Unilateral Toxoplasma retinochoroiditis with frosted branch angiitis: a multimodal imaging study.

A woman in her late 30s presented with sudden diminution of vision, redness and pain in the right eye (OD) of 10 days' duration. Best corrected visual acuity (BCVA) was 20/160 in OD and 20/20 in the left eye (OS). Anterior segment of OD showed keratic precipitates, flare 3+, cells 2+ and a festooned pupil. Vitreous haze and cells were seen in OD. Frosted branch angiitis (FBA) was seen in all quadrants in OD and old Toxoplasma scar was seen in both eyes. Serum toxoplasma immunoglobulin G (IgG) was positive and IgM negative, and PCR of an aqueous humour sample was negative for Toxoplasma She was diagnosed with toxoplasa retinochoroiditis in OD and treated with intravitreal clindamycin injections, oral anti-Toxoplasma antibiotics and steroids. Three months later, her BCVA in OD was 20/40 with resolving inflammation. She presented 2 months later with a new focus of retinochoroiditis without FBA and an old Toxoplasma scar.

Long-term Ocular Outcomes in Congenital Toxoplasmosis Treated Perinatally.

BACKGROUND: Congenital toxoplasmosis (CT) can be accompanied by serious organ manifestations, particularly retinochoroiditis, and may occur throughout life. We aimed to monitor long-term ocular prognosis in a large French cohort of patients with CT and its changes over time in the context of mandatory prenatal screening (since 1992) and incidence decrease since 2008. METHODS: Patients with CT diagnosed between 1987 and 2021 were prospectively included and followed for up to 35 years. The effect of the period of conception on the risk of first retinochoroiditis has been tested using a flexible extension of the Cox model. Incidence rates of retinochoroiditis were estimated. RESULTS: A total of 646 infected live born children were followed for a median of 12 years (range, 0.5-35); 187 patients (29%) had at least 1 ocular lesion (first at a median age of 5 years; range, 0-26 years) with peaks at 7 and 12 years. Early maternal infection and the presence of nonocular signs at birth were associated with a higher risk of retinochoroiditis, whereas delayed diagnosis of CT (after birth versus before or at birth) was associated with a lower risk (13% decrease for each additional month after birth; P = .01). A period effect for the risk of developing retinochoroiditis in patients born after 2008 was not detected. CONCLUSIONS: Despite prenatal screening and prolonged perinatal treatment, retinochoroiditis is not a rare event in French patients with CT and can occur well into adulthood, with peak incidences at 7 and 12 years of age. It rarely causes severe damage but warrants regular follow-up into adulthood.

An alternative method to establish an early acute ocular toxoplasmosis model for experimental tests.

PURPOSE: To provide a simple alternative acute ocular toxoplasmosis model with great reproducibility for experimental tests that demand monitoring of the ocular lesion. METHODS: ME49-wt and ME49-GFP tachyzoites from cell culture were used to infect male C57BL6 mice by intraperitoneal injection. B1 expression by real-time polymerase chain reaction (qPCR) assay was used to detect the presence of T. gondii in ocular tissue at the beginning of the infection. Fluorescence microscopy and histopathology analysis were carried out to assess the evolution of the acute infection up to 20 days in both eyes of infected mice. RESULTS: All mice infected with the 104 tachyzoites showed B1 expression in the retina of both eyes, in the RPE (retinal pigment epithelium), and choroid structures, after 5 days of infection. Tachyzoites of the ME49-GFP strain were easily detected by fluorescence microscopy in the retina tissue of mice after 5 days post-infection. After 20 days, mice inflammatory cell infiltrates and a disorganized morphology of the retinal laminar architecture were observed. CONCLUSION: Infection of C57BL6 mice via intraperitoneal with 104 tachyzoites of the ME49-GFP strain from cell culture is a suitable model for acute ocular toxoplasmosis. This model has great reproducibility in establishing the ocular lesion since day 5 post-infection. This model can be suitable for experimental tests of chemotherapy and the investigation of the role of the immune response on the development of uveitis.

Metagenomic analysis of the ocular toxoplasmosis in children uveitis from Fayoum governorate, Egypt.

Granulomatous anterior uveitis with single or numerous gelatinous nodules was found in children living in rural Egypt. All ocular diseases were originally thought to be water-born and related to digenic flukes. The current study sought to learn more about the causes of anterior granulomatous uveitis in Egyptian youngsters who used to swim in rural water canals. 50 children with eye lesions that had not responded to medical treatment were recruited. Four samples were surgically extracted and examined using real-time PCR, transmission electron microscopy (TEM), and shotgun metagenomic sequencing (SMS). Toxoplasma gondii was detected free within the syncytium's distal section, while the proximal part exhibited active synthesis of a presumably extra-polymeric material, possibly released by the microbial population. Toxoplasma gondii was found in 30 samples. Serologically, distinct anti-Toxoplasma antibodies were not found in 91.6% of patients. SMS showed that the T. gondii ME 49 strain had the greatest percentage (29-25%) in all samples within an Acinetobacter-containing microbial community. These findings suggested that these bacteria entered the body via the exterior route rather than the circulatory route. The lack of genetic evidence for subsequent parasite stages invalidates the prior findings about the assumed trematode stage.

Considerations in the management of ocular toxoplasmosis in pregnancy: a review of literature.

Ocular toxoplasmosis is the most common cause of infectious posterior uveitis. Available literature is still conflicting regarding the incidence of recurrence during pregnancy as various calculations were employed in the different published studies. Although earlier reports have suggested a difference in presentation and an increase in severity during pregnancy, newer studies appear to show otherwise. Further diagnostic testing, including serologic and intraocular fluid sampling, may be indicated to increase the diagnostic accuracy in this special population of patients. The management of ocular toxoplasmosis during pregnancy is challenging as the foetus is additionally considered in the choice of treatment. Traditionally preferred anti-toxoplasmosis regimens containing antifolate drugs, such as pyrimethamine and trimethoprim-sulfamethoxazole, cannot be used routinely in pregnant patients, especially during the first trimester. This review includes literature on alternative treatments for ocular toxoplasmosis during pregnancy, including spiramycin and intravitreal treatment options.

Serous macular detachment in ocular toxoplasmosis: A review.

Ocular toxoplasmosis, a disease of the eye caused by the protozoan parasite Toxoplasma gondii, represents a common cause of posterior uveitis. The Authors review the current Literature regarding the uncommon presentation of ocular toxoplasmosis as macular serous retinal detachment (SRD). It is imperative to keep in mind that inflammatory SRD is a possible presentation of toxoplasmic retinochoroiditis. Underestimation of this clinical scenario and treatment with steroids alone without appropriate antiparasitic drugs, could lead to devastating consequences.

Fundus topographical distribution patterns of ocular toxoplasmosis.

BACKGROUND: To establish topographic maps and determine fundus distribution patterns of ocular toxoplasmosis (OT) lesions. METHODS: In this retrospective study, patients who presented with OT to ophthalmology clinics from four countries (Argentina, Turkey, UK, USA) were included. Size, shape and location of primary (1°)/recurrent (2°) and active/inactive lesions were converted into a two-dimensional retinal chart by a retinal drawing software. A final contour map of the merged image charts was then created using a custom Matlab programme. Descriptive analyses were performed. RESULTS: 984 lesions in 514 eyes of 464 subjects (53% women) were included. Mean area of all 1° and 2° lesions was 5.96±12.26 and 5.21±12.77 mm2, respectively. For the subset group lesions (eyes with both 1° and 2° lesions), 1° lesions were significantly larger than 2° lesions (5.52±6.04 mm2 vs 4.09±8.90 mm2, p=0.038). Mean distances from foveola to 1° and 2° lesion centres were 6336±4267 and 5763±3491 µm, respectively. The majority of lesions were found in temporal quadrant (p<0.001). Maximum overlap of all lesions was at 278 µm inferotemporal to foveola. CONCLUSION: The 1° lesions were larger than 2° lesions. The 2° lesions were not significantly closer to fovea than 1° lesions. Temporal quadrant and macular region were found to be densely affected underlining the vision threatening nature of the disease.

Ocular toxoplasmosis following anti-tumour necrosis factor-α therapy combined with oral methotrexate therapy: A case report and review of literature.

Purpose: To report a case of ocular toxoplasmosis following long-term treatment with adalimumab and review the literature on ocular toxoplasmosis following anti-Tumour necrosis factor-α therapy. Method: A retrospective chart review of A 21-year-old male who developed retinochoroiditis in his left eye following adalimumab therapy combined with oral methotrexate. Result: A known patient of juvenile idiopathic arthritis (JIA) on adalimumab and oral methotrexate for the last four years presented to us with a blurring of vision for the last 15 days. Fundus examination of the left eye revealed severe vitritis and two patches of retinochoroiditis in the inferior part of the fundus. Subsequent investigations confirmed it to be a case of toxoplasma retinochoroiditis, and he responded to anti-toxoplasma treatment. A review of literature on a similar topic revealed five such cases, and the index case was the first such report in patients with JIA. Conclusion: The index case highlights the importance of early recognition and management of opportunistic infections in patients receiving biologicals.

Retinal ferroptosis as a critical mechanism for the induction of retinochoroiditis during ocular toxoplasmosis.

Toxoplasmosis is a major infectious disease, affecting approximately one-third of the world's population; its main clinical manifestation, ocular toxoplasmosis (OT), is a severe sight-threatening disease. Nevertheless, the diagnosis of OT is based on clinical findings, which needs improvement, even with biochemical tests, such as polymerase chain reaction and antibody detections. Furthermore, the efficacy of OT-targeted treatment is limited; thus, additional measures for diagnosis and treatments are needed. Here, we for the first time report a significantly reduced iron concentration in the vitreous humor (VH) of human patients infected with OT. To obtain further insights into molecular mechanisms, we established a mouse model of T. gondii infection, in which intravitreally injected tracer 57Fe, was accumulated in the neurosensory retina. T. gondii-infected eyes showed increased lipid peroxidation, reduction of glutathione peroxidase-4 expression and mitochondrial deformity in the photoreceptor as cristae loss. These findings strongly suggest the involvement of ferroptotic process in the photoreceptor of OT. In addition, deferiprone, an FDA-approved iron chelator, reduced the iron uptake but also ameliorated toxoplasma-induced retinochoroiditis by reducing retinal inflammation. In conclusion, the iron levels in the VH could serve as diagnostic markers and iron chelators as potential treatments for OT.

Elevated interleukin-10 levels in patients with ocular toxoplasmosis.

In elderly patients, ocular toxoplasmosis is one of the most common etiologies of uveitis, which should be differentially diagnosed from ocular lymphoma, another common pathology of uveitis in older adults. The high level of interleukin (IL)-10 and an IL-10/IL-6 ratio higher than 1 (>1.0) are helpful parameters to diagnose ocular lymphoma. In this study, we used aqueous humor samples to detect 4 cases of ocular toxoplasmosis in patients with high levels of IL-10 and an IL-10/IL-6 ratio higher than 1. Our results show that ocular toxoplasmosis may be associated with increased cytokine levels in aqueous humor.

Acquired Ocular Toxoplasmosis: a Case Report and Review of the Literature.

BACKGROUND: Toxoplasmosis is a zoonotic illness caused by Toxoplasma gondii. Ocular infection frequently manifests as acute necrotizing retinal chorioretinitis. In this paper, we describe a case of retinal chorioretinitis caused by Toxoplasma gondii infection, as well as the most recent diagnostic and treatment techniques. METHODS: Serum and vitreous fluid were collected and analyzed, and PCR for Toxoplasma gondii DNA, ELISA for Toxoplasma gondii IgG and Goldmann-Witmer coefficient, fundus fluorescein angiography (FFA), indocyanine green angiography (ICGA), and fundus autofluorescence were done (FAF). RESULTS: Toxoplasma gondii DNA (-), serum and vitreous IgG from Toxoplasma gondii (+) cells, and the Goldmann-Witmer coefficient of Toxoplasma gondii were all considerably enhanced, indicating Toxoplasma gondii infection. Antiparasitic infection in combination with an anti-inflammatory glucocorticoid were given, laser treatment of the fundus was provided, and the patient's condition has been stable with no indication of recurrence to date following conclusion of therapy. CONCLUSIONS: Toxoplasma gondii can infect the whole retina, causing variable degrees of visual impairment; thus, rapid diagnosis and tailored therapy are necessary to enhance prognosis and reduce disease recurrence.

Toxoplasmic maculopathy with bacillary layer detachment in a pediatric patient.

We report the case of a 14-year-old girl with ocular toxoplasmosis presenting with severe panuveitis with anterior segment involvement, moderate vitreous haze, focal retinochoroiditis, extensive retinal periphlebitis, and macular bacillary layer detachment. Toxoplasmosis treatment was complicated by Stevens-Johnson syndrome, which developed 8 days after starting trimethoprim-sulfamethoxazole.

Ocular Toxoplasmosis.

INTRODUCTION: Ocular toxoplasmosis is the leading cause of posterior uveitis worldwide, affecting individuals acrossdifferent age groups. The key to reducing vision loss includes prompt diagnosis and treatment. However, despite the prevalence of ocular toxoplasmosis, there has been little consensus regarding its pathophysiology,clinical features, diagnosis, and especially management. METHODS: The data sources were literature reviews, including Pub Med and Medline databases. Search terms included toxoplasmosis, retinitis, vasculitis, vitritis, uveitis alone or in combination with, serum, aqueous, vitreous eye, ocular and review. RESULTS: In this review paper, we have sought to provide an overview of the pathophysiology, epidemiology, and clinical features of the disease, both based on current literature and our own clinical experience. We have also discussed the use of serology, ocular fluid, and ophthalmic investigations that could further facilitate the diagnosis of ocular toxoplasmosis.Different management strategies have been reported worldwide, including newer approaches such as local therapy. CONCLUSION: A better understanding of critical aspects of ocular toxoplasmosis will hopefully lead to reduced morbidity, including blindness associated with this condition.

Current practice in the management of ocular toxoplasmosis.

BACKGROUND: Ocular toxoplasmosis is common across all regions of the world. Understanding of the epidemiology and approach to diagnosis and treatment have evolved recently. In November 2020, an international group of uveitis-specialised ophthalmologists formed the International Ocular Toxoplasmosis Study Group to define current practice. METHODS: 192 Study Group members from 48 countries completed a 36-item survey on clinical features, use of investigations, indications for treatment, systemic and intravitreal treatment with antiparasitic drugs and corticosteroids, and approach to follow-up and preventive therapy. RESULTS: For 77.1% of members, unilateral retinochoroiditis adjacent to a pigmented scar accounted for over 60% of presentations, but diverse atypical presentations were also reported. Common complications included persistent vitreous opacities, epiretinal membrane, cataract, and ocular hypertension or glaucoma. Most members used clinical examination with (56.8%) or without (35.9%) serology to diagnose typical disease but relied on intraocular fluid testing-usually PCR-in atypical cases (68.8%). 66.1% of members treated all non-pregnant patients, while 33.9% treated selected patients. Oral trimethoprim-sulfamethoxazole was first-line therapy for 66.7% of members, and 60.9% had experience using intravitreal clindamycin. Corticosteroid drugs were administered systemically by 97.4%; 24.7% also injected corticosteroid intravitreally, almost always in combination with an antimicrobial drug (72.3%). The majority of members followed up all (60.4%) or selected (35.9%) patients after resolution of acute disease, and prophylaxis against recurrence with trimethoprim-sulfamethoxazole was prescribed to selected patients by 69.8%. CONCLUSION: Our report presents a current management approach for ocular toxoplasmosis, as practised by a large international group of uveitis-specialised ophthalmologists.