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Systemic toxoplasmosis in a cat under cyclosporine therapy. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2021; 23:100542. [PMID: 33678395 DOI: 10.1016/j.vprsr.2021.100542] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 01/22/2021] [Accepted: 01/25/2021] [Indexed: 11/22/2022]
Abstract
Toxoplasma gondii, an obligatory intracellular protozoan parasite infecting warm-blooded animals, can cause toxoplasmosis, a major zoonosis. A male neutered, domestic cat was referred to the Hebrew University Veterinary Teaching Hospital due to dyspnea after long term treatment with cyclosporine for obsessive self-grooming and pruritis. After thorough diagnostics, including non - invasive imaging, broncho-alveolar lavage, blood serology, hematology and biochemistry, and evaluation of the aspirated fluid components, a severe pneumonia and abdominal effusion were detected with observation of free tachyzoites under light microscopy from lavage fluids. PCR and DNA sequencing of broncho-alveolar lavage was positive for T. gondii. Despite aggressive treatment with antibiotics, oxygen supplementation and T. gondii specific antimicrobials, the cat died. It is suggested that potential candidates for cyclosporine be screened for T. gondii antibodies, kept entirely indoors and not fed uncooked meat in order to prevent exposure to T. gondii infection.
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Dupont D, Fricker-Hidalgo H, Brenier-Pinchart MP, Garnaud C, Wallon M, Pelloux H. Serology for Toxoplasma in Immunocompromised Patients: Still Useful? Trends Parasitol 2020; 37:205-213. [PMID: 33046380 DOI: 10.1016/j.pt.2020.09.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 09/11/2020] [Accepted: 09/15/2020] [Indexed: 12/22/2022]
Abstract
Toxoplasmosis represents one of the most common comorbidity factors in solid organ or hematopoietic stem cell transplant recipients as well as in other immunocompromised patients. In the past decades, availability and performance of molecular tools for the diagnosis or the exclusion of toxoplasmosis in these patients have greatly improved. However, if accurately used, serology remains a complementary and essential diagnostic tool for physicians and medical parasitologists for the prevention and management of toxoplasmosis in immunocompromised patients as well. It is required for determination of the immunological status of patients against Toxoplasma. It also helps diagnose and monitor complex cases of opportunistic Toxoplasma infection in immunocompromised patients. New perspectives are available to further enhance their yield and ease of use.
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Affiliation(s)
- Damien Dupont
- Institut des Agents Infectieux, Service de Parasitologie Mycologie Médicale, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, Lyon, 69004, France; Physiologie intégrée du système d'éveil, Centre de Recherche en Neurosciences de Lyon, INSERM U1028-CNRS UMR 5292, Faculté de Médecine, Université Claude Bernard Lyon 1, Bron, 69500, France.
| | - Hélène Fricker-Hidalgo
- Laboratoire de Parasitologie-Mycologie, CHU Grenoble Alpes, Grenoble, 38000, France; Institut pour l'Avancée des Biosciences (IAB), INSERM U1209-CNRS UMR 5309, Université Grenoble Alpes, Grenoble, 38000, France
| | - Marie-Pierre Brenier-Pinchart
- Laboratoire de Parasitologie-Mycologie, CHU Grenoble Alpes, Grenoble, 38000, France; Institut pour l'Avancée des Biosciences (IAB), INSERM U1209-CNRS UMR 5309, Université Grenoble Alpes, Grenoble, 38000, France
| | - Cécile Garnaud
- Laboratoire de Parasitologie-Mycologie, CHU Grenoble Alpes, Grenoble, 38000, France; Université Grenoble Alpes, CNRS, CHU Grenoble Alpes, Grenoble INP, TIMC-IMAG, Grenoble, 38000, France
| | - Martine Wallon
- Institut des Agents Infectieux, Service de Parasitologie Mycologie Médicale, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, Lyon, 69004, France; Physiologie intégrée du système d'éveil, Centre de Recherche en Neurosciences de Lyon, INSERM U1028-CNRS UMR 5292, Faculté de Médecine, Université Claude Bernard Lyon 1, Bron, 69500, France
| | - Hervé Pelloux
- Laboratoire de Parasitologie-Mycologie, CHU Grenoble Alpes, Grenoble, 38000, France; Institut pour l'Avancée des Biosciences (IAB), INSERM U1209-CNRS UMR 5309, Université Grenoble Alpes, Grenoble, 38000, France
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Sah RP, Dey AR, Rahman AKMA, Alam MZ, Talukder MH. Molecular detection of Toxoplasma gondii from aborted fetuses of sheep, goats and cattle in Bangladesh. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2019; 18:100347. [PMID: 31796182 DOI: 10.1016/j.vprsr.2019.100347] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 09/19/2019] [Accepted: 10/31/2019] [Indexed: 12/19/2022]
Abstract
The study was planned to apply the PCR method for detection of T. gondii infection in sheep, goats and cattle aborted fetuses from Mymensingh, Bangladesh. A total of 58 fetal tissue samples (brain, liver, heart, skeletal muscle and placenta) of sheep (5), goats (5) and cattle (2) were selected for study. Aborted fetuses were taken from serologically positive mothers by indirect ELISA. Among them 24 and 34 samples were subjected for PCR assay by using TgB1 and TgTox4 primers respectively. DNA fragments were visualized under UV illumination after gel run. The results demonstrated 15.52% tissue samples from sheep and goat aborted fetuses were positive for T. gondii parasite. Among different tissue samples, brain, liver and heart showed presence of T. gondii parasite. None of tissue samples showed positive in case of cattle. The results of the PCR exhibited that T. gondii infection might be considered as one of the major causative agents for abortion in ewes and does. Further studies are needed to improve our knowledge on different genotypes of T. gondii that infect sheep, goat and cattle population in Bangladesh.
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Affiliation(s)
- Ramesh Prasad Sah
- Department of Parasitology, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh; Agricultural Research Station, Pakhribas, Dhankuta, Nepal Agricultural Research Council, Nepal
| | - Anita Rani Dey
- Department of Parasitology, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | - A K M Anisur Rahman
- Department of Medicine, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | - Mohammad Zahangir Alam
- Department of Parasitology, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
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Microbiologic Diagnosis of Lung Infection. MURRAY AND NADEL'S TEXTBOOK OF RESPIRATORY MEDICINE 2016. [PMCID: PMC7152380 DOI: 10.1016/b978-1-4557-3383-5.00017-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
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Role of bronchoalveolar lavage in the diagnosis of pulmonary infiltrates in immunocompromised patients. Curr Opin Infect Dis 2015; 27:322-8. [PMID: 24977681 DOI: 10.1097/qco.0000000000000072] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW To describe the role of bronchoalveolar lavage (BAL) in the evaluation of pulmonary disease in immunocompromised patients. RECENT FINDINGS Recent discoveries in this field are largely in two areas: the array of diagnostic testing performed on BAL fluid and technical details that can enhance the yield from this procedure. Regarding diagnostic testing, the addition of new assays, including Aspergillus galactomannan antigen assay, respiratory viral panels, and Pneumocystis jirovecii PCR, has improved the diagnostic yield of BAL over conventional cultures and stains. To improve the diagnostic yield of the procedure itself, it should be done early in the clinical course, with the BAL in the anatomic area most affected, and with a preprocedural computed tomography of the chest to properly plan the procedure. SUMMARY Bronchoscopic evaluation with BAL can provide important diagnostic information in immunocompromised patients with pulmonary diseases and should be routinely performed when clinically indicated and able to be completed safely.
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Schmidt M, Sonneville R, Schnell D, Bigé N, Hamidfar R, Mongardon N, Castelain V, Razazi K, Marty A, Vincent F, Dres M, Gaudry S, Luyt CE, Das V, Micol JB, Demoule A, Mayaux J. Clinical features and outcomes in patients with disseminated toxoplasmosis admitted to intensive care: a multicenter study. Clin Infect Dis 2013; 57:1535-41. [PMID: 23994819 DOI: 10.1093/cid/cit557] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Characteristics and outcomes of adult patients with disseminated toxoplasmosis admitted to the intensive care unit (ICU) have rarely been described. METHODS We performed a retrospective study on consecutive adult patients with disseminated toxoplasmosis who were admitted from January 2002 through December 2012 to the ICUs of 14 university-affiliated hospitals in France. Disseminated toxoplasmosis was defined as microbiological or histological evidence of disease affecting >1 organ in immunosuppressed patients. Isolated cases of cerebral toxoplasmosis were excluded. Clinical data on admission and risk factors for 60-day mortality were collected. RESULTS Thirty-eight patients were identified during the study period. Twenty-two (58%) had received an allogeneic hematopoietic stem cell transplant (median, 61 [interquartile range {IQR}, 43-175] days before ICU admission), 4 (10%) were solid organ transplant recipients, and 10 (27%) were infected with human immunodeficiency virus (median CD4 cell count, 14 [IQR, 6-33] cells/µL). The main indications for ICU admission were acute respiratory failure (89%) and shock (53%). The 60-day mortality rate was 82%. Allogeneic hematopoietic stem cell transplant (hazard ratio [HR] = 2.28; 95% confidence interval [CI], 1.05-5.35; P = .04) and systolic cardiac dysfunction (HR = 3.54; 95% CI, 1.60-8.10; P < .01) within 48 hours of ICU admission were associated with mortality. CONCLUSIONS Severe disseminated toxoplasmosis leading to ICU admission has a poor prognosis. Recipients of allogeneic hematopoietic stem cell transplant appear to have the highest risk of mortality. We identified systolic cardiac dysfunction as a major determinant of outcome. Strategies aimed at preventing this fatal opportunistic infection may improve outcomes.
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Affiliation(s)
- Matthieu Schmidt
- Groupe Hospitalier Pitié-Salpêtrière Charles Foix, Service de Pneumologie et Réanimation Médicale
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Osunkalu VO, Akanmu SA, Ofomah NJ, Onyiaorah IV, Adediran AA, Akinde RO, Onwuezobe IA. Seroprevalence of Toxoplasma gondii IgG antibody in HIV-infected patients at the Lagos University Teaching Hospital. HIV AIDS (Auckl) 2011; 3:101-5. [PMID: 22096412 PMCID: PMC3218715 DOI: 10.2147/hiv.s15532] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Toxoplasmosis is caused by infection with a ubiquitous intracellular protozoan parasite, Toxoplasma gondii. With the advent of the HIV pandemic in Nigeria, toxoplasmic encephalitis has become one of the more frequent opportunistic infections and the most commonly implicated cause of focal brain lesions complicating the course of AIDS. OBJECTIVES This study was conducted to compare the pattern of seroprevalence of T. gondii (Toxo-IgG) antibodies among HIV-infected persons presenting with neurological complications and those without. MATERIALS AND METHODS Plasma specimens collected from 380 subjects were tested for Toxo- IgG antibodies by enzyme immunoassay technique and CD4 estimation by flow cytometry. Close-ended questionnaires were applied to all respondents to collect relevant data, with ethical approval from the hospital ethical committee. Plasma was obtained from two study groups comprising 300 HIV-positive respondents without neurological presentations, and 80 HIV-positive respondents with neurological complications. RESULTS Seroprevalence of Toxo-IgG antibodies was 58% in the HIV-positive study group without neurological complications (of these, 79.2% were males and 38.5% were females) and 40% in the study group with neurological complications (46.2% of these were males and 28.6% were females). The overall seroprevalence of Toxo-IgG antibodies among the HIV-positive respondents (with and without neurological complications) was 54.2% (206 of 380). Seroprevalence of Toxo-IgG antibodies was lowest among the educated subjects (19% of the respondents with tertiary education) and among females in both study groups. A higher proportion of the subjects with neurological complications had CD4 cell count <100 cells/μL compared with respondents without neurological defects (39% vs 22.7%; P = 0.000), but the seroprevalence of Toxo-IgG antibodies was higher in subjects without neurological complications (45% vs 31.3%; P = 0.000). CONCLUSION Toxoplasmosis, though an important opportunistic infection in our environment, may not account for the majority of neurological complications observed in patients with HIV infection in our center.
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Affiliation(s)
- Vincent O Osunkalu
- Department of Haematology and Blood Transfusion, College of Medicine Idi-Araba, Lagos, Nigeria
| | - Sulaimon A Akanmu
- Department of Haematology and Blood Transfusion, College of Medicine Idi-Araba, Lagos, Nigeria
| | - Nkolika J Ofomah
- Department of Haematology and Blood Transfusion, College of Medicine Idi-Araba, Lagos, Nigeria
| | - Igwebuike V Onyiaorah
- Department of Histopathology, Nnamdi Azikiwe University, Nnewi Campus, Lagos, Nigeria
| | - Adewumi A Adediran
- Department of Haematology and Blood Transfusion, College of Medicine Idi-Araba, Lagos, Nigeria
| | - Ralph O Akinde
- Department of Morbid Anatomy, College of Medicine Idi-Araba, Lagos, Nigeria
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Moving towards an integrated approach to molecular detection and identification ofToxoplasma gondii. Parasitology 2009; 137:1-11. [DOI: 10.1017/s0031182009991065] [Citation(s) in RCA: 389] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
SUMMARYThe development of simple, sensitive and rapid methods for the detection and identification ofToxoplasma gondiiis important for the diagnosis and epidemiological studies of the zoonotic disease toxoplasmosis. In the past 2 decades, molecular methods based on a variety of genetic markers have been developed, each with its advantages and limitations. The application of these methods has generated invaluable information to enhance our understanding of the epidemiology, population genetics and phylogeny ofT. gondii. However, since most studies focused solely on the detection but not genetic characterization ofT. gondii, the information obtained was limited. In this review, we discuss some widely used molecular methods and propose an integrated approach for the detection and identification ofT. gondii, in order to generate maximum information for epidemiological, population and phylogenetic studies of this key pathogen.
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Okay TS, Yamamoto L, Oliveira LC, Manuli ER, Andrade Junior HFD, Del Negro GMB. Significant performance variation among PCR systems in diagnosing congenital toxoplasmosis in São Paulo, Brazil: analysis of 467 amniotic fluid samples. Clinics (Sao Paulo) 2009; 64:171-6. [PMID: 19330240 PMCID: PMC2666456 DOI: 10.1590/s1807-59322009000300004] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Accepted: 11/01/2008] [Indexed: 12/02/2022] Open
Abstract
INTRODUCTION Performance variation among PCR systems in detecting Toxoplasma gondii has been extensively reported and associated with target genes, primer composition, amplification parameters, treatment during pregnancy, host genetic susceptibility and genotypes of different parasites according to geographical characteristics. PATIENTS A total of 467 amniotic fluid samples from T. gondii IgM- and IgG-positive Brazilian pregnant women being treated for 1 to 6 weeks at the time of amniocentesis (gestational ages of 14 to 25 weeks). METHODS One nested-B1-PCR and three one-round amplification systems targeted to rDNA, AF146527 and the B1 gene were employed. RESULTS Of the 467 samples, 189 (40.47%) were positive for one-round amplifications: 120 (63.49%) for the B1 gene, 24 (12.69%) for AF146527, 45 (23.80%) for both AF146527 and the B1 gene, and none for rDNA. Fifty previously negative one-round PCR samples were chosen by computer-assisted randomization analysis and re-tested (nested-B1-PCR), during which nine additional cases were detected (9/50 or 18%). DISCUSSION The B1 gene PCR was far more sensitive than the AF146527 PCR, and the rDNA PCR was the least effective even though the rDNA had the most repetitive sequence. Considering that the four amplification systems were equally affected by treatment, that the amplification conditions were optimized for the target genes and that most of the primers have already been reported, it is plausible that the striking differences found among PCR performances could be associated with genetic diversity in patients and/or with different Toxoplasma gondii genotypes occurring in Brazil. CONCLUSION The use of PCR for the diagnosis of fetal Toxoplasma infections in Brazil should be targeted to the B1 gene when only one gene can be amplified, preferably by nested amplification with primers B22/B23.
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Affiliation(s)
- Thelma Suely Okay
- Laboratory of Medical Investigation, Instituto da Criança, Faculdade de Medicina da Universidade de São Paulo - São Paulo/SP, Brazil.
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Piña-Vázquez C, Saavedra R, Hérion P. A quantitative competitive PCR method to determine the parasite load in the brain of Toxoplasma gondii-infected mice. Parasitol Int 2008; 57:347-53. [PMID: 18456545 DOI: 10.1016/j.parint.2008.03.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 03/10/2008] [Accepted: 03/13/2008] [Indexed: 11/25/2022]
Abstract
Efficacy of vaccine candidates against toxoplasmosis may be expressed in terms of reduction in cyst number in brains of animals vaccinated and then challenged with a cyst-forming strain of Toxoplasma gondii, compared to non-vaccinated animals. Cyst number generally has been determined by microscopic examination of brain homogenate samples, a technique which has a low sensitivity and is time-consuming. Here we describe a quantitative competitive PCR method, which allows quantifying T. gondii DNA in brain samples. The method uses a primer pair, which allows the amplification of a 301 bp fragment of the 35-fold repeated T. gondii B1 gene and an internal standard (non-homologous competitor) derived from phage lambda, which can be amplified using the same primers and whose size and G/C content are similar to that of the B1 target sequence. The method is sensitive (as few as 10 parasites can be quantified), reproducible, and is not affected by the presence of DNA extracted from mouse brain by means of a simple and rapid technique. It is suitable to quantify the parasite load in the brain of infected mice and to evaluate efficacy of toxoplasmosis vaccine candidates.
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Affiliation(s)
- Carolina Piña-Vázquez
- Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México. México, DF, México
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Kompalic-Cristo A, Frotta C, Suárez-Mutis M, Fernandes O, Britto C. Evaluation of a real-time PCR assay based on the repetitive B1 gene for the detection of Toxoplasma gondii in human peripheral blood. Parasitol Res 2007; 101:619-25. [PMID: 17385062 DOI: 10.1007/s00436-007-0524-9] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2007] [Accepted: 03/12/2007] [Indexed: 11/30/2022]
Abstract
In this paper, we examined the diagnostic value of a real-time polymerase chain reaction (PCR) using fluorescence resonance energy transfer (TaqMan assay) with a new set of primers and probe targeting the B1 gene to reproducibly detect and quantify Toxoplasma gondii in human blood. A total of 183 buffy coat samples from patients serologically classified as recent toxoplasmosis (immunoglobulin M (IgM)+, n = 35) or chronic infection (IgM- and immunoglobulin G (IgG)+, n = 110), and seronegative individuals (n = 38) was investigated. Of the IgM seropositive patients, 17:35 (48.6%) presented parasitaemia, whereas 3.6% positivity was achieved in those individuals that theoretically corresponded to chronic infection (4:110). In the seronegative group, the assay provided 7.9% (3/38) of positive results. Interestingly, one of them was confirmed as positive in a conventional PCR targeting the Toxoplasma B1 gene after hybridization with an internal probe. Real-time PCR was able to accurately quantify the parasite load when concentrations of T. gondii DNA are low, revealing a parasite burden ranged from 9.92 x 10(-3) to 8.73 x 10(-1) tachyzoites genome per milliliter of blood. The chance of an IgM+ patient to present parasitemia detected by the TaqMan procedure was 19.02 times greater than in IgM- individuals (P < 0.05). It was observed a positive association between the optical density values of the IgM serological tests and the number of circulating parasites in the acute patients (P < 0.0001). The specificity of the molecular test was 95.3% when calculated using IgM+ patients as disease group and IgM- as nondisease group. The low sensitivity observed in the IgM seropositive group (48.6%) could be due to the use of buffy coat as clinical material for DNA extraction. An amplification control based on the human beta-actin gene was used in parallel to monitor PCR inhibition and to control for DNA integrity.
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Affiliation(s)
- Alicia Kompalic-Cristo
- Laboratório de Epidemiologia Molecular de Doenças Infecciosas, Departamento de Medicina Tropical, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brazil
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Maubon D, Brenier-Pinchart MP, Fricker-Hidalgo H, Pelloux H. [Real-time PCR in the diagnosis of toxoplasmosis: the way to standardisation?]. ACTA ACUST UNITED AC 2007; 55:304-11. [PMID: 17303349 DOI: 10.1016/j.patbio.2006.11.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2006] [Accepted: 11/15/2006] [Indexed: 11/24/2022]
Abstract
Severity of toxoplasmosis is highly correlated to the immune status of the infected individual. Foetus and immunocompromised patient are mostly at risk to develop life threatening forms. In this situation, serological diagnosis gives poor information. DNA detection using polymerase-chain-reaction technology (PCR) has significantly improved the management of this disease. Even so, the growing number of conventional PCR assays has finally led to variable performance results. Real-Time PCR (RT-PCR) in toxoplasmosis has been developed since 2000. This new technology can improve standardisation. Moreover, quantification of parasitic load in samples becomes possible. This review describes the main RT-PCR procedures actually under use and the studies comparing different target genes. The effective benefit of quantification is also discussed. Reducing number of procedures and more systematic external quality control should be considered, in order to improve reliability in PCR results, which has undoubtedly become a major tool in toxoplasmosis diagnosis.
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Affiliation(s)
- D Maubon
- Parasitologie-mycologie, département des agents infectieux, centre hospitalier universitaire, BP 217, 38043 Grenoble, cedex 09, France.
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Barrs VR, Martin P, Beatty JA. Antemortem diagnosis and treatment of toxoplasmosis in two cats on cyclosporin therapy. Aust Vet J 2006; 84:30-5. [PMID: 16498831 DOI: 10.1111/j.1751-0813.2006.tb13119.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Clinical toxoplasmosis was diagnosed antemortem in two cats being treated with therapeutic doses of cyclosporin. The diagnosis was made by detecting tachyzoites on cytological examination of bronchoalveolar lavage fluid from one case and pleural effusion from the other. Despite early diagnosis and aggressive treatment in both cases, only one cat survived. Reactivation of latent Toxoplasma gondii infection secondary to cyclosporin-induced immunosuppression was considered likely in both cases. The presence of respiratory signs in cats treated with cyclosporin should alert clinicians to the possibility of clinical toxoplasmosis. Consideration should be given to determining the serostatus of cats to T gondii prior to use of drugs which are potent inhibitors of cell mediated immunity, such as cyclosporin. Two cases of feline toxoplasmosis are presented.
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Affiliation(s)
- V R Barrs
- University Veterinary Centre, Faculty of Veterinary Science, The University of Sydney, New South Wales 2006
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Benhamou E, Bretagne S, Soufir L, Lévy Y, Lesprit P. [Interest of Toxoplasma PCR for the early diagnosis of disseminated toxoplasmosis in an HIV-infected patient]. Med Mal Infect 2005; 35:39-41. [PMID: 15695032 DOI: 10.1016/j.medmal.2004.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2004] [Accepted: 09/13/2004] [Indexed: 10/26/2022]
Affiliation(s)
- E Benhamou
- Service d'immunologie clinique, hôpital Henri-Mondor, 51, avenue du Maréchal-de-Lattre, 94010 Créteil, France
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Piao LX, Aosai F, Chen M, Fang H, Mun HS, Norose K, Yano A. A quantitative assay method of Toxoplasma gondii HSP70 mRNA by quantitative competitive-reverse transcriptase-PCR. Parasitol Int 2004; 53:49-58. [PMID: 14984835 DOI: 10.1016/j.parint.2003.11.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2003] [Accepted: 11/13/2003] [Indexed: 10/26/2022]
Abstract
Toxoplasma gondii (T. gondii)-derived heat shock protein 70 (T.g.HSP70) has been identified as a virulent molecule expressing only in T. gondii tachyzoites during lethal acute infection. Therefore, it is of importance to determine the expression of T.g.HSP70 mRNA in a quantitative manner for analysis of virulence of T. gondii in tissues. We have constructed a competitor T.g.HSP70 and have successfully established a quantitative competitive-reverse transcriptase-polymerase chain reaction (QC-RT-PCR) targeting T.g.HSP70 gene. By using the established QC-RT-PCR method, we have demonstrated that the copy number of T.g.HSP70 mRNA per T. gondii tachyzoite was highest in the lung among the organs examined in interferon-gamma knockout (GKO) mice.
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Affiliation(s)
- Lian-Xun Piao
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba 260-8670, Japan
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Shin EH, Kim SB, Nam HW, Han ET, Park JH, Ahn HJ, Chai JY. USE OF MONOCLONAL ANTIBODIES FOR FLOW CYTOMETRIC DETECTION OF INTRACELLULAR TOXOPLASMA GONDII IN MURINE SPLENIC LYMPHOCYTES. J Parasitol 2004; 90:161-6. [PMID: 15040684 DOI: 10.1645/ge-3183] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Various monoclonal antibodies (mAbs) against Toxoplasma gondii RH tachyzoites were used for flow cytometric detection of intracellular parasites in murine splenic lymphocytes. Tg110 and Tg563 (reacting with the major surface protein SAG1), Tg505 (with another surface protein SAG2), Tg695 and Tg786 (with rhoptry proteins), Tg507, Tg621, and Tg317 (with dense granule proteins), Tg536 (with a microneme protein), and Tg685 (with a cytosol antigen) were the mAbs used. After an in vitro infection of lymphocytes with tachyzoites and reactions with the different mAbs, flow cytometry was performed using an indirect immunofluorescent technique. The proportions of whole infected lymphocytes and of each infected lymphocyte phenotype, CD4+ T cells, CD8+ T cells, and B cells, were determined, and their fluorescent intensities were quantified. The best reaction was seen when Tg110 or Tg695 was used as the mAbs. The results suggest that mAbs against surface or rhoptry proteins are highly useful for the flow cytometric detection of intracellular T. gondii in host cells.
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Affiliation(s)
- Eun-Hee Shin
- Department of Parasitology, Seoul National University College of Medicine, and Institute of Endemic Diseases, Seoul National University Medical Research Center, Seoul 110-799, South Korea
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17
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Dawis MA, Bottone EJ, Vlachos A, Burroughs MH. Unsuspected Toxoplasma gondii empyema in a bone marrow transplant recipient. Clin Infect Dis 2002; 34:e37-9. [PMID: 11941570 DOI: 10.1086/339960] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2001] [Revised: 11/13/2001] [Indexed: 11/03/2022] Open
Abstract
Toxoplasma gondii is an opportunistic parasite that can cause severe disease in immunosuppressed individuals. We report a case of unsuspected T. gondii empyema in a bone marrow transplant recipient that was diagnosed by the visualization of numerous intracellular and extracellular tachyzoites in Giemsa- and Gram-stained smears. The patient was treated with pyrimethamine, sulfadiazine, clindamycin, and atovaquone, and she survived 110 days after diagnosis, despite having a large parasite burden.
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Affiliation(s)
- Maria Agnes Dawis
- Department of Pediatrics, Division of Infectious Diseases, Mount Sinai School of Medicine, New York, NY, 10029, USA.
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18
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Abstract
Toxoplasmosis is an anthropozoonotic disease endemic world-wide, caused by the apicomplexan Toxoplasma gondii. Although the course of infection is generally benign, it can cause significant morbidity and mortality in the developing fetus and in immunocompromised individuals. Biological diagnosis classically relies upon serology and direct detection of the parasite by inoculation to laboratory animals. In the past decade, the use of the polymerase chain reaction (PCR) has made a significant improvement in both the prenatal diagnosis of congenital toxoplasmosis and the detection of acute disease in the immunocompromised patient. Nevertheless, like many 'in-house' PCR assays, the PCR-Toxoplasma suffers from lack of standardization and variable performance according to the laboratory. A wide variety of primers has been used in different assays, but few comparative tests have been performed. Moreover, in contrast to other parasitic diseases, PCR-Toxoplasma has not yet attained a sufficient level of sensitivity, regardless of the clinical condition considered. These drawbacks are discussed, together with the undoubted gain that PCR has brought to this difficult diagnosis.
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Affiliation(s)
- Patrick Bastien
- CNRS UMR 5093 Gènome des Protozoaires Parasites, Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire, Faculté de Médecine, 163 Rue A. Broussonet, 34090 Montpellier, France.
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19
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Abstract
Over the past 15 years, there has been a dramatic evolution in molecular approaches to study parasites and parasitic diseases. Many of these advancements have been brought about through the development of new applications of the polymerase chain reaction (PCR). Enhancements in sensitivity that can be achieved using PCR now permit scientists to investigate changes at the level of a single cell, far below what is often needed for parasite-derived applications. PCR has had a substantial impact on advances made in the areas of parasite systematics and epidemiology, immunology and host-parasite interactions, recombinant DNA vaccine development and most recently, the analysis of whole genomes either through directly sequencing the DNA, the analysis of expressed sequence tags (ESTs) or through the rapidly growing field of functional genomics. This paper, however, focuses on the application of PCR methodology to parasite detection and differentiation, and the diagnosis of disease. Specific attention is given to advances provided by multiplex PCR, fluorescence-based "real-time" PCR, and the utilization of PCR as a quantitative technique.
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Affiliation(s)
- D S Zarlenga
- Immunology and Disease Resistance Laboratory, US Department of Agriculture (USDA), ARS, ANRI, Building 1180, BARC-East, Beltsville, MD 20705, USA.
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20
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Kupferschmidt O, Krüger D, Held TK, Ellerbrok H, Siegert W, Janitschke K. Quantitative detection of Toxoplasma gondii DNA in human body fluids by TaqMan polymerase chain reaction. Clin Microbiol Infect 2001; 7:120-4. [PMID: 11318809 DOI: 10.1046/j.1469-0691.2001.00224.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE A new quantitative polymerase chain reaction (real-time PCR) was designed to detect Toxoplasma DNA in human body fluid samples. METHODS Real-time fluorescence detection of amplification product formation on the basis of the TaqMan-System was established with Toxoplasma 18S rDNA as a target gene. RESULTS The method provides a high sensitivity comparable to conventional nested PCR procedures and generates quantitative data when detecting toxoplasmic DNA in human blood, cerebrospinal or amniotic fluid. Moreover, data were obtained investigating blood samples from an immunocompromised patient with reactivated toxoplasmosis after allogeneic bone marrow transplantation, monitoring the therapeutic effect. CONCLUSIONS The potential application of this method to detect Toxoplasma DNA in body fluids and to follow the development of parasitemia under therapy could be demonstrated.
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Affiliation(s)
- O Kupferschmidt
- Robert-Koch-Institut, Parasitologie/Mykologie, Nordufer 20, D-13353 Berlin, Germany.
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21
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Bretagne S, Costa JM, Foulet F, Jabot-Lestang L, Baud-Camus F, Cordonnier C. Prospective study of toxoplasma reactivation by polymerase chain reaction in allogeneic stem-cell transplant recipients. Transpl Infect Dis 2000; 2:127-32. [PMID: 11429023 DOI: 10.1034/j.1399-3062.2000.020305.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Toxoplasmosis is a rare but life-threatening complication of allogeneic stem-cell transplantation. Polymerase chain reaction (PCR) offers the possibility to make the diagnosis earlier than conventional techniques, and is then expected to improve the prognosis. We undertook a prospective screening using a competitive PCR in blood in 32 stem-cell transplant recipients. The sampling covered the first 150 days post-transplant, at days 21, 30, 45, 60, 90, 120, and 150. Twenty-four patients had anti-toxoplasma antibodies before transplant. Three of them (12.5%) had transient PCR-positive samples at 21, 45, and 90 days post-transplant, respectively. The three PCR-positive patients were febrile but had no funduscopic examination or cerebral computerised tomography (CT) scan abnormalities. The PCR signal disappeared when the patients were given trimethoprim-sulfamethoxazole, and no full-blown toxoplasmosis was observed. Toxoplasma reactivation evidenced using PCR is frequent in seropositive patients not receiving trimethoprim-sulfamethoxazole during the 1-3 months post-transplant. Toxoplasma PCR should be included in the diagnostic strategy of fever of unexplained origin in allogeneic stem-cell transplant recipients. Then, prompt specific therapy can be initiated to avoid development of full-blown toxoplasmosis.
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Affiliation(s)
- S Bretagne
- Laboratoire de Parasitologie-Mycologie, Hôpital Henri Mondor, Créteil, France.
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22
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Hafid J, Guichard D, Flori P, Bourlet T, Raberin H, Genin C, Sung RT. Detection of Toxoplasma gondii by polymerase chain reaction in sera of acutely infected mice. J Parasitol 2000; 86:857-9. [PMID: 10958473 DOI: 10.1645/0022-3395(2000)086[0857:dotgbp]2.0.co;2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The presence of Toxoplasma gondii DNA was detected in sera of acutely infected mice by polymerase chain reaction. Adult mice were inoculated intraperitoneally with 5 x 10(3) T. gondii RH strain tachyzoites. Five mice were killed every 3 hr from 3 to 21 hr post infection (PI) and every day from 1 to 7 days PI. Toxoplasma gondii DNA was first detected in 60% of the infected mice 18 hr PI and in 100% of the animals 21 hr PI and from 1 to 7 days PI. No mice survived longer than 7 days.
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Affiliation(s)
- J Hafid
- Groupe immunité des muqueuses et agents pathogènes, Faculté de médecine Jacques Lisfranc, Saint Etienne, France
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23
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Abraham B, Tamby I, Reynes J, Bastien P. Polymerase chain reaction on sputum for the diagnosis of pulmonary toxoplasmosis in AIDS patients. AIDS 2000; 14:910-1. [PMID: 10839608 DOI: 10.1097/00002030-200005050-00027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Homan WL, Vercammen M, De Braekeleer J, Verschueren H. Identification of a 200- to 300-fold repetitive 529 bp DNA fragment in Toxoplasma gondii, and its use for diagnostic and quantitative PCR. Int J Parasitol 2000; 30:69-75. [PMID: 10675747 DOI: 10.1016/s0020-7519(99)00170-8] [Citation(s) in RCA: 508] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We have identified a novel 529bp fragment that is repeated 200- to 300-fold in the genome of Toxoplasma gondii. This 529bp fragment was utilised for the development of a very sensitive and specific PCR for diagnostic purposes, and a quantitative competitive-PCR for the evaluation of cyst numbers in the brains of chronically infected mice. The 529bp fragment was found in all 60 strains of T. gondii tested, and it discriminates DNA of T. gondii from that of other parasites. Toxoplasma gondii DNA was detected in amniotic fluid of patients, as well as in various tissues from infected mice. Polymerase chain reaction with the 529bp fragment was more sensitive than with the 35-copy B1 gene. For the quantitative competitive-PCR, a 410-bp competitor molecule was co-amplified with similar efficiency as the 529bp fragment. Quantitative competitive-PCR produced a linear relationship between the relative amounts of PCR product and the number of tachyzoites in the range of 10(2)-10(4) tachyzoites and 100-3000 tissue cysts. A highly significant correlation between visual counting of brain cysts and quantitative competitive-PCR was obtained in mice chronically infected with Toxoplasma. Thus, quantitative competitive-PCR with the 529bp fragment can be used as an alternative for the tedious visual counting of brain cysts in experimental animals. With the quantitative competitive-PCR, furthermore, we could confirm the copy number of the 529bp fragment in tachyzoites and estimate the number of bradyzoites per cyst.
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Affiliation(s)
- W L Homan
- Microbiological Laboratory for Health Protection, National Institute of Public Health and the Environment, Bilthoven, The Netherlands.
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25
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Franzen C, Altfeld M, Hegener P, Hartmann P, Arendt G, Jablonowski H, Rockstroh J, Diehl V, Salzberger B, Fätkenheuer G. Limited value of PCR for detection of Toxoplasma gondii in blood from human immunodeficiency virus-infected patients. J Clin Microbiol 1997; 35:2639-41. [PMID: 9316922 PMCID: PMC230025 DOI: 10.1128/jcm.35.10.2639-2641.1997] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Cerebral toxoplasmosis is a common, opportunistic, and often life-threatening disease in HIV-infected patients. Diagnosis is supported mainly by clinical evidence and computerized tomography or magnetic resonance imaging scans, but brain images may share features with other brain diseases occurring in HIV-infected patients. To determine the diagnostic value of PCR for the detection of Toxoplasma gondii in blood from HIV-infected patients, we examined 89 blood samples from 59 HIV-infected patients. PCR and Southern blot hybridization were done with DNA extracted from blood samples from 20 patients with confirmed cerebral toxoplasmosis and from 10 patients with suspected but not confirmed cerebral toxoplasmosis. The samples were taken before and 7 to 10 days after the beginning of antiparasitic therapy. For 9 patients who suffered from cerebral toxoplasmosis more than 6 months prior to the study and for 20 patients without any evidence for toxoplasmosis only one blood sample per patient was examined. PCR gave positive results with 5 of the 20 blood samples from patients who suffered from cerebral toxoplasmosis. After 7 to 10 days of therapy PCR results became negative in all these five cases. No amplification was seen with DNA from blood samples from the other 54 patients as the target. The results presented here show that PCR testing of blood samples from HIV-infected patients is of limited value for the diagnosis of cerebral toxoplasmosis. The sensitivity was only 25%, but the specificity was very high (100%), so this technique may be useful for discriminating between cerebral toxoplasmosis and other brain diseases which may be mistaken for toxoplasmosis.
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Affiliation(s)
- C Franzen
- Department of Internal Medicine I, University of Cologne, Germany.
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26
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Angel SO, Matrajt M, Margarit J, Nigro M, Illescas E, Pszenny V, Amendoeira MR, Guarnera E, Garberi JC. Screening for active toxoplasmosis in patients by DNA hybridization with the ABGTg7 probe in blood samples. J Clin Microbiol 1997; 35:591-5. [PMID: 9041395 PMCID: PMC229633 DOI: 10.1128/jcm.35.3.591-595.1997] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
We report the potential use of a specific Toxoplasma gondii DNA probe (ABGTg7). We applied a dot blot hybridization assay to blood samples for the diagnosis of cerebral toxoplasmosis (CT), acute toxoplasmic lymphadenopathy (ATL), and disseminated toxoplasmosis in transplant recipients (TRs). We studied a total of 84 individuals: 38 patients and 46 controls. We found positive hybridization signals for 12 (66.7%) of 18 patients with confirmed CT, 9 (52.9%) of 17 patients with ATL, and 2 (66.7%) of 3 TRs. PCR assays were performed in parallel for patients with ATL, resulting in T. gondii DNA detection for 10 patients (58.8%). A comparative study between dot blot and PCR assays performed with the blood of mice that had been experimentally infected with tachyzoites gave similar results: 60 and 70% positive results, respectively. Finally, the sum of positive values obtained by both DNA tests (dot blot assay plus PCR) increased the rate of positivity for ATL patients to 76.4%. These results demonstrate that the T. gondii ABGTg7 repetitive DNA element is an additional useful resource for diagnosing Toxoplasma parasitemia in patients with CT and ATL and in TRs. Thus, our ABGTg7-based dot blot test may lead to an improvement in T. gondii detection methods in patients with acute toxoplasmosis.
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Affiliation(s)
- S O Angel
- Departamento Parasitología, Instituto Nacional de Microbiología Dr. Carlos G. Malbrán, CP 1281, Buenos Aires, Argentina
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27
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Whelen AC, Persing DH. The role of nucleic acid amplification and detection in the clinical microbiology laboratory. Annu Rev Microbiol 1996; 50:349-73. [PMID: 8905084 DOI: 10.1146/annurev.micro.50.1.349] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Clinical microbiology is in the midst of a new era. Methodology that is based on nucleic acid detection has slowly appeared in the diagnostic laboratory, and is revolutionizing our ability to assist physicians in the diagnosis and management of patients suffering from infectious diseases. Much like the introduction of immunoassays built around hybridoma technology in the 1980s, considerable doubt and promise exist hand in hand in the 1990s. Conventional testing that is technically straight forward, informative, and timely will always be a part of clinical microbiology; however, considerable room for improvement exists with organisms/diseases for which laboratory methods are limited. Nucleic acid methodology will have its greatest and long-awaited impact in this arena.
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Affiliation(s)
- A C Whelen
- Microbiology Service, Brooke Army Medical Center, Fort Sam Houston, San Antonio, Texas 78234, USA
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28
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Ammassari A, Murri R, Cingolani A, De Luca A, Antinori A. AIDS-associated cerebral toxoplasmosis: an update on diagnosis and treatment. Curr Top Microbiol Immunol 1996; 219:209-22. [PMID: 8791702 DOI: 10.1007/978-3-642-51014-4_19] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- A Ammassari
- Department of Infectious Diseases, Catholic University, Rome, Italy
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