AN UNSUAL VIRAL ENDOTHELIITIS

HSV infection can affect nearly every ocular tissue. In cases of corneal involvement, the epithelium, stroma, or endothelium may be affected. Both herpes stromal keratitis (HSK) and HSV endotheliitis can present clinically with stromal opacity and, therefore, may be difficult to distinguish. In this case we will be describing a viral endotheliitis with a particular aspect on the corneal endothelium.

Microsporidia-induced stromal keratitis: a new cause of presumed immune stromal (interstitial) keratitis

Background and objectiveTo describe the clinical features, diagnosis and management of immune stromal keratitis/interstitial keratitis (IK) associated with microsporidial epithelial keratitis.MethodsBetween October 2020 and January 2021, medical records of IK patients microbiologically proven as microsporidia from samples collected from corneal epithelium on smear examination, and/ or molecular analysis were reviewed. Demography, clinical profile and treatment were analysed. Real-time PCR (RT-PCR) for adenovirus (ADV), Epstein-Barr virus (EBV), herpes simplex virus (HSV) and varicella-zoster virus (VZV) was done.ResultsTwenty of 152 (13%) microbiologically proven cases of microsporidial keratitis were diagnosed as IK during the study period, the mean age and duration of symptoms were 35.7±11.4 years and 46.3±27.7 days, respectively. Half had predisposing risk factors, like trauma; and 30% had prior recurrences. One-fourth of patients were using antivirals on presentation. Characteristic presentations included disciform keratitis(n=12), incomplete/complete ring(n=5), and combination(n=3), along with variable subepithelial infiltrates (n=14). All cases had stromal oedema, with an intact epithelium and fine pigment dusting on endothelium. Corneal epithelial scrapings had scanty microsporidia spores in smears of 17/20 (85%), and pan-microsporidial DNA was identified in 14/20 (70%), with Vittaforma corneae by sequencing in 11/20 (55%). Other viruses detected were ADV (14,70%), VZV (2,10%), EBV (1,5%) and HSV (1,5%). Rapid resolution of inflammation and oedema within 2 weeks of starting steroids was seen in all cases.ConclusionMicrosporidia epithelial keratitis induced stromal inflammatory keratitis; is distinguished from microsporidial keratoconjunctivitis and stromal keratitis, by characteristic clinical features, and response to topical steroids.

Human Adenovirus Species D Interactions with Corneal Stromal Cells

Notable among the many communicable agents known to infect the human cornea is the human adenovirus, with less than ten adenoviruses having corneal tropism out of more than 100 known types. The syndrome of epidemic keratoconjunctivitis (EKC), caused principally by human adenovirus, presents acutely with epithelial keratitis, and later with stromal keratitis that can be chronic and recurrent. In this review, we discuss the current state of knowledge regarding the molecular biology of adenovirus infection of corneal stromal cells, among which the fibroblast-like keratocyte is the most predominant, in order to elucidate basic pathophysiologic mechanisms of stromal keratitis in the human patient with EKC.

OPTN limits herpes stromal keratitis severity and demyelination through negative regulation of IL-17 and hyperinflammatory T-cell response

Herpes stromal keratitis (HSK) is a result of the inflammatory sequelae following primary and recurrent Herpes simplex virus type-1 (HSV-1) infections. This pathology is known to be mediated by immunopathogenic T cell responses against viral antigens, however most individuals infected with HSV-1 never exhibit signs of this immunopathology. Recent studies have identified the host restriction factor, optineurin (OPTN), as an inhibitor of viral spread in the central nervous system, protecting hosts from viral encephalopathy. In an HSV-1 corneal infection mouse model on OPTN knockout mice, we assess the contribution of OPTN to ameliorating the clinical manifestations of HSK. We identify that OPTN protects the host from loss of ocular and whisker sensitivity and opacification of the cornea. scRNA-seq of the trigeminal ganglion (TG) reveals that transcription changes to the peripheral neurons and immune cell populations drive the expression of Il-17A in CD4 and CD8 T cells, as well as increased infiltration of T cells into the TG. This leads to demyelination and the observed HSK pathology.

Ophthalmic manifestations of herpes virus infection in dogs

This article describes the main aspects of the epizootology and pathogenesis of Cahv-1 (canine herpesvirus), also, the clinical forms of manifestations of pathology in dogs of different ages and physiological status are described. Particular attention is paid to ocular pathologies developing at Cahv-1, such as herpetic conjunctivitis, blepharitis, ulcerative and stromal keratitis. The features of the diagnosis and differentiation of these pathologies are described. The systematic and local medicines used by us in the practice of treating dogs with herpetic eye, the principles and algorithms of their prescription are presented. The difficulties of diagnostics Cahv-1 are described, and the reasons for frequent false-negative results during PCR explained in the article. Besides additional laboratory verification methods for Cahv-1 as well as methods of prevention of herpetic infection of dogs are indicated.

Acute Stromal Keratitis Following the Vitrectomy for the Treatment of Myopic Tractional Maculopathy in Lupus

Purpose: To report a case of acute stromal keratitis after vitrectomy for the treatment of myopic tractional maculopathy in a lupus patient.Case summary: A lupus patient who were treated with low dose steroid complained of decreased visual acuity due to myopic tractional maculopathy with fovea detachment. No evidence of intraocular inflammation was observed. The best-corrected visual acuity (BCVA) was 20/40. We performed the vitrectomy and removal of epiretinal membrane and internal limiting membrane. BCVA of 20/80 at day 1 decreased to hand motion at day 5. Severe corneal edema and superficial punctate keratitis that were observed did not improve three days after the anti-herpetic treatment. Based on this, we diagnosed her as immune-mediated acute stromal keratitis in lupus, and treated with oral methylprednisolone of 20 mg. The corneal edema improved rapidly following high dose systemic steroid. Myopic fovea detachment also improved. Improvement of BCVA was limited to 20/80 at six months, compared to the baseline one.Conclusions: We observed the development of acute stromal keratitis after vitrectomy for the myopic tractional maculopathy in the patient with lupus. High dose systemic steroid improved this corneal complication. Increased dose of systemic steroid should be considered before and after vitrectomy in lupus patients.

Chronic and Recurrent Herpes Zoster Ophthalmicus

Background and Objectives: This study sought to investigate the natural course, the chronicity and recurrence rate, and the risk factors of chronic and recurrent herpes zoster ophthalmicus (HZO). We also evaluated the effects of long-term treatment for HZO. Materials and Methods: Patients diagnosed and treated for HZO were included in the retrospective medical chart review. Multivariable-adjusted logistic and Cox regression models were used to show risk factors for chronic and recurrent HZO along with hazard ratios (HRs) and 95% confidence intervals (CIs). Results: Among a total 130 of HZO patients, 31 patients (23.85%) had chronic disease and 19 patients (14.62%) had recurrent disease. The rate of chronic disease was higher in HZO with conjunctivitis, epithelial keratitis, and stromal keratitis. The recurrence rate increased in patients with chronic HZO (HR: 34.4, 95% CI: 3.6–324.6), epithelial keratitis (HR: 5.5, 95% CI: 1.3–30.0), stromal keratitis (HR: 18.8, 95% CI: 3.0–120.8), and increased intraocular pressure (IOP) (HR: 7.3, 95% CI: 1.6–33.2). Length of systemic antiviral therapy and anti-inflammatory eyedrop treatment were not associated with recurrent HZO (p = 0.847 and p = 0.660, respectively). The most common ocular manifestation for recurrent HZO was stromal keratitis. Conclusions: This study demonstrated a considerable frequency of chronic and recurrent HZO. Chronic HZO in the form of epithelial or stromal keratitis with increased IOP provoked a significant rise in the risk of recurrence.

Advancing Our Understanding of Corneal Herpes Simplex Virus-1 Immune Evasion Mechanisms and Future Therapeutics

Herpes stromal keratitis (HSK) is a disease that commonly affects the cornea and external eye and is caused by Herpes Simplex Virus type 1 (HSV-1). This virus infects approximately 66% of people worldwide; however, only a small portion of these people will develop symptoms in their lifetime. There is no cure or vaccine available for HSV-1; however, there are treatments available that aim to control the inflammation caused by the virus and prevent its recurrence. While these treatments are beneficial to those suffering with HSK, there is a need for more effective treatments to minimise the need for topical steroids, which can have harmful effects, and to prevent bouts of disease reactivation, which can lead to progressive corneal scarring and visual impairment. This review details the current understanding of HSV-1 infection and discusses potential novel treatment options including microRNAs, TLRs, mAbs, and aptamers.

Reactivation of herpes simplex keratitis following vaccination for COVID-19

An 82-year-old man with a history of herpes simplex keratitis 40 years previously presented with recurrence, 1 day following vaccination for novel COVID-19. His condition worsened despite topical treatment with ganciclovir gel. A diagnosis of herpetic stromal keratitis was made, requiring systemic aciclovir, topical prednisolone, moxifloxacin and atropine, and oral doxycycline. He improved clinically on treatment, with some residual corneal scarring. Visual acuity improved from 6/36 corrected at presentation, to 6/24 following treatment. Clearly, public and personal health benefits from vaccination are hugely important and we would not suggest avoiding vaccination in such patients. It is, however, important for ophthalmic providers to be aware of the rare potential for reactivation of herpetic eye disease following vaccination to enable prompt diagnosis and treatment.