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

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

Comparison of real-time PCR and nested PCR for toxoplasmosis diagnosis in toxoplasmic retinochoroiditis patients.

BACKGROUNDS: PCR is a proper technique that significantly improves toxoplasmosis diagnosis. However, a more sensitive technique is required. This study compared real-time PCR with nested PCR using B1, SAG-4, and MAG-1 bradyzoite genes to diagnose toxoplasmosis in toxoplasmic retinochoroiditis patients. METHODS: Blood samples were collected from 10 patients with active toxoplasmic chorioretinal lesions and 10 healthy individuals. Blood samples including peripheral blood mononuclear cells (PBMCs), serum and whole blood samples were used for DNA extraction. Serum was also used to detect anti-toxoplasma IgG and IgM antibodies. Nested PCR and real-time PCR were performed using B1, SAG-4, and MAG-1 target genes. RESULTS: Five (50%) out of the 10 patients were tested positive for toxoplasmosis with nested PCR using the PBMC samples. All the five patients tested positive with nested PCR were also tested positive for toxoplasmosis with real-time PCR using the PBMC samples. The real-time PCR results demonstrated that 9(90%) out of the 10 patients were positive based on B1 and the remaining one (10%) was positive only based on MAG-1. In general, of the patients, five (50%) were positive using SAG-4 and three (30%) were positive in term of MAG-1 using PBMCs with real-time PCR. CONCLUSION: It appears that PBMC samples have the best performance as the PCR extraction method and are a good source for toxoplasmosis diagnosis. The use of B22 and B23 target genes due to their high sensitivity and specificity along with bradyzoite genes are recommended for toxoplasmosis diagnosis using PBMC samples with real-time PCR.

Chorio-retinal toxoplasmosis: treatment outcomes, lesion evolution and long-term follow-up in a single tertiary center.

BACKGROUND: Ocular toxoplasmosis is a common cause of ocular inflammation worldwide. The aim of this study is to characterize the clinical outcomes and lesion evolution of patients with ocular toxoplasmosis and to compare the primary and reactivation subgroups. METHODS: A retrospective population-based cohort study at one uveitis-specialized tertiary referral center. Patients presenting with active ocular toxoplasmosis between the years 2007-2016 were included. Primary ocular toxoplasmosis and reactivations were compared. RESULTS: Included were 22 patients, 64% female with a mean age of 29 ± 18 years, 59% (n = 13) were primary, 9% (n = 2) congenital and 32% (n = 7) reactivations. Visual acuity improved from 0.38 ± 0.44 to 0.20 ± 0.27 LogMAR (P = 0.026) after a mean of 37 ± 33 months. Initial lesion size was 2.38 ± 1.1 optic disc areas, reducing to 1.56 ± 1.24 following 2 months (34% reduction, P = 0.028) and to 1.17 ± 0.87 disc areas following one year (51% reduction, P = 0.012). Patients with macula-threatening lesions had worse visual acuity (0.50 ± 0.46 vs. 0.05 ± 0.07 LogMAR, P = 0.047). Primary and reactivation subgroups had similar presentations, visual outcomes and recurrence rates (all P > 0.05). CONCLUSIONS: In this population, primary ocular toxoplasmosis was the most common presentation. Lesion size reduced during the initial months with limited change thereafter and a third of cases recurred. Macula-threatening lesions were associated with worse visual acuity, and no significant differences were seen between the primary and reactivation subgroups.

Case report: a case of diffuse unilateral subacute neuroretinitis (DUSN) in a child.

BACKGROUND: Diffuse unilateral subacute neuroretinitis (DUSN) is a rare cause of posterior uveitis in the United Kingdom. It typically presents unilaterally in children and young adults but rarely bilateral cases have been reported. It is also rare to have multiple worms in the same eye causing the clinical picture. In this article, we present a challenging case of DUSN in a young girl unresponsive to conventional treatments suggesting the possibility of multiple worms being present in the same eye. CASE PRESENTATION: An 8-year-old girl presented with a 2-month history of headaches. On occasions the headaches were associated with redness and watering of her left eye. She denied any visual loss or visual symptoms. Her visual acuity was reduced to 6/30 in her left eye. Fundal examination revealed a unilateral chorioretinitis. Investigation did not reveal a specific cause for the chorioretinitis. Over 15 months her visual acuity improved to 6/9 but the fundal appearance changed and a diagnosis of DUSN was made. She was treated with focal laser, systemic anti-helminthic and immunosuppressive treatments but continued to develop new, active areas of chorioretinitis, raising the possibility of multiple worms in the sub-retinal space. There is also a concern as to other central nervous system (CNS) involvement given her significant and ongoing headaches. CONCLUSION: We present a challenging case of DUSN in a young girl; a condition that remains rare in the UK. She was unresponsive to both focal laser and systemic anti-helminthic and immunosuppressive treatments suggesting the possibility of multiple worms being present in the sub-retinal space. This case highlights the difficulties often encountered in the treatment of DUSN, even when a worm can be identified. Her visual prognosis is poor as there was ongoing recurrence of active chorioretinitis.

Assessment of ocular toxoplasmosis patients reported at a tertiary center in the northeast of Iran.

PURPOSE: Ocular toxoplasmosis, which is caused by the single-cell parasite Toxoplasma gondii, is currently the most significant cause of posterior uveitis in the world. No previous studies have described the prevalence and clinical features of ocular toxoplasmosis in the northeast of Iran. The purpose of the current study was to address this gap. METHODS: In this retrospective study, the medical records of 488 uveitis patients who presented to the Khatam-al-Anbia Eye Hospital of Mashhad University of Medical Sciences, a tertiary ophthalmology center in the northeast of Iran, between January 2013 and December 2015 were evaluated. The clinical features and risk factors of 99 (20%) consecutive patients with ocular toxoplasmosis were extracted. RESULTS: Ninety-nine including 53 (53.5%) female and 46 (46.5%) male patients with ocular toxoplasmosis were included in the analysis. Reduced vision (77%) and floaters (15.2%) were the most common presenting symptoms. The age category that was most affected by ocular toxoplasmosis was 20-40 years (range: 11-65 years) with a mean age of 27.2. All patients had retinochoroiditis, but just two had anterior uveitis. All of the extracted patients, with the exception of three patients, had unilateral involvement. None of the patients had any other medical disorders with the exception of one woman, who had diabetes. Only four recurring ocular toxoplasmosis patients were referred to the education hospital during the study. Serology data were available for just 32 patients, of which 31 (96.8%) were IgG positive, and 1 (3.2%) was IgM positive. CONCLUSION: Toxoplasma gondii was responsible for 20% of the patients of uveitis that presented to the largest ophthalmology center in the northeast of Iran. There is a high incidence of patients of ocular toxoplasmosis in the northeast of Iran, and it is a significant cause of uveitis and visual impairment in this area.

Activation of toxoplasma retinochoroiditis during pregnancy and evaluation of ocular findings in newborns.

The purpose of this study was to evaluate patients with activation of toxoplasma retinochoroiditis during pregnancy and ocular findings in newborns. A total of 17 pregnant patients who were clinically and serologically diagnosed with ocular toxoplasmosis were retrospectively reviewed. After birth, ocular findings for all infants were recorded. The mean age of the patients was 29.08 ± 5.71 years. In all cases, activation was present in only one eye. In 13 cases, anterior uveitis was associated with posterior uveitis. Visual acuity in all cases prior to treatment was 0.3 ± 0.21 and increased to 0.55 ± 0.29 after treatment. The mean gestational age of the patients was 19.76 ± 8.71 weeks at the time of hospital admission. No case of toxoplasmic ocular involvement was identified in the infants on postnatal examination. In the case of toxoplasma retinochoroiditis during pregnancy, appropriate treatment and follow-up is very important to protect the newborns and to prevent impaired vision in mothers.

Cytokine Signatures Associated With Early Onset, Active Lesions and Late Cicatricial Events of Retinochoroidal Commitment in Infants With Congenital Toxoplasmosis.

BACKGROUND: Ocular toxoplasmosis is a prominent and severe condition of high incidence in Brazil. The current study provides new insights into the immunological events that can be associated with retinochoroiditis in the setting of congenital toxoplasmosis in human infants. METHODS: Flow cytometry of intracytoplasmic cytokines in leukocyte subsets following in vitro short-term antigenic recall in infants with congenital T. gondii infection. RESULTS: Our data demonstrates that whereas neutrophils and monocytes from T. gondii-infected infants display a combination of proinflammatory and regulatory cytokine profiles, natural killer cells showed a predominantly proinflammatory profile upon in vitro T. gondii stimulation. The proinflammatory response of CD4(+) and CD8(+) T cells, characterized by the production of interferon γ (IFN-γ) and interleukin 17 in patients with an active retinochoroidal lesion, revealed the presence of IFN-γ and tumor necrosis factor α during early and late immunological events. This specific proinflammatory pattern is associated with early events and active retinochoroidal lesion, whereas a robust monocyte-derived interleukin 10-mediated profile is observed in children with cicatricial ocular lesions. CONCLUSIONS: These findings support the existence of a progressive immunological environment concomitant with the initial, apical, and cicatricial phases in the process of retinochoroidal lesion formation in infants with congenital toxoplasmosis that may be relevant in the establishment of stage-specific clinical management.

Post-prophylaxis Toxoplasma chorioretinitis following donor-recipient mismatched liver transplantation.

Toxoplasmosis may be transferred by organ transplantation. The most common clinical presentation is with multisystem disease, although isolated ocular toxoplasmosis has been described. Many centers have suggested that universal use of co-trimoxazole prophylaxis obviates the need for specific Toxoplasma testing. We report a case of donor-acquired ocular toxoplasmosis after liver transplantation despite co-trimoxazole prophylaxis. The diagnosis was confirmed by Toxoplasma polymerase chain reaction assay in conjunction with seroconversion. The fact that the infection was donor acquired was confirmed by serological mismatch and the absence of sporozoite-specific antigen antibody in the recipient.

Antibiotics versus no treatment for toxoplasma retinochoroiditis.

BACKGROUND: Acute toxoplasma retinochoroiditis causes transient symptoms of ocular discomfort and may lead to permanent visual loss. Antibiotic treatment aims primarily to reduce the risk of permanent visual loss, recurrent retinochoroiditis, and the severity and duration of acute symptoms. There is uncertainty about the effectiveness of antibiotic treatment. OBJECTIVES: To compare the effects of antibiotic treatment versus placebo or no treatment for toxoplasma retinochoroiditis. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision group Trials Register) (2016, Issue 1), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to February 2016), EMBASE (January 1980 to February 2016), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to February 2016), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov), and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 22 February 2016. We searched the reference lists of identified articles and contacted pharmaceutical companies for unpublished trials. SELECTION CRITERIA: We included randomised controlled trials that compared any antibiotic treatment against placebo or no treatment. We excluded trials that included immunocompromised participants. We considered any antibiotic treatment known to be active against Toxoplasma gondii. Antibiotic treatment could be given in any dose orally, by intramuscular injection, by intravenous infusion, or by intravitreal injection. DATA COLLECTION AND ANALYSIS: The primary outcomes for this review were visual acuity at least three months after treatment and risk of recurrent retinochoroiditis. Secondary outcomes were improvement in symptoms and signs of intraocular inflammation, size of lesion, and adverse events. We used standard methodological procedures expected by Cochrane. MAIN RESULTS: Four trials that randomised a total of 268 participants met the inclusion criteria. In all four studies antibiotic was administered orally.One study conducted in Brazil in both adults and children compared trimethoprim-sulfamexacocol over 20 months to no treatment and was judged to be at high risk of performance, detection, and attrition bias. The other three studies compared antibiotic treatment to placebo. We judged these three studies to be at a mixture of low or unclear risk of bias due to poor reporting. One study conducted in the US in adults studied pyrimethamine-trisulfapyrimidine for eight weeks; one study conducted in the UK in children and adults evaluated pyrimethamine for four weeks; and one study conducted in Brazil in adults investigated trimethoprim-sulfamethoxazole for 12 months. In the last study, all participants had active retinochoroiditis and were treated with antibiotics for 45 days prior to randomisation to trimethoprim-sulfamethoxazole versus placebo.Only the study in Brazil of trimethoprim-sulfamethoxazole over 12 months, in participants with healed lesions, reported the effect of treatment on visual acuity. People treated with antibiotics may have a similar change in visual acuity compared with people treated with placebo at one year (mean difference -1.00 letters, 95% confidence interval (CI) -7.93 to 5.93 letters; 93 participants; low-quality evidence).Treatment with antibiotics probably reduces the risk of recurrent retinochoroiditis compared with placebo (risk ratio (RR) 0.26, 95% CI 0.11 to 0.63; 227 participants; 3 studies; I(2) = 0%; moderate-quality evidence); similar results were seen for acute and chronic retinochoroiditis.The UK study of pyrimethamine for four weeks reported an improvement in intraocular inflammation in treated compared with control participants (RR 1.76, 95% CI 0.98 to 3.19; 29 participants; low-quality evidence). The study in Brazil of trimethoprim-sulfamethoxazole for 12 months stated that the severity of inflammation was higher in the comparator group when compared to the antibiotic-treated group but did not provide further details. In the US study of pyrimethamine-trisulfapyrimidine for eight weeks intraocular inflammation had almost completely resolved by eight weeks in all participants, however in this study all participants received steroid treatment.Two studies (UK and US studies) reported an increased risk of adverse events in treated participants. These were a fall in haemoglobin, leucocyte, and platelet count, nausea, loss of appetite, rash, and arthralgia. AUTHORS' CONCLUSIONS: Treatment with antibiotics probably reduces the risk of recurrent toxoplasma retinochoroiditis, but there is currently no good evidence that this leads to better visual outcomes. However, absence of evidence of effect is not the same as evidence of no effect. Further trials of people with acute and chronic toxoplasma retinochoroiditis affecting any part of the retina are required to determine the effects of antibiotic treatment on visual outcomes.

OUTCOMES AFTER PARS PLANA VITRECTOMY FOR EPIRETINAL MEMBRANES ASSOCIATED WITH TOXOPLASMOSIS.

PURPOSE: To evaluate outcomes and complications of pars plana vitrectomy in patients with epiretinal membrane secondary to toxoplasmic retinochoroiditis. METHODS: Retrospective evaluation of the records of 14 patients who underwent pars plana vitrectomy for epiretinal membrane secondary to toxoplasmic retinochoroiditis. The best-corrected visual acuity, intraoperative and postoperative complications, and macular optical coherence tomography were analysed. All patients received postoperative prophylactic treatment with trimethoprim/sulfamethoxazole. RESULTS: Fourteen patients, 5 men and 9 women, were included. Mean follow-up period after surgery was 6.07 ± 2.64 months. Preoperative mean best-corrected visual acuity was 20/200, and postoperative mean best-corrected visual acuity was 20/60. There were no intraoperative complications. Three patients developed posterior capsule opacification, and one patient developed cataract. CONCLUSION: Pars plana vitrectomy is a safe and effective procedure in patients with epiretinal membrane secondary to toxoplasmic retinochoroiditis, improving both visual acuity and anatomical result on macular optical coherence tomography. The most frequent postoperative complications were posterior capsule opacification and cataract. No recurrences of the disease were recorded.

Toxoplasma gondii isolates from chickens in an area with human toxoplasmic retinochoroiditis.

The aim of this study was to detect, isolate and genetically characterize Toxoplasma gondii from tissues obtained from free range chickens which were breed in farms from patients with toxoplasmic retinochoroiditis in Misiones, Argentina. Thirty three samples of head (refrigerated = 18 and frozen = 15) from free range chickens were processed. Refrigerated (n = 18) chicken central nervous systems (CNS) were bioassay in mice. DNA was obtained from all samples (n = 33) and PCR was performed using TOX5-TOX8 T. gondii specific primers. Positive PCR samples were characterized by nested-PCR and restriction fragment length polymorphism using the markers SAG2, BTUB, GRA6, SAG3, PK1, L358, C22-8, C29-2 and Apico. T. gondii DNA was amplified in 30.3% (10/33) of CNS samples. Isolates were obtained in 27.7% (5/18) of inoculated CNS samples (TgCk11-9Arg, TgCk13-5Arg, TgCk14-5Arg, TgCk14-6Arg and TgCk14-7Arg). Seven samples showed a restriction pattern to all markers and were identified as atypical with several alleles type III. Genotyping of T. gondii from samples of patients with retinochoroiditis in the same area could improve the understanding of the epidemiology of toxoplasmosis in the region.

Focal chorioretinitis in Thailand.

PURPOSE: To report the clinical features of patients with focal chorioretinitis (FCR), as well as toxoplasma serology. METHODS: We included 25 (4%) consecutive patients with FCR of 593 with uveitis. Controls consisted of 127 patients with posterior and panuveitis and clinical features other than FCR. Results of enzyme-linked immunosorbent assay for anti-Toxoplasma gondii immunoglobulin G (IgG) and IgM, demographic data, and clinical features of patients were registered. RESULTS: Positive anti-T. gondii IgG levels were observed in 21 of 25 patients (84%) with FCR in contrast to 14 of 127 patients (11%) with non-FCR (P < 0.001, Fisher test). The IgG levels >600 IU were found in 19 of 25 patients (76%) with FCR and in none of the patients with non-FCR (P < 0.001). All cases had unilateral involvement. Ocular features consisting of FCR and vitritis were present in all patients, but associated chorioretinal atrophic scars were not commonly seen (7/25 eyes; 28%). Retinal vasculitis was found in 9 of 25 eyes (36%) and affected solely the arteries. CONCLUSION: The majority of patients with FCR in Thailand exhibit highly positive anti-T. gondii IgG levels suggesting the presence of active systemic infection, which is also consistent with the absence of old scars. The absence of old scars and retinal arteritis were the features distinct from typical ocular toxoplasmosis lesions reported in the European and the U.S. series.

Macular hole secondary to toxoplasmic retinochoroiditis.

Ocular toxoplasmosis causes abnormalities in the vitreous that are responsible for several types of well-known complications including retinal detachment and epiretinal membranes. We report on a patient who developed toxoplasmic panuveitis with a full-thickness macular hole (MH) and was successfully treated with vitreoretinal surgery. A 35-year-old Hispanic female presented with a 2-week history of loss of visual acuity and metamorphopsia in her right eye. Funduscopy revealed a typical toxoplasmosis lesion and a MH, which was confirmed by optical coherence tomography. After 8 weeks of medical treatment with sulfamethoxazole (800 mg)/trimethoprim (160 mg) and steroids, the intraocular inflammation was considered inactive. Pars plana vitrectomy with inner limiting membrane peeling and injection of 24 % sulphur hexafluoride gas were performed to treat the MH, without success. Repeat pars plana vitrectomy was then performed with injection of 14 % perfluoropropane (C3F8). Closure of the MH was achieved after this second procedure. Vitreoretinal surgery may be safe and effective for treating MHs secondary to toxoplasmosis lesions, a very uncommon complication of this disease.

Atypical acquired toxoplasmosis.

A 33-year-old male presented with unilateral painless vision loss with a history of sub-tenon steroid for the same. The fundus showed an elevated focus of retinochoroiditis with vitritis. On investigating for the cause, polymerase chain reaction test on the anterior chamber tap was found to be positive for Toxoplasma. Such confusing and atypical cases usually produce a clinical dilemma and should be managed in a stepwise manner. Ancillary investigations usually provide a clue to the clinician and should be performed without any hesitation.

Macular Punctate Lesions Presenting as a Primary Manifestation of Ocular Toxoplasmosis.

PURPOSE: To study clinical features and outcomes of primary ocular Toxoplasmosis (OT) cases presenting as macular punctate lesions. METHODS: Retrospective review of three cases of OT with positive Toxoplasma serology. RESULTS: We describe three cases presenting as primary OT with no evidence of old retinochoroidal scar in either eye. All the cases had multiple foveal or extrafoveal, punctate, inner/outer, or combined lesions at macula with minimal vitreous reaction. During the first/primary episode, all the lesions resolved with 1. retinal atrophy, thinning (n = 1) or 2. Progressed to limited full-thickness retinitis lesions (n = 2). Recurrence as typical retinochoroiditis was seen in one eye. More than four-fold IgG positivity was seen in all cases while IgM positivity was seen in two cases. CONCLUSIONS: Macular punctate lesions (inner/outer/combination) can be the primary manifestation of ocular toxoplasmosis in the absence of old retinochoroiditis scars in either eye.

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

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

Role of IgG avidity in eyes with active Toxoplasma retinochoroiditis.

PURPOSE: To study the role of Toxoplasma IgG avidity in evaluating the stage of systemic infection during manifestation as toxoplasma retinochoroiditis and its clinical implications in eastern India. METHODS: Retrospective chart review of Toxoplasma retinochoroiditis cases with Toxoplasma serology for IgG, IgM, and IgG avidity. RESULTS: Included in this study were 17 eyes of 17 patients who had active retinitis located in the macula (14), mid-periphery (2), or periphery (1). They were either primary lesions (12) or reactivations (5). All the cases had Toxoplasma IgG positive; one case had IgM positivity, while all the cases had high IgG avidity values. IgG avidity had a positive correlation with the duration of symptoms. CONCLUSION: We observed high IgG avidity values in active retinochoroiditis in both primary ocular Toxoplasmosis and reactivation subgroups. These results indicate a late ocular manifestation after initial systemic infection with a possible incubation period ranging from 5 weeks to 5 months.

Clinical pattern of toxoplasmic retinochoroiditis in a Spanish referral center.

BACKGROUND/AIMS: To analyze the clinical pattern of ocular toxoplasmosis in a referral center in Spain. METHODS: The medical records of consecutive patients with ocular toxoplasmosis admitted from a single referral center for uveitis in Barcelona (Spain) were retrospectively analyzed between January 2005 and January 2011. RESULTS: One hundred and thirteen eyes from 113 patients (74 Spanish and 39 South American) with active ocular toxoplasmosis were analyzed with a 12-month follow-up. Final BCVA ≤ 20/200 was found in 30 eyes (26.5%). The most frequent complications were macular edema (16.8%) and epiretinal membrane (11.5%). Anterior chamber cell scores of ≥ 2+ (p = 0.003), vitreous cell scores of ≥ 2+ (p = 0.001), and the presence of cataracts (p = 0.047) or serous retinal detachment (p = 0.008) were more common among the South American than Spanish cohort. Active macular lesions (p < 0.001) with an initial BCVA ≤ 20/200 (p < 0.001) and advanced age (p = 0.019) were predictors for final BCVA ≤ 20/200, whereas female gender (p = 0.021) and an initial BCVA ≤20/200 (p = 0.045) were predictors for ocular complications. Moreover, a BCVA ≤ 20/200 (p < 0.001) and a vitreous cell score of ≥ 2+ (p = 0.045) at the initial examination were predictors of an eventual need for ocular surgery. CONCLUSION: The clinical features of ocular toxoplasmosis in Spanish patients differ from those of South American patients. In general, active macular lesions with an initial BCVA ≤ 20/200 and advanced age were shown to be predictors for final BCVA ≤ 20/200 in our patient cohort.

Ocular toxoplasmosis I: parasitology, epidemiology and public health.

Ocular toxoplasmosis results from retinal infection with the protozoan, Toxoplasma gondii. This parasite, which exists as multiple clonal subpopulations and in three stages, is capable of replication in any nucleated cell of its primary feline or multiple paratenic hosts. Human seroprevalence of toxoplasmosis is high across the globe, but with geographic variation. While prevalence of ocular toxoplasmosis is not well documented, toxoplasmic retinochoroiditis is the commonest form of posterior uveitis in many countries. Correlation of parasite genotype with disease is an important area of new research. Ocular infection with T. gondii often follows ingestion of bradyzoites in undercooked infected meat. Oocysts may survive for an extended period in the environment, and water contaminated with oocysts is an important source in toxoplasmosis epidemics. Ocular toxoplasmosis is preventable by a combination of community activities and personal measures. Public health action is well justified by the considerable burden of congenital and postnatal infections.

Intravitreal clindamycin plus dexamethasone versus classic oral therapy in toxoplasmic retinochoroiditis: a prospective randomized clinical trial.

Both oral and intraocular routes have been recommended for medication administration in toxoplasmic retinochoroiditis; however, available data, in support or against, are scarce. The objective of this study was to compare the efficacy of intravitreal clindamycin plus dexamethasone (IVCD) and conventional oral therapy (COT) including pyrimethamine, sulfadiazine, folinic acid and prednisone in active toxoplasmic retinochoroiditis. In this prospective randomized single-blind clinical trial, patients with active toxoplasmic retinochoroiditis received either IVCD (n = 32), or COT (n = 34) for 6 weeks. Changes of best-corrected visual acuity, retinal lesion size, and vitreous inflammation before and after treatment, as well as complications/side-effects and recurrence rate within at least 2 years of follow-up were compared between groups. Although all the variables improved significantly at 6 weeks within each group, changes were comparable between the IVCD and COT receivers. There was only one case with hepatotoxicity in the COT group which responded favorably to drug change. No injection-related complication was observed. Recurrence rates were 12.5 and 14.7 % in the IVCD and COT groups, respectively (p = 0.54). In conclusion, both IVCD and COT are equally effective against active toxoplasmic retinochoroiditis but the former is apparently safer and more convenient.