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Ikuta K, Kanno R, Bessho T, Koshizuka T, Suzutani T. Evaluation of Toxoplasma gondii IgG avidity assays through a comparison of IgM serostatus. Diagn Microbiol Infect Dis 2023; 105:115901. [PMID: 36889215 DOI: 10.1016/j.diagmicrobio.2023.115901] [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: 07/22/2022] [Revised: 12/23/2022] [Accepted: 01/13/2023] [Indexed: 01/20/2023]
Abstract
Primary Toxoplasma gondii (T. gondii) infection during pregnancy could result in congenital disease with severe clinical complications. IgM antibodies are one of the indices of primary infection. The IgG avidity index (AI) is also known to remain low for at least 3 months after primary infection. Here, we evaluated and compared the performance of T. gondii IgG avidity assays as confirmed by T. gondii IgM serostatus and number of days post-exposure. Four assays preferentially used in Japan were employed to measure the T. gondii IgG AI. Results for the T. gondii IgG AI showed good concordance, particularly in cases with a low IgG AI. This study confirms that the combination of T. gondii IgM and IgG AI tests is a reliable and suitable method for identifying T. gondii primary infections. Our study proposes the necessity of measuring the T. gondii IgG AI as an additional indicator of T. gondii primary infection.
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Affiliation(s)
- Kazufumi Ikuta
- Department of Microbiology, Fukushima Medical University School of Medicine, Fukushima , Japan; Division of Microbiology, Tohoku Medical and Pharmaceutical University School of Medicine, Miyagi, Japan
| | - Ryoko Kanno
- Department of Microbiology, Fukushima Medical University School of Medicine, Fukushima , Japan
| | - Tomoaki Bessho
- Department of Vaccine and Diagnostics, Life Innovation Center, Denka Co., Ltd, Niigata, Japan
| | - Tetsuo Koshizuka
- Department of Microbiology, Fukushima Medical University School of Medicine, Fukushima , Japan; Laboratory of Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan
| | - Tatsuo Suzutani
- Department of Microbiology, Fukushima Medical University School of Medicine, Fukushima , Japan.
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Holec-Gąsior L, Sołowińska K. IgG Avidity Test as a Tool for Discrimination between Recent and Distant Toxoplasma gondii Infection—Current Status of Studies. Antibodies (Basel) 2022; 11:antib11030052. [PMID: 35997346 PMCID: PMC9397011 DOI: 10.3390/antib11030052] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 07/31/2022] [Accepted: 08/11/2022] [Indexed: 11/29/2022] Open
Abstract
Toxoplasma gondii, an obligate intracellular protozoan parasite, is the causative agent of one of the most prevalent zoonoses worldwide. T. gondii infection is extremely important from a medical point of view, especially for pregnant women, newborns with congenital infections, and immunocompromised individuals. Thus, an accurate and proper diagnosis of this infection is essential. Among the available diagnostic tests, serology is commonly used. However, traditional serological techniques have certain limitations in evaluating the duration of T. gondii infection, which is problematic, especially for pregnant women. Avidity of T. gondii-specific IgG antibodies seems to be a significant tool for discrimination between recent and distant infections. This article describes the problem of diagnosis of T. gondii infection, with regard to IgG avidity tests. The IgG avidity test is a useful serological indicator of toxoplasmosis, which in many cases can confirm or exclude the active form of the disease. IgG antibodies produced in the recent primary T. gondii infection are of low avidity while IgG antibodies with high avidity are detected in the chronic phase of infection. Furthermore, this paper presents important topics of current research that concern the usage of parasite recombinant antigens that may improve the performance of IgG avidity tests.
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Oya Y, Futami H, Nakazawa T, Ishijima K, Umemiya K, Takizawa F, Imai N, Kitamura H, Matsumura R. Tubulointerstitial nephritis and uveitis syndrome following meningitis and systemic lymphadenopathy with persistent Toxoplasma immunoglobulin M: a case report. J Med Case Rep 2021; 15:482. [PMID: 34556154 PMCID: PMC8461971 DOI: 10.1186/s13256-021-02909-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 05/17/2021] [Indexed: 01/04/2023] Open
Abstract
Background Tubulointerstitial nephritis and uveitis syndrome is a rare lymphocyte-related oculorenal inflammatory disease presumed to be associated with drug use and infectious agents. Toxoplasma gondii is one of such pathogens that could exhibit encephalitis, meningitis, and uveitis in immunocompromised or in some immunocompetent individuals. If the immunoglobulin M of Toxoplasma is positive on screening, the interpretation of the result is not simple, especially when immunoglobulin M stays positive persistently. Case presentation A 34-year-old Asian male developed fever, headache, and lymphadenopathy with tenderness, which was initially diagnosed as meningitis. Antibiotics were started, and diclofenac sodium was used for the fever. Although his symptoms were alleviated in a week by the treatment, gradual decline in renal function was noted, prompting a renal biopsy that indicated acute granulomatous interstitial nephritis. A week later, tenderness in both eyes with blurred vision appeared and revealed iritis and keratic precipitations in both eyes; hence, the diagnosis of acute tubulointerstitial nephritis and bilateral uveitis syndrome was made. Toxoplasma gondii-specific immunoglobulin G and immunoglobulin M titers were both positive. Although we could not rule out recent infection of Toxoplasma gondii, which may cause uveitis initially, Toxoplasma immunoglobulin G avidity test indicated a distant infection, which allowed us to rule out meningitis and uveitis as responsible for the complication of recent Toxoplasma gondii infection. Drug-induced lymphocyte stimulation test, or lymphocyte transformation test of diclofenac sodium, was solely positive among the tested drugs. Uveitis was alleviated only with ophthalmic steroid, and renal function returned to normal without administration of systemic steroid. Conclusions We experienced a case of diclofenac-induced tubulointerstitial nephritis and uveitis syndrome. In ruling out infections, Toxoplasma immunoglobulin M was persistently positive, and Toxoplasma immunoglobulin G avidity test indicated a “distant” infection. From these two results, we ruled out recent infection. However, it should be noted that “distant” infection indicated by commercial immunoglobulin G avidity is still a multiplex profile consisting of reinfection, reactivation, and latent infection. Narrowing down the infection profile of Toxoplasma is challenging in some cases. Therefore, careful diagnosis and extended follow-up of such patients are needed.
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Affiliation(s)
- Yoshihiro Oya
- Department of Rheumatology, Allergy and Clinical Immunology, National Hospital Organization Chibahigashi National Hospital, 673 Nitona-cho, Chuou-ku, Chiba City, Chiba, 260-8712, Japan. .,Laboratory of Autoimmune diseases, Department of Clinical Research, National Hospital Organization Chibahigashi National Hospital, Chiba City, Chiba, 260-8712, Japan.
| | - Hidekazu Futami
- Department of Rheumatology, Allergy and Clinical Immunology, National Hospital Organization Chibahigashi National Hospital, 673 Nitona-cho, Chuou-ku, Chiba City, Chiba, 260-8712, Japan
| | - Takuya Nakazawa
- Department of Rheumatology, Allergy and Clinical Immunology, National Hospital Organization Chibahigashi National Hospital, 673 Nitona-cho, Chuou-ku, Chiba City, Chiba, 260-8712, Japan
| | - Kazuyuki Ishijima
- Department of Rheumatology, Allergy and Clinical Immunology, National Hospital Organization Chibahigashi National Hospital, 673 Nitona-cho, Chuou-ku, Chiba City, Chiba, 260-8712, Japan
| | - Keiko Umemiya
- Department of Rheumatology, Allergy and Clinical Immunology, National Hospital Organization Chibahigashi National Hospital, 673 Nitona-cho, Chuou-ku, Chiba City, Chiba, 260-8712, Japan
| | - Fumiyoshi Takizawa
- Department of Internal Medicine, Seikeikai Chiba Medical Center, Chiba City, Chiba, 260-0842, Japan
| | - Naoki Imai
- Department of Ophthalmology, National Hospital Organization Chibahigashi National Hospital, Chiba City, Chiba, 260-8712, Japan
| | - Hiroshi Kitamura
- Department of Pathology, National Hospital Organization Chibahigashi National Hospital, Chiba City, Chiba, 260-8712, Japan
| | - Ryutaro Matsumura
- Department of Rheumatology, Allergy and Clinical Immunology, National Hospital Organization Chibahigashi National Hospital, 673 Nitona-cho, Chuou-ku, Chiba City, Chiba, 260-8712, Japan
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Role of Toxoplasma gondii IgG Avidity Testing in Discriminating between Acute and Chronic Toxoplasmosis in Pregnancy. J Clin Microbiol 2020; 58:JCM.00505-20. [PMID: 32321784 DOI: 10.1128/jcm.00505-20] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Risk of mother-to-child transmission of Toxoplasma gondii during pregnancy is much greater in women who are exposed to primary T. gondii infection (toxoplasmosis) after conception compared to those who were exposed to the infection before conception. Therefore, laboratory tests that help classify recent primary toxoplasmosis are important tools for the management of pregnant women suspected to have T. gondii exposure. Detection of Toxoplasma IgM (Toxo IgM) is a sensitive indicator of primary toxoplasmosis, but the indicator specificity is low because sometimes natural IgM antibodies react with Toxoplasma antigens in the absence of the infection. Furthermore, Toxo IgM sometimes persists in blood serum for several months or years following the primary infection. In recent decades, Toxo IgG avidity assay has been used as a standard diagnostic technique for a better estimation of the infection acquisition time and identification of the primary T. gondii infection during pregnancy. Avidity is described as the aggregate strength; by which, a mixture of polyclonal IgG molecules reacts with multiple epitopes of the proteins. This parameter matures gradually within 6 months of the primary infection. A high Toxo IgG avidity index allows a recent infection (less than 4 months) to be excluded, whereas a low Toxo IgG avidity index indicates a probable recent infection with no exclusions of the older infections. This minireview is based on various aspects of T. gondii IgG avidity testing, including (i) description of avidity and basic methods used in primary studies on T. gondii IgG avidity and primary infections; (ii) importance of IgG avidity testing in pregnancy; (iii) result summary of the major studies on the use of T. gondii IgG avidity assay in pregnancy; (iv) brief explanation of the T. gondii IgG avidity values in newborns; (v) result summary of the major studies on T. gondii IgG avidity and PCR; (vi) discussion of commercially available T. gondii IgG avidity assays, including newer automated assays; and (vii) current issues and controversies in diagnosis of primary T. gondii infections in pregnancy.
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Khalil A, Sotiriadis A, Chaoui R, da Silva Costa F, D'Antonio F, Heath PT, Jones C, Malinger G, Odibo A, Prefumo F, Salomon LJ, Wood S, Ville Y. ISUOG Practice Guidelines: role of ultrasound in congenital infection. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2020; 56:128-151. [PMID: 32400006 DOI: 10.1002/uog.21991] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 01/27/2020] [Indexed: 06/11/2023]
Affiliation(s)
- A Khalil
- Fetal Medicine Unit, St George's University Hospitals NHS Foundation Trust, University of London, London, UK
- Vascular Biology Research Centre, Molecular and Clinical Sciences Research Institute, St George's University of London, London, UK
| | - A Sotiriadis
- Second Department of Obstetrics and Gynecology, Faculty of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - R Chaoui
- Center for Prenatal Diagnosis and Human Genetics, Berlin, Germany
| | - F da Silva Costa
- Department of Gynecology and Obstetrics, Ribeirao Preto Medical School, University of São Paulo, Ribeirao Preto, São Paulo, Brazil
- Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
| | - F D'Antonio
- Women's Health and Perinatology Research Group, Department of Clinical Medicine, Faculty of Health Sciences, UiT - The Arctic University of Norway, Tromsø, Norway
- Department of Obstetrics and Gynecology, University Hospital of Northern Norway, Tromsø, Norway
| | - P T Heath
- Paediatric Infectious Diseases Research Group and Vaccine Institute, St George's University of London and St George's University Hospitals NHS Trust, London, UK
| | - C Jones
- Faculty of Medicine and Institute for Life Sciences, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - G Malinger
- Ultrasound Unit, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - A Odibo
- Department of Obstetrics and Gynecology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - F Prefumo
- Division of Obstetrics and Gynecology, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - L J Salomon
- Department of Obstetrics and Fetal Medicine, Hopital Necker-Enfants Malades, Assistance Publique-Hopitaux de Paris, Paris Descartes University, Paris, France
| | | | - Y Ville
- Department of Obstetrics and Fetal Medicine, Hopital Necker-Enfants Malades, Assistance Publique-Hopitaux de Paris, Paris Descartes University, Paris, France
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Garnaud C, Fricker-Hidalgo H, Evengård B, Álvarez-Martínez MJ, Petersen E, Kortbeek LM, Robert-Gangneux F, Villena I, Costache C, Paul M, Meroni V, Guy E, Chiodini PL, Brenier-Pinchart MP, Pelloux H. Toxoplasma gondii-specific IgG avidity testing in pregnant women. Clin Microbiol Infect 2020; 26:1155-1160. [PMID: 32334096 DOI: 10.1016/j.cmi.2020.04.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 04/07/2020] [Accepted: 04/14/2020] [Indexed: 11/30/2022]
Abstract
BACKGROUND The parasite Toxoplasma gondii can cause congenital toxoplasmosis following primary infection in a pregnant woman. It is therefore important to distinguish between recent and past infection when both T. gondii-specific IgM and IgG are detected in a single serum in pregnant women. Toxoplasma gondii-specific IgG avidity testing is an essential tool to help to date the infection. However, interpretation of its results can be complex. OBJECTIVES To review the benefits and limitations of T. gondii-specific avidity testing in pregnant women, to help practitioners to interpret the results and adapt the patient management. SOURCES PubMed search with the keywords avidity, toxoplasmosis and Toxoplasma gondii for articles published from 1989 to 2019. CONTENT Toxoplasma gondii-specific IgG avidity testing remains a key tool for dating a T. gondii infection in immunocompetent pregnant women. Several commercial assays are available and display comparable performances. A high avidity result obtained on a first-trimester serum sample is indicative of a past infection, which occurred before pregnancy. To date, a low avidity result must still be considered as non-informative to date the infection, although some authors suggest that very low avidity results are highly suggestive of recent infections depending on the assay. Interpretation of low or grey zone avidity results on a first-trimester serum sample, as well as any avidity result on a second-trimester or third-trimester serum sample, is more complex and requires recourse to expert toxoplasmosis laboratories. IMPLICATIONS Although used for about 30 years, T. gondii-specific avidity testing has scarcely evolved. The same difficulties in interpretation have persisted over the years. Some authors have proposed additional thresholds to exclude an infection of <9 months, or in contrast to confirm a recent infection. Such thresholds would be of great interest to adapt management of pregnant women and avoid unnecessary treatment; however, they need confirmation and further studies.
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Affiliation(s)
- C Garnaud
- Université Grenoble Alpes, CNRS, Grenoble INP, TIMC-IMAG, Grenoble, France; Parasitology-Mycology, CHU Grenoble Alpes, Grenoble, France.
| | | | - B Evengård
- Department Clinical Microbiology, Umea University, Umea, Sweden
| | - M J Álvarez-Martínez
- Microbiology Department, Hospital Clínic-ISGLOBAL, University of Barcelona, Barcelona, Spain
| | - E Petersen
- Directorate General for Disease Surveillance and Control, Ministry of Health, Oman; Institute for Clinical Medicine, Faculty of Health Science, University of Aarhus, Denmark; ESCMID Emerging Infections Task Force, ESCMID, Basel, Switzerland
| | - L M Kortbeek
- National Institute for Public Health and the Environment; Centre for Infectious Disease Control (CIb) Bilthoven, the Netherlands
| | - F Robert-Gangneux
- Université Rennes, CHU Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé Environnement et Travail)-UMR_S 1085, Rennes, France
| | - I Villena
- Université Reims Champagne-Ardenne EA 7510, CHU Reims, Centre National de Référence de La Toxoplasmose, CRB Toxoplasma, Reims, France
| | - C Costache
- Microbiology Department 'Iuliu Hatieganu', University of Medicine and Pharmacy Cluj-Napoca, Romania
| | - M Paul
- Department and Clinic of Tropical and Parasitic Diseases, University of Medical Sciences, Poznan, Poland
| | - V Meroni
- University Pavia Internal Medicine and Medical Therapy Department, Microbiology and Virology Department IRCCS, Foundation San Matteo Polyclinic, Pavia Italy
| | - E Guy
- Toxoplasma Reference Unit, Public Health Wales Microbiology, Swansea, UK
| | - P L Chiodini
- Hospital for Tropical Diseases and the London School of Hygiene and Tropical Medicine, London, UK
| | - M-P Brenier-Pinchart
- Parasitology-Mycology, CHU Grenoble Alpes, Grenoble, France; Université Grenoble Alpes, INSERM-CNRS, Institute for Advanced Biosciences, Grenoble, France
| | - H Pelloux
- Parasitology-Mycology, CHU Grenoble Alpes, Grenoble, France; Université Grenoble Alpes, INSERM-CNRS, Institute for Advanced Biosciences, Grenoble, France
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Berredjem H, Aouras H, Benlaifa M, Becheker I, Djebar MR. Contribution of IgG avidity and PCR for the early diagnosis of toxoplasmosis in pregnant women from the North-Eastern region of Algeria. Afr Health Sci 2017; 17:647-656. [PMID: 29085392 PMCID: PMC5656190 DOI: 10.4314/ahs.v17i3.7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Background Acute toxoplasmosis in pregnant women presents a high risk of Toxoplasma transmission to the fetus. Early diagnosis is difficult, especially when serological testing for IgG/IgM antibodies fail to differentiate between a recent and a past infection. In this case, we rely on IgG avidity or PCR assays. Objectives The aim of this study was to compare conventional ELISA and IgG avidity, with PCR using B1 and P30 primers for the early diagnosis of toxoplasmosis in pregnant women. Methods Sera were collected from 143 pregnant women and measured by ELISA for anti-Toxoplasma IgG, IgM, IgA and IgG avidity. DNA was extracted from 57 peripheral blood and 14 amniotic fluid samples for PCR amplification. Results A total of 57 out 143 women were seropositive: 30 (52.6%) were IgG+/IgM− and 27 (43.8%) were IgG+/IgM+; IgA antibodies were positive in 7 (12.2%) cases. IgG avidity was low in 9 women suggesting an acute infection; 3 women presented an intermediate avidity. PCR detected Toxoplasma DNA in 9 women presenting low avidity and was negative for the intermediate avidity cases. Conclusion PCR combined to avidity IgG performed better than ELISA IgG, IgM and/or IgA assays alone. PCR was useful in the case of intermediate avidity.
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Affiliation(s)
- Hajira Berredjem
- Department of Biochemistry, Faculty of Sciences, University of Badji Mokhtar, Annaba, Algeria
- Laboratory of Cellular Toxicology, Faculty of Sciences, University of Badji Mokhtar, Annaba, Algeria
| | - Hayette Aouras
- Service of Gynecology, EHS Abdallah Nouaouria Hospital, El Bouni-Annaba, Algeria
| | - Meriem Benlaifa
- Laboratory of Cellular Toxicology, Faculty of Sciences, University of Badji Mokhtar, Annaba, Algeria
| | - Imène Becheker
- Department of Biochemistry, Faculty of Sciences, University of Badji Mokhtar, Annaba, Algeria
| | - Mohamed Reda Djebar
- Laboratory of Cellular Toxicology, Faculty of Sciences, University of Badji Mokhtar, Annaba, Algeria
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Laboudi M, Sadak A. Serodiagnosis of Toxoplasmosis: The effect of measurement of IgG avidity in pregnant women in Rabat in Morocco. Acta Trop 2017; 172:139-142. [PMID: 28433574 DOI: 10.1016/j.actatropica.2017.04.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 04/10/2017] [Accepted: 04/14/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND The diagnosis of Toxoplasmosis in pregnant women during the early first trimester of pregnancy is very important for preventing congenital infection of the fetus; it will not only prevent the risk of transmitting the infection to the fetus but it will also enable to give these women a preventive treatment. In this study, the avidity test was performed on pregnant women during their first prenatal visit at the National Institute of Hygiene in Rabat, Morocco. FINDINGS One hundred and twenty-eight sera samples were collected from 128 pregnant women between August 2015 and June 2016; these women were chosen retrospectively and were in their first four months of pregnancy. The samples were screened using the specific anti-Toxoplasma IgG and IgM antibodies and were subjected to an IgG avidity test. After the serological screening, only 54 women (42.4%) were tested positive for IgG antibodies and five women (3.9%) were tested positive for both anti-Toxoplasma IgG and IgM antibodies. Four IgM-negative women had low-avidity antibodies. However, none of the IgG-avidity test had detected low-avidity antibodies in the five IgM-positive women; three women (60%) had high-avidity antibodies, indicating that the infection was acquired in the distant past. CONCLUSION The avidity test is a helpful tool to exclude a recently acquired toxoplasmosis infection within IgM-positive serum samples in pregnant women during their first trimester of pregnancy. Thus, allowing to perform an appropriate therapeutic intervention.
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Bamba S, Cissé M, Sangaré I, Zida A, Ouattara S, Guiguemdé RT. Seroprevalence and risk factors of Toxoplasma gondii infection in pregnant women from Bobo Dioulasso, Burkina Faso. BMC Infect Dis 2017; 17:482. [PMID: 28693432 PMCID: PMC5504642 DOI: 10.1186/s12879-017-2583-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Accepted: 06/30/2017] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Toxoplasmosis is one of the common worldwide parasitic zoonosis due to Toxoplasma gondii (T. gondii). Toxoplasmosis during pregnancy can result in fetal and neonatal death or various congenital defects. The aim of this study was to assess the seroprevalence and risk factors of T. gondii infection in pregnant women following antenatal care (ANC) services at Bobo Dioulasso. METHODS A cross-sectional study was conducted enrolling a sample of 316 pregnant women attending ANC at centers for maternal and child health of Bobo-Dioulasso town from March 2013 to February 2014. Data on socio-demographic and potential risk factors were collected from each study participant using structured questionnaire through face-to-face interview. Moreover, venous blood specimens were collected and tested for IgM and IgG anti-T. gondii antibodies by enzyme-linked immunosorbent assay and enzyme linked fluorescent assay, respectively. Multivariable logistic regression modeling was used to identify the potential predictor variables for T. gondii infection. RESULTS The overall seroprevalence for T. gondii infection was 31.1% (98/316). All the pregnant women were positive for IgG anti-bodies exclusively. Multivariable logistic regression analysis showed that having at least a secondary education level (AOR = 2.23; 95% CI: [1.04-4.63]); being urban resident (AOR = 2.81; 95% CI: [1.24-6.86]) and the consumption of meat combination (pork + beef + mutton + wild meat + poultry) (AOR = 4.00; 95% CI: [1.06-15.24]) were potential risk factors of T. gondii infection. CONCLUSION Toxoplasmosis is frequent in pregnant women and studies that show incidence of T. gondii among the neonates have to be done to introduce routine antenatal screening program to control congenital toxoplasmosis. There is the need for preventive measures such as education of pregnant women about the transmission routes and prevention methods of toxoplasmosis at ANC clinics.
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Affiliation(s)
- Sanata Bamba
- Université polytechnique de Bobo-Dioulasso, 01 BP 390, Centre MURAZ, Bobo-Dioulasso, Burkina Faso
| | - Mamoudou Cissé
- Université polytechnique de Bobo-Dioulasso, 01 BP 390, Centre MURAZ, Bobo-Dioulasso, Burkina Faso
| | - Ibrahim Sangaré
- Université polytechnique de Bobo-Dioulasso, 01 BP 390, Centre MURAZ, Bobo-Dioulasso, Burkina Faso
| | - Adama Zida
- Université Ouaga 1 Joseph-KI Zerbo, Ouagadougou, Burkina Faso
| | - Souleymane Ouattara
- Université polytechnique de Bobo-Dioulasso, 01 BP 390, Centre MURAZ, Bobo-Dioulasso, Burkina Faso
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Begeman IJ, Lykins J, Zhou Y, Lai BS, Levigne P, El Bissati K, Boyer K, Withers S, Clouser F, Noble AG, Rabiah P, Swisher CN, Heydemann PT, Contopoulos-Ioannidis DG, Montoya JG, Maldonado Y, Ramirez R, Press C, Stillwaggon E, Peyron F, McLeod R. Point-of-care testing for Toxoplasma gondii IgG/IgM using Toxoplasma ICT IgG-IgM test with sera from the United States and implications for developing countries. PLoS Negl Trop Dis 2017. [PMID: 28650970 PMCID: PMC5501679 DOI: 10.1371/journal.pntd.0005670] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Background Congenital toxoplasmosis is a serious but preventable and treatable disease. Gestational screening facilitates early detection and treatment of primary acquisition. Thus, fetal infection can be promptly diagnosed and treated and outcomes can be improved. Methods We tested 180 sera with the Toxoplasma ICT IgG-IgM point-of-care (POC) test. Sera were from 116 chronically infected persons (48 serotype II; 14 serotype I-III; 25 serotype I-IIIa; 28 serotype Atypical, haplogroup 12; 1 not typed). These represent strains of parasites infecting mothers of congenitally infected children in the U.S. 51 seronegative samples and 13 samples from recently infected persons known to be IgG/IgM positive within the prior 2.7 months also were tested. Interpretation was confirmed by two blinded observers. A comparison of costs for POC vs. commercial laboratory testing methods was performed. Results We found that this new Toxoplasma ICT IgG-IgM POC test was highly sensitive (100%) and specific (100%) for distinguishing IgG/IgM-positive from negative sera. Use of such reliable POC tests can be cost-saving and benefit patients. Conclusions Our work demonstrates that the Toxoplasma ICT IgG-IgM test can function reliably as a point-of-care test to diagnose Toxoplasma gondii infection in the U.S. This provides an opportunity to improve maternal-fetal care by using approaches, diagnostic tools, and medicines already available. This infection has serious, lifelong consequences for infected persons and their families. From the present study, it appears a simple, low-cost POC test is now available to help prevent morbidity/disability, decrease cost, and make gestational screening feasible. It also offers new options for improved prenatal care in low- and middle-income countries. Toxoplasmosis, a disease caused by the parasite Toxoplasma gondii, presents a major health burden in both the developed and developing world. Untreated congenital toxoplasmosis causes damage to the eye and brain, but early detection and treatment reduce transmission and disease. Fetal infection can be promptly diagnosed and treated and outcomes can be improved. Gestational screening for toxoplasmosis has international precedent. In this paper, we demonstrated that the new Toxoplasma ICT IgG-IgM test had 100% sensitivity and specificity in detecting Toxoplasma infection (N = 180 U.S. sera from uninfected persons and those with varying parasite serotypes). The use of an inexpensive, easy-to-use point-of-care test facilitates screening of pregnant women for T. gondii infection. In turn, this facilitates prompt treatment for the infection and thereby reduces the health burden caused by this disease. This provides an opportunity to improve maternal-fetal care by using approaches, diagnostic tools, and medicines already available.
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Affiliation(s)
- Ian J. Begeman
- Department of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
| | - Joseph Lykins
- Pritzker School of Medicine, The University of Chicago, Chicago, Illinois, United States of America
| | - Ying Zhou
- Department of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
| | - Bo Shiun Lai
- Department of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
| | - Pauline Levigne
- Institut de Parasitologie et de Mycologie Médicale Hôpital de la Croix Rousse, Lyon, France
| | - Kamal El Bissati
- Department of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
| | - Kenneth Boyer
- Department of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
- Rush University and Medical Center, Chicago, Illinois, United States of America
| | - Shawn Withers
- Department of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
| | - Fatima Clouser
- Department of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
| | - A. Gwendolyn Noble
- Department of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
- Lurie Children’s Hospital and Northwestern University, Chicago, Illinois, United States of America
| | - Peter Rabiah
- Department of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
- Northshore Hospital, Evanston, Illinois, United States of America
| | - Charles N. Swisher
- Department of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
- Lurie Children’s Hospital and Northwestern University, Chicago, Illinois, United States of America
| | - Peter T. Heydemann
- Department of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
- Rush University and Medical Center, Chicago, Illinois, United States of America
| | - Despina G. Contopoulos-Ioannidis
- Department of Pediatrics, Division of Infectious Diseases, Stanford University School of Medicine, Stanford, California, United States of America
| | - Jose G. Montoya
- Palo Alto Medical Foundation Toxoplasma Serology Laboratory, Palo Alto, California, United States of America
- Department of Medicine, Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Yvonne Maldonado
- Department of Pediatrics, Division of Infectious Diseases, Stanford University School of Medicine, Stanford, California, United States of America
- Department of Health Research and Policy, Stanford University School of Medicine, Stanford, California, United States of America
| | - Raymund Ramirez
- Palo Alto Medical Foundation Toxoplasma Serology Laboratory, Palo Alto, California, United States of America
| | - Cindy Press
- Palo Alto Medical Foundation Toxoplasma Serology Laboratory, Palo Alto, California, United States of America
| | | | - François Peyron
- Institut de Parasitologie et de Mycologie Médicale Hôpital de la Croix Rousse, Lyon, France
| | - Rima McLeod
- Department of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
- Department of Pediatrics (Infectious Diseases), Institute of Genomics, Genetics, and Systems Biology, Global Health Center, Toxoplasmosis Center, the Center for Health and the Social Sciences, CHeSS, the College, The University of Chicago, Chicago Medicine, Chicago, Illinois, United States of America
- * E-mail:
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Costa JG, Peretti LE, García VS, Peverengo L, González VDG, Gugliotta LM, Dalla Fontana ML, Lagier CM, Marcipar IS. P35 and P22 Toxoplasma gondii antigens abbreviate regions to diagnose acquired toxoplasmosis during pregnancy: toward single-sample assays. Clin Chem Lab Med 2017; 55:595-604. [PMID: 27658149 DOI: 10.1515/cclm-2016-0331] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 08/16/2016] [Indexed: 11/15/2022]
Abstract
BACKGROUND P35 and P22 Toxoplasma gondii proteins are recognized by specific IgG at the early infection stage, making them ideal for acute toxoplasmosis pregnancy control. Both proteins have been studied to discriminate between acute and chronic toxoplasmosis. However, results were hardly comparable because different protein obtainment procedures led to different antigens, the reference panels used were not optimally typified, and avidity tests were either not performed or narrowly examined. METHODS We bioinformatically predicted P35 and P22 regions with the highest density of epitopes, and expressed them in pET32/BL21DE3 alternative expression system, obtaining the soluble proteins rP35a and rP22a. We assessed their diagnostic performance using pregnant woman serum samples typified as: not infected, NI (IgG-, IgM-), typical-chronic, TC (IgM-, IgG+), presumably acute, A (IgG+, IgM+, low-avidity IgG), and recently chronic, RC (IgG+, IgM+, high-avidity IgG). RESULTS rP35a performed better than rP22a to differentiate A from RC, the areas under the curve (AUC) being 0.911 and 0.818, respectively. They, however, performed similarly to differentiate A from TC+RC (AUC: 0.915 and 0.907, respectively). rP35a and rP22a evaluation by avidity ELISA to discriminate A from RC rendered AUC values of 0.974 and 0.921, respectively. The indirect ELISA and avidity ELISA results analyzed in tandem were consistent with those obtained using commercial kits. CONCLUSIONS rP35a and rP22a features suggest that, with complementary use, they could replace parasite lysate for toxoplasmosis infection screening and for acute toxoplasmosis diagnosis. Our proposal should be validated by a longitudinal study and may lead to a reliable toxoplasmosis pregnancy control, performing tests in only one serum sample.
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Maldonado YA, Read JS. Diagnosis, Treatment, and Prevention of Congenital Toxoplasmosis in the United States. Pediatrics 2017; 139:peds.2016-3860. [PMID: 28138010 DOI: 10.1542/peds.2016-3860] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Interpretation of the Elecsys Toxo IgG avidity results for very low and very high index: study on 741 sera with a determined date of toxoplasmosis. Eur J Clin Microbiol Infect Dis 2016; 36:847-852. [DOI: 10.1007/s10096-016-2870-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 12/06/2016] [Indexed: 11/25/2022]
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Abstract
Toxoplasmosis is caused by a coccidian parasite, Toxoplasma gondii. The parasite is highly prevalent both in humans and in warm-blooded animals. Cat family animals are definitive host, and these animals excrete the infective oocysts in their feces. Humans, though not definitive host, get infection by consuming water or food contaminated with cat feces. Rarely, infection can also take place through transfusing the infected blood, through transplantation of infected organs, or transplacentally from infected mother to fetus. Transplacental infection can cause congenital infection with varied degree of clinical manifestations, which depend on the age of fetus when infection took place. Diagnosis of congenital toxoplasmosis is difficult to establish until it is suspected and laboratory investigations are carried out. In more than 75% of cases, acute infection is missed due to very mild or unnoticeable clinical symptoms and signs. In India, a prevalence rate of 22.4% (8.8-37.3%) has been reported with an overall IgM positivity of 1.43%. It is estimated that approximately between 56,737 and 176,882 children per year are born in India with a possible risk of congenital toxoplasmosis. The diagnosis of congenital toxoplasmosis can be made by serological methods which are most commonly used. The other methods are parasite isolation by culture and molecular methods. Toxoplasmosis is treatable and transplacental transmission can be prevented by spiramycin, which concentrates in the placenta. However, if infection has done any damage to the fetus or the parasite has passed the placenta, spiramycin cannot reverse the damage. Prevention remains the best remedy.
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Affiliation(s)
- Sarman Singh
- Division of Clinical Microbiology and Molecular Medicine, All India Institute of Medical Sciences, New Delhi, India
- Address for correspondence: Prof. Sarman Singh, Division of Clinical Microbiology and Molecular Medicine, All India Institute of Medical Sciences, New Delhi - 110 029, India. E-mail:
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Dard C, Fricker-Hidalgo H, Brenier-Pinchart MP, Pelloux H. Relevance of and New Developments in Serology for Toxoplasmosis. Trends Parasitol 2016; 32:492-506. [PMID: 27167666 DOI: 10.1016/j.pt.2016.04.001] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 04/01/2016] [Accepted: 04/01/2016] [Indexed: 12/26/2022]
Abstract
Toxoplasmosis is a widespread parasitic disease caused by the intracellular parasite Toxoplasma gondii with a wide spectrum of clinical outcomes. The biological diagnosis of toxoplasmosis is often difficult and of paramount importance because clinical features are not sufficient to discriminate between toxoplasmosis and other illnesses. Serological tests are the most widely used biological tools for the diagnosis of toxoplasmosis worldwide. This review focuses on the crucial role of serology in providing answers to the most important questions related to the epidemiology and diagnosis of toxoplasmosis in human pathology. Notwithstanding their undeniable importance, serological tools need to be continuously improved and the interpretation of the ensuing results remains complex in many circumstances.
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Affiliation(s)
- Céline Dard
- Laboratoire de Parasitologie-Mycologie, Centre Hospitalier et Universitaire de Grenoble Alpes, Grenoble, France; Institut Albert Bonniot, INSERM U1209 - CNRS UMR 5309, Université Grenoble Alpes, Grenoble, France.
| | - Hélène Fricker-Hidalgo
- Laboratoire de Parasitologie-Mycologie, Centre Hospitalier et Universitaire de Grenoble Alpes, Grenoble, France
| | - Marie-Pierre Brenier-Pinchart
- Laboratoire de Parasitologie-Mycologie, Centre Hospitalier et Universitaire de Grenoble Alpes, Grenoble, France; Institut Albert Bonniot, INSERM U1209 - CNRS UMR 5309, Université Grenoble Alpes, Grenoble, France
| | - Hervé Pelloux
- Laboratoire de Parasitologie-Mycologie, Centre Hospitalier et Universitaire de Grenoble Alpes, Grenoble, France; Institut Albert Bonniot, INSERM U1209 - CNRS UMR 5309, Université Grenoble Alpes, Grenoble, France
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Satbige AS, Vijaya Bharathi M, Ganesan PI, Sreekumar C, Rajendran C. Detection of Toxoplasma gondii in small ruminants in Chennai using PCR and modified direct agglutination test. J Parasit Dis 2016; 40:1466-1469. [PMID: 27876968 DOI: 10.1007/s12639-015-0713-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 08/31/2015] [Indexed: 11/29/2022] Open
Abstract
A total of 193 sera samples, along with tissues (lung, heart, and brain) collected from 136 sheep and 57 goats from the Corporation slaughter house, Madras Veterinary College teaching hospital, and private mutton shops from Chennai were tested for Toxoplasma gondii. All the sera samples were tested using modified direct agglutination test. Of the 193 sera samples, 57 (29.5 %) had a minimum titre of 1:20, with 30.14 % (41/136) of sheep and 28.07 % (16/57) of goats being seropositive. Tissue samples from all 193 animals, when subjected to B1 based PCR to detect T. gondii DNA, showed 3.67 and 3.50 % to be positive in sheep and goats, respectively. In the present investigation B1 based PCR detected T. gondii in low numbers, possibly due to limitation of the sample size. The presence of T. gondii in tissues of sheep and goats slaughtered for human consumption in Chennai indicates the role of these food animals as potential sources of infection to human.
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Affiliation(s)
| | - M Vijaya Bharathi
- Department of Veterinary Epidemiology and Preventive Medicine, Madras Veterinary College, Vepery, Chennai, Tamilnadu 600 007 India
| | - P I Ganesan
- Department of Veterinary Epidemiology and Preventive Medicine, Madras Veterinary College, Vepery, Chennai, Tamilnadu 600 007 India
| | - C Sreekumar
- PGRIAS, TANUVAS, Kattupakkam, Chennai, 600056 India
| | - C Rajendran
- Defence Food Research Laboratory, Defence Research and Development Organisation (DRDO), Siddarthanagar, Mysore, Karnataka 570 011 India
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Seroprevalence of Toxoplasma gondii in women who have aborted in comparison with the women with normal delivery in Ahvaz, southwest of Iran. ScientificWorldJournal 2015; 2015:764369. [PMID: 25699288 PMCID: PMC4325198 DOI: 10.1155/2015/764369] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2014] [Revised: 12/26/2014] [Accepted: 01/12/2015] [Indexed: 11/17/2022] Open
Abstract
Toxoplasma gondii is an obligate intracellular protozoan parasite causing toxoplasmosis in animals and humans. Primary maternal infection with toxoplasmosis during pregnancy is frequently associated with transplacental transmission to the fetus. However it is not certain whether Toxoplasma infection can cause recurrent abortion. The aim of this study was to determine the relationship between Toxoplasma infection and abortion via detection of anti-Toxoplasma gondii antibodies in sera of women with obstetrical problems and compare the results with control group consisting of women with history of normal delivery. Sera from 130 women with abortion and sera of 130 women with normal delivery were tested for IgG and IgM anti-Toxoplasma gondii antibodies by ELISA method. The present study revealed 24.6% of the samples with abortion and 21.5% of the samples with normal delivery were positive for IgG antibodies. However, statistical analysis indicated no significant differences (P > 0.05). In addition, IgM antibody was detected in one woman who had aborted but not in women with normal childbirth. This study showed no significant difference between the case and control groups in IgG anti-Toxoplasma antibody but detected one sample with IgM antibodies in woman with abortion during the first trimester of pregnancy. In order to determine the relationship between Toxoplasma infection and abortion, anti-Toxoplasma IgG avidity and PCR to discriminate between recent and prior infections are recommended.
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Bamba S, Sourabié Y, Guiguemdé TR, Karou DS, Simporé J, Bambara M, Villena I. Seroprevalence of latent Toxoplasma gondii infection among HIV-infected pregnant women in Bobo-Dioulasso, Burkina Faso. Pak J Biol Sci 2014; 17:1074-1078. [PMID: 26031029 DOI: 10.3923/pjbs.2014.1074.1078] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The deficit of cellular immunity, as found in HIV infected individuals, may lead to the reactivation of latent Toxoplasma gondii cysts, with as consequence, the occurrence of toxoplasmosis and an eventual vertical transmission of the disease during pregnancy. The present study was designed for determining the occurrence of latent Toxoplasma gondii among HIV-infected pregnant women during the first trimester in Bobo-Dioulasso. Thus, 348 pregnant women aged from 17 to 47 years (average age of 6.64 ± 4.75 yaers) were enrolled. The specific anti-Toxoplasma gondii IgG and IgM antibodies were quantified from whole blood specimens using the high-sensitivity direct agglutination and the enzyme linked fluorescent assays, respectively, the IgG avidity test being used for the dating of the primary infection. The results revealed that the seroprevalence of Toxoplasma gondii latent infection was 34.7%. It was significantly higher in HIV-infected women compared with uninfected ones (68,7%; CI 95%: 43,6%-88,9%) versus (33,1%; CI 95%: 28, 2%-38,3%). In addition, all the occurrences of the high IgG avidity were closely linked with the presence of IgM. These results underlined the need for the clinical follow-up of the maternal HIV diseases including the toxoplasmosis during the pregnancy since; the newborns are still exposed to vertical transmission of Toxoplasma infection in endemic areas like Burkina Faso.
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Drapała D, Holec-Gąsior L, Kur J, Ferra B, Hiszczyńska-Sawicka E, Lautenbach D. A new human IgG avidity test, using mixtures of recombinant antigens (rROP1, rSAG2, rGRA6), for the diagnosis of difficult-to-identify phases of toxoplasmosis. Diagn Microbiol Infect Dis 2014; 79:342-6. [DOI: 10.1016/j.diagmicrobio.2014.03.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 03/04/2014] [Accepted: 03/06/2014] [Indexed: 11/26/2022]
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Singh S, Munawwar A, Rao S, Mehta S, Hazarika NK. Serologic prevalence of Toxoplasma gondii in Indian women of child bearing age and effects of social and environmental factors. PLoS Negl Trop Dis 2014; 8:e2737. [PMID: 24675656 PMCID: PMC3967963 DOI: 10.1371/journal.pntd.0002737] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 01/30/2014] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Seroprevalence and incidence of toxoplasmosis in women of child bearing age has remained a contentious issue in the Indian subcontinent. Different laboratories have used different patient recruitment criteria, methods and variable results, making these data difficult to compare. AIM To map the point-prevalence and incidence of toxoplasmosis in India. MATERIAL AND METHODS In this cross-sectional study, a total of 1464 women of fertile age were recruited from 4 regions using similar recruitment plans. This included women from northern (203), southern (512), eastern (250) and western (501) regions of India. All samples were transported to a central laboratory in Delhi and tested using VIDAS technology. Their age, parity, eating habits and other demographic and clinical details were noted. RESULTS Most women were in the 18-25 years age group (48.3%), followed by 26-30 years (28.2%) and 31-35 years (13.66). Few (45) women older than 35 yr. were included. Overall prevalence of anti-Toxoplasma IgG antibodies was seen in 22.40%, with significantly more in married women (25.8%) as compared to single women (4.3%). Prevalence increased steadily with age: 18.1% in the 18-25 yr. age group to 40.5% in women older than 40 yr. The prevalence was high (66%) in those who resided in mud houses. Region-wise, the highest prevalence was observed in South India (37.3%) and the lowest (8.8%) in West Indian women. This difference was highly significant (P<0.001). Prevalence was 21.2% in East India and 19.7% in North India. The IgM positivity rate ranged from 0.4% to 2.9% in four study centers. CONCLUSIONS This pan-India study shows a prevalence rate of 22.4% with a wide variation in four geographical regions ranging from as low as 8.8% to as high as 37.3%. The overall IgM positivity rate was 1.43%, indicating that an estimated 56,737-176,882 children per year are born in India with a possible risk of congenital toxoplasmosis.
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Affiliation(s)
- Sarman Singh
- Division of Clinical Microbiology & Molecular Medicine, Department of Laboratory Medicine, All India Institute of Medical Sciences, New Delhi, India
| | - Arshi Munawwar
- Division of Clinical Microbiology & Molecular Medicine, Department of Laboratory Medicine, All India Institute of Medical Sciences, New Delhi, India
| | - Sugandhi Rao
- Kasturba Medical College, Manipal, Karnataka, India
| | - Sanjay Mehta
- CUS Medical College, Surendra Nagar, Gujarat, India
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Malik A, Rizvi M, Khan F, Khan N, Rabbani T, Khan HM. Toxoplasma gondii in women with bad obstetric history and infertility: a five-year study. ASIAN PACIFIC JOURNAL OF TROPICAL DISEASE 2014. [DOI: 10.1016/s2222-1808(14)60446-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Toxoplasma gondii recombinant antigens as tools for serodiagnosis of human toxoplasmosis: current status of studies. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2013; 20:1343-51. [PMID: 23784855 DOI: 10.1128/cvi.00117-13] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Toxoplasma gondii is a parasitic protozoan which is the cause of toxoplasmosis. Although human toxoplasmosis in healthy adults is usually asymptomatic, serious disease can occur in the case of congenital infections and immunocompromised individuals. Furthermore, despite the exact recognition of its etiology, it still presents a diagnostic problem. Diagnosis of toxoplasmosis is mainly based on the results of serological tests detecting anti-T. gondii-specific antibodies in the patient's serum sample. The specificities and sensitivities of serology tests depend mostly on the diagnostic antigen(s) used. Most of the commercial serological kits currently available are based on Toxoplasma lysate antigens (TLAs). In recent years, many studies showed that recombinant antigenic proteins of T. gondii may be an alternative source of antigens which are very useful for the serodiagnosis of toxoplasmosis. This article presents a review of current studies on the application and usefulness of different T. gondii recombinant antigens in serological tests for the diagnosis of human toxoplasmosis.
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Comparison of the Vidas system and two recent fully automated assays for diagnosis and follow-up of toxoplasmosis in pregnant women and newborns. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2013; 20:1203-12. [PMID: 23740928 DOI: 10.1128/cvi.00089-13] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Serological testing to detect toxoplasmosis is of major importance to avoid the possible effects of the disease in newborns. This study assessed anti-Toxoplasma IgG and IgM with the Vidas (bioMérieux), Architect (Abbott), and Liaison (DiaSorin) systems in 631 sera from pregnant women and newborns as well as anti-Toxoplasma IgG avidity with these three systems on 54 sera from pregnant women with positive IgG and IgM. The IgG and IgM results were in agreement in, respectively, 95.2% and 98.3% (Vidas versus Architect) and 96.9% and 95.3% (Vidas versus Liaison) of the samples. Specificities were excellent for all the assays, while Vidas sensitivities ranged (depending on the classification of gray zone results) from 93.8 to 98.4% for IgG (Architect, 84.4 to 93.8%; Liaison, 93.8%) and from 81.8 to 90.9% for IgM (Architect, 63.6%; Liaison, 81.8 to 90.9%). In seroconversion sequences, IgMs were generally detected simultaneously by the three assays, while Architect was the earliest assay to detect IgG. In noninfected children, maternally transmitted IgGs were detected for a longer time with Architect than with the other systems. IgMs were positive in only one infected child with the Vidas and Liaison systems. Significantly more sera were classified in the high-avidity category with Vidas than with Architect. This evaluation shows similar performances for Vidas and more recent systems. The Vidas system adequately detects toxoplasmosis in pregnant women and newborns. This system fits the needs of laboratories working on small routine series for first-line testing as well as expert laboratories, due to a high specificity and a powerful avidity test.
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Toxoplasma seroconversion with negative or transient immunoglobulin M in pregnant women: myth or reality? A French multicenter retrospective study. J Clin Microbiol 2013; 51:2103-11. [PMID: 23616461 DOI: 10.1128/jcm.00169-13] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Classically, Toxoplasma infection is associated with high levels of specific IgM antibody and a rise in specific IgG levels 1 to 3 weeks later. Atypical IgG seroconversion, without IgM detection or with transient IgM levels, has been described during serologic follow-up of seronegative pregnant women and raises difficulties in interpreting the results. To evaluate the frequency and the characteristics of these atypical cases of seroconversion, an investigation was conducted within the French National Reference Center for Toxoplasmosis, from which 26 cases collected from 12 laboratories belonging to the network were identified. The aim of this work was to retrospectively analyze the results of serologic testing, the treatments administered, and the results of prenatal and postnatal follow-up for these women. In each case, IgG antibodies were detected using both screening and confirmatory tests. IgM antibodies were not detected in 15 cases, and the levels were equivocal or low-positive in 11 cases. The IgG avidity results were low in 16 cases and high in one case. Most of the pregnant women (22/26) were treated with spiramycin from the time that IgG antibodies appeared until delivery. Amniotic fluid was analyzed for Toxoplasma gondii DNA by PCR in 11/26 cases, and the results were negative in all cases. Congenital toxoplasmosis was ruled out in 12/26 newborns. There was no abnormality observed at birth for 10 newborns and no information available for 4 newborns. In conclusion, when the interpretation of serological results is so difficult, it seems cautious to initiate treatment by spiramycin and to follow the pregnant women and their newborns.
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Abstract
IgM may persist for months, presenting a risk of an erroneous diagnosis where serology is the only available tool. Indeed, IgM may be detected in secondary infection as a result of crossreactivity and/or nonspecific stimulation of the immune system. One test that can aid the serologist is IgG avidity testing, in that the avidity of IgG is low early in infection with the avidity of IgG antibodies increasing over time. Congenital toxoplasmosis can induce serious sequelae. Detectable IgM usually persists long after the acute infection. IgG avidity can be an important aid in diagnosis and assessing the risk to the fetus. Another infection that is of concern in pregnancy is cytomegalovirus (CMV). In pregnant women it is very important to differentiate primary from secondary infection, as primary infection presents the highest risk to the fetus. Serologic detection of IgM alone is not a specific marker of primary CMV infection. IgG avidity can have utility in identifying or excluding primary CMV infections during pregnancy. Outside of pregnancy, IgG avidity testing is increasingly recognized as a valuable tool. During the recent West Nile virus (WNV) epidemic in the US, it was recognized that WNV-specific IgM may persist for 6 - 12 months following exposure. Thus, a person presenting to their clinician with nonspecific symptoms may be tested and return a positive WNV IgM that may be the product of exposure during the previous period. In this environment, WNV IgG avidity testing is able to provide some assistance. IgG avidity testing should not be used alone and without an understanding of the limitations of the technique. Serology remains an important tool for the diagnosis and management of infectious disease. Classically, IgM is defined as a marker of acute infection and IgG, in the absence of clinical disease, is often considered a marker of past infection. However, the clinical reality can be quite different.
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Affiliation(s)
- Stuart L Hazell
- Panbio Ltd, 532 Seventeen Mile Rocks Road, Sinnamon Park, Brisbane, Queensland 4073, Australia +617 3363 7100 ; +617 3363 7199 ;
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Evaluation of the new Elecsys Toxo IgG avidity assay for toxoplasmosis and new insights into the interpretation of avidity results. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2012; 19:1838-43. [PMID: 22993406 DOI: 10.1128/cvi.00333-12] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Detection and treatment of acute toxoplasmosis during pregnancy can avoid severe disease of the fetus. In this context, assessment of anti-Toxoplasma IgG avidity has been shown to exclude recent infection. The Elecsys Toxo IgG and IgM assays (Roche Diagnostics) have been validated for screening pregnant women and a new assay, Elecsys Toxo IgG Avidity, was recently developed. Our aims were to investigate the performance characteristics of this new avidity assay and explore whether additional information can be provided by avidity assays. The Elecsys assay was compared with the Vidas (bioMérieux) and Architect (Abbott) Avidity assays using two sets of serum samples (n = 291 and n = 255). The rate of general agreement between the Elecsys and Vidas assays was 74%, and that between the Elecsys and Architect assays was 83%. For 11% of the serum samples, avidity was high with the Vidas assay and within the gray zone with the Elecsys assay. None of the assays detected high-avidity antibodies in serum taken <4 months after infection. Avidity values of >90% were exclusively reported in sera taken >9 months after infection by the Elecsys and Architect assays. Almost all avidities of <19% with the Elecsys assay and <17% with the Architect assay corresponded to sera taken <3 and <2 months after infection, respectively. The Elecsys IgG Avidity assay can be used to exclude recent infection. New ways of interpreting the avidity result are also suggested: very high or low values could exclude infections within the last 9 months or help to confirm a recent infection, respectively. However, these potential interpretations require further investigation.
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Silva-dos-Santos PP, Barros GB, Mineo JR, Silva DADO, Menegaz MHW, Serufo JC, Dietze R, Martins-Filho ODA, Lemos EM. Flow cytometry-based algorithm to analyze the anti-fixed Toxoplasma gondii tachyzoites IgM and IgG reactivity and diagnose human acute toxoplasmosis. J Immunol Methods 2012; 378:33-43. [DOI: 10.1016/j.jim.2012.02.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2011] [Revised: 01/25/2012] [Accepted: 02/01/2012] [Indexed: 11/25/2022]
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Pessanha TM, Carvalho MD, Pone MVS, Gomes Júnior SC. Abordagem diagnóstica e terapêutica da toxoplasmose em gestantes e as repercussões no recém-nascido. REVISTA PAULISTA DE PEDIATRIA 2011. [DOI: 10.1590/s0103-05822011000300006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJETIVO:Avaliar a abordagem diagnóstica e terapêutica da toxoplasmose de gestantes que apresentaram IgM positiva para a doença e o acompanhamento de seus filhos em um hospital público no Rio de Janeiro, RJ. MÉTODOS: Estudo transversal retrospectivo de 2003 a 2006, realizado por meio da análise dos prontuários de 98 gestantes com sorologia IgM positiva para toxoplasmose e seus filhos (99 crianças). O seguimento das crianças com e sem infecção congênita foram analisados, assim como a apresentação clínica daquelas com infecção congênita e os testes diagnósticos utilizados para identificar a infecção pelo Toxoplasma gondii durante a gestação. RESULTADOS: O diagnóstico sorológico foi realizado em 76 pacientes no segundo e terceiro trimestre gestacional. Em 36 gestantes, a determinação dos níveis séricos de IgM foi o único teste diagnóstico realizado para infecção pelo toxoplasma. Em 49 gestantes, os índices de IgM, pela técnica ELFA, foram baixos. O teste de avidez de IgG foi realizado em 62 gestantes e somente 13 o realizaram no primeiro trimestre gestacional. O tratamento específico para toxoplasmose foi empregado em 93 gestantes. A taxa de transmissão vertical foi de 4%. Manifestações clínicas de toxoplasmose congênita foram encontradas em todas as crianças infectadas. Todas as crianças não infectadas apresentaram declínio de IgG específica para toxoplasmose ao longo do acompanhamento ambulatorial; a idade média de IgG comprovadamente negativa nessas crianças foi de 5,4 meses. CONCLUSÕES: Os resultados sugerem que uma sorologia positiva para IgM, como um único marcador sorológico para detectar infecção recente, tem um valor limitado.
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Use of dense granule antigen GRA6 in an immunoglobulin G avidity test to exclude acute Toxoplasma gondii infection during pregnancy. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2010; 17:1349-55. [PMID: 20631335 DOI: 10.1128/cvi.00199-10] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The usefulness of a specific immunoglobulin G (IgG) avidity enzyme-linked immunosorbent assay (ELISA) based on recombinant GRA6 antigen for distinguishing between acute and chronic Toxoplasma infection was investigated. Two sets of serum samples obtained from pregnant women with acute, chronic, or no Toxoplasma infection collected in France and Iran were used. Among the French subjects, 19 of 20 (95%) women who experienced seroconversion during the past 4 months before sampling displayed low-avidity IgG antibodies against GRA6, while all 17 (100%) women with chronic infection had high-avidity antibodies. When the Euroimmun IgG avidity ELISA was used, 15 of 19 (78.9%) recently infected women had low-avidity antibodies, and 20 of 22 (90.9%) women with chronic infection displayed high-avidity antibodies. The results suggested better performance of the GRA6 avidity ELISA than the Euroimmun avidity ELISA for exclusion of a recent infection occurring less than 4 months previously. Similarly, all 35 Iranian women with acute Toxoplasma infection had low-avidity antibodies against GRA6, whereas all 34 women with chronic infection displayed IgG antibodies of high avidity, indicating the value of GRA6 avidity testing for ruling out a recent infection. Avidity tests based on lysed whole-cell Toxoplasma gondii antigen are currently used to exclude recently acquired infections; however, the use of recombinant antigen(s) might improve the diagnostic performance of avidity tests and facilitate the development of more standardized assays.
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Macre MDS, Pires M, Meireles LR, Angel SO, Andrade HFD. Serology using rROP2 antigen in the diagnostic of toxoplasmosis in pregnant women. Rev Inst Med Trop Sao Paulo 2010; 51:283-8. [PMID: 19893982 DOI: 10.1590/s0036-46652009000500009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2009] [Accepted: 07/14/2009] [Indexed: 11/21/2022] Open
Abstract
Toxoplasma gondii causes severe fetal disease during acute infection in pregnant women, thus demanding early diagnosis for effective treatment and fetus preservation. Fetal tests are inefficient and risky, and diagnosis is based on maternal IgM serology, which had weak screening ability due to increased sensitivity, with alternative IgG avidity tests. Here, we performed ELISA and avidity assays using a recombinant T. gondii antigen, rROP2, in samples from 160 pregnant women screened from a large public hospital who were referred due to positive IgM assays. IgG serology and avidity assays were compared using whole T. gondii extract or rROP2. ELISA IgG detection with rROP2 showed good agreement with assays performed with T. gondii extract, but rROP2 IgG avidity assays were unrelated to whole extract antigen IgG avidity, regardless of the chaotrope used. These data show that avidity maturation is specific to individual antigen prevalence and immune response during infection. ELISA rROP2 IgG assays may be an alternative serological test for the diagnosis of toxoplasmosis during pregnancy, although our data do not support their use in avidity assays.
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Affiliation(s)
- Miriam de Souza Macre
- Laboratório de Protozoologia, Instituto de Medicina Tropical de São Paulo, USP, São Paulo, SP, Brasil, 05403-000
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Spiramycin treatment of Toxoplasma gondii infection in pregnant women impairs the production and the avidity maturation of T. gondii-specific immunoglobulin G antibodies. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2009; 16:1517-20. [PMID: 19692628 DOI: 10.1128/cvi.00253-09] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The aim of the study was to evaluate the influence of treatment with spiramycin on the increase of immunoglobulin G (IgG) titers and IgG avidity indexes (AI) in pregnant women with seroconversion from the beginning of therapy until delivery and after delivery. This group was compared with adult patients with recently acquired untreated toxoplasmosis. One hundred four samples from 32 pregnant women with seroconversion for toxoplasmosis and/or very low IgG AI were followed from the beginning of therapy with spiramycin until delivery. Twenty-nine women were further followed some months after delivery and interruption of therapy. Thirty-eight samples from 16 untreated, nonpregnant patients were evaluated as the control group. The Toxoplasma gondii-specific IgG antibody and the T. gondii-specific IgG AI were significantly delayed in pregnant women receiving therapy compared to nonpregnant, untreated controls, and the findings were consistent with the results of assays from two different manufacturers. The T. gondii-specific IgG AI increased in pregnant women after they gave birth. Avidity maturation is delayed during pregnancy and treatment, and low-avidity antibodies in pregnant women within 3 to 4 months cannot be taken as a sign of infection.
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Lachaud L, Calas O, Picot MC, Albaba S, Bourgeois N, Pratlong F. Value of 2 IgG avidity commercial tests used alone or in association to date toxoplasmosis contamination. Diagn Microbiol Infect Dis 2009; 64:267-74. [PMID: 19395217 DOI: 10.1016/j.diagmicrobio.2009.02.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Revised: 02/20/2009] [Accepted: 02/25/2009] [Indexed: 11/16/2022]
Abstract
Toxoplasmosis acquired during pregnancy exposes the fetus to congenital toxoplasmosis. Avidity tests are commonly used to date time of infection to evaluate the fetal risk and to offer prenatal diagnosis. This study evaluated and compared 2 commercial avidity tests: Platelia Toxo IgG Avidity (Bio-Rad, Marnes la Coquette, France) and Liaison(R) Toxo IgG Avidity II (Diasorin, Saluggia, Italy) kits. In complement, a study of specific IgG and IgM in the 2 systems was carried out. Sensitivity and specificity of the avidity tests were 94.4% and 87.8% for the Liaison(R) and 91.3% and 98.5% for the Platelia methods, respectively. Percentages of complete discrepancies, partial discrepancies, and agreement between both tests were 1.1%, 23.6%, and 75.3%, respectively. Moreover, the combination of both avidity tests may be useful in some cases. Indeed, that strategy permitted to confirm without delay a chronic toxoplasmosis in 23 cases and avoid treatment in these pregnant women.
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Affiliation(s)
- Laurence Lachaud
- Université Montpellier I, Centre Hospitalier Universitaire, Nîmes, France.
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34
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Montoya JG, Remington JS. Management of Toxoplasma gondii infection during pregnancy. Clin Infect Dis 2008; 47:554-66. [PMID: 18624630 DOI: 10.1086/590149] [Citation(s) in RCA: 365] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Acute infection with Toxoplasma gondii during pregnancy and its potentially tragic outcome for the fetus and newborn continue to occur in the United States, as well as worldwide, despite the fact that it can be prevented. The infection can be acquired through ingestion of infected, undercooked meat or contaminated food or water. Transmission to the fetus occurs almost solely in women who acquire their primary infection during gestation and can result in visual and hearing loss, mental and psychomotor retardation, seizures, hematological abnormalities, hepatosplenomegaly, or death. Systematic education and serological screening of pregnant women are the most reliable and currently available strategies for the prevention, diagnosis, and early treatment of the infection in the offspring; this is largely because toxoplasmosis in pregnant women most often goes unrecognized. Treatment of the infection in the fetus and infant during the first year of life has been demonstrated to significantly improve the clinical outcome.
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Affiliation(s)
- Jose G Montoya
- Palo Alto Medical Foundation Toxoplasma Serology Laboratory, Palo Alto, California, USA
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35
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Flori P, Bellete B, Crampe C, Maudry A, Patural H, Chauleur C, Hafid J, Raberin H, Sung RTM. A technique for dating toxoplasmosis in pregnancy and comparison with the Vidas anti-toxoplasma IgG avidity test. Clin Microbiol Infect 2008; 14:242-9. [DOI: 10.1111/j.1469-0691.2007.01905.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Assi MA, Rosenblatt JE, Marshall WF. Donor-transmitted toxoplasmosis in liver transplant recipients: a case report and literature review. Transpl Infect Dis 2007; 9:132-6. [PMID: 17461999 DOI: 10.1111/j.1399-3062.2006.00187.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Transmission of toxoplasmosis via liver transplantation is extremely uncommon. Here we report the case of a 52-year-old male liver transplant recipient who on day 32 post transplant developed pneumonia followed by respiratory failure. Donor-transmitted toxoplasmosis was confirmed as the etiology by both serologic and molecular testing. We also review all previously published cases of toxoplasmosis in the English-language adult liver transplant literature.
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Affiliation(s)
- M A Assi
- Division of Infectious Diseases, Department of Internal Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA
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37
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Lefevre-Pettazzoni M, Le Cam S, Wallon M, Peyron F. Delayed maturation of immunoglobulin G avidity: implication for the diagnosis of toxoplasmosis in pregnant women. Eur J Clin Microbiol Infect Dis 2006; 25:687-93. [PMID: 17024503 DOI: 10.1007/s10096-006-0204-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The low avidity of immunoglobulin G has been reported to be a useful marker of recent infection with Toxoplasma. Several investigators, however, have published discrepant result on the maturation of avidity over time. The aim of this study was to analyse persistent low avidity of immunoglobulin G in immunocompetent individuals and in pregnant women and how it could interfere in the flowchart of antenatal diagnosis of toxoplasmosis in the latter group. An international literature search was conducted together with a retrospective study of a hospital database. Eleven publications that met the inclusion criteria reported delayed maturation of avidity at a frequency ranging from 0 to 66.6% of the patients. Examination of those publications demonstrated an important heterogeneity in the type of assay used, the calculation of avidity, the cutoff above which avidity was considered to be elevated, and the delay since infection after which indices are expected to be high. In the hospital database, persistent low avidity was found even after a median follow-up period of 6 years. Different factors could interfere with maturation of avidity, such as variations between individuals, the assay system used, and, possibly, the treatment administered. The results of this study clearly demonstrate that, in a pregnant woman, an acute infection cannot be reliably diagnosed solely on the basis of low avidity of immunoglobulin G. Further investigations and standardization of assays are urgently needed. Estimation of the time of infection remains difficult, especially in cases in which the samples are drawn late in pregnancy; the final estimate must be based on several tests repeated at intervals of weeks.
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Affiliation(s)
- M Lefevre-Pettazzoni
- Département de Parasitologie, Hôpital de la Croix Rousse, 69317, Lyon Cedex 04, France
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Pietkiewicz H, Hiszczyńska-Sawicka E, Kur J, Petersen E, Nielsen HV, Paul M, Stankiewicz M, Myjak P. Usefulness of Toxoplasma gondii recombinant antigens (GRA1, GRA7 and SAG1) in an immunoglobulin G avidity test for the serodiagnosis of toxoplasmosis. Parasitol Res 2006; 100:333-7. [PMID: 16896649 DOI: 10.1007/s00436-006-0265-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2006] [Accepted: 06/02/2006] [Indexed: 10/24/2022]
Abstract
The precise diagnosis of an acute and recent Toxoplasma infection in pregnant women and the newborn child is important before treatment. This study describes a new Toxoplasma gondii IgG avidity test based on a combination of recombinant GRA1, GRA7 and SAG1 antigens and shows that this test is useful for diagnostic purposes and may replace the lysed, whole-cell antigens. Although more sera need to be tested, the results obtained here suggest that the IgG avidity test performed with rec-antigens correlated more with the stage of a T. gondii infection than the IgG avidity results obtained with the lysed, whole-cell antigen test, the VIDAS Toxo IgG avidity (bioMérieux).
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Affiliation(s)
- H Pietkiewicz
- Department of Tropical Parasitology, Inter-Faculty Institute of Maritime and Tropical Medicine, Medical University of Gdańsk, ul. Powstania Styczniowego 9b, Gdynia, Poland
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Fricker-Hidalgo H, Saddoux C, Suchel-Jambon AS, Romand S, Foussadier A, Pelloux H, Thulliez P. New Vidas assay for Toxoplasma-specific IgG avidity: evaluation on 603 sera. Diagn Microbiol Infect Dis 2006; 56:167-72. [PMID: 16725296 DOI: 10.1016/j.diagmicrobio.2006.04.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2005] [Revised: 03/27/2006] [Accepted: 04/07/2006] [Indexed: 10/24/2022]
Abstract
After the development of the new version of the test Vidas Toxo IgG with antigens obtained from tachyzoites cultured on cells, a Vidas avidity test has been recently developed. The aim of this study was to assess the value of the determination of avidity on the new Vidas test. This avidity test was performed on 553 sera obtained from pregnant women whose dates of infection had been determined and on 50 sera obtained from immunosuppressed patients. In the group of infection occurring less than 4 months before sampling, the avidity index was <0.3 on 266 among 267 sera. In the group of infection occurring more than 15 months before sampling, the avidity index was >0.3 for 44/46 sera of pregnant women and for 47/47 sera of immunosuppressed patients. Thus, the new version of avidity test was helpful primarily to rule out that an infection had occurred within the prior 4 months.
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Affiliation(s)
- Hélène Fricker-Hidalgo
- Service de Parasitologie-Mycologie, Centre Hospitalier Universitaire de Grenoble, BP217, 38043 Grenoble Cedex 9, France.
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Petersen E, Borobio MV, Guy E, Liesenfeld O, Meroni V, Naessens A, Spranzi E, Thulliez P. European multicenter study of the LIAISON automated diagnostic system for determination of Toxoplasma gondii-specific immunoglobulin G (IgG) and IgM and the IgG avidity index. J Clin Microbiol 2005; 43:1570-4. [PMID: 15814967 PMCID: PMC1081322 DOI: 10.1128/jcm.43.4.1570-1574.2005] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The LIAISON system is a fully automated system based on chemiluminescence and antigen bound to magnetic microparticles. The system allows fast and precise measurement of Toxoplasma-specific immunoglobulin G (IgG) and IgM antibody levels and measurement of the IgG avidity index even at low levels of Toxoplasma-specific IgG antibodies in a single step without manual interference. Seven European centers participated in a multicenter evaluation of the LIAISON system. The sensitivity and specificity of the LIAISON system compared to the Sabin-Feldman dye test were 99.3 and 96.8%, respectively. In a comparison of the LIAISON Toxoplasma-specific IgM assay with an immunosorbent agglutination assay, the LIAISON assay had a sensitivity of 96.7% and a specificity of 95.4%. The LIAISON IgG assay showed agreements of 91, 100, and 100% with the AXSYM IgG (Abbott), VIDAS IgG (bioMerieux), and Platelia IgG (Bio-Rad) assays, respectively. The LIAISON IgM assay showed agreements of 95% with the AXSYM IgM and Platelia IgM assays, 96% with the ISAGA IgM assay (bioMerieux), and 97% with the VIDAS IgM assay. The coefficient of correlation between the LIAISON system and the VIDAS Toxoplasma-specific IgG avidity index was 0.81. By use of the Toxoplasma-specific IgG avidity index assay with specific IgM-positive samples, the diagnosis of infection with Toxoplasma gondii in early pregnancy has been improved significantly. The LIAISON avidity assay is a valuable assay for the exclusion of recently acquired infection with T. gondii (less than 4 months) in pregnant women, and it decreases significantly the necessity for follow-up testing.
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Affiliation(s)
- Eskild Petersen
- WHO/FAO International Centre for Research and Reference on Toxoplasmosis, Statens Serum Institut, Artillerivej 5, DK-2300 Copenhagen S, Denmark.
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Kaul R, Chen P, Binder SR. Detection of immunoglobulin M antibodies specific for Toxoplasma gondii with increased selectivity for recently acquired infections. J Clin Microbiol 2005; 42:5705-9. [PMID: 15583302 PMCID: PMC535241 DOI: 10.1128/jcm.42.12.5705-5709.2004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Toxoplasma gondii infections can cause serious complications in pregnant women, leading to miscarriage, stillbirth, and birth defects. Definitive diagnosis of T. gondii acute infection is therefore critical for the clinical management of a mother and her fetus. Positive immunoglobulin M (IgM) results are not sufficient as evidence of recent infection, as these antibodies are often present for many months. Further, IgG avidity and differential agglutination tests, two tests used by reference laboratories to distinguish between recent and past infections, are not always in agreement, and both methods yield a significant number of indeterminate results. We report the development of a new toxoplasma IgM immunoassay that is performed by using a bead-based immunoassay on an automated analyzer (BioPlex 2200). Initial validation included 204 samples from pregnant women and 198 samples from asymptomatic healthy adults. An overall specificity of 99% was observed. Further, 100% sensitivity for acute infections was observed for 10 well-characterized seroconversion panels. We then examined 50 samples from pregnant women, all of which were IgM positive by ELISA, which had been fully evaluated in a reference laboratory. Of the 50 samples, 34 (68%) tested positive in the BioPlex 2200 toxoplasma IgM assay, of which 32 of 34 (94%) exhibited an acute or equivocal pattern by differential agglutination. Of the 16 negative samples, 15 (94%) showed high-IgG-avidity antibodies. Collectively, these results suggest that this new toxoplasma assay shows a preferential response to IgM antibodies produced by recent infections, reducing the number of positive results for pregnant women that will require extensive additional clinical evaluation.
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Affiliation(s)
- Ravi Kaul
- Clinical Diagnostic Group, Bio-Rad Laboratories, 4000 Alfred Nobel Dr., Hercules, CA 94547, USA.
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Flori P, Tardy L, Patural H, Bellete B, Varlet MN, Hafid J, Raberin H, Sung RTM. Reliability of immunoglobulin G antitoxoplasma avidity test and effects of treatment on avidity indexes of infants and pregnant women. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2005; 11:669-74. [PMID: 15242939 PMCID: PMC440619 DOI: 10.1128/cdli.11.4.669-674.2004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The immunoglobulin G antitoxoplasma avidity test (Vidas; BioMérieux) is an immunoenzymatic test useful for excluding acute infection after the onset of pregnancy. The avidity index (AI) is the ratio of the signal in a test sample washed with urea, which disrupts low-avidity complexes, to that washed without urea. An AI of >0.3 is taken to mean that infection had occurred more than 4 months ago. The increase of the AI with time and the influence of the different treatments given to pregnant women and their newborns were evaluated. A total of 59 pregnant women (271 sera) and their 60 neonates (199 sera) were tested from 1998 to 2002. There were five groups of women based on the type and duration of treatment given. Thirteen pregnant women (group 1) did not receive any treatment, 15 (group 2), 11 (group 3), and 17 (group 4) women received treatment with spiramycin (9 MIU/day) for 0.5 to 2, 2.5 to 5, and 5.5 to 8 months, respectively, and the last 3 women (group 5) received tritherapy (pyrimethamine-sulfonamide and spiramycin alternatively) for 1.5 to 2.5 months. All of the maternal sera collected in the first 6 months had an AI of <0.30, with a mean of 0.07 (range, 0.01 to 0.21). The increase was slow (0.02/month), and there was no significant difference when comparisons were made between the treatment groups. Neonates with proven maternofetal transmission had an increasing AI, unlike those without transmission. However, long-term therapy with pyrimethamine-sulfonamide, as opposed to treatment with spiramycin alone, was found to slow down the progression of the AI. An AI of >0.2 is sufficient to exclude acute infection in pregnant women. In neonates, it is not of major use to diagnose congenital infection; however, it could be a good indicator of compliance and efficacy of treatment of infected infants.
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Affiliation(s)
- Pierre Flori
- Laboratory of Parasitology and Mycology, Hôpital Nord, University Hospital of Saint Etienne, France.
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43
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Montoya JG, Huffman HB, Remington JS. Evaluation of the immunoglobulin G avidity test for diagnosis of toxoplasmic lymphadenopathy. J Clin Microbiol 2004; 42:4627-31. [PMID: 15472320 PMCID: PMC522337 DOI: 10.1128/jcm.42.10.4627-4631.2004] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Toxoplasmic lymphadenopathy (TL) is the most common clinical manifestation of acute acquired toxoplasma infection in normal individuals. The diagnosis is established by serologic methods and lymph node biopsy. Recently, tests for avidity of toxoplasma immunoglobulin G (IgG) antibodies have been introduced to help discriminate between recently acquired and distant infection with the parasite. We studied an avidity test to define the usefulness of this method and to determine the evolution of the IgG avidity in TL. Seventy-three consecutive patients diagnosed as having TL were studied. IgG avidity test titers were noted to be time dependent from the clinical onset of lymphadenopathy. Low IgG avidity test results were observed in patients who had developed lymphadenopathy from <1 month to 17 months prior to the sampling of sera, emphasizing that low IgG avidity test results are not reliable for diagnosis of recently acquired infection. In contrast, high IgG avidity test results were observed only in patients who had developed lymphadenopathy at least 4 months earlier. Thus, a high IgG avidity test result in an individual who has recent onset of lymphadenopathy (e.g., within 2 to 3 months of sera sampling) suggests a cause other than toxoplasmosis. In such cases, further workup is warranted in order to determine the cause of the lymphadenopathy.
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Affiliation(s)
- Jose G Montoya
- Department of Immunology and Infectious Diseases, Research Institute, Palo Alto Medical Foundation, Palo Alto, California 94301, USA.
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44
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Buffolano W, Lappalainen M, Hedman L, Ciccimarra F, Del Pezzo M, Rescaldani R, Gargano N, Hedman K. Delayed maturation of IgG avidity in congenital toxoplasmosis. Eur J Clin Microbiol Infect Dis 2004; 23:825-30. [PMID: 15558340 DOI: 10.1007/s10096-004-1226-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The aim of this comparative study was to investigate the clinical usefulness of the measurement of Toxoplasma gondii IgG avidity in the postnatal diagnosis of congenital toxoplasmosis. IgG avidity values in serum samples from infants with congenital infection were compared with those in samples from uninfected infants, all born to mothers with toxoplasmosis acquired during gestation. This analysis revealed that IgG avidity values soon after birth reflected maternal values in the large majority of the samples. Low or borderline IgG avidity values were systematically found in the cohort of congenitally infected subjects. After birth, IgG avidity values slowly increased over time for up to 2 years in congenitally infected subjects. On the contrary, IgG avidity values in the uninfected infants remained stable over time. The presence of low IgG avidity in a newborn can be considered a marker of maternal seroconversion in the second or third trimester of gestation and, as a consequence, an indicator of risk for congenital toxoplasmosis. An IgG avidity assay can be easily carried out with antibodies eluted from dried blood spots (Guthrie cards), providing an opportunity to retrospectively evaluate the risk of congenital infection in special clinical circumstances, for example when suspicion of congenital infection arises during late infancy.
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Affiliation(s)
- W Buffolano
- Pediatrics Department, Federico II Naples University, via Pansini 5, 80131 Naples, Italy.
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Singh S, Pandit AJ. Incidence and prevalence of toxoplasmosis in Indian pregnant women: a prospective study. Am J Reprod Immunol 2004; 52:276-83. [PMID: 15494049 DOI: 10.1111/j.1600-0897.2004.00222.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
PROBLEM Toxoplasmosis is a major cause of congenitally acquired infections causing high degree of morbidity and mortality in the newborns. METHODS OF STUDY IgG avidity method was used to distinguish the recent and more than 4 months old infection in a prospective cohort study for the first time in India. One hundred and eighty pregnant women presented in their first 4 months of pregnancy were included in this study. Their sera were tested for anti-Toxoplasma gondii antibodies using direct agglutination test, immunoglobulin (Ig)G and IgM-enzyme-linked immunosorbent assay, IgM-immunosorbent agglutination assay and VIDAS-IgG avidity. RESULTS Overall IgG seroprevalence rate of toxoplasmosis was 45%. Only seven women (3.3%) were found to have IgM antibodies and only two of these showed low IgG avidity indicating recent infection of <or=4 months duration. One woman aborted spontaneously at her fourth month of gestation. In remaining five women the recent infection could successfully be excluded by IgG avidity testing. All these women had uneventful pregnancy. CONCLUSIONS This study indicated that all IgM antibody positive pregnant must be tested for IgG avidity to rule out recent primary infection.
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Affiliation(s)
- Sarman Singh
- Division of Clinical Microbiology, All India Institute of Medical Sciences, New Delhi, India.
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Beghetto E, Buffolano W, Spadoni A, Del Pezzo M, Di Cristina M, Minenkova O, Petersen E, Felici F, Gargano N. Use of an immunoglobulin G avidity assay based on recombinant antigens for diagnosis of primary Toxoplasma gondii infection during pregnancy. J Clin Microbiol 2004; 41:5414-8. [PMID: 14662919 PMCID: PMC308957 DOI: 10.1128/jcm.41.12.5414-5418.2003] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The objective of this work was to develop an antibody-specific immunoglobulin G (IgG) avidity assay to discriminate between acute and latent phases of Toxoplasma gondii infection by using recombinant antigens. One hundred twenty-one serum samples from women who developed IgG antibodies against Toxoplasma during pregnancy were used. The IgG avidities of antibodies directed against epitopes carried by fragments of GRA3, GRA7, MIC3, and SAG1 antigens were measured by performing parallel enzyme immunoassays. The avidity index for Toxoplasma-specific antibodies against a homogeneous mixture of recombinant GRA3, GRA7, MIC3, and SAG1 antigens correlated closely with the IgG avidity of antibodies against lysed whole-cell T. gondii antigen. The avidity assay performed with the recombinant MIC3 antigen highlighted the presence of avidity low-antibodies IgG exclusively in sera collected within 2 months after primary infection. The presence of T. gondii-specific, low-avidity IgG antibodies against recombinant MIC3 antigen can be used to determine the point of infection with T. gondii within a 2-month time frame after infection.
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Affiliation(s)
- Elisa Beghetto
- Kenton Laboratories, Rome, Federico II University, Naples, Italy
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Nigro M, Gutierrez A, Hoffer AM, Clemente M, Kaufer F, Carral L, Martin V, Guarnera EA, Angel SO. Evaluation of Toxoplasma gondii recombinant proteins for the diagnosis of recently acquired toxoplasmosis by an immunoglobulin G analysis. Diagn Microbiol Infect Dis 2004; 47:609-13. [PMID: 14711483 DOI: 10.1016/s0732-8893(03)00156-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The value of T. gondii recombinant antigens rRop2, rGra4, rGra7 and rSAG1m (mature version) or rSAG1ct (C-terminal version) in differentiating recently acquired from chronic infections was determined by IgG-ELISA. The general highest sensitivity was observed with rRop2 whereas rSAG1m was not recognized by any of the serum samples, suggesting an incorrect folding. rGra4 and rGra7 showed significant higher sensitivity and absorbance values with serum samples from recently infected individuals compared to those with chronic infection. In contrast, rRop2 and rSAG1ct did not show differences in the reactivity pattern between both groups of serum samples.
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Affiliation(s)
- Monica Nigro
- Departamento de Parasitología, ANLIS Dr. Carlos G. Malbran, Av. Velez Sarsfield 563, 1281-Ciudad Autónoma de, Buenos Aires, Argentina
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Robert-Gangneux F, Binisti P, Antonetti D, Brezin A, Yera H, Dupouy-Camet J. Usefulness of immunoblotting and Goldmann-Witmer coefficient for biological diagnosis of toxoplasmic retinochoroiditis. Eur J Clin Microbiol Infect Dis 2003; 23:34-8. [PMID: 14669070 DOI: 10.1007/s10096-003-1048-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Toxoplasmosis is a frequent cause of retinochoroiditis. Although the diagnosis relies mainly on ophthalmological examination, biological approaches are particularly useful in patients with atypical lesions. In a prospective study to determine the value of immunoblotting and immune load calculation in the diagnosis of active toxoplasmic retinochoroiditis, aqueous humor samples from 21 patients with retinochoroiditis and 5 control patients with cataracts were tested. Immune load was calculated on the basis of intraocular antibody production. The immune load ratio between aqueous humor and serum (Goldmann-Witmer coefficient) was significant (i.e. >2) in 9 of the 17 (53%) patients with retrospectively documented toxoplasmic retinochoroiditis. Immunoblotting suggested local antibody production in 10 of 17 (59%) patients. The combination of the two techniques gave a sensitivity of 71% (12/17). Both techniques were negative in the four patients in whom the final diagnosis of toxoplasmic retinochoroiditis was negative and in the five patients with cataracts. These results confirm the value of combining these two techniques. Moreover, immunoblotting has the advantages of being easy to perform and of requiring a very small sample.
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Affiliation(s)
- F Robert-Gangneux
- Laboratory of Parasitology and Mycology, University of Medicine Paris 5, Hospital Cochin-Port Royal, 27 rue du Faubourg Saint-Jacques, 75014 Paris, France.
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MOTHER-TO-CHILD TRANSMISSION AND DIAGNOSIS OF TOXOPLASMA GONDII INFECTION DURING PREGNANCY. Indian J Med Microbiol 2003. [DOI: 10.1016/s0255-0857(21)03124-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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50
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Pelloux H, Brenier-Pinchart MP, Fricker-Hidalgo H. Protozoan infections in humans: congenital toxoplasmosis. Eur J Protistol 2003. [DOI: 10.1078/0932-4739-00018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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