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Frontiers in Immunology 2021infection can trigger autoreactivity by different mechanisms. In the case of ocular toxoplasmosis, disruption of the blood-retinal barrier may cause exposure of...
infection can trigger autoreactivity by different mechanisms. In the case of ocular toxoplasmosis, disruption of the blood-retinal barrier may cause exposure of confined retinal antigens such as recoverin. Besides, cross-reactivity can be induced by molecular mimicry of parasite antigens like HSP70, which shares 76% identity with the human ortholog. Autoreactivity can be a determining factor of clinical manifestations in the eye and in the central nervous system. We performed a prospective observational study to determine the presence of autoantibodies against recoverin and HSP70 by indirect ELISA in the serum of 65 patients with ocular, neuro-ophthalmic and congenital cerebral toxoplasmosis. We found systemic autoantibodies against recoverin and HSP70 in 33.8% and 15.6% of individuals, respectively. The presence of autoantibodies in cases of OT may be related to the severity of clinical manifestations, while in cases with CNS involvement they may have a protective role. Unexpectedly, anti-recoverin antibodies were found in patients with cerebral involvement, without ocular toxoplasmosis; therefore, we analyzed and proved cross-reactivity between recoverin and a brain antigen, hippocalcin, so the immunological phenomenon occurring in one immune-privileged organ (e.g. the central nervous system) could affect the environment of another (egg. the eye).
Topics: Adolescent; Adult; Amino Acid Sequence; Antigens, Protozoan; Autoantibodies; Autoantigens; Child; Child, Preschool; Cross Reactions; Female; HSP70 Heat-Shock Proteins; Hippocalcin; Host-Parasite Interactions; Humans; Infant; Infant, Newborn; Male; Middle Aged; Recoverin; Toxoplasma; Toxoplasmosis, Cerebral; Toxoplasmosis, Congenital; Toxoplasmosis, Ocular; Young Adult
PubMed: 34054794
DOI: 10.3389/fimmu.2021.606963 -
The Cochrane Database of Systematic... Apr 2013Ocular infestation with Toxoplasma gondii, a parasite, may result in inflammation in the retina, choroid, and uvea and consequently lead to complications such as... (Review)
Review
BACKGROUND
Ocular infestation with Toxoplasma gondii, a parasite, may result in inflammation in the retina, choroid, and uvea and consequently lead to complications such as glaucoma, cataract, and posterior synechiae.
OBJECTIVES
The objective of this systematic review was to assess the effects of adjunctive use of corticosteroids for ocular toxoplasmosis.
SEARCH METHODS
We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2012, Issue 9), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE, (January 1950 to October 2012), EMBASE (January 1980 to October 2012), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to October 2012), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We searched the reference lists of included studies for any additional studies not identified by the electronic searches. We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 11 October 2012.
SELECTION CRITERIA
We planned to include randomized and quasi-randomized controlled trials. Eligible trials would have enrolled participants of any age who were immunocompetent and were diagnosed with active ocular toxoplasmosis. Included trials would have compared anti-parasitic therapy plus corticosteroids versus anti-parasitic therapy alone, or different doses or times of initiation of corticosteroids.
DATA COLLECTION AND ANALYSIS
Two authors independently screened titles and abstracts retrieved from the electronic searches. We retrieved full-text articles of studies categorized as 'unsure' or 'include' after review of the abstracts. Two authors independently reviewed each full-text article. Discrepancies were resolved through discussion.
MAIN RESULTS
The electronic searches retrieved 368 titles and abstracts. We reviewed 20 full-text articles. We identified no trials eligible for inclusion in this systematic review.
AUTHORS' CONCLUSIONS
Although research has identified wide variation in practices regarding use of corticosteroids, our systematic review did not identify evidence from randomized controlled trials for the role of corticosteroids in the management of ocular toxoplasmosis. Several questions remain unanswered by well-conducted randomized trials in this context, including whether use of corticosteroids is more effective than use of anti-parasitic therapy alone, when corticosteroids should be initiated in the treatment regimen (early versus late course of treatment), and which dosage and duration of steroid use is best. These questions are easily amenable to research using a randomized controlled design and they are ethical due to the absence of evidence to support or discourage use of corticosteroids for this condition. The question of foremost importance, however, is whether they should be used as adjunct therapy (that is, additional) to anti-parasitic agents.
Topics: Adrenal Cortex Hormones; Chemotherapy, Adjuvant; Humans; Toxoplasmosis, Ocular
PubMed: 23633342
DOI: 10.1002/14651858.CD007417.pub2 -
Systematic Reviews Jul 2021Ocular toxoplasmosis (OT) is the most common cause of posterior uveitis, which leads to visual impairment in a large proportion of patients. Antibiotics and... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Ocular toxoplasmosis (OT) is the most common cause of posterior uveitis, which leads to visual impairment in a large proportion of patients. Antibiotics and corticosteroids lower the risk of permanent visual loss by controlling infection and inflammation. However, there remains disagreement regarding optimal antibiotic therapy for OT. Therefore, this systematic review and meta-analysis were performed to determine the effects and safety of existing antibiotic treatment regimens for OT.
METHODS
MEDLINE, EMBASE, The Cochrane Central Register of Controlled Trials, LILACS, WHO International Clinical Trials Registry Platform portal, ClinicalTrials.gov, and Gray Literature in Europe ("OpenGrey") were searched for relevant studies; manual searches of reference lists were performed for studies identified by other methods. All published and unpublished randomized controlled trials that compared antibiotic schemes known to be effective in OT at any dosage, duration, and administration route were included. Studies comparing antibiotics with placebo were excluded. This review followed standard methodological procedures recommended by the Cochrane group.
RESULTS
Ten studies were included in the narrative summary, of which four were included for quantitative synthesis (meta-analysis). Interventions were organized into three groups: intravitreal clindamycin versus pyrimethamine + sulfadiazine, trimethoprim + sulfamethoxazole versus other antibiotics, and other interventions. The first comparison favored intravitreal clindamycin (Mean difference (MD) = 0.10 logMAR; 95% confidence interval = 0.01 to 0.22). However, this finding lacks clinical relevance. Other outcomes showed no statistically significant differences between the treatment groups. In general, the risk of performance bias was high in evaluated studies, and the quality of the evidence found was low to very low.
CONCLUSIONS
No antibiotic scheme was superior to others, and the selection of a treatment regimen depends on multiple factors; therefore, treatment should be chosen based on safety, sulfa allergies, and availability.
Topics: Anti-Bacterial Agents; Clindamycin; Europe; Humans; Toxoplasmosis, Ocular
PubMed: 34275483
DOI: 10.1186/s13643-021-01758-7 -
Investigative Ophthalmology & Visual... Mar 2021To establish a murine model of primary acquired ocular toxoplasmosis (OT) and to investigate the immune mediator profiles in the aqueous humor (AH).
PURPOSE
To establish a murine model of primary acquired ocular toxoplasmosis (OT) and to investigate the immune mediator profiles in the aqueous humor (AH).
METHODS
C57BL/6 mice were perorally infected with Toxoplasma gondii. The ocular fundus was observed, and fluorescein angiography (FA) was performed. The AH, cerebrospinal fluid (CSF), and serum were collected before infection and at 28 days post-infection (dpi); the immune mediator levels in these samples were analyzed using multiplex bead assay.
RESULTS
Fundus imaging revealed soft retinochoroidal lesions at 14 dpi; many of these lesions became harder by 28 dpi. FA abnormalities, such as leakage from retinal vessels and dilation and tortuosity of the retinal veins, were observed at 14 dpi. Nearly all these abnormalities resolved spontaneously at 28 dpi. In the AH, interferon-γ, interleukin (IL)-1α, IL-1β, IL-6, IL-10, IL-12(p40), IL-12(p70), CCL2/MCP-1, CCL3/MIP-1α, CCL4/MIP-1β, CCL5/RANTES, and CXCL1/KC levels increased after infection. All these molecules except IL-1α, IL-4, and IL-13 showed almost the same postinfection patterns in the CSF as they did in the AH. The tumor necrosis factor α, IL-4, and IL-5 levels in the AH and CSF of the T. gondii-infected mice were lower than those in the serum. The postinfection IL-1α, IL-6, CCL2/MCP-1, CCL4/MIP-1β, and granulocyte colony-stimulating factor levels in the AH were significantly higher than those in the CSF and serum.
CONCLUSIONS
A murine model of primary acquired OT induced via the natural infection route was established. This OT model allows detailed ophthalmologic, histopathologic, and immunologic evaluations of human OT. Investigation of AH immune modulators provides new insight into OT immunopathogenesis.
Topics: Animals; Aqueous Humor; Blood-Retinal Barrier; Brain; Cerebrospinal Fluid; Cytokines; Disease Models, Animal; Fluorescein Angiography; Fluorescent Antibody Technique, Indirect; Immunohistochemistry; Immunologic Factors; Male; Mice; Mice, Inbred C57BL; Retina; Toxoplasma; Toxoplasmosis, Ocular
PubMed: 33683297
DOI: 10.1167/iovs.62.3.9 -
Asia-Pacific Journal of Ophthalmology... 2019The aim of this study was to provide a retrospective analysis of the presentation, demographics, and treatment regimens for ocular toxoplasmosis at a large tertiary...
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.
Topics: Administration, Oral; Adult; Anti-Infective Agents; Antibodies, Protozoan; Australia; DNA, Protozoan; Drug Therapy, Combination; Eye Infections, Parasitic; Female; Fluorescein Angiography; Follow-Up Studies; Fundus Oculi; Glucocorticoids; Humans; Incidence; Male; Middle Aged; Polymerase Chain Reaction; Prognosis; Retrospective Studies; Tertiary Care Centers; Tomography, Optical Coherence; Toxoplasma; Toxoplasmosis, Ocular; Visual Acuity; Young Adult
PubMed: 31369405
DOI: 10.1097/APO.0000000000000244 -
Memorias Do Instituto Oswaldo Cruz Mar 2009The influence of patient age on various features of ocular toxoplasmosis has been a subject of study for many years. The age at which Toxoplasma gondii infection occurs... (Review)
Review
The influence of patient age on various features of ocular toxoplasmosis has been a subject of study for many years. The age at which Toxoplasma gondii infection occurs in different populations is related to socioeconomic factors and studies suggest that ocular toxoplasmosis is a more severe disease at the extremes of age. The prevalence of ocular involvement is markedly different between individuals with congenital and those with post-natally acquired infections. Even among those with post-natally acquired infections, age influences the risk and timing of ocular involvement. The severity of toxoplasmic retinochoroiditis (in terms of lesion size, location and associated inflammation) is also affected by patient age at the time of initial infection or recurrence. The risk of recurrent toxoplasmic retinochoroiditis is influenced by age at the time of initial infection and age at most recent episode of active disease. Understanding of relationships between ocular toxoplasmosis and patient age is incomplete; evidence has often been indirect and in some cases conflicting. The influence of patient age on ocular toxoplasmosis should be studied in a systematic manner to provide a better understanding of disease mechanisms and to provide clinical information that can used to establish better strategies for disease treatment and prevention.
Topics: Age Factors; Chorioretinitis; Female; Humans; Pregnancy; Prevalence; Recurrence; Risk Factors; Toxoplasmosis, Ocular
PubMed: 19430663
DOI: 10.1590/s0074-02762009000200031 -
Journal of Ophthalmic & Vision Research Oct 2011The correlation between myopia and intraocular inflammation has rarely been explored. The aim of this article is to review myopic changes induced by inflammatory...
The correlation between myopia and intraocular inflammation has rarely been explored. The aim of this article is to review myopic changes induced by inflammatory diseases and inflammatory diseases related to myopia, followed by a discussion on inflammatory choroidal neovascularization. Clinical cases are used to illustrate these conditions. The review does not include inflammatory conditions caused by surgical interventions employed for treatment of myopia. Uveitic conditions that can induce a myopic shift include sclero-choroidal inflammation, lens induced myopia due to steroid cataracts, juvenile idiopathic arthritis (JIA) induced myopia, and transient drug induced myopia due to sulfonamides and acetazolamide used for treatment of ocular toxoplasmosis and inflammatory cystoid macular edema, respectively. Most inflammatory conditions related to myopia are conditions involving the choriocapillaris. These include multifocal choroiditis and/or punctate inner choroiditis, multiple evanescent white dot syndrome and acute idiopathic blind spot enlargement. It can be hypothesized that fragility of the choriocapillaris due to particular anatomic changes due to myopia, together with unknown immunogenetic factors predispose myopic eyes to primary inflammatory choriocapillaropathies.
PubMed: 22454750
DOI: No ID Found -
International Medical Case Reports... 2021We report three cases of optic nerve toxoplasmosis, an unusual form of ocular toxoplasmosis. In one patient, the optic nerve involvement occurred in an eye with a...
We report three cases of optic nerve toxoplasmosis, an unusual form of ocular toxoplasmosis. In one patient, the optic nerve involvement occurred in an eye with a toxoplasmic chorioretinal scar and choroidal neovascularization in the supramacular area, subretinal fibrosis, and pigment epithelium detachment. The other two patients had papilledema without healed or active chorioretinal lesions, but both had retinal hemorrhage and macular involvement. The diagnosis was based on clinical examination and elevated serum toxoplasma antibodies. Optical coherence tomography helped uncover the structural chorioretinal changes. All patients were treated with a combination of oral antitoxoplasmic drugs, oral prednisone, and intravitreal injection of bevacizumab. Visual acuity improved in all of them. Optic nerve involvement in ocular toxoplasmosis must be considered when papilledema occurs both in isolation and/or in the presence of an active or scarred chorioretinal lesion.
PubMed: 34588823
DOI: 10.2147/IMCRJ.S332147 -
Cureus Jan 2021We present a case of a 74-year-old woman with chronic lymphocytic leukemia (CLL) who presented with unilateral blurry vision that had progressively worsened over a few...
We present a case of a 74-year-old woman with chronic lymphocytic leukemia (CLL) who presented with unilateral blurry vision that had progressively worsened over a few weeks. Ophthalmic examination revealed unilateral anterior chamber, vitreous body inflammation along with retinal infiltration which was initially diagnosed with posterior uveitis. Analysis of vitreous fluid aspiration was negative for bacteria, fungal and viral etiologies. Despite the broad-spectrum intraocular antibiotics, her vision continued to decline, and she later developed retinal detachment. Cytology for lymphoma was negative. However, polymerase chain reaction (PCR) with internal transcribed spacer-specific (ITS) primer set detected , and the patient was diagnosed with intraocular toxoplasmosis. Treatment with systemic clindamycin, pyrimethamine, leucovorin, prednisone, and topical clindamycin for four weeks successfully prevented further ocular damage.
PubMed: 33659144
DOI: 10.7759/cureus.13014 -
The British Journal of Ophthalmology Dec 1996
Review
Topics: AIDS-Related Opportunistic Infections; Animals; Central Nervous System Diseases; HIV Infections; Humans; Immunocompromised Host; Recurrence; Toxoplasma; Toxoplasmosis, Ocular
PubMed: 9059278
DOI: 10.1136/bjo.80.12.1099