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Ocular Immunology and Inflammation Feb 2022To present a narrative review about ocular toxoplasmosis epidemiology, disease burden and prevalent African parasitic strains. (Review)
Review
PURPOSE
To present a narrative review about ocular toxoplasmosis epidemiology, disease burden and prevalent African parasitic strains.
METHODS
An initial search for MeSH terms was conducted with a posterior advanced search in two electronic databases. Full text reading was performed.
RESULTS
Animal African studies have identified type II, type III, Africa 1, and Africa 3 strains. Seroprevalence varies from 6.4% to 74.5%. Nevertheless, there is a scarcity of epidemiology and serotyping information about ocular toxoplasmosis. African studies have demonstrated that uveitis patients present high frequencies of ocular toxoplasmosis. There is a lack of studies describing specific clinical characteristics, which can be related, to environmental and socioeconomic factors, parasite serotype and genotype, and genetic susceptibility of the host.
CONCLUSION
As has more virulent strains in the Southern hemisphere, it is relevant to determine African strain types and the correlation between the infecting strains and the clinical manifestations.
Topics: Africa; Animals; Genotype; Humans; Seroepidemiologic Studies; Toxoplasma; Toxoplasmosis, Ocular
PubMed: 32976046
DOI: 10.1080/09273948.2020.1801761 -
PLoS Neglected Tropical Diseases Dec 2020Infections with the protozoan parasite Toxoplasma gondii are frequent, but one of its main consequences, ocular toxoplasmosis (OT), remains poorly understood. While its... (Review)
Review
Infections with the protozoan parasite Toxoplasma gondii are frequent, but one of its main consequences, ocular toxoplasmosis (OT), remains poorly understood. While its clinical description has recently attracted more attention and publications, the underlying pathophysiological mechanisms are only sparsely elucidated, which is partly due to the inherent difficulties to establish relevant animal models. Furthermore, the particularities of the ocular environment explain why the abundant knowledge on systemic toxoplasmosis cannot be just transferred to the ocular situation. However, studies undertaken in mouse models have revealed a central role of interferon gamma (IFNγ) and, more surprisingly, interleukin 17 (IL17), in ocular pathology and parasite control. These studies also show the importance of the genetic background of the infective Toxoplasma strain. Indeed, infections due to exotic strains show a completely different pathophysiology, which translates in a different clinical outcome. These elements should lead to more individualized therapy. Furthermore, the recent advance in understanding the immune response during OT paved the way to new research leads, involving immune pathways poorly studied in this particular setting, such as type I and type III interferons. In any case, deeper knowledge of the mechanisms of this pathology is needed to establish new, more targeted treatment schemes.
Topics: Eye; Eye Diseases; Humans; Toxoplasma; Toxoplasmosis
PubMed: 33382688
DOI: 10.1371/journal.pntd.0008905 -
Acta Tropica Jan 2022Toxoplasma gondii is a widespread protozoan parasite infecting approximately one third of the world population. After proliferation of tachyzoites during the acute... (Review)
Review
Toxoplasma gondii is a widespread protozoan parasite infecting approximately one third of the world population. After proliferation of tachyzoites during the acute stage, the parasite forms tissue cysts in various anatomical sites and establishes chronic infection. Nowadays the nature of the interplay between the protozoan and its human host remains elusive. This is clearly evident in ocular toxoplasmosis, in which the parasite establishes an ambivalent relationship with the eye, manipulating the immune response and inducing variable initial lesions and further relapses. This review will focus on epidemiology and environmental, parasite and host related risk factors, clinical manifestations and laboratory findings, treatment and prophylaxis approaches in ocular toxoplasmosis. An image collection of patients referred to the Unit of Ophthalmology of Pisa's Hospital will be presented, too.
Topics: Humans; Toxoplasma; Toxoplasmosis, Ocular
PubMed: 34699742
DOI: 10.1016/j.actatropica.2021.106180 -
American Journal of Ophthalmology Jun 2015
Topics: Chorioretinitis; Disease Outbreaks; Female; Humans; Infectious Disease Transmission, Vertical; Male; Toxoplasma; Toxoplasmosis, Ocular
PubMed: 25956461
DOI: 10.1016/j.ajo.2015.04.005 -
Frontiers in Immunology 2024Ocular toxoplasmosis (OT) is an intraocular infection caused by the parasite OT is manifested as retinal choroiditis and is the most common infectious cause of... (Review)
Review
Ocular toxoplasmosis (OT) is an intraocular infection caused by the parasite OT is manifested as retinal choroiditis and is the most common infectious cause of posterior uveitis. Invasion of the retina by leads to disruption of the blood-ocular barrier and promotes the migration of immune cells to the ocular tissues. Cytokines such as IFN-γ and IL-1β are effective for controlling parasite growth, but excessive inflammatory responses can cause damage to the host. In this review, we will discuss in detail the latest advances in the immunopathology and treatment of OT.
Topics: Humans; Toxoplasmosis, Ocular; Toxoplasma; Animals; Cytokines
PubMed: 38799473
DOI: 10.3389/fimmu.2024.1403025 -
Rhode Island Medical Journal (2013) Mar 2019[Full article available at http://rimed.org/rimedicaljournal-2019-03.asp].
[Full article available at http://rimed.org/rimedicaljournal-2019-03.asp].
Topics: Adult; Female; Humans; Retinitis; Toxoplasma; Toxoplasmosis, Ocular; Visual Acuity
PubMed: 30823700
DOI: No ID Found -
Arquivos Brasileiros de Oftalmologia 2022Toxoplasma gondii infection can cause ocular manifestations after acquired and congenital disease. We report two cases of symptomatic congenital toxoplasmosis with...
Toxoplasma gondii infection can cause ocular manifestations after acquired and congenital disease. We report two cases of symptomatic congenital toxoplasmosis with ocular involvement in non-twin siblings, with a 2-year interval between pregnancies. Vertical transmission of toxoplasmosis in successive pregnancies, which was once considered impossible, is now found to be plausible even in immunocompetent subjects.
Topics: Pregnancy; Female; Humans; Toxoplasmosis, Congenital; Toxoplasmosis, Ocular; Siblings; Infectious Disease Transmission, Vertical; Eye; Toxoplasma
PubMed: 35170636
DOI: 10.5935/0004-2749.20220079 -
Redox Biology Nov 2023Toxoplasmosis is a major infectious disease, affecting approximately one-third of the world's population; its main clinical manifestation, ocular toxoplasmosis (OT), is...
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 Fe, 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.
Topics: Animals; Mice; Humans; Toxoplasmosis, Ocular; Ferroptosis; Toxoplasma; Chorioretinitis; Retina; Iron
PubMed: 37738924
DOI: 10.1016/j.redox.2023.102890 -
Ophthalmology. Retina Nov 2022
Topics: Humans; Toxoplasmosis, Ocular; Retinal Diseases
PubMed: 36100532
DOI: 10.1016/j.oret.2022.08.008 -
Current Opinion in Ophthalmology Nov 2015The purpose of this review was to provide an overview of current data on antibiotic prophylaxis in ocular toxoplasmosis. (Review)
Review
PURPOSE OF REVIEW
The purpose of this review was to provide an overview of current data on antibiotic prophylaxis in ocular toxoplasmosis.
RECENT FINDINGS
Studies showing the prophylactic effect of long-term antibiotics are discussed. Prophylaxis seems to be justified in patients with a high risk of recurrence because of antibiotic's potential side-effects. Therefore, predisposing factors leading to a higher risk of recurrence and the time period during which an antibiotic prophylaxis is most appropriate are reviewed. Finally, a patient-individualized treatment recommendation is summarized.
SUMMARY
In the current literature, two prospective, randomized case-control studies exist, which show the protective effect of an antibiotic prophylaxis. Hematologic, gastrointestinal and dermatologic complications are potential side-effects. Especially during the first year after suffering a recurrence, an antibiotic prophylaxis seems to be justified. The risk of a recurrence is inter alia influenced by the duration of the disease, the immune status of the host and the patient's age. Therefore, an antibiotic prophylaxis should be considered for patients who have recently been infected with ocular toxoplasmosis, for middle-aged and elderly patients and patients with a compromised immune system. This should be discussed with each patient individually, especially if the lesion is close to the macula.
Topics: Age Distribution; Anti-Bacterial Agents; Antibiotic Prophylaxis; Humans; Patient Selection; Risk Factors; Toxoplasmosis, Ocular
PubMed: 26367087
DOI: 10.1097/ICU.0000000000000205