New Latex Bead Agglutination Assay for Differential Diagnosis of Cattle Infected with Mycobacterium bovis and Mycobacterium avium subsp. paratuberculosis

ABSTRACT Extensive studies have shown that the current assays used to identify cattle infected with Mycobacterium bovis or Mycobacterium avium subsp. paratuberculosis are not sufficiently sensitive and specific to detect all infected animals, especially animals recently infected with the pathogens. In the present report we show that these limitations might be overcome with a latex bead agglutination assay (LBAA). With the specific immunodominant epitope (ESAT6-p) of M. bovis, we developed an LBAA and enzyme immunoassay (EIA) for that purpose and compared them with the “gold standard” culture method and skin test for their efficacy in detecting bovine tuberculosis. When sera from control healthy cows (n = 10), M. avium subsp. paratuberculosis-positive cattle (naturally infected, n = 16; experimentally infected, n = 8), and M. bovis-positive cattle (naturally infected, n = 49;experimentally infected, n = 20) were applied to an EIA and an LBAA developed with ESAT6-p, the two tests showed similar sensitivity (97.1% by EIA, 95.7% by LBAA), high specificity (94.2% by EIA, 100% by LBAA), and a positive correlation (kappa value, 0.85; correlation rate, 93.2%; correlation coefficient, 0.64). Receiver operating characteristic analysis of EIA results and comparison with the culture method determined a suitable cutoff value at 0.469, with an area under the curve of 0.991 (95% confidence interval, 0.977 to 1.0). As LBAA didn't show any positive reactions with sera from uninfected control cows or M. avium subsp. paratuberculosis-infected cattle, which were confirmed to be free of M. bovis by culture or PCR, LBAA using the ESAT6-p can be a rapid and useful M. bovis diagnostic assay. The data suggest that rapid, sensitive, and specific assays can be developed with peptides containing immunodominant epitopes present in proteins uniquely expressed in M. bovis or M. avium subsp. paratuberculosis for differential diagnosis of cattle infected with M. bovis or M. avium subsp. paratuberculosis.

Download Full-text

Evaluation of the automated LIAISON® SARS-CoV-2 TrimericS IgG assay for the detection of circulating antibodies

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2021-0023 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Fabrizio Bonelli ◽

Frank A. Blocki ◽

Tina Bunnell ◽

Edward Chu ◽

Arriel De La O ◽

...

Keyword(s):

New York ◽

New Mexico ◽

Vaccine Development ◽

False Negative ◽

Area Under The Curve ◽

High Specificity ◽

Epidemiological Studies ◽

Youden Index ◽

Characteristic Analysis ◽

Highly Sensitive

Abstract Objectives COVID-19 has brought about tests from many manufacturers. While molecular and rapid antigen tests are targeted for early diagnosis, immunoassays have a larger role in epidemiological studies, understanding longitudinal immunity, and in vaccine development and response. Methods The performance of the LIAISON® SARS-CoV-2 TrimericS IgG assay was evaluated against the Beckman ACCESS SARS-CoV-2 IgG assay in New Mexico, and against the Siemens ADVIA Centaur COV2G assay in New York. Discordant samples were parsed using a microneutralization assay. Results A SARS-CoV-2 antibody positivity rate of 23.8% was observed in the samples tested in New York (September 2020), while in the same month the positivity rate was 1.5% in New Mexico. Positive and negative agreement were 67.6% (95% CI 49.5–82.6%) and 99.8% (95% CI 99.5–99.9%), respectively, with the Beckman test, and 98.0% (95% CI 95.7–99.3%) and 94.8% (95% CI 93.4–96.0%), respectively, with the Siemens test. Receiver operating characteristic analysis for the detection of SARS-CoV-2 antibodies discloses an AUC, area under the curve, of 0.996 (95% CI 0.992–0.999) for the LIAISON® SARS-CoV-2 TrimericS IgG assay. The criterion associated to the Youden Index was determined to be >12.9 kAU/L with a sensitivity of 99.44% and a specificity of 99.82%. Conclusions The LIAISON® SARS-CoV-2 TrimericS IgG assay is highly sensitive and specific. The balance of these parameters, without emphasis on high specificity alone, is particularly important when applied to high prevalence populations, where a highly sensitive assay will result in reporting a lower number of false negative subjects.

Download Full-text

Comparison of CSF and serum neurofilament light and heavy chain as differential diagnostic biomarkers for ALS

Journal of Neurology Neurosurgery & Psychiatry ◽

10.1136/jnnp-2021-327129 ◽

2021 ◽

pp. jnnp-2021-327129

Author(s):

Steffen Halbgebauer ◽

Petra Steinacker ◽

Federico Verde ◽

Jochen Weishaupt ◽

Patrick Oeckl ◽

...

Keyword(s):

Differential Diagnosis ◽

Area Under The Curve ◽

Characteristic Analysis ◽

Neurofilament Light ◽

Diagnostic Biomarkers ◽

Diagnostic Potential ◽

Jakob Disease ◽

Auc Value ◽

The Difference ◽

Lateral Sclerosis

ObjectiveElevated levels of neurofilament light (NfL) and heavy (NfH) chain in amyotrophic lateral sclerosis (ALS) cerebrospinal fluid (CSF) and serum reflect neuro-axonal degeneration and are used as diagnostic biomarkers. However, studies comparing the differential diagnostic potential for ALS of all four parameters are missing. Here, we measured serum NfL/NfH and CSF NfL/NfH in a large cohort of ALS and other neurological disorders and analysed the differential diagnostic potential.MethodsIn total CSF and serum of 294 patients were analysed. The diagnostic groups comprised: ALS (n=75), frontotemporal lobar degeneration (FTLD) (n=33), Alzheimer’s disease (n=20), Parkinson’s disease (dementia) (n=18), Creutzfeldt-Jakob disease (n=11), non-neurodegenerative controls (n=77) (Con) and 60 patients who were seen under the direct differential diagnosis of a patient with ALS (Con.DD).ResultsCSF and serum NfL and NfH showed significantly increased levels in ALS (p<0.0001) compared with Con and Con.DD. The difference between ALS and FTLD was markedly stronger for NfH than for NfL. CSF and serum NfL demonstrated a stronger correlation (r=0.84 (95% CI 0.80 to 0.87), p<0.001) than CSF and serum NfH (r=0.68 (95% CI 0.61 to 0.75), p<0.0001). Comparing ALS and Con.DD, receiver operating characteristic analysis revealed the best area under the curve (AUC) value for CSF NfL (AUC=0.94, 95% CI 0.91 to 0.98), followed by CSF NfH (0.93, 95% CI 0.88 to 0.98), serum NfL (0.93, 95% CI 0.89 to 0.97) and serum NfH (0.88, 95% CI 0.82 to 0.94).ConclusionOur results demonstrate that CSF NfL and NfH as well as serum NfL are equally suited for the differential diagnosis of ALS, whereas serum NfH appears to be slightly less potent.

Download Full-text

Diagnosis of Bovine Paratuberculosis by a Novel Enzyme-Linked Immunosorbent Assay Based on Early Secreted Antigens of Mycobacterium avium subsp. paratuberculosis

Clinical and Vaccine Immunology ◽

10.1128/cvi.00105-08 ◽

2008 ◽

Vol 15 (8) ◽

pp. 1277-1281 ◽

Cited By ~ 31

Author(s):

Sung Jae Shin ◽

Donghee Cho ◽

Michael T. Collins

Keyword(s):

Immunosorbent Assay ◽

Mycobacterium Avium ◽

Area Under The Curve ◽

Cost Effective ◽

Enzyme Linked Immunosorbent Assay ◽

Protein Antigens ◽

Characteristic Analysis ◽

Mycobacterium Avium Subsp Paratuberculosis ◽

Cattle Herds ◽

Low Passage

ABSTRACT We previously reported that protein antigens of serodiagnostic potential were more abundant in culture filtrates than cellular extracts from liquid cultures of Mycobacterium avium subsp. paratuberculosis (D. Cho and M. T. Collins, Clin. Vaccine Immunol. 13:1155-1161, 2006). Based on this observation, a novel enzyme-linked immunosorbent assay (ELISA) using antigens secreted by young (early- to mid-log-phase) cultures of M. avium subsp. paratuberculosis JTC303 (a low-passage isolate originating from the ileum of a Holstein bull) in mycobactin-supplemented Watson-Reid medium (pH 6.0) was developed and evaluated using a previously described panel of bovine sera (M. T. Collins et al., Clin. Diagn. Lab. Immunol. 12:685-692, 2005) that included 444 paratuberculosis cases and 412 controls. The new assay, called JTC-ELISA, had a significantly higher diagnostic sensitivity and an equivalent specificity compared to those of five commercial paratuberculosis ELISA kits. By receiver-operating characteristic analysis, the JTC-ELISA had the highest area under the curve of the six assays evaluated. The JTC-ELISA was particularly sensitive at detecting low-level fecal shedders of Mavium subsp. paratuberculosis (40%; the sensitivity of the commercial kits was 20%). The JTC-ELISA works effectively on both serum and milk samples for the detection of cattle with subclinical M. avium subsp. paratuberculosis infections, providing a cost-effective diagnostic tool to support paratuberculosis control programs in cattle herds.

Download Full-text

Isolation of Mycobacterium avium Subsp. Paratuberculosis in the Feces and Tissue of Small Ruminants Using a Non-Automated Liquid Culture Method

Animals ◽

10.3390/ani10010020 ◽

2019 ◽

Vol 10 (1) ◽

pp. 20

Author(s):

Luigi De Grossi ◽

Davide Santori ◽

Antonino Barone ◽

Silvia Abbruzzese ◽

Matteo Ricchi ◽

...

Keyword(s):

Mycobacterium Avium ◽

Liquid Culture ◽

Culture Media ◽

Small Ruminants ◽

Culture Method ◽

Mycobacterium Avium Subsp ◽

Type I ◽

Culture Methods ◽

Specific Pcr ◽

Mycobacterium Avium Subsp Paratuberculosis

Paratuberculosis is a chronic disease of ruminants caused by Mycobacterium avium subsp. Paratuberculosis (MAP). Since isolation of MAP type I (S) is rarely reported in Italy, our research was aimed at isolating, by an inexpensive liquid culture manual method, this type of MAP isolates. At first, we used an ELISA to point out to serologically positive samples from five flocks. Secondly, we used a fecal direct IS900-qPCR on the ELISA positive samples, in order to detect shedder animals. Feces from IS900-qPCR positive samples were inoculated in solid and liquid culture media. IS900-qPCR was further used to test the growth of MAP isolates in liquid medium, which were further confirmed by f57-qPCR and submitted to typing by specific PCR in order to identify the MAP type. Twenty-eight samples (24 fecal and four tissutal samples) were processed by culture methods, resulting in the isolation of six type I MAP field isolates. Notably, no isolates were recovered by solid media, underlining the utility of this liquid method. Few data about this type of MAP are currently available in Italy, and further analyses should be carried out in order to study the origin and epidemiology of type I strains circulating in Italy.

Download Full-text

Measles Virus IgG Avidity Assay for Use in Classification of Measles Vaccine Failure in Measles Elimination Settings

Clinical and Vaccine Immunology ◽

10.1128/cvi.00406-12 ◽

2012 ◽

Vol 19 (11) ◽

pp. 1810-1817 ◽

Cited By ~ 38

Author(s):

Sara Mercader ◽

Philip Garcia ◽

William J. Bellini

Keyword(s):

Measles Virus ◽

Area Under The Curve ◽

Epidemiological Data ◽

Diagnostic Tools ◽

High Avidity ◽

Characteristic Analysis ◽

Vaccine Failure ◽

Avidity Assay ◽

Igg Avidity

ABSTRACTIn regions where endemic measles virus has been eliminated, diagnostic assays are needed to assist in correctly classifying measles cases irrespective of vaccination status. A measles IgG avidity assay was configured using a commercially available measles-specific IgG enzyme immunoassay by modifying the protocol to include three 5-min washes with diethylamine (60 mM; pH 10.25) following serum incubation; serum was serially diluted, and the results were expressed as the end titer avidity index. Receiver operating characteristic analysis was used for evaluation and validation and to establish low (≤30%) and high (≥70%) end titer avidity thresholds. Analysis of 319 serum specimens expected to contain either high- or low-avidity antibodies according to clinical and epidemiological data indicated that the assay is highly accurate, with an area under the curve of 0.998 (95% confidence interval [CI], 0.978 to 1.000), sensitivity of 91.9% (95% CI, 83.2% to 97.0%), and specificity of 98.4% (95% CI, 91.6% to 100%). The assay is rapid (<2 h) and precise (standard deviation [SD], 4% to 7%). In 18 samples from an elimination setting outbreak, the assay identified 2 acute measles cases with low-avidity results; both were IgM-positive samples. Additionally, 11 patients (15 samples) with modified measles who were found to have high-avidity IgG results were classified as secondary vaccine failures; one sample with an intermediate-avidity result was not interpretable. In elimination settings, measles IgG avidity assays can complement existing diagnostic tools in confirming unvaccinated acute cases and, in conjunction with adequate clinical and epidemiologic investigation, aid in the classification of vaccine failure cases.

Download Full-text

Head-to-Head Comparison of Two Nomograms Predicting Probability of Lymph Node Invasion in Prostate Cancer and the Therapeutic Impact of Higher Nomogram Threshold

Journal of Clinical Medicine ◽

10.3390/jcm10050999 ◽

2021 ◽

Vol 10 (5) ◽

pp. 999

Author(s):

Zilvinas Venclovas ◽

Tim Muilwijk ◽

Aivaras J. Matjosaitis ◽

Mindaugas Jievaltas ◽

Steven Joniau ◽

...

Keyword(s):

Prostate Cancer ◽

Lymph Node ◽

Area Under The Curve ◽

Pelvic Lymph Node ◽

Cancer Center ◽

Study Cohort ◽

Net Benefit ◽

Characteristic Analysis ◽

Therapeutic Impact ◽

Mskcc Nomogram

Introduction: The aim of the study was to compare the performance of the 2012 Briganti and Memorial Sloan Kettering Cancer Center (MSKCC) nomograms as a predictor for pelvic lymph node invasion (LNI) in men who underwent radical prostatectomy (RP) with pelvic lymph node dissection (PLND), to examine their performance and to analyse the therapeutic impact of using 7% nomogram cut-off. Materials and Methods: The study cohort consisted of 807 men with clinically localised prostate cancer (PCa) who underwent open RP with PLND between 2001 and 2019. The area under the curve (AUC) of the receiver operator characteristic analysis was used to quantify the accuracy of the 2012 Briganti and MSKCC nomograms to predict LNI. Calibration plots were used to visualise over or underestimation by the models and a decision curve analysis (DCA) was performed to evaluate the net benefit associated with the used nomograms. Results: A total of 97 of 807 patients had LNI (12%). The AUC of 2012 Briganti and MSKCC nomogram was 80.6 and 79.2, respectively. For the Briganti nomogram using the cut-off value of 7% would lead to reduce PLND in 47% (379/807), while missing 3.96% (15/379) cases with LNI. For the MSKCC nomogram using the cut-off value of 7% a PLND would be omitted in 44.5% (359/807), while missing 3.62% (13/359) of cases with LNI. Conclusions: Both analysed nomograms demonstrated high accuracy for prediction of LNI. Using a 7% nomogram cut-off would allow the avoidance up to 47% of PLNDs, while missing less than 4% of patients with LNI.

Download Full-text

Red cell distribution width as a predictor for bronchopulmonary dysplasia in premature infants

Scientific Reports ◽

10.1038/s41598-021-86752-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hayato Go ◽

Hitoshi Ohto ◽

Kenneth E. Nollet ◽

Kenichi Sato ◽

Hirotaka Ichikawa ◽

...

Keyword(s):

Blood Cell ◽

Bronchopulmonary Dysplasia ◽

Gestational Age ◽

Red Blood Cell ◽

Area Under The Curve ◽

Cell Distribution ◽

Characteristic Analysis ◽

Distribution Width ◽

Potential Biomarker ◽

Rbc Transfusion

AbstractBronchopulmonary dysplasia (BPD) is the most common morbidity complicating preterm birth. Red blood cell distribution width (RDW), a measure of the variation red blood cell size, could reflect oxidative stress and chronic inflammation in many diseases such as cardiovascular, pulmonary, and other diseases. The objectives of the present study were to evaluate perinatal factors affecting RDW and to validate whether RDW could be a potential biomarker for BPD. A total of 176 preterm infants born at < 30 weeks were included in this study. They were categorized into BPD (n = 85) and non-BPD (n = 91) infants. RDW at birth and 14 days and 28 days of life (DOL 14, DOL 28) were measured. Clinical data were obtained from all subjects at Fukushima Medical University (Fukushima, Japan). The mean RDW at birth, DOL 14 and DOL 28 were 16.1%, 18.6%, 20.1%, respectively. Small for gestational age (SGA), chorioamnionitis (CAM), hypertensive disorders of pregnancy (HDP), gestational age and birth weight were significantly associated with RDW at birth. SGA, BPD and red blood cell (RBC) transfusion before DOL 14 were associated with RDW at DOL 14. BPD and RBC transfusion before DOL 14 were associated with RDW at DOL 28. Compared with non-BPD infants, mean RDW at birth DOL 14 (21.1% vs. 17.6%, P < 0.001) and DOL 28 (22.2% vs. 18.2%, P < 0.001) were significantly higher in BPD infants. Multivariate analysis revealed that RDW at DOL 28 was significantly higher in BPD infants (P = 0.001, odds ratio 1.63; 95% CI 1.22–2.19). Receiver operating characteristic analysis for RDW at DOL 28 in infants with and without BPD yielded an area under the curve of 0.87 (95% CI 0.78–0.91, P < 0.001). RDW at DOL 28 with mild BPD (18.3% vs. 21.2%, P < 0.001), moderate BPD (18.3% vs. 21.2%, P < 0.001), and severe BPD (18.3% vs. 23.9%, P < 0.001) were significantly higher than those with non-BPD, respectively. Furthermore, there are significant differences of RDW at DOL 28 between mild, moderate, and severe BPD. In summary, we conclude that RDW at DOL 28 could serve as a biomarker for predicting BPD and its severity. The mechanism by which RDW at DOL 28 is associated with the pathogenesis of BPD needs further elucidation.

Download Full-text

Value of radiomics in differential diagnosis of chromophobe renal cell carcinoma and renal oncocytoma

Abdominal Radiology ◽

10.1007/s00261-019-02269-9 ◽

2019 ◽

Vol 45 (10) ◽

pp. 3193-3201 ◽

Cited By ~ 3

Author(s):

Yajuan Li ◽

Xialing Huang ◽

Yuwei Xia ◽

Liling Long

Keyword(s):

Machine Learning ◽

Differential Diagnosis ◽

Cell Carcinoma ◽

Area Under The Curve ◽

Image Features ◽

Renal Tumors ◽

Support Vector ◽

Svm Classifier ◽

Renal Oncocytoma ◽

Lasso Regression

Abstract Purpose To explore the value of CT-enhanced quantitative features combined with machine learning for differential diagnosis of renal chromophobe cell carcinoma (chRCC) and renal oncocytoma (RO). Methods Sixty-one cases of renal tumors (chRCC = 44; RO = 17) that were pathologically confirmed at our hospital between 2008 and 2018 were retrospectively analyzed. All patients had undergone preoperative enhanced CT scans including the corticomedullary (CMP), nephrographic (NP), and excretory phases (EP) of contrast enhancement. Volumes of interest (VOIs), including lesions on the images, were manually delineated using the RadCloud platform. A LASSO regression algorithm was used to screen the image features extracted from all VOIs. Five machine learning classifications were trained to distinguish chRCC from RO by using a fivefold cross-validation strategy. The performance of the classifier was mainly evaluated by areas under the receiver operating characteristic (ROC) curve and accuracy. Results In total, 1029 features were extracted from CMP, NP, and EP. The LASSO regression algorithm was used to screen out the four, four, and six best features, respectively, and eight features were selected when CMP and NP were combined. All five classifiers had good diagnostic performance, with area under the curve (AUC) values greater than 0.850, and support vector machine (SVM) classifier showed a diagnostic accuracy of 0.945 (AUC 0.964 ± 0.054; sensitivity 0.999; specificity 0.800), showing the best performance. Conclusions Accurate preoperative differential diagnosis of chRCC and RO can be facilitated by a combination of CT-enhanced quantitative features and machine learning.

Download Full-text

Novel molecular transport medium used in combination with Xpert MTB/RIF ultra provides rapid detection of Mycobacterium bovis in African buffaloes

Scientific Reports ◽

10.1038/s41598-021-86682-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Charlene Clarke ◽

Katrin Smith ◽

Samantha J. Goldswain ◽

Christopher Helm ◽

David V. Cooper ◽

...

Keyword(s):

Mycobacterium Bovis ◽

Human Health Risk ◽

Molecular Transport ◽

Sampling Technique ◽

High Specificity ◽

Negative Control ◽

Post Mortem ◽

Tissue Samples ◽

Transport Medium ◽

Tissue Homogenates

AbstractMycobacterium bovis is the causative agent of bovine tuberculosis (bTB) in wildlife. Confirmation of M. bovis infection relies on mycobacterial culture, which is time-consuming. Collection and transportation of infectious material also pose a human health risk. PrimeStore Molecular Transport Medium (MTM) has been shown to effectively inactivate infectious organisms, making it a safe method for handling infectious samples. This study investigated an in-field sampling technique for rapid, safe detection of M. bovis in buffalo tissues. Potentially infected tissues from bTB test-positive buffaloes were swabbed at post-mortem examination and stored in PrimeStore MTM at ambient temperature until Xpert MTB/RIF Ultra testing was performed. Additionally, tissue samples were frozen and transported before homogenisation for culture and Ultra testing. Oral swabs were collected from M. bovis-unexposed buffaloes as a negative control cohort. Mycobacterium tuberculosis complex (MTBC) DNA was detected by Ultra in 13/16 tissue swabs and 9/16 matched tissue homogenates from culture-confirmed M. bovis-positive buffalo tissues. MTBC DNA was not detected in swabs from M. bovis-unexposed animals, showing the potentially high specificity of Ultra with PrimeStore swabs. PrimeStore MTM sample processing, in combination with the Ultra assay, has the potential to provide a safe, rapid post-mortem screening test for M. bovis in buffaloes.

Download Full-text

Identification of an optimal prolactin threshold to determine prolactinoma size using receiver operating characteristic analysis

Scientific Reports ◽

10.1038/s41598-021-89256-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Bianca M. Leca ◽

Maria Mytilinaiou ◽

Marina Tsoli ◽

Andreea Epure ◽

Simon J. B. Aylwin ◽

...

Keyword(s):

Receiver Operating Characteristic ◽

Operating Characteristic ◽

Tumour Size ◽

Area Under The Curve ◽

Serum Prolactin ◽

Pituitary Neoplasms ◽

Characteristic Analysis ◽

Roc Curve Analysis ◽

Baseline Serum ◽

Receiver Operating

AbstractProlactinomas represent the most common type of secretory pituitary neoplasms, with a therapeutic management that varies considerably based on tumour size and degree of hyperprolactinemia. The aim of the current study was to evaluate the relationship between serum prolactin (PRL) concentrations and prolactinoma size, and to determine a cut-off PRL value that could differentiate micro- from macro-prolactinomas. A retrospective cohort study of 114 patients diagnosed with prolactinomas between 2007 and 2017 was conducted. All patients underwent gadolinium enhanced pituitary MRI and receiver operating characteristic (ROC) analyses were performed. 51.8% of patients in this study were men, with a mean age at the time of diagnosis of 42.32 ± 15.04 years. 48.2% of the total cohort were found to have microadenomas. Baseline serum PRL concentrations were strongly correlated to tumour dimension (r = 0.750, p = 0.001). When performing the ROC curve analysis, the area under the curve was 0.976, indicating an excellent accuracy of the diagnostic method. For a value of 204 μg/L (4338 mU/L), sensitivity and specificity were calculated at 0.932 and 0.891, respectively. When a cut off value of 204 μg/L (4338 mU/L) was used, specificity was 93.2%, and sensitivity 89.1%, acceptable to reliably differentiate between micro- and macro- adenomas.

Download Full-text