scholarly journals Can the Wondfo® SARS-CoV-2 IgM/IgG antibodies be used as a rapid diagnostic test?

2020 ◽  
Vol 4 (1) ◽  
pp. 013-017
Author(s):  
Borges Lysandro Pinto ◽  
De Oliveira Makson Gleydson Brito ◽  
de Souza Daniela Raguer Valadão ◽  
Dos Santos Kezia Alves ◽  
Heimfarth Luana
Keyword(s):  
Predictive Value ◽  
False Negative ◽  
Rapid Test ◽  
Epidemiological Data ◽  
Good Alternative ◽  
Positive Sample ◽  
Igg Antibodies ◽  
Fluorescence Immunoassay ◽  
Negative Results ◽  
Positive Specimen

Background: An outbreak of novel coronavirus (SARS-CoV-2) disease (COVID-19) has rapidly spread worldwide. The aim of this study was to evaluate and validate the performance of the Wondfo® lateral-flow immunochromatographic assay that detect SARS-CoV-2- IgG, IgM antibodies (Wondfo® IC), using the results obtained by the fluorescence immunoassay test as reference diagnostic. Material and methods: 97 serum specimens collected and analyzed by four independent laboratories of Sergipe/Brazil was used for validated the Wondfo® SARS-CoV-2 IgM/IgG antibodies test. The COVID-19 positive serum specimens were determined by fluorescence immunoassay technique, used as reference standard. Results: An overall of 97 serum specimens show 39 (39/97) SARS-CoV-2 IgG positive specimens, 33 (33/97) SARS-CoV-2 IgM positive specimen and 25 non-reagent specimens (25/97). However, the Wondfo® IC assay detected only 9 (9/97) IgM/IgG positive specimen and 25 (25/97) no-reagent specimen. A weak correlation was found between the outcomes of the Wondfo® IC assay and fluorescence test. The accuracy between the two tests was 32.08%. The sensitivity, specificity, positive predictive value, and negative predictive value of Wondfo® IC assay were of 11.12%, 100%, 100% and 25.27%, respectively. Moreover, no false positive sample was determinate, whereas 88.89% of false negative results were found. Conclusion: The Wondfo® IC test failed in providing a quick, valid, and reliable results and appears not to be a good alternative for clinical use in detecting pandemic coronavirus. However, if the limitations of the rapid test are known, some correction factors can be used in order to adjust the epidemiological data.

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

2013 ◽  
Vol 57 (9) ◽  
pp. 4578-4580 ◽  
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.

Evaluation of a Rapid Immunochromatographic test kit to the Gold Standard Fluorescent Antibody test for diagnosis of rabies in animals in Bhutan 

2020 ◽  
Author(s):  
Tenzin Tenzin ◽  
Kelzang Lhamo ◽  
Purna B Rai ◽  
Dawa Tshering ◽  
Pema Jamtsho ◽  
...  
Keyword(s):  
Predictive Value ◽  
Fluorescent Antibody ◽  
False Negative ◽  
Rapid Test ◽  
Antibody Test ◽  
Reference Standard ◽  
Predictive Values ◽  
Percent Agreement ◽  
Test Kit ◽  
Resource Poor

Abstract Background: Rabies kills approximately 59,000 people in the world each year worldwide. Rapid and accurate diagnosis of rabies is important for instituting rapid containment measures and for advising the exposed people for postexposure treatment. The application of a rapid diagnostic tests in the field can greatly enhance disease surveillance and diagnostic activities, especially in resource poor settings. In this study, a total of 179 brain tissue samples collected from different rabies suspect animal species (113 dogs, 50 cattle, 10 cats, 3 goats, 2 horses, and 1 bear) were selected and tested using both rapid immunochromatographic kit and the reference standard fluorescent antibody test (FAT). We evaluated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of a rapid antigen detection test kit produced by BioNote, Inc. (Hwaseong-si, Korea) relative to a FAT for its fit-for-purpose for confirmation of clinical cases of rabies for early response and enhancing rabies surveillance. Results: Among 179 samples examined in this study, there was a concordance in results by the rapid test and FAT in 115 positive samples and 54 negative samples. Test results were discordant in 10 samples which were positive by FAT, but negative (false negative) by rapid kit. The rapid test kit showed a sensitivity of 92% (95% CI: 85.9 – 95.6) and specificity of 100% (95% CI: 93.4 – 100) using FAT as the reference standard. The positive and negative predictive values were found to be 100% (95% CI:96.7 – 100) and 84.4% (95% CI: 73.6 – 91.3), respectively. Overall, there was 94.4% (95% CI: 90 – 96.9) test agreement between rapid test and FAT (Kappa value = 0.874) with a positive percent agreement and negative percent agreement of 92 and 100%, respectively. Conclusions: Our finding demonstrated that the rapid test kit (BioNote) can be used for rabies surveillance and confirming clinical case of rabies in animals for making rapid decisions particularly controlling rabies outbreaks in resource poor settings.

Transhepatic forceps biopsy after PTCD for histological assessment of bile duct stenoses or occlusions

2019 ◽  
Vol 57 (02) ◽  
pp. 133-138
Author(s):  
Eva-Marie Warnken ◽  
Michael Uder ◽  
Hubert Stein ◽  
Michael Wucherer ◽  
Michael Lell ◽  
...  
Keyword(s):  
Predictive Value ◽  
False Negative ◽  
Short Term ◽  
Microsoft Excel ◽  
Ct Guided ◽  
Forceps Biopsy ◽  
Negative Results ◽  
False Negative Results ◽  
Pet Ct ◽  
Ct Guided Biopsy

Abstract Purpose The goal of this study was to evaluate the experience of 11 years of wire-guided forceps biopsy via PTCD in patients with obstructive jaundice. Materials and methods In a retrospective approach, 56 biopsies in 51 patients were analyzed (22 female, 29 male). Data was collected from 2006 to 2016. Mean age was 71 years (range: 34 – 86 years). Data was extracted from dig. Patients’ records (KIS, PACS, RIS) to be analyzed in Microsoft Excel. Results All 56 procedures were technically successful. Stenosis in anastomoses were benign due to scarring in 7 patients and in 9 due to papillitis or others. In 4 patients, results in anastomosis were malignant. In 19 patients without anastomosis, CCC was the diagnosis, thereof 10 klatskin, 9 stenosis in other locations, followed by gastric, pancreatic, and colon carcinoma in 5, 3, and 2 patients. Three patients had a CUP (multimetering in case of more than 1 related category). Overall results were 35 mal. and 16 benign, 76.8 % of all proc. had a correct histopathologic result, and 23.2 % were false negative. Sensitivity was 65.8 %, which results in negative predictive value of 58.1 %. There was no false positive and so specificity was 100 %, as was the positive predictive value. False negative results (no malignancy but clinically and imaging suspect) were corrected by rerunning the procedure, by CT-guided biopsy or by 1 PET-CT. In 1 case the surg. sample brought the result. Minor complications occurred in 8 patients: shivering in 1 case, distinct but hemodynamically not relevant hemobilia in 5 cases, 2 portovenal bleedings. All bleedings were short-term and self-limiting. Conclusion Despite good feasibility, low peri- and post-interv. risk and high validity the forceps biopsy via PTCD is not widely used. For experienced interventionalists, it is an effective method for obtaining histology.

scholarly journals The progestogen challenge test in postmenopausal women: clinical and morphologic aspects

1996 ◽  
Vol 114 (3) ◽  
pp. 1166-1172
Author(s):  
Claudia de Carvalho Ramos Bortoletto ◽  
Edmund Chada Baracat ◽  
Wagner José Gonçalves ◽  
João Norberto Stávalle ◽  
Geraldo Rodrigues de Lima ◽  
...  
Keyword(s):  
Postmenopausal Women ◽  
Predictive Value ◽  
Fasting Blood Glucose ◽  
False Negative ◽  
Challenge Test ◽  
Endometrial Biopsy ◽  
Clinical Aspects ◽  
Age At Menarche ◽  
Histopathological Analysis ◽  
Negative Results

The clinical aspects and anatomopathological patterns of 150 postmenopausal women were studied using the progestogen challenge test. An endometrial biopsy was obtained and submitted to the progestogen test. A histopathological analysis of the uterine mucosa from women with a positive progestogen test revealed that the endometrium was active in 44 percent of cases and atrophic or inactive in 56 percent. In contrast, among women with a negative response, the endometrium was atrophic in 94 percent of cases and active in 6 percent. Analysis of clinical aspects did not show significant differences between groups in terms of age; age at menarche and at menopause; fasting blood glucose levels; or body mass. However, postmenopausal time was significantly shorter for women with a positive test, with a correlation between postmenopausal time of one to two years and test positivity. The progestogen challenge test for the detection of atrophic endometrium presented 78.57 percent sensitivity, 77.05 percent specificity, 44 percent positive predictive value, and 94 percent negative predictive value. Thus, when negative, the test is highly valuable, indicating the presence of atrophic endometrium in 94 percent of cases. False-negative results occurred in only 6 percent of the subjects, with no case of hyperplasia detected. However, when the response to the test was positive, the endometrium was atrophic in 56 percent of the cases. We suggest that, in order to avoid invasive procedures, the progestogen challenge test be combined with other methods such as transvaginal ultrasonography.

scholarly journals Performance of SARS-CoV-2 Serology tests: Are they good enough?

2020 ◽  
Author(s):  
Isabelle Piec ◽  
Emma English ◽  
M Annette Thomas ◽  
Samir Dervisevic ◽  
William D Fraser ◽  
...  
Keyword(s):  
Sensitivity And Specificity ◽  
Respiratory Infections ◽  
Point Of Care ◽  
False Negative ◽  
Rapid Test ◽  
Diagnostic Sensitivity ◽  
Medical Community ◽  
Antibody Detection ◽  
Serological Tests ◽  
Negative Results

AbstractBackgroundIn the emergency of the SARS-CoV-2 pandemic, great efforts were made to quickly provide serology testing to the medical community however, these methods have been introduced into clinical practice without the complete validation usually required by the regulatory organizations.MethodsSARS-CoV-2 patient samples (n=43) were analysed alongside pre-pandemic control specimen (n=50), confirmed respiratory infections (n=50), inflammatory polyarthritis (n=22) and positive for thyroid stimulating immunoglobulin (n=30). Imprecision, diagnostic sensitivity and specificity and concordance were evaluated on IgG serologic assays from EuroImmun, Epitope Diagnostics (EDI), Abbott Diagnostics and DiaSorin and a rapid IgG/IgM test from Healgen.ResultsEDI and EuroImmun imprecision was 0.02-14.0% CV. Abbott and DiaSorin imprecision (CV) ranged from 5.2% - 8.1% and 8.2% - 9.6% respectively. Diagnostic sensitivity of the assays were 100% (CI: 80-100%) for Abbott, EDI and EuroImmun and 95% (CI: 73-100%) for DiaSorin at ≥14 days post PCR. Only the Abbott assay had a diagnostic specificity of 100% (CI: 91-100%). EuroImmun cross-reacted in 3 non-SARS-CoV-2 respiratory infections and 2 controls. The DiaSorin displayed more false negative results and cross-reacted in six cases across all conditions tested. EDI had one cross-reactive sample. The Healgen rapid test showed excellent sensitivity and specificity. Overall, concordance of the assays ranged from 76.1% to 97.9%.ConclusionsSerological tests for SARS-CoV-2 showed good analytical performance. The head-to-head analysis of samples revealed differences in results that may be linked to the use of nucleocapsid or spike proteins. The point of care device tested demonstrated adequate performance for antibody detection.

scholarly journals Screening of Extended-Spectrum β-Lactamases (ESBL)-producing Klebsiella pneumoniae with ChromID ESBL Media

2018 ◽  
Vol 10 (3) ◽  
pp. 217-21
Author(s):  
Emy Noerwidayati ◽  
Andaru Dahesihdewi ◽  
Osman Sianipar
Keyword(s):  
Likelihood Ratio ◽  
Predictive Value ◽  
Clinical Laboratory ◽  
False Negative ◽  
Clinical Isolates ◽  
True Negative ◽  
Nasal Sinus ◽  
Negative Results ◽  
Extended Spectrum ◽  
Sensitivity Specificity

BACKGROUND: Klepsiella pneumoniae, one of clinical isolates, is frequently found causative agent of hospital acquired infection. Currently, K. pneumoniae is found as extended-Spectrum β-lactamases (ESBL) producer, allowing it to become multidrugresistant. A clinical laboratory with limited facility needs a valid, reliable, inexpensive and simple laboratory test to control its infection and antimicrobial-resistancy. The aim of this study is to evaluate the diagnostic performance of a ESBL media to detect ESBL-producing K. pneumoniae.METHODS: An independent and blind comparative study of ChromID ESBL media and Double Disc Synergy Test (DDST) was conducted for detecting the clinical isolate of ESBL-producing K. pneumoniae. Clinical isolates of K. pneumoniae collected from the Clinical Laboratory of Dr. Sardjito Hospital were isolated.RESULTS: There were 103 clinical isolates of K. pneumoniae, which were isolated from urine, pus, blood, stool, cerebrospinal fluid, sputum, drain liquid, nasal sinus liquid, gastric wash, bronchi liquid, injury liquid and nasal swab. The number of true positive, true negative, false positive and false negative results were 74, 18, 9 and 2, respectively. Meanwhile, the sensitivity, specificity, positive predictive value, negative predictive value, likelihood ratio for positive result and likelihood ratio for negative result of the new ESBL media were 97.4%, 66.7%, 89.2%, 90%, 2.9 and 0.03, respectively.CONCLUSION: Since the new ESBL media and DDST results were similar, so the new ESBL media could be used for screening patients with clinical presentation that indicating a high suspicious of ESBL-producing bacteria.KEYWORDS: K. pneumoniae, ChromID ESBL, DDST, ESBL, sensitivity

scholarly journals Combined CTP- IGF-1 Score: A New Score for Assessment of Disease Severity in HCV Related Liver Cirrhosis

2022 ◽  
Author(s):  
Elsayed Ghannam ◽  
Salah Rozaik ◽  
Ramy Hasan Agwa ◽  
Ahmed Marwan ◽  
Mervat El-Sayed Mashaly ◽  
...  
Keyword(s):  
Liver Cirrhosis ◽  
Negative Predictive Value ◽  
Predictive Value ◽  
False Negative ◽  
The Body ◽  
P Value ◽  
Study Group ◽  
Negative Results ◽  
False Negative Results ◽  
Ctp Score

Abstract Background: Liver is the largest endocrine organ in the body. It is a key organ in insulin mediated metabolism, growth hormone and insulin like growth factors (IGF) pathway. Liver cirrhosis is the end result of many chronic diseases including hepatitis C virus infection. Child-Turcotte-Pugh (CTP) score is the standard used in assessment of hepatic reserve but it has its drawbacks in the form of subjective variables, hepatic encephalopathy and ascites. The aim of this work is to assess IGF-1 in patients with liver cirrhosis, correlate it with CTP score and assess value of modified combined CTP-IGF-1 score. Patients and Methods: 170 patients with CLD (liver cirrhosis) and 72 healthy controls in the study groups were enrolled in the study. All patients were subjected to thorough history, clinical examination and laboratory assessment. IGF-1 was measured and all patients were evaluated using CTP and CTP-IGF-1 scores. Results: IGF1 showed highly significant low values in the study group in comparison to controls (42.15 ± 27.976 and 66.31 ± 33.084 ng/ml respectively, p <0.001). It showed also highly significant negative correlation to CTP score in the study group (p < 0.001) with progressive decrements with CTP score stage progression where IGF1 levels were 48.32 ± 28.611, 40.28 ± 25.869 and 18.80 ± 15.953 ng/ml (mean ± standard deviation) in relation to CTP score groups A, B and C respectively (p value < 0.001). The combined CTP-IGF-1 score in comparison to the classic CTP score showed improved area under curve (0.848 and 0.854), sensitivity (71.2% and 88%), negative predictive value (41.7% and 53.7%), false negative results (49 and 19) and accuracy (75.73% and 83.98%) but decreased specificity (97.22% and 61.1%), positive predictive value (99.2% and 91.5%) and higher false positive results (1 and 14) respectively. Conclusion: IGF-1 show progressive decrements with progression of liver cirrhosis and is negatively correlated with CTP score. Addition of IGF-1 to CTP score to formulate combined score improves the AUC, sensitivity, negative predictive value and the accuracy of CTP score and decreases the false negative results.

scholarly journals Three-dimensional Transvaginal Ultrasound vs Office Hysteroscopy for Assessment of Uterine Cavity in Assisted Reproductive Program

2016 ◽  
Vol 8 (4) ◽  
pp. 290-293
Author(s):  
Ushma Patel
Keyword(s):  
Predictive Value ◽  
Transvaginal Ultrasound ◽  
False Negative ◽  
Three Dimensional ◽  
Uterine Cavity ◽  
Safe Procedure ◽  
Office Hysteroscopy ◽  
Diagnostic Efficacy ◽  
Menstrual Cycles ◽  
Negative Results

ABSTRACT Introduction The success of an assisted reproductive program (ARP) depends on the embryo quality and the intrauterine environment. It has been reported up until now that abnormal uterine findings occur in nearly 34 to 62% of infertile women worldwide. Due to this reason, uterine cavity evaluation is commonly recommended to screen for fibroids, polyps, adhesions, and mullerian abnormalities. Uterine cavity evaluation is usually accomplished with three-dimensional (3D) transvaginal ultrasound (TVS), sonohysterography, hysterosalpingography, and office hysteroscopy (OH). Materials and methods Uterine cavity evaluation was carried out in 239 infertile females undergoing ARP with twodimensional (2D) followed by 3D vaginal ultrasonography on day 21 of their menstrual cycles. Later, OH was carried out on 5th or 6th day of menstrual cycles. Results Out of 239 women, 3D TVS was abnormal in 28 (11.71%) and OH was abnormal in 53 (22.17%). Three-dimensional TVS agreed with OH in 16 (30.18%) abnormal cases and 179 (93.71%) normal cases. False-positive results for 3D TVS were 12 (6.28%) and false-negative results were 37 (69.81%). In our study, sensitivity of 3D TVS was 30.1%, specificity was 93.7%, positive predictive value was 57.1%, and negative predictive value was 82.8%. Conclusion Office hysteroscopy is an easy and safe procedure and has a better diagnostic efficacy than 3D TVS for uterine cavity evaluation in women undergoing ARP. How to cite this article Mishra VV, Patel U, Gandhi K. Threedimensional Transvaginal Ultrasound vs Office Hysteroscopy for Assessment of Uterine Cavity in Assisted Reproductive Program. J South Asian Feder Obst Gynae 2016;8(4):290-293.

scholarly journals Evaluation of anti-SARS-CoV-2 antibody testing in asymptomatic or mild COVID-19 patients in outbreak on a cruise ship

2021 ◽  
Author(s):  
Norihito Kaku ◽  
Fumitaka Nishimura ◽  
Yui Shigeishi ◽  
Rina Tachiki ◽  
Hironori Sakai ◽  
...  
Keyword(s):  
Genetic Test ◽  
False Negative ◽  
Enzyme Linked Immunosorbent Assay ◽  
Cruise Ship ◽  
Igg Antibodies ◽  
Antibody Testing ◽  
Predictive Values ◽  
Blood Samples ◽  
Negative Results ◽  
Genetic Test Results

AbstractBackgroundA few studies on antibody testing have focused on asymptomatic or mild coronavirus disease 2019 (COVID-19) patients with low initial anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody responses. Anti-SARS-CoV-2 antibody-testing performance was evaluated using blood samples from asymptomatic or mild COVID-19 patients.MethodsBlood samples were collected from 143 COVID-19 patients during an outbreak on a cruise ship 3 weeks after diagnosis. Simultaneously, a second SARS-CoV-2 genetic test was performed. Samples stored before the COVID-19 pandemic were also used to evaluate the lateral flow immunochromatographic assay (LFA) and electrochemiluminescence immunoassay (ECLIA). Titers of anti-SARS-CoV-2 IgM and IgG antibodies against the nucleocapsid and spike proteins were measured using the enzyme-linked immunosorbent assay to compare false-negative- with positive-result samples.ResultsSensitivity, specificity, positive-predictive, and negative-predictive values of LFA-detected IgM antibodies were 0.231, 1.000, 1.000, and 0.613, respectively; those of LFA-detected IgG antibodies were 0.483, 0.989, 0.972, and 0.601, respectively; and those of ECLIA-detected total antibodies were 0.783, 1.000, 1.000, and 0.848, respectively. IgM-, IgG-, and total-antibody positivity rates in the patients with negative results from the second genetic testing were 22.9%, 47.6%, and 72.4%, respectively. All antibody titers, especially those of the IgG antibody against nucleocapsid protein, were significantly lower in blood samples with false-negative results than in those with positive results.ConclusionsThese findings suggest that anti-SARS-CoV-2 antibody testing has lower performance in asymptomatic or mild COVID-19 patients than required in the guidelines, and situations in which it is useful are limited.Key pointsAnti-SARS-CoV-2 antibody testing in asymptomatic or mild COVID-19 patients is lower than the required clinical sensitivity, although it may be useful in patients at 3–4 weeks after symptom onset but with negative SARS-CoV-2 genetic test results.

scholarly journals Validity of protein-creatinine and protein-osmolality ratios in the estimation of massive proteinuria in children with nephrotic syndrome

2007 ◽  
Vol 47 (4) ◽  
pp. 139
Author(s):  
M. Sukmawati ◽  
K. Suarta
Keyword(s):  
Nephrotic Syndrome ◽  
Predictive Value ◽  
Diagnostic Tests ◽  
Quantitative Methods ◽  
False Negative ◽  
Creatinine Ratio ◽  
Negative Results ◽  
False Negative Results ◽  
Sensitivity Specificity ◽  
Posttest Probability

Background Children with nephrotic syndrome have massiveproteinuria, a rate of excretion equal to or greater than 40 mg/hour/m 2 body surface. The ability to quantitate massive urinaryprotein excretion is very important for both diagnostic andprognostic purposes. Quantification of proteinuria using 24-hoururine collection (Esbach) is difficult to do especially in children;moreover, many false-positive and false-negative results arereported for any semi-quantitative methods such as dipstick andsulfosalicylic acid measurement.Objective To determine the accuracy of protein-creatinine ratio(PCR) and protein-osmolality ratio (POR) in quantification ofmassive proteinuria in children with nephrotic syndrome.Methods Diagnostic tests were conducted on children withnephrotic syndrome aged 2-12 years with Esbach as a referencestandard. Sensitivity, specificity, positive predictive value (PPV),negative predictive value, (NPV), pre and posttest probabilitywere compared between PCR and POR.Results Study patients consisted of 47 children, 38 (81%) withmassive proteinuria. PCR has sensitivity of 92%, specificity of78%, PPV of 95%, NPV of 70% and posttest probability of 95%.POR has sensitivity of 76%, specificity of 78%, PPV of 94%, NPVof 44% and posttest probability of 94%.Conclusion Both PCR and POR are accurate to determine massiveproteinuria in children with nephrotic syndrome.

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