Conjunctival polymerase chain reaction-tests of 2019 novel coronavirus in patients in Shenyang, China

AbstractPurposeThe 2019 novel coronavirus(COVID-19) mainly transmitted by person-to-person through inhalation of respiratory droplets. We report the laboratory results of conjunctival PCR-tests and some clinical features of these patients in shenyang China.DesignThis is a cross-sectional non-randomized studySubjectsThe study include 14 confirmly diagnosed cases, 16 suspected cases and some medical observed patients.MethodsAll patients with diagnosed and suspected COVID-19 were admitted to a designated hospital in Shenyang, China. We collected conjunctival samples of these patients to do the laboratory tests by real time RT-PCR. Medical observed patients were enrolled if they had clinical symptoms. Then we analysed the PCR results and clinical data from eletronic medical records in order to find some relationships.Main Outcome MeasuresClinical condition and PCR results. of conjunctival swabs compared with other specimensResultsOne of the identified case coverted from suspected case without typical clinical symptoms. Twenty-two medical observed cases were removed because none of them converted to identified cases. One of the suspected converted to identified case recently. The included cases in our study are imported cases with less underlying diseases and the severity of their infection was relatively moderate. All the conjunctival results of PCR-test were negative. Two cases had typical clinical symptoms but were finally confirmed by repeated pharynxswabtests.ConclusionConjunctiva may be a transmission way of COVID-19. And ocular conjunctival swabs in combination with PCR test could be a non-invasive, convenient and feasible diagnostic method for identifying the infection of COVID-19. Emphasis on the false-negative results is vital.

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Conjunctival polymerase chain reaction-tests of 2019 novel coronavirus in patients in Shenyang,China

10.21203/rs.3.rs-17648/v1 ◽

2020 ◽

Author(s):

Li Xu ◽

Xinyue Zhang ◽

Wei Song ◽

Baijun Sun ◽

Jinping Mu ◽

...

Keyword(s):

Clinical Features ◽

Clinical Symptoms ◽

False Negative ◽

Suspected Case ◽

Negative Results ◽

False Negative Results ◽

Laboratory Results ◽

Polymerase Chain ◽

Novel Coronavirus ◽

Negative Detection

Abstract Background We report the laboratory results of conjunctival PCR-tests and some clinical features of these patients infected with COVID-19 in shenyang China.Methods We collected conjunctival samples of the patients to do the laboratory tests by PCR.Medical observed patients were enrolled if they had clinical symptoms. Then we analysed the PCR results and clinical features in order to find some relationships.Results The study include 14 confirmly diagnosed cases ,16 suspected cases and some medical observed patients.1 of the identified case coverted from suspected case.22 medical observed cases were removed because none of them converted to identified cases.1 of the suspected converted to identified case recently.All the conjunctival results of PCR-test were negative.Discussion The reasons of the negative detection results of PCR in conjunctival swabs were discussed.Conclusion Conjunctiva may be a transmission way of COVID-19.And ocular conjunctival swabs could be a diagnostic method for identifying the infection of COVID-19.Emphasis on the false-negative results is vital.

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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.

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Detection of Streptococcus pneumoniae in Sputum Samples by Real- Time PCR.

Anti-Infective Agents ◽

10.2174/2211352518999200629165108 ◽

2020 ◽

Vol 18 ◽

Author(s):

Pegah Shakib ◽

Mohammad Reza Zolfaghari

Keyword(s):

Streptococcus Pneumoniae ◽

Real Time ◽

Real Time Pcr ◽

False Negative ◽

Cross Sectional Study ◽

Laboratory Culture ◽

Cross Sectional ◽

Negative Results ◽

False Negative Results ◽

Pcr Method

Background: Conventional laboratory culture-based methods for diagnosis of Streptococcus pneumoniae are time-consuming and yield false negative results. Molecular methods including real-time (RT)-PCR rapid methods and conventional PCR due to higher sensitivity and accuracy have been replaced instead traditional culture assay. The aim of the current study was to evaluate lytA gene for detection of Streptococcus pneumoniae in the cerebrospinal fluid of human patients with meningitis using real-time PCR assay. Material and Methods: In this cross-sectional study, a total of 30 clinical specimens were collected from patients in a period from September to December 2018. In order to evaluate the presence of lytA gene, conventional and real-time PCR methods were used without culture. Results: From 30 sputum samples five (16.66%) isolates were identified as S. pneumoniae by lytA PCR and sequencing. Discussion: In this research, an accurate and rapid real-time PCR method was used, which is based on lytA gene for diagnosis of bacteria so that it can be diagnosed. Based on the sequencing results, the sensitivity for detection of lytA gene was 100% (5/5).

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Superiority of MALDI-TOF Mass Spectrometry over Real-Time PCR for SARS-CoV-2 RNA Detection

Viruses ◽

10.3390/v13050730 ◽

2021 ◽

Vol 13 (5) ◽

pp. 730

Author(s):

Magda Rybicka ◽

Ewa Miłosz ◽

Krzysztof Piotr Bielawski

Keyword(s):

Mass Spectrometry ◽

Gold Standard ◽

Viral Genome ◽

False Negative ◽

Rt Pcr ◽

Rna Detection ◽

Maldi Tof ◽

Negative Results ◽

False Negative Results ◽

Pcr Test

At present, the RT-PCR test remains the gold standard for early diagnosis of SARS-CoV-2. Nevertheless, there is growing evidence demonstrating that this technique may generate false-negative results. Here, we aimed to compare the new mass spectrometry-based assay MassARRAY® SARS-CoV-2 Panel with the RT-PCR diagnostic test approved for clinical use. The study group consisted of 168 suspected patients with symptoms of a respiratory infection. After simultaneous analysis by RT-PCR and mass spectrometry methods, we obtained discordant results for 17 samples (10.12%). Within fifteen samples officially reported as presumptive positive, 13 were positive according to the MS-based assay. Moreover, four samples reported by the officially approved RT-PCR as negative were positive in at least one MS assay. We have successfully demonstrated superior sensitivity of the MS-based assay in SARS-CoV-2 detection, showing that MALDI-TOF MS seems to be ideal for the detection as well as discrimination of mutations within the viral genome.

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Clinical Characteristics of Patients With Re-admitted of Novel Coronavirus 2019 (nCOVID-19) in Wenzhou, China

Frontiers in Public Health ◽

10.3389/fpubh.2021.649178 ◽

2021 ◽

Vol 9 ◽

Author(s):

Xinchun Ye ◽

Yuping Yuan ◽

Risheng Huang ◽

Aiqiong Cheng ◽

Zhijie Yu ◽

...

Keyword(s):

Clinical Symptoms ◽

Treatment Strategies ◽

Ct Imaging ◽

Negative Results ◽

Medical Observation ◽

Primary Focus ◽

Novel Coronavirus ◽

Clinical Records ◽

Test Result ◽

Pcr Test

Background: During the COVID-19 pandemic, many patients admitted to hospital for treatment have recovered and been discharged; however, in some instances, these same patients are re-admitted due to a second fever or a positive COVID-19 PCR test result. To ascertain whether it is necessary to treat these patients in hospitals, especially in asymptomatic cases, we summarize and analyze the clinical and treatment characteristics of patients re-admitted to hospital with a second COVID-19 infection.Methods: Of the 141 COVID-19 cases admitted to the Wenzhou Central Hospital between January 17, 2020, to March 5, 2020, which were followed until March 30, 2020, 12 patients were re-admitted with a second COVID-19 infection. Data was collected and analyzed from their clinical records, lab indexes, commuted tomography (CT), and treatment strategies.Results: Most of the 141 patients had positive outcomes from treatment, with only 12 (8.5%) being re-admitted. In this sub-group: one (8.3%) had a fever, a high white blood cell count (WBC), and progressive CT changes; and one (8.3%) had increased transaminase. The PCR tests of these two patients returned negative results. Another 10 patients were admitted due to a positive PCR test result, seven of which were clinically asymptomatic. Compared to the CT imaging following their initial discharge, the CT imaging of all patients was significantly improved, and none required additional oxygen or mechanical ventilation during their second course of treatment.Conclusions: The prognoses of the re-admitted patients were good with no serious cases. We conclude that home treatment with concentrated medical observation is a safe and feasible course of treatment if the patient returns a positive PCR test result but does not display serious clinical symptoms. During medical observation, patients with underlying conditions should remain a primary focus, but most do not need to be re-admitted to the hospital.

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Reducing False Negative PCR Test for COVID-19

International Journal of MCH and AIDS (IJMA) ◽

10.21106/ijma.421 ◽

2020 ◽

Vol 9 (3) ◽

pp. 408-410

Author(s):

Fatemeh Bahreini ◽

Rezvan Najafi ◽

Razieh Amini ◽

Salman Khazaei ◽

Saeid Bashirian

Keyword(s):

Polymerase Chain Reaction ◽

Real Time ◽

False Negative ◽

Rt Pcr ◽

Chain Reaction ◽

Creative Commons ◽

Negative Results ◽

False Negative Results ◽

Polymerase Chain ◽

Pcr Test

As the SARS-CoV-2 (COVID-19) pandemic spreads rapidly, there is need for a diagnostic test with high accuracy to detect infected individuals especially those without symptoms. Real-time polymerase chain reaction (RT-PCR) is a common molecular test for diagnosing SARS-CoV-2. If some factors are not taken into consideration when performing this test, it can have a relatively large number of false negative results. In this article, we discuss important considerations that could lead to false negative test reduction. Key words: • SARS-CoV-2 • COVID-19 • Real time polymerase chain reaction • RT-PCR test • Diagnosis • False negatives • Genetics • Emerging disease Copyright © 2020 Bahreini et al. Published by Global Health and Education Projects, Inc. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0)which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in this journal, is properly cited.

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Sensitivity of PAS histopathology stain for the diagnosis of onychomycosis at multicenter teaching hospitals, Pakistan.

The Professional Medical Journal ◽

10.29309/tpmj/2019.26.08.257 ◽

2019 ◽

Vol 26 (08) ◽

pp. 1213-1217

Author(s):

Muhammad Wajid Khurshid Sipra ◽

Zahid Mehmood Akhtar ◽

Tayyaba Batool

Keyword(s):

Periodic Acid ◽

False Negative ◽

Nail Plate ◽

Teaching Hospitals ◽

Periodic Acid Schiff ◽

Cross Sectional ◽

Medical College ◽

Negative Results ◽

False Negative Results ◽

Disease Study

The aim of this study was to determine the sensitivity of Periodic acid –Schiff (PAS) staining an early and quick effective diagnostic test of nail clipping with routine tests in the diagnosis of Onychomycosis. Background: The routine gold standard for diagnosis of fungal nail infections has been direct microscopy (KOH mount) and mycological culture which often yield delayed or weak/false negative results. However recent studies have suggested that nail plate biopsy using PAS stain is rapid method of detection that grasped the diagnosis and manage the disease. Study Design: Cross sectional descriptive study. Setting: 320 clinical diagnosed cases of onychomycosis performed at Department of Microbiology, Quaid-e-Azam Medical College Bahawalpur and Department of Histopathology King Edward medical University Lahore. Period: January 2012 to August 2018. Materials and Methods: The parameter looked in the sent investigation were histopathology PAS stain, mycological culture and microscopy. Presences of intensely stained reddish dots or threads like structures in between the cells of nail plate were considered to be positive results on histopathology with periodic acid Schiff (PAS). The microscopic study showed hyphae or spores and growth of organism concluded by morphological colony characteristics on Sabouraud's dextrose agar (SDA) periodically after 4 weeks. Result: out of total 320 cases, 81.25% was positive for histopathology PAS stain. Culture positivity was 60% and KOH mount recovered 52.5% positive. The combination of PAS stain and culture results showed 90.62% while Culture and KOH were 62.5% in nail clipping specimen. Conclusion: Histopathological PAS technique was found to be more effective than other laboratory methods for the diagnosis of Onychomycosis.

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Enhancement of the AMPLICOR Enterovirus PCR Test with a Coprecipitant

Journal of Clinical Microbiology ◽

10.1128/jcm.36.11.3408-3409.1998 ◽

1998 ◽

Vol 36 (11) ◽

pp. 3408-3409 ◽

Cited By ~ 8

Author(s):

E. William Taggart ◽

Carrie L. Byington ◽

David R. Hillyard ◽

John E. Robison ◽

Karen C. Carroll

Keyword(s):

Test Specimen ◽

False Negative ◽

Blind Study ◽

Specimen Preparation ◽

Background Signal ◽

Repeat Testing ◽

Negative Results ◽

Data Support ◽

False Negative Results ◽

Pcr Test

The incorporation of a commercially available coprecipitant into the AMPLICOR enterovirus PCR test specimen preparation enhanced the sensitivity and reproducibility of this assay. Fifty-five previously tested archived cerebrospinal fluids (CSF) specimens were tested in a blind study in duplicate with and without Pellet Paint coprecipitant (Novagen, Inc., Madison, Wis.). Of these specimens, 26 had previously been determined to be positive and 29 had previously been determined to be negative. All previously positive CSF specimens were positive when Pellet Paint was used and only 18 were positive without Pellet Paint. No previously negative specimens were positive on repeat testing with or without Pellet Paint. The background signal was not affected by the addition of Pellet Paint. These data support the utility of a coprecipitant in minimizing false-negative results.

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Laboratory markers included in the Corona Score can identify false negative results on COVID-19 RT-PCR in the emergency room

Biochemia Medica ◽

10.11613/bm.2020.030402 ◽

2020 ◽

Vol 30 (3) ◽

pp. 357-359

Author(s):

Roberto Assandri ◽

Ciro Canetta ◽

Giovanni Viganò ◽

Elisabetta Buscarini ◽

Alessandro Scartabellati ◽

...

Keyword(s):

Emergency Room ◽

False Negative ◽

Clinical Syndrome ◽

The Novel ◽

Emergency Rooms ◽

Negative Results ◽

Emergency Room Patients ◽

False Negative Results ◽

Wide Range ◽

Novel Coronavirus

After December 2019 outbreak in China, the novel Coronavirus infection (COVID-19) has very quickly overflowed worldwide. Infection causes a clinical syndrome encompassing a wide range of clinical features, from asymptomatic or oligosymptomatic course to acute respiratory distress and death. In a very recent work we preliminarily observed that several laboratory tests have been shown as characteristically altered in COVID-19. We aimed to use the Corona score, a validated point-based algorithm to predict the likelihood of COVID-19 infection in patients presenting at the Emergency rooms. This approach combines chest images-relative score and several laboratory parameters to classify emergency room patients. Corona score accuracy was satisfactory, increasing the detection of positive patients’ rate.

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Analysis and Prediction of COVID-19 Patients’ False Negative Results for SARS-CoV-2 Detection with Pharyngeal Swab Specimen: A Retrospective Study

10.1101/2020.03.26.20043042 ◽

2020 ◽

Cited By ~ 4

Author(s):

Hui Xu ◽

Li Yan ◽

Chun (Martin) Qiu ◽

Bo Jiao ◽

Yanyan Chen ◽

...

Keyword(s):

Nucleic Acid ◽

Time Window ◽

Clinical Symptoms ◽

False Negative ◽

Ct Imaging ◽

Nucleic Acid Detection ◽

False Negatives ◽

Negative Results ◽

False Negative Results ◽

Blood Routine

ABSTRACTBackgroundFalse negative results of SARS-CoV-2 nucleic acid detection pose threats to COVID-19 patients and medical workers alike.ObjectiveTo develop multivariate models to determine clinical characteristics that contribute to false negative results of SARS-CoV-2 nucleic acid detection, and use them to predict false negative results as well as time windows for testing positive.DesignRetrospective Cohort Study (Ethics number of Tongji Hospital: No. IRBID: TJ-20200320)SettingA database of outpatients in Tongji Hospital (University Hospital) from 15 January 2020 to 19 February 2020.Patients1,324 outpatients with COVID-19MeasurementsClinical information on CT imaging reports, blood routine tests, and clinic symptoms were collected. A multivariate logistic regression was used to explain and predict false negative testing results of SARS-CoV-2 detection. A multivariate accelerated failure model was used to analyze and predict delayed time windows for testing positive.ResultsOf the 1,324 outpatients who diagnosed of COVID-19, 633 patients tested positive in their first SARS-CoV-2 nucleic acid test (47.8%), with a mean age of 51 years (SD=14.9); the rest, which had a mean age of 47 years (SD=15.4), tested negative in the first test. “Ground glass opacity” in a CT imaging report was associated with a lower chance of false negatives (aOR, 0.56), and reduced the length of time window for testing positive by 26%. “Consolidation” was associated with a higher chance of false negatives (aOR, 1.57), and extended the length of time window for testing positive by 44%. In blood routine tests, basophils (aOR, 1.28) and eosinophils (aOR, 1.29) were associated with a higher chance of false negatives, and were found to extend the time window for testing positive by 23% and 41%, respectively. Age and gender also affected the significantly.LimitationData were generated in a large single-center study.ConclusionTesting outcome and positive window of SARS-CoV-2 detection for COVID-19 patients were associated with CT imaging results, blood routine tests, and clinical symptoms. Taking into account relevant information in CT imaging reports, blood routine tests, and clinical symptoms helped reduce a false negative testing outcome. The predictive AFT model, what we believe to be one of the first statistical models for predicting time window of SARS-CoV-2 detection, could help clinicians improve the accuracy and efficiency of the diagnosis, and hence, optimizes the timing of nucleic acid detection and alleviates the shortage of nucleic acid detection kits around the world.Primary Funding SourceNone.

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