Herpes simplex virus type 2 mediated acute retinal necrosis in a pediatric population: case series and review

Acute Retinal Necrosis Caused by Varicella Zoster Virus and Cytomegalovirus Co-Infection

PURPOSE

To report the clinical course of two cases of acute retinal necrosis (ARN) caused by varicella zoster virus (VZV) and cytomegalovirus (CMV) co-infection detected by polymerase chain reaction (PCR) on aqueous tap.

METHODS

Observational case reports.

RESULTS

Two patients presented to our services with unilateral panuveitis suggestive of ARN complicated by hemorrhagic vasculitis and started empirical therapy. Aqueous PCR was performed on the same day and showed double positivity for VZV and CMV, which guided treatment. At follow-up, wide-field color fundus imaging and high-resolution optical coherence tomography showed resolution of active retinitis.

CONCLUSION

Our cases suggest that ARN complicated by hemorrhagic vasculitis may be secondary to CMV and VZV co-infection, both in patients with an unremarkable clinical history and in those with immunodeficiency. In our cases, aqueous PCR testing was of paramount importance to determine the aetiology of ARN and to adjust the antiviral therapy accordingly.

Bilateral Optic Disc Edema as an Initial Presentation of Acute Retinal Necrosis

PURPOSE

We reported a case of acute retinal necrosis (ARN) that presented as isolated bilateral optic disc edema.

METHODS

A case report.

CASE

A 68-year-old male with a 3-day history of progressive blurred vision presented with isolated bilateral optic disc edema. Through history taking, we found that he was diagnosed with herpes zoster affecting the lumbar and sacral dermatomes in the past month. Five days later, the patient experienced acute deterioration in visual acuity, with the left eye deteriorating to perception of light only. Bilateral retinal necrosis was noticed. We tested the aqueous samples with polymerase chain reaction and identified positive varicella-zoster virus (VZV) results. A diagnosis of bilateral acute retinal necrosis caused by VZV infection was established and we administered intravitreal and intravenous antiviral medications, steroids, and performed prophylactic scleral buckling.

SUMMARY

This report demonstrates a rare ARN case initially presented with isolated bilateral optic disc edema.

The Host-Pathogen Interplay: A Tale of Two Stories within the Cornea and Posterior Segment

Ocular infectious diseases are an important cause of potentially preventable vision loss and blindness. In the following manuscript, we will review ocular immunology and the pathogenesis of herpesviruses and Pseudomonas aeruginosa infections of the cornea and posterior segment. We will highlight areas of future research and what is currently known to promote bench-to-bedside discoveries to improve clinical outcomes of these debilitating ocular diseases.

Rates of Herpes Simplex Virus Types 1 and 2 in Ocular and Peri-ocular Specimens

PURPOSE

To evaluate the rates of Herpes Simplex Virus types 1 (HSV-1) and 2 (HSV-2) in ocular specimens.

METHODS

Retrospective case series of all patients with a positive laboratory evaluation for ocular HSV performed at the Auckland District Health Board, Auckland, New Zealand between 1 January 2006 and 31 December 2017 were included in the study.

RESULTS

A total of 423 specimens were positive for HSV-1 (99.3%, n = 419) or HSV-2 (0.7%; n = 4). The majority of positive tests were identified through DNA amplification (n = 352; 83%) testing while the remainder were obtained by viral culture (n = 71; 17%). Ocular disease caused by HSV-2 in this study included acute retinal necrosis (n = 2), keratitis (n = 1), and blepharitis (n = 1).

CONCLUSIONS

HSV type 2 is a rare cause of ocular and peri-ocular infection but may cause severe, vision threatening disease.

Type I Interferon Signaling Is Critical During the Innate Immune Response to HSV-1 Retinal Infection

Purpose

Acute retinal necrosis (ARN) is a herpesvirus infection of the retina with blinding complications. In this study, we sought to create a reproducible mouse model of ARN that mimics human disease to better understand innate immunity within the retina during virus infection.

Methods

C57Bl/6J wild type (WT) and type I interferon receptor-deficient (IFNAR-/-) mice were infected with varying amounts of herpes simplex virus type 1 (HSV-1) via subretinal injection. Viral titers, optical coherence tomography (OCT) and fundus photography, the development of encephalitis, and ocular histopathology were scored and compared between groups of WT and IFNAR-/- mice.

Results

The retina of WT mice could be readily infected with HSV-1 via subretinal injection resulting in retinal whitening and full-thickness necrosis as determined by in vivo imaging and histopathology. In IFNAR-/- mice, HSV-1-induced retinal pathology was significantly worse when compared with WT mice, and viral titers were significantly elevated within two days after infection and persisted to day 5 after infection within the retina. These results were also observed in the brain where there were significantly higher viral titers and frequency of encephalitis in IFNAR-/- when compared to WT mice.

Conclusions

Collectively, these findings show that our new mouse model of ARN mimics human disease and can be used to study innate immunity within the retina. We conclude that type I interferons are critical in containing HSV-1 locally within retinal tissues and prohibiting spread into the brain.

Advances in the microbiological diagnosis of herpetic retinitis

Viral retinitis associated with herpesvirus is one of the most severe forms of uveitis and is a potentially sight-threatening ophthalmologic disease. The prognosis is poor and a rapid and aggressive management is necessary to improve the visual and sometimes vital prognosis of these patients. The treatments used are not without side effects, while many differential diagnoses exist, such as toxoplasmic retinochoroiditis, syphilitic retinitis, endogenous endophthalmitis and intraocular lymphoma. Causatives viruses are herpes simplex virus, varicella-zoster virus, and cytomegalovirus, which require rapid detection in ocular fluid, mainly aqueous humor. However, only a small amount of intraocular fluid is available for analysis. Advances in microbiological diagnostic techniques therefore were key factors in improving the management of these diseases. Historically, the diagnosis was based on immunological tests but more recently advances in molecular biology, in particular polymerase chain reaction, have played a crucial role to obtain a reliable and rapid diagnosis of viral retinitis associated with herpesvirus, as discussed in this review.

Acute retinal necrosis: A mini review

Acute retinal necrosis is a rare but potentially devastating disease. Even in the era of modern medicine, retinal detachment is a frequent complication leading to vison loss, as well as phthisis bulbi. Whereas IV acyclovir still remains the standard of care, high doses of valacyclovir with/without additional intravitreal injections of foscarnet have been used. In an attempt to reduce the retinal detachment rate, prophylactic laser treatment and early vitrectomy have been proposed. In this article, we aim to review current diagnostic and treatment modalities.

Case Report: Herpes Simplex Virus Type 2 Acute Retinal Necrosis With Viral Encephalitis in Children

Background

Few cases concerning acute retinal necrosis with viral encephalitis in children have been reported, especially cases where the fundus cannot be identified due to severe vitreous opacity in the early stage that makes diagnosis difficult.

Methods

We conducted a retrospective review of an unusual case of herpes simplex virus-2 (HSV-2) acute retinal necrosis with viral encephalitis in an immunocompetent child, along with a review of relevant literature published up to September 2021.

Result

An 11-year-old girl presented with an approximate 20-day history of ocular redness and decreased visual acuity in the left eye. Examination revealed anterior uveitis and vitreous opacity in the left eye. An anterior chamber tap was performed because the fundus could not be observed clearly, and the aqueous humor was positive for HSV-2 DNA. Cerebrospinal fluid also tested positive for HSV-2. She was diagnosed with acute retinal necrosis syndrome and viral encephalitis. The condition was controlled with timely antiviral and steroid therapy. She was also treated with prophylactic laser therapy to prevent retinal detachment during subsequent follow-up. The pathogenesis, diagnosis, and treatment of HSV-2 acute retinal necrosis in children and the association between acute retinal necrosis and viral encephalitis are further discussed, based on published literature.

Conclusion

HSV-2-related pediatric acute retinal necrosis may be due to the acquisition of subclinical infection with HSV-2 during parturition, followed by reactivation of the virus latent in the body on account of certain factors. Moreover, it may be complicated with viral encephalitis. For suspected cases with invisible fundus, early intraocular fluid examination is especially helpful for differential diagnosis. Early diagnosis, early treatment, and timely prophylactic laser treatment to prevent retinal detachment are key to a better prognosis. Physicians need to pay attention to such suspected cases during diagnosis and treatment.

Acute Retinal Necrosis: Clinical Features, Diagnostic Pitfalls, Treatment, and Outcome of an Insidious Disease in Children. Case Report and Review of the Literature

OBJECTIVE

This study aims to explore clinical features, diagnostic work-up, treatment, and outcomes of pediatric patients with acute retinal necrosis (ARN), and to propose a standardized management of this condition in childhood.

METHODS

Clinical manifestations, diagnostic work-up, and treatment of three pediatric cases with ARN were analyzed. Furthermore, a review of the literature was performed from January 1990 to November 2021, focused on 1) clinical presentation; 2) differential diagnosis, including both infectious and non-infectious conditions; 3) key role of diagnostic techniques; and 4) currently available treatments.

RESULTS

Data from 72 children with ARN (69 from literature and 3 from our center) were analyzed. The most frequent presenting symptoms were red eye resistant to topical treatment (57%) and altered vision (58%), 25 patients had bilateral involvement. In 30% a known history of herpetic infection was reported. PCR testing on anterior chamber and/or vitreous sampling was performed in 46 cases (64%) and was diagnostic in 88% of them, with herpes simplex virus (HSV) 2 being the most frequently identified pathogen (57%). All patients underwent systemic antiviral therapy (16% only oral); adjunctive intravitreal injections were performed in 21% of them.

CONCLUSIONS

ARN is a rare but severe ocular infection presenting as a panuveitis with occlusive retinal vasculitis and peripheral retinal necrosis. Varicella-zoster virus and HSV 1-2 are most frequently implicated. Due to a high incidence of rhegmatogenous retinal detachment and optic atrophy, ARN has a poor prognosis with a potentially severe impact on visual function. Although a prompt recognition is crucial to prevent complications, ARN diagnosis in children is still challenging.

Multimodal Imaging of a Severe Case of Neonatal Acute Retinal Necrosis and Lens Vacuoles Associated with Herpes Simplex Virus Infection

PURPOSE

To report a case of a neonate with acute retinal necrosis, lens vacuoles, and encephalitis associated with herpes simplex virus (HSV) infection.

DESIGN

Case report.

METHODS

Retrospective chart review.

RESULTS

A male neonate was brought for screening for retinopathy of prematurity at the corrected age of 32 weeks. Slit-lamp examination showed lens vacuoles in both eyes. Fundus examination revealed extensive retinal detachments with prominent retinal whitening, subretinal exudates, and retinal hemorrhage. Computed tomography of the brain showed encephalomalacia. Polymerase chain reaction of cerebrospinal fluid and anterior chamber fluid was both positive for HSV-1. Despite systemic anti-viral therapy, a rhegmatogenous retinal detachment and subsequent proliferative vitreoretinopathy developed in the patient's right eye. The retinal detachment in the left eye resolved, but significant chorioretinal degeneration occurred. With time lens vacuoles decreased in number.

CONCLUSIONS

Clinicians should remember this rare, but devastating condition without specific prodromal symptoms.

Immune Cell Status and Cytokines Profiles in Patients with Acute Retinal Necrosis

Purpose: To assess the immune status of acute retinal necrosis (ARN) patients and to investigate the immune cell types involved in the immunopathogenesis.Methods: Peripheral blood and intraocular fluid were collected from 17 ARN patients and 9 control subjects. The Percentage of immune cells was measured using flow cytometry, levels of complement and antibodies were determined by rate nephelometry, and cytokine levels in the serum and aqueous humor (AH) were detected using cytokine quantitative chips. Data were analyzed using SPSS 23.0. p < .05 was considered statistically significant.Results: Proportion of T-helper 17 cells (p = .034) in serum and concentrations of multiple cytokines associated with Th17 cells (IL-6, IL-17, IL-17 F, IL-21, IL-22) in AH and serum were elevated of ARN patients.Conclusion: Th17 cells appeared to participate in the development of ARN. We found inflammatory cytokines and cells were elevated in the serum and AH of ARN patients.

Varicella-zoster virus necrotising retinitis, retinal vasculitis and panuveitis following uncomplicated chickenpox in an immunocompetent child

A 4-year-old girl presented with acute left visual loss 4 weeks after uneventful chickenpox. She was found to have left necrotising retinitis and profound retinal vasculitis and vitritis. Aqueous humour was PCR positive for varicella-zoster virus. Combined intravenous and intravitreal antiviral treatment led to rapid improvement with settled retinitis, no vascular occlusion and good recovery of vision. Her recent coinfection with Epstein-Barr virus may have acted to provoke the retinitis.

Intraocular Detection of Herpes viruses by xTAG Liquid Chip Technology in Patients with Acute Retinal Necrosis

PURPOSE

To evaluate the performance of the xTAG liquid chip technology (xTAG-LCT) for etiological diagnosis of acute retinal necrosis (ARN).

METHODS

Fifteen vitreous and 3 aqueous samples from 18 ARN patients were analyzed by xTAG-LCT and multiplex PCR (mPCR)/quantitative PCR (qPCR).

RESULTS

xTAG-LCT revealed positive results in 17 of the 18 samples: 10 for Varicella Zoster Virus (VZV) alone; 5 for VZV and Epstein-Barr virus (EBV); 1 for herpes simplex viruses type 1 (HSV-1) and EBV; 1 for VZV, HSV-1 and EBV. While mPCR revealed the same results as xTAG-LCT for VZV and HSV-1 in all samples, only 2 of the 7 samples positive for EBV on xTAG-LCT were confirmed by qPCR. None of the 28 control vitreous samples from 8 non-ARN patients and 10 pair of cadaveric eyes was positive for any of the tested viruses.

CONCLUSIONS

xTAG-LCT could be a useful alternative for etiological diagnosis of ARN.

Unusual retinopathy in a child with severe combined immune deficiency

We describe a case of an infant diagnosed with severe combined immune deficiency (Adenosine Deaminase (ADA), SCID) with severe retinopathy and associated low vision in both eyes at first examination. An extensive infectious work up revealed an enterovirus infection, which suggested an early infectious and severe retinopathy. Genetic causes of congenital retinitis pigmentosa/ Leber's congenital amaurosis could be excluded by whole exome sequencing.

Delayed recurrence of acute retinal necrosis (ARN): A case series

PURPOSE

To report five cases of acute retinal necrosis (ARN) that reactivated in the same eye or presented in the contralateral eye between two and nineteen years after the initial episode of acute retinal necrosis.

CASES

Five patients with a previous history of ARN developed recurrent ARN infection following a lengthy latency period. In all five patients who initially presented with unilateral disease, four developed infection in the contralateral eye and one developed recurrent infection in the ipsilateral eye. Latency periods ranged from two to nineteen years, and final visual acuity in the affected eyes ranged from 20/30 to no light perception. Each patient was treated with antiviral medication for both the initial infection and for subsequent reactivations, but was not on long-term prophylaxis at the time of recurrent disease.

CONCLUSION

Although rare, delayed onset reactivation of ARN can occur in either the same eye or contralateral eye despite adequate treatment. While contralateral spread of initial infection is fairly common, these reactivations rarely occur more than six weeks after initial infection. Currently there are no guidelines for use of prophylactic antiviral medication to prevent late recurrence of ARN.

Current aspects on the management of viral uveitis in immunocompetent individuals

Viruses are a fundamental etiology of ocular inflammation, which may affect all structures of the organ. Advances in molecular diagnostics reveal an increasingly broader spectrum of virus-associated intraocular inflammation, including all members of the herpes family, rubella virus, and other more rare causes such as Epstein–Barr and chikungunya virus. In particular, viruses of the herpes family are important causes of anterior and posterior uveitis. Owing to their often fulminant clinical course and persistence in ocular tissues, a clear differential diagnosis between alpha- and beta-type herpes viruses is essential to guide acute and long-term treatment. Here, we review the epidemiology, clinical, and laboratory findings of virus-associated uveitis with emphasis on their therapy and management and include our own experience.

Emerging techniques for pathogen discovery in endophthalmitis

PURPOSE OF REVIEW

Despite the inability to detect certain organisms and relatively low yield, microbial culture is the current gold standard for the diagnosis of most intraocular infections. Research on alternative molecular diagnostic methods has produced an array of strategies that augment and improve pathogen detection. This review summarizes the most recent literature on this topic.

RECENT FINDINGS

The yield of traditional microbial culture has not improved since the Endophthalmitis Vitrectomy Study results were published 20 years ago. Advances in PCR methods have enabled quantification of pathogen load and screening for multiple organisms at once. More recently, deep sequencing techniques allow highly sensitive detection of any DNA-based life form in a specimen. This offers the promise of not only improved detection of traditional organisms but can also identify organisms not previously associated with endophthalmitis.

SUMMARY

Molecular diagnostic methods enhance the results of microbial culture and may become the new standard in the diagnosis of intraocular infections.

Gender disparities in ocular inflammatory disorders

Ocular inflammatory disorders disproportionately affect women, and the majority of affected women are of childbearing age. The role of sex or reproductive hormones has been proposed in many other inflammatory or autoimmune disorders, and findings from non-ocular autoimmune diseases suggest a complex interaction between sex hormones, genetic factors and the immune system. However, despite the age and sex bias, factors that influence this disparity are complicated and unclear. This review aims to evaluate the gender disparities in prevalence, incidence and severity of the most common infectious and non-infectious ocular inflammatory disorders.

Sex and reproduction in the transmission of infectious uveitis

Current data permit only speculations regarding sex differences in the prevalence of infectious uveitis between women and men because uveitis case surveys do not uniformly report gender data. Differences in prevalence that are reported in the literature could relate to simple differences in the number of women and men at risk for infection or to biological differences between men and women. Compared to other types of uveitis, infectious uveitis may be directly related to occupational exposures or sexual behaviors, which differ between women and men, and may mask actual biological differences in susceptibility to ocular manifestations of the infection and its prognosis. In infectious uveitis for which there is no element of sexual transmission and data is available, prevalence of ocular disease is roughly equal between women and men. Women also have a unique relationship with infectious uveitis in their role as mothers. Vertical transmission of infections such as herpes simplex, toxoplasmosis, and cytomegalovirus can produce severe chorioretinitis in neonates.

Acute retinal necrosis in childhood

Background

Acute retinal necrosis (ARN) is a viral syndrome consisting of uveitis/vitritis, occlusive vasculitis and peripheral necrosis. Few incidents are reported in children. The etiology is reactivated herpes simplex virus (HSV) or varicella-zoster virus (VZV). Treatment with acyclovir is often used. The administration of oral glucocorticosteroids is of unproven benefit. Prognosis is variable but poor.

Methods

Three weeks after contracting mild chickenpox, a healthy 4-year-old girl developed blurred vision in her right eye. Severely reduced visual acuity was noted, together with anterior uveitis, ‘mutton-fat’ precipitates and vitral flare. Retinal vasculitis with necrosis was present. Serology for toxoplasma, cytomegalovirus and HIV was negative, while HSV and VZV IgG antibodies were positive. She was treated with 30 mg/kg of intravenous methylprednisolone (3 days), 30 mg of oral prednisone (3 days), and tapering for 8 weeks. Intravenous acyclovir was given for 10 days, followed by oral acyclovir for 4 months. Aspirin (100 mg/day) was given for 4 months.

Results

At 12 months, the girl felt good. Her right eye acuity was 6/9, with an intraocular pressure of 17 mm Hg. The peripheral retina showed scarring but no detachment.

Conclusions

This is the first report of a once-daily high-dose methylprednisolone pulse therapy in one of the youngest known ARN cases. Pulsed steroid therapy was based on its known effectiveness in vasculitis, which is the main pathophysiology in ARN. There was no evidence of steroid-related viral over-replication. Our case achieved an excellent clinical and ophthalmic recovery in spite of the poor prognosis. The positive result of this case report provides a basis for further evaluation of high-dose steroid pulse therapy in ARN.

Neonatal herpes simplex virus type-1 central nervous system disease with acute retinal necrosis

We report a case of neonatal herpes simplex virus (HSV)-1 central nervous system disease with bilateral acute retinal necrosis (ARN). An infant was presented at 17 days of age with focal seizures. Cerebrospinal fluid polymerase chain reaction was positive for HSV-1 and brain magnetic resonance imaging showed cerebritis. While receiving intravenous acyclovir therapy, the infant developed ARN with vitreous fluid polymerase chain reaction positive for HSV-1 necessitating intravitreal foscarnet therapy. This is the first reported neonatal ARN secondary to HSV-1 and the first ARN case presenting without external ocular or cutaneous signs. Our report highlights that infants with neonatal HSV central nervous system disease should undergo a thorough ophthalmological evaluation to facilitate prompt diagnosis and immediate treatment of this rapidly progressive sight-threatening disease.