Epidemic Retinitis

Systemic and Ophthalmic Manifestations of Chikungunya Fever

PURPOSE

Chikungunya is a re-emerging viral infection across the globe. The purpose of this article is to review the systemic and ophthalmic manifestations associated with chikungunya fever.

METHOD

A review of literature was conducted using online databases.

RESULTS

In this report, we have reviewed the presently available literature on uveitis caused by chikungunya and highlighted the current knowledge of its clinical manifestations, imaging features, laboratory diagnostics, and the available therapeutic modalities from the systemic and ophthalmic standpoint.

CONCLUSIONS

Ocular involvement in chikungunya infection may occur at the time of systemic manifestations or it may occur as a delayed presentation many weeks after the fever. Treatment relies on a supportive therapy for systemic illness. Treatment of ocular manifestation depends on the type of manifestations and usually includes a combination of topical and oral steroids.

Sea-fan retinal neovascularization associated with rickettsial retinitis: a case report

BACKGROUND

Rickettsial disease has been commonly associated with retinitis, retinal vasculitis, and optic nerve involvement, but the development of retinal neovascularization has been very rarely reported. We herein describe a case of rickettsial retinitis complicated with the development of sea-fan retinal neovascularization documented with multimodal imaging, including fundus photography, SS-OCT, fluorescein angiography, and SS-OCT angiography.

CASE PRESENTATION

A 26-year-old female with a history of fever one week earlier presented with sudden decreased vision in the left eye. Best-corrected visual acuity (BCVA) was 20/2000 and the patient was diagnosed with rickettsial retinitis along the superotemporal retinal vascular arcade associated with serous retinal detachment and retinal hard exudates. The indirect immunofluorescence test was positive for Rickettsia conorii, and the patient was treated with oral doxycycline (200 mg/day) and oral prednisone (0.75 mg/kg/day, with gradual tapering). Four weeks after presentation, the retinal infiltrate and associated serous retinal detachment had resolved, but retinal hard exudates had increased. A large sea-fan preretinal fibrovascular neovascularization became apparent along the superotemporal retinal vascular arcade, but there was no associated retinal ischemia on fluorescein angiography. The patient received an adjunctive single intravitreal injection of 1.25 bevacizumab. Sequential follow-up examinations showed shrinking of sea-fan retinal neovascularization, a complete resolution of retinal hard exudates, and the development of a self-limited vitreous hemorrhage. On last follow-up, 30 months after intravitreal bevacizumab injection, BCVA was 20/25.

CONCLUSION

Patients with rickettsial retinitis may develop a sea-fan retinal neovascularization, with subsequent vitreous hemorrhage, putatively through inflammatory mechanisms. Multimodal imaging including OCT, fluorescein angiography, and OCT-angiography, is highly useful for accurate diagnosis and reliable monitoring of the evolution of retinitis, retinal neovascularization, and other retinal changes. The use of a combination therapy with oral doxycycline and corticosteroids and intravitreal anti-VEGF can improve outcomes.

Treatment Outcomes of Presumed Rickettsial Retinitis: Evidence from OCTA Based Quantitative Analysis

AIM

To quantify retinal ischemia following presumed rickettsial retinitis (RR). To compare outcomes between initial treatment with Doxycycline (Group 1) versus steroids (Group 2).

METHODS

Retrospective analysis of patients with presumed RR was done. ImageJ software was used to obtain %area of ischemia on swept-source optical coherence tomography angiography (SS-OCTA).

RESULTS

Eleven eyes of 8 patients belonged to Group1 and 6 eyes of 3 patients belonged to Group 2. The BCVA improved from logMAR 0.8 ∓ 0.7 to logMAR 0.06 ∓ 0.08 (p < 0.002) and central foveal thickness (CFT) changed from 479μ ∓ 341.3μ to 163.5μ ∓ 20.5μ (p < 0.005) after a median of 5 weeks in Group 1. In Group 2, BCVA improved from logMAR 1.03 ∓ 0.05 to logMAR 0.23 ∓ 0.23 (p < 0.004) and CFT changed from 286.5μ ∓ 158.8μ to 177.5μ ∓ 25.9μ (>0.05) following a mean of 11 weeks. Mean %area of ischemia was 4.6 ∓ 1.5 in Group 1 and 13.9 ∓ 4.1 in Group 2.

CONCLUSION

Analysis of flow deficit on SS-OCTA confirms that treatment with Doxycycline in presumed RR results in less ischemia and quicker recovery than initial treatment with steroids.

Choroidal and central macular thickness before and after treatment in post fever retinitis

PURPOSE

To study the choroidal thickness (CT) and central macular thickness (CMT) in post-fever retinitis (PFR) and their correlation with visual acuity and treatment.

METHODS

A retrospective, observational study of patients presenting with PFR from 2013 to 2021 and with spectral domain optical coherence tomography (SD-OCT) (Heidelberg®, SpectralisTM, Heidelberg, Germany) images were included. The CT and CMT were measured at presentation and at the final visit. The CT was measured subfoveally and at points 2000 µm superior, inferior, medial, and lateral from the fovea using the caliper tool.

RESULTS

Seventy-nine eyes of 65 patients were included for this study. The mean age was 39.03 (±16.00) years with female preponderance of 53.84% (n = 35). Mean follow-up duration was 30 days. Mean CT at presentation and at follow-up was 254.12 µm and 241.51 µm, respectively. CT was decreased in majority of the eyes 67.1% (n = 53) from their baseline value. Mean CMTs at presentation and final visit were 454.8 µm and 223.7 µm, respectively. Best corrected visual acuity had a positive correlation with CMT (r = 0.340; P = 0.002) and negligible correlation with CT. A significant decrease in the mean CT was noted in patients who received doxycycline either alone or in combination with a steroid as compared to those who did not receive any treatment (P < 0.001). The significance of which is unknown presently.

CONCLUSION

CMT has a greater role in determining the final visual outcome than CT. CT can be reduced post-treatment with no effect on vision.

Bilateral retinal vasculitis due to presumed sarcoidosis with rickettsial retinitis

OBJECTIVE

To describe a case of bilateral retinal vasculitis due to presumed sarcoidosis and rickettsial retinitis complicated with neovascularization with tear biomarker analysis.

METHODS

A retrospective case report.

RESULTS

A 16-year-old male presented with bilateral retinal vasculitis and retinitis in both eyes with inferotemporal quadrant neovascularization in the right eye. Multimodal imaging revealed the presence of active inflammation in both eyes. Weil Felix test was positive with raised ACE levels. This patient was treated with local and systemic steroids, doxycycline, and laser photocoagulation followed by oral methotrexate therapy which resulted in clinical resolution with recovery of visual acuity. Tear biomarker analysis showed raised sICAM-1 and MMP-9 levels in both eyes which significantly reduced following treatment.

CONCLUSION

Ocular sarcoidosis with rickettsial infection is a rare association. Tear biomarkers correlated well with clinical and imaging manifestations. High index of suspicion and aggressive anti-inflammatory therapy can help control inflammation and restore good vision.

Post-fever Retinitis With a Positive Weil-Felix Test: A Study From a Tertiary Center in South India

Background Post-fever retinitis (PFR) is reported two to six weeks after fever and affects one or both eyes. Rickettsial fever is one of the most common causes of PFR. This study aimed to report the clinical features and treatment outcomes of PFR cases with a positive Weil-Felix test. Methodology In this study, we collected demographic data, fever details, eye symptoms, ocular examination findings, optical coherence tomography (OCT) and fundus fluorescein angiography findings, laboratory findings, and length of follow-up of consecutive PFR cases with a positive Weil-Felix test. All cases were treated with oral doxycycline and prednisolone. Final best-corrected visual acuity (BCVA) and ocular examination findings were recorded. Visual field examination and follow-up OCT results were noted if available. Results A total of nine patients (eight males) with a mean age of 39.1 years with fever before ocular symptoms and positive Weil-Felix test were included. Six patients had bilateral disease. The mean initial and final BCVA in the affected eyes was 1.16 and 0.35 logMAR units, respectively (p < 0001). All 15 eyes had typical white retinitis patches and retinal hemorrhages which resolved after treatment. OCT showed hyperreflectivity and inner retinal disorganization over retinitis patches. White subretinal lines were noted in three patients and retinal nerve fiber bundle defect with corresponding visual field defect was seen in one eye. Conclusions In this study, PFR due to rickettsia infections has been reported from our region for the first time. Hence, eye specialists in the region should be aware of this entity.

Emerging Pathogenic Viral Infections of the Eye

Global health security threats and the public health impact resulting from emerging infectious diseases including the ongoing COVID-19 pandemic and recent Ebola virus disease outbreaks continuously emphasize the need for a comprehensive approach to preparedness, management of disease outbreaks, and health sequelae associated with emergent pathogens. A spectrum of associated ophthalmic manifestations, along with the potential persistence of emerging viral pathogens in ocular tissues, highlight the importance of an ophthalmic approach to contributing to efforts in the response to public health emergencies from disease outbreaks. This article summarizes the ophthalmic and systemic findings, epidemiology, and therapeutics for emerging viral pathogens identified by the World Health Organization as high-priority pathogens with epidemic potential.

Visual Fields in Epidemic Retinitis

AIM

The aim of the study is to analyze visual fields defects (VFDs) in epidemic retinitis (ER).

METHODS

Patients with ER and Humphrey's visual field (HFA) 30-2 performed after resolution were studied. VFD severity grading was performed. Patients treated with oral doxycycline (Group-A) versus doxycycline-steroids (group-B) were compared.

RESULTS

Thirty-five eyes of 25 patients were studied. Nasal, inferior, temporal and central VFD were seen in 19 (54.2%), 13 (37.1%), 7 (20%) and 6 (17.1%) eyes, respectively. Grade 0, 1, 2 and 3 VFDs were seen in 4 (11.4%), 15 (42.8%), 12 (34.2%) and 4 (11.4%) eyes respectively. Seven eyes with ≥1 year of follow-up post-resolution also showed grade 0-3 scotomas. Mean severity of scotoma was grade 1.15 (Median: 1) and 1.42 (Median: 1.5) in groups A (n = 13) and B (n = 14), respectively (p = .637).

CONCLUSION

ER can cause VFD persisting long after resolution. Treatment with oral doxycycline without steroids was non-inferior to combined treatment with respect to VFD.

Epidemic retinitis during the COVID-19 pandemic

Purpose

To study the impact of the novel coronavirus disease-2019 (COVID-19) pandemic on incidence, seasonal variation, clinical presentation, and disease outcome of epidemic retinitis (ER) and to compare clinical outcomes with positive and negative COVID-19 serology.

Methods

This is a retrospective, observational study conducted at a tertiary eye care hospital from August 2020 to June 2022. A graph of ER cases against the month of presentation was compared with the graph of the COVID-19 pandemic in the same region. Cases presented before COVID-19 vaccination, with positive COVID-19 serology (Group 1) were compared with cases with negative serology (Group 2).

Results

One hundred and thirty-two cases of ER were seen. The least number of cases were seen during and immediately after the peak of the pandemic (May 2021-August 2021). COVID-19 serology was positive in 13 (22 eyes)/60 (21.6%) unvaccinated cases. Along with COVID-19, positive serology for other ER etiologies was seen in 5/13 cases (38.4%). All patients received oral doxycycline with/without steroids. Groups 1 and 2 included 22 and 21 eyes of 13 cases each. Macular edema resolved in 43.6 and 32 days in groups 1 and 2, respectively. Retinitis resolved at 1 month in both groups. Corrected distant visual acuity was 20/50 and 20/70 at the presentation, which improved to 20/20 and 20/25 in groups 1 and 2, respectively. Mean and median follow-up was 6 months and 4.5 months, respectively, in both groups. No complications or recurrences were seen.

Conclusion

No significant impact of the COVID-19 pandemic on ER was observed.

Epidemic retinitis during pregnancy

Purpose

To study the clinical presentation and treatment outcome of epidemic retinitis (ER) during pregnancy.

Methods

This is a retrospective, observational chart review of pregnant patients diagnosed with ER from January 2014 to February 2023. Demographic details, month of pregnancy at the onset of ocular symptoms, history of present illness, clinical manifestations, and treatment outcomes were studied.

Results

In 9 years, ER was seen in 86 females, of whom 12 (13.9%) were pregnant. Twenty-one eyes of those 12 patients were studied. Most of the patients presented in the sixth month of pregnancy (range: 5-9 months, mean: 6.3 months). Physicians diagnosed viral exanthematous fever in six, typhoid in three, and suspected rickettsia in one patient. Medical termination of pregnancy (MTP) was performed in two patients before presentation. Weil-Felix test was positive in five, Brucella in one, WIDAL in three, and coronavirus disease 2019 (COVID-19) IgG and dengue IgG in one patient each. Oral antibiotics were given in five patients (two post-medical termination of pregnancy [MTP]) for the retinitis. All except four received oral steroids. Mean presenting corrected distant visual acuity (n = 21) was 20/125 (range: 20/20-20/20,000), which improved to (n = 18) 20/30 (range: 20/20-20/240). Macular edema (n = 11) resolved in 33.18 days (range: 20-50 days), and retinitis (n = 13) resolved in 58 days (range: 30-110 days). Ocular and systemic examination of newborn was possible in two and the babies were normal.

Conclusion

ER is seen commonly at the beginning of the third trimester. Lack of antibiotics may delay the resolution of retinitis. Ocular health needs to be assessed in larger series to conclude absence of retinal involvement in newborns.

Dengue Virus Infection of Human Retinal Müller Glial Cells

Retinopathy is a recently recognized complication of dengue, affecting up to 10% of hospitalized patients. Research on the pathogenesis has focused largely on effects of dengue virus (DENV) at the blood-retinal barrier. Involvement of retinal Müller glial cells has received little attention, although this cell population contributes to the pathology of other intraocular infections. The goal of our work was to establish the susceptibility of Müller cells to infection with DENV and to identify characteristics of the cellular antiviral, inflammatory, and immunomodulatory responses to DENV infection in vitro. Primary human Müller cell isolates and the MIO-M1 human Müller cell line were infected with the laboratory-adapted Mon601 strain and DENV serotype 1 and 2 field isolates, and cell-DENV interactions were investigated by immunolabelling and quantitative real-time polymerase chain reaction. Müller cells were susceptible to DENV infection, but experiments involving primary cell isolates indicated inter-individual variation. Viral infection induced an inflammatory response (including tumour necrosis factor-α, interleukin [IL]-1β, and IL-6) and an immunomodulatory response (including programmed death-ligand [PD-L]1 and PD-L2). The type I interferon response was muted in the Müller cell line compared to primary cell isolates. The highest infectivity and cell responses were observed in the laboratory-adapted strain, and overall, infectivity and cell responses were stronger in DENV2 strains. This work demonstrates that Müller cells mount an antiviral and immune response to DENV infection, and that this response varies across cell isolates and DENV strain. The research provides a direction for future efforts to understand the role of human retinal Müller glial cells in dengue retinopathy.

Case Report: Optic neuritis as the initial presentation of Orientia tsutsugamushi infection detected by metagenomic next-generation sequencing

Scrub typhus is an acute febrile illness caused by Orientia tsutsugamushi infection, and typically manifested as fever, eschar, lymphadenopathy, rash, and other flu-like signs. Ocular involvement was not uncommon, and mostly occurred at post-fever or recovery stage in scrub typhus cases. We hereby report a case of scrub typhus presenting as unilateral optic neuritis (ON). A 56-year-old man going wild fishing nearly every day complained of a blurred vision and an inferior visual field defect in the right eye two or three days after an insect-bite like shin induration in his left leg. He was diagnosed as ON, and treated with dexamethasone in the local hospital. Unfortunately, his right eye vision progressively deteriorated during steroid therapy. Three days after steroid therapy ceased, he suffered from a high fever and painful subcutaneous masses in the left groin. Peripheral blood test by metagenomic next-generation sequencing (mNGS) was positive for Orientia tsutsugamushi, but negative for other pathogens. The diagnosis was then revised to scrub typhus and ON. His systemic symptoms rapidly disappeared after oral doxycycline and omadacycline therapy. However, his right eye vision continuously deteriorated to hand motion. Further serum tests for aquaporin 4-IgG antibody and myelin oligodendrocyte glycoprotein-IgG antibody were both negative, but for anticardiolipin IgM and beta-2-glycoprotein-I IgM were both positive. The patient's right eye vision gradually improved after doxycycline combined with steroid pulse therapy. Our case indicates that ON in scrub typhus cases may present as a parainfectious inflammation, and that mNGS is a useful and valuable method for early diagnosis of scrub typhus.

Stepwise approach for fundus imaging in the diagnosis and management of posterior uveitis

An array of retinochoroid imaging modalities aid in comprehensive evaluation of the immunopathological changes in the retina and choroid, forming the core component for the diagnosis and management of inflammatory disorders such as uveitis. The recent technological breakthroughs have led to the development of imaging platforms that can evaluate the layers of retina and choroid and the structural and functional alteration in these tissues. Ophthalmologists heavily rely on imaging modalities such as dye-based angiographies (fluorescein angiography and indocyanine green angiography), optical coherence tomography, fundus autofluorescence, as well as dye-less angiography such as optical coherence tomography angiograph,y for establishing a precise diagnosis and understanding the pathophysiology of the diseases. Furthermore, these tools are now being deployed with a 'multimodal' approach for swift and accurate diagnosis. In this comprehensive review, we outline the imaging platforms used for evaluation of posterior uveitis and discuss the organized, algorithmic approach for the assessment of the disorders. Additionally, we provide an insight into disease-specific characteristic pathological changes and the established strategies to rule out disorders with overlapping features on imaging.

Bilateral macular retinitis in patients with presumed rift valley fever from Sudan: A case series

BACKGROUND

Epidemic retinitis occurs seasonally following febrile infections in endemic regions. Rift valley fever (RVF) is endemic to Sudan, with a recent outbreak starting in 2019.

METHODS

Retrospective case series of 3 patients travelling from Sudan with post-febrile retinitis, and with a history and clinical picture suggestive of RVF retinitis.

RESULTS

The three patients were adult males with underlying medical conditions and underwent fundus fluorescein angiography that confirmed bilateral retinitis and occlusive vasculitis involving the posterior pole. Optical coherence tomography showed distortion of the macular layers. Case 2 presented 1 month following febrile illness and had retinal thinning, with optical coherence tomography angiography showing marked reduction in vessel density.

CONCLUSION

We present multimodal imaging data of three cases with presumed RVF retinitis from a recent outbreak in Sudan. The unavailability of standardized methods of testing for RVF, as is the case for most epidemic retinitis-causing pathogens, makes the diagnosis challenging.

Bilateral Post Fever Retinitis With Retinal Vascular Occlusions Following Severe Acute Respiratory Syndrome Corona Virus (SARS-CoV2) Infection

INTRODUCTION

As the world fights the pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), several reports of retinal manifestations of the disease are emerging. Post fever retinitis is a well reported ocular inflammatory reaction to multiple invasive agents, be it virus, bacteria or other microbial agent.

PURPOSE

We report an interesting case of bilateral multifocal retinitis with multiple vascular occlusions in a patient, three weeks after a febrile illness.

RESULTS

Investigations to ascertain the cause of fever resulted in identifying ephemeral seropositivity for several different Ribonucleic acid (RNA) viruses. The retinitis was managed with systemic steroids, doxycycline and anticoagulants with improvement in vision.

CONCLUSION

High and persistent seropositive response against (SARS-CoV-2) helped us to narrow it as the causative agent but the cross reactivity of SARS-CoV-2 with other viruses can be misleading and needs careful interpretation.

Epidemic Retinitis with Positive or Negative Weil Felix Test - a Comparative Study and Outcome with Doxycycline

PURPOSE

To compare clinical manifestations and disease outcomes in Epidemic Retinitis (ER) with positive or negative Weil Felix Test (WFT).

METHODS

Retrospective, observational, comparative study. WFT positive or negative patients formed Group 1 and 2, respectively. Patients receiving oral doxycycline monotherapy formed subgroup A and B. Duration of resolution of macular edema and retinitis was compared.

RESULTS

Novel finding of "ring retinitis" was observed equally in group 1 and 2. Complete resolution of macular edema took 41.3 days (range: 30-60 days) and 43.68 days (range: 20-105 days) (p = .668) and retinitis lesions resolved in 34.3 days (range: 14-65 days) and 34 days (range: 12-60 days) (p = .875) in group A and B, respectively. All (n = 14) eyes with retinitis within 1 disc diameter of fovea improved better than 20/80 except 1.

CONCLUSION

No significant difference with respect to clinical, imaging findings and the treatment outcome was observed in WFT positive or negative cases.

Presumed Post COVID- Infection Retinitis – Clinical and Tomographic Features of Retinitis as a Post-COVID Syndrome

PURPOSE

To study clinical and imaging features of presumed post-COVID infection retinitis.

METHOD

Retrospective case series of patients presenting with retinitis lesions with evidence of recent COVID infection. Retinal findings and optical coherence tomography (OCT) features were studied at baseline and follow-ups.

RESULTS

Twenty-four eyes of 17 patients were included. Mean age was 36.57 ± 11.78 years. Baseline visual acuity (VA) was log MAR 0.97 ± 0.43. Fundus findings included retinitis patches (n = 24),hard exudates (n = 8), and superficial hemorrhages (n = 16). OCT features included neurosensory detachment (NSD, n = 20), hyperreflective inner layers (n = 24), acute macular neuroretinopathy (AMN, n = 8), hyperreflective foci (n = 20). At final follow-up, VA was logMAR 0.43 ± 0.27. Retinitis patches persisted in four eyes, AMN in three eyes, and NSD in five eyes. Conclusion- Post- COVID infection retinitis adds to existing literature on post COVID syndromes.

Ocular Manifestations of Chikungunya Infection: A Systematic Review

The Chikungunya virus (CHIKV) can cause long lasting symptoms and manifestations. However, there is little information on which ocular ones are most frequent following infection. We performed a systematic review (registered in the International Prospective Register of Systematic Reviews; no CRD42020171928) to establish the most frequent ocular manifestations of CHIKV infection and their associations with gender and age. Articles published until September 2020 were selected from PubMed, Scielo, Cochrane and Scopus databases. Only studies with CHIKV-infected patients and eye alterations were included. Reviews, descriptive studies, or those not investigating the human ocular manifestations of CHIKV, those with patients with other diseases and infections, abstracts and studies without relevant data were excluded. Twenty-five studies were selected for inclusion. Their risk of bias was evaluated by a modified Newcastle-Ottawa scale. The most frequent ocular symptoms of CHIKV infection included ocular pain, inflammation and reduced visual acuity, whilst conjunctivitis and optic neuritis were the most common manifestations of the disease. These occurred mostly in individuals of 42 ± 9.5 years of age and woman. The few available reports on CHIKV-induced eye manifestations highlight the need for further research in the field to gather more substantial evidence linking CHIKV infection, the eye and age/gender. Nonetheless, the data emphasizes that ocular alterations are meaningful occurrences of CHIKV infection which can substantially affect quality of life.

Epidemic retinitis - Factors associated with poor visual outcomes

Purpose:

To identify factors other than macular edema and retinitis location responsible for poor visual outcomes in epidemic retinitis (ER).

Methods:

A retrospective, observational, comparative study. Eyes with corrected distant visual acuity (CDVA) 20/200 or worse at resolution formed Group A. Eyes with central macular thickness (CMT) 600 μm or worse and retinitis within 1500 μm to foveal center at the presentation, but improved to CDVA 20/200 or better at the resolution formed Group B. The patient’s history, clinical presentation, imaging, and treatment outcomes were studied and the factors responsible for the final visual outcomes were compared in both groups.

Results:

Groups A and B included 25 eyes each. The mean CDVA at the presentation was 20/400 (range: 20/125–20000) and 20/320 (range: 20/80–20000), and mean CMT at the presentation was 948.5 μm (range: 520–1553) and 912.2 μm (range: 615–1250) in Groups A and B, respectively. All eyes except 1 (Group A) had retinitis lesions within 1500 μm of foveal center. The mean CDVA at the resolution was 20/400 (range: 20/200–20/20000) and 20/40 (range: 20/20–20/80) in Groups A and B, respectively. Older age, male gender, diabetic status, delayed presentation, poor presenting CDVA, bilaterality, presence of keratic precipitates, disk pallor, retinal thinning, and subfoveal deposits had a statistically significant association, whereas the absence of skin rash, ellipsoid zone loss, negative WIDAL, Weil-Felix test, and delayed doxycycline therapy or use of steroids without doxycycline had a statistically insignificant association with poor visual outcomes.

Conclusion:

Apart from presenting CMT and location of retinitis, multiple demographic, clinical, and imaging factors can be implicated for poor visual outcomes.

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.

Predictors of visual outcome in post-fever retinitis: a retrospective analysis

PURPOSE

To identify the predictors of final visual outcome in cases with post-fever retinitis (PFR).

METHODS

This is a retrospective study of cases with diagnosis of post-fever retinitis. Colour fundus photograph and optical coherence tomography (OCT) parameters at presentation and final visit were analysed. Various factors at presentation [age, systemic illness, best-corrected visual acuity (BCVA), area of retinitis and hard exudates, OCT parameters], at final visit (OCT parameters) and the treatment modalities used were correlated with BCVA at final visit.

RESULTS

Twenty-four eyes of 16 patients with PFR were included in the study. Median BCVA at presentation was 6/60 and at final visit was 6/9. By multiple linear regression after adjusting for other variables, for every 1 unit increase in height of subretinal fluid (SRF) at fovea at presentation, the value of final BCVA decreased by 0.001 unit. For every 1 unit increase in extent of ellipsoid zone (EZ) loss and subfoveal deposit height, the value of final BCVA decreased by 0.0001 unit and 0.004 unit, respectively. The baseline OCT parameters that had negative correlation with final BCVA included central macular thickness (r: - 0.5182, p: 0.02), maximum SRF height (r: - 0.5539, p < 0.01) and SRF height at fovea (r: - 0.582, p < 0.01). The OCT parameters at final visit which had a negative correlation with final BCVA included disorganisation of retinal inner layers (DRIL) within 1000 microns from centre of fovea (r: - 0.6494, p < 0.01), height of subfoveal deposit (r: - 0.7627, p < 0.01), horizontal extent of subfoveal deposit (r: - 0.6695, p < 0.01) and extent of EZ loss (r: - 0.8216, p < 0.01).

CONCLUSION

Height of SRF at presentation, extent of EZ loss and subfoveal deposit height at final visit were associated with poor final BCVA in PFR.

Clinical profile and response to steroids in post-fever retinitis: a nine-year experience from a referral institute in the rural hinterland of Central India

PURPOSE

To describe the demographics, clinical features, and treatment outcomes with systemic steroids in eyes presenting with post-fever retinitis (PFR) from Central India.

METHODS

Single-center, retrospective analysis of 147 eyes of 98 PFR cases between 2011 and 2019.

RESULTS

Mean age of the study cohort was 33.46 ± 12.76 years, with 72 males and 26 females. The mean interval between the onset of fever and the diminution of vision was 21.10 ± 13.54 days (range 0-60 days). The number of PFR cases increased over the nine years with 89 cases (90.1%) presenting during winters. Unilateral involvement was seen in 49 cases, while 49 had bilateral involvement. Clinical characteristics included: multifocal retinitis (n = 122; 61.2%), hemorrhages (n = 132; 89.8%), disc edema (n = 57; 38.8%), anterior chamber reaction (n = 28; 19%), and vitritis (n = 103; 70.1%). Treatment included intravenous followed by oral steroids in 70 patients and oral steroids exclusively in 23; five patients denied treatment. The visual acuity improved from 1.09 ± 0.52 LogMAR to 0.29 ± 0.42 LogMAR (p < 0.05).

CONCLUSION

There has been an increase in the prevalence of PFR cases over the last decade with clustering during the winters. Multifocal retinitis, retinal hemorrhages, and vitritis were the most common clinical findings in our series. The retinitis resolved with improvement in vision following steroid therapy in all eyes.

Role of multicolour imaging in post-fever retinitis involving posterior pole

PURPOSE

To describe composite multicolour (MC) imaging features along with the monocoloured fundus reflectance images in active and resolving stages of post-fever retinitis (PFR).

METHODS

Retrospective image analysis of cases of PFR who underwent dilated retinal clinical examination followed by optical coherence tomography and MC imaging.

RESULTS

Twenty-five eyes of 18 patients diagnosed with PFR were included. There were 11 males and 7 females. Mean age of patients was 30.63 years. The retinitis lesion appeared bright white on MC image and white mainly on blue and green reflectance images during the active stages of PFR. The lesion appeared dull-grey to greyish white during the resolving stages and as dull-green in resolved cases. The active stages showed the presence of intraretinal/subretinal fluid which appeared as green colour on MC images and less green to normal during resolving stages. Hard exudates were seen as bright yellow- or orange-coloured spots on MC image during the resolving stages of the disease.

CONCLUSION

The different stages of PFR show different colour on multicolour image and different reflectance patterns on individual colour reflectance channels. Hence, multimodal fundus imaging with different wavelength can be helpful for differentiation of activity in PFR.

Severe ocular and adnexal complications in dengue hemorrhagic fever: A report of 29 eyes

Purpose:

To describe a series of sight-threatening ocular and adnexal involvement associated with dengue hemorrhagic fever and their treatment options.

Methods:

Retrospective, interventional, non-comparative case series. Medical records of patients who presented with ocular symptoms attributed to dengue hemorrhagic fever were reviewed. Demography, presenting features, and treatment outcomes were recorded. Outcome measures assessed included globe salvage, vision salvage, and visual improvement. The outcome was deemed as favorable if vision salvage was possible and unfavorable if the vision was lost.

Results:

Twenty-nine eyes of 23 patients were included. Bilateral ocular involvement was seen in 6 (26%) patients. The mean age was 37.62 ± 18.68 years (range: 14 to 81 years). Coexistent diabetes mellitus and enteric fever were present in three patients. History of blood transfusion was present in nine (40%) and thrombocytopenia in eight (35%) patients at the time of presentation with ocular complaints. Presenting features included endophthalmitis in 11 (38%), panophthalmitis in 10 (35%), orbital cellulitis with panophthalmitis in four (14%), isolated corneal or scleral melt in three (10%), and orbital hemorrhage with panophthalmitis in one (3%) patient. Globe salvage was achieved in 21/29 eyes (72.4%), vision salvage in 6/29 eyes (20.68%), and improvement in visual acuity was noted in 5/29 eyes (17.24%). Logistic regression analysis revealed no significant effect of any clinical-microbiological factors on globe salvage, vision salvage, and visual improvement. However, visual improvement and globe salvage were possible in eyes that underwent early endoscopic vitrectomy.

Conclusion:

Dengue fever can present with sight-threatening ocular and adnexal inflammation resulting in endophthalmitis and panophthalmitis, orbital cellulitis, corneal and scleral melt, and orbital hemorrhage. Early vitrectomy may improve vision and globe salvage in cases with significant vitritis.

Epidemic retinitis and community outbreaks

Purpose:

The objective of this study was to correlate seasonal variation of epidemic retinitis (ER) with concurrent community outbreaks.

Methods:

This is a retrospective, observational, comparative study conducted in a tertiary care eye hospital in south India. Monthly variation in number of ER cases in comparison with reported community outbreaks by Integrated Disease Surveillance Program (IDSP) from 2009 to 2020 in the same region were studied. Month-wise graphs against number of patients were plotted for ER and for each community outbreak.

Results:

ER was diagnosed in 163 patients. Diagnosis of presumed rickettsial ER was made in 48 cases (29.44%), chikungunya in 5, dengue in 3 and typhoid in 6 cases, while in other cases the etiological diagnosis remained uncertain (n = 101). Multiple positive serological tests were seen in 6 patients (Weil Felix Test (WFT) with WIDAL in 4 and chikungunya IgM with WFT in 2 patients). Relevant reported outbreaks by IDSP were: Pyrexia of unknown origin (PUO) (n = 5148), Chikungunya (n = 6577), Dengue (n = 7350), Measles (n = 1422), Mumps (n = 881), Rubella (n = 288), Malaria (n = 2262), Chicken Pox (n = 2385), Typhoid (n = 597), Kyasanur Forest Disease (n = 381), Scrub Typhus (n = 13), Typhus fever (n = 4), Japanese Encephalitis (n = 15). None of the outbreak graphs pattern was identical or similar to the graph of ER. Inverse relation of the graph of dengue outbreak with ER was observed.

Conclusion:

Inverse correlation between dengue and ER should be further studied for causation, which we believe may prove dengue as least common cause. Reporting of rickettsial outbreaks should be enhanced by undertaking statewide awareness and procurement of gold standard tests.

Microbes of the human eye: Microbiome, antimicrobial resistance and biofilm formation

BACKGROUND

The review focuses on the bacteria associated with the human eye using the dual approach of detecting cultivable bacteria and the total microbiome using next generation sequencing. The purpose of this review was to highlight the connection between antimicrobial resistance and biofilm formation in ocular bacteria.

METHODS

Pubmed was used as the source to catalogue culturable bacteria and ocular microbiomes associated with the normal eyes and those with ocular diseases, to ascertain the emergence of anti-microbial resistance with special reference to biofilm formation.

RESULTS

This review highlights the genetic strategies used by microorganisms to evade the lethal effects of anti-microbial agents by tracing the connections between candidate genes and biofilm formation.

CONCLUSION

The eye has its own microbiome which needs to be extensively studied under different physiological conditions; data on eye microbiomes of people from different ethnicities, geographical regions etc. are also needed to understand how these microbiomes affect ocular health.

Clinical features, optical coherence tomography findings and treatment outcomes of post-fever retinitis

Objectives:

To study the clinical features, optical coherence tomography (OCT) findings, treatment options and follow-up outcomes of post-fever retinitis (PFR).

Subjects:

A total of 19 eyes of 13 patients, diagnosed with PFR (retinitis following febrile episode) over 2 years were retrospectively studied.

Methods:

Documented history, baseline clinical features and systemic investigations performed for PFR were reviewed. Fundus findings, foveal architecture on swept-source OCT, the treatment options and the follow-up outcomes including best-corrected visual acuity (BCVA) and central foveal thickness (CFT) were reviewed and analyzed.

Results:

Common fundus findings included whitish retinitis lesions (100%), macular star (95%, 18eyes), retinal flame-shaped hemorrhages (63%, 12 eyes), inflammatory retinal vessels (30%, 6 eyes), vitreous hemorrhage (one eye) and OCT findings included neuro-sensory detachment (79%, 15 eyes), intraretinal white dots (89.5%,17 eyes). The baseline median log MAR BCVA and CFT were 1.30 (interquartile range (IQR):0.8–1.8) and 423 microns (IQR:182–555). Overall, nine patients (12 eyes) received a combination of oral doxycycline and oral steroids and four patients (7 eyes) received a combination of oral doxycycline, oral steroid and intravitreal anti-vascular endothelial growth factor (IVA). Significant improvement was evident at 8 weeks in median BCVA (0.50, IQR: 0.3–0.8, p < 0.05) and median CFT (223 micron, IQR: 170–256, p < 0.05) though only 26% (5 eyes) attained BCVA > = 6/12.

Conclusion:

Our study puts forth certain characteristic fundus and OCT features of PFR. A combination of oral doxycycline and oral steroids as a treatment option showed improvement in BCVA and CFT. Additional IVA helps in faster visual recovery in patients presenting with severe macular edema at onset.

Mycobiome changes in the vitreous of post fever retinitis patients

Fungi have been associated with various diseases of the eye like keratitis, uveitis and endophthalmitis. Despite this fact, fungal microbiome (mycobiome) studies compared to the bacterial microbiome studies have remained neglected. In the present study, using metagenomic sequencing, the mycobiomes of the vitreous of healthy control individuals (VC, n = 15) and individuals with post fever retinitis + non-PFR uveitis (PFR+, n = 9) were analysed and compared. The results indicated that Ascomycota was the most predominant phylum in both VC and PFR+ groups. Further, at the genera level it was observed that the abundance of 17 fungal genera were significantly different in post fever retinitis (PFR, n = 6) group compared to control group. Of these 17 genera, it was observed that 14 genera were relatively more abundant in PFR group and the remaining 3 genera in the VC group. Genus Saccharomyces, a commensal of the gut and skin, was predominantly present in the vitreous of both the cohorts, however it was significantly less abundant in PFR group. Further, significant increase in the genera that have a pathogenic interaction with the host were observed in PFR group. On the whole the mycobiome in both the groups differed significantly and formed two distinct clusters in the heatmap and Principal co-ordinate analysis. These results demonstrate significant changes in the mycobiome from the vitreous of post fever retinitis patients compared to healthy controls thus implying that dysbiotic changes in the fungal vitreous microbiome are associated with PFR.

Three-years follow-up swept source optical coherence tomography angiography findings in post-fever retinitis

Post fever retinitis (PFR), characterized by multiple cotton wool spot like lesions in the posterior pole, is commonly reported following viral and bacterial infections. Retinal perfusion defects have been documented with the help of optical coherence tomography angiography (OCTA) in cases of PFR. But long term changes in such cases have not been reported earlier. In the following report, we have described the swept-source OCTA findings of two PFR patients at initial presentation and three years follow-up. Initial OCTA scans may not provide accurate information regarding the perfusion status due to associated retinal edema and inflammation. However, persisting perfusion defects at the superficial and deep retinal capillary plexus were noted on long term follow-up in both the cases.

Post-fever retinitis - Newer concepts

Post-fever retinitis (PFR) is an infectious or para-infectious uveitic entity caused by bacterial or viral agents and seen mainly in tropical countries. Systemic symptoms such as joint pain, skin rash are common during the febrile stage. On the basis of only clinical presentation, it is difficult to pin-point the exact etiology for PFR. Serological investigations, polymerase chain reaction, and knowledge of concurrent epidemics in the community may help to identify the etiological organism. Bacterial causes of PFR such as rickettsia and typhoid are treated with systemic antibiotics, with or without systemic steroid therapy, whereas PFR of viral causes such as chikungunya, dengue, West Nile virus, and Zika virus have no specific treatment and are managed with steroids. Nevertheless, many authors have advocated mere observation and the uveitis resolved with its natural course of the disease. In this article, we have discussed the clinical features, pathogenesis, investigations, and management of PFR.

Miliary microaneurysms: An angiographic biomarker of leukemic retinopathy?

A 16-year-old girl was referred as retinitis and vasculitis post-typhoid fever. Fundus examination revealed bilateral pseudo-sheathing, scattered hemorrhages with retinal infiltrates. Wide-field fundus fluorescein angiography (FFA) showed peripheral vascular hyperfluorescence; 55° FFA images showed a "firecracker-like" peripheral vasculature, but a closer look revealed miliary microaneurysms (MAs). Peripheral smear examination clinched the diagnosis of chronic myeloid leukemia. MAs on FFA in leukemic retinopathy have been frequently described in the literature. Our report emphasizes its presence, miliary nature, and need for closer inspection of FFA images. We believe that this angiographic sign has potential to become one of the imaging biomarkers of leukemic retinopathy.

Emerging infectious uveitis: Chikungunya, dengue, Zika and Ebola: A review

Recently recognized forms of uveitis include intraocular inflammations that occur during or following one of several emerging infectious diseases: chikungunya fever, dengue, Zika virus disease and Ebola virus disease. Anterior, intermediate, posterior and pan-uveitis have been described in individuals infected with chikungunya virus. Persons who contract dengue or Zika viruses also may develop different types of uveitis in the course of the infection: maculopathy is a common manifestation of dengue eye disease, and Zika eye disease may cause hypertensive anterior uveitis or mimic a white dot syndrome. Up to one-third of Ebola survivors develop aggressive uveitis, which is frequently associated with vision loss and complicated by cataract. There are no specific anti-viral drugs for these forms of uveitis, and thus treatment is largely supportive. In this article, we summarize the systemic infectious diseases and virology, and describe the clinical presentations, outcomes and management of emerging viral forms of uveitis.

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.

Acute multifocal retinitis: a retrospective review of 35 cases

Background

Acute multifocal retinitis is a rare condition that has been considered to be often idiopathic. The purpose of this study was to analyze clinical features and causes of acute multifocal retinitis.

Results

This study is a retrospective review of the charts of 35 patients with acute multifocal retinitis. Patients with three or more retinal lesions in at least one eye, with at least one lesion of less than 500 μm in size were included. All patients had complete ophthalmological examination, fundus photography, and fluorescein angiography. Twelve patients (34.3%) had optical coherence tomography. An extensive work-up was performed including a detailed comprehensive medical history, examination by an internist and an infectious disease specialist, a chest X-ray, Mantoux test, and laboratory tests for syphilis, human immunodeficiency virus, Bartonella, and Rickettsia. Of the 35 patients, 25 (71.4%) had bilateral involvement and 10 (28.6%) had unilateral involvement (total number of eyes: 60). Mean best-corrected visual acuity (BCVA) was 20/25 (range, 20/1000–20/20). Retinal lesions ranged from 3 to more than 20 in number in at least 1 eye, and from 150 to 1500 μm in size. Associated findings included mild anterior chamber inflammation in 5 eyes (8.3%), mild vitritis in 46 eyes (76.7%), optic disc swelling in 9 eyes (15%), macular star in 4 eyes (6.7%), exudative retinal detachment in 6 eyes (10%), and branch retinal artery occlusion in 6 eyes (10%). Acute multifocal retinitis was found to be caused by Rickettsia conorii infection in 20 patients (57.1%), Rickettsia typhi infection in 4 patients (11.4%), cat-scratch disease in 8 patients (22.9%), and syphilis in 1 patient (2.9%). It was idiopathic in two patients (5.7%). Retinal lesions resolved without scarring in 3 to 12 weeks in all but three eyes (5%), in which residual retinal pigment epithelial changes were noted.

Conclusion

Rickettsial disease was the most common cause of acute multifocal retinitis. Other identified causes included cat-scratch disease and syphilis, and a very small subset of patients was diagnosed with idiopathic multifocal retinitis.