Ocular Manifestations of Emerging Arthropod-Borne Infectious Diseases

Ocular manifestations of West Nile virus infection: A case report and systematic review of the literature

PURPOSE

To report the case of a patient with ocular West Nile virus infection (WNVI) and to describe the demographics, eye characteristics, and treatment of patients with WNVI reported in the literature.

METHODS

Systematic literature search using the PubMed MEDLINE database searching for all cases of ocular WNVI published from inception until October 14, 2023. Inclusion criteria were patients with serologic and/or cerebrospinal fluid diagnosis of WNVI with ocular involvement.

RESULTS

A total of 60 patients (111 eyes), including the present case, were included. Most patients were males (57%), diagnosed in the United States (77%), and with a mean age at presentation of 54 years. The median time elapsed between the viral prodrome, and eye symptoms was 7 days. Neurologic involvement was present in 47 (78%) patients. Diabetes mellitus was the most frequent systemic comorbidity (45%). Posterior segment findings were present in 107 (96%) eyes. Multifocal chorioretinal lesions (86%), vitreous inflammation (51%), intraretinal hemorrhages (43%), and retinal vasculitis (21%) were the most frequent findings. Fluorescein angiography was performed in 88 (79%) eyes. Fifty-seven (51%) eyes did not receive treatment. Topical and systemic steroids were prescribed to 35% and 28% of eyes, respectively.

CONCLUSION

WNVI should be considered as a potential diagnosis in older patients who exhibit posterior uveitis, especially if they have recently experienced flu-like symptoms and have been exposed to mosquitoes. A comprehensive ocular assessment, which includes a dilated fundus examination and ocular imaging studies, can help raise suspicion for this condition even before serological confirmation is obtained.

[Viral uveitis in the tropics]

Tropical regions are characterized by a hot and humid climate that promotes the emergence or resurgence of endemic or epidemic levels of microorganisms such as viruses. Emerging viral infections are mostly inapparent, mild, or non-specific (flu-like syndrome), but they may include serious, potentially disabling or life-threatening complications. A wide array of ocular manifestations has been recently described in association with specific emerging viral infections, including arboviruses, Human T-cell Lymphotropic Virus Type 1 (HTLV-1), and Ebola. Emerging viral disease should be considered in the differential diagnosis of ocular inflammatory conditions in patients living in or returning from endemic regions. Diagnosis of emerging viral infection is confirmed with either real time polymerase chain reaction or serology. Management consists of supportive care, as there are currently no specific antiviral drug options. Corticosteroids are often used for the treatment of associated ocular inflammation. Most patients have a good visual prognosis, but there may be permanent visual impairment in some due to ocular structural complications. Prophylactic measures are essential to prevent human infection and disease.

Unraveling the Spectrum of Uveitis: Insights from an Epidemiological Study in a National Referral Center in Northern Italy

PURPOSE

Uveitis embraces a heterogeneous group of vision-threatening inflammatory conditions. Understanding uveitis epidemiology, etiology, and clinical findings is fundamental for a prompt diagnosis and optimal patient management. The aim of the study is to report the epidemiology of uveitis in a national referral center in Northern Italy and investigate the visual prognosis.

METHODS

This retrospective study was conducted at Uveitis Service (Ospedale San Raffaele) between June 2016 and May 2023. Demographic data, clinical characteristics, and etiological diagnoses of uveitis patients were collected, and visual prognosis was longitudinally explored.

RESULTS

1105 patients with uveitis were included in the study, while 47 patients presented neoplastic masquerade syndrome and have been excluded. The population had a slight majority of females (M/F ratio = 0.76), mean age was 47 years. 25% presented infectious uveitis, primarily due to herpetic etiology, toxoplasmosis, and tuberculosis. Non-infectious uveitis was the most prevalent diagnosis (38%), with sarcoidosis, HLA-B27-associated uveitis, and Fuch's uveitis as prominent causes. Anatomically, anterior segment was most frequently involved (41%). Significant improvement in visual acuity was observed at follow-up, particularly in patients with infectious uveitis.

CONCLUSIONS

Our study sheds light into the epidemiological landscape of uveitis in Northern Italy, reflecting changing patterns due to factors such as migration and changing sexual habits. In particular, higher percentages of syphilis have been observed, compared to other European reports. The distribution of non-infectious uveitis reflects other epidemiological European series. Higher percentages of neoplastic masquerade syndromes support the need of early recognition. Our findings offer precious insights for uveitis epidemiology and daily clinical practice.

"Infectious uveitis: a comprehensive systematic review of emerging trends and molecular pathogenesis using network analysis"

BACKGROUND

Infectious uveitis is a significant cause of visual impairment worldwide, caused by diverse pathogens such as viruses, bacteria, fungi, and parasites. Understanding its prevalence, etiology, pathogenesis, molecular mechanism, and clinical manifestations is essential for effective diagnosis and management.

METHODS

A systematic literature search was conducted using PubMed, Google Scholar, Web of Science, Scopus, and Embase, focusing on studies published in the last fifteen years from 2009 to 2023. Keywords included "uveitis," "infectious uveitis," "viral uveitis," and others. Rigorous inclusion and exclusion criteria were applied, and data were synthesized thematically. Gene symbols related to infectious uveitis were analyzed using protein-protein interaction (PPI) networks and pathway analyses to uncover molecular mechanisms associated with infectious uveitis.

RESULTS

The search from different databases yielded 97 eligible studies. The review identified a significant rise in publications on infectious uveitis, particularly viral uveitis, over the past fifteen years. Infectious uveitis prevalence varies geographically, with high rates in developing regions due to systemic infections and limited diagnostic resources. Etiologies include viruses (39%), bacteria (17%), and other pathogens, substantially impacting adults aged 20-50 years. Pathogenesis involves complex interactions between infectious agents and the ocular immune response, with key roles for cytokines and chemokines. The PPI network highlighted IFNG, IL6, TNF, and CD4 as central nodes. Enriched pathways included cytokine-cytokine receptor interaction and JAK-STAT signaling. Clinical manifestations range from anterior to posterior uveitis, with systemic symptoms often accompanying ocular signs. Diagnostic strategies encompass clinical evaluation, laboratory tests, and imaging, while management involves targeted antimicrobial therapy and anti-inflammatory agents.

CONCLUSION

This review underscores the complexity of infectious uveitis, driven by diverse pathogens and influenced by various geographical and systemic factors. Molecular insights from PPI networks and pathway analyses provide a deeper understanding of its pathogenesis. Effective management requires comprehensive diagnostic approaches and targeted therapeutic strategies.

Viral Anterior Uveitis: A Practical and Comprehensive Review of Diagnosis and Treatment

Anterior uveitis is the most common type of uveitis worldwide. The etiologies of anterior uveitis can be divided into infectious and non-infectious (idiopathic, autoimmune, autoinflammatory, trauma, and others). The viral pathogens most commonly associated with infectious anterior uveitis include Herpes Simplex Virus, Varicella-Zoster Virus, Cytomegalovirus, and Rubella Virus. Other emerging causes of viral anterior uveitis are West Nile Virus, Human-Immunodeficiency Virus, Epstein-Barr Virus, Parechovirus, Dengue Virus, Chikungunya Virus, and Human Herpesvirus type 6,7, and 8. Early recognition allows prompt management and mitigates its potential ocular complications. This article provides an updated literature review of the epidemiology, clinical manifestations, diagnostic tools, and treatment options for viral anterior uveitis.

[Vasculitis of the retina : Clinical aspects, diagnostics, management and treatment]

Inflammatory changes in the retinal vessels can be attributed to a wide range of etiologies. These include infections, intraocular and systemic autoimmune processes, general diseases and iatrogenic factors. As the endothelium of the retinal capillaries forms the inner blood-retinal barrier, a disruption of this structure is directly associated with consequences for the fluid electrolyte balance of the retina. Clinical sequelae can include leakage of the retinal vessels and macular edema, which are often functionally threatening and significantly reduce the quality of life of patients. As the eye can be affected as an "index organ", a work-up of the patient by the ophthalmologist is of great importance. In the age of "precision medicine", efforts are being made to gain new insights into the pathogenetic mechanisms of vasculitis through "omics" in order to develop innovative treatment concepts.

Case report: dengue fever associated acute macular neuroretinopathy

Dengue fever (DF), which is caused by the dengue virus (DENV) and transmitted through Aedes mosquitoes, is well recognized for its systemic manifestations, with its ocular involvement gaining recent attention. We present a case of a 41-year-old Taiwanese female who developed acute macular neuroretinopathy (AMN) following a DF diagnosis related to DENV-1, emphasizing the need for awareness of this complication. The patient, with a history of completely resolved optic neuritis (ON) and comorbidities, experienced blurred vision on day 10 after the onset of DF. The ophthalmic examination revealed macular edema, ellipsoid zone (EZ) infiltration, and choriocapillaris involvement. Despite pulse therapy with corticosteroids, visual disturbances persisted, highlighting the challenge of managing ocular complications. Ocular manifestations in DF include hemorrhages, inflammation, and vascular complications. DF-associated AMN, a rare presentation, poses challenges in diagnosis and treatment response evaluation. While most patients recover spontaneously, some face persistent visual impairment, especially with AMN. Our case emphasizes the importance of recognizing ocular complications in DF, necessitating a multidisciplinary approach for optimal management and further research to delineate treatment strategies and outcomes.

Arboviruses and pregnancy: are the threats visible or hidden?

Mosquito-borne arboviral diseases are a global concern and can have severe consequences on maternal, neonatal, and child health. Their impact on pregnancy tends to be neglected in developing countries. Despite hundreds of millions of infections, 90% pregnancies being exposed, scientific data on pregnant women is poor and sometimes non-existent. Recently and since the 2016 Zika virus outbreak, there has been a newfound interest in these diseases. Through various neuropathogenic, visceral, placental, and teratogenic mechanisms, these arbovirus infections can lead to fetal losses, obstetrical complications, and a wide range of congenital abnormalities, resulting in long-term neurological and sensory impairments. Climate change, growing urbanization, worldwide interconnectivity, and ease of mobility allow arboviruses to spread to other territories and impact populations that had never been in contact with these emerging agents before. Pregnant travelers are also at risk of infection with potential subsequent complications. Beyond that, these pathologies show the inequalities of access to care on a global scale in a context of demographic growth and increasing urbanization. It is essential to promote research, diagnostic tools, treatments, and vaccine development to address this emerging threat.Background The vulnerability of pregnant women and fetuses to emergent and re-emergent pathogens has been notably illustrated by the outbreaks of Zika virus. Our comprehension of the complete scope and consequences of these infections during pregnancy remains limited, particularly among those involved in perinatal healthcare, such as obstetricians and midwives. This review aims to provide the latest information and recommendations regarding the various risks, management, and prevention for pregnant women exposed to arboviral infections.

Emerging Disease of the Desert: Rise of West Nile Virus Chorioretinitis in Arizona

Purpose: To present 7 cases of West Nile virus (WNV)-related chorioretinitis in Arizona. Methods: Retina clinic charts with the terms "chorioretinitis" and "West Nile" were selected from April 1, 2012, to February 1, 2023. Results: Seven patients with initial visits between August 2019 and February 2023 were included. The majority of WNV chorioretinitis cases were seen in the last 4 years of the selected dates. Only 1 patient presented before this time but was excluded for inadequate baseline testing. All 7 patients had hospitalization for neuroinvasive disease before clinical presentation. All patients achieved a final visual acuity of 20/25 to 20/70. Conclusions: In the last 4 years of the study period, an uptrend in WNV chorioretinitis was found in our retina clinics in Arizona, reflecting the overall rise in WNV outbreaks across the state. As WNV continues to rise, the eye specialist should have high suspicion for WNV ocular disease, even in states where WNV had been an uncommon entity.

Viral infections and pathogenesis of glaucoma: a comprehensive review

Glaucoma is a leading cause of irreversible blindness worldwide, caused by the gradual degeneration of retinal ganglion cells and their axons. While glaucoma is primarily considered a genetic and age-related disease, some inflammatory conditions, such as uveitis and viral-induced anterior segment inflammation, cause secondary or uveitic glaucoma. Viruses are predominant ocular pathogens and can impose both acute and chronic pathological insults to the human eye. Many viruses, including herpes simplex virus, varicella-zoster virus, cytomegalovirus, rubella virus, dengue virus, chikungunya virus, Ebola virus, and, more recently, Zika virus (ZIKV) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), have been associated with sequela of either primary or secondary glaucoma. Epidemiological and clinical studies suggest the association between these viruses and subsequent glaucoma development. Despite this, the ocular manifestation and sequela of viral infections are not well understood. In fact, the association of viruses with glaucoma is considered relatively uncommon in part due to underreporting and/or lack of long-term follow-up studies. In recent years, literature on the pathological spectrum of emerging viral infections, such as ZIKV and SARS-CoV-2, has strengthened this proposition and renewed research activity in this area. Clinical studies from endemic regions as well as laboratory and preclinical investigations demonstrate a strong link between an infectious trigger and development of glaucomatous pathology. In this article, we review the current understanding of the field with a particular focus on viruses and their association with the pathogenesis of glaucoma.

Molecular Characterization of Bacterial Agents Causing External Ocular Infections Isolates of Patients in a Third Level Hospital

Empirical use of antibiotics in the treatment of eye infections leads to bacterial pathogens becoming resistant to antibiotics; consequently, treatment failure and eye health complications occur. The aim of this study was to describe the phenotype and genotype of the resistance and adherence of bacterial agents causing eye infections in patients at Hospital Juárez de México. An observational, prospective, cross-sectional, and descriptive study was carried out in patients with signs and symptoms of ocular infection. Bacterial agents were isolated and identified by classical microbiology and mass spectrometry. Antibiotic resistance and adherence profiles were determined. Finally, resistance (mecA/SCCmec) and virulence (icaA and icaD) genes were detected in the Gram-positive population. The results showed that blepharitis was the most prevalent condition in the study population. A MALDI-TOF analysis revealed that Staphylococcus and Pseudomonas genus were the most prevalent as causal agents of infection. Resistances to β-lactams were detected of 44 to 100%, followed by clindamycins, aminoglycosides, folate inhibitors, and nitrofurans. A multiple correspondence analysis showed a relationship between mecA genotype and β-lactams resistance. The identification of SCCmecIII and SCCmecIV elements suggested community and hospital sources of infection. Finally, the coexistence of icaA+/icaD+/mecA(SCCmecIII) and icaA+/icaD+/mecA(SCCmecIV) genotypes was detected in S. aureus. The identification of resistant and virulent isolates highlights the importance of developing protocols that address the timely diagnosis of ocular infections. Herein, implications for the failure of antimicrobial therapy in the treatment of ocular infections in susceptible patients are analysed and discussed.

Ophthalmic consequences of viral hemorrhagic fevers: Insights from the clinic and laboratory

Viral hemorrhagic fevers (VHFs) are a diverse group of RNA virus-mediated systemic diseases with significant morbidity and mortality and represent a significant public health concern. Given the high systemic morbidity and mortality in a number of these entities, delays in diagnosis can lead to downstream public health consequences. Many viral hemorrhagic fevers have ophthalmic manifestations and ophthalmologists thus play a key role in disease recognition and the management of ocular complications associated with specific hemorrhagic fevers. This review summarizes the key ophthalmic consequences of viral hemorrhagic fevers, viral disease pathogenesis, disease findings, and areas of unmet research need.

Rickettsial disease: An underestimated cause of posterior uveitis

Rickettsioses are worldwide distributed infectious disease caused by intracellular small Gram-negative bacteria transmitted to humans by the bite of contaminated arthropods, such as ticks. Systemic disease typically consists of a triad of high fever, headache, and skin rash. It usually has a self-limited course, but severe, life-threatening complications can sometimes occur. It may be clinically difficult to differentiate rickettsial diseases from other febrile illnesses. Rickettsial infection has been largely underestimated as a cause of infectious uveitis for long decades in the past. Conversely, recent data show that ocular involvement is much more common than previously thought, with retinitis, retinal vasculitis, and neuroretinitis being the most typical and frequent findings. Early clinical diagnosis of rickettsial disease, while awaiting laboratory test results, is essential for prompt initiation of appropriate antibiotic treatment to prevent systemic and ocular morbidity. The prevention remains the mainstay of rickettsial infection control.

Assessment of Dengue and Chikungunya Infections among Febrile Patients Visiting Four Healthcare Centres in Yaoundé and Dizangué, Cameroon

Dengue and chikungunya are now widely distributed in Cameroon, but there is still not enough information on their prevalence in different epidemiological settings. This study was undertaken to assess the prevalence of dengue and chikungunya in both urban and rural settings in Cameroon using three diagnostic tools. From December 2019 to September 2021, willing febrile (temperature >38 °C) outpatients visiting four healthcare facilities in the cities of Yaoundé and Dizangué were screened for dengue, and chikungunya. Clinical features of patient were recorded in a form, and their blood samples were analysed using real-time reverse transcriptase-polymerase chain reaction (rtRT-PCR), rapid diagnostic tests (RDTs) and enzyme-linked immuno-sorbent assays (ELISA). Odds ratios were used to determine the level of association between socio-demographic factors, clinical features, and infection status. The Kappa coefficient permitted to assess the level of agreement between RDTs and ELISA. Overall, 301 febrile patients were recruited in the study: 198 in Yaoundé and 103 in Dizangué. The prevalence of infection varied with the diagnostic tool used. For dengue diagnostics, 110 patients were positive to rtRT-PCR: 90 (45.45%) in Yaoundé, and 20 (19.42%) in Dizangué. The prevalence of dengue IgM using ELISA varied from 22.3% in Dizangué to 30.8% in Yaoundé. Dengue IgM rate using RDTs was 7.6% in Yaoundé and 3.9% in Dizangué. For chikungunya, one (0.5%) patient (Yaoundé, suburb) was positive to rtRT-PCR. The prevalence of chikungunya IgM according to ELISA varied from 18.4% in Dizangué to 21.7% in Yaoundé, while it was 4.5% in Yaoundé and 12.6% in Dizangué with RDTs. Only abdominal and retro-orbital pains were significantly associated with acute dengue infection. All four dengue serotypes were recorded, with a predominance of DENV-3 (35.45%) and DENV-4 (25.45%). Rapid Diagnostic Tests for either chikungunya or dengue displayed very poor sensitivity. This study further confirms the high endemicity of both dengue and chikungunya in Yaoundé and Dizangué. These data stress the need for active surveillance and the implementation of vector control measures to prevent the occurrence of outbreaks across the country.

A Comprehensive Update on Retinal Vasculitis: Etiologies, Manifestations and Treatments

Retinal vasculitis is characterized by inflammatory involvement of retinal arterioles, venules and/or capillaries and can be associated with a myriad of systemic and ophthalmic diseases. In this review, we have comprehensively discussed the etiologies, clinical manifestations, and presentations of retinal vasculitis. We have also included newer advances in imaging in retinal vasculitis such as OCTA and widefield imaging.