Utilization of multiplex polymerase chain reaction for simultaneous and rapid detection of viral infections from different ocular structures.

The impact of viral keratitis (VK) on individuals and society is notable. Early diagnosis and treatment are crucial in managing viral keratitis effectively. Timely intervention with antiviral medications and supportive care can help mitigate the severity of the infection and improve visual outcomes. We examined the prevalence of varicella-zoster virus (VZV), herpes simplex virus type 1 (HSV-1), adenovirus (AdV) and herpes simplex virus type 2 (HSV-2) in patients suspected for ocular infections. Patients included in the study exhibited various clinical manifestations indicative of ocular pathology, such as infectious keratitis, corneal scar, endogenous endophthalmitis, panuveitis, endothelitis, stromal edema, and other relevant conditions. Four different types of tear fluid, corneal samples epithelium, aqueous humor and vitreous humor were taken. After genome extraction, multiplex real-time PCR was used for diagnosis of viruses. 48 (29.6%) out of the total of 162 (100%) eye specimen were positive. The dominant prevalence was VZV (12.3%) and HSV-1 (11.7%) followed by AdV (4.9%) and HSV-2 (0.6%). There were 4 (8.3%) coinfections within the samples (HSV-1 and VZV). Aqueous humor samples demonstrated superior virus detection ability and our only HSV-2 positive sample was from aqueous humor. The utilization of multiplex real-time PCR assays in differential diagnosis of VK holds promise for expeditious diagnoses while also preventing unwarranted antibiotic prescriptions. Moreover, the aqueous humor appears to be a more sensitive site for detecting viral keratitis.

CMV neuroretinitis in an immunocompetent patient: a unique case report.

Aim: To report a case of cytomegalovirus (CMV) neuroretinitis observed in an immunocompetent patient. Materials and methods: The patient presented with a complaint of diminution of vision in both eyes (BE) and had a traumatic cataract in the right eye (RE). Fundus examination of the left eye (LE) revealed an active white, fluffy lesion with an overlying retinal hemorrhage patch with a macular star. The diagnosis of CMV neuroretinitis was established, and the patient commenced treatment with valganciclovir. Results: The patient exhibited no underlying risk factors. Subsequently, a positive response to oral valganciclovir treatment was observed. Discussion: Cytomegalovirus (CMV) neuroretinitis is typically associated with immunocompromised individuals, such as those with HIV/AIDS. The patient's presentation with a traumatic cataract in the right eye and a distinctive fundus appearance in the left eye posed a diagnostic challenge. The absence of common risk factors for CMV infection necessitated a thorough examination and consideration of rare infectious etiologies. The positive response to valganciclovir reinforces its efficacy in managing CMV-related ocular conditions. This case emphasized the necessity for ophthalmologists to maintain a high index of suspicion for CMV and other unusual pathogens when faced with neuroretinitis in patients who do not present with typical systemic immunosuppressive conditions. Early diagnosis and appropriate antiviral therapy prevent potential complications and preserve vision in such atypical presentations. Conclusion: This case underscores the importance of considering rare infectious agents in immunocompetent patients when encountering neuroretinitis, particularly in the absence of typical symptoms or signs of the disease. Abbreviations: CMV = Cytomegalovirus, BE = Both eyes, RE = Right eye, LE = Left eye, CBC = Complete Blood Count, ESR = Erythrocyte Sedimentation Rate, VDRL = Venereal Disease Research Laboratory, FTA-ABS = Fluorescent Treponemal Antibody Absorption, PPD = Purified Protein Derivative, ANA = Anti-Nuclear Antibodies, RF = Rheumatoid Factor, ACE = Anti Converting Enzyme, Ig G = Immunoglobulin G, HSV = Herpes simplex virus.

Ocular involvement in highly treatment-experienced patients with HIV.

Introduction: Ocular involvement in human immunodeficiency virus (HIV) infected and treatment-experienced patients is a significant concern, despite the advancements in antiretroviral therapy (ART) medication. The extended life expectancy of HIV patients has altered the spectrum of HIV-associated ocular diseases, ranging from minor issues to severe vision impairment or blindness. Therefore, understanding these complications becomes crucial in providing comprehensive medical care and quality of life improvement. HIV patients on multiple ARTs can experience various ocular disorders due to the complexity of their treatment regimens, drug toxicities, immune reconstitution, and opportunistic infections. Most worthy to consider are: cytomegalovirus (CMV) retinitis, immune recovery uveitis (IRU), keratoconjunctivitis sicca (dry eye syndrome), and HIV-associated neuroretinal disorders. Materials and methods: A retrospective clinical investigation was conducted on HIV/AIDS-infected patients from January 1, 2013, to December 31, 2023. The study included 62 patients over 18 years, who tested HIV-positive via enzyme-linked immunosorbent assay (ELISA) and confirmed by Western blot (WB), with assessments of HIV plasma viral load (VL) and CD4+ T cell counts (CD4). Data collected included demographics, pathological histories, clinical characteristics, blood tests, assessments for opportunistic infections, patient staging, antiretroviral therapy initiation, and disease prognosis. Results: The study found that of most patients, 37 were aged 30-39 (59.7%), with 59.7% males and 40.3% females. Most had been living with HIV for 10-19 years (35.5%). Initial CD4 counts were < 200 cells/mm3 in 46.8% of patients, which improved to 19.3% when the study was done. CMV retinitis prevalence decreased from 46.8% initially to 35.5% despite ART. Other conditions included ocular toxoplasmosis (3.22%), tuberculosis-related uveitis (1,6%), keratoconjunctivitis sicca (19.3%), and HIV retinopathy (29%). Notably, 62.1% of CMV retinitis patients experienced significant visual acuity reduction. Oral valganciclovir was beneficial for patients with CMV disease affecting multiple sites and effective for both induction and maintenance therapy of CMV retinitis. Conclusions: Managing ocular complications in HIV-experienced patients requires a multidisciplinary approach with regular ophthalmologic evaluations, prompt treatment of infections, and continuous monitoring of ART effectiveness. Early detection and intervention are crucial for preserving vision and improving outcomes. The study highlighted the importance of constant monitoring even after viral suppression. Abbreviations: HIV = Human immunodeficiency virus, ART = antiretroviral therapy, CMV = cytomegalovirus, IRU = immune recovery uveitis, ELISA = enzyme-linked immunosorbent assay, WB = Western Blot, VL = viral load, CD4 = CD4+ T cells.

Addressing corneal opacity after herpes zoster infection.

A 15-year-old boy was referred for corneal opacity evaluation. The patient had a previous herpes zoster virus (HZV) infection-varicella-zoster virus (VZV)-with ocular manifestation 1 year ago. After the infection, he developed a central corneal scar and decreased corrected distance visual acuity (CDVA) in the right eye. The slitlamp examination showed the right eye with central corneal opacity (involving anterior stroma), lacuna area between the haze, fluorescein negative, and no vascularization near the scar (Figure 1JOURNAL/jcrs/04.03/02158034-202406000-00019/figure1/v/2024-07-10T174224Z/r/image-tiff). The patient had been treated with oral valacyclovir and topical corticosteroids without any improvement of visual acuity or changes in opacity within the 1-year follow-up. His CDVA was 20/200 (-4.50 -0.75 × 25) in the right eye and counting fingers (-4.00) in the left eye. Intraocular pressure was 12 mm Hg in both eyes. Fundoscopy was normal in the right eye, but he had a macular scar in the left eye (diagnosed when he was 7 years). The left eye had no cornea signs. The patient has no comorbidity or previous surgeries. Considering this case, a corneal central scar in a 15-year-old boy, legally single eye only, and assuming it is an opacity in the anterior stroma, would you consider surgery for this patient? If so, which would you choose: Would you consider an excimer laser treatment of his ametropia while partially removing his opacity, a phototherapeutic keratectomy (PTK), or a PTK followed by a topography-guided treatment, femtosecond laser-assisted anterior lamellar keratoplasty (FALK), or deep anterior lamellar keratoplasty (DALK) or penetrating keratoplasty (depending on the scar depth)? Would you consider prophylactic acyclovir during and after surgery? Would you consider any other surgical step to prevent delayed corneal healing-persistent epithelial defect? Before the surgical approach, would you consider treating this patient with topical losartan (a transforming growth factor [TGF]-ß signaling inhibitor)? Would you first perform the surgery (which one) and then start the medication? Furthermore, if so, how long would you treat this patient? Would you consider treatment with another medication?

Overview of Cytomegalovirus Ocular Diseases: Retinitis, Corneal Endotheliitis, and Iridocyclitis.

Cytomegalovirus (CMV) infection is a significant clinical concern in newborns, immunocompromised patients with acquired immunodeficiency syndrome (AIDS), and patients undergoing immunosuppressive therapy or chemotherapy. CMV infection affects many organs, such as the lungs, digestive organs, the central nerve system, and eyes. In addition, CMV infection sometimes occurs in immunocompetent individuals. CMV ocular diseases includes retinitis, corneal endotheliitis, and iridocyclitis. CMV retinitis often develops in infected newborns and immunocompromised patients. CMV corneal endotheliitis and iridocyclitis sometimes develop in immunocompetent individuals. Systemic infections and CMV ocular diseases often require systemic treatment in addition to topical treatment.

Ocular manifestations of mpox.

PURPOSE OF REVIEW: To highlight the clinical features of mpox with an emphasis on ocular manifestations and to review treatment options for this re-emerging infectious disease. RECENT FINDINGS: Ocular involvement of mpox varies by clade. The most recent 2022 outbreak appears to be associated with fewer conjunctivitis cases compared to previous outbreaks. However, the ocular findings occurring during this newly emerging clade can be visually threatening and include cases of keratitis, rapidly progressing scleritis, and necrotizing periorbital rashes. SUMMARY: Ocular mpox is an important clinical feature of systemic mpox virus (MPXV) infection. Heightened clinical suspicion allows for a timely diagnosis and the initiation of antiviral treatment, when appropriate. Randomized clinical trials for mpox systemic and ocular treatment efficacy are lacking. Prior clinical experience with smallpox and in-vitro mpox data support the use of systemic antivirals such as tecovirimat, cidofovir, brincidofovir and topical use of trifluridine in ocular mpox management, though treatment-resistant infection can occur and portend a poor prognosis.

A Severe and Prolonged Case of Ocular Monkeypox Without Systemic Manifestations.

PURPOSE: The objective of this study was to present a rare case of prolonged and severe ocular monkeypox virus infection in the absence of systemic manifestations. METHODS: This was a single case report. RESULTS: A 60-year-old man, having been symptomatic for 9 days, presented with several umbilicated, ulcerated papules on the left cheek, left side of the nose, and left upper eyelid, along with marked follicular conjunctivitis and multiple conjunctival ulcerations. Two weeks after presentation, he developed an irregular, 360° circumferential opacity in the peripheral cornea that progressed to a large epithelial defect with corneal thinning. Although the initial eyelid lesions and conjunctivitis quickly resolved, the patient experienced nonresolving corneal inflammation manifest with peripheral corneal thinning, epithelial defects, and stromal keratitis. Four months after presentation, with the presumptive diagnosis of peripheral ulcerative keratitis, the patient was treated with intravenous steroids and immunosuppressive treatment, after which the ocular surface inflammation improved. However, the inflammation recurred 12 weeks later, and the patient developed severe perilimbal necrotizing conjunctivitis, followed by recurrence of ulcerated nodular eyelid lesions. Eight months after presentation, nucleic acid amplification tests from eyelid lesion swabs returned positive for nonvariola Orthopoxviruses , which led to the diagnosis of mpox. Within 2 weeks of beginning antiviral treatment with systemic tecovirimat and cidofovir and topical trifluridine, the eyelid lesions, conjunctivitis, and corneal inflammation resolved. CONCLUSIONS: We present an unusual and challenging case of ocular mpox with severe ocular surface inflammation including peripheral corneal thinning and epithelial defects, without systemic disease. Initiation of antiviral treatment resulted in a quick resolution of the ocular disease.

Systemic infection in aged mice causes upregulation of crystallin alpha A in the RPE/choroid.

Aging changes the responsiveness of our immune defense, and this decline in immune reactivity plays an important role in the increased susceptibility to infections that marks progressing age. Aging is also the most pronounced risk factor for development of age-related macular degeneration (AMD), a disease that is characterized by dysfunctional retinal pigment epithelial (RPE) cells and loss of central vision. We have previously shown that acute systemic viral infection has a large impact on the retina in young mice, leading to upregulation of chemokines in the RPE/choroid (RPE/c) and influx of CD8 T cells in the neuroretina. In this study, we sought to investigate the impact of systemic infection on the RPE/c in aged mice to evaluate whether infection in old age could play a role in the pathogenesis of AMD. We found that systemic infection in mice led to upregulation of genes from the crystallin family in the RPE/c from aged mice, but not in the RPE/c from young mice. Crystallin alpha A (CRYAA) was the most upregulated gene, and increased amounts of CRYAA protein were also detected in the aged RPE/c. Increased CRYAA gene and protein expression has previously been found in drusen and choroid from AMD patients, and this protein has also been linked to neovascularization. Since both drusen and neovascularization are important hallmarks of advanced AMD, it is interesting to speculate if upregulation of crystallins in response to infection in old age could be relevant for the pathogenesis of AMD.

Rapid NETosis Is an Effector Mechanism to Combat Ocular Herpes Infection.

Purpose: Neutrophils are known mediators of innate immunity, yet their effector function in herpesvirus infections remains poorly understood. Here, we elucidate the mechanistic action and pivotal role of neutrophil extracellular traps (NETs) during herpes simplex virus type 1 (HSV-1) ocular infection. Methods: Neutrophils were collected from mice for HSV-1 infection, fluorescence imaging, and immunoblotting assay. Tear samples from healthy subjects and patients with HSV-1 and mice were collected at L. V. Prasad Eye Institute, India, and at the University of Illinois, USA, respectively. For the in vivo study, C57BL/6 mice as well as diversity outbred mice were infected with HSV-1 (McKrae strain) followed by tear fluid collection at various time points (0-10 days). Samples were used for Flow cytometry, ELISA, and immunofluorescence assay. Human transcriptomic profile of keratitis dataset was used evaluate NETosis signaling pathways. We also performed neutrophil depletion studies. Results: Our data revealed a discernible temporal NET formation (NETosis) predominantly in the infected eye, across normal and diversity outbred murine models and human cases of HSV-1 infection. HSV-1 instigates swift NETosis governed by caspase-1 activation and myeloperoxidase secretion. Distinct accumulations of neutrophils, remaining unengaged in NET release in the contralateral eye post-infection, hinting at a proactive defensive posture in the uninfected eye. Moreover, neutrophil depletion accentuated ocular pathology, augmented viral load, and escalated disease scores, substantiating the protective effects of NETs in curtailing viral replication. Conclusions: Our report uncovers a previously unexplored mechanism of NETosis through pro-inflammatory cell death in response to ocular HSV-1 infection, and HPSE up-regulation, identifying new avenues for future studies.

Ocular manifestations of Monkeypox virus (MPXV) infection with viral persistence in ocular samples: A case series.

OBJECTIVE: We describe the clinical presentation and ocular viral dynamics in patients with Monkeypox virus-related ophthalmic disease (MPXROD). METHODS: In this case series, we investigated five consecutive patients with confirmed mpox, diagnosed through a positive Monkeypox virus (MPXV) Polymerase Chain Reaction (PCR) test and presenting with ocular symptoms. They were referred from the Reference Center for Sexually Transmitted Infections in São Paulo (CRT) to the Uveitis Sector at the Federal University of São Paulo, between August and December 2022. We performed PCR testing on ocular samples and culture supernatants for MPXV in all patients. Viral sequencing was conducted in one of the cases. RESULTS: Replicating MPXV was identified in at least one ocular sample of all patients, between day 31 and day 145 after the onset of skin lesions. All patients presented with keratitis, 3 with uveitis (60%) and two exhibited hypopyon (40%). The onset of ocular symptoms occurred at a mean of 21.2 days after the appearance of the first skin lesion and persisted, on average, for 61,.6 days, with a worsening trend observed until the initiation of tecovirimat treatment. Tecovirimat treatment was administered to all patients, with initiation occurring between 31 and 145 days after the onset of skin lesions. MPXV genome sequencing of an isolate from one patient classified it as belonging to lineage B1 in clade IIb. CONCLUSION: This study reveals a late onset and persistence of sight threatening ocular disease, along with potential viral infectivity even after systemic resolution in mpox cases. These findings highlight the risk of ongoing transmission from individuals with prolonged ocular manifestations, particularly through ocular discharge.

Clinical characteristics and aetiology of uveitis in a viral haemorrhagic fever zone.

BACKGROUND/OBJECTIVES: Studies on uveitis in Sierra Leone were conducted prior to the Ebola Virus Disease epidemic of 2013-16, which was associated with uveitis in 20% of survivors. They did not include imaging or investigation of tuberculosis and used laboratory services outside the country. We performed a cross-sectional study on patients presenting with uveitis to establish their clinical characteristics and identify the impact of in-country laboratory diagnoses. METHODS: We invited uveitis cases presenting to Eye Clinics in Sierra Leone from March to September 2022 to participate in the study. They underwent a diagnostic work-up, including fundus and ocular coherence tomography imaging. Active uveitis cases underwent further investigations including serology and immunological tests for syphilis, tuberculosis, herpetic viruses and HIV and chest radiographs. RESULTS: We recruited 128 patients. The median age was 34 (IQR 19) years and there was an equal gender split. Panuveitis was the predominant anatomical uveitis type (n = 51, 40%), followed by posterior uveitis (n = 36, 28%). Bilateral disease affected 40 patients (31%). Active uveitis was identified in 75 (59%) cases. ICD 11 definition of blindness with VA < 3/60 occurred in 55 (33%) uveitis eyes. Aetiology of uveitis from clinical and laboratory assessment demonstrated that most cases were of undifferentiated aetiology (n = 66, 52%), followed by toxoplasmosis (n = 46, 36%). Trauma contributed to eight (6%) cases, syphilis to 5 (4%) cases and Ebola to 2 (2%). CONCLUSIONS: Uveitis was associated with high levels of visual impairment. Posterior and panuveitis contributed to the highest proportion of uveitis cases. Laboratory studies helped differentiate syphilis as a significant aetiology of uveitis.

Acute retinal necrosis.

Acute retinal necrosis (ARN) is a rare, progressive viral uveitis, with the majority of cases caused by herpesviruses. The diagnosis of ARN is often delayed, and most patients will have some degree of permanent visual loss. We report a case of ARN in a previously healthy 32-year-old patient.

Long-term Outcomes of Surgeries for Retinal Detachment Secondary to Parasitic or Viral Infectious Retinitis.

PURPOSE: This study sought to compare the long-term outcomes of surgeries for retinal detachment (RD) secondary to viral or parasitic infectious retinitis. METHODS: A total of 47 eyes that received pars plana vitrectomy with or without scleral buckling due to RD secondary to polymerase chain reaction-proven viral (cytomegalovirus, varicella zoster virus, and herpes zoster virus) or parasitic (toxoplasma and toxocara) retinitis from October 1, 2006, to June 30, 2023, in a single medical center were retrospectively enrolled. RESULTS: Mean follow-up period was 59.03 ± 55.24 months in viral retinitis and 34.80 ± 33.78 months in parasitic retinitis after primary reattachment surgery. During follow-up, nine eyes (24.3%) with viral retinitis and five eyes (50.0%) with parasitic retinitis developed retinal redetachment. Visual acuity success at final follow-up was achieved in 19 eyes (51.4%) with viral retinitis and six eyes (60.0%) with parasitic retinitis (p = 0.64). The incidence of retinal redetachment during the 1st postoperative year was significantly higher in parasitic retinitis compared with viral retinitis (crude incidence, 0.21 vs. 0.85; p = 0.02). Hazard ratio analysis adjusted for age and sex showed 4.58-fold (95% confidence interval, 1.22-17.27; p = 0.03) increased risk of retinal redetachment in parasitic retinitis compared with viral retinitis during the 1st postoperative year. Tamponade with silicone oil and preoperative diagnostic vitrectomy were associated with significantly decreased risk of retinal redetachment in patients with parasitic retinitis. CONCLUSIONS: Compared with RD secondary to viral retinitis, RD secondary to parasitic retinitis showed higher incidence of retinal redetachment during the 1st postoperative year. Tamponade with silicone oil and preoperative diagnostic vitrectomy were associated with significantly decreased risk of retinal redetachment in patients with parasitic retinitis.

Endothelial Involvement in Monocular Mpox Keratitis: In Vivo Confocal Microscopy Approach.

PURPOSE: The aim of this study was to describe the clinical features and endothelial involvement in a case of Mpox virus keratitis by in vivo confocal microscopy (IVCM). METHODS: This is a case report. RESULTS: A 35-year-old man presented with redness, photophobia, pain, tearing, and a low visual acuity of 0.09 (decimal) in the left eye with a 6-week history of Mpox and corneal trauma. Previous testing of blood, interdigital skin lesions, and conjunctival and eyelid margin swabs confirmed the presence of Mpox by polymerase chain reaction. Biomicroscopy displayed superficial stromal infiltrates with a continuous but irregular epithelium. IVCM revealed the presence of pseudoguttata, loss of defined cell boundaries, infiltration of inflammatory cells in the endothelial layer, endothelial ridges, and precipitated pigmented granules, consistent with endotheliitis. After this episode, the patient had 4 reactivations, also treated with topical corticoids and oral tecovirimat 600 mg twice a day for 2 weeks. On the fourth reactivation, this treatment was extended to 4 weeks. On the last visit, the patient presented a visual acuity of 0.5 with disciform keratitis and reduced endotheliitis signs. The endothelial cell density remained normal during the follow-up (2763 ± 376 cell/mm 2 at baseline and 2795 ± 238 cell/mm 2 at the last visit). Polymegathism and pleomorphism showed altered values during the follow-up. CONCLUSIONS: Patients with an altered corneal epithelial barrier could suffer Mpox endotheliitis, like other DNA viruses, before disciform keratitis appears. IVCM is a useful tool for the early detection of endotheliitis and for describing its evolution, improving patient care.

Atypical phacolytic glaucoma diagnosed by biometry and anterior segment optical coherence tomography (OCT) in a patient with CMV anterior uveitis.

PURPOSE: To report a case of phacolytic glaucoma with atypical presentation in a patient which was diagnosed with biometry swept source optical coherence tomography (SS-OCT) and anterior segment spectral domain OCT (SD-OCT). METHODS: A 56-year-old male with a history of cytomegalovirus (CMV) chronic anterior uveitis in the right eye presented with a white cataract, minimal anterior chamber reaction and intraocular pressure (IOP) of 56 mmHg. Visual acuity was light perception. The anterior chamber was deep, without evidence of macroscopically visible capsular rupture. A surgical intervention was necessitated with the puzzle being whether to proceed with a trabeculectomy or a combined phaco-trabeculectomy. After a routine preoperative assessment with intraocular lens Master700, the disintegration of the natural lens was noticed. Anterior segment Spectralis OCT confirmed a lamellar separation of the anterior one third of the lens, resembling a poultaceous material. After an uneventful phacoemulsification, visual acuity was 6/6, IOP was well-controlled on maximum topical antiglaucoma treatment and no CMV recurrence was observed. RESULTS: The diagnosis of phacolytic glaucoma was established with the aid of current imaging OCT systems. Both OCT images were suggestive of a phacolytic nature of our case, despite the fact that the clinical presentation was not in concordance with such a typical case. In view of our findings the decision was to proceed with cataract extraction alone. CONCLUSION: This is the first time that we image and document the phacolytic nature of a natural lens. Our patient did not have the typical clinical presentation and was differentially diagnosed with biometry SS-OCT and confirmed by anterior segment SD-OCT.

Long-Term Corneal Endothelial Parameters of COVID-19 Patients With Ocular Surface Symptoms.

PURPOSE: This study aimed to investigate the long-term effects of COVID-19 on corneal endothelial cell morphology in patients with ocular symptoms to assess possible corneal involvement in patients who recovered. METHODS: The COVID-19 group included patients diagnosed and treated at Istanbul University Cerrahpasa Medical Faculty with confirmed SARS-CoV-2 infection and ocular irritation symptoms. The control group was comprised of age- and sex-matched individuals. The controls had no ocular pathologies. Noncontact specular microscopy (Konan Cell Check SL, Hyogo, Japan) was performed using the center method after 156 ± 16 days of COVID-19 diagnosis. Parameters such as endothelial cell density (ECD), hexagonality (HEX), coefficient of variation, and central corneal thickness were analyzed. RESULTS: Specular microscopy results of 54 COVID-19 patients with ocular irritation symptoms and 72 controls were evaluated. Ocular symptoms in COVID-19 patients included conjunctival hyperemia, foreign body sensation, tearing, ocular secretion, and chemosis. Mean (±SD) ECD was 2770 ± 31 (cells/mm 2 ) in the COVID-19 group and 2897 ± 26 in the control group, and mean (±SD) HEX was 46.52 ± 6.38 in the COVID-19 group and 58.22 ± 13.94 in the control group. COVID-19 patients exhibited significantly lower endothelial ECD and HEX levels than controls ( P = 0.003 and P < 0.001, respectively). Coefficient of variation and central corneal thickness analyses did not reach statistical significance. CONCLUSIONS: COVID-19 can cause long-term alterations in the corneal endothelial cells, leading to decreased ECD and HEX. Future research should focus on the long-term implications of COVID-19 on the corneal health and visual outcomes.