scholarly journals Development of a Highly Sensitive and Specific Blastomycosis Antibody Enzyme Immunoassay Using Blastomyces dermatitidis Surface Protein BAD-1

2013 ◽  
Vol 21 (2) ◽  
pp. 143-146 ◽  
Author(s):  
Sarah M. Richer ◽  
Melinda L. Smedema ◽  
Michelle M. Durkin ◽  
T. Tristan Brandhorst ◽  
Chadi A. Hage ◽  
...  
Keyword(s):  
Enzyme Immunoassay ◽  
Surface Protein ◽  
Antibody Detection ◽  
Blastomyces Dermatitidis ◽  
Antibody Testing ◽  
Content Type ◽  
Negative Results ◽  
Highly Sensitive ◽  
Low Sensitivity ◽  
Antigen Testing

ABSTRACTSerologic tests for antibodies toBlastomyces dermatitidisare not thought to be useful for the diagnosis of blastomycosis, in part due to the low sensitivity of immunodiffusion and complement fixation. Earlier studies have shown that the enzyme immunoassay improves the sensitivity of antibody detection for the diagnosis of blastomycosis. Microplates coated with theB. dermatitidissurface protein BAD-1 were used for testing sera from patients with proven blastomycosis or histoplasmosis and controls. Semiquantification was accomplished by using standards containing human anti-B. dermatitidisantibodies. The antibodies were detected in 87.8% of the patients with blastomycosis by the enzyme immunoassay compared to 15.0% by immunodiffusion. The specificities were 99.2% for patients with nonfungal infections and healthy subjects and 94.0% for patients with histoplasmosis. The results were highly reproducible on repeat testing. When combined with antigen testing, antibody testing improved the sensitivity from 87.8% to 97.6%. Enzyme immunoassay detection of antibodies against BAD-1 is highly specific, has greatly improved sensitivity over immunodiffusion, and may identify cases with negative results by antigen testing. This assay has the potential to aid in the diagnosis of blastomycosis.

scholarly journals Evaluation of Recombinant Proteins of Burkholderia mallei for Serodiagnosis of Glanders

2012 ◽  
Vol 19 (8) ◽  
pp. 1193-1198 ◽  
Author(s):  
Vijai Pal ◽  
Subodh Kumar ◽  
Praveen Malik ◽  
Ganga Prasad Rai
Keyword(s):  
Sensitivity And Specificity ◽  
Recombinant Proteins ◽  
False Negative ◽  
Enzyme Linked Immunosorbent Assay ◽  
Burkholderia Mallei ◽  
Content Type ◽  
Whole Cells ◽  
Negative Results ◽  
Elisa Format ◽  
Low Sensitivity

ABSTRACTGlanders is a contagious disease caused by the Gram-negative bacillusBurkholderia mallei. The number of equine glanders outbreaks has increased steadily during the last decade. The disease must be reported to the Office International des Epizooties, Paris, France. Glanders serodiagnosis is hampered by the considerable number of false positives and negatives of the internationally prescribed tests. The major problem leading to the low sensitivity and specificity of the complement fixation test (CFT) and enzyme-linked immunosorbent assay (ELISA) has been linked to the test antigens currently used, i.e., crude preparations of whole cells. False-positive results obtained from other diagnostic tests utilizing crude antigens lead to financial losses to animal owners, and false-negative results can turn a risk into a possible threat. In this study, we report on the identification of diagnostic targets using bioinformatics tools for serodiagnosis of glanders. The identified gene sequences were cloned and expressed as recombinant proteins. The purified recombinant proteins ofB. malleiwere used in an indirect ELISA format for serodiagnosis of glanders. Two recombinant proteins, 0375H and 0375TH, exhibited 100% sensitivity and specificity for glanders diagnosis. The proteins also did not cross-react with sera from patients with the closely related disease melioidosis. The results of this investigation highlight the potential of recombinant 0375H and 0375TH proteins in specific and sensitive diagnosis of glanders.

scholarly journals Evaluation of Coccidioides Antigen Detection in Dogs with Coccidioidomycosis

2012 ◽  
Vol 19 (3) ◽  
pp. 343-345 ◽  
Author(s):  
Emily J. Kirsch ◽  
Russell T. Greene ◽  
Annalisa Prahl ◽  
Stanley I. Rubin ◽  
Jane E. Sykes ◽  
...  
Keyword(s):  
Enzyme Immunoassay ◽  
Fungal Infections ◽  
Rapid Diagnosis ◽  
Antigen Detection ◽  
Antibody Testing ◽  
Content Type ◽  
Healthy Dogs ◽  
Galactomannan Antigen ◽  
Antigen Antibody ◽  
Urine And Serum

ABSTRACTAntigen detection has been reported to be a promising method for rapid diagnosis of coccidioidomycosis in humans.Coccidioidesantigen detection has not been previously reported in dogs with coccidioidomycosis and was evaluated in 60 cases diagnosed based on detection of anti-Coccidioidesantibodies at titers of 1:16 or more in serum. Controls included dogs with presumed histoplasmosis or blastomycosis, other fungal infections, or nonfungal diseases and healthy dogs. Urine and serum specimens were tested using an enzyme immunoassay forCoccidioidesgalactomannan antigen. Antibody testing was performed at commercial veterinary reference laboratories. Antigen was detected in urine or serum of 12 of 60 (20.0%), urine only in 2 of 57 (3.5%), and serum only in 11 of 58 (19.0%) dogs with coccidioidomycosis. Antigen was detected in the urine of 3 of 43 (7.0%) and serum of 1 of 37 (2.7%) dogs with histoplasmosis or blastomycosis but not in 13 dogs with other fungal infections (serum, 9; urine, 13), 41 dogs with nonfungal diseases (urine, 41; serum, 18), or healthy dogs (serum, 21; urine, 21). Detection of antigen was an insensitive method for diagnosis of coccidioidomycosis in dogs in which the diagnosis was based primarily upon detection of antibodies at titers of 1:16 or higher, and the highest sensitivity was in serum.

scholarly journals Enhanced Antibody Detection and Diagnosis of Coccidioidomycosis with the MiraVista IgG and IgM Detection Enzyme Immunoassay

2017 ◽  
Vol 55 (3) ◽  
pp. 893-901 ◽  
Author(s):  
Joshua Malo ◽  
Eric Holbrook ◽  
Tirdad Zangeneh ◽  
Chris Strawter ◽  
Eyal Oren ◽  
...  
Keyword(s):  
Enzyme Immunoassay ◽  
Complement Fixation ◽  
Community Acquired Pneumonia ◽  
Antibody Detection ◽  
Serum Samples ◽  
Content Type ◽  
Appropriate Treatment ◽  
Detection And Diagnosis ◽  
Disseminated Disease ◽  
Improved Accuracy

ABSTRACT Coccidioidomycosis is a common cause of community-acquired pneumonia in areas of the southwestern United States in which the disease is endemic. Clinical presentations range from self-limited disease to severe disseminated disease. Therefore, early and accurate diagnosis is essential to ensure appropriate treatment and monitoring. Currently available diagnostic tests have variable accuracy, particularly in certain patient populations, and new tests may offer improved accuracy for the diagnosis of coccidioidomycosis. Serum samples from 103 cases of coccidioidomycosis and 373 controls were tested for IgG and IgM antibodies using the MVista anti- Coccidioides antibody enzyme immunoassay. Serum specimens from 170 controls from areas in which the disease is endemic and 44 cases were tested by immunodiffusion at MiraVista Diagnostics. The sensitivity of the MVista antibody assay was 88.3%, and the specificity was 90%. The sensitivity was maintained in the presence of immunocompromising conditions or immunosuppressive therapies. The sensitivity of immunodiffusion was 60.2%, and the specificity was 98.8%. The sensitivity of complement fixation (62 cases) was 66.1%, but the specificity could not be determined. The MVista anti- Coccidioides antibody enzyme immunoassay offers improved sensitivity, compared with immunodiffusion and complement fixation, is not impaired in immunocompromised patients, and permits highly reproducible semiquantification.

scholarly journals Antibody testing for COVID-19: A report from the National COVID Scientific Advisory Panel

2020 ◽  
Vol 5 ◽  
pp. 139 ◽  
Author(s):  
Emily R. Adams ◽  
Mark Ainsworth ◽  
Rekha Anand ◽  
Monique I. Andersson ◽  
Kathryn Auckland ◽  
...  
Keyword(s):  
Symptom Onset ◽  
Vaccine Development ◽  
Detection Threshold ◽  
Negative Control ◽  
Antibody Detection ◽  
Advisory Panel ◽  
Antibody Testing ◽  
Highly Sensitive ◽  
History Of ◽  
The Uk

Background: The COVID-19 pandemic caused >1 million infections during January-March 2020. There is an urgent need for reliable antibody detection approaches to support diagnosis, vaccine development, safe release of individuals from quarantine, and population lock-down exit strategies. We set out to evaluate the performance of ELISA and lateral flow immunoassay (LFIA) devices. Methods: We tested plasma for COVID (severe acute respiratory syndrome coronavirus 2; SARS-CoV-2) IgM and IgG antibodies by ELISA and using nine different LFIA devices. We used a panel of plasma samples from individuals who have had confirmed COVID infection based on a PCR result (n=40), and pre-pandemic negative control samples banked in the UK prior to December-2019 (n=142). Results: ELISA detected IgM or IgG in 34/40 individuals with a confirmed history of COVID infection (sensitivity 85%, 95%CI 70-94%), vs. 0/50 pre-pandemic controls (specificity 100% [95%CI 93-100%]). IgG levels were detected in 31/31 COVID-positive individuals tested ≥10 days after symptom onset (sensitivity 100%, 95%CI 89-100%). IgG titres rose during the 3 weeks post symptom onset and began to fall by 8 weeks, but remained above the detection threshold. Point estimates for the sensitivity of LFIA devices ranged from 55-70% versus RT-PCR and 65-85% versus ELISA, with specificity 95-100% and 93-100% respectively. Within the limits of the study size, the performance of most LFIA devices was similar. Conclusions: Currently available commercial LFIA devices do not perform sufficiently well for individual patient applications. However, ELISA can be calibrated to be specific for detecting and quantifying SARS-CoV-2 IgM and IgG and is highly sensitive for IgG from 10 days following first symptoms.

scholarly journals Antibody testing for COVID-19: A report from the National COVID Scientific Advisory Panel

2020 ◽  
Author(s):  
◽  
Emily R Adams ◽  
Mark Ainsworth ◽  
Rekha Anand ◽  
Monique I Andersson ◽  
...  
Keyword(s):  
Symptom Onset ◽  
Vaccine Development ◽  
Detection Threshold ◽  
Negative Control ◽  
Antibody Detection ◽  
Advisory Panel ◽  
Antibody Testing ◽  
Highly Sensitive ◽  
History Of ◽  
The Uk

ABSTRACTBackgroundThe COVID-19 pandemic caused >1 million infections during January-March 2020. There is an urgent need for reliable antibody detection approaches to support diagnosis, vaccine development, safe release of individuals from quarantine, and population lock-down exit strategies. We set out to evaluate the performance of ELISA and lateral flow immunoassay (LFIA) devices.MethodsWe tested plasma for COVID (SARS-CoV-2) IgM and IgG antibodies by ELISA and using nine different LFIA devices. We used a panel of plasma samples from individuals who have had confirmed COVID infection based on a PCR result (n=40), and pre-pandemic negative control samples banked in the UK prior to December-2019 (n=142).ResultsELISA detected IgM or IgG in 34/40 individuals with a confirmed history of COVID infection (sensitivity 85%, 95%CI 70-94%), vs. 0/50 pre-pandemic controls (specificity 100% [95%CI 93-100%]). IgG levels were detected in 31/31 COVID-positive individuals tested ≥10 days after symptom onset (sensitivity 100%, 95%CI 89-100%). IgG titres rose during the 3 weeks post symptom onset and began to fall by 8 weeks, but remained above the detection threshold. Point estimates for the sensitivity of LFIA devices ranged from 55-70% versus RT-PCR and 65-85% versus ELISA, with specificity 95-100% and 93-100% respectively. Within the limits of the study size, the performance of most LFIA devices was similar.ConclusionsCurrently available commercial LFIA devices do not perform sufficiently well for individual patient applications. However, ELISA can be calibrated to be specific for detecting and quantifying SARS-CoV-2 IgM and IgG and is highly sensitive for IgG from 10 days following first symptoms.

scholarly journals 263. Advances in Diagnosis of Progressive Coccidioidomycos: Experience in 164 Cases and 508 Controls

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S146-S146
Author(s):  
Robert Myers ◽  
Holbrook Eric ◽  
Lawrence J Wheat ◽  
Christelle Kassis ◽  
Michelle Durkin
Keyword(s):  
Retrospective Study ◽  
Sensitivity And Specificity ◽  
Advanced Disease ◽  
Turnaround Time ◽  
Antibody Detection ◽  
Immunocompromised Patients ◽  
Antibody Testing ◽  
Main Method ◽  
Antigen Testing ◽  
Urine And Serum

Abstract Background Antibody detection is the main method for diagnosis of coccidioidomycosis but has limitations including sensitivity and turnaround time. The MVISTA Coccidioides antigen enzyme immunoassay (EIA) is recommended for testing CSF in suspected Coccidioides meningitis. The early reports on urine and serum antigen testing evaluated small numbers of patients who were mostly immunocompromised with advanced disease. Methods A retrospective study, including all patients in whom Coccidioides antigen testing was performed between January 2013 and May 2017, was conducted at Maricopa Integrated Health System (MIHS). Sensitivity and specificity of antigen testing at MiraVista Diagnostics and antibody testing at MIHS or commercial laboratories were evaluated in 164 cases and 508 controls. Results The sensitivity of antigen testing was 51% and specificity was 99%. The sensitivity of antigen detection was highest if both urine and serum were tested (57%) than if only urine was tested (38%). The sensitivity of antibody testing was 84% and the specificity was 94% by immunodiffusion (ID). The sensitivity and specificity of antigen or ID antibody testing both were 94%. Sensitivity of antigen testing was 57% in proven and 58% in probable cases, ID antibody in 85% of proven and 75% of probable and antigen or ID antibody in 93% of proven and 95% of probable cases. Antigen was detected more often in disseminated (79%) than pulmonary cases (42%) as was ID antibody, 91% and 79%, respectively. Antigen testing was more sensitive in immunocompromised (76%) than non-immunocompromised patients (41%) while ID antibody was less sensitive in immunocompromised (74%) than in non-immunocompromised patients (93%). Combined antigen and ID antibody testing provided the highest sensitivity, 94% in all cases, 94% in immunocompromised and 95% in non-immunocompromised patients. Conclusion These findings support testing urine and serum for Coccidioides antigen and serum for ID antibodies for diagnosis of progressive pulmonary or disseminated coccidioidomycosis. Disclosures All authors: No reported disclosures.

Detection of Blastomyces dermatitidis antigen in urine using a commercially available, quantitative enzyme immunoassay

2021 ◽  
Author(s):  
Elitza S. Theel ◽  
Kyle G. Rodino ◽  
Dane Granger
Keyword(s):  
Enzyme Immunoassay ◽  
Medical Records ◽  
Laboratory Diagnosis ◽  
Antigen Detection ◽  
Blastomyces Dermatitidis ◽  
Quantitative Detection ◽  
Negative Results ◽  
Two Samples ◽  
Comparable Performance ◽  
Combination Of Methods

Laboratory diagnosis of blastomycosis relies on a combination of methods, including antigen detection. We assessed performance of analyte specific reagents from Gotham Biotech (Portland, ME) for quantitative detection of Blastomyces dermatitidis galactomannan (GM) in urine using an enzyme immunoassay (EIA), compared to the Blastomyces quantitative EIA from MiraVista Diagnostics (Indianapolis, IN). Residual urine from 232 unique patients previously tested by the MiraVista assay were evaluated using the Gotham EIA, which showed 97.4% (74/76), 100% (156/156), and 99.1% (230/232) positive, negative, and overall agreement, respectively. Correlation between the quantitative B. dermatitidis antigen levels by the Gotham and MiraVista EIAs was low (R 2 =0.20). Medical records were available for 36 of the 232 patients, among whom four had confirmed blastomycosis and both the Gotham and MiraVista EIAs were positive. Nine of these patients had histoplasmosis, and the Gotham and MiraVista EIAs yielded negative results in 44.4% (4/9) and 22.2% (2/9) of cases, respectively. Both assays were negative in the remaining 23 patients. Post-laboratory implementation of the Gotham EIA, chart reviews were performed on the first 50 unique patients (51 samples) tested by the assay in our hospital. Among these, 3/50 (6%) samples were positive by the Gotham EIA; two samples from a patient with culture-confirmed blastomycosis and one from a patient with histoplasmosis (also positive by the MiraVista Blastomyces EIA). All remaining patients were negative by the Gotham EIA and had alternative diagnoses. Our findings show comparable performance between the Gotham and MiraVista quantitative EIAs for detection of B. dermatitidis GM in urine.

scholarly journals The utility of Coccidioides antigen and antibody detection in cerebrospinal fluid in the diagnosis of canine central nervous system coccidioidomycosis

2022 ◽  
pp. 1-5
Author(s):  
Christine D. Butkiewicz ◽  
Cody J. Alcott ◽  
Janelle Renschler ◽  
Lawrence J. Wheat ◽  
Lisa F. Shubitz
Keyword(s):  
Clinical Signs ◽  
High Specificity ◽  
Antibody Detection ◽  
Antibody Testing ◽  
Endemic Region ◽  
Predictive Values ◽  
Csf Analysis ◽  
Neurologic Disorders ◽  
Low Sensitivity ◽  
A Prospective Study

Abstract OBJECTIVE To evaluate the utility of enzyme immunoassays (EIAs) for the detection of Coccidioides antigen and antibody in CSF in the diagnosis of CNS coccidioidomycosis in dogs. ANIMALS 51 dogs evaluated for CNS disease in a single specialty center in Tucson in 2016. PROCEDURES Excess CSF after routine analysis was banked after collection from dogs presented to the neurology service. Samples were tested by EIA for presence of Coccidioides antigen and antibody. Clinical data were collected from medical records retrospectively. RESULTS 22 dogs were diagnosed with CNS coccidioidomycosis (CCM) or another neurologic disease (non-CCM). These groups of dogs overlapped in the presenting complaints, MRI results, and routine CSF analysis results. Four dogs, all with CCM, had positive antigen EIA results. With clinical diagnosis used as the reference standard, CSF antigen testing had low sensitivity (20%) but high specificity (100%) for diagnosis of CCM. Ten dogs with CCM and 4 dogs with other diagnoses had antibody detected in CSF by EIA. Sensitivity of CSF antibody testing was 46%, specificity was 86%, and positive and negative predictive values for the study population were 71% and 68%, respectively. Clinical Relevance Diagnosis of CNS coccidioidomycosis in dogs in an endemic region was hampered by overlap of clinical signs with other neurologic disorders and the low sensitivity of confirmatory diagnostics. The evaluated Coccidioides-specific EIAs performed on CSF can aid in the diagnosis. A prospective study is warranted to corroborate and refine these preliminary findings

scholarly journals Comparasion of polyacrylamide gel electrophoresis (PAGE), immuno-electron microscopy (IEM) and enzyme immunoassay (EIA) for the rapid diagnosis of rotavirus infection in children

1983 ◽  
Vol 78 (4) ◽  
pp. 483-490 ◽  
Author(s):  
H. G. Pereira ◽  
R. S. Azeredto ◽  
F. Sutmoller ◽  
J. P. Leite ◽  
V. de Farias ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Enzyme Immunoassay ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polyacrylamide Gel ◽  
Complete Agreement ◽  
Diagnostic Assay ◽  
Negative Results ◽  
Highly Sensitive ◽  
Immuno Electron Microscopy

Detection of rotavirus RNA by polyacrylamide gel electrophoresis (PAGE) proved to be a highly sensitive and rapid diagnostic test. A comparison of this assay with immuno-electron microscopy (IEM) and enzyme immunoassay (EIA) in 245 faeces from children with gastroenteritis revealed complete agreement between the three assays in 238 (97.14%) samples. Among 75 samples positive in at least one of the three assays, negative results were observed in 5 (6.48%) by PAGE, in 6 (6.76%) by EIA and in none by IEM. Silver staining greatly increased the sensitivity of the PAGE assay. We conclude that although IEM remains the most sensitive and rapid rotavirus diagnostic assay, the PAGE technique has many advantages in its favour, including the non-requirement of expensive equipment, the use of only chemically defined reagents and the capacity to distinguish virus subgroup and variants and to detect non-crossreactive rotaviruses which are missed in serological assays.

scholarly journals Potential False-Positive and False-Negative Results for COVID-19 IgG/IgM Antibody Testing After Heat-Inactivation

2021 ◽  
Vol 7 ◽  
Author(s):  
Jie Lin ◽  
Wei Dai ◽  
Weiwei Li ◽  
Li Xiao ◽  
Tao Luo ◽  
...  
Keyword(s):  
False Negative ◽  
Antibody Detection ◽  
Heat Inactivation ◽  
Antibody Testing ◽  
Igg Antibody ◽  
Igm Antibody ◽  
Negative Results ◽  
False Negative Results ◽  
Specific Igg ◽  
Potential False Positive

Objectives: With the worldwide spread of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), various antibody detection kits have been developed to test for SARS-CoV-2– specific IgG, IgM, and total antibody. However, the use of different testing methods under various heat-inactivation conditions might affect the COVID-19 detection results.Methods: Seven different antibody detection kits produced by four manufacturers for detection of SARS-CoV-2 IgG, IgM, and total antibody were tested at Wuhan Huoshenshan Hospital, China. Most of the kits used the indirect immunity, capture, and double-antigen sandwich methods. The effects of various heat-inactivation conditions on SARS-CoV-2-specific IgG, IgM, and total antibody detection were analyzed for the different test methods.Results: Using the indirect immunity method, values for SARS-CoV-2 IgG antibody significantly increased and those for IgM antibody decreased with increasing temperature of heat-inactivation using indirect immunity method. However, values for SARS-CoV-2 IgM and total antibody showed no change when the capture and double-antigen sandwich methods were used. The changes in IgG and IgM antibody values with the indirect immunity method indicated that heat-inactivation could affect COVID-19 detection results obtained using this method. In particular, 18 (22.2%) SARS-CoV-2 IgM positive samples were detected as negative with heat-inactivation at 65°C for 30 min, and one (25%) IgG negative sample was detected as positive after heat-inactivation at 56°C for 60 min and 60°C for 30 min.Conclusions: Heat-inactivation could increase SARS-CoV-2 IgG antibody values, and decrease IgM antibody values, causing potential false-positive or false-negative results for COVID-19 antibody detection using the indirect immunity method. Thus, before conducting antibody testing, the testing platforms should be evaluated in accordance with the relevant requirements to ensure accurate COVID-19 detection results.

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