Serologic Diagnosis of Whooping Cough by an Enzyme-Linked Immunosorbent Assay Using Fimbrial Hemagglutinin as Antigen

Objective. To study the features of the clinic and serological diagnosis of pertussis in adults. Patients and methods. The study included patients admitted to Infectious diseases clinical hospital No 1 in 2018 with prolonged cough syndrome. Clinical methods were used for monitoring adult patients with pertussis. Information about the course of the disease is recorded in the "case histories" and clinical observation cards. To verify whooping cough, blood was examined to detect anti-pertussis antibodies of class IgM, IgG, IgA using an enzyme-linked immunosorbent assay (RIDASCRЕЕN, R-Bioрharm AG). Results. In total, 52 patients were included in the study, among which pertussis was verified in 57.7–6.8% of patients. Using the generally accepted classification in 26.6–8.0% of patients, pertussis proceeded in a mild form, in 66.7–8.6% in moderate and in 6.7–4.5% in severe form. The presented clinical characteristics of pertussis in adults debunk the myth of the supposedly mild course of the disease in this population. A description of the severe course of whooping cough in an elderly patient is presented. A feature of the formation of post-infectious immunity in adults is, along with the development of IgG class antibodies starting from the 3rd week of the disease, the rapid accumulation of IgA class antibodies in the absence of IgM class antibodies. Conclusion. A detailed description of the clinical symptoms of pertussis in adults will improve the doctors' awareness of the clinical verification of pertussis. The effectiveness and prospects of using the enzyme-linked immunosorbent assay for the diagnosis of pertussis in adults with a single study, starting from the 3rd week from the onset of the disease, are proved. Key words: ELISA, whooping cough, clinical forms, serological diagnosis, severity of course

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Evaluation of Euroimmun Anti-Zika Virus IgM and IgG Enzyme-Linked Immunosorbent Assays for Zika Virus Serologic Testing

Journal of Clinical Microbiology ◽

10.1128/jcm.00442-17 ◽

2017 ◽

Vol 55 (8) ◽

pp. 2462-2471 ◽

Cited By ~ 59

Author(s):

Arnaud G. L'Huillier ◽

Anne Hamid-Allie ◽

Erik Kristjanson ◽

Louis Papageorgiou ◽

Sam Hung ◽

...

Keyword(s):

Public Health ◽

Immunosorbent Assay ◽

Zika Virus ◽

Neutralization Test ◽

Enzyme Linked Immunosorbent Assay ◽

Convenience Sample ◽

Plaque Reduction Neutralization Test ◽

Serologic Diagnosis ◽

Serologic Testing ◽

Antibody Capture

ABSTRACTWith the emerging Zika virus (ZIKV) epidemic, serologic diagnosis relies on a labor-intensive IgM antibody capture enzyme-linked immunosorbent assay (MAC-ELISA) and confirmation by a plaque reduction neutralization test (PRNT). To streamline serologic testing, several commercial assays have been developed. Our aim was to compare the commercial Euroimmun anti-ZIKV IgM and IgG assays to the reference MAC-ELISA and PRNT currently in use. Serum specimens submitted to Public Health Ontario Laboratory, Canada, were tested for IgM and IgG using the Euroimmun assays and the results were compared with those from MAC-ELISA. The PRNT was performed on positive or equivocal specimens using either MAC-ELISA or Euroimmun assays, MAC-ELISA-inconclusive specimens, and a convenience sample of specimens negative by both assays (cohort 1). Another set of specimens selected on the basis of PRNT results was subsequently tested by the Euroimmun assays (cohort 2). MAC-ELISA was positive, equivocal, negative, and inconclusive in 57/223, 15/223, 147/223, and 4/223 specimens, respectively. Among the 76 specimens that were MAC-ELISA positive, equivocal, or inconclusive, 30 (39.5%) were Euroimmun IgM and/or IgG positive or equivocal. Among the 147 MAC-ELISA-negative specimens, 136 (92.5%) were Euroimmun IgM and IgG negative. The sensitivity of the combined Euroimmun IgM/IgG against the PRNT was 83% (cohort 1) and 92% (cohort 2), whereas the specificity was 81% (cohort 1) and 65% (cohort 2). The combined Euroimmun IgM/IgG showed good specificity (92.5%) but suboptimal sensitivity (39.5%) compared with that of the MAC-ELISA. However, the sensitivity of the combined Euroimmun IgM/IgG against the PRNT was significantly higher (83 to 92%). More studies are needed before commercial assays are implemented for routine ZIKV serologic diagnosis.

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Detection of False-Positive Sera in Contagious Agalactia with a Multiantigen ELISA and their Elimination with a Protein G Conjugate

Journal of Veterinary Diagnostic Investigation ◽

10.1177/104063879801000403 ◽

1998 ◽

Vol 10 (4) ◽

pp. 326-330 ◽

Cited By ~ 12

Author(s):

Maurice Lambert ◽

Michel Calamel ◽

Philippe Dufour ◽

Evelyne Cabasse ◽

Christian Vitu ◽

...

Keyword(s):

Monoclonal Antibodies ◽

Immunosorbent Assay ◽

False Positive ◽

Enzyme Linked Immunosorbent Assay ◽

Protein G ◽

Mycoplasma Agalactiae ◽

Cross Reactions ◽

Serologic Diagnosis ◽

Contagious Agalactia ◽

The Past

In serology, lack of specificity can generally be attributed to cross-reactions between different pathogens with antigens bearing similar epitopes. During seroepidemiologic surveys of contagious agalactia of sheep caused by Mycoplasma agalactiae infection, numerous sera were analyzed by enzyme-linked immunosorbent assay (ELISA). A few sera reacted with various antigens coated on plates, including the well with no antigen. This reactivity was not due to cross-reactions as initially suspected, and these multipositive sera were designated false-positive sera. Elimination of this false positivity was not possible by using covalent ELISA plates or different rabbit anti-sheep IgG conjugates. Only conjugates using monoclonal antibodies or protein G were efficient in elimination of false positivities without reducing the true specific positive titers. No false-positive sera have been observed since the implementation of protein G conjugates in the serologic diagnosis of contagious agalactia by ELISA for the past 2 years.

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