from clinical charts retrospectively.

Results: CMV antigenemia was positive at the onset of CMVR in 14 cases (53.8%) and negative in the other 12 cases. In 9 cases among the antigenemia-negative cases (75.0%), the antigenemia had been previously positive and had turned negative before the onset of CMVR. In 12 of the 14 antigenemia-positive cases (85.7%) and in 8 of the 9 antigenemia-negative cases (88.9%) that were previously positive, systemic antiviral therapies had never been used or had been used before but had been discontinued prior to the onset of CMVR.

Conclusion: Even if viremia turns negative, the risk of developing CMVR exists for more than several weeks after the completion of systemic therapy.