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Guitard J, Brenier-Pinchart MP, Varlet-Marie E, Dalle F, Rouges C, Argy N, Bonhomme J, Capitaine A, Guégan H, Lavergne RA, Dardé ML, Pelloux H, Robert-Gangneux F, Yera H, Sterkers Y. Multicenter evaluation of the Toxoplasma gondii Real-TM (Sacace) kit performance for the molecular diagnosis of toxoplasmosis. J Clin Microbiol 2024; 62:e0142823. [PMID: 38470023 PMCID: PMC11005372 DOI: 10.1128/jcm.01428-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 02/20/2024] [Indexed: 03/13/2024] Open
Abstract
The molecular detection of Toxoplasma gondii DNA is a key tool for the diagnosis of disseminated and congenital toxoplasmosis. This multicentric study from the Molecular Biology Pole of the French National Reference Center for toxoplasmosis aimed to evaluate Toxoplasma gondii Real-TM PCR kit (Sacace). The study compared the analytical and clinical performances of this PCR assay with the reference PCRs used in proficient laboratories. PCR efficiencies varied from 90% to 112%; linearity zone extended over four log units (R2 > 0.99) and limit of detection varied from 0.01 to ≤1 Tg/mL depending on the center. Determined on 173 cryopreserved DNAs from a large range of clinical specimens, clinical sensitivity was 100% [106/106; 95 confidence interval (CI): 96.5%-100%] and specificity was 100% (67/67; 95 CI: 94.6%-100%). The study revealed two potential limitations of the Sacace PCR assay: the first was the inconsistency of the internal control (IC) when added to the PCR mixture. This point was not found under routine conditions when the IC was added during the extraction step. The second is a lack of practicality, as the mixture is distributed over several vials, requiring numerous pipetting operations. Overall, this study provides useful information for the molecular diagnosis of toxoplasmosis; the analytical and clinical performances of the Sacace PCR kit were satisfactory, the kit having sensitivity and specificity similar to those of expert center methods and being able to detect low parasite loads, at levels where multiplicative analysis gives inconsistently positive results. Finally, the study recommends multiplicative analysis in particular for amniotic fluids, aqueous humor, and other single specimens.
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Affiliation(s)
- Juliette Guitard
- Sorbonne University, INSERM, Centre de Recherche Saint-Antoine, Assistance Publique-Hôpitaux de Paris, Saint-Antoine Hospital Parasitology-Mycology Laboratory, Paris, France
- Molecular Biology group of the French National Reference Center for Toxoplasmosis, Montpellier, France
| | - Marie-Pierre Brenier-Pinchart
- Molecular Biology group of the French National Reference Center for Toxoplasmosis, Montpellier, France
- Parasitology-Mycology Laboratory, CHU Grenoble Alpes, Grenoble Alpes University, Grenoble, France
| | - Emmanuelle Varlet-Marie
- Molecular Biology group of the French National Reference Center for Toxoplasmosis, Montpellier, France
- Department of Parasitology-Mycology, University of Montpellier, CNRS, IRD, University Hospital Center (CHU) of Montpellier, MiVEGEC, Montpellier, France
| | - Frédéric Dalle
- Molecular Biology group of the French National Reference Center for Toxoplasmosis, Montpellier, France
- Parasitology-Mycology Laboratory, CHU Dijon, Dijon, France
| | - Celia Rouges
- Parasitology-Mycology Laboratory, Cochin Hospital, Paris, France
| | - Nicolas Argy
- Parasitology-Mycology Laboratory, Bichat Hospital, Paris, France
| | - Julie Bonhomme
- Parasitology-Mycology Laboratory, CHU Caen Normandie, Caen, France
| | - Agathe Capitaine
- Parasitology-Mycology Laboratory, CHU Caen Normandie, Caen, France
| | - Hélène Guégan
- Molecular Biology group of the French National Reference Center for Toxoplasmosis, Montpellier, France
- Parasitology-Mycology Laboratory, CHU Rennes, Rennes, France
| | - Rose-Anne Lavergne
- Nantes Université, CHU Nantes, Cibles et Médicaments des Infections et de l’Immunité, IICiMed, UR, Nantes, France
| | | | - Hervé Pelloux
- Molecular Biology group of the French National Reference Center for Toxoplasmosis, Montpellier, France
- Parasitology-Mycology Laboratory, CHU Grenoble Alpes, Grenoble Alpes University, Grenoble, France
| | - Florence Robert-Gangneux
- Molecular Biology group of the French National Reference Center for Toxoplasmosis, Montpellier, France
- Parasitology-Mycology Laboratory, CHU Rennes, Rennes, France
| | - Hélène Yera
- Parasitology-Mycology Laboratory, Cochin Hospital, Paris, France
- Parasitology-Mycology Laboratory, CHU Limoges, Limoges, France
| | - Yvon Sterkers
- Molecular Biology group of the French National Reference Center for Toxoplasmosis, Montpellier, France
- Parasitology-Mycology Laboratory, Cochin Hospital, Paris, France
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Recent advances on the piezoelectric, electrochemical, and optical biosensors for the detection of protozoan pathogens. Trends Analyt Chem 2022. [DOI: 10.1016/j.trac.2022.116803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Brenier-Pinchart MP, Filisetti D, Cassaing S, Varlet-Marie E, Robert-Gangneux F, Delhaes L, Guitard J, Yéra H, Bastien P, Pelloux H, Sterkers Y. Molecular Diagnosis of Toxoplasmosis: Multicenter Evaluation of the Toxoplasma RealCycler Universal PCR Assay on 168 Characterized Human Samples. J Mol Diagn 2022; 24:687-696. [PMID: 35452843 DOI: 10.1016/j.jmoldx.2022.03.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 01/20/2022] [Accepted: 03/04/2022] [Indexed: 10/18/2022] Open
Abstract
Real-time PCR plays a crucial role in the diagnosis of toxoplasmosis. In this multicenter study, the Toxoplasma RealCycler Universal assay was assessed for the diagnosis of toxoplasmosis by eight reference laboratories. DNAs from diverse clinical samples were included: 141 characterized samples from patients with different clinical forms of proven toxoplasmosis and 27 from patients without toxoplasmosis were tested in duplicate with the commercial assay. Final diagnosis was affirmed by each center by analysis of clinical settings and biological follow-up. Calibrated Toxoplasma gondii standards and 11 external quality control samples were also included. Discrepant results observed after the first run of commercial PCR were controlled by both reference and commercial PCR assays. Using the commercial assay, the detection threshold varied from 0.01 to 1 tachyzoites/mL, depending on the center. The relationship between crossing point and DNA concentration was linear over 4 log units (r2 > 0.99), and PCR efficiencies were satisfactory (89% to 104%). The results of the 11 external quality control samples were concordant after one retesting, but those for 3 clinical samples remained discrepant. Sensitivity and specificity were calculated at 97.8% (95% CI, 97.8%-100%) and 100% (95% CI, 87.2%-100%), respectively. Provided that PCRs are performed at least in duplicate to detect low parasitic loads, Toxoplasma RealCycler Universal PCR showed suitable performances to diagnose the different forms of toxoplasmosis.
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Affiliation(s)
- Marie-Pierre Brenier-Pinchart
- Parasitology-Mycology Laboratory, Centre Hospitalier Universitaire Grenoble Alpes and University of Grenoble Alpes, Grenoble, France; "Molecular Biology" Pole of the National Reference Center for Toxoplasmosis, Montpellier, France.
| | - Denis Filisetti
- "Molecular Biology" Pole of the National Reference Center for Toxoplasmosis, Montpellier, France; Parasitology-Medical Mycology Laboratory, Parasitology and Tropical Diseases Institute, University Hospitals and University of Strasbourg, Strasbourg, France
| | - Sophie Cassaing
- "Molecular Biology" Pole of the National Reference Center for Toxoplasmosis, Montpellier, France; Parasitology-Mycology Laboratory, Centre Hospitalier Universitaire de Toulouse and University of Toulouse, Toulouse, France
| | - Emmanuelle Varlet-Marie
- "Molecular Biology" Pole of the National Reference Center for Toxoplasmosis, Montpellier, France; Parasitology-Mycology Department, Centre Hospitalier Universitaire de Montpellier, Montpellier, France
| | - Florence Robert-Gangneux
- "Molecular Biology" Pole of the National Reference Center for Toxoplasmosis, Montpellier, France; Centre Hospitalier Universitaire de Rennes and Ecole des Hautes Etudes en Santé Publique, University of Rennes, Rennes, France
| | - Laurence Delhaes
- "Molecular Biology" Pole of the National Reference Center for Toxoplasmosis, Montpellier, France; Parasitology-Mycology Laboratory, Centre Hospitalier Universitaire de Bordeaux and Cardio-Thoracic Research Center, University of Bordeaux, Bordeaux, France
| | - Juliette Guitard
- "Molecular Biology" Pole of the National Reference Center for Toxoplasmosis, Montpellier, France; Parasitology Mycology Department, Saint-Antoine Hospital, Assistance Publique-Hôpitaux de Paris and Saint-Antoine Research Center, Sorbonne University, Paris, France
| | - Hélène Yéra
- "Molecular Biology" Pole of the National Reference Center for Toxoplasmosis, Montpellier, France; Parasitology-Mycology Laboratory, Cochin Hospital, Assistance Publique-Hôpitaux de Paris and University of Paris, Paris, France
| | - Patrick Bastien
- "Molecular Biology" Pole of the National Reference Center for Toxoplasmosis, Montpellier, France; Parasitology-Mycology Department, Centre Hospitalier Universitaire de Montpellier and MiVEGEC, Institut de Recherche pour Le Développement, University of Montpellier, Montpellier, France
| | - Hervé Pelloux
- "Molecular Biology" Pole of the National Reference Center for Toxoplasmosis, Montpellier, France; Parasitology-Mycology Laboratory, Centre Hospitalier Universitaire Grenoble Alpes and University of Grenoble Alpes, Grenoble, France
| | - Yvon Sterkers
- "Molecular Biology" Pole of the National Reference Center for Toxoplasmosis, Montpellier, France; Parasitology-Mycology Department, Centre Hospitalier Universitaire de Montpellier and MiVEGEC, Institut de Recherche pour Le Développement, University of Montpellier, Montpellier, France
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Seroprevalence and molecular characterization of Toxoplasma gondii infecting ruminants in the North-West of Egypt. Acta Trop 2022; 225:106139. [PMID: 34562431 DOI: 10.1016/j.actatropica.2021.106139] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 09/14/2021] [Accepted: 09/14/2021] [Indexed: 11/20/2022]
Abstract
Toxoplasma gondii is a coccidian parasite known for its heavy toll on people and livestock. It can cause abortion and a variety of congenital diseases. The current study aimed to examine some seroprevalence and molecular attributes of T. gondii obtained from ruminants in the North-West of Egypt. Specimens were random selected from five different locations in Alexandria and Matrouh governorates. A total of 483 blood samples, collected from 96 mixed flocks, were screened for anti-T. gondii IgG antibodies using enzyme-linked immunosorbent assay (ELISA). The seropositive results were then confirmed using polymerase chain reaction (PCR) primers for the B1 and P30 genes. Specific PCR products were selected for sequencing and alignment against the GenBank, where phylogeny has been examined using the maximum likelihood, neighbor-joining, and maximum parsimony in MEGA6. ELISA confirmed the presence of T. gondii in 188 of the investigated samples (38.92%), indicating a higher prevalence in camels (64.51%) and sheep (43.75%) as compared to goats (27.93 %) and cattle (13.46%). PCR confirmed the presence of T. gondii-specific sequences in 159 seropositive specimens, with homology between 98.3 and 100%. The genetic distances between the investigated variants ranged from 0.1 to 0.9, and 7 single nucleotide polymorphisms (SNPs), were identified in the examined T. gondii specimens. The camel T. gondii parasite, isolated from Matrouh, showed a 100% homology with the most dangerous reference strains of T. gondii-RH in the GenBank. Our results showed that B1 and P30-specific PCR could detect T. gondii in blood samples more accurately than ELISA. In addition, the statistical analysis of our data indicated that species, age, sex, and animal location were all risk factors for toxoplasmosis. These findings are likely to boost disease control and help contain the spread of T. gondii infections.
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Robert MG, Brenier-Pinchart MP, Garnaud C, Fricker-Hidalgo H, Pelloux H. Molecular diagnosis of toxoplasmosis: recent advances and a look to the future. Expert Rev Anti Infect Ther 2021; 19:1529-1542. [PMID: 34112045 DOI: 10.1080/14787210.2021.1941867] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
INTRODUCTION Toxoplasmosis is a globally distributed parasitic infection that can be particularly severe when opportunistic or congenital. Its diagnosis requires accurate and rapid techniques that rely mainly on serology and molecular methods. AREAS COVERED The aim of this review was to discuss the positioning of the molecular diagnosis of toxoplasmosis according to the different clinical situations possibly resulting from infection with T. gondii, and to detail recent developments in this technique. The English and French literature were searched with the following keywords: 'Toxoplasmosis', "Molecular diagnosis" and 'PCR'. EXPERT OPINION Molecular techniques have revolutionized the diagnosis of toxoplasmosis, and practices have considerably evolved over the past decades. However, there is still a high degree of inter-laboratory heterogeneity which impairs comparisons between results and studies. Efforts to standardize practices are underway.
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Affiliation(s)
- Marie Gladys Robert
- Service de Parasitologie-Mycologie, CHU Grenoble Alpes, Grenoble, France.,Université Grenoble Alpes, Institut pour l'Avancée des Biosciences (IAB), Grenoble, France
| | - Marie-Pierre Brenier-Pinchart
- Service de Parasitologie-Mycologie, CHU Grenoble Alpes, Grenoble, France.,Université Grenoble Alpes, Institut pour l'Avancée des Biosciences (IAB), Grenoble, France.,Centre National de Référence Toxoplasmose - Pôle Biologie Moléculaire, France
| | - Cécile Garnaud
- Service de Parasitologie-Mycologie, CHU Grenoble Alpes, Grenoble, France.,Université Grenoble Alpes, CNRS, CHU Grenoble Alpes, Grenoble INP, TIMC-IMAG, Grenoble, France
| | | | - Hervé Pelloux
- Service de Parasitologie-Mycologie, CHU Grenoble Alpes, Grenoble, France.,Université Grenoble Alpes, Institut pour l'Avancée des Biosciences (IAB), Grenoble, France.,Centre National de Référence Toxoplasmose - Pôle Biologie Moléculaire, France
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Multicenter Comparative Assessment of the TIB MolBiol Toxoplasma gondii Detection Kit and Four Laboratory-Developed PCR Assays for Molecular Diagnosis of Toxoplasmosis. J Mol Diagn 2021; 23:1000-1006. [PMID: 34082073 DOI: 10.1016/j.jmoldx.2021.05.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 04/19/2021] [Accepted: 05/06/2021] [Indexed: 11/21/2022] Open
Abstract
Toxoplasmosis can be a life-threatening infection, particularly during pregnancy and in immunocompromised patients. The biological diagnosis of toxoplasmosis is challenging and has been revolutionized by molecular detection methods. This article summarizes the data of a multicenter study involving four centers to assess the performances of a commercial PCR assay as compared with four in-house PCR assays using Toxoplasma gondii standards, 20 external quality control specimens, and 133 clinical samples. This clinical cohort includes well-characterized clinical samples corresponding to different clinical situations: confirmed congenital toxoplasmosis (44 samples), toxoplasmosis in immunocompromised patients (25 samples), and chorioretinitis (5 samples). Furthermore, 59 samples from patients without toxoplasmosis were included as negative controls. The analytical sensitivities of the five methods tested were very similar; and the limit of Toxoplasma DNA detection was around 0.01 T. gondii genome per reaction for all the methods. The overall concordance between the commercial PCR and the four in-house PCR assays was 97.7% (130/133). The clinical sensitivity and specificity were >98% and could be increased for the commercial kit when PCR was performed in multiplicate to detect low parasitic loads. In conclusion, the commercial PCR assay shows suitable performances to diagnose the different clinical forms of toxoplasmosis.
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7
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Nourrisson C, Moniot M, Poirier P, Sterkers Y. Evaluation of Two Commercial Kits on the Automated ELITe InGenius PCR Platform for Molecular Diagnosis of Toxoplasmosis. J Mol Diagn 2021; 23:865-871. [PMID: 33962054 DOI: 10.1016/j.jmoldx.2021.04.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 03/17/2021] [Accepted: 04/08/2021] [Indexed: 10/21/2022] Open
Abstract
Molecular diagnosis of toxoplasmosis is essential for establishing the diagnosis of congenital contaminations and for primary infection or reactivation of immunocompromised patients. An integrated extraction and real-time PCR-based system is of particular interest in this context. Commercial kits for automated extraction and amplification steps are now available. Herein, we assessed two commercial PCR assays for this diagnosis, those of Bio-Evolution and Elitech, on the ELITe InGenius platform. The Bio-Evolution assay showed a specificity and a sensitivity of 100% on clinical samples, but a lower analytical detection threshold than the Elitech assay. The latter showed a specificity of 100% and a sensitivity of 96%. The SP1000 cartridges, which allow DNA extraction from 1 mL of template, showed interesting performances on amniotic fluid samples. Overall, the two kits had good performances on the InGenius platform, which offers a turn-key solution suitable for the molecular diagnosis of toxoplasmosis.
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Affiliation(s)
- Céline Nourrisson
- Department of Parasitology and Mycology, University Hospital Center of Clermont-Ferrand, 3IHP, Clermont-Ferrand, France; University Clermont Auvergne, CNRS, Laboratoire Microorganismes: Génome et Environnement, Clermont-Ferrand, France.
| | - Maxime Moniot
- Department of Parasitology and Mycology, University Hospital Center of Clermont-Ferrand, 3IHP, Clermont-Ferrand, France
| | - Philippe Poirier
- Department of Parasitology and Mycology, University Hospital Center of Clermont-Ferrand, 3IHP, Clermont-Ferrand, France; University Clermont Auvergne, CNRS, Laboratoire Microorganismes: Génome et Environnement, Clermont-Ferrand, France
| | - Yvon Sterkers
- University Montpellier, CNRS, IRD, University Hospital Center of Montpellier, "MiVEGEC", Department of Parasitology-Mycology and Molecular Biology Pole of the National Reference Center for Toxoplasmosis, Montpellier, France
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8
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Mandelbrot L, Kieffer F, Wallon M, Winer N, Massardier J, Picone O, Fuchs F, Benoist G, Garcia-Meric P, L'Ollivier C, Paris L, Piarroux R, Villena I, Peyron F. [Toxoplasmosis in pregnancy: Practical Management]. ACTA ACUST UNITED AC 2021; 49:782-791. [PMID: 33677120 DOI: 10.1016/j.gofs.2021.03.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Indexed: 11/28/2022]
Abstract
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.
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Affiliation(s)
- L Mandelbrot
- AP-HP hôpital Louis-Mourier service de gynécologie-obstétrique, 178, rue des Renouillers, 92700 Colombes France; Université de Paris, Paris, France; Inserm IAME-U1137, Paris, France; FHU PREMA, Paris, France.
| | - F Kieffer
- FHU PREMA, Paris, France; Assistance Publique-hôpitaux de Paris, hôpital Armand Trousseau, Service de néonatologie, Paris, France
| | - M Wallon
- Hospices Civils de Lyon, hôpital de la Croix-Rousse, service de parasitologie-Mycologie Médicale, Lyon, France; INSERM U1028-CNRS UMR 5292, université Claude-Bernard, université Lyon-1, Bron, France
| | - N Winer
- Centre hospitalier universitaire de Nantes, service de gynécologie-obstétrique, et NUN, INRA, UMR 1280, Phan Université de Nantes, 44000 Nantes, France
| | - J Massardier
- INSERM U1028-CNRS UMR 5292, université Claude-Bernard, université Lyon-1, Bron, France; Hospices civils de Lyon, hôpital de la Croix-Rousse, service de gynécologie-obstétrique, Lyon, France
| | - O Picone
- AP-HP hôpital Louis-Mourier service de gynécologie-obstétrique, 178, rue des Renouillers, 92700 Colombes France; Université de Paris, Paris, France; Inserm IAME-U1137, Paris, France; FHU PREMA, Paris, France
| | - F Fuchs
- Service de gynécologie obstétrique CHU de Montpellier, Hopital Arnaud de Villeneuve, 371, avenue du Doyen Gaston-Giraud, 34295 Montpellier Cedex 5, France; Inserm, CESP Centre de recherche en Epidémiologie et Santé des Populations, U1018, Reproduction et Développement de l'enfant, 94807 Villejuif, France; Institut Desbrest d'epidemiologie et de santé publique, UMR inserm - université de Montpellier, Montpellier, France
| | - G Benoist
- Obstetrics and gynecology, Caen university Hospital, 14000 Caen, France
| | - P Garcia-Meric
- Assistance Publique-hôpitaux de Marseille, service de médecine néonatale, hôpital de la Conception, Marseille, France
| | - C L'Ollivier
- Aix Marseille Université, IRD, AP-HM, SSA, VITROME, IHU Méditerranée Infection, Marseille, France
| | - L Paris
- Assistance Publique-hôpitaux de Paris, hôpital Pitié-Salpêtrière, service de Parasitologie, Paris, France
| | - R Piarroux
- Assistance Publique-hôpitaux de Paris, hôpital Pitié-Salpêtrière, service de Parasitologie, Paris, France; Sorbonne Université, IPLESP UMR 1136, inserm, Paris, France
| | - I Villena
- Service de parasitologie-mycologie, centre national de référence de la toxoplasmose, centre de ressources biologiques toxoplasma, CHU Reims, Reims, France; EA 7510, laboratoire parasitologie-mycologie, université Reims Champagne -Ardenne, Reims, France
| | - F Peyron
- Hospices Civils de Lyon, hôpital de la Croix-Rousse, service de parasitologie-Mycologie Médicale, Lyon, France; INSERM U1028-CNRS UMR 5292, université Claude-Bernard, université Lyon-1, Bron, France
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9
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Döşkaya M, Pullukçu H, Karakavuk M, Şahar EA, Taşbakan MS, Taşbakan MI, Yılmaz M, Can H, Döşkaya AD, Gürüz AY. Comparison of an in house and a commercial real-time polymerase chain reaction targeting Toxoplasma gondii RE gene using various samples collected from patients in Turkey. BMC Infect Dis 2019; 19:1042. [PMID: 31823777 PMCID: PMC6902542 DOI: 10.1186/s12879-019-4666-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 11/29/2019] [Indexed: 02/07/2023] Open
Abstract
Background Toxoplasma gondii is an opportunistic protozoan parasite that can infect all warm-blooded animals including humans and cause serious clinical manifestations. Toxoplasmosis can be diagnosed using histological, serological, and molecular methods. In this study, we aimed to detect T. gondii RE gene in various human samples by in house and commercial real time polymerase chain reactions. Methods A total of 38 suspected cases of toxoplasmosis [peripheral blood (n:12), amnion fluid (n:11), tissue (n:9), cerebrospinal fluid (n:5), and intraocular fluid (n:1)] were included to the study. An in house and a commercial RT-PCR were applied to investigate the T. gondii RE gene in these samples. Results The compatibility rate of the two tests was 94.7% (37/38). When the commercial RT-PCR kit was taken as reference, the sensitivity and specificity of in house RT-PCR test was 87.5 and 100%. When the in house RT-PCR test was taken as reference, the commercial RT-PCR kit has 100% sensitivity and 96.8% specificity. Incompatibility was detected in only in a buffy coat sample with high protein content. Conclusions Both the commercial and in house RT-PCR tests can be used to investigate T. gondii RE gene in various clinical specimens with their high sensitivity and specificity. In house RT-PCR assay can be favorable due to cost savings compared to using the commercial test.
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Affiliation(s)
- Mert Döşkaya
- Department of Parasitology, Ege University Faculty of Medicine, 35100, İzmir, Bornova, Turkey
| | - Hüsnü Pullukçu
- Department of Infectious Diseases, Ege University Faculty of Medicine, İzmir, Bornova, Turkey
| | - Muhammet Karakavuk
- Department of Parasitology, Ege University Faculty of Medicine, 35100, İzmir, Bornova, Turkey.,Ege University, Ödemiș Vocational High School, İzmir, Ödemiș, Turkey
| | - Esra Atalay Şahar
- Department of Parasitology, Ege University Faculty of Medicine, 35100, İzmir, Bornova, Turkey.,Department of Biotechnology, Ege University Faculty of Engineering, İzmir, Bornova, Turkey
| | - Mehmet Sezai Taşbakan
- Department of Chest Diseases, Ege University Faculty of Medicine, İzmir, Bornova, Turkey
| | - Meltem Işıkgöz Taşbakan
- Department of Infectious Diseases, Ege University Faculty of Medicine, İzmir, Bornova, Turkey
| | - Mümtaz Yılmaz
- Department of Internal Medicine, Ege University Faculty of Medicine, İzmir, Bornova, Turkey
| | - Hüseyin Can
- Department of Biology, Molecular Biology Section, Ege University Faculty of Sciences, İzmir, Bornova, Turkey
| | - Aysu Değirmenci Döşkaya
- Department of Parasitology, Ege University Faculty of Medicine, 35100, İzmir, Bornova, Turkey.
| | - Adnan Yüksel Gürüz
- Department of Parasitology, Ege University Faculty of Medicine, 35100, İzmir, Bornova, Turkey
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10
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Evaluation of the ELITe InGenius PCR Platform for Detection of Mycoplasma pneumoniae. J Clin Microbiol 2019; 57:JCM.00287-19. [PMID: 30971463 DOI: 10.1128/jcm.00287-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 04/01/2019] [Indexed: 01/31/2023] Open
Abstract
Mycoplasma pneumoniae is the leading cause of bacterial community-acquired pneumonia in persons of all ages. Due to the fastidious nature of this bacterium and the necessary specialized growth media, nucleic acid amplification testing is currently the most reliable means for patient diagnostics. Analytical sensitivity, specificity, reproducibility, and clinical performance of the ELITe InGenius automated PCR platform with its MGB Alert M. pneumoniae real-time PCR research use only reagents (ELITechGroup, Inc., Bothell, WA) were compared with those of a laboratory-developed real-time PCR assay targeting repMp1 for detection of M. pneumoniae The ELITe InGenius PCR assay successfully detected 31 distinct M. pneumoniae clinical isolates and reference strains, and there was no cross-reactivity with other mollicutes, Gram-positive bacteria, or Gram-negative bacteria. In testing 223 clinical samples, the ELITe InGenius PCR showed 95.79% and 99.22% positive and negative agreement with the repMp1 assay, respectively. Additionally, the ELITech platform showed 98.91% positive and 96.95% negative predictive values, and there was no significant difference detected between the two assays (McNemar's test, P = 0.375). The ELITe InGenius PCR assay limit of detection was 0.16 CFU/PCR test or 4.16 genome copies (GCs)/test. Accuracy, instrument ease-of-use, and decreased hands-on time make the ELITe InGenius platform suitable for detection of M. pneumoniae directly from clinical specimens.
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Bier NS, Schares G, Johne A, Martin A, Nöckler K, Mayer-Scholl A. Performance of three molecular methods for detection of Toxoplasma gondii in pork. Food Waterborne Parasitol 2019; 14:e00038. [PMID: 32095606 PMCID: PMC7034005 DOI: 10.1016/j.fawpar.2019.e00038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 01/28/2019] [Accepted: 02/04/2019] [Indexed: 11/29/2022] Open
Abstract
Comparison of epidemiological data on the occurrence of Toxoplasma (T.) gondii tissue cysts in meat is hampered by the lack of standardization and a great variety of methods for molecular detection. Therefore, this study aimed to compare and validate three different polymerase chain reaction (PCR) methods for detection of T. gondii DNA in pork. Analytical performance characteristics of two real time PCRs (qPCRs; Tg-qPCR1, Tg-qPCR2) and one conventional endpoint PCR (cPCR), all targeting the 529 repeated element, were assessed using genomic DNA of three clonal T. gondii types prevailing in Europe and North America. qPCR efficiencies for all three clonal types ranged between 93.8 and 94.4% (Tg-qPCR1) and 94.3–95.6% (Tg-qPCR2). Tg-qPCR1 and Tg-qPCR2 showed an overall PCR performance score of 85% and displayed a similar 95% detection limit of 1.067 and 1.561 genome equivalents per PCR reaction (GE/PCR), respectively. However, T. gondii DNA could be detected at concentrations as low as 0.1 GE/PCR. Reliable quantification is possible over 4 log ranges from 105 to 100 GE/PCR with mean repeatability relative standard deviations of ≤11% and reproducibility relative standard deviations of ≤12.7%. Presumably, both qPCRs are similarly suitable for sensitive and specific detection of T. gondii DNA in pork. In contrast, the cPCR using primer pair TOX5/Tox-8 proved to be highly sensitive with a detection limit of 1.41 GE/PCR, but not suitable for detection of T. gondii DNA in pork as unspecific amplification of porcine DNA was observed resulting in bands with similar size to the desired T. gondii-specific PCR product. Comparison of two real time PCRs and one conventional PCR targeting the 529 RE. Both real time PCRs show comparable performance and can be considered equivalent. qPCRs show 95% detection limits of 1.067 and 1.561 genome equivalents per PCR. Reliable quantification is possible over 4 log ranges from 105 to 100 GE/PCR. cPCR using primer pair TOX5/Tox-8 showed non-specific amplification of porcine DNA.
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Affiliation(s)
- Nadja S Bier
- German Federal Institute for Risk Assessment (BfR), Department for Biological Safety, Berlin, Germany
| | - Gereon Schares
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald, Insel Riems, Germany
| | - Annette Johne
- German Federal Institute for Risk Assessment (BfR), Department for Biological Safety, Berlin, Germany
| | - Annett Martin
- German Federal Institute for Risk Assessment (BfR), Department for Exposure, Berlin, Germany
| | - Karsten Nöckler
- German Federal Institute for Risk Assessment (BfR), Department for Biological Safety, Berlin, Germany
| | - Anne Mayer-Scholl
- German Federal Institute for Risk Assessment (BfR), Department for Biological Safety, Berlin, Germany
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Vidal JE. HIV-Related Cerebral Toxoplasmosis Revisited: Current Concepts and Controversies of an Old Disease. J Int Assoc Provid AIDS Care 2019; 18:2325958219867315. [PMID: 31429353 PMCID: PMC6900575 DOI: 10.1177/2325958219867315] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 06/14/2019] [Accepted: 06/28/2019] [Indexed: 01/06/2023] Open
Abstract
Cerebral toxoplasmosis is the most common cause of expansive brain lesions in people living with HIV/AIDS (PLWHA) and continues to cause high morbidity and mortality. The most frequent characteristics are focal subacute neurological deficits and ring-enhancing brain lesions in the basal ganglia, but the spectrum of clinical and neuroradiological manifestations is broad. Early initiation of antitoxoplasma therapy is an important feature of the diagnostic approach of expansive brain lesions in PLWHA. Pyrimethamine-based regimens and trimethoprim-sulfamethoxazole (TMP-SMX) seem to present similar efficacy, but TMP-SMX shows potential practical advantages. The immune reconstitution inflammatory syndrome is uncommon in cerebral toxoplasmosis, and we now have more effective, safe, and friendly combined antiretroviral therapy (cART) options. As a consequence of these 2 variables, the initiation of cART can be performed within 2 weeks after initiation of antitoxoplasma therapy. Herein, we will review historical and current concepts of epidemiology, diagnosis, and treatment of HIV-related cerebral toxoplasmosis.
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Affiliation(s)
- José Ernesto Vidal
- Departamento de Neurologia, Instituto de Infectologia Emílio Ribas, São
Paulo, Brazil
- Departamento de Moléstias Infecciosas e Parasitárias, Hospital das Clínicas
HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
- Laboratório de Investigação Médica em Protozoologia, Bacteriologia e
Resistência Antimicrobiana (LIM 49), Instituto de Medicina Tropical, Universidade de São
Paulo, São Paulo, Brazil
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Risk of congenital toxoplasmosis in women with low or indeterminate anti-Toxoplasma IgG avidity index in the first trimester of pregnancy: an observational retrospective study. Clin Microbiol Infect 2018; 25:761.e9-761.e13. [PMID: 30315959 DOI: 10.1016/j.cmi.2018.09.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 09/28/2018] [Accepted: 09/30/2018] [Indexed: 01/31/2023]
Abstract
OBJECTIVES Congenital toxoplasmosis (CT) affects one to ten fetuses per 10 000 live newborns in western countries. Without knowing pre-conception serostatus, it is hard to date the infection when anti-Toxoplasma IgG and IgM antibodies are positive at first screening. Although a high IgG avidity index (AI) in the first trimester excludes CT, the same cannot be said of intermediate and low AI. The aim of this study was to estimate the risk of CT when intermediate or low AI is detected in the first trimester of pregnancy. METHODS Our observational retrospective study enrolled women with positive anti-Toxoplasma IgG and IgM, and low/intermediate AI in the first trimester of gestation seen at two reference centres in northern Italy between 2006 and 2015. All women received spiramycin. When requested by women, a sample of fluid obtained through amniocentesis was tested with a commercial real-time PCR. CT was defined by positive PCR result confirmed on aborted materials or by newborn follow up. RESULTS Overall, 778 first-trimester pregnant women were included; AI was low in 532/778 (68%) and intermediate in 246/778 (32%). Amniocenteses were performed in 528/778 (67.9%), with no fetal loss. In all, 19/778 (2.4%) miscarriages and 15/778 (1.9%) pregnancy terminations were recorded; 9/778 (1.6%) were lost to follow up. In two women, PCR on amniotic fluid was positive, but CT was confirmed in only 1/747 cases (0.13%, 95% CI 0.02%-0.75%). CONCLUSION In our study, the risk of CT was much lower than anticipated. These data must be considered when counselling these women.
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Saad NM, Hussein AAA, Ewida RM. Occurrence of Toxoplasma gondii in raw goat, sheep, and camel milk in Upper Egypt. Vet World 2018; 11:1262-1265. [PMID: 30410231 PMCID: PMC6200564 DOI: 10.14202/vetworld.2018.1262-1265] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 07/27/2018] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND AND AIM Toxoplasmosis is a worldwide zoonotic disease with harmful effects on animal and human health. Ingestion of contaminated raw milk has been suggested as a vehicle for transmission of Toxoplasma gondii to human. The present study was performed for the detection of T. gondii in raw milk samples of goat, sheep, and camel in Upper Egypt using two different techniques (enzyme-linked immunosorbent assay [ELISA] and quantitative polymerase chain reaction [qPCR]). MATERIALS AND METHODS This study was conducted to determine the T. gondii prevalence using ELISA and qPCR in raw goat, sheep, and camels milk (30 samples for each) collected from different locations in Upper Egypt. RESULTS T. gondii IgG antibodies were detected in 90.0, 60.0, and 3.33% of goat, sheep, and camel milk samples, respectively. From the positive samples of T. gondii IgG, the parasitic DNA was detected only in two examined milk samples, one of them was present in goat milk sample and another one was found in sheep milk sample. On the other hand, the parasite was not detected in camels' milk samples. CONCLUSION These results concluded that the raw milk was contaminated by T. gondii tachyzoites which could be a source of human infection. Restricted hygienic programs should be implemented in the animal farms to decrease the risk of milk contamination by this parasite.
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Affiliation(s)
- Nagah M. Saad
- Department of Food Hygiene (Milk Hygiene), Faculty of Veterinary Medicine, Assiut University, Asyut, Egypt
| | - Asmaa A. A. Hussein
- Department of Animal Hygiene and Zoonoses, Faculty of Veterinary Medicine, Assiut University, Asyut, Egypt
| | - Rania M. Ewida
- Department of Food Hygiene (Milk Hygiene), Faculty of Veterinary Medicine, New Valley Branch, Assiut University, Asyut, Egypt
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Roux G, Varlet-Marie E, Bastien P, Sterkers Y. Evolution of Toxoplasma-PCR methods and practices: a French national survey and proposal for technical guidelines. Int J Parasitol 2018; 48:701-707. [DOI: 10.1016/j.ijpara.2018.03.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 02/27/2018] [Accepted: 03/05/2018] [Indexed: 11/15/2022]
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Dard C, Marty P, Brenier-Pinchart MP, Garnaud C, Fricker-Hidalgo H, Pelloux H, Pomares C. Management of toxoplasmosis in transplant recipients: an update. Expert Rev Anti Infect Ther 2018; 16:447-460. [DOI: 10.1080/14787210.2018.1483721] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Céline Dard
- Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire Grenoble Alpes, Grenoble Cedex France
- Institute for Advanced Biosciences (IAB), Team Host-Pathogen Interactions and Immunity to Infection, INSERM U1209 - CNRS UMR5309, Université Grenoble Alpes, Grenoble France
| | - Pierre Marty
- Faculté de Médecine, Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire de Nice, 06202 Nice, France Université de la Côte d’Azur, Nice, France
- 38043, INSERM U1065, Centre Méditerranéen de Médecine Moléculaire, C3M, Nice, France
| | - Marie-Pierre Brenier-Pinchart
- Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire Grenoble Alpes, Grenoble Cedex France
- Institute for Advanced Biosciences (IAB), Team Host-Pathogen Interactions and Immunity to Infection, INSERM U1209 - CNRS UMR5309, Université Grenoble Alpes, Grenoble France
| | - Cécile Garnaud
- Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire Grenoble Alpes, Grenoble Cedex France
| | - Hélène Fricker-Hidalgo
- Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire Grenoble Alpes, Grenoble Cedex France
| | - Hervé Pelloux
- Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire Grenoble Alpes, Grenoble Cedex France
- Institute for Advanced Biosciences (IAB), Team Host-Pathogen Interactions and Immunity to Infection, INSERM U1209 - CNRS UMR5309, Université Grenoble Alpes, Grenoble France
| | - Christelle Pomares
- Faculté de Médecine, Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire de Nice, 06202 Nice, France Université de la Côte d’Azur, Nice, France
- 38043, INSERM U1065, Centre Méditerranéen de Médecine Moléculaire, C3M, Nice, France
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Varlet-Marie E, Sterkers Y, Perrotte M, Bastien P. A new LAMP-based assay for the molecular diagnosis of toxoplasmosis: comparison with a proficient PCR assay. Int J Parasitol 2018; 48:457-462. [PMID: 29476868 DOI: 10.1016/j.ijpara.2017.11.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 11/11/2017] [Accepted: 11/17/2017] [Indexed: 10/18/2022]
Abstract
Toxoplasmosis is generally a benign infection caused by the protozoan parasite Toxoplasma gondii but can have severe consequences in fetuses of mothers infected during pregnancy (congenital toxoplasmosis) and immunocompromised individuals. PCR-based diagnostic tests have become crucial for its diagnosis. However, this molecular diagnosis essentially relies upon laboratory-developed methods and suffers from a lack of standardization, leading to great variation in methods and performance among laboratories. With the need for accreditation of clinical microbiological laboratories, the use of commercial PCR kits has become an attractive alternative; but thorough evaluation of newly commercialized kits by proficient groups is necessary before any recommendation can be made to parasitology laboratories by health authorities or learned societies. Here, we compared the performance of an original commercial method, the Iam TOXO Q-LAMP (DiaSorin®), using Loop-mediated isothermal amplification (LAMP) technology, with our reference laboratory-developed method using real-time PCR. The kit was first tested using amniotic fluid (AF) and plasma samples (either negative or spiked with live T. gondii tachyzoites at different concentrations (from 7 to 105 tachyzoites/mL)). It was then assessed using a cohort of 11 AF, five placental and 32 blood clinical samples preserved at -20 °C. For the processing of placental/blood samples, a pretreatment step was used, which did not strictly follow the manufacturer's recommendations. The practical ease of use and compliance with good laboratory practices were also evaluated. Although the LAMP assay was less sensitive than the laboratory-developed method at very low parasite concentrations (0.1 T. gondii genome equivalents/mL), the two methods yielded identical results qualitatively and, in some instances, quantitatively, particularly for AF samples.
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Affiliation(s)
- Emmanuelle Varlet-Marie
- CHU (University Hospital Centre) of Montpellier/University of Montpellier, Research Unit "MIVEGEC", CNRS, IRD, Faculty of Medicine, Laboratoire de Parasitologie-Mycologie, Montpellier, France; Pôle "Biologie Moléculaire" du Centre National de Référence de la Toxoplasmose, France; University of Montpellier, Faculty of Pharmacy, Laboratoire de Biophysique & Bioanalyse, Montpellier, France
| | - Yvon Sterkers
- CHU (University Hospital Centre) of Montpellier/University of Montpellier, Research Unit "MIVEGEC", CNRS, IRD, Faculty of Medicine, Laboratoire de Parasitologie-Mycologie, Montpellier, France; Pôle "Biologie Moléculaire" du Centre National de Référence de la Toxoplasmose, France
| | | | - Patrick Bastien
- CHU (University Hospital Centre) of Montpellier/University of Montpellier, Research Unit "MIVEGEC", CNRS, IRD, Faculty of Medicine, Laboratoire de Parasitologie-Mycologie, Montpellier, France; Pôle "Biologie Moléculaire" du Centre National de Référence de la Toxoplasmose, France.
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Yera H, Ménégaut L, Brenier-Pinchart MP, Touafek F, Bastien P, Dalle F. Evaluation of five automated and one manual method for Toxoplasma and human DNA extraction from artificially spiked amniotic fluid. Clin Microbiol Infect 2018; 24:1100.e7-1100.e11. [PMID: 29373837 DOI: 10.1016/j.cmi.2018.01.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Revised: 01/11/2018] [Accepted: 01/13/2018] [Indexed: 11/13/2022]
Abstract
OBJECTIVES Molecular detection of Toxoplasma gondii plays a crucial role in the prenatal and neonatal diagnosis of congenital toxoplasmosis (CT). Sensitivity of this diagnosis is partly related to the efficiency of parasite DNA extraction and amplification. DNA extraction methods with automated platforms have been developed. Therefore, it is essential to evaluate them in combination with adequate PCR amplification assays. METHODS In this multisite study, we investigated the suitability of two recent automated procedures for the isolation of Toxoplasma DNA from amniotic fluid (AF) (Magtration system 12GC, PSS and Freedom EVO VacS, Tecan), compared with three other automated procedures (MagNAPure Compact, Roche, BioRobot EZ1, Qiagen and modified NucliSens easyMAG, bioMérieux) and with the manual DNA extraction QIAamp DNA Mini kit (Qiagen). Two Toxoplasma PCR assays targeting the '529-bp' repeat DNA element were used, based upon dual hybridization (FRET) or hydrolysis (TaqMan) probes. A total of 1296 PCRs were performed including 972 Toxoplasma PCRs. RESULTS We showed variable efficacy (4.2%-100% positive results) among the DNA extraction procedures in isolating up to five T. gondii cells/mL in AF samples. Moreover, for a given DNA extraction method, variable results were obtained among the two Toxoplasma PCR assays for detecting up to five T. gondii cells/mL: when using TaqMan PCR, all the automated systems yielded more than 60% positive results. Nevertheless, when testing the DNA extracts in triplicate, four out of six extraction methods allowed a satisfactory detection of low amounts of T. gondii DNA (≥33% of positive results) independently of the PCR assay used. CONCLUSIONS Despite the influence of the subsequent PCR method used, this study should help microbiologists in the choice of DNA extraction methods for the detection of T. gondii in amniotic fluid. The extraction method should be checked as adequate for the PCR assay used.
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Affiliation(s)
- H Yera
- Université Paris Descartes, AP-HP, Hôpitaux Universitaires Paris Centre, Hôpital Cochin, Laboratory of Parasitology-Mycology, Paris, France; Molecular Biology study group of the French National Reference Centre for Toxoplasmosis, France.
| | - L Ménégaut
- Centre Hospitalier Universitaire de Dijon, Laboratory of Parasitology-Mycology, Dijon, France
| | - M-P Brenier-Pinchart
- Molecular Biology study group of the French National Reference Centre for Toxoplasmosis, France; Centre Hospitalier Universitaire de Grenoble, Université Grenoble Alpes, Laboratory of Parasitology-Mycology, Department of Infectious Agents, Grenoble, France
| | - F Touafek
- Molecular Biology study group of the French National Reference Centre for Toxoplasmosis, France; AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Laboratory of Parasitology-Mycology, Paris, France
| | - P Bastien
- Molecular Biology study group of the French National Reference Centre for Toxoplasmosis, France; Centre Hospitalier Universitaire de Montpellier, Université de Montpellier, Laboratory of Parasitology-Mycology, Montpellier, France
| | - F Dalle
- Molecular Biology study group of the French National Reference Centre for Toxoplasmosis, France; Centre Hospitalier Universitaire de Dijon, Laboratory of Parasitology-Mycology, Dijon, France; UMR PAM, Agrosup, Université de Bourgogne-Franche Comté, Dijon, France
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MOUSAVI P, MIRHENDI H, MOHEBALI M, SHOJAEE S, KESHAVARZ VALIAN H, FALLAHI S, MAMISHI S. Detection of Toxoplasma gondii in Acute and Chronic Phases of Infection in Immunocompromised Patients and Pregnant Women with Real-time PCR Assay Using TaqMan Fluorescent Probe. IRANIAN JOURNAL OF PARASITOLOGY 2018; 13:373-381. [PMID: 30483328 PMCID: PMC6243173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND Toxoplasma gondii, cause severe medical complications in infants and immune-compromised individuals. As using early, sensitive and rapid technique has major in diagnosis of toxoplasmosis, the present study was aimed to detect parasite by using from repetitive element (RE) and B1genes, in blood samples of seropositive immuno-compromised patients and pregnant women. METHODS A total of 110 peripheral blood samples were collected from seropositive cases with anti-T. gondii antibodies, including immunocompromised patients and pregnant women. DNA was extracted by a commercial kit and subjected to TaqMan probe-based real-time PCR assay by using primers and probes specific for RE and B1 genes, separately. The data were analyzed by Kappa test and SPSS-22 software. RESULTS In the pregnant women, 17 (68%) and 14 (56%) samples from 25 IgM+/ IgG+ cases and, 7 (25%) and 6 (21.4%) samples from 28 IgG+/IgM- cases were positive by RE and B1 real time PCR, respectively. Likewise, in immunocompromised group, 20 (66.6%) and 17 (56.6%) samples from 30 IgM+/ IgG+ cases and 2 (7.4%) and 2 (7.4%) samples from 27 IgG+/ IgM- cases were positive by RE and B1 real time PCR, respectively. CONCLUSION Probe-based real time PCR assay is a quantitative approach for early diagnosis of T. gondii infection in clinical samples. Moreover, this method can be more appropriate in diagnosis of acute and reactivated toxoplasmosis. In addition our results indicated that RE gene is more sensitive than B1 gene.
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Affiliation(s)
- Parisa MOUSAVI
- Dept. of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein MIRHENDI
- Dept. of Medical Parasitology and Mycology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mehdi MOHEBALI
- Dept. of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran,Center for Research of Endemic Parasites of Iran, Tehran University of Medical Sciences, Tehran, Iran
| | - Saeedeh SHOJAEE
- Dept. of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein KESHAVARZ VALIAN
- Dept. of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran,Center for Research of Endemic Parasites of Iran, Tehran University of Medical Sciences, Tehran, Iran,Correspondence
| | - Shirzad FALLAHI
- Dept. of Medical Parasitology and Mycology, Faculty of Medicine, Lorestan University of Medical Sciences, Khorramabad, Iran
| | - Setareh MAMISHI
- Dept. of Infectious Diseases, Children Medical Center, Tehran University of Medical Sciences, Tehran, Iran
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Association of Parasite Load Levels in Amniotic Fluid With Clinical Outcome in Congenital Toxoplasmosis. Obstet Gynecol 2017; 130:335-345. [PMID: 28697120 DOI: 10.1097/aog.0000000000002131] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE To correlate neonatal and infant clinical outcome with parasite load in amniotic fluid (AF). METHODS We conducted a retrospective cohort study of 122 children whose mothers had toxoplasmosis during pregnancy. The children were monitored from birth to 12 months old. Stored AF samples were obtained at maternal diagnosis and tested by quantitative polymerase chain reaction. Gestational age at maternal infection, quantitative polymerase chain reaction results, neonatal anti-Toxoplasma gondii immunoglobulin (Ig) M, and clinical outcome at 12 months were correlated. RESULTS Maternal infection occurred in 18 of 122 (14.7%) and 104 of 122 (85.2%) women in the first and second trimesters, respectively. At birth, IgM was present in 107 of 122 (87.7%) neonates and 36 (29.5%) were symptomatic. Of these, half occurred in the first and the other half in the second trimester and 6 of 36 had severe infections (16.7% of symptomatic, 4.9% of total), all infected in the first trimester. Parasite load levels were highly variable (median 35 parasites/mL, range 2-30,473). Logistic regression correlated symptomatic infection with gestational age (odds ratio [OR] 0.47, CI 0.31-0.73) and parasite load (OR 2.04, CI 1.23-3.37), but not with positive IgM (OR 6.81, CI 0.86-53.9). Negative correlations were found between gestational age and parasite load (rs -0.780, CI -0.843 to -0.696), gestational age and symptoms (rs -0.664, CI -0.755 to -0.547), but not gestational age and IgM (rs -0.136, CI -0.311 to 0.048). Parasite load levels distributed by percentile showed that all symptomatic patients appeared from the 75th percentile and all severe infections from the 95th percentile. Load rankings showed doubled the OR for each 20 parasite/mL increment. Parasite load was associated with symptomatic infections (area under the curve 0.959, CI 0.908-0.987) as well as gestational age (area under the curve 0.918, CI 0.855-0.960) and both parameters combined (area under the curve 0.969, CI 0.920-0.992). CONCLUSION Parasite load in AF is associated with the clinical outcome in congenital toxoplasmosis, irrespective of gestational age at maternal infection.
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