Cytomegalovirus infections retinitis

Antiviral drugp interfere with viral reproduction by altering DNA synthesis. These drug are used in the treatment of herpes simplex infections of the eye, treatment in immunocompromised patients with cytomegalovirus (CMV) retinitis, and for the prevention of CMV retinitis in patients undergoing transplant. 

Valganciclovir Valcyte Treatment of cytomegalovirus (CMV] retinitis in immunocompromised patients also used to prevent CMV infection after organ transplants... 

Foscamet is used for the treatment of cytomegalovirus (CMV) retinitis and mucocutaneous acyclovir-resistant herpes simplex virus (HSV) infections. It may also be beneficial in other types of CMV or HSV infections (Wagstaff and Bryson, 1994). 

Infliximab can compromise antiviral defence mechanisms. There have been detailed reports of cytomegalovirus retinitis (53) and life-threatening disseminated cytomegalovirus infection (54). Most of these patients were taking concomitant immunosuppressants at the time of diagnosis. 

Surveillance data indicate that the incidence of certain OIs in HIV-infected persons in the United States continues to change. The three major OIs—Pneumocystis carinii pneumonia (PCP), Mycobacterium avium complex (MAC) disease, and cytomegalovirus (CMV) retinitis—all have decreased in incidence. Potent antiretroviral reg-... 

Gross JG, Sadun AA, Wiley CA, Freeman WR. Severe visual loss related to isolated peripapillary retinal and optic nerve cytomegalovirus infection. Am J Ophthalmol 1989 108 691. 

Smith IL, Macdonald JC, Freeman WR, Shapiro AM, Spector SA. Cytomegalovirus (CMV) retinitis activity is accurately reflected by the presence and level of CMV DNA in aqueous humor and vitreous. J Infect Dis 1999 179 1249-1253. 

The first antisense therapeutic agent to reach the market is fomivirsen (ISIS 2922) (19). Fomivirsen is a 21-mer phosphorothioate oligodeoxynucleotide (Fig. 8.5). It inhibits human cytomegalovirus (CMV), a ubiquitous herpesvirus that is the most common cause of viral retinitis in immunocompromised patients, especially those with FIIV infection. Cytomegalovirus infection is characterized by the progressive destruction of retinal cells and, if untreated, leads to retinal detachment and blindness. Even with treatment, some degree of visual loss occurs in nearly all patients with a diagnosis of CMV retinitis. It can affect one or both eyes. 

Cytomegalovirus (CMV) is a herpesvirus, which causes an inapparent infection in immunocompetent persons. Worldwide, approximately 40% of people are infected with CMV. In immunocompromised patients, transplant recipients and neonates, CMV can cause serious and potentially lethal disease manifestations like pneumonia, retinitis and blindness, hepatitis, infections of the digestive tract, deafness or mental retardation. 

Jabs DA (1995) Ocular manifestations of HIV infection. Trans Am Ophthalmol Soc 93 623-683 Jabs DA, Enger C, Dunn JP, Forman M (1998a) Cytomegalovirus retinitis and viral resistance ganciclovir resistance. J Infect Dis 177 770-773... 

Momma, Y, Nagineni, CN, Chin, MS, Srinivasan, K, Detrick, B, and Hooks, JJ, 2003. Differential expression of chemokines by human retinal pigment epithelial cells infected with cytomegalovirus. Invest Ophthalmol... 

Wolf DL, Rodriguez CA, Mucci M, et al. Pharmacokinetics and renal effects of cidofovir with a reduced dose of probenecid in HIV-infected patients with cytomegalovirus retinitis. J Clin Pharmacol. 2003 43 43-51. 

The Vitrasert implant has been developed to deliver therapeutic levels of ganciclovir locally to the eye, for the treatment of retinitis infected by Cytomegalovirus (CMV) (see Section 12.4.2). Localized delivery to the eye minimizes the systemic side effects of the drug. The implant is surgically placed in the vitreous cavity of the eye and delivers therapeutic levels of ganciclovir for up to 32 weeks. 

The lack of effect of available nucleoside analogs on cytomegalovirus (CMV) infection led to the synthesis of the acyclovir analog, ganciclovir [gan SYE kloe ver] (9-[(1,3-dihydroxy-2-propoxy)methyl]guanine, DHPG). It is currently available for treatment of cytomegalic retinitis in immunocompromised patients. 

Herpesviruses range in size from 120 to 300 nm and have DNA genomes and outer lipid membranes (envelopes). As enveloped viruses, herpesviruses are sensitive to drying and adverse conditions. Herpesviruses are spread by inoculation of susceptible mucous membranes or direct cell-to-cell contact. Over 100 herpesviruses have been identified, but only 5 cause human eye infections with any frequency herpes simplex virus-1 (HSV-1), herpes simplex virus-2 (HSV-2), varicella zoster virus (VZV), cytomegalovirus (CMV), and Epstein-Barr virus. Herpesviruses can cause blepharitis, conjunctivitis, epithelial and stromal keratitis, uveitis, retinitis, and ARN. HSV-1 is the most frequent cause of primary and recurrent eye disease. The host immime system influences the rates of reactivation. Immimocompromised patients tend to have more frequent reactivations and more severe disease manifestations. The strain of virus also affects the... 

Acquired immunodeficiency renders a host much more susceptible to secondary infections, including cytomegalovirus, syphilis, herpes zoster, fungi, hepatitis B, tuberculosis, and toxoplasmosis. HIV invades the tissues of the optic nerve and initiates an immune complex-mediated response that results in an optic neittopathy. The primary HIV infection may be responsible for color vision defects, loss of contrast sensitivity, and visual field defects. HIV infection itself may also cause direct degeneration of retinal ganglion cell axons in the optic nerve without a secondary opportunistic infection. 

Figure 31-2 Acute retinal necrosis syndrome, with confluent retinal whitening, vitreitis, and vasculitis. (Reprinted with permission from Holland GN, Tufail A, Jordan MC. Cytomegalovirus diseases. In Pepose JS, Holland GN, WUheknus KR, ed. Ocular infection and immunity. St. Louis, MO Mosby, 1996.)...

Berenguer J, Mallolas J, Padilla B, Colmenero M, Santos I. Intravenous cidofovir for compassionate use in AIDS patients with cytomegalovirus retinitis. Spanish Cidofovir Study Group. Clin Infect Dis 2000 30(l) 182-4. 

Jacobson MA, Drew WL, Feinberg J, O Donnell JJ, Whitmore PV, Miner RD, Parenti D. Foscamet therapy for ganciclovir-resistant cytomegalovirus retinitis in patients with AIDS. J Infect Dis I99I I63(6) I348-5I. 

Retinitis—Inflammation of the retina, often due to infection with cytomegalovirus. 

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