New infectious etiologies for posterior uveitis

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.

Fungi of the human eye: Culture to mycobiome

The focus of the current review is multi-fold and compares the diversity and abundance of fungi on the ocular surface by the conventional culture-based method with the more sensitive, high throughput, culture-independent NGS method. The aim is to highlight the existence of a core ocular mycobiome and explore the transition of the ocular fungal microbiota from the normal eye to the diseased eye. PubMed, Google Scholar and Medline were used to search for publications and reviews related to cultivable fungi and the mycobiome of the normal and diseased eye. The conventional cultivable approach and the NGS approach confirm that the eye has its own mycobiome and several confounding factors (age, gender, ethnicity etc.) influence the mycobiome. Further, dysbiosis in the mycobiome appears to be associated with ocular diseases and thus impacts the health of the human eye. Considering that the mycobiome of the eye is influenced by several confounding factors and also varies with respect to the disease status of the eye there is a need to extensively explore the mycobiome under different physiological conditions, different ethnicities, geographical regions etc. Such studies would unravel the diversity and abundance of the mycobiomes and contribute to our understanding of ocular health. Research focused on ocular mycobiomes may eventually help to build a targeted and individualized treatment.

Practical Guidance for Clinical Microbiology Laboratories: Diagnosis of Ocular Infections

The variety and complexity of ocular infections have increased significantly in the last decade since the publication of Cumitech 13B, Laboratory Diagnosis of Ocular Infections (L. D. Gray, P. H. Gilligan, and W. C. Fowler, Cumitech 13B, Laboratory Diagnosis of Ocular Infections, 2010). The purpose of this practical guidance document is to review, for individuals working in clinical microbiology laboratories, current tools used in the laboratory diagnosis of ocular infections. This document begins by describing the complex, delicate anatomy of the eye, which often leads to limitations in specimen quantity, requiring a close working bond between laboratorians and ophthalmologists to ensure high-quality diagnostic care. Descriptions are provided of common ocular infections in developed nations and neglected ocular infections seen in developing nations. Subsequently, preanalytic, analytic, and postanalytic aspects of laboratory diagnosis and antimicrobial susceptibility testing are explored in depth.

Clinical course of choroidal neovascular membrane in West Nile virus chorioretinitis: a case report

Background

This report describes the clinical course of choroidal neovascular membrane (CNV) in West Nile virus-associated chorioretinitis.

Case presentation

A 28-year-old Italian woman was referred to our institution because of reduced visual acuity in the left eye dating back 4 months. A diagnosis of retinal vasculitis in the right eye and chorioretinitis with CNV in the left eye was made. A complete workup for uveitis revealed positivity only for anti-West Nile virus immunoglobulin M (IgM), while immunoglobulin G (IgG) was negative. Whole-body computed tomography and nuclear magnetic resonance imaging of the brain were also negative. Therefore, the patient was treated with a combination of oral prednisone (starting dose 1 mg/kg per day) and three intravitreal injections of bevacizumab 1.25 mg/0.05 ml, 1 month apart. Fourteen days from starting corticosteroid therapy and after the first intravitreal injection, the patient experienced increased visual acuity to 0.4. Response to therapy was monitored by clinical examination, ocular coherence tomography (OCT), OCT angiography and retinal fluorescein angiography. Three months later, resolution of CNV in the left eye was achieved and no signs of retinal vasculitis were detected in the right eye, while serum IgM for West Nile virus turned negative and IgG positive.

Conclusion

CNV may be a complication of West Nile virus-associated chorioretinitis, and only subclinical retinal vasculitis may also be found even in non-endemic regions.

Case Report: Japanese Encephalitis Associated with Chorioretinitis after Short-Term Travel to Bali, Indonesia

Japanese encephalitis (JE) virus is a mosquito-borne flavivirus endemic throughout Asia. Incidence in non-endemic countries is rare, with an estimate of less than one case per one million travelers. Most human JE infections are asymptomatic or cause a mild, nonspecific febrile illness. Neurological involvement, if present, is usually severe and associated with high mortality or ongoing neurological sequelae in survivors. Ocular manifestations are rare with JE, but uveitis has been described to be associated with other flavivirus infections, including West Nile virus. We report the first probable case of JE chorioretinitis acquired by a 45-year-old Australian traveler to Bali. This case highlights the importance of a detailed ocular examination when there is clinical suspicion of JE.

The challenging management of Rift Valley Fever in humans: literature review of the clinical disease and algorithm proposal

Rift Valley Fever (RVF) is an emerging zoonotic arbovirus with a complex cycle of transmission that makes difficult the prediction of its expansion. Recent outbreaks outside Africa have led to rediscover the human disease but it remains poorly known. The wide spectrum of acute and delayed manifestations with potential unfavorable outcome much complicate the management of suspected cases and prediction of morbidity and mortality during an outbreak. We reviewed literature data on bio-clinical characteristics and treatments of RVF human illness. We identified gaps in the field and provided a practical algorithm to assist clinicians in the cases assessment, determination of setting of care and prolonged follow-up.

Tick- borne infection revealing human immunodeficiency virus (HIV) positivity in a young adult

Purpose

To describe a patient whose retinal findings suggestive of tick-borne disease but evaluations led to early diagnosis and treatment of human immunodeficiency virus (HIV) infection.

Observation

A young patient presented with bilateral uveitis, branch retinal artery occlusion and retinal findings suggestive of infective/inflammatory etiology. Laboratory evaluations revealed that the patient was positive for co-infection with Rickettsia conorii and Bartonella henselae. On further investigation, the patient tested positive for HIV infection. The patient was treated with doxycycline as well as highly active anti-retroviral therapy (HAART) to control both opportunistic infections as well as HIV infection.

Conclusion and Importance

Patients with HIV infection are at risk for multiple, simultaneous opportunistic co-infections, including those with tick-borne diseases.

Infectious uveitis: an Asian perspective

Several intraocular infections can present with protean manifestations posing major diagnostic and management challenges. Infections such as tuberculosis, dengue and chikungunya fever have continued to remain major endemic diseases that are associated with uveitis in the Asia Pacific region. These entities often require a high index of clinical suspicion and laboratory analysis including assays of ocular fluids and/or tissues for confirmation of the diagnosis. Infectious uveitis caused by tuberculosis, dengue and chikungunya can present with characteristic clinical features and imaging findings on ancillary investigations; that may provide clue to the early diagnosis. Use of modern imaging modalities such as enhanced-depth imaging optical coherence tomography, optical coherence tomography angiography and ultra-wide field fundus photography greatly aid in the evaluation of these conditions. In the current review, we have discussed the epidemiology, clinical phenotypes, imaging characteristics, diagnosis and management of uveitis caused by tuberculosis, dengue and chikungunya.

Review for Disease of the Year: Treatment of Viral Anterior Uveitis: A Perspective

PURPOSE

To define a clinically tailored therapeutic strategy for the treatment of viral anterior uveitis (VAU).

METHODS

A PubMed search spanning the past 5 years was conducted using the MesH-terms "viral anterior uveitis" and "therapy."

RESULTS

The herpes simplex virus (HSV), the varicella zoster virus (VZV), and the cytomegalovirus (CMV) are the predominant pathogens in VAU. Other viruses, including rubella, chikungunya, and zika, have been linked with distinct forms of the disease. Depending on the causative agent and the host immunocompetence, the mainstay treatment for suspected VAU is a combination of topical or systemic antivirals and topical corticosteroids, supplemented with cycloplegics and intraocular-pressure-lowering medication.

CONCLUSIONS

Oral acyclovir, valacyclovir, and famciclovir are the mainstay of treatment for HSV- and VZV-induced infections. Brivudin serves as an alternative in insufficiently responsive cases. CMV-induced infections respond well to valganciclovir. A 3- to 12-month course of prophylactic treatment against recurrences is worth considering.

Seroprevalence against Rickettsia and Borrelia Species in Patients with Uveitis: A Prospective Survey

Vector-borne diseases such as Lyme borreliosis and rickettsioses have been associated with ocular inflammation. Our aim was to study patients with diagnosed uveitis to evaluate serological signs of infection or exposure to these tick-borne agents. Forty-eight patients were prospectively examined with serology together with medical records and a questionnaire concerning previous exposure, diseases, and treatments. Seven patients (14.6%) showed seroconversion to Rickettsia spp. between acute and convalescent phase sera, which provides support for a positive Rickettsia diagnosis according to guidelines. The specificity was confirmed by Western blot. Additional 28 patients had stationary titres of which eight (16.6%) had 1 : 256 or higher titre in the first serum, and another 13 patients were seronegative. No epidemiological risk factor or marker could be identified. For Borrelia, only three patients showed moderate IgG titres. A control group of 100 blood donors, 60 patients with rheumatic disease, and 56 patients seeking medical care were tested of which 2.0–7.1% showed low anti-Rickettsia titres and 3.0–8.3% anti-Borrelia titres. The findings are indicative for an association between infection or exposure to Rickettsia spp. and uveitis with a seropositivity among patients with recurrent uveitis in concordance with the spread of rickettsial exposure in a tick-exposed population.

Viral posterior uveitis

The causes of posterior uveitis can be divided into infectious, autoimmune, or masquerade syndromes. Viral infections, a significant cause of sight-threatening ocular diseases in the posterior segment, include human herpesviruses, measles, rubella, and arboviruses such as dengue, West Nile, and chikungunya virus. Viral posterior uveitis may occur as an isolated ocular disease in congenital or acquired infections or as part of a systemic viral illness. Many viruses remain latent in the infected host with a risk of reactivation that depends on various factors, including virulence and host immunity, age, and comorbidities. Although some viral illnesses are self-limiting and have a good visual prognosis, others, such as cytomegalovirus retinitis or acute retinal necrosis, may result in serious complications and profound vision loss. Since some of these infections may respond well to antiviral therapy, it is important to work up all cases of posterior uveitis to rule out an infectious etiology. We review the clinical features, diagnostic tools, treatment regimens, and long-term outcomes for each of these viral posterior uveitides.

A new era of uveitis: impact of polymerase chain reaction in intraocular inflammatory diseases

Uveitis is a sight-threatening intraocular inflammatory disorder which may occur from both infectious and non-infectious or autoimmune causes. The frequency of infectious uveitis and autoimmune uveitis varies depending on countries and regions. According to a nationwide survey conducted by the Japanese Ocular Inflammation Society, infectious and non-infectious uveitis accounted for 16.4 and 50.1% of new patients, respectively while the remaining 33.5% of new uveitis cases were not classified or were idiopathic uveitis. Infectious uveitis is particularly important because it causes tissue damage to the eye and may result in blindness unless treated. However, it can be treated if the pathogenic microorganisms are identified promptly and accurately. Remarkable advancements in molecular and immunological technologies have been made in the last decade, and the diagnosis of infectious uveitis has been greatly improved by the application of molecular and immunological investigations, particularly polymerase chain reaction (PCR). PCR performed on a small amount of ocular samples provides a prompt, sensitive, and specific molecular diagnosis of pathogenic microorganisms in the eye. This technology has opened a new era in the diagnosis and treatment of uveitis, enabling physicians to establish new clinical entities of uveitis caused by infectious microorganisms, identify pathogens in the eyes of many patients with uveitis, and determine prompt diagnosis and appropriate therapy. Here we review the PCR process, new PCR tests specialized for ocular diseases, microorganisms detected by the PCR tests, diseases in the eye caused by these microorganisms, and the clinical characteristics, diagnosis, and therapy of uveitis.

Ophthalmologic aspects of chikungunya infection

Chikungunya fever, a viral disease epidemic in some parts of the world is newly introduced in the Americas. This is of considerable international concern, with a growing incidence owing to developing urbanization, tourism, and trade. Ocular manifestations of chikungunya fever are not frequent, but of great relevance. Common manifestations include conjunctivitis, optic neuritis, iridocyclitis, episcleritis, retinitis and uveitis. Diagnostic and monitoring investigations would include optical coherence tomography, fundus fluorescein and indocyanine green angiography, visual field analysis, and electrophysiologic tests. There have been no prospective, randomized therapeutic trials, and it is unclear if the disease is self-limiting or if treatment is actually beneficial. Prognosis varies, ranging from full resolution to permanent vision loss despite intervention.

Infectious Uveitis

Infectious uveitis is one of the most common and visually devastating causes of uveitis in the US and worldwide. This review provides a summary of the identification, treatment, and complications associated with certain forms of viral, bacterial, fungal, helminthic, and parasitic uveitis. In particular, this article reviews the literature on identification and treatment of acute retinal necrosis due to herpes simplex virus, varicella virus, and cytomegalovirus. While no agreed-upon treatment has been identified, the characteristics of Ebola virus panuveitis is also reviewed. In addition, forms of parasitic infection such as Toxoplasmosis and Toxocariasis are summarized, as well as spirochetal uveitis. Syphilitic retinitis is reviewed given its increase in prevalence over the last decade. The importance of early identification and treatment of infectious uveitis is emphasized. Early identification can be achieved with a combination of maintaining a high suspicion, recognizing certain clinical features, utilizing multi-modal imaging, and obtaining specimens for molecular diagnostic testing.

Chikungunya fever. Rheumatic manifestations of an emerging disease in Europe

Chikungunya fever is a viral disease caused by an alphavirus belonging to the Togaviridae family, transmitted by several species of Aedes mosquitoes: Aedes aegypti and Aedes albopictus (A. albopictus). It is endemic in Africa and Asia with recurrent outbreaks. It is an emerging disease and cases in Europe transmitted by A. albopictus have been established in Mediterranean areas. The first autochthonous cases detected on the Caribbean islands suppose a serious threat of spreading disease to America, which so far has been disease free. Clinical symptoms begin abruptly with fever, skin rash and polyarthritis. Although mortality is low, a high percentage of patients develop a chronic phase defined by persistent arthritis for months or even years. A severe immune response is responsible for joint inflammation. The absence of specific treatment and lack of vaccine requires detailed studies about its immunopathogenesis in order to determine the most appropriate target.

Ocular manifestations of emerging infectious diseases

PURPOSE OF REVIEW

Emergent and resurgent infectious diseases are major causes of systemic morbidity and death that are expanding worldwide mainly because of climate changes and globalization. Among them, specific diseases have been recently associated with ocular involvement. This review presents the ocular manifestations of selected emerging infectious diseases relevant to the ophthalmologist.

RECENT FINDINGS

An array of ocular manifestations, involving mainly the posterior segment, have been recently described in association with specific arthropod vector-borne diseases including rickettsioses, West Nile virus, Rift Valley fever, Dengue fever, and Chikungunya. Influenza A (H1N1) virus has also been recently associated with ocular involvement. On the contrary, with advances in laboratory testing applied to ocular fluids, new infectious agents, mainly viruses, are increasingly being found to be associated with uveitis.

SUMMARY

Emerging infectious diseases should be considered in the differential diagnosis of retinitis, chorioretinitis, retinal vasculitis, optic neuropathy, or any other ocular inflammatory condition in a patient living in or traveling back from a specific endemic area. On the contrary, ocular fluid sampling and analysis for specific new pathogens can be recommended in selected patients with uveitis of unexplained cause.