Cytomegalovirus and the eye

Abstract

Following primary infection, cytomegalovirus (CMV) establishes latent infection in myeloid progenitor cells and intermittent viral reactivation from activated macrophages or dendritic cells, which is brought under control by strong virus-specific CD4 þ T-cell and CD8 þ T-cell responses. CMV retinitis characterized by spreading retinal necrosis due to viral cytopathic effect occurs in patients who have impaired T-cell function as a result of transplantation, AIDS, or immunosuppressive treatment. The diagnosis of CMV retinitis can be confirmed by PCR amplification of viral DNA in aqueous. When administered intravenously, the antiviral drugs Ganciclovir and Foscarnet have modest penetration into the vitreous compared with direct intra-vitreal injection. In randomized trials of HIV-associated CMV retinitis, a Ganciclovir implant was consistently superior to intravenous Ganciclovir in preventing progression of retinitis. CMV is also implicated in two forms of anterior segment disease in immuno-competent adults, namely CMV anterior uveitis and CMV corneal endotheliitis.

Cytomegalovirus and Eye

“…2,3 Therefore, studies such as the current one, which included only 425 patients in the shieldless group, 1 are not adequately powered to detect a significant difference in the rates of endophthalmitis. If even a single case of endophthalmitis had occurred in the shieldless group, the rate would have been 0.24%, which would certainly be a cause of concern, regardless of whether it was significantly higher compared with 0.10% in the shielded group.…”

“…1 However, these patients did not have a prior experience of not wearing an eye shield to compare with. In a prospective randomized controlled trial of 60 consecutive patients undergoing bilateral cataract surgery with one eye patched and the other without postoperative patching, Stifter et al 4 reported that within the first 4 hours of cataract surgery, pain scores were significantly higher in eyes who had no eye patches (mean score 1.7 vs 0.55, P o0.001), and postulated that this was related to the faster tear break up time in patients with no ocular protection (4.6 vs 7.1 s, Po0.001).…”

“…1 In addition to the clinical features reported by the author, 1 we would like to highlight some additional salient clinical points associated with CMV and eye.…”

Cytomegalovirus Retinitis in a Patient with Proliferative Diabetes Retinopathy

“…3 Especially, diabetes mellitus is a risk factor for bacterial or mycotic endophthalmitis, but it has not been associated with CMV retinitis. 4 We describe a case of CMV retinitis in an HIV-negative, CMV Ag-, IgM-, and IgG-negative patient with proliferative diabetic retinopathy (PDR) causing vitreous hemorrhage but no evidence of immunological dysfunction, and we consider diabetes mellitus as a risk factor for CMV infection.…”

“…Interestingly, it is possible that this patient had not been infected with CMV previously, because of the initial negative CMV IgM and CMV IgG findings and later seroconversion, although CMV retinitis usually occurs by reactivation of previous infection. 4 If multiplex PCR becomes more generally available and simpler to perform, more cases of primary or secondary CMV retinitis might be detected regardless of the visibility of the fundus. Nevertheless, ophthalmologists should be aware that if atypical features of PDR are observed, the multiplex PCR test using vitreous sample should be performed to investigate the real disease condition.…”