Incidence, recurrence, and outcomes of herpes simplex virus eye disease in Olmsted County, Minnesota, 1976-2007: the effect of oral antiviral prophylaxis

[Corneal wound healing-Pathophysiology and principles]

The cornea forms the anterior border of the eye and significantly contributes to a sharp optical image quality on the retina through its transparency, avascular nature and curvature. Because of its anatomical structure and as a barrier to the environment, the cornea is particularly exposed to various external factors, such as injuries and pathogens. A correct wound healing without the formation of light diverging scarring is therefore essential to preserve the integrity and function of the cornea. Misguided wound healing is of outstanding clinical relevance and can lead to corneal fibrogenesis. Corneal fibrosis results in scarring with a loss of optical transparency, which significantly reduces eyesight and can lead to blindness. Understanding the pathophysiological mechanisms of wound healing and fibrogenesis is of great importance for the diagnostics, treatment and evaluation of the subsequent healing process in order to prevent permanent damage as far as possible.

Viral anterior uveitis

Viral anterior uveitis (VAU) needs to be suspected in anterior uveitis (AU) associated with elevated intraocular pressure, corneal involvement, and iris atrophic changes. Common etiologies of VAU include herpes simplex, varicella-zoster, cytomegalovirus, and rubella virus. Clinical presentations can vary from granulomatous AU with corneal involvement, Posner-Schlossman syndrome, Fuchs uveitis syndrome, and endothelitis. Due to overlapping clinical manifestations between the different viruses, diagnostic tests like polymerase chain reaction and Goldmann-Witmer coefficient analysis on the aqueous humor may help in identifying etiology to plan and monitor treatment.

20 years since the Herpetic Eye Disease Study: Lessons, developments and applications to clinical practice

Herpes Simplex Virus (HSV) is the most common virus that causes eye disease. Although around 60% of the world's population are seropositive for HSV antigens, fortunately, it is estimated that only 1% of seropositive individuals develop eye disease. The most common ocular manifestation of HSV is keratitis, while uveitis and retinal necrosis occur in a small number of cases. HSV keratitis is a debilitating disease, for several reasons: pain , photophobia, and vision loss in acute disease, latency of the virus which leads to infection reactivation from various triggers, scarring, and neovascularisation, leading to permanent vision loss with poor visual rehabilitation prospects. The Herpetic Eye Disease Study (HEDS) was a landmark series of randomised controlled trials in the 1990s that set the benchmark for evidence-based treatment guidelines for anterior eye herpetic disease. Since this time, there has been a change in the distribution of seroprevalence of herpes in the community, a simplified diagnostic classification, advances in treatment options, an emergence of new and a better understanding of risk factors, and discoveries in science that show promise for vaccine and novel future treatments. However, many of the principles of the HEDS study remain rightly entrenched in clinical practice. In this article, the HEDS study is revisited 20 years on through the lens of published literature, to determine current best practise and look towards the future.

Systemic diseases and the cornea

There is a number of systemic diseases affecting the cornea. These include endocrine disorders (diabetes, Graves' disease, Addison's disease, hyperparathyroidism), infections with viruses (SARS-CoV-2, herpes simplex, varicella zoster, HTLV-1, Epstein-Barr virus) and bacteria (tuberculosis, syphilis and Pseudomonas aeruginosa), autoimmune and inflammatory diseases (rheumatoid arthritis, Sjögren's syndrome, lupus erythematosus, gout, atopic and vernal keratoconjunctivitis, multiple sclerosis, granulomatosis with polyangiitis, sarcoidosis, Cogan's syndrome, immunobullous diseases), corneal deposit disorders (Wilson's disease, cystinosis, Fabry disease, Meretoja's syndrome, mucopolysaccharidosis, hyperlipoproteinemia), and genetic disorders (aniridia, Ehlers-Danlos syndromes, Marfan syndrome). Corneal manifestations often provide an insight to underlying systemic diseases and can act as the first indicator of an undiagnosed systemic condition. Routine eye exams can bring attention to potentially life-threatening illnesses. In this review, we provide a fairly detailed overview of the pathologic changes in the cornea described in various systemic diseases and also discuss underlying molecular mechanisms, as well as current and emerging treatments.

Pathobiology and treatment of viral keratitis

Keratitis is one of the most prevalent ocular diseases manifested by partial or total loss of vision. Amongst infectious (viz., microbes including bacteria, fungi, amebae, and viruses) and non-infectious (viz., eye trauma, chemical exposure, and ultraviolet exposure, contact lens) risk factors, viral keratitis has been demonstrated as one of the leading causes of corneal opacity. While many viruses have been shown to cause keratitis (such as rhabdoviruses, coxsackieviruses, etc.), herpesviruses are the predominant etiologic agent of viral keratitis. This chapter will summarize current knowledge on the prevalence, diagnosis, and pathobiology of viral keratitis. Virus-mediated immunomodulation of host innate and adaptive immune components is critical for viral persistence, and dysfunctional immune responses may cause destruction of ocular tissues leading to keratitis. Immunosuppressed or immunocompromised individuals may display recurring disease with pronounced severity. Early diagnosis of viral keratitis is beneficial for disease management and response to treatment. Finally, we have discussed current and emerging therapies to treat viral keratitis.

SARS-CoV-2 Infection (COVID-19) and Herpes Simplex Virus-1 Conjunctivitis: Concurrent Viral Infections or a Cause-Effect Result?

The pulmonary effects of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the virus that causes coronavirus disease (COVID-19), are well documented; however, more evidence is needed to understand its effect on multiple organ systems. We present the case of a 69-year-old male with dyspnea for two weeks and bilateral conjunctivitis who tested positive for SARS-CoV-2. He was found to be hypoxic, requiring supplemental oxygen. On hospital day two, he complained of worsening left eye pain with the development of a left lower eyelid ulcer. He underwent a CT of facial bones, which showed findings consistent with pre-septal cellulitis and abscess. Samples from bilateral conjunctival secretions and left lower eyelid ulcer tested positive for herpes simplex virus-1 (HSV-1), and negative for SARS-CoV-2. He received supportive care, antibiotics, and famciclovir with almost complete resolution of his ocular complaints. This case illustrates an atypical COVID-19 presentation and raises concern as to how this virus modulates the immune system, allowing for concurrent viral infections.

Corneal Graft Success Rates in HSV Keratitis: A Systematic Review

Herpes Simplex Virus (HSV) has worldwide prevalence. The primary objective of this systematic review was to compare penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK) regarding the efficacy and complications of the treatment of corneal scarring caused by herpes simplex keratitis. Out of the 469 articles identified during the combined search of the literature based on the PubMed and Cochrane libraries, 10 retrospective and 2 prospective studies published from January 2010 to December 2019 were included. The study outcomes indicated that both surgical approaches resulted in a comparable improvement of visual acuity (VA). However, DALK demonstrated fewer complications in the majority of studies. Higher graft survival rates were associated with higher acyclovir (ACV) doses (above 800 mg/day), topical steroid and antibiotic drops. In conclusion, in terms of postoperative VA, both PK and DALK demonstrate comparable efficacy. However, DALK, which is applied in less severe HSK cases, is associated with fewer complications and better graft survival rates. High dosages of ACV, topical steroids and antibiotics contribute significantly to improved postoperative outcomes.

Corneal Refractive Surgery in Patients with a History of Herpes Simplex Keratitis: A Narrative Review

The incidence of herpes simplex keratitis (HSK) in patients following corneal refractive surgery is higher than in the general population, and several case reports of ocular morbidity in HSK infection following corneal refractive surgery have been published. HSK is listed by the American Academy of Ophthalmology as a relative contraindication to corneal refractive surgery, although specifics have not been further elucidated. This review summarizes the current literature regarding reactivation of HSK following corneal refractive surgery and provides a guideline for considering corneal refractive surgery in a patient with a previous history of HSK. Based on the current literature, we recommend that corneal refractive surgery is appropriate for patients with a history of HSK without multiple recurrences who have had no evidence of disease for at least one year. In addition to a thorough history and physical examination, we also recommend these patients begin 400 mg twice daily of oral acyclovir or valacyclovir 500 mg once daily for two weeks prior to surgery and continue this regimen for at least two weeks postoperatively or while on topical steroids.

[Ocular manifestations of viral diseases]

Les infections virales peuvent toucher l’ensemble des tuniques oculaires et mettre en jeu la fonction visuelle à plus ou moins courte terme. Les kératites et kérato-uvéites liées au virus HSV-1 sont les atteintes les plus fréquentes. Les récurrences entraînent une opacification cornéenne irréversible qui en fait la première cause de cécité d’origine infectieuse dans les pays occidentaux, et justifient un traitement antiviral préventif au long cours. Le zona ophtalmique (10 à 20 % des zonas), peut s’accompagner d’atteintes oculaires sévères (kératites, kérato-uvéites), dont 30 % deviennent chroniques/récurrentes, et de douleurs post-zostériennes, redoutables dans le territoire trigéminé. Les rétinites nécrosantes liées aux herpesvirus (HSV, VZV, CMV), sont rares mais constituent des urgences fonctionnelles absolues nécessitant un traitement antiviral par voie intraveineuse et intravitréenne. Les conjonctivites à adénovirus constituent la première cause de conjonctivite infectieuse. Le plus souvent bénignes, elles sont extrêmement contagieuses et peuvent se compliquer de lésions cornéennes invalidantes persistant plusieurs mois, voire années. Certaines arboviroses s’accompagnent de manifestations oculaires inflammatoires. Dans le cas du Zika, les infections congénitales peuvent se compliquer d’atrophie maculaire et/ou optique. Les conjonctivites sont très fréquentes à la phase aiguë de la maladie à virus Ebola, dont 15 % des survivants présentent des atteintes inflammatoires chroniques sévères liées à la persistance du virus dans les tissus uvéaux. Enfin, dans le cadre de la COVID-19, les conjonctivites ne sont pas très fréquentes mais peuvent être inaugurales, voire au premier plan et sont associées à une excrétion virale lacrymale qui doit faire prendre toutes les précautions.

[Research progress on etiologic diagnosis of ocular viral diseases]

A large number of viruses have been found to be associated with ocular diseases, including human adenovirus, human herpesvirus (HHV), human T lymphotropic virus type-1 (HTLV-1), and newly emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This group of diseases is prone to be misdiagnosed or missed diagnosis, resulting in serious tissue and visual damage. Etiological diagnosis is a powerful auxiliary mean to diagnose the ocular diseases associated with human adenovirus, herpes simplex virus 1 and varicella-zoster virus, and it provides the leading diagnosis evidence of infections with herpes simplex virus 2, Epstein-Barr virus, cytomegalovirus, HHV-6/7, HHV-8, HTLV-1 and SARS-CoV-2. Virus isolation, immunoassay and genetic diagnosis are usually used for etiologic diagnosis. For genetic diagnosis, the PCR technique is the most important approach because of its advantages of rapid detection, convenient operation, high sensitivity and high specificity.

Update on Herpes simplex keratitis management

Herpes simplex keratitis (HSK) is a common, potentially blinding condition characterised by recurrent infections of the cornea, seen by both general ophthalmologists and corneal specialists. Successful treatment of recurrences reduces disease duration, prevents progressive corneal scaring leading to vision loss and reduces risk of further recurrences. In this review we discuss the relative advantages of the diagnostic laboratory investigations including polymerase chain reaction, viral culture and fluorescence-based immunohistochemistry. We review treatment strategies in selected aspects of HSK and discuss the management options in cases not responding to treatment.

Restoring Herpesvirus Entry Mediator (HVEM) Immune Function in HVEM-/- Mice Rescues Herpes Simplex Virus 1 Latency and Reactivation Independently of Binding to Glycoprotein D

The immune modulatory protein herpes virus entry mediator (HVEM) is one of several cellular receptors used by herpes simplex virus 1 (HSV-1) for cell entry. HVEM binds to HSV-1 glycoprotein D (gD) but is not necessary for HSV-1 replication in vitro or in vivo Previously, we showed that although HSV-1 replication was similar in wild-type (WT) control and HVEM-/- mice, HSV-1 does not establish latency or reactivate effectively in mice lacking HVEM, suggesting that HVEM is important for these functions. It is not known whether HVEM immunomodulatory functions contribute to latency and reactivation or whether its binding to gD is necessary. We used HVEM-/- mice to establish three transgenic mouse lines that express either human WT HVEM or human or mouse HVEM with a point mutation that ablates its ability to bind to gD. Here, we show that HVEM immune function, not its ability to bind gD, is required for WT levels of latency and reactivation. We further show that HVEM binding to gD does not affect expression of the HVEM ligands BTLA, CD160, or LIGHT. Interestingly, our results suggest that binding of HVEM to gD may contribute to efficient upregulation of CD8α but not PD1, TIM-3, CTLA4, or interleukin 2 (IL-2). Together, our results establish that HVEM immune function, not binding to gD, mediates establishment of latency and reactivation.IMPORTANCE HSV-1 is a common cause of ocular infections worldwide and a significant cause of preventable blindness. Corneal scarring and blindness are consequences of the immune response induced by repeated reactivation events. Therefore, HSV-1 therapeutic approaches should focus on preventing latency and reactivation. Our data suggest that the immune function of HVEM plays an important role in the HSV-1 latency and reactivation cycle that is independent of HVEM binding to gD.

Ex vivo model of herpes simplex virus type I dendritic and geographic keratitis using a corneal active storage machine

BACKGROUND

Herpetic keratitis (HK) models using whole human corneas are essential for studying virus-host relationships, because of high species specificity and the role of interactions between corneal cell populations that cell culture cannot reproduce. Nevertheless, the two current corneal storage methods (hypothermia and organ culture (OC)) do not preserve corneas in good physiological condition, as they are characterized by epithelial abrasion, stromal oedema, and excessive endothelial mortality.

METHODS

To rehabilitate human corneas intended for scientific use, we used an active storage machine (ASM) that restores two physiological parameters that are essential for corneal homeostasis: intraocular pressure and storage medium renewal (21mmHg and 2.6 μL/min, respectively). ASM storage regenerates a normal multilayer epithelium in 2 weeks. We infected six pairs of corneas unsuitable for graft by inoculating the epithelium with herpes simplex virus type 1 (HSV-1), and compared each ASM-stored cornea with the other cornea stored in the same medium using the conventional OC method.

RESULTS

Only corneas in the ASM developed a dendritic (n = 3) or geographic (n = 2) epithelial ulcer reproducing typical HSV-1-induced clinical lesions. Corneas in OC showed only extensive desquamations. None of the uninfected controls showed epithelial damage. Histology, immunohistochemistry, transmission electron microscopy and polymerase chain reaction on corneal tissue confirmed infection in all cases (excluding negative controls).

CONCLUSIONS

The ASM provides an innovative ex vivo model of HK in whole human cornea that reproduces typical epithelial lesions.

Role of TH17 Responses in Increasing Herpetic Keratitis in the Eyes of Mice Infected with HSV-1

Purpose

T_H17 cells play an important role in host defense and autoimmunity yet very little is known about the role of IL17 in herpes simplex virus (HSV)-1 infectivity. To better understand the relationship between IL17 and HSV-1 infection, we assessed the relative impact of IL17A-deficiency and deficiency of its receptors on HSV-1 responses in vivo.

Methods

We generated IL17RA^−/− and IL17RA^−/−RC^−/− mice in-house and infected them along with IL17A^−/− and IL17RC^−/− mice in the eyes with 2 × 10⁵ PFU/eye of wild type (WT) HSV-1 strain McKrae. WT C57BL/6 mice were used as control. Virus replication in the eye, survival, corneal scarring (CS), angiogenesis, levels of latency-reactivation, and levels of CD8 and exhaustion markers (PD1, TIM3, LAG3, CTLA4, CD244, and CD39) in the trigeminal ganglia (TG) of infected mice were determined on day 28 postinfection.

Results

No significant differences in virus replication in the eye, survival, latency, reactivation, and exhaustion markers were detected among IL17A^−/−, IL17RA^−/−, IL17RC^−/−, IL17RA^−/−RC^−/−, and WT mice. However, mice lacking IL17 had significantly less CS and angiogenesis than WT mice. In addition, angiogenesis levels in the absence of IL17RC and irrespective of the absence of IL17RA were significantly less than in IL17A- or IL17RA-deficient mice.

Conclusions

Our results suggest that the absence of IL17 protects against HSV-1-induced eye disease, but has no role in protecting against virus replication, latency, or reactivation. In addition, our data provide rationale for blocking IL17RC function rather than IL17A or IL17RA function as a key driver of HSV-1-induced eye disease.

Blockade of IL-27 signaling ameliorates herpes stromal keratitis with upregulated CD4+ Foxp3+ regulatory T cells influx in mice

Purpose:

The purpose of this study was to investigate the production of IL-27 p28 and EBI3 in the ocular inflammatory sites, and the role of IL-27 signaling in a model of HSV-1 induced herpetic stromal keratitis (HSK).

Methods:

The BALB/c mice were injected intraperitoneally (24 h before infection) with anti-IL-27 antibody or IgG antibody as control, infected with HSV-1 via corneal scarification, and then injected intraperitoneally with anti-IL-27 antibody or IgG antibody at 1, 3, and 5 days postinfection. Slit lamp and histopathology were used to assess disease outcome. The levels of IL-27 p28 and EBI3 in corneas were determined by western blotting and immunofluorescence. Furthermore, viral titers were determined, and immune cell infiltrates were collected and analyzed by flow cytometry.

Results:

We found that the levels of IL-27 p28 and EBI3 in corneas were elevated significantly at the peak of HSK, and both of them were expressed simultaneously in the epithelium, stroma, and endothelium of corneas. In the group of anti-IL-27 treatment, the severity of the corneal lesion and CD4⁺ T cells infiltration were significantly decreased, and the percentage of CD4⁺ Foxp3⁺ Tregs was upregulated markedly in the spleen, DLNs and cornea of HSK mice compared to IgG treatment.

Conclusion:

These results provided evidence that IL-27 as a pathogenic pro-inflammatory cytokine controlled CD4⁺ Foxp3⁺ Tregs production in HSK, which ultimately resulted in promoting the progression of HSK and poor prognosis.

Concomitant herpes simplex keratitis and autoimmune-associated ulcerative keratitis in rheumatoid arthritis patients

Purpose

To describe four cases of concomitant herpes simplex keratitis (HSK) and autoimmune-associated ulcerative keratitis (UK) in patients with rheumatoid arthritis (RA).

Observations

All patients developed HSK and UK while undergoing treatment for RA. The average age of onset for RA, UK and HSK was 49.3, 69.5 and 70.5 years, respectively. UK preceded HSK in three cases and followed HSK in one case. Two patients had bilateral UK and two had unilateral UK. HSK was unilateral in all cases. All the cases had been treated with immunosuppressive agents including steroid, methotrexate, calcineurin inhibitors, etanercept and tocilizumab at the onset of HSK. Every patient was treated for HSK with topical acyclovir ointment combined with oral valacyclovir. The final visual outcome was extremely poor despite intensive therapy.

Conclusions and Importance

These cases raise the possibility that RA patients have an increased risk of HSK, and that HSK may tend to be severe in these patients because of their immunocompromised condition. Furthermore, the complication of HSK and UK in RA patients is difficult to treat because of the atypical clinical manifestation. Thus, the emergence of corneal ulcer, especially in patients with a long clinical history of RA, calls for careful follow-up.

Concomitant herpetic keratitis and acute retinal necrosis: clinical features and outcomes

BACKGROUND/OBJECTIVES

The aim of this study was to identify risk factors, prognosis, and management in patients with concomitant herpetic keratitis and acute retinal necrosis (ARN).

SUBJECTS/METHODS

In this retrospective observational series, ARN patients in the Greater Vancouver area from 2004 to 2018 were identified through key words, billing codes, and dispensing data from medical records of affiliate researchers and the pharmacy at Vancouver General Hospital.

RESULTS

Twenty-eight patients were diagnosed with ARN during this period. Five of those were also diagnosed with herpetic keratitis. Thus, the incidence of combined keratitis and ARN was 18% of patients with ARN. The two diseases occurred concomitantly in four out of five patients. Mean age at diagnosis was 55 ± 17 years. Of the five patients with both corneal and retinal involvement, three patients were immunocompromised and three had a history of herpetic diseases. Three developed disciform keratitis and two developed stromal immune keratitis. Clinical management and outcomes of these patients did not differ from patients with ARN alone, except for a lower rate of retinal detachment (p = 0.006) and a higher proportion with visual acuity ≥ 20/200 (p = 0.01).

CONCLUSIONS

Keratitis may complicate the clinical picture of one out of five to six patients with ARN. Comprehensive ophthalmic examination, including careful anterior segment exams in patients with ARN and sequential dilated fundus exams in patients with herpetic keratitis, should always be conducted to identify cases of concomitant disease.

Herpes Simplex Virus Keratitis

Herpes simplex virus (HSV) is a highly prevalent infection in the United States. One complication of HSV is HSV keratitis, an ocular HSV infection thought to be the leading cause of corneal blindness in the United States. Home care clinicians with knowledge of the signs and symptoms of HSV and HSV keratitis can aid in early detection and treatment of this potentially serious infection. This article discusses signs and symptoms of HSV keratitis, preventive measures, and treatment.

Necrotic Herpes Simplex Virus Infection of the Nose and Orbit

This is the first reported case of necrotizing nasal and sinus herpes infection with orbital involvement. A 94-year-old male with a past medical history of hypertension, congestive heart failure, and chronic kidney disease presented with necrotic nasal cellulitis and a red left eye with blurry vision. Onset was 2 weeks prior with an upper lip fever blister. He was admitted to medicine and started on antimicrobials. Maxillofacial computed tomography scan revealed pansinusitis with involvement of bilateral medial orbital walls. Initial nasal biopsy was negative. Repeat biopsy was positive for herpes simplex virus 1. His nose was debrided with full-thickness skin grafting. While there are reports of necrotizing herpes simplex, none were to the extent of our patient nor raised suspicion for invasive fungal sinusitis. Differentiating is important as this patient made a full recovery in comparison to patients with mucormycosis where mortality is often as high as 80%.

Herpes Simplex Virus 1 Replication, Ocular Disease, and Reactivations from Latency Are Restricted Unilaterally after Inoculation of Virus into the Lip

Ocular herpes simplex keratitis (HSK) is a consequence of viral reactivations from trigeminal ganglia (TG) and occurs almost exclusively in the same eye in humans. In our murine oro-ocular (OO) model, herpes simplex virus 1 (HSV-1) inoculation in one side of the lip propagates virus to infect the ipsilateral TG. Replication here allows infection of the brainstem and infection of the contralateral TG. Interestingly, HSK was observed in our OO model only from the eye ipsilateral to the site of lip infection. Thus, unilateral restriction of HSV-1 may be due to differential kinetics of virus arrival in the ipsilateral versus contralateral TG. We inoculated mice with HSV-1 reporter viruses and then superinfected them to monitor changes in acute- and latent-phase gene expression in TG after superinfection compared to the control (single inoculation). Delaying superinfection by 4 days after initial right lip inoculation elicited failed superinfecting-virus gene expression and eliminated clinical signs of disease. Initial inoculation with thymidine kinase-deficient HSV-1 (TK_del) completely abolished reactivation of wild-type (WT) superinfecting virus from TG during the latent stage. In light of these seemingly failed infections, viral genome was detected in both TG. Our data demonstrate that inoculation of HSV-1 in the lip propagates virus to both TG, but with delay in reaching the TG contralateral to the side of lip infection. This delay is responsible for restricting viral replication to the ipsilateral TG, which abrogates ocular disease and viral reactivations from the contralateral side. These observations may help to understand why HSK is observed unilaterally in humans, and they provide insight into vaccine strategies to protect against HSK.IMPORTANCE Herpetic keratitis (HK) is the leading cause of blindness by an infectious agent in the developed world. This disease can occur after reactivation of herpes simplex virus 1 in the trigeminal ganglia, leading to dissemination of virus to, and infection of, the cornea. A clinical paradox is evidenced by the bilateral presence of latent viral genomes in both trigeminal ganglia, while for any given patient the disease is unilateral with recurrences in a single eye. Our study links the kinetics of early infection to unilateral disease phenomenon and demonstrates protection against viral reactivation when kinetics are exploited. Our results have direct implications in the understanding of human disease pathogenesis and immunotherapeutic strategies for the treatment of HK and viral reactivations.

The Role of C21orf91 in Herpes Simplex Virus Keratitis

Background and Objectives: This paper aims to describe the single nucleotide polymorphisms (SNPs) of C21orf91 rs1062202 and rs10446073 in patients with herpetic keratitis by evaluating corneal sub-basal nerves, as well as the density of Langerhans cells (LC) and endothelium cells (EC) during the acute phase of the disease. Materials and Methods: A prospective clinical study included 260 subjects: 70 with herpetic eye disease, 101 with previous history of herpes labialis—but no history of herpetic eye disease—and 89 with no history of any herpes simplex virus (HSV) diseases. All subjects underwent a complete ophthalmological examination including in vivo laser scanning confocal microscopy (LSCM) of the central cornea. C21orf91 rs1062202 and rs10446073 were genotyped using the real-time polymerase chain reaction (PCR) method with the Rotor-Gene Q real-time PCR quantification system. SNPs were determined using TaqMan genotyping assay, according to the manufacturer’s manual. Results: The C21orf91 rs10446073 genotype GT was more frequent in the HSV keratitis group, compared with healthy controls (20.0% vs. 7.9%), OR 2.929[1.11–7.716] (p < 0.05). The rs10446073 genotype TT was more frequent in healthy controls (12.4% vs. 1.4%), OR 22.0[2.344–260.48] (p < 0.05). The rs10446073 genotype GT increased the risk of EC density being less than 2551.5 cell/mm², OR 2.852[1.248–6.515] (p < 0.05). None of the SNPs and their genotypes influenced the LC density and corneal sub-basal nerve parameters (p > 0.05). Conclusions: Our study reports a new association between herpetic keratitis and human gene C21orf91, with the rs10446073 genotype GT being more common in herpetic keratitis patients and increasing the risk for the disease by a factor of 2.9.

Epidemiology and molecular diagnosis of acute conjunctivitis in patients attending Hamadan, west Iran ophthalmology clinics 2016-2017

BACKGROUND

Viruses are considered the most common cause of infectious conjunctivitis. PCR has been approved as the best standard method to diagnose viral conjunctivitis. This study was conducted to investigate epidemiological patterns of conjunctivitis in Hamadan, west Iran. In addition, the frequency of the most important cause of infectious conjunctivitis diagnosed by PCR and its seasonal variations and association with certain socioeconomic and health factors were studied.

METHODS

In this cross-sectional study, 125 patients with suspected viral conjunctivitis or keratoconjunctivitis in Hamadan, west Iran from July 2016 to June 2017 were examined for the presence of herpes simplex virus 1 (HSV1), HSV2, varicella-zoster virus (VZV), adenovirus. and Chlamydia trachomatis using multiplex real-time PCR.

RESULTS

Adenoviruses were the most prevalent pathogens (94.4%). HSV1 was found in two (1.6%) patients. HSV2, VZV, and C. trachomatis were not seen in any patients. There was no difference in acquisition of conjunctivitis between men and women. A total of 55 (44%) patients attended the clinics in summer.

CONCLUSION

This study demonstrated that adenoviruses were a much more common viral cause of conjunctivitis in the studied region compared to findings in other regions. In addition, the acquisition rate of eye infection is expected to decrease dramatically in this region through control of adenoviruses. Demographic variables ie, age, sex, and income level, were not significantly associated with acquisition of viral infection.

Corneal Sub-Basal Nerve Changes in Patients with Herpetic Keratitis During Acute Phase and after 6 Months

Background and objectives: The purpose of this study was to describe corneal sensitivity and the morphological changes of sub-basal corneal nerves using in vivo laser scanning confocal microscopy (LSCM) in herpes simplex virus (HSV) keratitis-affected eyes, and to compare with both contralateral eyes and with the eyes of patients with a previous history of herpes labialis but no history of herpetic eye disease, and with healthy patients with no history of any HSV diseases, during the acute phase of the disease and after six months. Materials and Methods: A prospective clinical study included 269 patients. All of them underwent a complete ophthalmological examination, Cochet-Bonnet aesthesiometry and LSCM within the central 5 mm of the cornea. After six months, all the patients with herpetic eye disease underwent the same examination. Serology tests of the serum to detect HSV 1/2 IgG and IgM were performed. Results: HSV-affected eyes compared with contralateral eyes, herpes labialis and healthy control group eyes demonstrated a significant decrease in corneal sensitivity, corneal nerve fibre density, corneal nerve branch density, corneal nerve fibre length and corneal nerve total branch density (p < 0.05). During follow up after six months, corneal sensitivity and sub-basal nerve parameters had increased but did not reach the parameters of contralateral eyes (p < 0.05). Previous herpes labialis did not influence corneal sensitivity and was not a risk factor for herpetic eye disease. Conclusions: Corneal sensitivity and sub-basal nerve changes in HSV-affected eyes revealed a significant decrease compared with contralateral eyes, and with the eyes of patients with a previous history of herpes labialis, and of healthy controls. Following six months, corneal sensitivity and sub-basal nerve parameters increased; however, they did not reach the parameters of contralateral eyes and the eyes of healthy controls. The best recovery of corneal sensitivity was seen in patients with epithelial keratitis. Herpes labialis was not a risk factor for herpetic eye disease.

Therapeutic Challenges and Prognosis of Descemet's Membrane Endothelial Keratoplasty in Herpes Simplex Eye Disease

PURPOSE

To describe the functional outcome, postoperative complications, and complication management of Descemet's membrane endothelial keratoplasty (DMEK) in corneal decompensation secondary to Herpes simplex eye disease (HED).

METHODS

This retrospective interventional case series included 17 eyes that received DMEK for endothelial decompensation secondary to HED. Complete ophthalmological examination, including corrected-distance visual acuity (CDVA), anterior segment slit-lamp, and optical coherence tomography assessment, were performed preoperatively and postoperatively at regular follow-up intervals. Visual outcome and complication rates were compared with those of 72 consecutive eyes that received DMEK for Fuchs endothelial corneal dystrophy (FECD) and pseudophakic bullous keratopathy (PBK) during the same period.

RESULTS

Mean follow-up time was 11.1 ± 5.9 months (range 6-27). CDVA improved from 1.16 ± 0.46 logMAR to 0.62 ± 0.44 logMAR (P = 0.001). Corneal pachymetry significantly decreased from 695 ± 53 μm at day 1 to 569 ± 88 μm at 2 months (P < 0.001). Postoperative complications occurred in 12 eyes, including primary graft failure (12%), endotheliitis (29%), corneal ulcers (35%), and cystoid macular edema (18%). Most complications occurred shortly after surgery, with a median delay of 2.5 months. In comparison, the complication rates for DMEK in FECD and PBK were significantly lower (no graft failure, P = 0.005; no endotheliitis, P < 0.001; no corneal ulcers, P < 0.001 and 3% cystoid macular edema, P = 0.046).

CONCLUSIONS

DMEK surgery significantly improved CDVA in patients with endothelial decompensation due to HED. The rate of postoperative complications was higher than for FECD and PBK. Close follow-up is mandatory and the rate of postoperative inflammatory events suggests that patients should be kept on high doses of oral valacyclovir.

The Role of T Cells in Herpes Stromal Keratitis

The blinding inflammatory lesion stromal keratitis (SK), which occurs in some patients in response to ocular herpes simplex virus (HSV) infection, represents mainly an immune cell mediated inflammatory response to the virus infection. The principal orchestrators of the immunopathological lesions are T cells although additional events participate that include the extent of recruitment of non-lymphoid cells, the extent of neoangiogenesis, and the extent of damage to nerve function. This review focuses on evidence that the balance of the functional subsets of T cells has a major impact on lesion severity and duration. Accordingly, if proinflammatory Th1 and Th17 CD4 T cells, and perhaps in some cases CD8 T cells, predominate lesions occur earlier and are more severe. Lesions are diminished when cells with regulatory function predominate. Moreover, when regulatory cells acquire the property to produce Amphiregulin this may facilitate lesion resolution. An objective to controlling lesions is to learn how to manipulate the balance of T cells to favor the representation and function of regulatory T cells and their products over proinflammatory cells. In this review we emphasize how exploiting the differential metabolic requirements of immune cells could be a valuable approach to control SK.

Herpes Simplex Virus 1 ICP22 Suppresses CD80 Expression by Murine Dendritic Cells

Herpes simplex virus type 1 (HSV-1) has the ability to delay its clearance from the eye during ocular infection. Here, we show that ocular infection of mice with HSV-1 suppressed expression of the costimulatory molecule CD80 but not CD86 in the cornea. The presence of neutralizing anti-HSV-1 antibodies did not alleviate this suppression. At the cellular level, HSV-1 consistently downregulated the expression of CD80 by dendritic cells (DCs) but not by other antigen-presenting cells. Furthermore, flow cytometric analysis of HSV-1-infected corneal cells during a 7-day period reduced CD80 expression in DCs but not in B cells, macrophages, or monocytes. This suppression was associated with the presence of virus. Similar results were obtained using infected or transfected spleen cells or bone marrow-derived DCs. A combination of roscovitine treatment, transfection with immediate early genes (IE), and infection with a recombinant HSV-1 lacking the ICP22 gene shows the importance of ICP22 in downregulation of the CD80 promoter but not the CD86 promoter in vitro and in vivo At the mechanistic level, we show that the HSV-1 immediate early gene ICP22 binds the CD80 promoter and that this interaction is required for HSV-1-mediated suppression of CD80 expression. Conversely, forced expression of CD80 by ocular infection of mice with a recombinant HSV-1 exacerbated corneal scarring in infected mice. Taken together, these studies identify ICP22-mediated suppression of CD80 expression in dendritic cells as central to delayed clearance of the virus and limitation of the cytopathological response to primary infection in the eye.IMPORTANCE HSV-1-induced eye disease is a major public health problem. Eye disease is associated closely with immune responses to the virus and is exacerbated by delayed clearance of the primary infection. The immune system relies on antigen-presenting cells of the innate immune system to activate the T cell response. We found that HSV-1 utilizes a robust and finely targeted mechanism of local immune evasion. It downregulates the expression of the costimulatory molecule CD80 but not CD86 on resident dendritic cells irrespective of the presence of anti-HSV-1 antibodies. The effect is mediated by direct binding of HSV-1 ICP22, the product of an immediate early gene of HSV-1, to the promoter of CD80. This immune evasion mechanism dampens the host immune response and, thus, reduces eye disease in ocularly infected mice. Therefore, ICP22 may be a novel inhibitor of CD80 that could be used to modulate the immune response.

Pathogenesis of herpes simplex keratitis: The host cell response and ocular surface sequelae to infection and inflammation

Herpes simplex virus type 1 (HSV) keratitis is a leading cause of infectious blindness. Clinical disease occurs variably throughout the cornea from epithelium to endothelium and recurrent HSV stromal keratitis is associated with corneal scarring and neovascularization. HSV keratitis can be associated with ocular pain and subsequent neutrophic keratopathy. Host cell interactions with HSV trigger an inflammatory cascade responsible not only for clearance of virus but also for progressive corneal opacification due to inflammatory cell infiltrate, angiogenesis, and corneal nerve loss. Current antiviral therapies target viral replication to decrease disease duration, severity and recurrence, but there are limitations to these agents. Therapies directed towards viral entry into cells, protein synthesis, inflammatory cytokines and vascular endothelial growth factor pathways in animal models represent promising new approaches to the treatment of recurrent HSV keratitis.

R430: A potent inhibitor of DNA and RNA viruses

Acyclovir (ACV) is an effective antiviral agent for treating lytic Herpes Simplex virus, type 1 (HSV-1) infections, and it has dramatically reduced the mortality rate of herpes simplex encephalitis. However, HSV-1 resistance to ACV and its derivatives is being increasingly documented, particularly among immunocompromised individuals. The burgeoning drug resistance compels the search for a new generation of more efficacious anti-herpetic drugs. We have previously shown that trans-dihydrolycoricidine (R430), a lycorane-type alkaloid derivative, effectively inhibits HSV-1 infections in cultured cells. We now report that R430 also inhibits ACV-resistant HSV-1 strains, accompanied by global inhibition of viral gene transcription and enrichment of H3K27me3 methylation on viral gene promoters. Furthermore, we demonstrate that R430 prevents HSV-1 reactivation from latency in an ex vivo rodent model. Finally, among a panel of DNA viruses and RNA viruses, R430 inhibited Zika virus with high therapeutic index. Its therapeutic index is comparable to standard antiviral drugs, though it has greater toxicity in non-neuronal cells than in neuronal cells. Synthesis of additional derivatives could enable more efficacious antivirals and the identification of active pharmacophores.

A Review of the Cytokine IL-17 in Ocular Surface and Corneal Disease

Aim: To investigate the role of interleukin-17 in ocular surface and corneal disease. Ocular surface and corneal disease is a leading cause of blindness and is an ongoing challenge for the public health sector to implement effective therapies. The majority of cells in corneal lesions are derived primarily from neutrophils that induce inflammatory events that lead to tissue damage. One of the key pro-inflammatory cytokines is IL-17, and it has been investigated in order to facilitate the understanding of the pathogenesis of ocular surface lesion development. Method: A review of the literature was performed through a systematic approach. Results: IL-17 has been shown to exacerbate dry eye disease, viral and bacterial keratitis lesion severity, although it was found to be protective for Acanthamoeba. Antibodies developed to neutralize IL-17 have shown some promise in reducing the severity of some diseases. Conclusion: IL-17 plays a role in the pathogenesis of ocular surface and corneal disease and targeting this cytokine may provide a useful treatment option in the future.

Management of herpes simplex virus epithelial keratitis

PURPOSE OF REVIEW

To review recent advancements in the management of herpes simplex virus (HSV) epithelial keratitis.

RECENT FINDINGS

Trifluridine eye drop, acyclovir (ACV) ointment, ganciclovir gel, and oral ACV are still the main therapeutic agents. Cryopreserved amniotic membrane has been recently used as an adjuvant treatment. Resistance to ACV has become a concerning issue. The animal models of HSV vaccine are able to reduce HSV keratitis. New antivirals are under development.

SUMMARY

Current cases of HSV epithelial keratitis are manageable with available medications, but new advancements are required to decrease disease burden in the future. HSV vaccine can be revolutionary.

An M2 Rather than a TH2 Response Contributes to Better Protection against Latency Reactivation following Ocular Infection of Naive Mice with a Recombinant Herpes Simplex Virus 1 Expressing Murine Interleukin-4

We found previously that altering macrophage polarization toward M2 responses by injection of colony-stimulating factor 1 (CSF-1) was more effective in reducing both primary and latent infections in mice ocularly infected with herpes simplex virus 1 (HSV-1) than M1 polarization by gamma interferon (IFN-γ) injection. Cytokines can coordinately regulate macrophage and T helper (T_H) responses, with interleukin-4 (IL-4) inducing type 2 T_H (T_H2) as well as M2 responses and IFN-γ inducing T_H1 as well as M1 responses. We have now differentiated the contributions of these immune compartments to protection against latency reactivation and corneal scarring by comparing the effects of infection with recombinant HSV-1 in which the latency-associated transcript (LAT) gene was replaced with either the IL-4 (HSV-IL-4) or IFN-γ (HSV-IFN-γ) gene using infection with the parental (LAT-negative) virus as a control. Analysis of peritoneal macrophages in vitro established that the replacement of LAT with the IL-4 or IFN-γ gene did not affect virus infectivity and promoted polarization appropriately. Protection against corneal scarring was significantly higher in mice ocularly infected with HSV-IL-4 than in those infected with HSV-IFN-γ or parental virus. Levels of primary virus replication in the eyes and trigeminal ganglia (TG) were similar in the three groups of mice, but the numbers of gC⁺ cells were lower on day 5 postinfection in the eyes of HSV-IL-4-infected mice than in those infected with HSV-IFN-γ or parental virus. Latency and explant reactivation were lower in both HSV-IL-4- and HSV-IFN-γ-infected mice than in those infected with parental virus, with the lowest level of latency being associated with HSV-IL-4 infection. Higher latency correlated with higher levels of CD8, PD-1, and IFN-γ mRNA, while reduced latency and T-cell exhaustion correlated with lower gC⁺ expression in the TG. Depletion of macrophages increased the levels of latency in all ocularly infected mice compared with their undepleted counterparts, with macrophage depletion increasing latency in the HSV-IL-4 group greater than 3,000-fold. Our results suggest that shifting the innate macrophage immune responses toward M2, rather than M1, responses in HSV-1 infection would improve protection against establishment of latency, reactivation, and eye disease.IMPORTANCE Ocular HSV-1 infections are among the most frequent serious viral eye infections in the United States and a major cause of virus-induced blindness. As establishment of a latent infection in the trigeminal ganglia results in recurrent infection and is associated with corneal scarring, prevention of latency reactivation is a major therapeutic goal. It is well established that absence of latency-associated transcripts (LATs) reduces latency reactivation. Here we demonstrate that recombinant HSV-1 expressing IL-4 (an inducer of T_H2/M2 responses) or IFN-γ (an inducer of T_H1/M1 responses) in place of LAT further reduced latency, with HSV-IL-4 showing the highest overall protective efficacy. In naive mice, this higher protective efficacy was mediated by innate rather than adaptive immune responses. Although both M1 and M2 macrophage responses were protective, shifting macrophages toward an M2 response through expression of IL-4 was more effective in curtailing ocular HSV-1 latency reactivation.

Corneal Higher-order Aberrations and Visual Improvement Following Corneal Transplantation in Treating Herpes Simplex Keratitis

PURPOSE

To examine corneal higher-order aberrations (HOAs) and visual improvement following corneal transplantation in treating corneal scar caused by herpes simplex keratitis (HSK).

DESIGN

Retrospective consecutive case series.

METHODS

This study included a total of 52 eyes: 18 eyes of normal subjects, and 34 eyes of consecutive patients with corneal scar owing to HSK who underwent penetrating keratoplasty (PKP, 17 eyes) or deep anterior lamellar keratoplasty (DALK, 17 eyes). HOAs of the anterior, posterior surfaces and the total cornea were analyzed by anterior segment optical coherence tomography. The correlations between corneal HOAs and visual improvement were also analyzed.

RESULTS

Mean logarithm of the minimal angle of resolution (logMAR) visual acuity significantly improved from 1.40 ± 0.70 to 0.46 ± 0.45 after corneal transplantation (P < .0001). Mean corneal HOAs of the anterior surface significantly decreased after corneal transplantation (PKP: from 1.16 ± 0.59 μm to 0.58 ± 0.35 μm, P = .035, DALK: from 0.94 ± 0.57 μm to 0.37 ± 0.18 μm, P = .004). Visual acuity following corneal transplantation was correlated with the corneal HOAs at 12 months (r = 0.53, P = .01). Visual improvement at 3, 6, and 12 months was positively correlated with preoperative HOAs of the total cornea and posterior surface (all P < .01).

CONCLUSIONS

Preoperative corneal HOAs were associated with the visual improvement in treating corneal scar caused by HSK. Thus, the preoperative assessment of corneal HOAs, especially of the posterior surface, is important in the decision to perform corneal transplantation in eyes with HSK.

New Paradigms for the Study of Ocular Alphaherpesvirus Infections: Insights into the Use of Non-Traditional Host Model Systems

Ocular herpesviruses, most notably human alphaherpesvirus 1 (HSV-1), canid alphaherpesvirus 1 (CHV-1) and felid alphaherpesvirus 1 (FHV-1), infect and cause severe disease that may lead to blindness. CHV-1 and FHV-1 have a pathogenesis and induce clinical disease in their hosts that is similar to HSV-1 ocular infections in humans, suggesting that infection of dogs and cats with CHV-1 and FHV-1, respectively, can be used as a comparative natural host model of herpesvirus-induced ocular disease. In this review, we discuss both strengths and limitations of the various available model systems to study ocular herpesvirus infection, with a focus on the use of these non-traditional virus-natural host models. Recent work has demonstrated the robustness and reproducibility of experimental ocular herpesvirus infections in dogs and cats, and, therefore, these non-traditional models can provide additional insights into the pathogenesis of ocular herpesvirus infections.

Clinical Features and Prognosis of Herpetic Anterior Uveitis

Objective:

To evaluate clinical features, complications, visual outcomes and treatment modalities in patients clinically diagnosed with herpetic anterior uveitis (AU).

Materials and Methods:

We retrospectively reviewed the medical records of 67 patients seen at the Umraniye Training and Research Hospital, Ophthalmology Clinic, Uveitis and Cornea Department from January 2009 to June 2013.

Results:

Thirty-seven patients (55.2%) were female and 30 (44.7%) patients were male. The average follow-up period was 12.9 ± 10.6 months (range: 1-45 months). The most common ocular findings were granulomatous keratic precipitates (KPs) (82.2%), corneal involvement (62.6%), iris atrophy (41.7%) and transient elevated intraocular pressure (IOP) (40.2%). Recurrences were observed in 46.2% of the eyes and the median recurrence rate was 1.0 during the follow-up period. Topical steroids and oral antiviral (acyclovir) therapy were applied to all patients during active episodes. Long-term oral acyclovir was used in 29.8% of the patients. Recurrence rates were significantly lower in patients who used oral acyclovir for more than 6 months, whereas complications rates and final visual acuity did not show any difference between groups. Final visual acuity was better than 20/40 in 61.1% of eyes, and visual impairment was due to corneal scarring or cataract formation.

Conclusion:

Herpetic AU can present with or without corneal involvement. Granulomatous KPs, iris atrophy and elevated IOP are important clinical findings for the diagnosis of cases without corneal involvement. Long-term oral acyclovir treatment (more than 6 months) and is important to decrease recurrence rates and possible complications. Visual prognosis is favorable in cases without corneal scarring.

Challenges of corneal infections

INTRODUCTION

Ocular infections remain an important cause of blindness worldwide and represent a challenging public health concern. In this regard, microbial keratitis due to fungal, bacterial, or viral infection can result in significant vision loss secondary to corneal scarring or surface irregularity. Left untreated corneal perforation and endophthalmitis can result, leading to loss of the eye. Rigorously studied animal models of disease pathogenesis have provided novel information that suggests new modes of treatment that may be efficacious clinically and emerging clinical data is supportive of some of these discoveries.

AREAS COVERED

This review focuses on advances in our understanding of disease pathogenesis in animal models and clinical studies and how these relate to improved clinical treatment. We also discuss a novel approach to treatment of microbial keratitis due to infection with these bacterial pathogens using PACK-CXL and recommend increased basic and clinical studies to address and refine the efficacy of this procedure.

EXPERT COMMENTARY

Because resistance to antibiotics has developed over time to these bacterial pathogens, caution must be exercised in treatment. Attractive novel modes of treatment that hold new promise for further investigation include lipid based therapy, as well as use of small molecules that bind deleterious specific host responsive molecules and use of microRNA based therapies.

Changes in Corneal Innervation after HSV-1 Latency Established with Different Reactivation Phenotypes

PURPOSE OF THE STUDY

We used a rabbit model infected with high phenotypic reactivators (HPRs) as well as recombinant HSV-1 (herpes simplex virus 1) with deletions to study their effect on corneal innervations after latency was established.

MATERIALS AND METHODS

Corneas from noninfected New Zealand white rabbits were used to obtain the entire map of corneal innervation. Others were inoculated with the HSV-1 strains McKrae, 17Syn+, or recombinant mutants with glycoprotein K (gK) deletion, or with infected early protein 0 (ICP0) deletion. The animals were euthanized at 124 to 125 days postinfection and the corneas were immunostained with a mouse monoclonal anti-βIII tubulin antibody. Images were acquired with a fluorescence microscope and corneal sub-basal nerve density was calculated on the basis of the whole mount images. Differences between the HSV-infected eyes, and comparison with normal control, were analyzed.

RESULTS

In the noninfected rabbit, the stroma was densely innervated in the central area and as a consequence the sub-basal epithelial nerve bundles were shorter, and no vortex was found. The HSV-infected corneas showed nerve damage in both epithelial and stromal nerves. Corneas infected with ICP0 and gK deletion mutants showed mild to moderate damage, while those infected with 17Syn+ and McKrae strains were seriously damaged. In the eyes infected with ICP0 and gK deletion, there were reduced numbers of sub-basal nerve bundles, but most of the corneas retained a normal stromal network. Corneas infected with 17 Syn+ and McKrae displayed destroyed nerve structures and formation of a scar tissue in the central cornea, in which only a few nerve fibers could be detected.

CONCLUSION

HSV-1 primary corneal infection seriously damages the corneal nerves, persisting for more than 4 months. Reduction of axonal transport (by gK deletion) or virus replication (by ICP0 deletion) significantly attenuated the nerve damage induced by the virus.

Increasing Incidence of Herpes Zoster Over a 60-year Period From a Population-based Study

BACKGROUND

Temporal increases in the incidence of herpes zoster (HZ) have been reported but studies have examined short study periods, and the cause of the increase remains unknown. We examined the long-term trend of HZ.

METHODS

A population-based cohort study was conducted in Olmsted County, Minnesota, using data from 1945-1960 and 1980-2007. Medical records review of possible cases was performed to confirm incident cases of HZ, the patient's immune status, and prescribing of antivirals for HZ. We examined the relative change in the temporal trend in the incidence rates before and after the introduction of the varicella vaccination program.

RESULTS

Of the 8017 patients with HZ, 58.7% were females and 6.6% were immunocompromised. The age- and sex-adjusted incidence rate of HZ increased from 0.76 per 1000 person-years (PY) (95% confidence interval [CI], .63-.89) in 1945-1949 to 3.15 per 1000 PY (95% CI, 3.04-3.26) in 2000-2007. The rate of increase across the time period was 2.5% per year after adjusting for age and sex (adjusted incidence rate ratio, 1.025 [95% CI, 1.023-1.026]; P < .001). The incidence of HZ significantly increased among all age groups and both sexes. We found no change in the rate of increase before vs after the introduction of the varicella vaccination program.

CONCLUSIONS

The incidence of HZ has increased >4-fold over the last 6 decades. This increase is unlikely to be due to the introduction of varicella vaccination, antiviral therapy, or change in the prevalence of immunocompromised individuals.

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.

Dendritic Cell Autophagy Contributes to Herpes Simplex Virus-Driven Stromal Keratitis and Immunopathology

Herpetic stromal keratitis (HSK) is a blinding ocular disease that is initiated by HSV-1 and characterized by chronic inflammation in the cornea. Although HSK immunopathology of the cornea is well documented in animal models, events preceding this abnormal inflammatory cascade are poorly understood. In this study, we have examined the activation of pathological CD4⁺ T cells in the development of HSK. Dendritic cell autophagy (DC-autophagy) is an important pathway regulating major histocompatibility complex class II (MHCII)-dependent antigen presentation and proper CD4⁺ T cell activation during infectious diseases. Using DC-autophagy-deficient mice, we found that DC-autophagy significantly and specifically contributes to HSK disease without impacting early innate immune infiltration, viral clearance, or host survival. Instead, the observed phenotype was attributable to the abrogated activation of CD4⁺ T cells and reduced inflammation in HSK lesions. We conclude that DC-autophagy is an important contributor to primary HSK immunopathology upstream of CD4⁺ T cell activation.

Herpetic stromal keratitis (HSK) is the leading cause of infectious blindness in the United States and a rising cause worldwide. HSK is induced by herpes simplex virus 1 but is considered a disease of inappropriately sustained inflammation driven by CD4⁺ T cells. In this study, we investigated whether pathways preceding CD4⁺ T cell activation affect disease outcome. We found that autophagy in dendritic cells significantly contributed to the incidence of HSK. Dendritic cell autophagy did not alter immune control of the virus or neurological disease but specifically augmented CD4⁺ T cell activation and pathological corneal inflammation. This study broadens our understanding of the immunopathology that drives HSK and implicates the autophagy pathway as a new target for therapeutic intervention against this incurable form of infectious blindness.

Congenital Corneal Anesthesia and Neurotrophic Keratitis: Diagnosis and Management

Neurotrophic keratitis (NK) is a rare degenerative disease of the cornea caused by an impairment of corneal sensory innervation, characterized by decreased or absent corneal sensitivity resulting in epithelial keratopathy, ulceration, and perforation. The aetiopathogenesis of corneal sensory innervation impairment in children recognizes the same range of causes as adults, although they are much less frequent in the pediatric population. Some extremely rare congenital diseases could be considered in the aetiopathogenesis of NK in children. Congenital corneal anesthesia is an extremely rare condition that carries considerable diagnostic and therapeutic problems. Typically the onset is up to 3 years of age and the cornea may be affected in isolation or the sensory deficit may exist as a component of a congenital syndrome, or it may be associated with systemic somatic anomalies. Accurate diagnosis and recognition of risk factors is important for lessening long-term sequelae of this condition. Treatment should include frequent topical lubrication and bandage corneal or scleral contact lenses. Surgery may be needed in refractory cases. The purpose of this review is to summarize and update data available on congenital causes and treatment of corneal hypo/anesthesia and, in turn, on congenital NK.

The use of human cornea organotypic cultures to study herpes simplex virus type 1 (HSV-1)-induced inflammation

PURPOSE

To determine the utility of human organotypic cornea cultures as a model to study herpes simplex virus type 1 (HSV-1)-induced inflammation and neovascularization.

METHODS

Human organotypic cornea cultures were established from corneas with an intact limbus that were retrieved from donated whole globes. One cornea culture was infected with HSV-1 (10(4) plaque-forming units), while the other cornea from the same donor was mock-infected. Supernatants were collected at intervals post-culture with and without infection to determine viral titer (by plaque assay) and pro-angiogenic and proinflammatory cytokine concentration by suspension array analysis. In some experiments, the cultured corneas were collected and evaluated for HSV-1 antigens by immunohistochemical means. Another set of experiments measured susceptibility of human three-dimensional cornea fibroblast constructs, in the presence and absence of TGF-β1, to HSV-1 infection in terms of viral replication and the inflammatory response to infection as a comparison to the organotypic cornea cultures.

RESULTS

Organotypic cornea cultures and three-dimensional fibroblast constructs exhibited varying degrees of susceptibility to HSV-1. Fibroblast constructs were more susceptible to infection in terms of infectious virus recovered in a shorter period of time. There were changes in the levels of select pro-angiogenic or proinflammatory cytokines that were dictated as much by the cultures producing them as by whether they were infected with HSV-1 or treated with TGF-β1.

CONCLUSION

Organotypic cornea and three-dimensional fibroblast cultures are likely useful for the identification and short-term study of novel antiviral compounds and virus replication, but are limited in the study of the local immune response to infection.

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.

Diffusion tensor magnetic resonance imaging of trigeminal nerves in relapsing herpetic keratouveitis

Background

Corneal hypoesthesia is the landmark of HSV and VZV keratitis and can lead to neurotrophic keratitis. Diffusion tensor imaging (DTI) is a new magnetic resonance imaging (MRI) derived technique, which offers possibilities to study axonal architecture. We aimed at assessing the potential impact of recurrent HSV or VZV-related keratitis on the axonal architecture of trigeminal nerves using DTI.

Design

Prospective non-interventional study.

Participants

Twelve patients and 24 controls.

Methods

DTI using MRI of the trigeminal fibers and corneal esthesiometry using the Cochet-Bonnet esthesiometer were acquired for patients affected by unilateral and recurrent HSV or VZV-related keratitis (3 months after the last corneal inflammatory event), and control subjects with no history of ocular or neuronal disease affecting the trigeminal pathways.

Main Outcome Measures

Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were compared between the 2 eyes of both patients and controls, and correlated with corneal esthesiometry.

Results

FA was lower in the trigeminal fibers ipsilateral to the affected eye compared to the non-affected side (0.39±0.02 versus 0.46±0.04, P=0.03). This difference was more important than the intra-individual variability observed in controls. Concomitantly, the asymmetry in ADC results was significantly correlated with the loss of corneal sensitivity in the affected eye.

Conclusions

Corneal hypoesthesia related to HSV and VZV keratitis is associated with persistent modifications in the architecture and functionality of the trigeminal fibers. These results add further explanation to the pathogenesis of HSV and VZV-induced neurotrophic keratitis, which may occur despite an apparent quiescence of the disease.