Serological Diagnostics of Lyme Borreliosis: Comparison of Universal andBorreliaSpecies-Specific Tests Based on Whole-Cell and Recombinant Antigens

ABSTRACTThe study compares diagnostic parameters of different commercial serological kits based on three different antigen types and correlates test results with the status of the patient'sBorreliainfection. In total, 8 IgM and 8 IgG kits were tested, as follows: enzyme-linked immunosorbent assay (ELISA) (Euroimmun) based on whole-cell antigen, 3 species-specific enzyme immunoassays (EIAs) (TestLine), Liaison chemiluminescence (DiaSorin), ELISA-Viditest (Vidia), EIA, and Blot-Line (TestLine) using recombinant antigens. All tests were performed on a panel of 90 samples from patients with clinically characterized borreliosis (53 with neuroborreliosis, 32 with erythema migrans, and 5 with arthritis) plus 70 controls from blood donors and syphilis patients. ELISA based on whole-cell antigens has superior sensitivity and superior negative predictive value and serves as an excellent screening test, although its specificity and positive predictive values are low. Species-specific tests have volatile parameters. Their low sensitivity and low negative predictive value handicap them in routine diagnostics. Tests with recombinant antigens are characterized by high specificity and high positive predictive value and have a wide range of use in diagnostic practice. Diagnostic parameters of individual tests depend on the composition of the sample panel. Only a small proportion of contradictory samples giving both negative and positive results is responsible for discrepancies between test results. Correlation of test results with the patient's clinical state is limited, especially in the erythema migrans group with high proportions of negative and contradictory results. In contrast, IgG test results in the neuroborreliosis group, which are more concordant, show acceptable agreement withBorreliastatus.

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Evaluation of the Carba NP Test for Rapid Detection of Carbapenemase-Producing Enterobacteriaceae and Pseudomonas aeruginosa

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00878-13 ◽

2013 ◽

Vol 57 (9) ◽

pp. 4578-4580 ◽

Cited By ~ 147

Author(s):

Nathalie Tijet ◽

David Boyd ◽

Samir N. Patel ◽

Michael R. Mulvey ◽

Roberto G. Melano

Keyword(s):

Pseudomonas Aeruginosa ◽

Positive Predictive Value ◽

Negative Predictive Value ◽

Predictive Value ◽

Rapid Detection ◽

False Negative ◽

Bacterial Extract ◽

Content Type ◽

Negative Results ◽

False Negative Results

ABSTRACTThe Carba NP test was evaluated against a panel of 244 carbapenemase- and non-carbapenemase-producingEnterobacteriaceaeandPseudomonas aeruginosaisolates. We confirmed the 100% specificity and positive predictive value of the test, but the sensitivity and negative predictive value were 72.5% and 69.2%, respectively, and increased to 80% and 77.3%, respectively, using a more concentrated bacterial extract. False-negative results were associated with mucoid strains or linked to enzymes with low carbapenemase activity, particularly OXA-48-like, which has emerged globally in enterobacteria.

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Repeated Testing Necessary: Assessing Negative Predictive Value of SARS-CoV-2 qPCR in a Population of Young Adults

10.1101/2021.03.10.21253292 ◽

2021 ◽

Author(s):

Elaine E. Thompson ◽

Joseph Rosenthal ◽

James Wren ◽

Erik Seetao ◽

Niels H. Olson

Keyword(s):

Negative Predictive Value ◽

Predictive Value ◽

Test Results ◽

Retrospective Evaluation ◽

Repeated Testing ◽

Aircraft Carrier ◽

Theodore Roosevelt ◽

Community Risk ◽

Community Risk Factors ◽

Test Result

AbstractDetermining when individuals should be released from quarantine is critical for successfully managing a COVID-19 outbreak and local protocols frequently call for testing during the quarantine period, generally after a reasonable incubation period, which raises a question about the interpretation of test results during the quarantine period. We report the negative predictive value of SARS-CoV-2 qPCR tests based on a retrospective longitudinal analysis of 5349 qPCR tests collected from 1227 US service members infected with COVID-19 aboard the USS Theodore Roosevelt (CVN-71) aircraft carrier. In our retrospective evaluation of recovering qPCR-positive quarantined crew members undergoing repeated testing, the negative predictive value is 80% for tests occurring as late as seven weeks following an initial positive qPCR test result. Repeated qPCR testing is necessary to ensure that a once-infected person is no longer shedding viral RNA. When deciding the stringency of exit criteria, we recommend considering local operational and community risk factors.

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Tyrosine-Phosphorylated Ehrlichia chaffeensis and Ehrlichia canis Tandem Repeat Orthologs Contain a Major Continuous Cross-Reactive Antibody Epitope in Lysine-Rich Repeats

Infection and Immunity ◽

10.1128/iai.01347-10 ◽

2011 ◽

Vol 79 (8) ◽

pp. 3178-3187 ◽

Cited By ~ 17

Author(s):

Jere W. McBride ◽

Xiaofeng Zhang ◽

Abdul Wakeel ◽

Jeeba A. Kuriakose

Keyword(s):

Amino Acids ◽

Tandem Repeat ◽

Tandem Repeats ◽

Ehrlichia Canis ◽

Small Subset ◽

Ehrlichia Chaffeensis ◽

Whole Cell ◽

Content Type ◽

Cell Lysates ◽

Species Specific

ABSTRACTA small subset of major immunoreactive proteins have been identified inEhrlichia chaffeensisandEhrlichia canis, including three molecularly and immunologically characterized pairs of immunoreactive tandem repeat protein (TRP) orthologs with major continuous species-specific epitopes within acidic tandem repeats (TR) that stimulate strong antibody responses during infection. In this study, we identified a fourth major immunoreactive TR-containing ortholog pair and defined a major cross-reactive epitope in homologous nonidentical 24-amino-acid lysine-rich TRs. Antibodies from patients and dogs with ehrlichiosis reacted strongly with recombinant TR regions, and epitopes were mapped to the N-terminal TR region (18 amino acids) inE. chaffeensisand the complete TR (24 amino acids) inE. canis. Two less-dominant epitopes were mapped to adjacent glutamate/aspartate-rich and aspartate/tyrosine-rich regions in the acidic C terminus ofE. canisTRP95 but not inE. chaffeensisTRP75. Major immunoreactive proteins inE. chaffeensis(75-kDa) andE. canis(95-kD) whole-cell lysates and supernatants were identified with TR-specific antibodies. Consistent with other ehrlichial TRPs, the TRPs identified in ehrlichial whole-cell lysates and the recombinant proteins migrated abnormally slow electrophoretically a characteristic that was demonstrated with the positively charged TR and negatively charged C-terminal domains.E. chaffeensisTRP75 andE. canisTRP95 were immunoprecipitated with anti-pTyr antibody, demonstrating that they are tyrosine phosphorylated during infection of the host cell.

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Development of an Enzyme-Linked Immunosorbent Assay for Serodiagnosis of Ringworm Infection in Cattle

Clinical and Vaccine Immunology ◽

10.1128/cvi.00243-13 ◽

2013 ◽

Vol 20 (8) ◽

pp. 1150-1154 ◽

Cited By ~ 6

Author(s):

Elena Tatiana Băguţ ◽

Ludivine Cambier ◽

Marie-Pierre Heinen ◽

Vasile Cozma ◽

Michel Monod ◽

...

Keyword(s):

Positive Predictive Value ◽

Negative Predictive Value ◽

Immunosorbent Assay ◽

Predictive Value ◽

Skin Lesions ◽

Enzyme Linked Immunosorbent Assay ◽

Serum Samples ◽

Predictive Values ◽

Content Type ◽

Ringworm Infection

ABSTRACTThe aim of this study was to develop an in-house enzyme-linked immunosorbent assay (ELISA) for the serological diagnosis of ringworm infection in cattle. We used available recombinant forms ofTrichophyton rubrumdipeptidyl peptidase V (TruDppV) andT. rubrumleucin aminopeptidase 2 (TruLap2), which are 98% identical toTrichophyton verrucosumorthologues. Field serum samples from 135 cattle with ringworm infection, as confirmed by direct microscopy, fluorescence microscopy, and PCR, and from 55 cattle without any apparent skin lesions or history of ringworm infection that served as negative controls were used. Sensitivities, specificities, and positive and negative predictive values were determined to evaluate the diagnostic value of our ELISA. Overall, the ELISAs based on recombinant TruDppV and TruLap2 discriminated well between infected animals and healthy controls. Highly significant differences (P< 0.0001, Mann-Whitney U test) were noted between optical density values obtained when sera from infected versus control cattle were tested. The ELISA developed for the detection of specific antibodies against DppV gave 89.6% sensitivity, 92.7% specificity, a 96.8% positive predictive value, and a 78.4% negative predictive value. The recombinant TruLap2-based ELISA displayed 88.1% sensitivity, 90.9% specificity, a 95.9% positive predictive value, and a 75.7% negative predictive value. To the best of our knowledge, this is the first ELISA based on recombinant antigens for assessing immune responses to ringworm infection in cattle; it is particularly suitable for epidemiological studies and also for the evaluation of vaccines and/or vaccination procedures.

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Evaluation of the QiagenartusC. difficile QS-RGQ Kit for Detection of Clostridium difficile Toxins A and B in Clinical Stool Specimens

Journal of Clinical Microbiology ◽

10.1128/jcm.00613-15 ◽

2015 ◽

Vol 53 (6) ◽

pp. 1942-1944 ◽

Cited By ~ 8

Author(s):

Nathalie Jazmati ◽

Pia Wiegel ◽

Božica Ličanin ◽

Georg Plum

Keyword(s):

Nucleic Acid ◽

Clostridium Difficile ◽

Positive Predictive Value ◽

Negative Predictive Value ◽

Predictive Value ◽

Nucleic Acid Amplification Test ◽

Nucleic Acid Amplification ◽

Content Type ◽

Stool Specimens ◽

Sensitivity Specificity

We compared the QiagenartusC. difficile QS-RGQ kit, a new nucleic acid amplification test for the detection ofClostridium difficiletoxins in stool specimens, with the Cepheid XpertC. difficiletest. The sensitivity, specificity, positive predictive value, and negative predictive value for the QiagenartusC. difficile QS-RGQ test were 100%, 89.5%, 60.9%, and 100%, and those for the Cepheid XpertC. difficiletest were 100%, 90%, 62.2%, and 100%, respectively.

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Retrospective Review ofTreponema pallidumPCR and Serology Results: Are Both Tests Necessary?

Journal of Clinical Microbiology ◽

10.1128/jcm.01782-17 ◽

2018 ◽

Vol 56 (5) ◽

Cited By ~ 6

Author(s):

Anna Brischetto ◽

Ian Gassiep ◽

David Whiley ◽

Robert Norton

Keyword(s):

Positive Predictive Value ◽

Negative Predictive Value ◽

Predictive Value ◽

Treponema Pallidum ◽

Clinical Value ◽

Herpes Simplex Virus 1 ◽

Content Type ◽

Retrospective Audit ◽

Simplex Virus ◽

Syphilis Serology

ABSTRACTThere has been a resurgence of syphilis diagnoses in Australia. We investigated whether ourTreponema pallidumPCR test provides any additional diagnostic information over syphilis serology (chemiluminescence immunoassay [CMIA],Treponema pallidumparticle agglutination [TPPA] assay, and the rapid plasma reagin [RPR] flocculation test). A retrospective audit of allT. pallidumPCR requests that came through our laboratory from January 2010 to June 2017 was conducted; data collected included age, gender, site of swab, and results fromT. pallidumPCR, syphilis serology, and herpes simplex virus 1 (HSV-1) and HSV-2 PCRs. A total of 441T. pallidumPCR tests were performed; on average, 3T. pallidumPCRs per month were requested in 2011, and this rate increased to 17.2 requests per month in 2017. A total of 323 patients had bothT. pallidumPCR and syphilis serology performed, with 67% of swabs taken from the genitals.T. pallidumPCR gave positive results for 61/323 (19%) patients; of these 61 patients, 59 (97%) also had positive syphilis serology results (T. pallidumPCR sensitivity, 68%; specificity, 99%; positive predictive value, 97%; negative predictive value, 89%). Syphilis serology was positive for 91/323 patients (28%); of these 91 patients, 61 (66%) were alsoT. pallidumPCR positive (syphilis serology sensitivity, 97%; specificity, 88%; positive predictive value, 60%; negative predictive value, 99%). The Cohen's kappa value was 0.74, indicating substantial agreement between the two tests. Our results show that most patients with positiveT. pallidumPCR results also had positive syphilis serology. Therefore,T. pallidumPCR adds little clinical value over serology for the diagnosis of syphilis in certain clinical settings.

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Comparison of GenomEra C. difficile and Xpert C. difficile as Confirmatory Tests in a Multistep Algorithm for Diagnosis of Clostridium difficile Infection

Journal of Clinical Microbiology ◽

10.1128/jcm.03093-14 ◽

2014 ◽

Vol 53 (1) ◽

pp. 332-335 ◽

Cited By ~ 11

Author(s):

Luis Alcalá ◽

Elena Reigadas ◽

Mercedes Marín ◽

Antonia Fernández-Chico ◽

Pilar Catalán ◽

...

Keyword(s):

Clostridium Difficile ◽

Positive Predictive Value ◽

Negative Predictive Value ◽

Clostridium Difficile Infection ◽

Predictive Value ◽

Confirmatory Test ◽

Content Type ◽

Diagnostic Algorithms ◽

Confirmatory Tests ◽

Sensitivity Specificity

We compared two multistep diagnostic algorithms based on C. Diff Quik Chek Complete and, as confirmatory tests, GenomEraC. difficileand XpertC. difficile. The sensitivity, specificity, positive predictive value, and negative predictive value were 87.2%, 99.7%, 97.1%, and 98.3%, respectively, for the GenomEra-based algorithm and 89.7%, 99.4%, 95.5%, and 98.6%, respectively, for the Xpert-based algorithm. GenomEra represents an alternative to Xpert as a confirmatory test of a multistep algorithm forClostridium difficileinfection (CDI) diagnosis.

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Use of the nine-step inflation/deflation test and resting middle-ear pressure range as predictors of middle-ear barotrauma in aircrew members

The Journal of Laryngology & Otology ◽

10.1017/s0022215114001467 ◽

2014 ◽

Vol 128 (7) ◽

pp. 612-617 ◽

Cited By ~ 7

Author(s):

A Hussein ◽

A Abousetta

Keyword(s):

Negative Predictive Value ◽

Middle Ear ◽

Predictive Value ◽

Pressure Range ◽

Test Results ◽

Randomised Study ◽

Middle Ear Pressure ◽

Group A ◽

Group B

AbstractObjective:To explore the role of the nine-step inflation/deflation tympanometric test and resting middle-ear pressure range as predictors of barotrauma in aircrew members.Methods:A prospective, non-randomised study was conducted on 100 aircrew members. Resting middle-ear pressure was measured and the nine-step inflation/deflation test performed on all subjects before flights. Subjects were allocated to two groups according to resting middle-ear pressure range (group A, within the range of +26 to +100 and −26 to −100 mmH2O; group B, −25 to +25 mmH2O). All aircrew members were assessed after flights regarding the presence and the grade of barotrauma.Results:In both groups, the sensitivity and specificity values of the entire post-inflation/deflation test were close to those of the post-deflation part of the test. The post-deflation test had a higher negative predictive value than the post-inflation test. Ears with resting middle-ear pressure lower than −55 mmH2O experienced barotrauma, regardless of good or poor post-inflation or post-deflation test results.Conclusion:In an aircrew member, a resting middle-ear pressure within the range of −55 and +50 mmH2O, together with good post-deflation test results, are considered reliable predictors for fitness to fly.

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Diagnosis of Newly Delivered Mothers for Periodontitis with a Novel Oral-Rinse aMMP-8 Point-of-Care Test in a Rural Malawian Population

Diagnostics ◽

10.3390/diagnostics8030067 ◽

2018 ◽

Vol 8 (3) ◽

pp. 67 ◽

Cited By ~ 14

Author(s):

Jussi Leppilahti ◽

Ulla Harjunmaa ◽

Jorma Järnstedt ◽

Charles Mangani ◽

Marcela Hernández ◽

...

Keyword(s):

Bone Loss ◽

Negative Predictive Value ◽

Likelihood Ratio ◽

Predictive Value ◽

Point Of Care ◽

Test Results ◽

Oral Rinse ◽

Point Of Care Test ◽

Statistical Measures ◽

Sampling Procedures

A novel qualitative point-of-care test of activated matrix metalloproteinase-8 (aMMP-8) using noninvasive oral rinse sampling procedures has been developed for the early detection of collagen breakdown indicating periodontal tissue destruction. The main object of this study was to assess the reliability of the test in a low-income setting to identify participants with history of periodontal destruction detected as alveolar bone loss (ABL) in radiographs. This cross-sectional study included 486 women who had recently delivered in rural Malawi. The aMMP-8 test and dental panoramic radiographs were taken within 48 h of delivery. The performance of the test in comparison to radiological examinations was tested by following the standards for reporting of diagnostic accuracy studies protocol (STARD) with respective statistical measures and 95% confidence intervals. From the 486 eligible participants, 461 mothers with complete data, aged from 15 to 46 years (mean 24.8, SD 6.0) were included in the analysis. ABL was identified in 116 of 461 participants. There was 56% agreement between the aMMP-8 test results and detected ABL (yes or no) in radiographs. Calculated sensitivity of the test was 80% (72–87%), specificity 48% (43–54%), positive predictive value 34% (31–37%), negative predictive value 88% (83–91%), positive likelihood ratio 1.55 (1.35–1.77), and negative likelihood ratio 0.41(0.28–0.60). The aMMP-8 test sensitivity and negative predictive value to identify the ABL cases were relatively high, but there was additionally a high rate of test-positive results in participants without ABL, especially in young mothers, leading to low overall agreement between the test results and radiological bone loss. Further longitudinal studies are needed to examine if the test positive subjects are in risk of future bone loss before the detectable signs of periodontitis in radiographs.

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Evaluation of Wondfo Chlamydia Trachomatis Rapid Diagnostic Cassette Based on Nano-Gold Immunochromatography Gssay（GICA）

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.236-238.2436 ◽

2011 ◽

Vol 236-238 ◽

pp. 2436-2440

Author(s):

Yun Ping Peng ◽

Ji Hua Wang ◽

Wen Mei Li ◽

Jun Lin Wu ◽

Shu Juan Yu

Keyword(s):

Chlamydia Trachomatis ◽

Positive Predictive Value ◽

Negative Predictive Value ◽

Sensitivity And Specificity ◽

Predictive Value ◽

Surveillance Data ◽

Blind Detection ◽

Test Results ◽

Nano Gold ◽

Sensitivity Specificity

This paper explains and demonstrates how to evaluate the sensitivity and specificity of wondfo chlamydia trachomatis rapid diagnostic cassette with GICA for detection of chlamydia trachomatis. 1026 genital specimens were collected from 630 females and 396 males.Two cassettes of wondfo and ClearView were used for the detection of Chlamydia trachomatis samples with blind detection simultaneously, inconsistent results by DFA. Sensitivity, specificity, positive predictive value and negative predictive value of wondfo cassette were analyzed. Out of 1026 samples detected, 83 were positive by both of wondfo and ClearView and 13 showed different results by wondfo and ClearView. Out of the 13 samples, the DFA confirmed 9 were positive. Therefore, 92 samples were truly positive and 934 were truly negative. The sensitivity, specificity, positive predictive value and negative predictive value of wondfo were 96.74% ,99.6% , 95.7% , 99.68%, respectively. The consistent rates of test results of the chlamydia trachomatis rapid diagnostic cassette , wondfo and ClearView, both were the same 98.64%. Of the three standard strains and two clinical strains of dilution test results showed that the sensitivity of wondfo slightly ClearView.The sensitivity and specificity of wondfo for the detection of Chlamydia trachomatis have the accept tability for clinical diagnostic and surveillance data.

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