COVID-19 and Its Ophthalmic Manifestations: A Literature Review

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel coronavirus discovered in late 2019 in Wuhan, Hubei Province, China. The virus has now developed into a full-scale global pandemic affecting hundreds of millions of people to date. A majority of cases present with nonspecific acute upper respiratory symptoms. A wide range of systemic symptoms has been reported, with some patients presenting with nonspecific extrapulmonary symptoms. Recently, there has been an increased association of COVID-19-positive patients presenting with ocular symptoms. As an increasing number of patients present with ophthalmic manifestations, recognizing these visual symptoms is of utmost importance. Some patients may present with ocular symptoms as the first indication of COVID-19 infection; quickly isolating and starting treatment can aid in stopping the spread of this novel coronavirus. This review will describe the current epidemiology and pathophysiology of SARS-CoV-2, emphasizing the ophthalmic manifestations and their clinical course progression. Further, we will be reporting on the growing number of rare ocular manifestations that have occurred in some COVID-19-positive patients, along with the route of transmission, specific manifestations, and the treatment methods for both these pulmonary and extrapulmonary symptoms, specifically the ocular manifestations.

Human conjunctiva organoids to study ocular surface homeostasis and disease

The conjunctival epithelium covering the eye contains two main cell types: mucus-producing goblet cells and water-secreting keratinocytes, which present mucins on their apical surface. Here, we describe long-term expanding organoids and air-liquid interface representing mouse and human conjunctiva. A single-cell RNA expression atlas of primary and cultured human conjunctiva reveals that keratinocytes express multiple antimicrobial peptides and identifies conjunctival tuft cells. IL-4/-13 exposure increases goblet and tuft cell differentiation and drastically modifies the conjunctiva secretome. Human NGFR+ basal cells are identified as bipotent conjunctiva stem cells. Conjunctival cultures can be infected by herpes simplex virus 1 (HSV1), human adenovirus 8 (hAdV8), and SARS-CoV-2. HSV1 infection was reversed by acyclovir addition, whereas hAdV8 infection, which lacks an approved drug therapy, was inhibited by cidofovir. We document transcriptional programs induced by HSV1 and hAdV8. Finally, conjunctival organoids can be transplanted. Together, human conjunctiva organoid cultures enable the study of conjunctival (patho)-physiology.

Molecular, Epidemiological and Clinical Assessment of Adenoviral Keratoconjunctivitis in Egypt: Institutional Study

PURPOSE

To evaluate the frequency of Human adenovirus (HAdV) and its serotypes in keratoconjunctivitis patients who attended the outpatient clinics of Mansoura Ophthalmic Center, Egypt.

METHODS

Conjunctival secretions and corneal scrapings were collected from patients complaining of clinically diagnosed viral keratoconjunctivitis. The molecular method for HAdV detection was performed by polymerase chain reaction (PCR) followed by restriction enzymes (REA) determination of serotypes for hexone gene.

RESULTS

HAdV infection was detected in 38% of samples. There were 4 serotypes of Human adenovirus species D (HAdV-D) isolated (4, 8, 37, 3), where HAdV-D8 was the most dominant. Contact with infected patient, follicular conjunctivitis and subepithelial corneal infiltrates are useful features for clinical diagnosis of adenoviral conjunctivitis.

CONCLUSION

HAdV was significant etiological factor of acute follicular conjunctivitis. Accurate diagnosis of adenoviral conjunctivitis is essential for appropriate management, reducing permanent visual impairment and to limit the transmission of the virus within the community.

[Ophthalmic manifestations of COVID-19]

In March 2020 the World Health Organization (WHO) declared a pandemic of the novel coronavirus infection (COVID-19) caused by the SARS-CoV-2 respiratory virus. The high spread rate of the virus and the severity of the course of the disease are of great clinical and epidemiological significance, making it relevant for ophthalmologists to study the mechanisms of how SARS-CoV-2 infects ocular structures, as well as possible clinical manifestations of the infection in the organ of vision. This review contains analysis, systematization, and generalization of epidemiological and clinical data on SARS-CoV-2 ocular lesions and was carried out with the data found in scientific abstract databases. The article presents main clinical ophthalmic manifestations of COVID-19, lists the utilized schemes of etiotropic and symptomatic therapy, recommended preventive measures, and considers the possible ophthalmic complications after vaccination against COVID-19.

Ocular Surface Infection Mediated Molecular Stress Responses: A Review

Infection mediated ocular surface stress responses are activated as early defense mechanisms in response to host cell damage. Integrated stress responses initiate the host response to different types of infections and modulate the transcription of key genes and translation of proteins. The crosstalk between host and pathogen results in profound alterations in cellular and molecular homeostasis triggering specific stress responses in the infected tissues. The amplitude and variations of such responses are partly responsible for the disease severity and clinical sequelae. Understanding the etiology and pathogenesis of ocular infections is important for early diagnosis and effective treatment. This review considers the molecular status of infection mediated ocular surface stress responses which may shed light on the importance of the host stress-signaling pathways. In this review, we collated literature on the molecular studies of all ocular surface infections and summarize the results from such studies systematically. Identification of important mediators involved in the crosstalk between the stress response and activation of diverse signaling molecules in host ocular surface infection may provide novel molecular targets for maintaining the cellular homeostasis during infection. These targets can be then explored and validated for diagnostic and therapeutic purposes.

COVID-19 and conjunctivitis: a meta-analysis

COVID-19 is a disease first identified in Wuhan City, Hubei Province, China, in December 2019, causes by a SARS-COV-2 virus infection. By 27 October 2020, 43,921,473 confirmed cases were reported worldwide, with 1,166,389 COVID-19 deaths. Conjunctivitis has been reported in adults and pediatric patients with COVID-19.

COVID-19 and the eye: a review

BACKGROUND

To provide a review for general practitioners and medical specialists about the most common eye complaints and ocular manifestations in a COVID-19 patient.

METHODS

Reviewed 50 articles referenced in 4 databases from 20 December 2019 to 16 September 2020.

RESULTS

Of the 50 articles reviewed, 26 met the criteria for analysis and were included in the study. Among them were 5 reviews, 6 case series, 7 case reports, 4 cross-sectional studies, 2 systematic reviews, 1 cohort study and 1 correspondence. We found that the prevalence of ocular manifestations in patients during the course of COVID-19 varied between 0.8% and 31.6%, depending on the study design. Symptoms of acute conjunctivitis were the most frequent clinical findings. Acute phase reactants were also correlated to ocular manifestations and the severity of the systemic disease in many reports.

CONCLUSIONS

Ocular manifestations are not uncommon in COVID-19 patients and have been associated with higher levels of acute phase reactants as well as a higher degree of severity of the systemic disease. We recommend that all physicians consider COVID-19 as a differential diagnosis in the presence of acute conjunctivitis with or without systemic symptoms.

Very late onset corneal haze in a photorefractive keratectomy patient associated with presumed viral keratoconjuctivitis

We report a rare case of very late-onset haze triggered by viral conjunctivitis, >20 years after treatment of moderate myopia with photorefractive keratectomy (PRK), and its successful management.

A Review of the Differential Diagnosis of Acute Infectious Conjunctivitis: Implications for Treatment and Management

The diagnosis of acute infectious conjunctivitis can be difficult. Clinical ambiguity exists between the acute viral and bacterial as well as the allergic forms, which can confound diagnosis. Also, discrimination between viral or bacterial origins of infectious conjunctivitis based on historical, nonspecific, clinical signs and symptoms contributes to a high rate of misdiagnosis and overuse of antibiotic treatment. Therefore, in order to effectively treat acute infectious conjunctivitis, physicians must be aware of the clinical signs and symptoms and available diagnostic tests that can provide a more accurate differential diagnosis.

Effect of diluted povidone iodine in adenoviral keratoconjunctivitis on the rate of subepithelial corneal infiltrates

AIM

To evaluate the clinical characteristics of adenoviral keratoconjunctivitis, the management modalities, as well as the incidence of subepithelial corneal infiltrates (SEI).

METHODS

Patients with characteristic clinical symptoms and signs, who presented to our clinic within the first week of symptoms and received the diagnosis of adenoviral keratoconjunctivitis between January 2013 and April 2016, were included in the study. A total of 211 patients were included in the study. Patients were evaluated for the incidence of clinical signs, late complications, management preferences, and the effect of diluted povidone-iodine (d-PVP-I) 2%.

RESULTS

Patients' mean age was 33.03±14.76y. We observed an increase in the number of cases according to the years. At presentation and/or early follow-up, the clinical signs were conjunctival hyperemia (100%), conjunctival follicules (79.1%), edema of the eyelids (39.3%), chemosis (16.1%), pseudomembrane formation (16.6%), and corneal epitheliopathy (29.9%). During late follow-up 13.3% patients developed conjunctival subepithelial fibrosis, and 39.8% developed SEI. A significant decrease in the incidence of SEI development was observed in patients who used d-PVP-I 2% (P=0.032; 33.3% vs 45.9%, respectively in patients who received d-PVP-I 2% and who did not).

CONCLUSION

Adenoviral keratoconjunctivitis has a tremendous effect on patient's comfort and abilities in short-term. Additionally, almost half of the patients develop visual problems related to SEI. According to our clinical experience, using d-PVP-I 2% in the first days of adenoviral keratoconjunctivitis might be helpful in reducing the risk of SEI as a complication.

The prevalence of adenoviral conjunctivitis at the Clinical Hospital of the State University of Campinas, Brazil

OBJECTIVES

Viral conjunctivitis is a common, highly contagious disease that is often caused by an adenovirus. The aim of this study was to evaluate the prevalence of adenoviral conjunctivitis by analyzing data from a prospective clinical study of 122 consecutively enrolled patients who were treated at the Clinical Hospital of the State University of Campinas (UNICAMP) after a clinical diagnosis of infectious conjunctivitis between November 2011 and June 2012.

METHODS

Polymerase chain reaction was used to evaluate all cases of clinically diagnosed infectious conjunctivitis and based on the laboratory findings, the prevalence of adenoviral infections was determined. The incidence of subepithelial corneal infiltrates was also investigated.

RESULTS

Of the 122 patients with acute infectious conjunctivitis included, 72 had positive polymerase chain reaction results for adenoviruses and 17 patients developed subepithelial corneal infiltrates (13.93%).

CONCLUSIONS

The polymerase chain reaction revealed that the prevalence of adenoviral conjunctivitis was 59% in all patients who presented with a clinical diagnosis of infectious conjunctivitis from November 2011 to June 2012. The prevalence of adenoviral conjunctivitis in the study population was similar to its prevalence in other regions of the world.

Delayed epithelial ingrowth caused by viral conjunctivitis after LASIK

To report a patient who presented with epithelial ingrowth caused by viral keratoconjunctivitis 3 months after LASIK surgery. A 41-year-old man presented with decreased visual acuity in the right eye, which had developed about 3 weeks before. He had undergone LASIK surgery 3 months prior without complications. Two months after the surgery, he was treated for viral conjunctivitis. During the treatment period, filamentary keratitis developed, and a therapeutic bandage contact lens was applied for 2 weeks. Upon presentation, examination revealed a corrected visual acuity of 20/100 and irregular epithelial sheets under the edematous flap. The flap was lifted, and the in-grown epithelium was removed. The flap was repositioned with double continuous 10-0 nylon sutures. Post-operatively, the patient developed a mild diffuse lamellar keratitis that resolved rapidly with topical corticosteroid treatment. At 2 months, the corrected visual acuity was 20/20 without interface opacities. As the patient showed no complications prior to viral conjunctivitis, we suspect that the viral infection caused edema of the corneal flap, which caused epithelial ingrowth under the flap. Patients who have viral conjunctivitis after LASIK surgery should be examined carefully and managed with consideration of flap complications.