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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

A new look into uveitis in Colombia: changes in distribution patterns and clinical characteristics over the last 25 years

PURPOSE

To describe the distribution patterns and clinical characteristics of patients diagnosed with uveitis at a specialized uveitis center in Bogotá, Colombia, from 2013 to 2021 and compare these patterns with the previously reported between 1996 and 2006.

METHODS

We performed an observational descriptive cross-sectional study systematically reviewing clinical records of patients attending between 2013 and 2021. Data were analyzed and compared with previous reports.

RESULTS

Of the 489 patients with uveitis, 310 were females (63.4%). The mean age of onset was 38.7, with a range between 1 and 83 years. Bilateral (52.8%), anterior (45.8%), non-granulomatous (90.8%), and recurrent (47.6%) were the most common types of uveitis found in our population sample. The most common cause of uveitis in this study was idiopathic, followed by toxoplasmosis and HLA-B27 + associated uveitis, which differs from the previous Colombian study where ocular toxoplasmosis was the most frequent cause. This highlights a significant shift from infectious etiologies to more immune-mediated processes as the cause of uveitis in Colombia nowadays.

CONCLUSION

The results of this study provide a comparison between the clinical patterns of presentation of uveitis from 1996 to 2006 and the patterns observed from 2013 to 2021, enhancing awareness about the changing dynamics of uveitis in Colombia to guide a better understanding of the diagnosis, classification, and correlation with other systemic conditions of the disease.

Antibodies against Toxoplasma gondii positive in serum and aqueous humor to diagnose clinically suspected ocular toxoplasmosis: A case report

INTRODUCTION

Previously, diagnosis of ocular toxoplasmosis is based on clinical symptoms and Toxoplasma serology. Checking serological indicators often cannot reflect the real intraocular situation, and may even mislead clinicians to make wrong judgments.

PATIENT CONCERNS

A 38-year-old male patient visited our ophthalmology clinic with a chief complaint of decreased vision for about 5 days in his right eye.

DIAGNOSIS

Aqueous humor sample analysis found Toxoplasma DNA detectable, and Toxoplasma immunoglobulin G (IgG) and immunoglobulin M (IgM) to be positive. His serum Toxoplasma IgG was also positive (10.04 IU/mL; reference range: 0 to 7.2 IU/mL). Therefore, the final diagnose was ocular toxoplasmosis involving his right eye.

INTERVENTIONS

Oral prednisone 60 mg/day and azithromycin 0.25 g/day were started. Oral antibiotic treatment for toxoplasma was continued for 4 weeks, and prednisone followed by weekly stepwise tapering in steps of 10 mg/day.

OUTCOMES

The BCVA and fundus of right eye remained stable after treatment at follow-up.

CONCLUSIONS

This article reported a case of ocular Toxoplasma gondii infection diagnosis by serum and aqueous humor antibody tests. We provide some additional information on the T gondii infection diagnosis.

In vitro and in vivo anti−Toxoplasma activities of HDAC inhibitor Panobinostat on experimental acute ocular toxoplasmosis

Ocular toxoplasmosis (OT) is retinochoroiditis caused by Toxoplasma gondii infection, which poses a huge threat to vision. However, most traditional oral drugs for this disease have multiple side effects and have difficulty crossing the blood-retinal barrier, so the new alternative strategy is required to be developed urgently. Histone deacetylases (HDAC) inhibitors, initially applied to cancer, have attracted considerable attention as potential anti-Toxoplasma gondii drugs. Here, the efficacy of a novel HDAC inhibitor, Panobinostat (LBH589), against T. gondii has been investigated. In vitro, LBH589 inhibited the proliferation and activity of T. gondii in a dose-dependent manner with low toxicity to retinal pigment epithelial (RPE) cells. In vivo, optical coherence tomography (OCT) examination and histopathological studies showed that the inflammatory cell infiltration and the damage to retinal architecture were drastically reduced in C57BL/6 mice upon treatment with intravitreal injection of LBH589. Furthermore, we have found the mRNA expression levels of inflammatory cytokines were significantly decreased in LBH589–treated group. Collectively, our study demonstrates that LBH589 holds great promise as a preclinical candidate for control and cure of ocular toxoplasmosis.

TOXOPLASMOSIS RETINOCHOROIDITIS MASQUERADING AS ENDOGENOUS ENDOPHTHALMITIS IN A CASE OF CONGENITAL LONG QT SYNDROME

PURPOSE

To describe the diagnostic and treatment challenges of a case of presumed acquired macula-involving toxoplasmosis retinochoroiditis.

METHODS

Case report of a woman with congenital long QT syndrome presenting with retinochoroiditis after undergoing a cardiac procedure. Laboratory analysis, ocular fluid biopsy, and multimodal imaging were obtained.

RESULTS

Ophthalmic examination was significant for decreased vision and a macula-involving chorioretinal lesion concerning for endogenous endophthalmitis. Multimodal imaging showed a focal, full-thickness necrotizing process associated with vitritis, retinal edema, and choroidal thickening. Analysis of peripheral blood revealed elevated serum toxoplasma Immunoglobulin G titers. Blood cultures and a transesophageal echocardiogram were negative for endocarditis. Aqueous and vitreous specimens were negative for an infectious polymerase chain reaction panel, including toxoplasmosis and negative bacterial and fungal cultures. A diagnosis of presumed acquired toxoplasmosis retinochoroiditis was made and treated with a combination of oral and intravitreal antiparasitic medications resulting in healing of the retinochoroiditis.

CONCLUSION

To the authors' knowledge, this is the first reported case of acquired toxoplasmosis retinochoroiditis in an immunocompetent patient with congenital long QT syndrome masquerading as endogenous endophthalmitis. The association of congenital long QT syndrome and a recent cardiac procedure with a risk for endogenous endophthalmitis complicated the diagnosis, clinical course, and treatment options. Our case emphasizes the importance of a thorough patient history, comprehensive clinical examination, and supportive multimodal imaging that were used to characterize the infectious process and guide empirical treatment. In addition, laboratory analysis, comanagement with other specialists, and evaluating the response to antitoxoplasma therapy were all instrumental in the eventual diagnosis and treatment of ocular toxoplasmosis in this atypical case.

Treatment of a full-thickness macular hole and retinal detachment secondary to toxoplasma chorioretinitis that developed shortly after COVID-19: A case report

Although ocular toxoplasmosis is usually a self-limiting infection, it can lead to severe reduction in visual acuity due to intense vitreous inflammation or involvement of posterior segment structures. Depending on the severity of intraocular inflammation, serious complications, including epiretinal membrane or retinal detachment may develop. In this paper, we aim to present a case that complicated by both a full-thickness macular hole and retinal detachment secondary to toxoplasmosis chorioretinitis that developed shortly after the novel coronavirus disease (COVID-19) and discuss our treatment approach. After the patient was diagnosed based on a routine ophthalmological examination, fundus imaging, and serological examination, functional and anatomical recovery was achieved through systemic antibiotherapy and vitreoretinal surgery. Full-thickness macular hole and retinal detachment are rare complications of ocular toxoplasmosis. However, there are only few publications in the literature concerning these complications and their surgical treatment. In this case report, we demonstrated the success of vitreoretinal surgery combined with antibiotic therapy on the posterior segment complications of ocular toxoplasmosis.

Ocular toxoplasmosis: a review of the current diagnostic and therapeutic approaches

PURPOSE

This review aims to summarize the current knowledge concerning the clinical features, diagnostic work-up and therapeutic approach of ocular toxoplasmosis focusing mainly on the postnatally acquired form of the disease.

METHODS

A meticulous literature search was performed in the PubMed database. A supplementary search was made in Google Scholar to complete the collected items.

RESULTS

Ocular toxoplasmosis is one of the most frequent infectious etiologies of posterior uveitis. It typically presents with retinochoroiditis. Setting an accurate diagnosis depends to a considerable degree on detecting characteristic clinical characteristics. In addition to the evaluation of clinical features, the diagnosis of toxoplasmosis relies at a large degree on serologic testing. The detection of the parasite DNA in the aqueous or vitreous humor can provide evidence for a definitive diagnosis. The current mainstay for the treatment, if necessary, is the use of oral antibiotic with systemic corticosteroids. Recent evidence suggests other therapeutic approaches, such as intravitreal antibiotics can be used.

CONCLUSION

Recent developments in the diagnostic and therapeutic approach have contributed to preventing or limiting vision loss of patients suffering from ocular toxoplasmosis. Further studies are required to provide a better understanding of epidemiology, pathogenesis, diagnosis, and treatment with a significant impact on the management of this challenging clinical entity.

ATYPICAL FORMS OF EYE TOXOPLASMOSIS IN CHILDHOOD. CASE REPORTS

AIM

To present an outline of acquired atypical forms of ocular toxoplasmosis (OT) in childhood, with reference to the 100th anniversary of the discovery of this etiology by Professor Jank&#367; from Czechoslovakia, who was first to describe the clinical congenital picture of OT characterised by macular scar.

MATERIAL AND METHODS

Symptoms of intraocular bilateral neuritis appeared in a 6-year-old girl, with visual acuity (VA) bilaterally 0.1. Toxoplasmic etiology was demonstrated in laboratory tests, and the patient was immunocompetent. Following treatment with macrolide antibiotic and parabulbar application of corticosteroid, the condition was normalised stably at VA 1.0 in both eyes. Bilateral retinal vasculitis was determined in an 8-year-old boy, with VA of 0.25 in the right eye and 0.25 in the left, with a medical history of strabismus detected after suffering from varicella. The examination for toxoplasmosis was negative, but pronounced general hypogammaglobulinaemia classes IgG, IgM and IgA was detected. Immunosuppressive and immunomodulatory therapy did not produce the desired effect, and the condition progressed to retinochoroiditis. Due to blindness and dolorous glaucoma, enucleation of the right eye was performed at the age of 15 years. Histologically toxoplasmic cysts with bradyzoites were detected, a subsequent laboratory test demonstrated toxoplasmic etiology upon a background of persistent regressing hypogammaglobulinaemia. General anti-toxoplasma and subsequent immunosuppressive treatment did not produce the desired effect, and at the age of 22 years the patient lost his sight also in the left eye.

CONCLUSION

Atypical form of OT intraocular neuritis in an immunocompetent patient had a favourable course, whereas retinal vasculitis with retinochoroiditis in a temporarily immunocompromised patient ended in bilateral blindness.

ACUTE MYOCARDITIS WITH CARDIOGENIC SHOCK AND MULTIPLE ORGAN FAILURE, FOLLOWED BY BILATERAL PANUVEITIS MASQUERADING AS ENDOGENOUS ENDOPHTHALMITIS, DUE TO TOXOPLASMA GONDII IN AN IMMUNOCOMPETENT PATIENT

PURPOSE

To report a case of systemic and ocular toxoplasmosis in an immunocompetent patient, who developed myocarditis with resulting cardiogenic shock and multiple organ failure, followed by bilateral panuveitis masquerading as endogenous endophthalmitis.

METHODS

Single case report with images.

RESULTS

A 59-year-old man with a history of monoclonal gammopathy of undetermined significance and associated scleromyxedema but otherwise immunocompetent was admitted to the intensive care unit for cardiogenic shock and multiple organ failure due to presumed viral myocarditis. After hospital discharge, ophthalmic examination revealed what seemed to be endogenous fungal endophthalmitis in both eyes. The ocular inflammation failed to improve on local and systemic antifungal therapies. After repeated testing and vitrectomy, the causative organism responsible for his intraocular inflammation remained elusive. The patient was then found to have significantly elevated serum titers of anti-Toxoplasma gondii IgG and IgM, followed by an appearance of a focal retinochoroidal lesion more typical of ocular toxoplasmosis. Systemic anti-Toxoplasma therapy led to resolution of intraocular inflammation, and the patient had since fully recovered from the myocarditis and its multiple comorbidities. Of note, myocardial biopsy and polymerase chain reaction testing of aqueous and vitreous fluids were all negative for Toxoplasma.

CONCLUSION

Even in an immunocompetent patient, Toxoplasma can result in myocarditis with significant morbidities and even death, and its ocular manifestation may be quite different from the classic focal retinochoroiditis. In addition, polymerase chain reaction analysis of ocular fluids can be unreliable in an immunocompetent host, and thus treatment decision should be guided by clinical history and examination findings.

Classification Criteria for Toxoplasmic Retinitis

PURPOSE

To determine classification criteria for toxoplasmic retinitis.

DESIGN

Machine learning of cases with toxoplasmic retinitis and 4 other infectious posterior uveitides / panuveitides.

METHODS

Cases of infectious posterior uveitides / panuveitides were collected in an informatics-designed preliminary database, and a final database was constructed of cases achieving supermajority agreement on diagnosis, using formal consensus techniques. Cases were split into a training set and a validation set. Machine learning using multinomial logistic regression was used on the training set to determine a parsimonious set of criteria that minimized the misclassification rate among the infectious posterior uveitides / panuveitides. The resulting criteria were evaluated on the validation set.

RESULTS

Eight hundred three cases of infectious posterior uveitides / panuveitides, including 174 cases of toxoplasmic retinitis, were evaluated by machine learning. Key criteria for toxoplasmic retinitis included focal or paucifocal necrotizing retinitis and either positive polymerase chain reaction assay for Toxoplasma gondii from an intraocular specimen or the characteristic clinical picture of a round or oval retinitis lesion proximal to a hyperpigmented and/or atrophic chorioretinal scar. Overall accuracy for infectious posterior uveitides / panuveitides was 92.1% in the training set and 93.3% (95% confidence interval 88.2, 96.3) in the validation set. The misclassification rates for toxoplasmic retinitis were 8.2% in the training set and 10% in the validation set.

CONCLUSIONS

The criteria for toxoplasmic retinitis had a low misclassification rate and seemed to perform sufficiently well for use in clinical and translational research.

CONGENITAL TOXOPLASMOSIS ASSOCIATED WITH TRACTIONAL RETINAL DETACHMENT

PURPOSE

We report a case of congenital toxoplasmosis associated with retinal detachment.

METHODS

A 9-month-old white boy presented a unilateral tractional retina detachment associated with congenital toxoplasmosis retinochoroiditis.

RESULTS

The diagnosis is supported by positive IgG (>400) for toxoplasmosis and intracranial calcification on magnetic resonance imaging, along with positive family history of Toxoplasma infection in the mother.

CONCLUSION

Tractional retinal detachment is an infrequent and unconventional presentation of congenital Toxoplasma infection. Inflammatory interference with normal sequence of vitreous development may explain pathogenesis of tractional retinal detachments in the setting of congenital ocular toxoplasmosis.

Ocular Toxoplasmosis among Livestock Farmers and Raw Meat Handlers in Uyo, Nigeria

BACKGROUND

Toxoplasmosis is the commonest cause of infectious posterior uveitis in humans and can lead to blindness and low vision in both immune-competent and immunecompromised persons worldwide. The aim of this study was to determine the prevalence of Ocular Toxoplasmosis (OT) and potential risk factors among livestock farmers and raw meat handlers in Uyo.

METHODS

This was a descriptive cross-sectional community-based study involving clinical eye examination, laboratory detection of anti-Toxoplasma gondii IgG antibody and HIV testing. Participants' other information was obtained using interviewer-administered questionnaire.

RESULTS

There were 339 participants aged 15-78 (mean 34.8±11.6) years,283 (83.5%) were males 56(16.5%) were females; 189 (55.8%) tested seropositive for anti-Toxo. gondiiIgG antibodies. Eight (2.4%) had presumed ocular toxoplasmosis (POT); 6 of the 8 were seropositive for anti-T.gondiiIgG antibody; and 2 of the 8 POT (25%) were HIV-seropositive. Of the 189 who were anti-T.gondiiIgG antibody seropositive, 6 (3.2%) had OT. Factors associated with OT were age (31-50 years) and female gender (P = 0.049 and 0.001, respectively). HIV infection was associated with POT (P=0.033). Most of the ocular lesions (87.5%) were unilateral and located at the posterior pole (77.7%).

CONCLUSION

The prevalence of presumed ocular toxoplasmosis (POT) and ocular toxoplasmosis (OT) among livestock farmers and raw meat handlers in Uyo are 2.4% and 1.8%, respectively. Potential risk factors are being female, and persons between fourth and fifth decades of life. Awareness creation on toxoplasmosis among this occupational group is advocated.

Ocular toxoplasmosis: phenotype differences between toxoplasma IgM positive and IgM negative patients in a large cohort

PURPOSE

To investigate the differences in demographics and clinical characteristics of patients diagnosed with ocular toxoplasmosis according to their IgM status.

METHODS

Retrospective case note analysis was carried out on patients who tested positive for serum Toxoplasma gondii-specific IgM antibodies (IgM+) as well as a comparator group who tested negative for serum IgM (IgM-), but positive for serum IgG. Patient demographics and clinical features were compared between the two groups to evaluate for any significant differences.

RESULTS

One hundred and six patients were included in the study between March 2011 and June 2018, consisting of 37 in the IgM +group and 69 in the IgM- group. Patients in the IgM +group were significantly older (51.1 vs 34.1 years, p<0.0001), more likely to present with central macular lesions (32% vs 12%, p=0.012), and more likely to develop rhegmatogenous retinal detachment (11% vs 1%, p=0.049). In contrast, patients in the IgM- group were more likely present with pain (20% vs 3%, 0.017) and exhibit more severe inflammation of the anterior chamber and vitreous (p<0.05). Overall, retinal lesions were more likely to be superotemporal (55%) and superonasal (31%). Furthermore, age was associated with larger (p=0.003) and more peripheral lesions (p=0.007).

CONCLUSIONS

This study demonstrated significant differences in clinical characteristics of ocular toxoplasmosis according to serum IgM status. IgM+ patients were older, less likely to report pain, had lower levels of intraocular inflammation, but were more likely to have macular involvement. We also found age to be correlated with larger and more peripheral lesions.

Bilateral focal choroidal excavations in a patient with Stargardt disease and ocular toxoplasmosis

INTRODUCTION

Focal choroidal excavation (FCE) is a concavity of the choroid detected on optical coherence tomography (OCT). It is usually idiopathic and the affected eyes are otherwise healthy with near-normal overlying retinal architecture and good visual acuity.

PURPOSE

To report a case of bilateral conforming FCE in the setting of Stargardt disease and inactive ocular toxoplasmosis.

CASE REPORT

A 20-year-old man with known history of Stargardt disease, healed toxoplasmosis, and high myopia presented to our ophthalmology department for follow-up examination and was found with bilateral FCEs not present in any of his previous examinations.

CONCLUSION

FCEs have been reported in the literature in otherwise healthy eyes as well as a broad spectrum of ocular diseases. The case herein reported Stargardt disease, toxoplasmosis, and high myopia all could potentially contribute to the pathogenesis of these findings. Further studies are needed to define etiologies as well as clinical significance and course of FCEs.

Long-term Results of Trimethoprim-Sulfamethoxazole Versus Placebo to Reduce the Risk of Recurrent Toxoplasma gondii Retinochoroiditis

PURPOSE

To compare the effects of 1 year of treatment with trimethoprim-sulfamethoxazole (TMP-SMZ) vs placebo in reducing the risk of recurrence of toxoplasmic retinochoroiditis during a 6-year follow-up period.

DESIGN

Randomized, double-masked clinical trial.

METHODS

This cohort included 141 subjects recruited in Campinas, Brazil. The inclusion criterion was unilateral active recurrent toxoplasmic retinochoroiditis. All subjects were treated with 1 dose of TMP-SMZ (160 mg/800 mg) twice daily for 45 days, and all lesions healed after this treatment. After this initial treatment, subjects were randomly assigned to group 1 (1 TMP-SMZ dose every other day for 311 days) or group 2 (1 identical placebo tablet containing starch with no active ingredients every other day for 311 days). Between the second and sixth years of follow-up appointments, none of the subjects received treatment unless a new recurrence episode had occurred. The primary outcomes were recurrent toxoplasmic retinochoroiditis within the first year of follow-up and recurrent toxoplasmic retinochoroiditis in the 6 years of follow-up.

RESULTS

The cumulative probability of recurrence 1, 2, 3, 4, 5, and 6 years after the initial infection was, respectively, 13.0% (9/69), 17.4% (12/69), 20.3% (14/69), 23.2% (16/69), 26.1% (18/69), and 27.5% (19/69) in the placebo group and 0%, 0%, 0%, 0%, 0%, and 1.4% (1/72) in the TMP-SMZ group (P < .001; log-rank test). There were 3 cases (3/69; 4.3%) of multiple recurrences in the same individual in the placebo group. No treatment-limiting toxicity or side effects were observed in either group. New recurrences were more frequent among female subjects.

CONCLUSIONS

TMP-SMZ may be used safely for prophylaxis of recurrent toxoplasmic retinochoroiditis and may provide long-term benefits.

Multimodal Imaging of Punctate Outer Retinal Toxoplasmosis

BACKGROUND AND OBJECTIVE

To describe the multimodal imaging characteristics associated with punctate outer retinal toxoplasmosis (PORT).

PATIENTS AND METHODS

Multicenter, retrospective, observational case series of three patients who presented with PORT. Multimodal imaging was reviewed including optical coherence tomography (OCT), fundus autofluorescence, optical coherence tomography angiography, and conventional dye-based angiography.

RESULTS

Patient ages ranged from 13 years to 55 years. Each patient had multiple white, punctate outer retinal lesions in the affected eye at initial diagnosis. OCT showed both inner and outer retinal changes, including disruption of the ellipsoid and interdigitation zones and retinal pigment epithelium/Bruch's membrane complex, as well as punctate, preretinal, hyperreflective lesions at the vitreoretinal interface, which regressed with treatment.

CONCLUSION

Multimodal imaging is useful in diagnosing and monitoring treatment response in PORT, an uncommon presentation of ocular toxoplasmosis that must be differentiated from white dot syndromes or other causes of unilateral retinitis. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:281-287.].

Ocular Toxoplasmosis in a Tertiary Referral Center in Sydney Australia-Clinical Features, Treatment, and Prognosis

PURPOSE

The aim of this study was to provide a retrospective analysis of the presentation, demographics, and treatment regimens for ocular toxoplasmosis at a large tertiary referral uveitis center.

DESIGN

Retrospective cohort study.

PARTICIPANTS

A total of 48 patients with ocular toxoplasmosis who presented to Sydney Eye Hospital participated in this study.

METHODS

This is a retrospective review of patient files who presented to Sydney Eye Hospital between 2007 and 2016 with clinical features consistent with ocular toxoplasmosis. Baseline risk factors and treatment details were recorded and analyzed. Main outcome measures were visual acuity and relapse rate compared with other studies in ocular toxoplasmosis.

RESULTS

The median age was 35.5 (interquartile range 21-50) with 30 (60%) patients having no previous symptomatic episodes or evidence of chorioretinal scarring. Visual acuity at presentation was 0.51 or 6/19 (SE 0.096) and at follow-up 0.31 or 6/12 (SE 0.094). Nine patients experienced a recurrence during the period of observation with median time to recurrence 2.2 years (SE 0.45) and the relapse rate was 0.09/person-years. Location of lesion was predominantly within the vascular arcades (n = 44) with macular involvement in 9 patients. Most patients received clindamycin therapy (n = 34) with pyrimethamine and sulfadiazine was used for those with macula involvement.

CONCLUSIONS

Patients with ocular toxoplasmosis had fewer recurrences compared with other published series and had better visual recovery. The majority of patients received clindamycin and oral prednisolone which were well tolerated with pyrimethazine and sulfadiazine reserved for those with macula-involving disease.

Congenital central toxoplasmic chorioretinitis - case study

Congenital toxoplasmosis is a globally spread infectious disease caused by transplacental transmission of an intracellular parasitic protozoan Toxoplasma gondii. The infection can cause serious multi-organ complications, and in the case of vertical transmission, can lead up to fetal death - depending on the stage of pregnancy at the time of infection and the overall condition of the mothers immune system. Chorioretinitis, hydrocephalus and intracranial calcifications are a typical triad of symptoms associated with the disease. Toxoplasmic chorioretinitis in particular is the most common ocular manifestation. If the central retina is affected, it can cause a severe impairment of central visual acuity or lead up to blindness in the child. Prenatal screening of this disease is presently voluntary in the Czech Republic. This article reports on a case study of a toxoplasmic chorioretinitis in a newborn child observed from the active stage and the development of the affected retina over time. Further is also reported on the diagnostics and the treatment of multi-organ complications which occurred in this patient. Ophthalmologic examination was performed after diagnosis of hydrocephalus, which revealed severe changes of retina. Hydrocephalus was then properly treated. An overview of the diagnostic and therapeutic methods and the screening options available in the Czech Republic compare with other countries is also presented in the report. Key words: congenital toxoplasmosis, chorioretinitis, multi-organ complications, screening, hydrocephalus.

Toxoplasma Neuroretinitis

[Full article available at http://rimed.org/rimedicaljournal-2019-03.asp].

Clinical and Biological Factors Associated With Recurrences of Severe Toxoplasmic Retinochoroiditis Confirmed by Aqueous Humor Analysis

PURPOSE

To investigate clinical and biological factors influencing recurrences of severe toxoplasmic retinochoroiditis (TRC) confirmed by aqueous humor analysis.

DESIGN

Retrospective case series.

METHODS

Retrospective analysis of 87 subjects with severe TRC, proven by positive Goldmann-Witmer coefficient (GWC), Toxoplasma gondii (T. gondii) immunoblot, or T. gondii-specific polymerase chain reaction (PCR) in aqueous humor. Cases with immunosuppression or retinal scars without previous recorded episode were excluded. Time-dependent, clinical, treatment-related, and biological factors were explored by univariate and multivariate shared frailty survival analyses.

RESULTS

Among 44 included subjects (age, 40.4 ± 17.6 years; follow-up, 8.3 ± 2.7 years), 22 presented recurrences. There was 0.11 recurrence/patient/year and mean disease-free interval was 5.0 ± 2.9 years. The risk of recurrence was higher immediately after an episode (P < .0001). Among recurrent cases, the risk of multiple recurrences was higher when the first recurrence occurred after longer disease-free intervals (P = .046). In univariate analysis, the recurrence risk declined with higher number of intense bands on aqueous T. gondii immunoblot (P = .006), and increased when venous vasculitis was present initially (P = .019). Multivariate analysis confirmed that eyes with more intense bands on immunoblot had fewer recurrences (P = .041). There was a near-significant risk elevation after pyrimethamine/azithromycin treatment (P = .078 and P = .054, univariate and multivariate). Intravenous corticosteroid administration, oral corticosteroid administration, aqueous GWC, and T. gondii PCR did not influence recurrences (P = .12, P = .10, P = .39, and P = .96, respectively).

CONCLUSIONS

Recurrences of severe TRC are not random and may be influenced by clinical and biological factors possibly related to blood-retinal barrier alterations. These results may contribute to identifying biomarkers for TRC reactivation.

Early diagnosis and successful treatment of acquired toxoplasmosis infectious retinochoroiditis: A case report

RATIONALE

Toxoplasma gondii is distributed worldwide, infecting a large population. It can cause focal necrotic retinitis or retinochoroiditis in the human eyes and is one of the most common causes of posterior uveitis.

PATIENT CONCERNS

A 68-year-old patient with normal immunity was complained about blurred vision and black shadow in the right eye for 1 week.

DIAGNOSES

Combined Yellow-and-white bulged lesions in the fundus of the right eye with the Goldmann-Witmer coefficient = 2 and based on the serological indicators, we considered the diagnosis of T. gondii infection-induced retinochondritis.

INTERVENTIONS

Acetylspiramycin 0.4 QID × 3 weeks, concussive 20 days treatment after 3 days, for a total of 3 months, prednisone 20 mg/day with a weekly reduction of 5 mg for 1 month.

OUTCOMES

After oral acetylspiramycin, topical and systemic corticosteroids for 3 months, the retinal lesions were scarred, and inflammation of the anterior chamber and vitreum disappeared. After a 9-month follow-up, the visual acuity was 0.6, and no active lesions were observed in the fundus.

LESSONS

The immunocompetent elderly who are in contact with domestic cats may have an opportunistic infection with toxoplasmosis leading to primary retinochoroiditis. Prompt diagnosis and effective treatment can get a good clinical prognosis.

Patterns of ocular toxoplasmosis presenting at a tertiary eye care center in Korean patients

The objective of this study was to describe demographic and clinical features of ocular toxoplasmosis (OT) in Korean patients compared to those in other countries.This retrospective study comprised 46 patients diagnosed with OT. All participants were recruited at the uveitis clinic in Seoul St. Mary's Hospital.The mean age of patients was 54 years. Of 46 patients, 31 (67.4%) were females. Of all patients, 24 (52.2%) had definite eating history of wild boar meat or deer blood while 5 (10.9%) had history of close contact with cats. The most common forms of OT were vitritis (91.3%) combined with retinochoroiditis (65.2%). Active retinochoroidal lesion was located at the peripheral retina in 18 (39.1%) patients, central retina in 8 (17.4%) patients, and peripapillary retina in 4 (8.7%) patients. Seven (15.2%) cases were clinically diagnosed with typical OT without serologic evidence. Thirty-nine (84.8%) had serum IgG for toxoplasmosis. However, only 8 (17.4%) had serum IgM. In 65.2% of patients, there was no complication after treatment. The most common ocular complication was macular scar (8.7%).The present study provides demographic and clinical characteristics of OT in Korea, a low endemic area of Toxoplasma gondii. Acquired infection is the major cause of OT in Korea. Even though Korea is a low endemic area of Toxoplasma gondii, OT is a preventable and common cause of acquired infectious uveitis.

OCTA Imaging of Choroidal Neovascular Membrane Secondary to Toxoplasma Retinochoroiditis

Two patients (a 37-year-old man and a 28-year-old woman) who had choroidal neovascular membrane (CNVM) secondary to inactive toxoplasma retinochoroiditis scarring were evaluated. Multimodal imaging including fluorescein angiography, optical coherence tomography (OCT), and OCT angiography (OCTA) was used. CNVM secondary to inactive toxoplasma retinochoroiditis scarring was detected. Representative images of CNVM were demonstrated in the outer retinal layer and choriocapillary layer on OCTA. OCTA, a relatively new technique, is useful in the diagnosis of the CNVMs secondary to retinochoroiditis. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:509-511.].

Elevated Toxoplasma gondii Infection Rates for Retinas from Eye Banks, Southern Brazil

We found significantly higher incidence of Toxoplasma gondii DNA in eye bank specimens from Joinville in southern Brazil (13/15, 87%) than in São Paulo (3/42, 7%; p = 2.1 × 10E–8). PCR DNA sequence analysis was more sensitive at locus NTS2 than at locus B1; a high frequency of mixed co-infections was detected.

[Clinical and epidemiological aspects of toxoplasmosis in patients with vision problems]

INTRODUCTION

Toxoplasmosis is a worldwide disease; it can cause decreased vision or even blindness. The route of transmission in humans may vary according to the habits of the region; probably the ingestion of raw or undercooked meat is the main source of infection.

OBJECTIVE

To determine the seroprevalence of toxoplasmosis in an eye clinic, the frequency of ocular toxoplasmosis (OT) and risk habits for acquiring the infection.

MATERIALS AND METHODS

Adult patients consulting in the Retina Department of the Teaching Hospital of the National University of Asuncion, Paraguay between August and September, 2014 were included. Prior informed consent, socio-demographic and epidemiological data related to T. gondii infection were obtained. In addition a blood sample for the determination of anti T. gondii IgG antibodies by the ELISA method was taken and ophthalmologic evaluation for the diagnosis of OT was made.

RESULTS

A total of 80 patients with mean ± SD age of 53 ± 20 years were studied, with slight predominance of women (55%). The seroprevalence of toxoplasmosis was 84% (67/80) and OT was detected in 8.9% of the 67 seropositive persons. The habit of not washing vegetables with sodium hypochlorite and eat meat from wild animals was related to higher risk of infection in this population.

CONCLUSION

It is important to conduct research at the population level to establish the epidemiology of toxoplasmosis in our country. Information on prophylactic measures to prevent infection by T. gondii should be given to the population.

Bilateral maculopathy in a patient with ataxia telangiectasia

We report a case of toxoplasmosis with bilateral maculopathy in a 7-year-old boy diagnosed with ataxia telangiectasia (AT) at age 6. AT manifests as ataxia, apraxia, telangiectasia, and dysarthria. Common ophthalmologic findings in AT include fine conjunctival telangiectasia. Patients also suffer from recurrent sinopulmonary infections; however, serious opportunistic infection is rarely diagnosed. At 8 years of age he developed disseminated Toxoplasma gondii (toxoplasmosis) infection and meningoencephalitis. This ophthalmologic finding and the subsequent toxoplasmosis meningoencephalitis have not been previously reported in AT.

[Unilateral optic disc oedema as a first sign of ocular toxoplasmosis – case report]

Diagnostic procedure for unilateral optic disc oedema needs detailed medical history, careful physical examination and multiple additional tests. We present a very rare case of atypical unilateral anterior optic neuropathy as a sign of ocular toxoplasmosis in a young female. All diagnostic and therapeutic challenges have been discussed.

MHC Class I Chain-Related Gene A Polymorphisms and Linkage Disequilibrium with HLA-B and HLA-C Alleles in Ocular Toxoplasmosis

This study investigated whether polymorphisms of the MICA (major histocompatibility complex class I chain-related gene A) gene are associated with eye lesions due to Toxoplasma gondii infection in a group of immunocompetent patients from southeastern Brazil. The study enrolled 297 patients with serological diagnosis of toxoplasmosis. Participants were classified into two distinct groups after conducting fundoscopic exams according to the presence (n = 148) or absence (n = 149) of ocular scars/lesions due to toxoplasmosis. The group of patients with scars/lesions was further subdivided into two groups according to the type of the ocular manifestation observed: primary (n = 120) or recurrent (n = 28). Genotyping of the MICA and HLA alleles was performed by the polymerase chain reaction-sequence specific oligonucleotide technique (PCR-SSO; One Lambda®) and the MICA-129 polymorphism (rs1051792) was identified by nested polymerase chain reaction (PCR-RFLP). Significant associations involving MICA polymorphisms were not found. Although the MICA*002~HLA-B*35 haplotype was associated with increased risk of developing ocular toxoplasmosis (P-value = 0.04; OR = 2.20; 95% CI = 1.05–4.60), and the MICA*008~HLA-C*07 haplotype was associated with protection against the development of manifestations of ocular toxoplasmosis (P-value = 0.009; OR: 0.44; 95% CI: 0.22–0.76), these associations were not statistically significant after adjusting for multiple comparisons. MICA polymorphisms do not appear to influence the development of ocular lesions in patients diagnosed with toxoplasmosis in this study population.

The role of intravitreal trimethoprim/sulfamethoxazole in the treatment of toxoplasma retinochoroiditis

The authors evaluate the role of intravitreal trimethoprim/sulfamethoxazole in the treatment of toxoplasma retinochoroiditis (TRC) in four patients. Intravitreal injection of trimethoprim/sulfamethoxazole 1.28 mg/0.08 mL with dexamethasone 400 µg/0.1 mL was injected weekly or biweekly. After the initiation of treatment, a reduction in intraocular inflammation was observed clinically and on optical coherence tomography within 1 week. Three patients regained visual acuity of 20/20, and one patient improved to 20/40 with residual macular scarring. No evidence of retinal toxicity was noted on full-field electroretinogram. Intravitreal trimethoprim/sulfamethoxazole and dexamethasone combination may be an alternative treatment strategy in patients with TRC.

Subretinal fluid in eyes with active ocular toxoplasmosis observed using spectral domain optical coherence tomography

PURPOSE

To describe the clinical finding of subretinal fluid (SRF) in the posterior pole by spectral domain optical coherence tomography (SD-OCT) in eyes with active ocular toxoplasmosis (OT).

DESIGN

Retrospective case series.

PARTICIPANTS

Thirty-nine eyes from 38 patients with active OT [corrected]..

METHODS

Eyes with active OT which underwent SD-OCT were reviewed. SRFs in the posterior pole were further analyzed.

MAIN OUTCOME MEASURES

Presence of SRF; its accompanying features, e.g. retinal necrosis, cystoid macular edema (CME), choroidal neovascularization (CNV); and longitudinal changes of SRF, including maximum height and total volume before and after treatment.

RESULTS

SRF presented in 45.5% (or 15/33) of eyes with typical active OT and in 51.3% (or 20/39) of eyes with active OT. The mean maximum height and total volume of SRF were 161.0 (range: 23-478) µm and 0.47 (range: 0.005-4.12) mm3, respectively. For 12 eyes with SRF related to active retinal necrosis, SRF was observed with complete absorption after conventional anti-toxoplasmosis treatment. The mean duration for observation of SRF clearance was 33.8 (range: 7-84) days. The mean rate of SRF clearance was 0.0128 (range: 0.0002-0.0665) mm3/day.

CONCLUSIONS

SRF (i.e., serous retinal detachment) is a common feature in patients with active OT when SD-OCT is performed. The majority of SRF was associated with retinal necrosis and reacted well to conventional therapy, regardless of total fluid volume. However, SRF accompanying with CME or CNV responded less favorably or remained refractory to conventional or combined intravitreal treatment, even when the SRF was small in size.

Acute Central Vision Loss in an IV Drug User

This report describes the case of a 21-year-old heroin user who presented with a 6-day history of decreased vision in her right eye, preceded by 1 week of headache and tender scalp nodules, neck stiffness, and photophobia. A broad infectious workup for acute vision loss was completed, and she was ultimately presumed to have acquired toxoplasmic chorioretinitis (ocular toxoplasmosis). We review the initial workup for chorioretinitis, and the epidemiology, diagnosis, and treatment of ocular toxoplasmosis. Intravenous drug users may be at increased risk of acquired ocular toxoplasmosis.

Nonglaucomatous localized retinal nerve fiber layer defects in Behçet uveitis

PURPOSE

To describe nonglaucomatous retinal nerve fiber layer (RNFL) defects in patients with Behçet uveitis.

DESIGN

Cross-sectional study and observational case series.

METHODS

We reviewed the clinical photographs of patients with Behçet uveitis (n = 259), ocular toxoplasmosis (n = 120), and multiple sclerosis (MS)-associated uveitis (n = 40) for the presence of localized RNFL defects. Behçet patients with localized RNFL defects were invited to participate in a prospective evaluation including standard automated perimetry, spectral-domain optical coherence tomography (SD OCT), and RNFL thickness analysis. Main outcome measures were the prevalence of localized RNFL defects, perimetric and SD OCT findings, and RNFL thickness analysis.

RESULTS

Sixty-two patients with Behçet uveitis (24%) had localized RNFL defect(s) without any visible scar. Twenty patients (17%) with ocular toxoplasmosis had a localized RNFL defect associated with a retinochoroidal scar in all. None of the MS patients had a localized RNFL defect. Of the 19 patients (24 eyes) with RNFL defect associated with Behçet uveitis who returned for follow-up, there was a corollary thinning on SD OCT B-scan in all and a corresponding visual field defect in 83%. RNFL thickness analysis was within normal limits in 54%, but revealed thinning in the thickness profile scale in 46% and in the pie chart in 21%.

CONCLUSION

In Behçet uveitis, localized RNFL defects may be caused by microvascular ischemia at the optic nerve head and/or at the posterior pole and may serve as a helpful ocular diagnostic clue and an indicator of posterior pole involvement, a risk factor for poor visual prognosis.