False-negative HIV antibody test results

Abstract Background Between December 2018 and January of 2019, we evaluated the accuracy of the point-of-care Hepatitis C (HCV) antibody test (POC; OraQuick HCV) used at a community-based needle and syringe exchange program serving persons who inject drugs in Tallinn, Estonia. Methods We compared the results of screening for HCV antibodies by OraQuick (oral swab) and enzyme immunoassay (EIA; blood draw) and assessed test results implications in a high prevalence setting. Findings Of the 100 participants, 88 (88%) had reactive POC test results, and 93 were HCV antibody positive on EIA testing. Sensitivity, specificity and negative predictive value (NPV) for the POC assay with EIA as the relevant reference test were as follows: 94.6% (95% CI 90.0–99.2%), 100% and 58.3% (95% CI 30.4–86.2%). Of the 12 testing, HCV-negative with the POC only 7 (58.3%) were true negatives. Conclusions Oral swab rapid testing HCV screening in this nonclinical setting was sensitive and specific but had unacceptably low NPV. In high prevalence settings, POC tests with high sensitivity and that directly measure HCV RNA may be warranted.

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A Nationwide Survey of COVID-19 Testing in LGBTQ+ Populations in the United States

Public Health Reports ◽

10.1177/00333549211018190 ◽

2021 ◽

pp. 003335492110181

Author(s):

Richard J. Martino ◽

Kristen D. Krause ◽

Marybec Griffin ◽

Caleb LoSchiavo ◽

Camilla Comer-Carruthers ◽

...

Keyword(s):

United States ◽

Gay Men ◽

Antibody Test ◽

Nationwide Survey ◽

The United States ◽

Sociodemographic Characteristics ◽

Full Time ◽

Test Results ◽

Antibody Testing ◽

And Gender

Objectives Lesbian, gay, bisexual, transgender, or queer and questioning (LGBTQ+) people and populations face myriad health disparities that are likely to be evident during the COVID-19 pandemic. The objectives of our study were to describe patterns of COVID-19 testing among LGBTQ+ people and to differentiate rates of COVID-19 testing and test results by sociodemographic characteristics. Methods Participants residing in the United States and US territories (N = 1090) aged ≥18 completed an internet-based survey from May through July 2020 that assessed COVID-19 testing and test results and sociodemographic characteristics, including sexual orientation and gender identity (SOGI). We analyzed data on receipt and results of polymerase chain reaction (PCR) and antibody testing for SARS-CoV-2 and symptoms of COVID-19 in relation to sociodemographic characteristics. Results Of the 1090 participants, 182 (16.7%) received a PCR test; of these, 16 (8.8%) had a positive test result. Of the 124 (11.4%) who received an antibody test, 45 (36.3%) had antibodies. Rates of PCR testing were higher among participants who were non–US-born (25.4%) versus US-born (16.3%) and employed full-time or part-time (18.5%) versus unemployed (10.8%). Antibody testing rates were higher among gay cisgender men (17.2%) versus other SOGI groups, non–US-born (25.4%) versus US-born participants, employed (12.6%) versus unemployed participants, and participants residing in the Northeast (20.0%) versus other regions. Among SOGI groups with sufficient cell sizes (n > 10), positive PCR results were highest among cisgender gay men (16.1%). Conclusions The differential patterns of testing and positivity, particularly among gay men in our sample, confirm the need to create COVID-19 public health messaging and programming that attend to the LGBTQ+ population.

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Evaluating Presence/Absence of Target Microbes in Microbiological Tests

Journal of AOAC International ◽

10.1093/jaoac/83.6.1429 ◽

2000 ◽

Vol 83 (6) ◽

pp. 1429-1434

Author(s):

Robert J Blodgett ◽

Anthony D Hitchins

Keyword(s):

Performance Studies ◽

Collaborative Study ◽

False Negative ◽

The Other ◽

Test Results ◽

Logistic Curve ◽

Microbiological Method ◽

Test Portion ◽

Method Performance ◽

Data Set

Abstract A typical qualitative microbiological method performance (collaborative) study gathers a data set of responses about a test for the presence or absence of a target microbe. We developed 2 models that estimate false-positive and false-negative rates. One model assumes a constant probability that the tests will indicate the target microbe is present for any positive concentration in the test portion. The other model assumes that this probability follows a logistic curve. Test results from several method performance studies illustrate these estimates.

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A simple rule for interpreting COVID-19 antibody test results, by seroprevalence and vaccination status

Journal of Microbiology Immunology and Infection ◽

10.1016/j.jmii.2021.02.008 ◽

2021 ◽

Author(s):

Yi-Hsuan Chen ◽

Chi-Tai Fang

Keyword(s):

Antibody Test ◽

Vaccination Status ◽

Simple Rule ◽

Test Results

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Three Years of Experience With Random Urinary Homovanillic and Vanillylmandelic Acid Levels in the Diagnosis of Neuroblastoma

PEDIATRICS ◽

10.1542/peds.79.2.203 ◽

1987 ◽

Vol 79 (2) ◽

pp. 203-205

Author(s):

Mendel Tuchman ◽

Margaret L. R. Ramnaraine ◽

William G. Woods ◽

William Krivit

Keyword(s):

False Positive ◽

Homovanillic Acid ◽

False Negative ◽

False Negative Rate ◽

Urine Samples ◽

Vanillylmandelic Acid ◽

Test Results ◽

Upper Limit ◽

Positive Results ◽

Rule Out

During the last 3 years, random urine samples from 408 patients were tested for elevated homovanillic acid (HVA) and vanillylmandelic acid (VMA) levels to rule out the diagnosis of neuroblastoma. Thirty-seven of these patients had elevated HVA and/or VMA levels, and neuroblastoma was subsequently diagnosed. In three additional patients with negative test results (normal HVA and VMA levels), tumors were subsequently diagnosed (false-negative rate of 7.5%). Ten percent of the patients with neuroblastoma had normal HVA and 27.5% had normal VMA levels at the time of diagnosis. Only one patient (2.5%) with neuroblastoma had elevated VMA levels in the presence of normal HVA levels. More than 60% of the patients with neuroblastoma had urinary HVA and/or VMA levels higher than twice the upper limit of normal. No false-positive results were encountered. Age and stage distributions of the patients are shown, and the significance of the results is discussed.

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AI-Empowered Computational Examination of Chest Imaging for COVID-19 Treatment: A Review

Frontiers in Artificial Intelligence ◽

10.3389/frai.2021.612914 ◽

2021 ◽

Vol 4 ◽

Author(s):

Hanqiu Deng ◽

Xingyu Li

Keyword(s):

False Negative ◽

Screening Tools ◽

Polymerase Chain Reaction Test ◽

Test Results ◽

First Case ◽

Lung Scan ◽

Screening Efficiency ◽

Polymerase Chain ◽

Chain Reaction Test ◽

Full Swing

Since the first case of coronavirus disease 2019 (COVID-19) was discovered in December 2019, COVID-19 swiftly spread over the world. By the end of March 2021, more than 136 million patients have been infected. Since the second and third waves of the COVID-19 outbreak are in full swing, investigating effective and timely solutions for patients’ check-ups and treatment is important. Although the SARS-CoV-2 virus-specific reverse transcription polymerase chain reaction test is recommended for the diagnosis of COVID-19, the test results are prone to be false negative in the early course of COVID-19 infection. To enhance the screening efficiency and accessibility, chest images captured via X-ray or computed tomography (CT) provide valuable information when evaluating patients with suspected COVID-19 infection. With advanced artificial intelligence (AI) techniques, AI-driven models training with lung scans emerge as quick diagnostic and screening tools for detecting COVID-19 infection in patients. In this article, we provide a comprehensive review of state-of-the-art AI-empowered methods for computational examination of COVID-19 patients with lung scans. In this regard, we searched for papers and preprints on bioRxiv, medRxiv, and arXiv published for the period from January 1, 2020, to March 31, 2021, using the keywords of COVID, lung scans, and AI. After the quality screening, 96 studies are included in this review. The reviewed studies were grouped into three categories based on their target application scenarios: automatic detection of coronavirus disease, infection segmentation, and severity assessment and prognosis prediction. The latest AI solutions to process and analyze chest images for COVID-19 treatment and their advantages and limitations are presented. In addition to reviewing the rapidly developing techniques, we also summarize publicly accessible lung scan image sets. The article ends with discussions of the challenges in current research and potential directions in designing effective computational solutions to fight against the COVID-19 pandemic in the future.

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JUVENILE LYMPHOCYTIC THYROIDITIS

PEDIATRICS ◽

10.1542/peds.30.6.917 ◽

1962 ◽

Vol 30 (6) ◽

pp. 917-926

Author(s):

Krishna M. Saxena ◽

John D. Crawford

Keyword(s):

Antibody Test ◽

Lymphocytic Infiltration ◽

Thyroid Stimulating Hormone ◽

Test Results ◽

Lymphocytic Thyroiditis ◽

Results Of Treatment ◽

Two Factors ◽

The Moment ◽

Tsh Stimulation ◽

Stimulation Of

Lymphocytic thyroiditis was the most common cause of nontoxic goiters in childhood, comprising about 40% of these and 20% of all goiters seen in our pediatric endocrine clinic. The diagnosis should be considered whenever a nontoxic goiter does not diminish significantly in size within about two weeks in response to thyroid-stimulating-hormone (TSH) suppressive doses of USP thyroid. Observations on 32 children with lymphocytic thyroiditis have been recorded. The diagnosis was proven histologically in 23. In nine patients the diagnosis was presumptive. The condition occurred mostly in preadolescent girls as a slowly developing firm, diffuse, and smooth or nubbly goiter with or without symptoms of anxiety, nervousness and pressure in the neck. The majority of patients were euthyroid when first encountered, though examples both of mild hyperthyroidism and hypothyroidism were also seen. A high protein-bound iodine value, a large discrepancy between protein-bound iodine and butanol-extractable iodine, and positive tanned erythrocyte antibody test results provided the best diagnostic criteria apart from biopsy. The pathological picture is one of hyperplasia with lymphocytic infiltration and atrophy of thyroid follicles and epithelium. Treatment consisted in giving TSH suppressive doses of thyroid for a prolonged period. The results of treatment were not entirely satisfactory. Genetic predisposition, probably manifested in an abnormal cellular hypersensitivity, and excessive TSH stimulation of the thyroid seem for the moment the two factors in pathogenesis best supported by laboratory evidence.

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

10.21203/rs.2.19414/v3 ◽

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.

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