Ocular Toxoplasmosis after Exposure to Wild Game.

PURPOSE: To describe eight patients with toxoplasma retinochoroiditis following exposure to wild game. METHODS: Retrospective, multicenter case series. RESULTS: Eight men, aged 29 to 71 (mean, 56 years), developed toxoplasmic retinochoroiditis after hunting and/or consuming wild game in the United States, including seven deer and one bear. Five patients developed the disease after eating undercooked game meat, while three developed ocular findings after cleaning hunted animals. Seven patients were healthy prior to exposure. LogMAR visual acuity at presentation was 0.697 ± 0.745, improving to 0.256 ± 0.335 by last follow-up. Disease complications developed in five (62.5%) patients, of which recurrence of retinochoroiditis was the most common. CONCLUSIONS: Contact with wild game is a potential source of primary ocular toxoplasmosis in immunocompetent adults. Hunters and consumers of rare game are at risk of serious ocular disease and appropriate contact precautions and cooking may reduce this complication.

Pathogenesis of ocular toxoplasmosis.

Ocular toxoplasmosis is a retinitis -almost always accompanied by vitritis and choroiditis- caused by intraocular infection with Toxoplasma gondii. Depending on retinal location, this condition may cause substantial vision impairment. T. gondii is an obligate intracellular protozoan parasite, with both sexual and asexual life cycles, and infection is typically contracted orally by consuming encysted bradyzoites in undercooked meat, or oocysts on unwashed garden produce or in contaminated water. Presently available anti-parasitic drugs cannot eliminate T. gondii from the body. In vitro studies using T. gondii tachyzoites, and human retinal cells and tissue have provided important insights into the pathogenesis of ocular toxoplasmosis. T. gondii may cross the vascular endothelium to access human retina by at least three routes: in leukocyte taxis; as a transmigrating tachyzoite; and after infecting endothelial cells. The parasite is capable of navigating the human neuroretina, gaining access to a range of cell populations. Retinal Müller glial cells are preferred initial host cells. T. gondii infection of the retinal pigment epithelial cells alters the secretion of growth factors and induces proliferation of adjacent uninfected epithelial cells. This increases susceptibility of the cells to parasite infection, and may be the basis of the characteristic hyperpigmented toxoplasmic retinal lesion. Infected epithelial cells also generate a vigorous immunologic response, and influence the activity of leukocytes that infiltrate the retina. A range of T. gondii genotypes are associated with human ocular toxoplasmosis, and individual immunogenetics -including polymorphisms in genes encoding innate immune receptors, human leukocyte antigens and cytokines- impacts the clinical manifestations. Research into basic pathogenic mechanisms of ocular toxoplasmosis highlights the importance of prevention and suggests new biological drug targets for established disease.

Disease of the Year 2019: Ocular Toxoplasmosis in HIV-infected Patients.

Ocular toxoplasmosis (OT) may be an initial manifestation of acquired immunodeficiency syndrome (AIDS) in human immunodeficiency virus (HIV)-infected patients. OT has different clinical manifestations and can mimic other intraocular infections. Clinical findings may show single or multifocal retinochoroidal lesions or panuveitis. Atypical presentations are associated with extensive uni- or bilateral areas of retinal necrosis. OT lesions not associated with preexisting retinochoroidal scars are usually due to acquired rather than congenital infection. When CD4+ T cell counts are <100 c/uL, vitritis is frequently mild. Isolated anterior uveitis has been reported in single cases. Positive immunoglobulin M (IgM) antibodies are rare but their presence can support the diagnosis. As atypical presentations of OT are common, anterior chamber puncture for multiplex polymerase chain reaction amplification of infectious DNA should be considered, as early diagnosis and treatment can prevent massive tissue destruction and preserve vision. This review provides an overview of OT in HIV-infected patients.

Reacción en cadena de la polimerasa en fluidos oculares en las formas atípicas de uveítis posterior / Polymerase chain reaction in ocular fluids in atypical forms of posterior uveitis

RESUMEN La toxoplasmosis ocular es la causa de uveítis posterior más frecuente en muchos países. El diagnóstico correcto se basa principalmente en las características clínicas de la enfermedad; pero en las formas de uveítis posterior atípicas se necesita el apoyo del laboratorio para confirmar el diagnóstico y no indicar tratamientos inapropiados. Se resalta el valor de la reacción en cadena de la polimerasa en fluidos oculares en pacientes con títulos serológicos en suero positivos para toxoplasma y presentaciones atípicas de uveítis posterior. Se presenta un caso clínico de una paciente con toxoplasmosis sistémica, confirmada con títulos serológicos en suero positivos, quien concomitó con uveítis posterior bilateral sin características típicas de toxoplasmosis ocular, en la cual la reacción en cadena de la polimerasa de fluidos oculares fue esencial en el diagnóstico. La reacción en cadena de la polimerasa en fluidos oculares constituye una herramienta inequívoca en el diagnóstico correcto de las formas atípicas de uveítis posteriores(AU)

ABSTRACT Ocular toxoplasmosis is the most frequent cause of posterior uveitis in many countries. Correct diagnosis is mainly based on the clinical characteristics of the disease, but in atypical forms of posterior uveitis laboratory support is required to confirm the diagnosis and not indicate inappropriate treatments. Evidence is provided of the usefulness of polymerase chain reaction in ocular fluids from patients with serum serological titers positive for toxoplasma and atypical presentations of posterior uveitis. A clinical case is presented of a female patient with systemic toxoplasmosis confirmed by positive serum serological titers and concomitant bilateral posterior uveitis without typical features of ocular toxoplasmosis, in which polymerase chain reaction in ocular fluids was essential for the diagnosis. Polymerase chain reaction in ocular fluids is an unequivocal tool for the correct diagnosis of atypical forms of posterior uveitis(AU)

Toxoplasma retinitis following intravitreal injection of triamcinolone acetonide: A case report and review of literature.

The aim of this study was to report a case of atypical toxoplasma retinochoroiditis following intravitreal triamcinolone acetonide (IVTA) injection and to review the literature pertaining to toxoplasma retinochoroiditis following intravitreal injection of corticosteroid. Clinical data were collected from a 64-year-old male who developed toxoplasma retinitis 2 months after IVTA. A review of the literature was conducted to identify additional reports on similar cases. A 64-year-old male, known diabetic with nonproliferative diabetic retinopathy in both the eyes and optic atrophy in the left eye, presented with atypical retinitis inferior to the disc following IVTA. Real-time polymerase chain reaction and serology confirmed the toxoplasma etiology, and the patient was started on anti-toxoplasma therapy along with oral corticosteroid leading to regression of the lesion by 3 months. A high index of suspicion and proper microbiological diagnosis with appropriate antimicrobial therapy can aid in the management of toxoplasma retinochoroiditis following intravitreal injection of corticosteroid.

[Uveitis treated with biotherapy and/or DMARD: Analysis from the French Pharmacovigilance Study Base]. / Uvéites sous biothérapies et/ou DMARDs en rhumatologie : analyse de la base de données déclarative de la pharmacovigilance nationale française.

PURPOSE: To report the characteristics of uveitis cases occurring while on biologic therapy or disease-modifying antirheumatic drugs (DMARDs) reported to the French national pharmacovigilance database. METHODS: All the uveitis cases occurring in patients with chronic rheumatologic diseases, chronic inflammatory intestinal diseases or connective tissue diseases, while treated with DMARDs and/or biologic therapies between 2000 and 2015 and reported to the French National Pharmacovigilance Database were collected. RESULTS: During the study period, 32 cases of uveitis were reported (15 men, 17 women). Two patients were treated with one DMARD alone, 24 with biologic therapy alone, and six with both treatments. Anterior uveitis was diagnosed in 19 patients (8 cases were bilateral); intermediate uveitis was found (unilaterally) in one patient; posterior and diffuse uveitis occurred in 5 and 2 cases respectively. Five cases were inconclusive with regard to the anatomical type of uveitis. The uveitis was of infectious origin in 5 cases: 2 toxoplasmosis, 2 herpes virus and 1 tuberculosis. In the 27 other cases, it was not possible to state whether the uveitis was associated with the underlying disease (uncontrolled) or a side effect of the biologic/DMARD treatments. The occurrence of the uveitis led to 9 switches in biologic therapy and 13 discontinuations of treatment (8 complete discontinuations, 5 discontinuations only until uveitis remission was obtained). In 4 cases, the treatments were not modified. The database does not specify the ultimate course or rheumatologic disease activity at the time of the uveitis. CONCLUSIONS: The presence of uveitis while on biologic therapy must not be taken to indicate a therapeutic failure, especially if the ocular manifestation is isolated. In the case of uveitis occurring in patients treated with biologic therapies and/or DMARDs, infectious complications should be ruled out.

The Impact of Short-Term, Intensive Antifolate Treatment (with Pyrimethamine and Sulfadoxine) and Antibiotics Followed by Long-Term, Secondary Antifolate Prophylaxis on the Rate of Toxoplasmic Retinochoroiditis Recurrence.

PURPOSE: To assess the impact of intensive antifolate treatment, followed by secondary antifolate prophylaxis (A-SP) on the recurrence rate of toxoplasmic retinochoroiditis (TRC). To investigate whether there are any other factors potentially predisposing for recurrence. MATERIAL AND METHODS: A total of 637 medical records of TRC patients, who had been treated in the years 1994-2013 were reviewed. All patients were treated with pyrimethamine /sulfadoxine one 25mg/500mg tablet daily (P/S 25/500mg) for 21 days with a double loading dose for the first two days. From Day 2 the patients also received prednisone at a starting dose of 40mg and spiramycine 3 million IU three times daily, given for 10 days followed by azithromycin 500mg once daily for another 6 days. The analysis of the recurrence rate involved 352 patients who had completed 6-month secondary prophylaxis (P/S one 25 mg/500mg tablet twice a week). RESULTS: When secondary antifolate prophylaxis (A-SP) was instituted immediately after the treatment for TRC, the probability of 3-year recurrence-free survival after the first course of A-SP was 90.9%. A recurrence was most likely approximately 3.5 years after the first treatment. A univariate Cox regression model demonstrated that a risk for recurrence was 2.82 times higher (p = 0.02) in patients with retinal scars. In the multivariate analysis, the risk for recurrence was 2.41 higher (p = 0.06). In patients with haemorrhagic lesions the risk for recurrence was lower, aRR = 0.17 (approaching borderline statistical significance p = 0.08). CONCLUSIONS: With the institution of A-SP of immediately after the intensive treatment for TRC, i.e. when a reactivation was most likely, there was no recurrence during A-SP. Following A-SP the recurrence rates were low and recurrence-free periods tended to be longer. The treatment regimen employed had a beneficial effect on the recurrence interval as it reduced and delayed the highest probability of recurrence.

Epidemiological and serological profiles of ocular toxoplasmosis in the municipality of Natal, northeastern Brazil.

BACKGROUND: Toxoplasma gondii is the main culprit in most cases of infectious uveitis, in both acute and recurrent cases of congenital toxoplasmosis and acquired infections. METHODS: The ocular toxoplasmosis was evaluated in patients at the the reference unit in ophthalmology, in Rio Grande do Norte State, determining the risk factors, and the epidemic, serological and clinical profiles. The production of IgM and IgG antibodies to T. gondii was evaluated by microparticle enzyme immunoassay (MEIA). The same patients diagnosed with fundoscopic alterations have been subjected to the fundus photography procedure. RESULTS: Of the 116 patients with positive serology, 66 patients had bilateral ocular damage and 38 patients showed a higher frequency of lesions of type I. The epidemiological investigation showed that direct contact with cats, the consumption of raw or undercooked meat and direct contact with soil are factors not related to ocular toxoplasmosis development. The characterization of the sample was significant for patients aged 31-40 years. CONCLUSIONS: Ocular toxoplasmosis is widely distributed in Natal and other cities in Rio Grande do Norte state, with special relevance for bilateral lesions in 56.9% of the patients assessed, the most frequent being type I with intraocular disposition in the macula.

Risk of reactivation of toxoplasmic retinitis following intraocular procedures without the use of prophylactic therapy.

BACKGROUND/AIMS: Toxoplasmic retinochoroiditis is the commonest known cause of posterior uveitis worldwide and reactivation is unpredictable. Based on results from one study, the authors proposed that antitoxoplasmic therapy should be initiated as prophylaxis for intraocular surgery in patients with toxoplasmic scars. The aim of this study is to analyse the risk of toxoplasmic retinochoroiditis reactivation following intraocular procedures. METHODS: Retrospective analysis of the medical records of a total of 69 patients who underwent intraocular surgery and presented with toxoplasmic retinochoroiditis scars. RESULTS: No patient received prophylactic antitoxoplasmic therapy. Reactivation following the surgical procedure occurred in four cases, with one at 3 months and the others respectively at 13, 14 and 17 months. CONCLUSIONS: Our study shows that intraocular surgery did not result in a significant reactivation rate of toxoplasmic retinochoroiditis in the absence of preoperative prophylactic antitoxoplasmic therapy.

Ocular toxoplasmosis past, present and new aspects of an old disease.

Ocular toxoplasmosis (OT) is considered the most frequent form of infectious posterior uveitis and is caused by the protozoan parasite Toxoplasma gondii. The resulting vision loss frequently incapacitates patients and places a considerable socio-economic burden on societies in particular in developing countries. Although, toxoplasmic retinochoroiditis is a world-wide phenomenon stark regional differences with regard to prevalence and presumably route of infection exist. This review will discuss our current clinical understanding of OT including typical and atypical manifestations, patient characteristics which influence the course of disease and treatment options. Even though, congenital and acquired OT are not regarded as separate entities, certain differences exist, which will be assessed and evaluated in detail. A strong focus is laid on the disease causing parasite T. gondii, since solving the mystery of OT aetiology and the development of improved therapies will not be possibly with clinical science alone, but rather requires a precise understanding of parasitological and immunological pathomechanisms. Additionally, the biology and genetics of T. gondii form the foundation for novel and sophisticated diagnostic methods. Scientific advances in the recent years have shed some light on the different role of T. gondii strains with regard to OT manifestation and severity of disease. Genetic and environmental factors influencing OT will be presented and commonalities between OT and toxoplasmic encephalitis will be briefly discussed. Furthermore, the laboratory tools to study OT are crucial in our understanding of OT. In vivo and in vitro experimental approaches will be summarised and evaluated extensively. Finally, a brief outlook is given in which direction OT research should be headed in the future.

Is reactivation of toxoplasmic retinochoroiditis associated to increased annual rainfall?

BACKGROUND: Reactivation of toxoplasmic retinochoroiditis is the most frequent form of uveitis in Misiones, Argentina. Fluctuations in the number of patients consulting with this type of uveitis were detected during the last decade. Since the province was consecutively exposed to rainy and dry periods over the last years, we decided to explore whether a relationship between reactivation of toxoplasmic retinochoroiditis and rain might be established according to the data registered during the 2004-2010 period. RESULTS: The frequency of toxoplasmic reactivation episodes increases when precipitation increases (mostly in second and fourth trimesters of each year). Analysis of the independent variables demonstrates that precipitation is a significant predictor of the frequency of reactivation episodes. Although registered toxoplasmic reactivations were more frequent during the third trimester of the year, the association between the third trimester and the reactivation episodes did not reach statistical significance. CONCLUSION: Prolonged and intense rainfall periods were significantly associated with the reactivation of toxoplasmic retinochoroiditis. Changes promoted by this climatic condition on both the parasite survival in the soil as well as a putative effect on the host immune response due to other comorbidities are discussed.

[Congenital toxoplasmosis: long-term ophthalmologic follow-up praised by patients]. / Toxoplasmose congénitale; le suivi ophtalmologique à long terme plébiscité par les patients.

INTRODUCTION: Ocular lesions of congenital toxoplasmosis may occur and relapse unpredictably even a long time after birth. There is no consensus concerning the necessity or timing of ophthalmologic follow-up for these patients. We surveyed adults with congenital toxoplasmosis followed regularly since birth, in order to learn their perceptions of this follow-up. The goal of this study was to provide doctors with patient-reported information on how they perceived the long-term monitoring of their disease. METHODS: Enrolled patients were given a two-question questionnaire addressing the way they perceived the long-term follow-up and their attitudes toward continuing it. Eligible patients had to be 18 years or older and to have undergone ophthalmologic follow-ups, including funduscopy, every year since birth. The last ophthalmologic examination had to be within one year of the patient's inclusion in the study. RESULTS: Of the 102 patients finally included in the study, 98% stated that the follow-up was useful and 92% reassuring. Among the 11% of patients who found the follow-ups frightening, the proportion of patients with low visual acuity and low score on the visual function test was significantly higher than among the others. All patients except two wished to continue with regular follow-up. CONCLUSION: Without general agreement or guidelines on how patients with congenital toxoplasmosis should be monitored, the patient's wishes are important in making a decision. Our study brought out a clear fact; the majority of patients found long-term follow-up useful and reassuring and wished to continue.

[Ocular toxoplasmosis developed after liver transplantation]. / Karaciger Transplantasyonu Sonrasi Gelisen Oküler Toksoplazmoz.

Ocular toxoplasmosis after solid organ transplantation occurs usually within the first three months of primary infection or reactivation of latent infection. There are a few reports of ocular toxoplasmosis following liver transplantation in the literature, however, no reports were detected in the national data. In this report a 35-year-old female patient diagnosed as ocular toxoplasmosis following reactivation in the second year after liver transplantation, was presented. The case was successfully treated with trimethoprim/sulfamethoxazole and clindamycin. This case was presented to emphasize late presentation of toxoplasmosis in transplantation patients and to withdraw attention to the importance of serological investigations done before transplantation.

Increased frequency of anti-retina antibodies in asymptomatic patients with chronic t. gondii infection.

PURPOSE: To search for anti-retina antibodies that serve as markers for eye disease in uveitis. MATERIALS AND METHODS: Stored sera from patients with uveitis, ocular toxoplasmosis (n = 30) and non-infectious, immune-mediated uveitis (n = 50) and from asymptomatic individuals who were positive (n = 250) and negative (n = 250) for anti-Toxoplasma antibodies were tested. Serum anti-retina IgG was detected by an optimized ELISA using a solid-phase whole human retina extract, bovine S-antigen or interphotoreceptor retinoid-binding protein. RESULTS: Uveitis patients showed a higher mean reactivity to whole human retina extract, interphotoreceptor retinoid-binding protein and S-antigen in comparison to the asymptomatic population. These findings were independent of the uveitis origin and allowed the determination of the lower anti-retina antibody cut-off for the three antigens. Asymptomatic anti-Toxoplasma serum-positive individuals showed a higher frequency of antihuman whole retina extract antibodies in comparison to asymptomatic anti-Toxoplasma serum-negative patients. The bovine S-antigen and interphotoreceptor retinoid-binding protein ELISAs also showed a higher mean reactivity in the uveitis groups compared to the asymptomatic group, but the observed reactivities were lower and overlapped without discrimination. CONCLUSION: We detected higher levels of anti-retina antibodies in uveitis patients and in a small fraction of asymptomatic patients with chronic toxoplasmosis. The presence of anti-retina antibodies in sera might be a marker of eye disease in asymptomatic patients, especially when whole human retina extract is used in a solid-phase ELISA.

Toxoplasmosis ocular. Presentación de dos casos / Ocular toxoplasmosis: presentation of a case

La toxoplasmosis ocular es la causa más frecuente de uveítis posterior de etiología conocida, caracterizada por recurrencias que conllevan a una pérdida significativa de la visión. La manifestación ocular más frecuente es la coriorretinitis, tanto en una primoinfección como en la recidiva de una forma congénita. Se presentan dos casos que acuden a la consulta de oftalmología de la clínica José Martí Ballenita, en Ecuador, por pérdida brusca de visión. A los mismos se les diagnosticó esta enfermedad. El desempeño del oftalmólogo en el diagnóstico precoz de la misma es de vital importancia, para la aplicación de la terapia, tipo de droga a utilizar y duración del tratamiento de forma individualizada con las drogas de elección, y lograr así una consecuente rehabilitación visual...(AU)

Long-term outcome of children with congenital toxoplasmosis.

OBJECTIVE: Maternal toxoplasmosis infection acquired during pregnancy carries significant risk of fetal damage. We aimed to assess the long-term outcome of children and young adults with congenital toxoplasmosis diagnosed and treated in utero. STUDY DESIGN: This was a 20 year prospective study (1985-2005). All mothers received spiramycin, alone or associated with pyrimethamine-sulfadoxine, and underwent amniocentesis and monthly ultrasound screening. Infected children were followed every 3-6 months. RESULTS: Of 666 liveborn children (676 mothers), 112 (17%) had congenital toxoplasmosis. Among these, 107 were followed up for 12-250 months: 79 were asymptomatic (74%) and 28 had chorioretinitis (26%). Only 1 child had a serious neurological involvement. CONCLUSION: The percentage of chorioretinitis in treated children depends on length of follow-up, but this complication occurs mainly before the age of 5 years and almost always before the age of 10 years. Visual impairment was infrequently severe, and outcome appears consistently good. Long-term follow-up is recommended to monitor ocular and neurological prognosis, whatever the practical difficulties.