Real world assessment of SARS-CoV-2 nasopharyngeal swab testing in a high burden COVID-19 region

Abstract Concerns persist regarding possible false negative results that may compromise COVID-19 containment. While obtaining a true false negative rate is infeasible, using real world observation these data suggest a possible false negative rate to be approximately 2.3%. Use of a sensitive, amplified RNA platform should reassure healthcare systems.

Download Full-text

Can We State Stable Bladder? How Many Repetitions Should We Do for an Appropriate Demonstration of Involuntary Detrusor Contraction?

Urologia Internationalis ◽

10.1159/000370163 ◽

2015 ◽

Vol 95 (1) ◽

pp. 86-91 ◽

Cited By ~ 2

Author(s):

Paulo Rodrigues ◽

Flávio Hering ◽

Eli Cieli ◽

Marcio DʼImperio ◽

João Carlos Campagnari

Keyword(s):

Wave Amplitude ◽

False Negative ◽

False Negative Rate ◽

Consistent Pattern ◽

Detrusor Contraction ◽

Negative Results ◽

Negative Rate ◽

False Negative Results ◽

Water Test ◽

Ice Water

Aims: Involuntary Detrusor Contraction (IDC) may alter therapeutic plans; therefore, urodynamic demonstration (UD) is pivotal. We explore if same session repetitions enhance its demonstration and minimize false-negative results. Methods: Two hundred fifty two women (mean age 47 ± 5.7) had 4 full repetitions of UD with the last round filled with 4°C fluid (Ice-water test). IDC was diagnosed if with at least 3 cm H2O after artifacts were ruled out. Results: 44.4% of the cases showed IDC in the first round of the exam but it could be demonstrated in 88.5% of the women if 4 rounds are taken into account. Only 2 cases showed IDC exclusively in the first round. Nine cases (3.5%) showed IDC in the first round and only on Ice-test, while all other IDC-detected cases revealed it in scattered patterns along the repetitions. Likewise, IDC detection on the second, third and fourth rounds varied widely and unpredictably, many failing to show a consistent pattern of presentation after its detection. IDC wave amplitude did not show any correlation to the detection. Conclusions: Urodynamic repetition is a necessary procedure where IDC is important to demonstrate, as its false-negative rate is high and its unpredictable pattern of detection may be improved by repetition.

Download Full-text

Scoring System for the Diagnosis of COVID-19

The Open Public Health Journal ◽

10.2174/1874944502013010413 ◽

2020 ◽

Vol 13 (1) ◽

pp. 413-414 ◽

Cited By ~ 1

Author(s):

Mohamed Farouk Allam

Keyword(s):

Scoring System ◽

Clinical Symptoms ◽

False Negative ◽

Nasopharyngeal Swab ◽

Rt Pcr ◽

Pcr Assay ◽

Negative Results ◽

False Negative Results ◽

Symptoms And Signs

Due to the international spread of COVID-19, the difficulty of collecting nasopharyngeal swab specimen from all suspected patients, the costs of RT-PCR and CT, and the false negative results of RT-PCR assay in 41% of COVID-19 patients, a scoring system is needed to classify the suspected patients in order to determine the need for follow-up, home isolation, quarantine or the conduction of further investigations. A scoring system is proposed as a diagnostic tool for suspected patients. It includes Epidemiological Evidence of Exposure, Clinical Symptoms and Signs, and Investigations (if available). This scoring system is simple, could be calculated in a few minutes, and incorporates the main possible data/findings of any patient.

Download Full-text

Evaluation of risk factors for false-negative results with an antigen-specific peripheral blood-based quantitative T cell assay (T-SPOT®.TB) in the diagnosis of active tuberculosis: A large-scale retrospective study in China

Journal of International Medical Research ◽

10.1177/0300060518757381 ◽

2018 ◽

Vol 46 (5) ◽

pp. 1815-1825 ◽

Cited By ~ 7

Author(s):

Chi Yang ◽

Shaojun Zhang ◽

Lan Yao ◽

Lin Fan

Keyword(s):

Risk Factors ◽

Retrospective Study ◽

Respiratory Diseases ◽

False Negative ◽

False Negative Rate ◽

Active Tuberculosis ◽

Pulmonary Tb ◽

Negative Results ◽

False Negative Results ◽

Negative Sputum

Objective To investigate the diagnostic efficacy of an interferon-γ release assay, T-SPOT®. TB, for diagnosing active tuberculosis (TB) and to identify risk factors for false-negative results. Methods This retrospective study enrolled consecutive patients with active TB and with non-TB respiratory diseases to evaluate the risk factors for false-negative results when using the T-SPOT®. TB assay for the diagnosis of active TB. Patients with active TB were categorized as having confirmed pulmonary TB, clinically diagnosed pulmonary TB or extrapulmonary TB (EPTB). Results This study analysed 4964 consecutive patients; 2425 with active TB and 2539 with non-TB respiratory diseases. Multivariate logistic regression analyses identified the following five factors that were all associated with an increased false-negative rate with the T-SPOT®. TB assay: increased age (odds ratio [OR] 1.018; 95% confidence interval [CI] 1.013, 1.024); decreased CD8+ count (OR 0.307; 95% CI 0.117, 0.803); negative sputum acid-fast bacilli (AFB) smear staining (OR 1.821; 95% CI 1.338, 2.477); negative mycobacterial cultures (OR 1.379; 95% CI 1.043, 1.824); and absence of EPTB (OR 1.291; 95% CI 1.026, 1.623). Conclusions Increased age, decreased CD8+ count, negative sputum AFB smear results, negative sputum mycobacterial cultures and absence of EPTB might lead to an increased false-negative rate when using the T-SPOT®. TB assay.

Download Full-text

One-Year Update on Salivary Diagnostic of COVID-19

Frontiers in Public Health ◽

10.3389/fpubh.2021.589564 ◽

2021 ◽

Vol 9 ◽

Author(s):

Douglas Carvalho Caixeta ◽

Stephanie Wutke Oliveira ◽

Leia Cardoso-Sousa ◽

Thulio Marquez Cunha ◽

Luiz Ricardo Goulart ◽

...

Keyword(s):

Healthcare Professionals ◽

Close Contact ◽

False Negative ◽

Nasopharyngeal Swab ◽

Frontline Workers ◽

Non Invasive ◽

Negative Results ◽

False Negative Results ◽

One Year ◽

Frontline Healthcare Workers

Background: Coronavirus disease 2019 (COVID-19) is a global health problem, which is challenging healthcare worldwide. In this critical review, we discussed the advantages and limitations in the implementation of salivary diagnostic platforms of COVID-19. The diagnostic test of COVID-19 by invasive nasopharyngeal collection is uncomfortable for patients and requires specialized training of healthcare professionals in order to obtain an appropriate collection of samples. Additionally, these professionals are in close contact with infected patients or suspected cases of COVID-19, leading to an increased contamination risk for frontline healthcare workers. Although there is a colossal demand for novel diagnostic platforms with non-invasive and self-collection samples of COVID-19, the implementation of the salivary platforms has not been implemented for extensive scale testing. Up to date, several cross-section and clinical trial studies published in the last 12 months support the potential of detecting SARS-CoV-2 RNA in saliva as a biomarker for COVID-19, providing a self-collection, non-invasive, safe, and comfortable procedure. Therefore, the salivary diagnosis is suitable to protect healthcare professionals and other frontline workers and may encourage patients to get tested due to its advantages over the current invasive methods. The detection of SARS-CoV-2 in saliva was substantial also in patients with a negative nasopharyngeal swab, indicating the presence of false negative results. Furthermore, we expect that salivary diagnostic devices for COVID-19 will continue to be used with austerity without excluding traditional gold standard specimens to detect SARS-CoV-2.

Download Full-text

False-Negative Nasopharyngeal Swab RT-PCR Assays in Typical COVID-19: Role of Ultra-low-dose Chest CT and Bronchoscopy in Diagnosis

European Journal of Case Reports in Internal Medicine ◽

10.12890/2020_001680 ◽

2020 ◽

Author(s):

Marco Marando ◽

Adriana Tamburello ◽

Pietro Gianella

Keyword(s):

Low Dose ◽

False Negative ◽

Nasopharyngeal Swab ◽

Rt Pcr ◽

Oral Swab ◽

Negative Results ◽

False Negative Results ◽

Polymerase Chain ◽

Pcr Assays

On 11 March 2020, the WHO declared COVID-19 a pandemic and global health emergency. We describe the clinical features and role of ultra-low-dose chest computed tomography (CT) and bronchoscopy in the diagnosis of coronavirus disease (COVID-19). In our patient, who was highly suggestive clinically and radiologically for COVID-19, we had two false-negative results for nasopharyngeal and oral swab reverse-transcriptase polymerase chain reaction (RT-PCR) assays for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Eventually, we confirmed the diagnosis using bronchoscopy and bronchoalveolar lavage (BAL).

Download Full-text

Evaluation of the true false negative rate in cytology

American Journal of Obstetrics and Gynecology ◽

10.1016/0002-9378(64)90172-3 ◽

1964 ◽

Vol 89 (6) ◽

pp. 723-726 ◽

Cited By ~ 30

Author(s):

Ralph M. Richart

Keyword(s):

False Negative ◽

False Negative Rate ◽

Negative Rate ◽

True False

Download Full-text

SARS-CoV-2 Nasopharyngeal Swab Testing—False-Negative Results From a Pervasive Anatomical Misconception

JAMA Otolaryngology–Head & Neck Surgery ◽

10.1001/jamaoto.2020.2946 ◽

2020 ◽

Vol 146 (11) ◽

pp. 993 ◽

Cited By ~ 4

Author(s):

Thomas S. Higgins ◽

Arthur W. Wu ◽

Jonathan Y. Ting

Keyword(s):

False Negative ◽

Nasopharyngeal Swab ◽

Negative Results ◽

False Negative Results

Download Full-text

Effect of omeprazole, rabeprazole, and rebamipide on the accuracy of urea breath test in patients with Helicobacter pylori infection

Asian Biomedicine ◽

10.2478/abm-2010-0042 ◽

2010 ◽

Vol 4 (2) ◽

pp. 337-342

Author(s):

Duangporn Thong-Ngam ◽

Maneerat Chayanupatkul ◽

Thirada Thongbai

Keyword(s):

Proton Pump Inhibitors ◽

Proton Pump ◽

Breath Test ◽

False Negative ◽

False Negative Rate ◽

Urea Breath Test ◽

Once Daily ◽

Negative Results ◽

Negative Rate ◽

H Pylori

Abstract Background: The urea breath test (UBT) has been widely used for H. pylori eradication after treatment. The breath test could be adversely affected by various factors including proton pump inhibitors (PPIs) that are also used in the therapy for H. pylori infection. Objective: Determine the effect of omeprazole, rabeprazole and the mucoprotective agent rebamipide, on the UBT. Methods: Fifty-six patients with dyspepsia and positive for H. pylori by rapid urease test were enrolled. They were classified into three groups: Group 1 (n=25) received omeprazole 20 mg once daily, group 2 (n=13) received rabeprazole 20 mg once daily, and group 3 (n=18) received rebamipide 100 mg three times a day. All patients received a 14-day course of their medications. UBT was performed on day 0 as a baseline and on day 14 in all patients. In patient with negative results of UBT on day 14, the UBT was performed in consecutive week until the test became positive. Results: Fifty-six patients (20 men and 36 women) participated in the study. Their mean age was 46.77±14.3 years. False negative rate after 14-day treatment in omeprazole, rabeprazole and rebamipide group were 20.0%, 30.8%, and 0% respectively. There was a significant difference between 13C level in patients with negative and positive UBT results (2.7±0.7 vs.22.9±3.7/mL, p=0.025). The reversal of false negative to true positive tests occurred within two weeks after discontinuation of omeprazole and rabeprazole. Conclusion: Proton pump inhibitors had an effect on the accuracy of H. pylori detection using UBT. Rabeprazole revealed a higher false negative rate in the UBT than omeprazole. The mucoprotective drug, rebamipide, did not influence negative results in the UBT.

Download Full-text