Toxoplasma gondii, a plea for a thorough investigation of its oncogenic potential.

It is estimated that 30 % of the world's population harbours the parasite Toxoplasma gondii, particularly in the brain. Beyond its implication in potentially severe opportunistic or congenital infections, this persistence has long been considered as without consequence. However, certain data in animals and humans suggest that this carriage may be linked to various neuropsychiatric or neurodegenerative disorders. The hypothesis of a potential cerebral oncogenicity of the parasite is also emerging. In this personal view, we will present the epidemiological arguments in favour of an association between toxoplasmosis and cerebral malignancy, before considering the points that could underlie a potential causal link. More specifically, we will focus on the brain as the preferred location for T. gondii persistence and the propensity of this parasite to interfere with the apoptosis and cell cycle signalling pathways of their host cell.

Novel paradigm enables accurate monthly gestational screening to prevent congenital toxoplasmosis and more.

Background: Congenital toxoplasmosis is a treatable, preventable disease, but untreated causes death, prematurity, loss of sight, cognition and motor function, and substantial costs worldwide. Methods/Findings: In our ongoing USA feasibility/efficacy clinical trial, data collated with other ongoing and earlier published results proved high performance of an Immunochromatographic-test(ICT) that enables accurate, rapid diagnosis/treatment, establishing new paradigms for care. Overall results from patient blood and/or serum samples tested with ICT compared with gold-standard-predicate-test results found ICT performance for 4606 sera/1876 blood, 99.3%/97.5% sensitive and 98.9%/99.7% specific. However, in the clinical trial the FDA-cleared-predicate test initially caused practical, costly problems due to false-positive-IgM results. For 58 persons, 3/43 seronegative and 2/15 chronically infected persons had false positive IgM predicate tests. This caused substantial anxiety, concerns, and required costly, delayed confirmation in reference centers. Absence of false positive ICT results contributes to solutions: Lyon and Paris France and USA Reference laboratories frequently receive sera with erroneously positive local laboratory IgM results impeding patient care. Therefore, thirty-two such sera referred to Lyon's Reference laboratory were ICT-tested. We collated these with other earlier/ongoing results: 132 of 137 USA or French persons had false positive local laboratory IgM results identified correctly as negative by ICT. Five false positive ICT results in Tunisia and Marseille, France, emphasize need to confirm positive ICT results with Sabin-Feldman-Dye-test or western blot. Separate studies demonstrated high performance in detecting acute infections, meeting FDA, CLIA, WHO ASSURED, CEMark criteria and patient and physician satisfaction with monthly-gestational-ICT-screening. Conclusions/Significance: This novel paradigm using ICT identifies likely false positives or raises suspicion that a result is truly positive, rapidly needing prompt follow up and treatment. Thus, ICT enables well-accepted gestational screening programs that facilitate rapid treatment saving lives, sight, cognition and motor function. This reduces anxiety, delays, work, and cost at point-of-care and clinical laboratories. Author's Summary: Toxoplasmosis is a major health burden for developed and developing countries, causing damage to eyes and brain, loss of life and substantial societal costs. Prompt diagnosis in gestational screening programs enables treatment, thereby relieving suffering, and leading to > 14-fold cost savings for care. Herein, we demonstrate that using an ICT that meets WHO ASSURED-criteria identifying persons with/without antibody to Toxoplasma gondii in sera and whole blood with high sensitivity and specificity, is feasible to use in USA clinical practice. We find this new approach can help to obviate the problem of detection of false positive anti- T.gondii IgM results for those without IgG antibodies to T.gondii when this occurs in present, standard of care, predicate USA FDA cleared available assays. Thus, this accurate test facilitates gestational screening programs and a global initiative to diagnose and thereby prevent and treat T.gondii infection. This minimizes likelihood of false positives (IgG and/or IgM) while maintaining maximum sensitivity. When isolated IgM antibodies are detected, it is necessary to confirm and when indicated continue follow up testing in ∼2 weeks to establish seroconversion. Presence of a positive ICT makes it likely that IgM is truly positive and a negative ICT makes it likely that IgM will be a false positive without infection. These results create a new, enthusiastically-accepted, precise paradigm for rapid diagnosis and validation of results with a second-line test. This helps eliminate alarm and anxiety about false-positive results, while expediting needed treatment for true positive results and providing back up distinguishing false positive tests.

[Toxoplasmosis in pregnancy: Practical Management]. / Toxoplasmose pendant la grossesse : proposition actuelle de prise en charge pratique.

The burden of congenital toxoplasmosis has become small in France today, in particular as a result of timely therapy for pregnant women, fetuses and newborns. Thus, the French screening and prevention program has been evaluated and recently confirmed despite a decline over time in the incidence of toxoplasmosis. Serological diagnosis of maternal seroconversion is usually simple but can be difficult when the first trimester test shows the presence of IgM, requiring referral to an expert laboratory. Woman with confirmed seroconversion should be referred quickly to an expert center, which will decide with her on treatment and antenatal diagnosis. Although the level of proof is moderate, there is a body of evidence in favor of active prophylactic prenatal treatment started as early as possible (ideally within 3 weeks of seroconversion) to reduce the risk of maternal-fetal transmission, as well as symptoms in children. The recommended therapies to prevent maternal-fetal transmission are: (1) spiramycin in case of maternal infection before 14 gestational weeks; (2) pyrimethamine and sulfadiazine (P-S) with folinic acid in case of maternal infection at 14 WG or more. Amniocentesis is recommended to guide prenatal and neonatal care. If fetal infection is diagnosed by PCR on amniotic fluid, therapy with P-S should be initiated as early as possible or continued in order reduce the risk of damage to the brain or eyes. Further research is required to validate new approaches to preventing congenital toxoplasmosis.

Comparison of matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) systems for the identification of moulds in the routine microbiology laboratory.

OBJECTIVES: The purpose of this study was to compare the efficiency of mould identification of two matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) systems - Vitek MS (VMS) and Microflex LT (MLT) - and the MSI application. METHODS: Moulds were collected retrospectively and prospectively to display epidemiological diversity of a microbiology laboratory. All of them were identified via sequencing. Strains were then identified using the VMS v3.0, the MLT, and the MSI software applied on MLT spectra. Rates of correct identifications to the species, to the complex, and to the genus level were compared with the molecular reference standard. RESULTS: A total of 102 isolates were collected. The rate of correct identification to the species level with the MLT was 42.2% (43/102) with a threshold of 1.7 (vs. 16.7% (17/102) with a threshold of 2.0, p < 0.05). The VMS performed better than the MLT with a threshold of 1.7 for species (49.0% (50/102), p 0.33) and complex level identifications (71.6% (73/102) vs. 54.9% (56/102), p < 0.05). However the highest performances were observed when the MLT spectra were analysed via the Mass Spectrometry Identification (MSI) software reaching 90.2% (92/102) of correct identification to the species, 92.2% (94/102) to the species complex and 94.1% (96/102) to the genus level. CONCLUSIONS: The VMS performed better than the MLT for mould identification. However, it remains of utmost importance to expand commercial databases, as performances of the MLT highly improved when using the MSI software and its extended database, reaching far above the VMS system. Thus the VMS could benefit from the use of this online tool.

Prospective survey of azole drug resistance among environmental and clinical isolates of Aspergillus fumigatus in a French University hospital during major demolition works.

OBJECTIVES: Recent studies have reported the emerging worldwide problem of azole drug resistance of A. fumigatus isolates. The aim of this study was to evaluate the antifungal susceptibilities of A. fumigatus isolates recovered from air and clinical samples collected in a French University hospital (Lyon), which underwent major deconstruction works over a one year-period. METHODS: A daily surveillance of fungal contamination was implemented during 11-months. Environmental survey was realized by air samplings, outdoor and indoor, with an automatic agar sampler. In parallel, surveillance of IA infection cases was conducted by epidemiological investigation. Environmental and clinical isolates of A. fumigatus were identified by conventional methods and ß-tubulin sequencing. Susceptibility testing of A. fumigatus isolates against Itraconazole (ITZ), Voriconazole (VCZ) was performed using Etest method. RESULTS: A total of 3885 air samples (1744 outdoor samples and 2141 indoor samples) were collected. From the 3073 identified colonies of A. fumigatus, 400 A. fumigatus isolates were tested for their susceptibility to ITZ and VCZ, including 388 isolates coming from the environment (indoor n:157, outdoor n:231) and 12 isolates coming from clinical samples. All the 400 isolates were susceptible to azoles (≤1µg/mL). CONCLUSIONS: No environmental reservoir of A. fumigatus azole resistant strains was found in our hospital which was undergoing major demolition works. Further studies with larger number of A. fumigatus clinical isolates and environmental isolates from agricultural areas and healthcare establishments are needed to better appreciate the occurrence and prevalence of azole resistance.

Species of Metarhizium anisopliae complex implicated in human infections: retrospective sequencing study.

OBJECTIVES: Fungi belonging to the Metarhizium anisopliae complex comprise ubiquitous arthropod pathogenic moulds used as mycopesticides. Rare cases of human infections due to M. anisopliae have been reported. We hypothesize misidentifications of fungal strains implicated in these cases or used in mycopesticides. METHODS: A review of the literature was conducted to identify previously published cases. We collected some of these previous described strains and reported new cases, and a French mycopesticide containing M. anisopliae. All identifications were performed based on elongation factor-1α gene sequencing. RESULTS: We report eight new cases of Metarhizium infection in humans (three from France and five from Australia). The strains isolated from these cases, and three others from already published cases and reported as M. anisopliae, were molecularly identified based on elongation factor-1α (Ef1-α) gene sequencing as follows: Metarhizium robertsii (six), Metarhizium guizhouense (three), Metarhizium brunneum (one) and Metarhizium pingshaense (one). CONCLUSIONS: In this study, we report new human cases of Metarhizium infections, and, based on Ef-1α gene sequencing, we demonstrate the misidentification of species in case reports. We also correct the species identification of a strain reported as M. anisopliae used in a commercially available mycopesticide. According to our results, none of the strains from the human infection reports reviewed belongs to the species M. anisopliae.

Landscape and climatic characteristics associated with human alveolar echinococcosis in France, 1982 to 2007.

Human alveolar echinococcosis (AE) is a severe hepatic disease caused by Echinococcus multilocularis. In France, the definitive and intermediate hosts of E. multilocularis (foxes and rodents, respectively) have a broader geographical distribution than that of human AE. In this two-part study, we describe the link between AE incidence in France between 1982 and 2007 and climatic and landscape characteristics. National-level analysis demonstrated a dramatic increase in AE risk in areas with very cold winters and high annual rainfall levels. Notably, 52% (207/401) of cases resided in French communes (smallest French administrative level) with a mountain climate. The mountain climate communes displayed a 133-fold (95% CI: 95-191) increase in AE risk compared with communes in which the majority of the population resides. A case-control study performed in the most affected areas confirmed the link between AE risk and climatic factors. This arm of the study also revealed that populations residing in forest or pasture areas were at high risk of developing AE. We therefore hypothesised that snow-covered ground may facilitate predators to track their prey, thus increasing E. multilocularis biomass in foxes. Such climatic and landscape conditions could lead to an increased risk of developing AE among humans residing in nearby areas.

[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.

Congenital toxoplasma infection: monthly prenatal screening decreases transmission rate and improves clinical outcome at age 3 years.

BACKGROUND: Toxoplasma infection during pregnancy exposes the fetus to risks of congenital infection and sequelae that depend heavily on gestational age (GA) at time of infection. Accurate risk estimates by GA are necessary to counsel parents and improve clinical decisions. METHODS: We analyzed data from pregnant women diagnosed with acute Toxoplasma infection in Lyon (France) from 1987 to 2008 and assessed how the risks of congenital toxoplasmosis and of clinical signs at age 3 years vary depending on GA at the time of maternal infection. RESULTS: Among 2048 mother-infant pairs, 93.2% of mothers received prenatal treatment and 513 (24.7%) fetuses were infected. Because of a significant reduction in risk since 1992 when monthly screening was introduced (59.4% vs 46.6% at 26 GA weeks; P = .038), probabilities of infection were estimated on the basis of maternal infections diagnosed after mid-1992 (n = 1624). Probabilities of congenital infection were <10% for maternal infections before 12 weeks of gestation, rose to 20.0% at 19 weeks, and then continued increasing to 52.3% and almost 70% at 28 and 39 GA weeks, respectively. Because of a significant reduction in risk of clinical signs of congenital toxoplasmosis in infected children born from mothers diagnosed after 1995 when polymerase chain reaction testing on amniotic fluid was initiated (87/794 vs 46/1150; P = .012), probabilities of clinical signs at 3 years were estimated based on 1015 maternal infections diagnosed after 1995 including 207 infected children, with symptoms in 46 (22.2%). CONCLUSIONS: These analyses demonstrated that introduction of monthly prenatal screening and improvement in antenatal diagnosis were associated with a significant reduction in the rate of congenital infection and a better outcome at 3 years of age in infected children. Our updated estimates will improve individual management and counseling in areas where genotype II Toxoplasma is predominant.

Seasonal variations in acute toxoplasmosis in pregnant women in the Rhône-Alpes region (France).

To search for seasonal variations we analysed data on 1998 acute toxoplasmic infections diagnosed between 1988 and 2009 in pregnant women. Two distinctive transmission profiles were observed: one in rural areas, which was strongly influenced by seasons with significantly fewer infections in the first half of the year but maximal risks at the end of summer and end of autumn, and a stable urban distribution with only moderate peaks. Further studies on individual risks and environmental and climatic factors are needed to understand what prevention message should be given to susceptible pregnant women.

Congenital toxoplasmosis in France in 2007: first results from a national surveillance system.

When immunocompetent people become infected with the parasite Toxoplasma gondii, the disease is generally asymptomatic. However, transplacental transmission of T. gondii may lead to severe congenital infection including in utero abortion, foetal death, or neurological or ocular damage of the foetus. France has had a national programme to prevent congenital toxoplasmosis since 1978. However, although estimated seroprevalence in pregnant women has fallen from 84% in the 1960s to 44% in 2003, no reliable data have been available on the annual number of cases of congenital toxoplasmosis or the severity of infection. In 2006, the French National Institute for Public Health Surveillance (Institut de Veille Sanitaire) and the National Reference Centre for Toxoplasmosis recommended that a national laboratory-based surveillance system be used for the surveillance of the disease. In 2007, 31 laboratories reported at least one congenital case through the surveillance system, giving a total of 272 cases. A total of 11 terminations of pregnancy were reported (six abortions and five foetal deaths). Of the live-born cases, 206 were asymptomatic, 28 were symptomatic and seven had a severe form of the disease. As there were 818,700 births in France and French overseas departments in 2007, the overall prevalence of congenital toxoplasmosis observed that year was 3.3 (95% confidence interval (CI): 2.9 to 3.7) per 10,000 live births and the incidence rate of the disease at birth was 2.9 (95% CI: 2.5 to 3.2) per 10,000 live births; the estimated incidence rate of symptomatic congenital toxoplasmosis was 0.34 (95% CI: 0.2 to 0.5) cases per 10,000 live births.

Factors affecting the adherence to an antenatal screening programme: an experience with toxoplasmosis screening in France.

Monthly serological testing is mandatory in France for pregnant women not immune to toxoplasmosis. We assessed for the first time the adherence to this national programme, using data from antenatal tests for Toxoplasma antibodies collected by the Union of Health Insurance Services in the French Rhone-Alpes region.

Impact of spiramycin treatment and gestational age on maturation of Toxoplasma gondii immunoglobulin G avidity in pregnant women.

The objective of the present study was to investigate the maturation of immunoglobulin G (IgG) avidity after Toxoplasma gondii seroconversion during pregnancy and the factors that affect IgG avidity over time. The study used 309 serum samples from 117 women and a multiple linear mixed regression analysis to show the patterns of variation of IgG avidity throughout gestation. The IgG avidity ratios and the patterns of their evolution with time were quite diverse among the women and were statistically heterogeneous (P = 0.011); however, the trend was toward a statistically significant increase (P < 0.0001). On average, a 1.0167-fold increase was observed for each additional gestational week after the putative date of infection. At 12 weeks after putative infection (the expected IgG avidity maturation time), the mean avidity ratio was 16.6% (95% confidence interval, 15.4 to 17.9%). At all times, the avidity ratio remained significantly heterogeneous among the women (P < 0.05); for 95% of them, that ratio ranged from 7.8 to 35.3% at 12 weeks after putative infection. Maternal age at the putative time of infection did not influence the maturation of IgG avidity. However, on average, a 1.009-fold decrease (P = 0.03) in that avidity was observed for each additional week of gestational age before infection and a 1.03-fold increase (P = 0.0003) was observed for each additional week of delay to the onset of spiramycin treatment. The rate of increase in the avidity ratio was lower if infection occurred late in pregnancy and higher if the delay to treatment was long. This information cannot allow accurate determination of the delay since the time of infection. The present results provide support for interpretation of the assay and caution against overinterpretation.

Delayed maturation of immunoglobulin G avidity: implication for the diagnosis of toxoplasmosis in pregnant women.

The low avidity of immunoglobulin G has been reported to be a useful marker of recent infection with Toxoplasma. Several investigators, however, have published discrepant result on the maturation of avidity over time. The aim of this study was to analyse persistent low avidity of immunoglobulin G in immunocompetent individuals and in pregnant women and how it could interfere in the flowchart of antenatal diagnosis of toxoplasmosis in the latter group. An international literature search was conducted together with a retrospective study of a hospital database. Eleven publications that met the inclusion criteria reported delayed maturation of avidity at a frequency ranging from 0 to 66.6% of the patients. Examination of those publications demonstrated an important heterogeneity in the type of assay used, the calculation of avidity, the cutoff above which avidity was considered to be elevated, and the delay since infection after which indices are expected to be high. In the hospital database, persistent low avidity was found even after a median follow-up period of 6 years. Different factors could interfere with maturation of avidity, such as variations between individuals, the assay system used, and, possibly, the treatment administered. The results of this study clearly demonstrate that, in a pregnant woman, an acute infection cannot be reliably diagnosed solely on the basis of low avidity of immunoglobulin G. Further investigations and standardization of assays are urgently needed. Estimation of the time of infection remains difficult, especially in cases in which the samples are drawn late in pregnancy; the final estimate must be based on several tests repeated at intervals of weeks.

[Congenital ocular toxoplasmosis--ocular manifestations and prognosis after early diagnosis of infection]. / Kongenitale okuläre Toxoplasmose -- Okuläre Manifestationen und Verlauf nach Frühdiagnostik der Infektion.

BACKGROUND: Congenital toxoplasmosis (CT) is the most frequently encountered congenital infection. The aim of the present review is to report about the long-term outcome of functional and morphological manifestations after an early confirmation of the diagnosis. PATIENTS AND METHODS: We report on a cohort of patients with serologically confirmed CT, born between 1988 and 2001, who were followed up prospectively at a single centre (Institute of Parasitology, Hôpital de la Croix Rousse, University of Lyon). All patients underwent regular ophthalmological, parasitological and paediatric controls on a half-yearly or annual basis. Ocular manifestations were documented and visual acuity was assessed as far as was possible. RESULTS: 1,506 seroconversions were diagnosed during pregnancy, and 327 of the live-born offspring were seropositive for CT. At the end of the study period, ocular manifestations occurred in 79 of the children (24 %), and in 7 cases (9 %) they were discovered during the first month of life. In 72 of the patients (91 %), the ocular manifestations developed between 1 and 151 months (median follow-up time: 6.3 +/- 3.7 years; range: 0.5 - 14 years) under medical treatment for the first year of life. At the end of the study period, information regarding visual acuity was available for 66 patients. In 55 of these (83 %), visual acuity was normal in both eyes, and in 11 (17 %), it was reduced below 0.5. In 1 child, both eyes were functionally affected, one severely. CONCLUSION: CT may not become manifest ocularly until after a decade, which underlines the necessity for long-term ophthalmological monitoring of the infected individuals. In our patients, the prognostic outcome after therapy for the first year of life was better than that reported in the literature. This favourable outcome may serve as a basis for patient counselling.

Comparative diagnostic performance of two commercial rapid tests for malaria in a non-endemic area.

In the study reported here, the diagnostic performance of two new rapid tests for the diagnosis of malaria was evaluated in symptomatic patients in a non-endemic area. Of 557 consecutive patients, 109 (19.6%) had documented malaria. For the NOW ICT MALARIA P.f./P.v. (Binax, Portland, ME, USA) and OptiMAL IT (Diamed, Cressier, Switzerland) tests, respectively, sensitivity values were 96.3% and 79.8% (P-value, 0.0001), and specificity values were 98.8% and 98.4%. The NOW ICT test did not detect two of 80 Plasmodium falciparum infections, and it generated false-positive results for five patients. The OptiMAL IT test failed to detect ten of the P. falciparum infections, and it generated seven false-positive results. The results suggest that these rapid diagnostic tests for malaria may be useful, but they cannot replace microscopic examination of blood films.