title: Treatment outcomes of reduced-dose intravitreal ganciclovir for cytomegalovirus retinitis.
abstract: BACKGROUND
  Cytomegalovirus retinitis (CMVR) is one of the most common opportunistic infection in immunocompromised individuals. Intravitreal ganciclovir injection has been used successfully but no standard regimen was established. Risks of drug toxicity, endophthalmitis, and injection-related complications increased with number and frequency of injection. The aim of this study is to evaluate the outcomes of reduced-dose intravitreal ganciclovir (2 mg/0.04 mL) for the treatment of CMVR.
  
  
  METHODS
  A prospective observational cohort study involving 67 eyes of 49 patients with CMVR was performed. Induction therapy involved intravenous ganciclovir (10 mg/kg/day) for 2 weeks unless contraindicated or patients refused. Patients were then treated with reduced-dose intravitreal ganciclovir every week for 4 weeks, and then every other week until the lesion healed. The patients' demographic data were recorded, and vision parameters were examined every visit.
  
  
  RESULTS
  Twenty eyes (29.9 %) presented with initial visual acuities less than 6/60. The majority of patients were diagnosed with CMVR in zones 1 or 2 (63 eyes, 94 %), and, at least, one quadrant of the retina was involved (56 eyes, 83.6 %). Forty-one eyes (61.2 %) completely resolved after treatment within the 6-month follow-up. There was no significant difference in healing time, whether or not patients received induction treatment with intravenous ganciclovir (111.00 ± 12.96 vs 105.00 ± 28.32 days, p = 0.8). Five eyes (12.2 %) of patients with healed CMVR had visual acuities less than 6/60.
  
  
  CONCLUSIONS
  Reduced-dose intravitreal ganciclovir is a safe and effective treatment option. It provides comparable results to other weekly regimens. Induction with intravenous ganciclovir is not crucial in a resolution of retinitis, although it may be necessary to reduce systemic cytomegalovirus loads and mortality rates.
  
  
  BACKGROUND
  The trial was registered with Thai Clinical Trials Registry (TCTR) on 16 March 2016 - TCTR20160316001 .
authors.affiliation: Department of Ophthalmology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand. pitipol.cho@mahidol.edu.
authors.forename: Pitipol
authors.initials: P
authors.lastname: Choopong
authors.affiliation: Department of Ophthalmology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
authors.forename: Kamolporn
authors.initials: K
authors.lastname: Vivittaworn
authors.affiliation: Department of Ophthalmology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
authors.forename: Duanphen
authors.initials: D
authors.lastname: Konlakij
authors.affiliation: Department of Ophthalmology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
authors.forename: Somanus
authors.initials: S
authors.lastname: Thoongsuwan
authors.affiliation: Department of Ophthalmology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
authors.forename: Auengporn
authors.initials: A
authors.lastname: Pituksung
authors.affiliation: Department of Ophthalmology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
authors.forename: Nattaporn
authors.initials: N
authors.lastname: Tesavibul
mesh_terms: D061605:Administration, Intravenous; D000328:Adult; D000998:Antiviral Agents / Q000008:administration & dosage*; D015331:Cohort Studies; D003587:Cytomegalovirus / Q000472:pathogenicity; D017726:Cytomegalovirus Retinitis / Q000188:drug therapy* / Q000473:pathology / Q000821:virology; D003710:Demography; D005260:Female; D015774:Ganciclovir / Q000008:administration & dosage*; D006801:Humans; D016867:Immunocompromised Host; D058449:Intravitreal Injections; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D016896:Treatment Outcome; D014792:Visual Acuity
chemical_list: D000998:Antiviral Agents; D015774:Ganciclovir
keywords: Cytomegalovirus retinitis; Ganciclovir; Intravitreal injections; Treatment outcomes