Acute necrotizing retinitis in a patient receiving immunosuppressive therapy

[Herpes and retinal lesions: what's new?]

The viral retinitis are linked to infection by herpes simplex virus (HSV), varicella zoster virus (VZV), cytomegalovirus (CMV). When the diagnosis is clinically suspected the antiviral treatment has to be introduced immediately after performing the ocular sampling to try to identify the infectious agent. Despite the various antiherpetic drugs available by intravenous routes and intravitreal injection, the prognostic of the herpetic retinitis remained severe because of the occurrence of retinal detachment, optic neuritis, macular necrosis. Various clinical forms are described: (1) the classical "acute necrotizing retinitis" (2) a form with a slow progression of the necrotizing retinitis (3) occlusive retinal arteritis (4) the highly severe "progressive retinal necrosis". The incidence of the CMV retinitis diminished with the highly antiretroviral therapy; however uveitis may occur with no active CMV retinitis. The various antiherpetic drugs are described with special indications.

Transient vitreous inflammatory reactions associated with combination antiretroviral therapy in patients with AIDS and cytomegalovirus retinitis

PURPOSE

To report the observation that a transient vitreous inflammatory reaction may develop in the eyes of patients with acquired immunodeficiency syndrome (AIDS), cytomegalovirus retinitis, and an increased CD4+ T-lymphocyte count during treatment with antiretroviral therapy including a protease inhibitor.

METHODS

We reviewed the medical records of eight patients with AIDS and cytomegalovirus retinitis who developed vitreous inflammatory reactions greater than those usually seen with this disease.

RESULTS

Vitreous inflammatory reactions obscured the view of the posterior pole in all patients. No iris nodules, synechiae, glaucoma, or cystoid macular edema were observed. Six patients had unilateral cytomegalovirus retinitis, and, in each, the inflammation occurred only in the eye with cytomegalovirus retinitis. The vitreous inflammatory reactions were associated with clinically inactive cytomegalovirus retinitis in six patients, with disease reactivation in one patient, and were present at diagnosis of active disease in one patient. Cytomegalovirus retinitis has not recurred in any of these patients since their episodes of vitreous inflammation. Vitreous inflammation developed in all eight patients after a substantial increase in CD4+ T-lymphocyte counts caused by combination antiretroviral therapy. Five patients had CD4+ T-lymphocyte counts of greater than 100 cells per microl at the time the vitreous inflammatory reaction developed. No other causes of uveitis were found.

CONCLUSIONS

Patients with AIDS and cytomegalovirus retinitis may develop transient intraocular inflammation associated with combination antiretroviral therapy. We believe that this inflammation reflects an improved immune response against cytomegalovirus.

Differential sensitivity of cultured retinal neurons and photoreceptors to herpes simplex infection

Infection of the retina with herpes simplex virus type 1 (HSV-1) causes devastating lesions usually leading to blindness. However, the interactions between individual retinal cell types and this virus have not been well characterized, probably because of limitations posed by the complexity of the intact retina. We have now approached this problem through the use of separate, purified populations of isolated chick embryo retinal neurons and photoreceptor cells, of glial cells, and of pigmented epithelial cells. This manuscript deals with the initial part of these studies, aimed at determining the susceptibility of different retinal types to HSV-1 infection. The different cultures were exposed to HSV-1 for 3-48 hr, and cell infection was evaluated by immunocytochemical detection of viral antigens or by autoradiographic study of viral DNA replication. Practically 100% of the retinal glial cells and pigmented epithelial cells appeared susceptible to HSV-1 infection. On the other hand, as many as 70% of the neurons present in glia-free, pigment epithelium-free cultures, also appeared infected after a 24-hr exposure to the virus. Neuronal susceptibility to HSV-1 was already present in early (2-day) cultures, was time- and concentration-dependent, and led to neuronal degeneration after 24-48 hr. Neuronal infection was also corroborated by the detection of viral particles by transmission electron microscopy. Photoreceptor cells were consistently and selectively resistant to HSV-1 infection at all the concentrations and time points investigated. Both immunocytochemical and autoradiographic studies showed similar results. Photoreceptor resistance to HSV-1 appears to be selective, since they could be readily infected with RNA viruses such as vesicular stomatitis virus and influenza virus. These cell culture preparations offer an attractive system for the investigation of cellular mechanisms involved in the differential susceptibility of retinal cells to viral infection. Moreover, they could also help in the screening of treatments potentially capable of preventing and (or) curing HSV-induced retinal infection.

Treatment and visual prognosis in Behçet's disease

For the last decade we have observed and regularly followed 49 patients with the ocular type of Behçet's disease. Thirty-six patients were males and 13 were females. Regardless of whether the initial ocular presenting symptoms were in the anterior or posterior segment, both segments were involved within two years. Sterile hypopyon was recorded in 17 out of the 49 patients during the process of follow-up. In three of the patients hypopyon was the presenting symptom. Characteristically there was a lack of corneal or scleral involvement in the disease process. All patients responded initially to treatment with steroids, but 42 had a course of treatment with cytotoxic-immunosuppressive drugs for various lengths of time after 'resistance' to steroids developed. Although definitely effective in reducing the intensity of the ocular inflammatory processes, it is not clear yet whether these modes of treatment have any dramatic effect of the visual prognosis of the affected eyes. Despite intensive follow-up and treatment, loss of useful visual acuity has occurred in 74% of the eyes six to 10 years after the start of the ocular symptoms.

The acute retinal necrosis syndrome. Possible herpes simplex retinitis

The acute retinal necrosis (ARN) syndrome is a severe necrotic peripheral retinitis with vasculitis and vitritis. It attacks healthy people and carries a poor visual prognosis. Five patients with ARN were seen. Two showed interesting clinical features. One patient developed the ARN syndrome in both eyes but with a 14-year hiatus separating the two episodes, each being preceded by an infectious illness. A second patient had a possible recurrence of the ARN syndrome in the same eye, one year after the original episode. Each episode was preceded by an upper respiratory infection and ipsilateral vesicular skin lesions on the face. Biopsy of one lesion yielded herpes simplex virus (HSV) in culture. These associations, although not definitive, do lend support to the hypothesis that HSV may be the cause of the ARN syndrome.

Cytomegalovirus retinitis

The appearances of cytomegalovirus retinitis are described in a body who was receiving maintenance immunosuppressive therapy for lymphatic leukaemia. The retinitis improved on cessation of the treatment and settled completely after an injection of lymphocyte dialysable transfer factor.

Necrotizing retinitis caused by opportunistic virus infection in a patient with Hodgkin's disease

A 33-year-old woman with Hodgkin's disease developed a painless progressive loss of vision in both eyes. Despite an ophthalmoscopic appearance of white-yellow retinal necrosis and retinal hemorrhage similar to that described with Hodgkin's disease, no sign of the disorder was found at autopsy. Instead, widespread evidence of Herpesviridae family virus infection was present in several organs, including the retinas. Opportunistic infection, including herpes simplex and cytomegalovirus, should be considered when retinitis complicates Hodgkin's disease.

Retinal aneurysms in adult cytomegalovirus retinitis

We observed aneurysms of the retinal arteries, capillaries, and venules occurring in a patient with cytomegalovirus retinitis. These aneurysms were caused by involvement of the retinal vascular endothelium resulting in focal weaknesses in the vascular walls. The clinical appearance of this retinitis superficially resembled retinal branch vein occlusion.

Cytomegalovirus retinitis in adults. A manifestation of disseminated viral infection

Retinitis caused by cytomegalovirus (CMV) infection is unusual in adults. Sixteen of the 17 cases reported have occurred in immunologically compromised patients, most frequently renal transplant recipients. CMV retinitis is associated with a distinctive ophthalmoscopic appearance and, in the majority of cases, was the first clinical manifestation of systemic viral infection. Severe and permanent visual deficits are characteristic. Since retinitis is a reliable sign of disseminated disease and ophthalmoscopic examination a rapid method of establishing its presence, recognition of this manifestation should allow earlier diagnosis of serious CMV infection.