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We thank Drs Sandler and Rosenberg for their interest in our article and are grateful for their valuable comments on our treatment regimen.1Teoh S.C. Ou X. Lim T.H. Intravitreal ganciclovir maintenance injection for cytomegalovirus retinitis: efficacy of a low-volume, intermediate-dose regimen.Ophthalmology. 2012; 119: 588-595Abstract Full Text Full Text PDF PubMed Scopus (43) Google Scholar To clarify our analysis, we would like to reiterate that one of our primary outcome measures was the median time to progression. This was reported based on survival analysis, which is not the same as recurrence rates at fixed time points. In Cochereau-Massin's study, the relapse rate of 53% was reported for a period of 8 weeks.2Cochereau-Massin I. Lehoang P. Lautier-Frau M. et al.Efficacy and tolerance of intravitreal ganciclovir in cytomegalovirus retinitis in acquired immune deficiency syndrome.Ophthalmology. 1991; 98: 1348-1353Abstract Full Text PDF PubMed Scopus (179) Google Scholar The advantage of survival analysis is that it also takes into consideration the disease-free interval enjoyed by those who did not recur or progress. Using survival analysis also allowed us to analyze a pool of patients with variable follow-up periods. Although there was a large range of follow-up period in our retrospective analysis, about 87.5% patients had about ≥60 days of follow-up. As such, we feel that our analysis is valid. In our treatment protocol, we have adopted an induction and maintenance regimen similar to other authors,2Cochereau-Massin I. Lehoang P. Lautier-Frau M. et al.Efficacy and tolerance of intravitreal ganciclovir in cytomegalovirus retinitis in acquired immune deficiency syndrome.Ophthalmology. 1991; 98: 1348-1353Abstract Full Text PDF PubMed Scopus (179) Google Scholar, 3Cantrill H.L. Henry K. Melroe N.H. et al.Treatment of cytomegalovirus retinitis with intravitreal ganciclovir: long-term results.Ophthalmology. 1989; 96: 367-374Abstract Full Text PDF PubMed Scopus (178) Google Scholar with the main difference in our lower volume utilized and that we have 1 month of high-dose (2 mg), weekly maintenance followed by an intermediate maintenance dose of 1 mg weekly.1Teoh S.C. Ou X. Lim T.H. Intravitreal ganciclovir maintenance injection for cytomegalovirus retinitis: efficacy of a low-volume, intermediate-dose regimen.Ophthalmology. 2012; 119: 588-595Abstract Full Text Full Text PDF PubMed Scopus (43) Google Scholar The induction phase of 2 mg twice weekly is, however, only for 1 month (28 days) and not an 8-week course as misinterpreted by Sandler and Rosenberg. As such, in our study patients have a considerably longer maintenance period. Using just medians (which is oversimplifying the analysis), they would have had ≥67 days (39+28) days of maintenance therapy, which is ample time to document relapse and progression rates. Our results are thus comparable with both studies by Cochereau-Massin and Cantrill.2Cochereau-Massin I. Lehoang P. Lautier-Frau M. et al.Efficacy and tolerance of intravitreal ganciclovir in cytomegalovirus retinitis in acquired immune deficiency syndrome.Ophthalmology. 1991; 98: 1348-1353Abstract Full Text PDF PubMed Scopus (179) Google Scholar, 3Cantrill H.L. Henry K. Melroe N.H. et al.Treatment of cytomegalovirus retinitis with intravitreal ganciclovir: long-term results.Ophthalmology. 1989; 96: 367-374Abstract Full Text PDF PubMed Scopus (178) Google Scholar Our study is also applicable in the current day and age when highly active antiretroviral therapy (HAART) has become widely available and more affordable in many developing countries. Even when on HAART, treatment and control of cytomegalovirus (CMV) retinitis in patients with advanced AIDS must continue until the patient immune resconstitutes, which typically takes several months after commencing HAART.4Kigozi B.K. Sumba S. Mudyope P. et al.The effect of AIDS defining conditions on immunological recovery among patients initiating antiretroviral therapy at Joint Clinical Research Centre, Uganda.AIDS Res Ther. 2009; 6: 17Crossref PubMed Scopus (20) Google Scholar During this period, the patient has to be treated with anti-CMV therapy such as valganciclovir, which is both expensive and usually unavailable in these centers. Our intravitreal regimen is effective and provides and inexpensive treatment and control of CMV retinitis over this period while the patient immune reconstitutes on antiretroviral therapy. Ganciclovir for Cytomegalovirus RetinitisOphthalmologyVol. 119Issue 11PreviewThe study by Teoh et al1 describes their experience using an intermediate dose weekly injection of intravitreal ganciclovir for maintenance therapy in the treatment of cytomegalovirus retinitis in AIDS patients. This retrospective review of outpatients reported that 50% of patients remained stable on the intermediate dose maintenance regimen they used (1.0 mg/0.02 ml weekly intravitreal injection). Full-Text PDF