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 False-Positive Results Obtained with the Alexon ProSpecT Cryptosporidium Enzyme Immunoassay

1999 ◽  
Vol 37 (5) ◽  
pp. 1582-1583 ◽  
Author(s):  
Kirk M. Doing ◽  
Jill L. Hamm ◽  
Jo Ann Jellison ◽  
Jessica A. Marquis ◽  
Cindy Kingsbury
Keyword(s):  
Enzyme Immunoassay ◽  
False Positive ◽  
Antigen Detection ◽  
Immunocompromised Patients ◽  
Careful Attention ◽  
Iodine Staining ◽  
Negative Results ◽  
Food Borne ◽  
Positive Results

Cryptosporidium is known to cause diarrhea in immunocompromised patients and is also associated with outbreaks of disease due to food-borne and waterborne parasites. Traditional procedures, involving iodine staining of wet mounts of stool sediments and trichrome staining, lack the sensitivity to detectCryptosporidium. Special staining procedures, such as the modified acid-fast and safranin stains, are generally employed. Less labor-intensive antigen detection assays have simplified detection; however, careful attention to local epidemiology is important because false-positive tests occur. Here, we report two incidents involving 62 false-positive results obtained with the Alexon ProSpecTCryptosporidium enzyme immunoassay, which were deemed false-positive based on negative results obtained from extensive microscopic examinations.

scholarly journals Comparison of three laboratorial tests for diagnosis of canine parvovirus infection

2013 ◽  
Vol 65 (1) ◽  
pp. 149-152 ◽  
Author(s):  
M.M.O. Silva ◽  
T.X. Castro ◽  
E.M. Costa ◽  
T.A.L. Trancoso ◽  
F. Mendes-de-Almeida ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Enzyme Immunoassay ◽  
Antigen Detection ◽  
Canine Parvovirus ◽  
Chain Reaction ◽  
Fecal Samples ◽  
Negative Results ◽  
Rapid Tests ◽  
Polymerase Chain ◽  
One Year

The aim of this study was to evaluate the rapid tests currently used for canine parvovirus (CPV) diagnosis: hemagglutination test (HA), enzyme immunoassay (EIA) and polymerase chain reaction (PCR). A total of 112 fecal samples collected from diarrheic puppies up to one year of age were tested. The EIA was able to detect CPV antigen in 44 samples. By HA, 32 samples tested highly positive with titers >128, eight tested weakly positive (titers 32 and 64) and 72 were negative (titers <16). Using PCR, 57 samples were found positive including 13 EIA-negative and 19 HA-negative samples. The best correlation was observed between EIA and PCR (88.4%). These tests were able to detect all types of CPV, including CPV-2c. Considering that 23%-33% of dogs presenting enteritis did not show infection by EIA nor HA, negative results from the antigen detection tests should be confirmed through molecular methods.

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.

Chronic Wasting Disease Options of Surveillance in Carpathian Cervids: from the Identification of Characteristic Microscopic Pathologic Changes to Prionic Seeded Conversion and Amplification Assays

2001 ◽  
Vol 71 (3) ◽  
pp. 480-486
Author(s):  
Florica Barbuceanu ◽  
Stelian Baraitareanu ◽  
Stefania-Felicia Barbuceanu ◽  
Gabriel Predoi
Keyword(s):  
Enzyme Immunoassay ◽  
Diagnostic Tests ◽  
Chronic Wasting Disease ◽  
Rapid Diagnostic Tests ◽  
Diagnostic Methods ◽  
Wasting Disease ◽  
Western Immunoblotting ◽  
Negative Results ◽  
Antigen Capture ◽  
Confirmatory Tests

This paper describes the current diagnostic methods of Chronic Wasting Disease (CWD) in cervides used between 2013 and 2017 in Romania. The active surveillance of CWD involves the targeted groups screening by using rapid diagnostic tests (e.g., antigen capture enzyme immunoassay). If the first test does not provide certain negative results, then the confirmatory methods have been used, i.e. histopathology, immunohistochemistry and Western immunoblotting. These tests did not lead to the detection of CWD prions (PrPCWD) in Romania. This may be due to the absence or insufficient quantity of PrPCWD in samples, below the threshold of confirmatory tests.

scholarly journals Quantitative detection of messenger RNA by solution hybridization and enzyme immunoassay.

1990 ◽  
Vol 265 (20) ◽  
pp. 11601-11604
Author(s):  
F Coutlee ◽  
E A Rubalcaba ◽  
R P Viscidi ◽  
J E Gern ◽  
P A Murphy ◽  
...  
Keyword(s):  
Enzyme Immunoassay ◽  
Messenger Rna ◽  
Quantitative Detection

scholarly journals Molecular diagnosis of Hepatozoon canis in symptomatic dogs in the city of Goiania, Goiás, Brazil

2016 ◽  
Vol 68 (6) ◽  
pp. 1431-1439
Author(s):  
S.C. Duarte ◽  
J.A. Parente ◽  
O.J. Silveira Neto ◽  
V.S. Jayme ◽  
T.S.A. Bastos ◽  
...  
Keyword(s):  
Laboratory Diagnosis ◽  
Extraction Process ◽  
Hepatozoon Canis ◽  
Phylogenetic Study ◽  
Blood Smears ◽  
Two Samples ◽  
Pcr Products ◽  
Hepatozoon Americanum ◽  
The City ◽  
Veterinary Hospital

ABSTRACT More than 300 species have been described in the genus Hepatozoon, occurring in different vertebrates. Among these, only Hepatozoon canis and Hepatozoon americanum are seen in dogs. Different methods may be used for laboratory diagnosis. The most common of these is direct parasitological examination of parasite stages in blood smears. The aim of this investigation was to conduct a phylogenetic study on Hepatozoon isolates from symptomatic dogs in the city of Goiânia, Goiás, Brazil. Blood samples were obtained from 40 symptomatic dogs that had been referred to the Veterinary Hospital of the Federal University of Goiás. Among these, only two samples were positive for Hepatozoon spp. using the direct parasitological method. These samples were then subjected to a DNA extraction process and amplification of a fragment of the 18S rRNA by means of PCR. Subsequently, the PCR products from each sample were purified and sequenced. The sequences obtained were then analyzed using the BLASTn algorithm, which identified both sequences of this study as Hepatozoon canis. By applying the Mega4 software, it was confirmed that these isolates of H. canis from dogs in Goiânia are similar to other reference isolates of the same species from other regions of Brazil and worldwide.

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 Methods for Molecular Surveillance of Influenza Used in Macedonia

PRILOZI ◽  
2014 ◽  
Vol 35 (2) ◽  
pp. 25-30
Author(s):  
Golubinka Bosevska ◽  
Elizabeta Janceska ◽  
Gordana Kuzmanovska ◽  
Vladimir Mikik ◽  
Nikola Panovski
Keyword(s):  
Influenza Virus ◽  
Predictive Value ◽  
Influenza A ◽  
Rna Extraction ◽  
Influenza Virus Infection ◽  
Laboratory Diagnosis ◽  
Influenza Viruses ◽  
Rt Pcr ◽  
Two Samples ◽  
Nose And Throat

AbstractThe aim: To present and compare different Nucleic Acid Testing assays used for laboratory diagnosis of influenza virus infection in our country.Materials and methods: Respiratory samples used were nose and throat swabs. The RNA extraction was performed with a QIAamp viral RNA kit. During the season 2009–2010 the first 25 samples were tested with: conventional gel-based RT-PCR and CDC rtRT-PCR using published specific matrix and HA gene primers and probes for influenza virus typing and subtyping.Results: Of 25 samples tested with conventional RT-PCR7(28%) were positive for influenza A, but negative for A/H1seasonal and A/H3. Retested with rtRT-PCR 9(36%) were positive for influenza A, 8(32%) were positive for A/H1pdm and 1(4%) was A/H3. Two samples positive with rtRT-PCR for influenza A were negative with RT-PCR. The sensitivity of the RT-PCR in comparison with rtRT-PCR is 100% and the specificity is 88.89%. Positive predictive value for RT-PCR is 77.78%, and negative predictive value is 100%. RT-PCR is a four-step and rtRT-PCR a one-step procedure. The turn-around time of RT-PCR is 6 hours and for rtRT-PCR it is 2 hours.Discussion and conclusion: For surveillance purposes nose and throat swabs are the more easy and practical to collect. It was proved that RT-PCR is too laborious, multi-step and time-consuming. The sensitivity of both assays is equal. The specificity of rtRT-PCR is higher. NAT assays for detection of influenza viruses have become an integral component of the surveillance programme in our country. They provide a fast, accurate and sensitive detection of influenza.

Low Rate of False-Positive Results with Use of A Rapid HIV Test

2002 ◽  
Vol 23 (6) ◽  
pp. 335-337 ◽  
Author(s):  
Cassandra D. Salgado ◽  
Heidi L. Flanagan ◽  
Doris M. Haverstick ◽  
Barry M. Farr
Keyword(s):  
Enzyme Immunoassay ◽  
False Positive ◽  
Diagnostic System ◽  
Rapid Test ◽  
Occupational Exposures ◽  
High Rate ◽  
Negative Results ◽  
Hiv Test ◽  
Rapid Hiv Test ◽  
Positive Results

Background:Occupational exposure to human immunodeficiency virus (HIV) is an important threat to healthcare workers. Centers for Disease Control and Prevention guidelines recommend prompt institution of prophylaxis. This requires (1) immediate prophylaxis after exposure, pending test results that may take more than 24 hours in many hospitals; or (2) performance of a rapid test. The Single Use Diagnostic System (SUDS)® HIV-1 Test is used to screen rapidly for antibodies to HIV type 1 in plasma or serum, with a reported sensitivity of more than 99.9%. We used this test from January 1999 until September 2000, when it was withdrawn from the market following reports claiming a high rate of false-positive results.Methods:We reviewed the results of postexposure HIV testing during 21 months.Results:A total of 884 SUDS tests were performed on source patients after occupational exposures (883 negative results, 1 reactive result). The results of repeat SUDS testing on the reactive specimen were also reactive, but the results of enzyme immunoassay and Western blot testing were negative. A new specimen from the same patient showed a negative result on SUDS testing. This suggested a specificity of 99.9%. In the 4 months after SUDS testing was suspended, there was 1 false-positive result on enzyme immunoassay for 1 of 132 source patients (presumed specificity, 99.2%).Conclusion:Use of the SUDS test facilitated rapid and accurate evaluation of source specimens, obviating unnecessary prophylaxis.

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