Decrease in the risk of bilateral acute retinal necrosis by acyclovir therapy

Retinitis following varicella in a vaccinated child with acute lymphoblastic leukemia

Serious ocular disease following varicella (chickenpox) is rare in children. In addition, retinitis in children with hematologic malignancies may present a difficult diagnostic challenge because infectious retinitis may mimic leukemic involvement of the eye. We report a 7-year-old patient with T-cell acute lymphoblastic leukemia in remission who presented with visual complaints 2 weeks after developing chickenpox. Ophthalmologic evaluation revealed acute retinitis in the right eye. Prolonged therapy with acyclovir resulted in near complete recovery. Early diagnosis of VZV retinopathy and aggressive antiviral treatment is critical to prevent acute and long-term ocular sequelae.

Ocular association of HIV infection in the era of highly active antiretroviral therapy and the global perspective

Ocular involvement is a common complication of HIV infection. Since the late 1990s, widespread use of highly active antiretroviral therapy (HAART) has altered the spectrum, and reduced the incidence of ocular involvement in developed countries. The incidence of the most common ocular opportunistic infection, cytomegalovirus retinitis, has decreased tremendously. However, immune recovery uveitis secondary to HAART has emerged as a frequent visually threatening condition. Early diagnosis and treatment with periocular steroids is helpful in minimizing visual loss. Clinicians should also be aware that certain antimicrobial agents used to treat opportunistic infections in HIV-positive patients are associated with potentially serious ocular side effects. In developing countries, where most of the world's 40 million HIV-positive patients live, the spectrum and incidence of ocular involvement differ from those in developed countries. The lack of HAART availability is among the many causes of these differences, which may include nutritional factors, basic medical care availability and the levels of exposure to different infectious agents. These factors add to the already challenging task of treating ocular complications and preventing blindness in HIV-positive patients in developing countries.

Progression of varicella-zoster virus necrotizing retinopathy in an HIV-negative patient with transient immune deviation

PURPOSE

To report a case of unilateral varicella-zoster virus (VZV) necrotizing retinopathy that progressed from outer retinitis with features of progressive outer retinal necrosis (PORN) to typical acute retinal necrosis (ARN) in an HIV-negative patient with a transient decrease in CD4 lymphocyte counts and CD4/CD8 ratio.

METHOD

Case report.

RESULTS

A 41-year-old Chinese man presenting with blurred vision in the right eye was diagnosed with herpetic necrotizing retinitis without vitritis. Fundus examination revealed retinal arteritis and extensive deep whitish retinal lesions in the mid-periphery with minimal vitritis. Aqueous humor and vitreous PCR were positive for VZV. His CD4 count on presentation was depressed (239 cells/ul) and the CD4/CD8 ratio was low (0.8). The referring ophthalmologist had treated him with prednisolone 60 mg/day. At our institution, when intravenous acyclovir was started and the steroid therapy discontinued, he developed severe vitritis and the deep retinal lesions progressed to full-thickness retinitis typical of ARN. Repeat CD4 count was 512 cells/ul at day 14. In total, he was treated with 14 days of i.v. acyclovir (12 mg/kg 8-hourly) followed by oral valaciclovir 500 mg three times a day for 3 months. Prednisolone 30 mg once daily was restarted and tapered over 3 months. Despite prophylactic argon retinal photocoagulation to the edge of the retinitis, the patient developed a total retinal detachment at 3 months.

CONCLUSIONS

VZV retinal infection in an HIV-negative patient with transient immune deviation can manifest initially as outer retinitis with features similar to PORN and progress to typical ARN when CD4 counts return to normal.

Rétinites nécrosantes herpétiques

The diagnosis of necrotic herpetic retinitis is suggested on clinical grounds, prompting urgent appropriate intravenous and intravitreal treatment. PCR on ocular samples is most often successful in identifying the herpetic agent. Classic acute retinal necrosis syndrome caused by herpes simplex or zoster virus and the different clinical forms present in immunocompetent or immunodepressed patients are described. The differential diagnosis includes atypical presentation of retinal necrosis caused by toxoplasmosis, syphilis, or ocular lymphoma; the ocular samples are useful in establishing the etiological diagnosis. We describe the different therapeutic strategies in the acute phase and as secondary prophylactic treatment. The clinical outcome appears to be influenced by rapid, appropriate treatment, limiting the extension of the retinal necrosis.

Prise en charge diagnostique et thérapeutique des rétinites nécrosantes herpétiques

PURPOSE

To study the viral cause and present the management of necrotizing herpetic retinopathies.

METHODS

Charts of patients presenting with acute retinal necrosis (ARN) or progressive outer retinal necrosis (PORN) diagnosed between March 1997 and June 2001 were retrospectively reviewed. Intraocular specimens were obtained in 33 cases to determine the viral cause using polymerase chain reaction-based assays and/or detection of intraocular antibody production.

RESULTS

The mean age was 43.4 Years. Herpesvirus genome was identified in 29 patients (80.5%). In the ARN group (32 patients, 38 eyes), herpes simplex virus (HSV) DNA was found in 11 patients (34.4%), varicella-zoster virus (VZV) in nine patients (28.1%), and cytomegalovirus (CMV) in four patients (12.5%). One patient (3.1%) presented an Epstein-Barr virus (EBV) infection. ARN was bilateral at initial examination in six patients and secondary bilateralization was observed in four patients. In the PORN group (four patients, eight eyes), the retinitis was bilateral and VZV DNA was detected in all cases. Two patients were treated with intravenous acyclovir, six with foscarnet alone, ten with intravenous foscarnet + acyclovir, 18 with intravenous foscarnet and intravitreous ganciclovir injections. Complications of necrotizing herpetic retinitis were cataract (26%), optic nerve atrophy (23.9%), and retinal detachment (17.4%). Final visual acuity was less or equal to 20/200 in 47.8% of cases.

CONCLUSIONS

It is important to determine the specific viral etiology since progression and prognosis may be different in herpetic necrotizing retinitis caused by HSV, VZV, or CMV. Visual prognosis is improved by intensive antiviral therapy, but remains poor if complications occur.

Nécrose rétinienne aiguë : présentation clinique, modalités de prise en charge et pronostic à partir d’une série de 22 patients

PURPOSE

To evaluate the clinical outcome and medical management in a series of patients diagnosed with acute retinal necrosis.

MATERIAL AND METHODS

Between 1993 and 2000, 22 patients suffering from acute retinal necrosis were referred to our department. We retrospectively reviewed the clinical course, delay between diagnosis and first clinical manifestation, biological profiles, treatment and complications.

RESULTS

All patients had vitreous inflammation; retinitis was seen upon examination in 82% of the cases. Nevertheless, for six patients (27% of the cases), failure to recognize the diagnosis led to delay (mean, 5.5 days) between the first ophthalmological examination and antiviral therapy. Nineteen patients underwent laboratory evaluation, and virological diagnosis was made in 16 of them: varicella zoster virus was found in 11 cases, herpes simplex type 1 in three cases, and herpes simplex type 2 and cytomegalovirus in one case each. Nine patients were treated with a combination of aciclovir and foscarnet and 13 with aciclovir alone. Among the 16 patients who received aciclovir, one did not respond to therapy after 2 days and was cured only after foscarnet was added. Recurrence occurred at the end of treatment in only one patient. Retinal detachment complicated the course for 11 patients and was always associated with proliferative vitreoretinopathy. Among those, seven of the ten patients who accepted surgery were successfully treated. Eleven out of 22 patients had a final visual acuity up to 20/200 and two up to 20/40.

CONCLUSION

In our series, acyclovir alone was sufficient to cure the majority of cases. Even with antiviral therapy, the prognosis of acute retinal necrosis remains poor. Retinal detachment is the main complication.

Varicella-zoster virus: atypical presentations and unusual complications

Varicella-zoster virus (VZV) is the etiologic agent of varicella (primary infection) and herpes zoster (reactivation of latent infection). Although varicella is most often a relatively benign and self-limited childhood illness, the disease can be associated with a variety of serious and potentially lethal complications in both immunocompetent and immunocompromised persons. One complication of varicella that appears to be increasing in frequency is serious bacterial soft tissue infections caused by group A streptococci. Issues related to management of varicella become especially complex when varicella involves pregnant women or susceptible neonates. Herpes zoster can be associated with a variety of neurologic complications, including a syndrome of delayed contralateral hemiparesis. Neurologic complications of herpes zoster, including chronic encephalitis, occur with increased frequency in AIDS patients. VZV retinitis is a potentially sight-threatening complication that occurs in both immunocompetent and immunocompromised persons. Current knowledge regarding pathogenesis and antiviral therapy is reviewed.

Herpes simplex virus type 1 encephalitis associated with acute retinal necrosis syndrome in an immunocompetent patient

PURPOSE

The onset of acute retinal necrosis secondary to herpes simplex encephalitis is exceptional. We report such an association in an immunocompetent patient, in whom the genome of herpes simplex virus type 1 (HSV-1) was identified successively at both sites of infection.

METHODS

Polymerase chain reaction (PCR) assay of HSV-1 in cerebrospinal fluid (CSF) and aqueous humour.

RESULTS

An immunocompetent patient aged 40 years presented with HSV-1 encephalitis, which was confirmed by imaging, viral serology and identification of the HSV-1 genome in the CSF. The subject's immunological profile was normal. The patient was treated with foscavir. Six weeks after clinical recovery and negative PCR, the patient presented with a unilateral acute retinal necrosis syndrome. Polymerase chain reaction of the aqueous humour was positive, while serology and PCR of the CSF remained negative.

CONCLUSION

Identification of the HSV-1 genome at the two successive sites of infection stresses the possibility of brain-to-eye transmission of HSV-1.

Acute retinal necrosis syndrome in a child

We recently cared for an 11-year-old child with acute retinal necrosis syndrome, an ophthalmologic condition characterized by the triad of anterior uveitis, occlusive retinal vasculitis and progressive peripheral retinal necrosis. Acute retinal necrosis syndrome occurs primarily in nonimmunocompromised adults as a result of reactivated herpes simplex or varicella-zoster virus infection. Antiviral and antiinflammatory therapy appears to reduce the incidence of vision-threatening retinal necrosis and involvement of the contralateral eye.

Viral causes of the acute retinal necrosis syndrome

Acute retinal necrosis has been described as a clinical entity for nearly 30 years. Acute retinal necrosis is a potentially visually devastating necrotizing vaso-occlusive retinitis affecting both healthy and immunocompromised patients. Acute retinal necrosis is caused by the herpes group of viruses, mainly varicella zoster, herpes simplex types 1 and 2, and, rarely, cytomegalovirus. Recently, polymerase chain reaction techniques have enabled detection of very small amounts of viral DNA from intra-ocular fluid samples. This can help in both the diagnosis of atypical cases of retinitis and uveitis and directing treatment in cases of acute retinal necrosis.

Neuronal pathways for the propagation of herpes simplex virus type 1 from one retina to the other in a murine model

Herpetic retinitis in humans is characterized by a high frequency of bilateral localization. In order to determine the possible mechanisms leading to bilateral retinitis, we studied the pathways by which herpes simplex virus type 1 (HSV-1) is propagated from one retina to the other after intravitreal injection in mice. HSV-1 strain SC16 (90 p.f.u.) was injected into the vitreous body of the left eye of BALB/c mice. Animals were sacrificed 1, 2, 3, 4 and 5 days post-inoculation (p.i.). Histological sections were studied by immunochemical staining. Primary retinitis in the inoculated eye (beginning 1 day p.i.) was followed by contralateral retinitis (in the uninoculated eye) starting at 3 days p.i. Infected neurons of central visual pathway nuclei (lateral geniculate nuclei, suprachiasmatic nuclei and pretectal areas) were detected at 4 days p.i. Iris and ciliary body infection was minimal early on, but became extensive thereafter and was accompanied by the infection of connected sympathetic and parasympathetic pathways. The pattern of virus propagation over time suggests that the onset of contralateral retinitis was mediated by local (non-synaptic) transfer in the optic chiasm from infected to uninfected axons of the optic nerves. Later, retinopetal transneuronal propagation of the virus from visual pathways may have contributed to increase the severity of contralateral retinitis.

HSV-1--induced acute retinal necrosis syndrome presenting with severe inflammatory orbitopathy, proptosis, and optic nerve involvement

OBJECTIVE

To present a unique case in which orbital inflammation, proptosis, and optic neuritis were the initial symptoms of acute retinal necrosis (ARN). The clinical presentation of ARN, as well as the currently recommended diagnostic procedures and guidelines for medical treatment of ARN, are summarized.

DESIGN

Interventional case report.

TESTING

Polymerase chain reaction (PCR) techniques were made on the vitreous for cytomegalovirus, Epstein-Barr virus, herpes simplex virus (HSV), varicella zoster virus, and toxoplasmosis. A full laboratory evaluation was made together with HLA-typing and serologic tests measuring convalescent titers for HSV and other micro-organisms. Magnetic resonance imaging scan, computed tomography (CT) scan, and fluorescein angiographic examination were performed. The patient was treated with acyclovir and oral prednisone.

MAIN OUTCOME MEASURES

The patient was evaluated for initial and final visual acuity and for degree of proptosis, periocular edema, and vitreitis.

RESULTS

The first symptoms and signs of ARN were eye pain, headache, proptosis, and a swollen optic nerve on CT scan. Other than increased C-reactive protein, all blood samples were normal. PCR was positive for HSV-type I in two separate vitreous biopsies. The patient had the strongly ARN-related specificity HLA-DQ7.

CONCLUSIONS

This is the first report of HSV-induced ARN presenting with inflammatory orbitopathy and optic neuritis. Polymerase chain reaction for HSV-1 was positive more than 4 weeks after debut of symptoms, which is a new finding. The combination of severe vitreitis and retinal whitening, with or without proptosis, should alert the clinician to the possibility of herpes infection and treatment with intravenous acyclovir started promptly.

Varicella zoster virus retrobulbar optic neuritis preceding retinitis in patients with acquired immune deficiency syndrome

OBJECTIVE

This study aimed to describe a recently recognized and rare presentation of varicella zoster virus (VZV) retrobulbar optic neuritis preceding retinitis in patients with acquired immune deficiency syndrome and to identify factors that may relate to improved visual outcome.

METHODS

Diagnosis, treatment, and clinical course are described for three eyes of two patients with this viral infection.

RESULTS

Patients had decreased vision, headache, and recent zoster dermatitis. Varicella zoster virus retrobulbar optic neuritis was diagnosed on the bases of clinical, laboratory, and electrophysiologic examination results. Profound vision loss and peripheral retinitis ensued despite intravenous antiviral treatment. Combination intravenous and intravitreous antiviral injections were administered with dramatic visual recovery.

CONCLUSIONS

Varicella zoster virus retrobulbar optic neuritis should be considered in immunocompromised patients with visual loss. Early diagnosis and aggressive combination therapy via systemic and intravitreous routes may enable return of useful vision.

Pharmacomanipulation of HSV-1 induced chorioretinitis in mice

In the von Szily mouse model, intracameral inoculation of herpes simplex virus type-1 (HSV-1) results in inflammation of the ipsilateral anterior segment with relative chorioretinal sparing and destructive contralateral chorioretinitis. We studied the effect of the systemic antiviral agent acyclovir (ACV) and anti-HSV-1 antibody therapy in this model. Contralateral chorioretinitis developed in none of the 18 mice receiving ACV from post-inoculation day (pid) 1 (p < 0.0001), in 6 of 10 (60%) mice when treatment was delayed until pid 7 (p = 0.40) and in 14 of 18 (77%) controls. Contralateral disease developed in 8 of 16 (50%) mice that received anti-HSV-1 antibody from pid 1 (p = 0.02), in 13 of 16 (81%) treated from pid 5 (p = 0.64), in 7 of 8 (87.5%) treated from pid 7 (p = 1.0) and in 17 of 20 (85%) controls. We conclude that early treatment with ACV or anti-HSV-1 antibody reduces the incidence of contralateral chorioretinitis in mice.

Delayed fellow eye involvement in acute retinal necrosis syndrome

PURPOSE/METHOD

We studied a case of acute retinal necrosis in which a 30-year delay occurred between involvement of the first and fellow eyes. After systemic treatment with acyclovir and prednisolone, the fellow eye developed a retinal detachment requiring vitrectomy and silicone oil tamponade.

RESULTS/CONCLUSION

The fellow eye retained a useful Snellen acuity of 20/120. In a patient who has had acute retinal necrosis, any symptoms or signs in the fellow eye, even several decades later, should alert the examining physician to the possibility of delayed involvement of the fellow eye.

Clinical and histopathologic study of varicella zoster virus retinitis in patients with the acquired immunodeficiency syndrome

Varicella zoster virus retinitis in patients with the acquired immunodeficiency syndrome is known to be a devastating disease. We studied a series of six consecutive patients that sheds new light on the clinical manifestations and treatment options of this disorder. All patients had episodes of cutaneous zoster, long-term exposure to oral acyclovir, and CD4+ T lymphocyte counts less than 50 cells/mm3. Two of the six patients had simultaneous radiographically demonstrable and histologically proven varicella zoster virus encephalitis; this is an important association. Histologic examination of autopsy specimens disclosed that the retinal infection by varicella zoster virus involves the retinal pigment epithelium more heavily than the inner retina, which is consistent with the characteristic clinical impression of an outer retinal necrosis.

The progressive outer retinal necrosis syndrome. A variant of necrotizing herpetic retinopathy in patients with AIDS

BACKGROUND

The progressive outer retinal necrosis syndrome is a recently recognized variant of necrotizing herpetic retinopathy. This report characterizes more fully its clinical features and course.

METHODS

Using standardized clinical criteria, patients with progressive outer retinal necrosis syndrome from four institutions were identified. Patient records were reviewed retrospectively for the following data: medical and demographic characteristics, presenting symptoms, physical findings, course, responses to treatment, and outcomes.

RESULTS

Thirty-eight patients (65 involved eyes) were studied. All had acquired immune deficiency syndrome. A known history of cutaneous zoster was documented in 22 (67%) of 33 patients. Median CD4 lymphocyte count was 21/mm3 (range, 0-130/mm3). Median follow-up was 12 weeks. The most common presenting symptom was unilateral decreased vision (35 of 65 eyes, 54%); median visual acuity at presentation was 20/30 (range, 20/20 to no light perception [NLP]). Anterior chamber and vitreous inflammatory reactions were absent or minimal in all patients. Typical retinal lesions were multifocal, deep opacities scattered throughout the periphery, although macular lesions also were present in 21 eyes (32%) at diagnosis. Lesions progressed rapidly to confluence. Initial intravenous antiviral therapy appeared to reduce disease activity in 17 (53%) of 32 eyes, but treatment did not alter final visual outcome. Visual acuity was NLP in 42 (67%) of 63 eyes within 4 weeks after diagnosis. Retinal detachment occurred in 43 (70%) of 61 eyes, including 13 (93%) of 14 eyes that received prophylactic laser retinopexy.

CONCLUSION

The progressive outer retinal necrosis syndrome is characterized by features that distinguish it from cytomegalovirus retinopathy, acute retinal necrosis syndrome, and other necrotizing herpetic retinopathies. Visual prognosis is poor with current therapies.

Recurrence of presumed varicella-zoster virus retinopathy in patients with acquired immunodeficiency syndrome

Five patients with acquired immunodeficiency syndrome (AIDS) and presumed varicella-zoster virus retinopathy had recurrence of retinopathy after stabilization with initial intravenous antiviral therapy. Recurrences were recognized as increased retinal opacification at the borders of preexisting lesions or as new lesions. In four of the five patients, recurrences were temporally associated with a reduction in the amount of antiviral medication being received. Changes included switch from intravenous to oral acyclovir (two patients), taper of oral acyclovir (one patient), and discontinuation of medications (one patient). In four patients disease was initially unilateral; in three of these four, disease subsequently developed in the previously unaffected fellow eye at the time of recurrence. The median time from stabilization of disease to recurrence was 51 days (range, 14 to 90 days). In contrast to the management of varicella-zoster virus retinopathy in immunocompetent patients and varicella-zoster virus lesions of the skin, varicella-zoster virus retinopathy in patients with AIDS appears to require chronic suppressive antiviral therapy to prevent recurrences. In this respect it is similar to other opportunistic retinal infections in patients with AIDS. The best drugs and optimal treatment regimens for maintenance antiviral therapy remain unknown.

Systemic antiviral drugs used in ophthalmology

Over the past two decades, the recognition of viral enzymes and proteins that can serve as molecular targets of drugs has revolutionized the treatment of viral infections. Beginning with acyclovir, a number of systemically administered agents which are both relatively safe and effective for the treatment of herpetic infections and human immunodeficiency virus (HIV) infections have become widely available. Because of increased numbers of herpes virus infections, as well as the rising epidemic of HIV infections, the ophthalmologist is, more likely than ever before to be involved in the treatment of severe and frequent ocular infections caused by herpes viruses. In addition, the acute retinal necrosis (ARN) syndrome has been demonstrated to be caused by herpes viruses and a once rare retinal infection caused by cytomegalovirus is common in patients with the acquired immunodeficiency syndrome (AIDS). In this article, four systemic antiviral drugs (Vidarabine, Acyclovir, Ganciclovir, and Foscarnet) that have demonstrated usefulness in the treatment of ophthalmic disease are reviewed in detail with regard to their mechanisms, applications, effectiveness, and side effects.