Comparison of four serological assays for the diagnosis of Chlamydia trachomatis in subfertile women

Introduction: Chlamydia antibody testing (CAT) in serum has been introduced as a screening method in the infertility workup. We evaluated the test characteristics of two ELISA tests compared to micro-immunofluorescence tests (MIFs). MIFs are considered the gold standard in the C. trachomatis IgG antibodies detection. We also compared the accuracy of all CAT tests in predicting tubal subfertility, using laparoscopy as a reference. Methodology: Four commercial serological methods were used to analyse 101 serum samples for the presence of C. trachomatis IgG antibodies from patients at the Infertility Clinic of Ghent University Hospital. The diagnostic utility for prediction of tubal infertility of serological methods was evaluated based on patients' medical records. Results: A comparison of the serological assays showed little difference in the major performance characteristics: the sensitivities of all MIFs and ELISAs were 100% for all assays (except the ELISA Vircell, with a sensitivity of 90%), and the specificities ranged from 92% for MIF Ani Labsystems to 98% for the MIF Focus and ELISA Vircell. As compared to laparoscopy data, CAT positivity in subfertile women with tubal damage (n=40) did not significantly differ from that of subfertile women without tubal damage (n=61): Positive predictive values (PPV) of CAT ranged from 53% to 60% and negative predictive values (NPV) ranged from 62% to 64%. Conclusion: evaluated ELISAs are comparable to MIFs in the detection of C. trachomatis IgG antibodies and should be preferred for large serological studies, especially in resource poor settings.

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Evaluation of anti-SARS-CoV-2 antibody testing in asymptomatic or mild COVID-19 patients in outbreak on a cruise ship

10.1101/2021.03.10.21253064 ◽

2021 ◽

Author(s):

Norihito Kaku ◽

Fumitaka Nishimura ◽

Yui Shigeishi ◽

Rina Tachiki ◽

Hironori Sakai ◽

...

Keyword(s):

Genetic Test ◽

False Negative ◽

Enzyme Linked Immunosorbent Assay ◽

Cruise Ship ◽

Igg Antibodies ◽

Antibody Testing ◽

Predictive Values ◽

Blood Samples ◽

Negative Results ◽

Genetic Test Results

AbstractBackgroundA few studies on antibody testing have focused on asymptomatic or mild coronavirus disease 2019 (COVID-19) patients with low initial anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody responses. Anti-SARS-CoV-2 antibody-testing performance was evaluated using blood samples from asymptomatic or mild COVID-19 patients.MethodsBlood samples were collected from 143 COVID-19 patients during an outbreak on a cruise ship 3 weeks after diagnosis. Simultaneously, a second SARS-CoV-2 genetic test was performed. Samples stored before the COVID-19 pandemic were also used to evaluate the lateral flow immunochromatographic assay (LFA) and electrochemiluminescence immunoassay (ECLIA). Titers of anti-SARS-CoV-2 IgM and IgG antibodies against the nucleocapsid and spike proteins were measured using the enzyme-linked immunosorbent assay to compare false-negative- with positive-result samples.ResultsSensitivity, specificity, positive-predictive, and negative-predictive values of LFA-detected IgM antibodies were 0.231, 1.000, 1.000, and 0.613, respectively; those of LFA-detected IgG antibodies were 0.483, 0.989, 0.972, and 0.601, respectively; and those of ECLIA-detected total antibodies were 0.783, 1.000, 1.000, and 0.848, respectively. IgM-, IgG-, and total-antibody positivity rates in the patients with negative results from the second genetic testing were 22.9%, 47.6%, and 72.4%, respectively. All antibody titers, especially those of the IgG antibody against nucleocapsid protein, were significantly lower in blood samples with false-negative results than in those with positive results.ConclusionsThese findings suggest that anti-SARS-CoV-2 antibody testing has lower performance in asymptomatic or mild COVID-19 patients than required in the guidelines, and situations in which it is useful are limited.Key pointsAnti-SARS-CoV-2 antibody testing in asymptomatic or mild COVID-19 patients is lower than the required clinical sensitivity, although it may be useful in patients at 3–4 weeks after symptom onset but with negative SARS-CoV-2 genetic test results.

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Joint Detection of Serum IgM/IgG Antibody Is an Important Key to Clinical Diagnosis of SARS-CoV-2 Infection

Canadian Journal of Infectious Diseases and Medical Microbiology ◽

10.1155/2020/1020843 ◽

2020 ◽

Vol 2020 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

Fang Hu ◽

Xiaoling Shang ◽

Meizhou Chen ◽

Changliang Zhang

Keyword(s):

Screening Tool ◽

Control Group ◽

Joint Detection ◽

Igg Antibodies ◽

Antibody Testing ◽

Serum Samples ◽

Igg Antibody ◽

Important Diagnostic Tool ◽

Acid Test ◽

Combined Detection

Background. This study was aimed to investigate the application of SARS-CoV-2 IgM and IgG antibodies in diagnosis of COVID-19 infection. Method. This study enrolled a total of 178 patients at Huangshi Central Hospital from January to February 2020. Among them, 68 patients were SARS-CoV-2 infected, confirmed with nucleic acid test (NAT) and CT imaging. Nine patients were in the suspected group (NAT negative) with fever and other respiratory symptoms. 101 patients were in the control group with other diseases and negative to SARS-CoV-2 infection. After serum samples were collected, SARS-CoV-2 IgG and IgM antibodies were tested by chemiluminescence immunoassay (CLIA) for all patients. Results. The specificity of serum IgM and IgG antibodies to SARS-CoV-2 was 99.01% (100/101) and 96.04% (97/101), respectively, and the sensitivity was 88.24% (60/68) and 97.06% (66/68), respectively. The combined detection rate of SARS-CoV-2 IgM and IgG antibodies was 98.53% (67/68). Conclusion. Combined detection of serum SARS-CoV-2 IgM and IgG antibodies had better sensitivity compared with single IgM or IgG antibody testing, which can be used as an important diagnostic tool for SARS-CoV-2 infection and a screening tool of potential SARS-CoV-2 carriers in clinics, hospitals, and accredited scientific laboratories.

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The diagnostic utility of serum IgG4 concentrations in IgG4-related disease

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2013-204907 ◽

2014 ◽

Vol 74 (1) ◽

pp. 14-18 ◽

Cited By ~ 223

Author(s):

Mollie N Carruthers ◽

Arezou Khosroshahi ◽

Tamara Augustin ◽

Vikram Deshpande ◽

John H Stone

Keyword(s):

Positive Predictive Value ◽

Electronic Medical Records ◽

Predictive Value ◽

Medical Records ◽

Elevated Serum ◽

Predictive Values ◽

Test Characteristics ◽

Igg4 Related Disease ◽

Serum Igg4 ◽

Sensitivity Specificity

ObjectivesWe evaluated the sensitivity, specificity and positive and negative predictive values of elevated serum IgG4 concentrations for the diagnosis of IgG4-RD.MethodsBetween 2001 and 2011, 190 unique patients had elevated serum IgG4 measurements. We reviewed electronic medical records to determine the indication for IgG4 measurement and underlying clinical diagnosis. Additionally, we reviewed the records of 190 other randomly selected patients from a pool of 3360 with normal results, to evaluate test characteristics of the IgG4 measurement.ResultsAmong 380 patients analysed, 72 had either probable or definite IgG4-RD. Sixty-five of the 72 IgG4-RD patients had elevated serum IgG4 concentrations (mean: 405 mg/dL; range 140–2000 mg/dL), for a sensitivity of 90%. Among the 308 subjects without IgG4-RD, 125 had elevated IgG4 (mean: 234 mg/dL; range 135–1180 mg/dL) and 183 had normal IgG4 concentrations, for a specificity of 60%. The negative predictive value of a serum IgG4 assay was 96%, but the positive predictive value only 34%. Analysis of the serum IgG4/total IgG ratio did not improve these test characteristics. Doubling the cutoff for IgG4 improved specificity (91%) but decreased sensitivity to 35%.DiscussionMultiple non-IgG4-RD conditions are associated with elevated serum IgG4, leading to poor specificity and low positive predictive value for this test. A substantial subset of patients with biopsy-proven IgG4-RD do not have elevated serum IgG4. Neither doubling the cutoff for serum IgG4 nor examining the serum IgG4/IgG ratio improves the overall test characteristics for the diagnosis of IgG4-RD.

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Increasing incidence of non-HBV- and non-HCV-related hepatocellular carcinoma: single-institution 20-year study

BMC Gastroenterology ◽

10.1186/s12876-021-01884-5 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Yuko Nagaoki ◽

Hideyuki Hyogo ◽

Yuwa Ando ◽

Yumi Kosaka ◽

Shinsuke Uchikawa ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Medical Records ◽

Screening Method ◽

The Other ◽

University Hospital ◽

Single Institution ◽

Regional University ◽

Cryptogenic Hepatitis ◽

Malignant Liver

Abstract Background We previously reported on the trends in the etiologies of hepatocellular carcinoma (HCC) diagnosed in patients between 1995 and 2009. The aims of our updated study were to evaluate the incidence, nonhepatitis B and nonhepatitis C viral (NBNC) etiologies, and clinical characteristics of HCCs occurring in patients between 1992 and 2018. Methods The study enrolled 2171 consecutive patients with HCC between 1992 and 2018. Their medical records were reviewed. The patients were divided into two groups, patients with early diagnoses from 1992 to 2009 and those with late diagnoses from 2010 to 2018. Results NBNC-HCC occurred in 514 patients (23.6%). The percentage of patients with HCC who had NBNC-HCC increased from 26.5% in 2009 to 46.3% in 2018. Patients with NBNC-HCC were older (median ages from 67 to 73 years). Type 2 diabetes mellitus (48.5–60.3%: P = 0.008), hypertension (48.5–57.4%: P = 0.047), and hyperlipidemia (39.2–53.8%: P = 0.001) increased significantly in recent years. The median FIB-4 index decreased (4.37–3.61: P = 0.026) and the median platelet count increased (15.1–17.9 × 104/μL: P = 0.013). Among the 514 patients with NBNC-HCC, 194 underwent hepatic resection for nonalcoholic steatohepatitis (NASH) (15%), alcoholic liver disease (ALD) (29%), and cryptogenic hepatitis (56%). Cirrhosis was detected in 72%, 39%, and 16% of patients with NASH, ALD, and cryptogenic hepatitis, respectively. The prevalence of cirrhosis in patients with NASH was significantly higher than the prevalence of cirrhosis in the other groups (P < 0.001). Overall, 70% of the non-malignant liver tissue of patients with NBNC-HCC was not involved with cirrhosis. On the other hand, the median FIB-4 index in patients with cryptogenic HCC was 2.56, which was a significantly lower value than those values in the other groups of patients. The FIB-4 index considered as one of useful screening of HCC. Conclusions The prevalence of NBNC-HCC has increased rapidly even in a regional university hospital. Metabolic syndrome may be an important risk factor for HCC. HCC was also found in patients with non-cirrhotic livers. The FIB-4 index may be a useful screening method for HCC in patients with NBNC.

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Performance of anti-SARS-CoV-2 antibody testing in asymptomatic or mild COVID-19 patients: A retrospective study in outbreak on a cruise ship

PLoS ONE ◽

10.1371/journal.pone.0257452 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0257452

Author(s):

Norihito Kaku ◽

Fumitaka Nishimura ◽

Yui Shigeishi ◽

Rina Tachiki ◽

Hironori Sakai ◽

...

Keyword(s):

False Negative ◽

Enzyme Linked Immunosorbent Assay ◽

Cruise Ship ◽

Igg Antibodies ◽

Antibody Testing ◽

Predictive Values ◽

Blood Samples ◽

Negative Results ◽

Sensitivity Specificity

Objectives A few studies on antibody testing have focused on asymptomatic or mild coronavirus disease 2019 (COVID-19) patients with low initial anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody responses. Anti-SARS-CoV-2 antibody-testing performance was evaluated using blood samples from asymptomatic or mild COVID-19 patients. Methods Blood samples were collected from 143 COVID-19 patients during an outbreak on a cruise ship 3 weeks after diagnosis. Simultaneously, a follow-up SARS-CoV-2 genetic test was performed. Samples stored before the COVID-19 pandemic were also used to evaluate the lateral flow immunochromatographic assay (LFA) and electrochemiluminescence immunoassay (ECLIA). Titers of anti-SARS-CoV-2 IgM and IgG antibodies against the nucleocapsid and spike proteins were measured using the enzyme-linked immunosorbent assay to confirm which antibodies were influenced on LFA- and ECLIA- false-negative result in crew-member samples. Results Sensitivity, specificity, positive-predictive, and negative-predictive values of LFA-detected IgM antibodies were 0.231, 1.000, 1.000, and 0.613, respectively; those of LFA-detected IgG antibodies were 0.483, 0.989, 0.972, and 0.601, respectively; and those of ECLIA-detected total antibodies were 0.783, 1.000, 1.000, and 0.848, respectively. All antibody titers measured using ELISA were significantly lower in blood samples with negative results than in those with positive results in both LFA and ECLIA. In the patients with negative results from the follow-up genetic testing, IgM-, IgG-, and total-antibody positivity rates were 22.9%, 47.6%, and 72.4%, respectively. Conclusions These findings suggest that anti-SARS-CoV-2 antibody testing has lower performance in asymptomatic or mild COVID-19 patients than required in the guidelines.

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Performance Characteristics of Four High-Throughput Immunoassays for Detection of IgG Antibodies against SARS-CoV-2

Journal of Clinical Microbiology ◽

10.1128/jcm.01243-20 ◽

2020 ◽

Vol 58 (8) ◽

Cited By ~ 47

Author(s):

Elitza S. Theel ◽

Julie Harring ◽

Heather Hilgart ◽

Dane Granger

Keyword(s):

High Throughput ◽

High Sensitivity ◽

High Specificity ◽

Cross Reactivity ◽

Clinical Diagnostics ◽

Igg Antibodies ◽

Serum Samples ◽

Predictive Values ◽

Serologic Tests ◽

Convalescent Phase

ABSTRACT The role of serologic testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in both the clinical and public health settings, will continue to evolve as we gain increasing insight into our immune response to the virus. Here, we evaluated four high-throughput serologic tests for detection of anti-SARS-CoV-2 IgG antibodies, from Abbott Laboratories (Abbott Park, IL), Epitope Diagnostics, Inc. (San Diego, CA), Euroimmun (Lubeck, Germany), and Ortho-Clinical Diagnostics (Rochester, NY), using a panel of serially collected serum samples (n = 224) from 56 patients with confirmed coronavirus disease 2019 (COVID-19), healthy donor sera from 2018, and a cross-reactivity serum panel collected in early 2020. The sensitivities of the Abbott, Epitope, Euroimmun, and Ortho-Clinical IgG assays in convalescent-phase serum samples collected more than 14 days post-symptom onset or post-initial positive reverse transcriptase PCR (RT-PCR) result were 92.9% (78/84), 88.1% (74/84), 97.6% (82/84), and 98.8% (83/84), respectively. Among unique convalescent patients, sensitivities of the Abbott, Epitope, Euroimmun, and Ortho-Clinical anti-SARS-CoV-2 IgG assays were 97.3% (36/37), 73% (27/37), 94.6% (35/37), and 97.3% (36/37), respectively. Overall assay specificity/positive predictive values based on a 5% prevalence rate were 99.6%/92.8%, 99.6%/90.6%, 98.0%/71.2%, and 99.6%/92.5%, respectively, for the Abbott, Epitope, Euroimmun, and Ortho-Clinical IgG assays. In conclusion, we show high sensitivity in convalescent-phase sera and high specificity for the Abbott, Euroimmun, and Ortho-Clinical anti-SARS-CoV-2 IgG assays. With the unprecedented influx of commercially available serologic tests for detection of antibodies against SARS-CoV-2, it remains imperative that laboratories thoroughly evaluate such assays for accuracy prior to implementation.

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22-kD Growth hormone exclusion assay: a new approach to measurement of non-22-kD growth hormone isoforms in human blood

Acta Endocrinologica ◽

10.1530/eje.0.1350573 ◽

1996 ◽

Vol 135 (5) ◽

pp. 573-582 ◽

Cited By ~ 25

Author(s):

Cesar L Boguszewski ◽

Lars Hynsjö ◽

Gudmundur Johannsson ◽

Bengt-Åke Bengtsson ◽

Lena MS Carlsson

Keyword(s):

Growth Hormone ◽

Human Blood ◽

Magnetic Beads ◽

Screening Method ◽

Physiological Role ◽

University Hospital ◽

Serum Samples ◽

New Approach ◽

Assay Procedure ◽

Gh Isoforms

Boguszewski CL, Hynsjö L, Johansson G, Bengtsson B-Å, Carlsson LMS. 22-kD Growth hormone exclusion assay: a new approach to measurement of non-22-kD growth hormone isoforms in human blood. Eur J Endocrinol 1996;135:573–82. ISSN 0804–4643 Human growth hormone (GH) exists in a variety of isoforms. In the pituitary, the most abundant isoform is 22-kD GH (22 K GH), while other isoforms (non-22 K GH) are present in variable amounts. In human plasma, the GH heterogeneity contributes to the wide variability in GH levels measured by different immunoassays. The physiological role of the non-22 K GH isoforms is poorly understood, but they may represent a spectrum of agonists or antagonists of the GH receptor. It is possible that increased amounts of non-22 K GH isoforms in the circulation contribute to the growth failure observed in some short children and may be involved in the pathophysiology of acromegaly and other unrelated diseases. Currently, there is no method available to evaluate the ratio of non-22 K GH isoforms to total GH in large sets of serum samples. In this report, a novel assay procedure is described in which monomeric and dimeric isoforms of 22 K GH are removed from serum and non-22 K GH isoforms are quantitated. The 22 K GH exclusion assay (22 K GHEA) was established as a screening method to identify conditions in which the ratio of non-22 K GH isoforms to total GH in human blood is altered. A 22 K GH-speciflc monoclonal antibody (MCB) is used for binding to 22 K GH in serum. Magnetic beads coated with rat anti-mouse immunoglobulin G and a magnetic device are used to remove the 22 K GH-MCB complexes from serum. The non-22 K GH isoforms are measured by a polyclonal antibody-based immunoradiometric assay (GH-IRMA). The assay procedure was optimized systematically by statistical experimental designs. In serum spiked with monomeric or dimeric 22 K GH, the 22 K GH extraction was efficient at GH levels up to 100 μg/l (range 96.3–100%). The intra- and interassay precision for non-22 K GH levels of 3.9 μg/l were 2.6% and 8.7%, respectively, while for levels of 0.6 μg/l, which were very close to the detection limits of the assay, the coefficients were 17.0% and 21.6%, respectively. The percentage of non-22 K GH isoforms determined in serum samples from three different groups of subjects showed clearly distinctive values. The 22 K GHEA is a new method for evaluation of non-22 K GH isoforms in human blood under different physiological and pathophysiological conditions. Cesar L Boguszewski, RCEM, Sahlgrenska University Hospital, Bruna Stråket, 16 S-413 45 Göteborg, Sweden

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Anti-NMDA receptor encephalitis and nonencephalitic HSV-1 infection

Neurology Neuroimmunology & Neuroinflammation ◽

10.1212/nxi.0000000000000458 ◽

2018 ◽

Vol 5 (4) ◽

pp. e458 ◽

Cited By ~ 30

Author(s):

Amy Salovin ◽

Jason Glanzman ◽

Kylie Roslin ◽

Thais Armangue ◽

David R. Lynch ◽

...

Keyword(s):

Nmda Receptor ◽

Igg Antibodies ◽

Antibody Testing ◽

Serum Samples ◽

Herpes Simplex Virus 1 ◽

Barr Virus ◽

Nmda Receptor Encephalitis ◽

Epstein Barr ◽

Simplex Virus ◽

Hsv 1

ObjectiveTo determine whether there is an association between nonencephalitic herpes simplex virus 1 (HSV-1) infection and anti-NMDA receptor encephalitis (anti-NMDARE).MethodsAntibody testing was performed using samples from 2 cohorts in a case-control observational study. The cohort “Philadelphia” included 16 serum samples of pediatric anti-NMDARE cases and 42 age-matched controls with other neuroinflammatory disorders studied at the Children's Hospital of Philadelphia and University of Pennsylvania. The cohort “Barcelona” contained 23 anti-NMDARE patient samples and 26 age-matched participants with other neuroinflammatory disorders studied at IDIBAPS-Hospital Clinic, University of Barcelona. The presence of HSV-1 IgG antibodies was examined by ELISA. As an additional control, IgG antibodies to cytomegalovirus (CMV) and Epstein-Barr virus viral capsid antigen (EBV-VCA) were determined.ResultsIn each cohort, more participants with anti-NMDARE than controls had anti-HSV-1 IgG antibodies. In the Philadelphia cohort (58 participants), 44% of anti-NMDARE cases had antibodies to HSV-1 compared with 14% controls (OR 4.67, 95% CI 1.3–17.3, p = 0.031). In the Barcelona cohort (49 participants), 52% of participants with anti-NMDARE had antibodies to HSV-1 compared with 31% of controls (OR 2.45, 95% CI 0.7–7.9, p = 0.155). Overall, 49% of anti-NMDARE cases have antibodies to HSV-1 in these 2 combined cohorts compared with 21% of controls (Mantel-Haenszel OR 3.21, 95% CI 1.3–7.7, p = 0.007).ConclusionPast HSV-1 infection was found in significantly more anti-NMDARE cases than controls. This suggests a meaningful association between nonencephalitic HSV-1 infection and development of anti-NMDARE.

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A PROSPECTIVE STUDY TO ANALYZE THE SPECIFICITY OF CHLAMYDIAL HEAT SHOCK PROTEIN (CHSP60) ANTIBODIES TO DIAGNOSE TUBAL INFERTILITY

Wiadomości Lekarskie ◽

10.36740/wlek202102102 ◽

2021 ◽

Vol 74 (2) ◽

pp. 184-189

Author(s):

Vladyslav O. Berestoviy ◽

Inna V. Sokol ◽

Ahmad A. Mahmood ◽

Valentyna G. Ginzburg ◽

Dmytro O. Govsieiev

Keyword(s):

Heat Shock ◽

Heat Shock Protein ◽

Enzyme Linked Immunosorbent Assay ◽

Heat Shock Protein 60 ◽

Igg Antibodies ◽

Antibody Testing ◽

Tubal Infertility ◽

Factor Alpha ◽

A Prospective Study ◽

Specific Evaluation

The aim: To investigate the utility of testing for chlamydial heat shock protein 60 (CHSP60) antibodies in the diagnosis of tubal infertility. Materials and methods: All the collected samples were assayed for IgM and IgG antibodies to chlamydia trachomatis and chlamydial heat shock protein 60 (CHSP60) by using immunofluorescence and enzyme-linked immunosorbent assay (ELISA) techniques, respectively. Results: There were no substantial differences between antibodies to C. trachomatis in females with tubal infertility (67%) and non-tubal infertility (48%). However, women with tubal infertility (45%) have more anti-CHSP60 antibodies than non-tubal infertility (9%). Antibody screening for C. trachomatis has only (63%) sensitivity and (54%) specificity for detecting tubal infertility. On the other hand, the CHSP60 antibody testing has (44%) sensitivity and 92% specificity for diagnosing tubal infertility. A positive microimmunofluorescence (MIF) titer was observed in 12 of 18 (67%) females with the tubal problem, 31 of 64 (48%) with non-tubal infertility (P=0.3, OR=2.2, 95% CI=0.71 to 8.01). The CHSP60 antibodies were found in 8 of 18 (45%) females with tubal problem & 6 of 64 (9%) women with non-tubal infertility, power factor alpha α P=0.004, OR=9.3, 95% CI=2.1 to 43.2, power= 1.002 for n= 0.05). Incorporating CHSP60 and C. trachomatis antibodies testing gives an excellent positive probability proportion of 10 to diagnose C. trachomatis associated tubal infertility. Conclusions: CHSP60 antibody testing is a more specific evaluation than antibody testing for C. trachomatis for predicting chlamydia-associated tubal infertility. Using these tests at the first infertility examination may help the immediate diagnosis for non-interceptive tubal infertility.

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Comparative Immunoglobulin G Antibody Profiles between Mother and Child (CGMC Test) for Early Diagnosis of Congenital Toxoplasmosis

Journal of Clinical Microbiology ◽

10.1128/jcm.38.10.3619-3622.2000 ◽

2000 ◽

Vol 38 (10) ◽

pp. 3619-3622 ◽

Cited By ~ 23

Author(s):

Uwe Gross ◽

Carsten G. K. Lüder ◽

Vera Hendgen ◽

Cornelia Heeg ◽

Irmtraud Sauer ◽

...

Keyword(s):

Early Diagnosis ◽

Newborn Infant ◽

Newborn Infants ◽

Congenital Toxoplasmosis ◽

Congenital Infection ◽

Igg Antibodies ◽

Serum Samples ◽

Predictive Values ◽

Iga Antibodies ◽

Mother And Child

Early diagnosis of congenital toxoplasmosis is rendered difficult when specific immunoglobulin M (IgM) and/or IgA antibodies are absent in the blood of the newborn infant. Since maternal IgG antibodies can cross the placenta, determination of IgG antibodies in newborn infants has hitherto not been used routinely for the diagnosis of congenital infection. The aim of this study was to assess the diagnostic usefulness of an immunoblot assay which compares the early IgG profiles between the mother and her child (comparative IgG profile between mother and child; CGMC test) directed against a total cell lysate ofToxoplasma gondii tachyzoites. Serum samples from 97 newborn infants at risk of toxoplasma infection were obtained from umbilical cord blood at birth or postnatally until 3 months of life and were directly compared with serum samples from the respective mothers. Congenital toxoplasmosis was diagnosed only when IgG-reactive protein bands that were present in any newborn serum samples were absent in the corresponding maternal serum sample. Congenital infection was defined by conventional serological assays when IgM and/or IgA antibodies were present in newborn infant blood or when IgG titers rose within the first 12 months or were persistently stable for more than 8 months. Using these criteria, congenital infection was definitely confirmed in 11 cases. Three additional cases were diagnosed based on indicative data. The CGMC test, which was performed without knowledge of the results of conventional serologal assays, had sensitivity and specificity of 82.4 and 93.0%, respectively, and positive and negative predictive values of 73.7 and 95.7%, respectively. When true positives and true negatives were considered, the comparative IgG profile had a ratio of 90.9% true results. The CGMC test thus is useful as an additional assay for the rapid diagnosis of congenital toxoplasmosis when paired serum samples from mother and child are available.

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