Primary Toxoplasmosis Research Articles

The prevention of congenital toxoplasmosis using a combination of Spiramycin and Cotrimoxazole: The long-time experience of a tertiary referral centre.

Toxoplasmosis is a parasitic infection caused by Toxoplasma gondii and is responsible for gestational and congenital infections worldwide. The current standard therapy is based on the administration of Spiramycin to prevent trans-placental transmission. Other therapies are being studied to reduce the rates of foetal transmission and symptomatic congenital infection. We report our long-standing experience in maternal toxoplasmosis infection treatment using a combination of Spiramycin-Cotrimoxazole, assessing its effectiveness in preventing vertical transmission compared to the expected incidence of congenital infection. We retrospectively collected cases of pregnant women referred to our centre for suspected toxoplasmosis infection according to Lebech criteria, treated with Spiramycin-Cotrimoxazole. Of 1364 women referred to our centre, postnatal follow-up of primary toxoplasmosis was available in 562 cases (73.9%). The overall vertical transmission rate was 3.4% in women treated immediately with Spiramycin-Cotrimoxazole after the diagnosis of infection. In comparison, it was 7.7% in women undergoing the same therapy but late or with poor compliance. The foetal transmission rate was 71.4% in untreated cases. All the infected newborns of mother treated adequately with Spiramycin-Cotrimoxazole were asymptomatic afterbirth, while 6/21 infected infants of the inadequate Spiramycin-Cotrimoxazole therapy group had postnatal sequelae (28.5%). The incidence of transmission after appropriate Spiramycin-Cotrimoxazole therapy was significantly lower than the expected rate reported in literature. A combination of Spiramycin and Cotrimoxazole is safe and effective in preventing foetal congenital toxoplasmosis and reducing sequelae in case of in-utero infection. The timing and adherence to the therapy are crucial to lowering the risk of congenital infection and neonatal morbidity.

Macular Punctate Lesions Presenting as a Primary Manifestation of Ocular Toxoplasmosis

ABSTRACT 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.

Role of IgG avidity in eyes with active Toxoplasma retinochoroiditis.

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. Retrospective chart review of Toxoplasma retinochoroiditis cases with Toxoplasma serology for IgG, IgM, and IgG avidity. 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. 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.

Comparison of the prevalence of risk factors for Toxoplasma Gondii infection among pregnant women in rural and urban areas in Poland.

Toxoplasma gondii is a protozoan parasite. While this infection typically exhibits no symptoms in humans, it poses a potential threat to the developing fetus in pregnant women. Several risk factors contribute to toxoplasmosis infection. Adherence to hygiene protocols and avoiding the consumption of raw meat, unwashed vegetables, and fruits may mitigate the risk of this disease. This study aimed to compare the prevalence of toxoplasmosis risk factors among pregnant women suspected of toxoplasmosis living in rural areas with those residing in urban areas. A retrospective observational study was conducted by analyzing data from the medical records of pregnant women suspected of toxoplasmosis. These women were consulted at the Provincial Infectious Diseases Hospital between September 2019 and March 2020. The analysis encompassed patients' demographic data and information concerning toxoplasmosis risk factors. A total of 273 women's data were included in the analysis. Diagnosis relied on serological verification using the VIDAS® analyzer (bioMérieux, Lyon, France). Women residing in rural areas were less likely to report a good socio-economic status (p=0.0064), and toxoplasmosis infection was less frequently ruled out (p=0.0023). In comparison to women living in urban areas, pregnant women from rural regions were more likely to have confirmed primary toxoplasmosis (p=0.0164). Additionally, they were more prone to working in gardens without gloves (p<0.0001), consuming unwashed vegetables (p=0.0025), eating raw meat during pregnancy (p=0.0008), and cats caregiving during pregnancy (p=0.0002). This exposure included both care for domestic cats before and during pregnancy (p=0.0069) and interactions with wild cats (p<0.0001). Pregnant women living in rural areas exhibited significantly higher exposure to toxoplasmosis risk factors. They also displayed a higher incidence of primary infections during pregnancy and a lower rate of excluded infections.

Primary Toxoplasmosis Acquired During Early Pregnancy: Is it Currently Overestimated?

(Abstracted from Eur J Obstet Gynecol Reprod Biol 2021;267:285–289) One of the more severe infectious complications for fetuses is primary toxoplasmosis acquired during pregnancy, especially when this occurs during the first trimester, as this infection can have devastating neurological consequences. The generally asymptomatic nature of this infection in healthy pregnant women requires serological screening or testing.

Primary toxoplasmosis acquired during early pregnancy: Is it currently overestimated?

ObjectiveToxoplasmosis acquired in early pregnancy is a potentially severe complication for the fetus. Evaluating the risk of transplacental infection in pregnant women accessing the Tuscany Reference Center for Infectious Diseases in Pregnancy during the last 20 years with suspected or confirmed toxoplasmosis acquired in early pregnancy was the aim of the study. Study designWe retrospectively enrolled all pregnant women undergoing amniocentesis for toxoplasmosis acquired in the first 16 gestational weeks in the period 1999–2019, comparing patients with certain acute infection (seroconversion occurred in pregnancy, CAIP) with those with suspected acute infection (IgG positive with low/intermediate IgG avidity index, SAIP). Results237 patients were enrolled, 187 (78.9%) with SAIP and 50 (21.1%) with CAIP. Specific IgM was detected in 47.5% and 76.7% (p-value 0.001), and the mean IgG avidity index was 22.7% and 7.1% (p-value < 0.001) in the SAIP and in the CAIP group, respectively. The mean delay from diagnosis to antibiotic initiation was 14.6 in SAIP and 11 days in CAIP group. Toxoplasma DNA was detected in the amniotic fluid in one case in a patient with CAIP. Excluding 24 newborns with not available data, prevalence of congenital infection was 0.47% [1/213 (95% CI 0.08%–2.61%)], 0% [0/178 (95% CI 0%–2.11%)] in SAIP and 2.8% [1/35 (95% CI 0.51%–14.53%)] in CAIP group. ConclusionsToxoplasmosis acquired in early pregnancy has a low risk of fetal infection. Actively discussing case-by-case amniocentesis indication with patients, especially when a recent toxoplasmosis is not properly confirmed, is desirable.

Toxoplasmosis, a rare case report that led to a successful pregnancy

A 19-year-old female patient was presented to our clinic for a pregnancy follow-up during which primary toxoplasmosis infection was diagnosed. The patient was successfully treated with spiramycin and finally delivered normally a healthy boy, on term. Serological tests (ELISA) for detection of anti-toxoplasma antibodies along with ultrasonography findings on the fetus are the gold standard for the diagnosis. Spiramycin was used for embryo protection to avoid T.gondii transmission to the fetus across the placenta.

Ocular Toxoplasmosis after Exposure to Wild Game

ABSTRACT 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.

Decreasing trend in Toxoplasma seroprevalence among pregnant women in Kuwait.

Primary toxoplasmosis early in pregnancy may cause fetal pathology. Understanding and documenting serological epidemiology and associated risk factors about Toxoplasma gondii infection is crucial to offering appropriate interventions to prevent such fetal pathology. To determine the seroepidemiological status and major risk factors associated with T. gondii infection among pregnant women in Kuwait. This was an observational cross-sectional multicentre descriptive study. Blood samples and sociodemographic information were collected from 280 pregnant women attending antenatal clinics. The blood samples were screened with VIDAS Toxo-IgG/IgM and SERIONE IgG/IgM and IgG avidity assays to detect T. gondii-specific antibodies. Overall seroprevalence of T. gondii IgG and IgM antibodies among pregnant women was 12.5% and 2.1%, respectively. Only two IgG-positive women had low IgG avidity suggesting acute infection. No significant association was observed between seroprevalence and known risk factors for toxoplasmosis. This is believed to be the first study of T. gondii infection and its associated risk factors among pregnant women in Kuwait. The seroprevalence rate of 12.5% is one of the lowest in the Middle East. There was no significant association between T. gondii seroprevalence and known risk factors. This may have been due to the high education level (>94%) among pregnant women that may have changed women's behavior during pregnany, thus minimizing transmission of toxoplasmosis.

An immunocompetent young man with diffuse pulmonary infiltrates.

Pneumonitis due to primary toxoplasmosis in an immunocompetent subject is rare. Here, the mononucleosis-like syndrome, associated with serological evidence of T. gondii infection and positive PCR for T. gondii in BAL, allowed us to establish the diagnosis. https://bit.ly/3qHE2U7

Role of Toxoplasma gondii IgG Avidity Testing in Discriminating between Acute and Chronic Toxoplasmosis in Pregnancy

Risk of mother-to-child transmission of Toxoplasma gondii during pregnancy is much greater in women who are exposed to primary T. gondii infection (toxoplasmosis) after conception compared to those who were exposed to the infection before conception. Therefore, laboratory tests that help classify recent primary toxoplasmosis are important tools for the management of pregnant women suspected to have T. gondii exposure. Detection of Toxoplasma IgM (Toxo IgM) is a sensitive indicator of primary toxoplasmosis, but the indicator specificity is low because sometimes natural IgM antibodies react with Toxoplasma antigens in the absence of the infection. Furthermore, Toxo IgM sometimes persists in blood serum for several months or years following the primary infection. In recent decades, Toxo IgG avidity assay has been used as a standard diagnostic technique for a better estimation of the infection acquisition time and identification of the primary T. gondii infection during pregnancy. Avidity is described as the aggregate strength; by which, a mixture of polyclonal IgG molecules reacts with multiple epitopes of the proteins. This parameter matures gradually within 6 months of the primary infection. A high Toxo IgG avidity index allows a recent infection (less than 4 months) to be excluded, whereas a low Toxo IgG avidity index indicates a probable recent infection with no exclusions of the older infections. This minireview is based on various aspects of T. gondii IgG avidity testing, including (i) description of avidity and basic methods used in primary studies on T. gondii IgG avidity and primary infections; (ii) importance of IgG avidity testing in pregnancy; (iii) result summary of the major studies on the use of T. gondii IgG avidity assay in pregnancy; (iv) brief explanation of the T. gondii IgG avidity values in newborns; (v) result summary of the major studies on T. gondii IgG avidity and PCR; (vi) discussion of commercially available T. gondii IgG avidity assays, including newer automated assays; and (vii) current issues and controversies in diagnosis of primary T. gondii infections in pregnancy.

Unmasking of infectious retinitis and intraocular lymphoma in patients after uneventful dropless cataract surgery.

In this case series, 3 unique cases of severe immune-mediated pathologies (primary ocular lymphoma, toxoplasmosis chorioretinitis, and syphilitic retinitis) after dropless cataract surgery with intraocular steroid injection are reported. Patient immune status and subsequent local immunosuppression after dropless cataract surgery played roles in the worsening of these pathologies. This report demonstrates the need for vigilance when administering immunosuppressive agents locally during cataract surgery.

Primary toxoplasmosis complicated by possible IRIS 15 years after renal transplantation

Abstract Background Acute toxoplasmosis in the transplant recipient can be a serious infection and usually represents reactivation of latent infection. Primary toxoplasmosis after transplantation is much rarer and is associated with greater morbidity and mortality. We report a case of primary toxoplasmosis 15 years after kidney transplantation with concomitant Epstein–Barr virus (EBV) reactivation as well as an IRIS-like reaction to anti-toxoplasma treatment. Case report A 26-year-old man, who received a living donor kidney transplant 15 years previously, presented with a 1-week history of fevers, headache, photophobia and dry cough. Immunosuppression was maintained with prednisolone 5 mg daily, mycophenolate mofetil (MMF) 500 mg twice daily and tacrolimus 5 mg twice daily. He was treated empirically for meningitis, although initial investigations were unremarkable. Due to worsening of symptoms, he was transferred to the transplant centre where he was also investigated for suspected post-transplant lymphoproliferative disorder owing to rising titres of EBV DNA. Retrospective serology and PCR supported a diagnosis of primary toxoplasmosis and he started treatment with sulfadiazine and pyrimethamine. After 72 h, he presented with recrudescence of fever and worsening lymphadenopathy. Sulfadiazine was switched to clindamycin with good effect and his symptoms resolved. Unfortunately, his kidney transplant later failed and he re-commenced haemodialysis. Conclusions Primary toxoplasmosis after kidney transplantation is rare, with existing literature limited to case-series and case reports. Since 1966, there have been 20 well described cases. Early presentation post-transplant is associated with worse outcomes. Acute toxoplasmosis may have resulted in concomitant EBV reactivation due to impaired immunosurveillance and specific cell-mediated immunity. There is a lack of consensus regarding toxoplasma screening and chemoprophylaxis in transplant recipients. A high index of suspicion is required to ensure that cases are not missed and transplant recipients should receive counselling to prevent infection.

Rhombencephalitis secondary to toxoplasma gondii infection: Case report and literature review

Immunocompetent (IC) individuals with primary toxoplasmosis are usually asymptomatic. However, in some IC, toxoplasmosis can present with brainstem encephalitis. We report an adult female patient with headache associated with worsening coordination. Physical examination showed bilateral, symmetrical, and nontender cervical lymphadenopathy. Toxoplasmosis immunoglobulin G (IgG) and IgM were high, and the IgG antibody avidity pattern was low. The cerebrospinal fluid analysis was requested that revealed a positive polymerase chain reaction results for toxoplasmosis. A brain magnetic resonance imaging (MRI) showed a T1-hypointense left pontine lesion. Pyrimethamine and sulfadiazine were started. After 1 month, the patient had full recovery. Four months after, the individual was admitted due to progressive abnormal eye movements and tremor. Her neurological examinations showed ocular myoclonus and Holmes tremor. A second brain MRI showed hypertrophy of the ipsilateral inferior olivary nucleus. In the follow-up, her symptoms decreased mildly. The tremor was managed with clonazepam and levodopa. Furthermore, immune suppression investigation was negative.

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

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. 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. Included were 22 patients, 64% female with a mean age of 29 ± 18years, 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 ± 33months. Initial lesion size was 2.38 ± 1.1 optic disc areas, reducing to 1.56 ± 1.24 following 2months (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). 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.

Littermate cats rescued from a shelter succumbed to acute, primary toxoplasmosis associated with TOXO DB genotype #4, generally circulating in wildlife

Cats are important in the epidemiology of Toxoplasma gondii infection because they are the only hosts that can excrete the environmentally resistant oocysts in the environment. Although exposure is common (approximately 30% of cats in the USA), clinical toxoplasmosis is relatively rare. Here, we report overwhelming disseminated toxoplasmosis in two litter mate 8-week-old kittens, thought to have acquired toxoplasmosis postnatally. Five domestic shorthair kittens, approximately 2–3 weeks of age, and the queen were found in upstate New York by a rescue group in spring of 2018. The kittens and queen were placed in a foster home for approximately 4–5 weeks and then transferred to a shelter. Two kittens died unexpectedly following a short illness. Postmortem examination of the two deceased kittens revealed overwhelming toxoplasmosis and the presence of entero-epithelial stages in small intestine, suggestive of recent ingestion of infected tissues. Antibodies to T. gondii were found in the deceased kittens and the queen but not in the three asymptomatic littermate kittens. No obvious cause of immunosuppression was demonstrated. Genetic typing of T. gondii from DNA extracted from liver and lungs of both kittens revealed Toxo DB #4 genotype, commonly found in wildlife. Owners and veterinarians should be aware of dangers of feeding raw meat to cats and contact with infected cat feces. Procedures to safely handle T. gondii infected feces in hospital setting are outlined.

Primary Ocular Toxoplasmosis Presenting to Uveitis Services in a Non-endemic Setting.

PurposeThis study sought to describe the different clinical features and presentations of primary ocular toxoplasmosis in a setting not demonstrating an outbreak of disease.MethodsThis was a retrospective review of patients presenting to uveitis management services in Auckland and Hamilton, New Zealand between 2003 to 2018 with uveitis and positive toxoplasmosis immunoglobulin M serology.ResultsWe identified 16 patients with primary acquired toxoplasmosis infection and ocular involvement. The mean age was 53 years. Systemic symptoms were reported in 56% (9 / 16). Visual acuity was reduced to 20 / 30 or less in 50% of patients (8 / 16). A single focus of retinitis without a pigmented scar was the salient clinical feature in 69% (11 / 16). Optic nerve inflammation was the sole clinical finding in 19% (3 / 16). Bilateral arterial vasculitis was the sole clinical finding in 13% (2 / 16). A delay in the diagnosis of toxoplasmosis of more than two weeks occurred in 38% (6 / 16) due to an initial alternative diagnosis. Antibiotic therapy was prescribed in all cases. Vision was maintained or improved in 69% (11 / 16) at the most recent follow-up visit (15 months to 10 years). Relapse occurred in 69% (11 / 16), typically within four years from the initial presentation.ConclusionsPrimary ocular toxoplasmosis presenting in adulthood is a relatively uncommon cause of posterior uveitis in New Zealand. This condition should be considered in any patient presenting with retinitis or optic nerve inflammation without a retinochoroidal scar. This disease tends to relapse; thus, close follow-up is required.

Cellular immunopathogenesis in primary Toxoplasma gondii infection during pregnancy.

Congenital toxoplasmosis is caused by the vertical transmission of infection from mother to foetus through the placenta when a pregnant woman is infected with Toxoplasma gondii (T.gondii). Congenital infection can have serious consequences, such as intrauterine abortion, foetal death and severe neurological, ocular or other organ damage in the foetus. In this review, we focus on recent publications investigating vertical transmission of T.gondii infection, cellular immunopathogenesis and protective immunity in primary toxoplasmosis during pregnancy.

Toxoplasmosis in the non-orthotopic heart transplant recipient population, how common is it? Any indication for prophylaxis?

Unlike in orthotopic heart transplant (OHT) setting where toxoplasma prophylaxis is a standard practice in pretransplant toxoplasma seronegative recipients who have received donor hearts from seropositive donors (D+/R-), there is no consensus regarding prophylaxis in non-OHT recipients. The incidence of toxoplasma disease in non-OHT recipients is less than 1% but its true burden is underestimated. Among 31 cases of toxoplasma disease reported from 2004 through 2017, renal and liver transplant recipients comprised of 90% of cases. A total of 94% of 18 recipients with known pretransplant serology were seronegative recipients (mostly D+/R-). Out of 16 recipients with adequate information, 10 (63%) and five (31%) were deemed to be donor derived and nondonor-derived primary toxoplasmosis respectively. Tissue invasive reactivation was uncommon. Almost all cases were described in patients not on prophylaxis at the time of presentation. Universal screening of donor/recipient toxoplasma serology for risk stratification is beneficial as illustrated by reports of fatal cases of toxoplasmosis due to unavailability of positive donor serology results. Toxoplasma disease in non-OHT predominantly occurs in pretransplant seronegative recipients- mostly in D+/R- group and is rare in seropositive recipients. Posttransplant prophylaxis should be targeted against the high-risk D+/R- group and should be considered in seropositive recipients in whom unusually high immunosuppression is implemented. Toxoplasma serologies and PCR should be used in combination for the diagnosis of toxoplasmosis in non-OHT patients.

Isothermal PCR for Feasible Molecular Diagnosis of Primary Toxoplasmosis in Women Recently Experienced Spontaneous Abortion.

AIM:The current study aimed to assess the practicability of a simple loop-mediated isothermal amplification (LAMP) about real-time quantitative PCR to diagnose primary toxoplasmosis among high-risk pregnant women.METHODS:Cloned Toxoplasma samples were used to calculate the analytical sensitivity while specificity was assessed using pooled DNA samples extracted from other parasitic stages.RESULTS:Both techniques showed 100% sensitivity and specificity and then applied to detect recent Toxoplasma infection in peripheral blood of 77 IgG negative women out of a total 139 women lately experienced spontaneous abortion. The 2 techniques obtained positive results in 8 samples confirming primary toxoplasmosis.CONCLUSION:Generally, LAMP assay is a simple, cost-effective molecular technique can be completed in less than half an hour to diagnose primary Toxoplasma infection. The technique can be applied in a minimally equipped laboratory by ordinary workers to screen the vulnerable groups. Further analysis using larger samples with the quantitative approach is recommended to confirm the sensitivity of this emergent molecular technique.