Clinical implications of different specimen types for nucleic acid testing in two cases of COVID-19

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid test is currently the gold standard for diagnosing coronavirus disease 2019 (COVID-19). This disease requires high-quality viral nucleic acid tests, and selecting the type of specimen from patients, who are at different disease stages, to use in the nucleic acid test is challenging. This article reports in detail the diagnosis and treatment process for two patients with confirmed COVID-19 and analyzes the results of the SARS-CoV-2 nucleic acid tests that were used for different types of specimens (sputum from deep cough, nasopharyngeal swab, and feces). The nucleic acid testing results of sputum from deep cough showed the best performance for positive detection. Our findings provide a reference for selecting the most suitable specimen for the clinical diagnosis of COVID-19 and improving the positive detection rate.

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Role of novel deep-learning-based CT used in management and discharge of COVID-19 patients at a “square cabin” hospital in China

10.21203/rs.3.rs-28201/v1 ◽

2020 ◽

Author(s):

Qingcheng Meng ◽

Wentao Liu ◽

Xinmin Dou ◽

Jiaqi Zhang ◽

Anlan Sun ◽

...

Keyword(s):

Computed Tomography ◽

Deep Learning ◽

Nucleic Acid ◽

Volume Ratio ◽

Respiratory Pathogen ◽

Normal Lung ◽

The Novel ◽

Chest Computed Tomography ◽

Nucleic Acid Test ◽

Acid Test

Abstract Background: The chest computed tomography (CT) had been used to define the diagnostic and discharge criteria for COVID-19. However, it is difficult to determine the suitability for discharge of a patient with COVID-19 based on CT features in a clinical setting. Deep learning (DL) technology has demonstrated great success in the medical imaging.Purpose: This study applied the novel deep learning (DL) on chest computed tomography (CT) of COVID-19 patients with consecutive negative respiratory pathogen nucleic acid test results at a “square cabin” hospital in Wuhan, China, with the intent to standardize criteria for discharge.Methods: The study included 270 patients (102men, 168 women; mean age, 51.9 ± 15.6[18–65] years) who had two consecutive negative respiratory pathogen tests (sampling interval: ≥1 day) and underwent low-dose CT 1 day after the first negative test, with strict adherence to epidemic prevention standards. The chest CT of COVID-19 patients with negative nucleic acid tests were evalued by DL, and the standard for discharge was a total volume ratio of lesions to lung of less than 50% determined by DL.Results: The average intersection over union is 0.7894. Fifty-seven (21.1%) and 213 (78.9%) patients exhibited normal lung findings and pneumonia, respectively. 54.0% (115/213) involved mild interstitial fibrosis. 18.8% (40/213) had total volume ratio of lesions to lung of more than and equal to 50% according to our severity scale and were monitored continuously in hospital, and three cases of which had a positive follow-up nucleic acid test during hospital observation. None of the 230 discharged cases later tested positive or exhibited pneumonia progression. Conclusions: The novel DL enables the accurate management of COVID-19 patients and can help avoid cluster transmission or exacerbation due to patients with false negitive acid test.

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Diagnosis of Acute Respiratory Syndrome Coronavirus 2 Infection by Detection of Nucleocapsid Protein

10.1101/2020.03.07.20032524 ◽

2020 ◽

Cited By ~ 36

Author(s):

Bo Diao ◽

Kun Wen ◽

Jian Chen ◽

Yueping Liu ◽

Zilin Yuan ◽

...

Keyword(s):

Nucleic Acid ◽

Nucleocapsid Protein ◽

Viral Antigen ◽

Nasopharyngeal Swab ◽

Specific Marker ◽

Reference Standard ◽

Simple Method ◽

Nucleic Acid Test ◽

Protein Assay ◽

Acid Test

SummaryBACKGROUNDNucleic acid test and antibody assay have been employed in the diagnosis for SARS-CoV-2 infection, but the use of viral antigen for diagnosis has not been successfully developed. Theoretically, viral antigen is the specific marker of the virus and precedes antibody appearance within the infected population. There is a clear need of detection of viral antigen for rapid and early diagnosis.METHODSWe included a cohort of 239 participants with suspected SARS-CoV-2 infection from 7 centers for the study. We measured nucleocapsid protein in nasopharyngeal swab samples in parallel with the nucleic acid test. Nucleic acid test was taken as the reference standard, and statistical evaluation was taken in blind. We detected nucleocapsid protein in 20 urine samples in another center, employing nasopharyngeal swab nucleic acid test as reference standard.RESULTSWe developed a fluorescence immunochromatographic assay for detecting nucleocapsid protein of SARS-CoV-2 in nasopharyngeal swab sample and urine within 10 minutes. 100% of nucleocapsid protein positive and negative participants accord with nucleic acid test for same samples. Further, earliest participant after 3 days of fever can be identified by the method. In an additional preliminary study, we detected nucleocapsid protein in urine in 73.6% of diagnosed COVID-19 patients.CONCLUSIONSThose findings indicate that nucleocapsid protein assay is an accurate, rapid, early and simple method for diagnosis of COVID-19. Appearance of nucleocapsid protein in urine coincides our finding of the SARS-CoV-2 invading kidney and might be of diagnostic value.

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A Research on the Results of Viral Nucleic Acid Tests and CT Imaging Variation of Patients with COVID-19

10.1101/2020.05.08.20037556 ◽

2020 ◽

Author(s):

Meng Xu ◽

Xun Liu ◽

Chuhong Su ◽

Yuping Zeng ◽

Jinqian Zhang ◽

...

Keyword(s):

Nucleic Acid ◽

Recovery Period ◽

Ct Imaging ◽

Nucleic Acid Detection ◽

Test Results ◽

Viral Nucleic Acid ◽

Nucleic Acid Test ◽

Acid Test ◽

Pulmonary Ct ◽

Nucleic Acid Tests

AbstractBackgroundCoronavirus disease 2019 (COVID-19) has become a global health problem. We aim to investigate the changes in the results of viral nucleic acid tests on pharyngeal swabs and feces of patients with COVID-19 and CT imaging of lungs as the disease progresses.MethodsSeven patients with COVID-19 in the third affiliated hospital of Sun Yat-sen University Yuedong Hospital were retrospectively enrolled with clinical features, including imaging staging, and performance characteristics of viral nucleic acid test results of pharyngeal swabs and feces. The dynamic changes of these features were observed during hospitalization, and therapeutic effect and prognosis of patients were evaluated.ResultsThe results of seven cases with COVID-19 were positive for viral nucleic acid tests on pharyngeal swabs early after the onset of symptoms, and then turned negative; while the results of viral nucleic acid tests on feces were persistently positive in the mid-term clinical treatment and recovery period. And the viral nucleic acid test results were capricious in three cases. Pulmonary CT imaging showed characteristic changes in early, advanced and recovery phases.ConclusionThe application of viral nucleic acid detection and pulmonary CT imaging can be used for screening of suspected cases. Fecal nucleic acid test should be recommended as the reference of discharge standard, in order to minimize the risk of transmission from digestive tract.

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Laboratory Tests for the Diagnosis of Clostridium difficile

Clinics in Colon and Rectal Surgery ◽

10.1055/s-0039-3400476 ◽

2020 ◽

Vol 33 (02) ◽

pp. 073-081 ◽

Cited By ~ 3

Author(s):

Karen C. Carroll ◽

Masako Mizusawa

Keyword(s):

Nucleic Acid ◽

Poor Performance ◽

Laboratory Diagnosis ◽

The United States ◽

Test Methods ◽

Chemotherapeutic Agents ◽

Nucleic Acid Test ◽

Advantages And Disadvantages ◽

Acid Test ◽

Nucleic Acid Tests

Abstract Clostridium (reclassified as “Clostridioides”) difficile is an anaerobic, gram-positive bacterium that causes significant disease through elaboration of two potent toxins in patients whose normal gut microbiota has been altered through antimicrobial or chemotherapeutic agents (dysbiosis). The optimum method of laboratory diagnosis is still somewhat controversial. Recent practice guidelines published by professional societies recommend a two-step approach beginning with a test for glutamate dehydrogenase (GDH), followed by a toxin test and/or a nucleic acid test. Alternatively, in institutions where established clinical algorithms guide testing, a nucleic acid test alone is acceptable. Nucleic acid tests are the methods of choice in approximately 50% of laboratories in the United States. These tests are considered as the most sensitive methods for detection of C. difficile in stool and are the least specific. Because of the lower specificity with nucleic acid tests, some clinicians believe that toxin enzyme immunoassays are better predictors of disease, despite their known poor performance in certain patient populations. This review will discuss the advantages and disadvantages of the currently available test methods for the diagnosis of C. difficile with a brief mention of some novel assays that are currently in clinical trials.

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Metode Nucleic Acid Test untuk Uji Saring Virus Hepatitis B pada Darah Donor dengan Hepatitis B Occult

Jurnal Biotek Medisiana Indonesia ◽

10.22435/jbmi.v4i2.5123.51-58 ◽

2016 ◽

Vol 4 (2) ◽

Author(s):

Ulfah Suryani ◽

Vivi Setiawaty

Keyword(s):

Nucleic Acid ◽

Hepatitis B ◽

Virus Hepatitis ◽

Nucleic Acid Test ◽

Acid Test

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Cost-effectiveness of nucleic acid test screening of volunteer blood donations for hepatitis B, hepatitis C and human immunodeficiency virus in the United States

Vox Sanguinis ◽

10.1111/j.0042-9007.2004.00379.x ◽

2004 ◽

Vol 86 (1) ◽

pp. 28-40 ◽

Cited By ~ 99

Author(s):

D. A. Marshall ◽

S. H. Kleinman ◽

J. B. Wong ◽

J. P. AuBuchon ◽

D. T. Grima ◽

...

Keyword(s):

United States ◽

Human Immunodeficiency Virus ◽

Cost Effectiveness ◽

Hepatitis C ◽

Nucleic Acid ◽

Hepatitis B ◽

The United States ◽

Nucleic Acid Test ◽

Immunodeficiency Virus ◽

Acid Test

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What is the meaning of a nonresolved viral nucleic acid test-reactive minipool?

Transfusion ◽

10.1111/trf.12818 ◽

2014 ◽

Vol 55 (2) ◽

pp. 395-404 ◽

Cited By ~ 4

Author(s):

Lunan Wang ◽

Le Chang ◽

Yunzheng Xie ◽

Chengyin Huang ◽

Lei Xu ◽

...

Keyword(s):

Nucleic Acid ◽

Viral Nucleic Acid ◽

Nucleic Acid Test ◽

Acid Test

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Cases Report of Cured Novel Coronavirus-infected Pneumonia Patients with Viral Nucleic Acid Test Positive in Fecal Specimens

10.21203/rs.3.rs-20799/v1 ◽

2020 ◽

Author(s):

Mei Han ◽

Jingbo Zou ◽

Wenguang Tian ◽

Xiaoyu Wei ◽

Yang Zhou ◽

...

Keyword(s):

Nucleic Acid ◽

Molecular Diagnostic ◽

Clinical Practices ◽

Rt Pcr ◽

Viral Nucleic Acid ◽

Nucleic Acid Test ◽

Assessment Standard ◽

Novel Coronavirus ◽

Acid Test ◽

Respiratory Specimens

Abstract Background: The outbreak of the novel coronavirus in China (COVID-19) represents a significant and urgent threat to global health. We report here five cases of COVID-19 infection patients in our clinical practices who are medically stable and presumed to successfully “cleared” the virus after antiviral treatments. Case presentation: The clinical evaluation depends on the viral nucleic acid test in respiratory specimens by real-time PCR reverse transcription (RT-PCR) assays according to the authorized guidance. We found that the stool samples of these cured patients remain positive in RT-PCR assay while the virus is undetectable in respiratory specimens. RT-PCR molecular diagnostic assay was designed to specifically detect the presence of viral RNA. Thus, the positive result in the fecal specimens implies the existence of viable virions with the patients. Conclusions: This highlights the importance to look closely at the assessment standard of medical treatment, as well as the need for reevaluation of the criteria for the initial screening, prevention, and care of patients with this emerging infection.

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