Feasibility and safety of a symptom-based strategy to discontinue infection control precautions for patients hospitalised with COVID-19 – a retrospective study

Background: Various recommendations exist concerning the discontinuation of contact and droplet precautions (CDP) for patients hospitalised with coronavirus disease 2019 (COVID-19). Some are based on repeated negative real-time polymerase chain reaction (RT-PCR) results, whereas other are based on clinical criteria. The feasibility and safety of these recommendations are poorly documented. Method: We conducted a retrospective study to assess the feasibility and safety of a symptom-based strategy to discontinue CDP for patients hospitalised with COVID-19. We reviewed the clinical charts of all symptomatic patients hospitalised in our institution with RT-PCR-confirmed COVID-19 to assess the application of a symptom-based strategy for the implementation and discontinuation of CDP. The patients with discontinuation of CDP in accordance with the symptom-based strategy were cross-referenced with patients with potential hospital-acquired COVID-19 in order to assess the safety of this strategy. Results: Among the 147 patients included in our study, our symptom-based strategy was respected in 95 cases (64.6%). Discontinuation of CDP in accordance with the recommendations occurred in 39 patients (26.5%). After the discontinuation of CDP, patients remained hospitalised for a median time of 18 days, with exposure to a median number of three patients, resulting in a total number of 588 days ‘patient-day-exposition’. No hospital-acquired COVID-19 was detected in contact patients. Discussion: The use of a symptom-based strategy to discontinue CDP is applicable and safe. This symptom-based strategy was applicable regardless of patient’s age or COVID-19 severity.

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Is the Portable Chest Radiographic More Reliable to Reveal Covid19 in Highly Suspicion Patient before Real-Time Reverse Transcription Polymerase Chain Reaction (RT-PCR) Test?

International Journal of Innovative Research in Medical Science ◽

10.23958/ijirms/vol06-i03/1085 ◽

2021 ◽

Vol 6 (03) ◽

pp. 228-236

Author(s):

Bushra A. A. Albazi ◽

Dr Noof. Albaz ◽

Dr Nayef. Alqahtani ◽

Dr. Angham Salih ◽

Dr Rafat Mohtasab

Keyword(s):

Polymerase Chain Reaction ◽

Retrospective Study ◽

Predictive Value ◽

Rt Pcr ◽

Chain Reaction ◽

X Ray ◽

Polymerase Chain ◽

Rate Type ◽

Test Result ◽

Pcr Test

A large number of patients with coronavirus disease 2019 (COVID-19) present at hospitals. There are a limited number of isolation rooms open, and patients must often wait a long time to get a reverse transcription-polymerase chain reaction (RT-PCR) test done. This necessitates the introduction of effective triage plans. A patient with suspicions is referred to an emergency room (ED) depending on their medical record for a simple physical assessment, blood test findings, and chest imaging.A retrospective study design was conduct at Prince Sultan Medical Military City (PSMMC). Ethical approval was obtained from the institutional board to wave the consent forms since it is a retrospective study. Only the primary investigator has had the data access to the patients’ medical records. The collected patient records were under specific categories, including symptoms score starts from 5 and above, RT-PCR test result done after CXRP imaging, the patient admitted to the emergency department (ED). Excluding all CXRP done after RT-PCR TEST, positive Covid 19 admitted to the intensive care unit (ICU), pediatric patients, and patients with score symptoms were less than five. Two experienced radiologists reviewed the images blindly, and the inter-observer reliability of observations noted by the radiologists was calculated. As for the relationship between the x-ray reading and the RT-PCR test result, our results showed a high correlation between the variables (chi-square χ² = 12.44, with df =1, and p<0.001). The sensitivity of x-ray diagnosing covid19 was 65.52 %, while the specificity was 54.51 %, and the accuracy of radiologists reading was 58.17 %. Furthermore, the positive predictive value (PPV) was 41.76 %, and the negative predictive value (NPV) was 76.05%. Finally, the false positive rate (type-i error (alpha) was 45.49%, and the false-negative rate (type-ii error (beta) was 34.48% Our research findings show that CXRP imaging can detect COVID-19 infection in symptomatic patients and can be a valuable addition to RT-PCR testing. In an inpatient ED environment where availability of test kits, laboratory equipment, and laboratory personnel is compromised and risks delaying patient treatment and hospital workflow, serial CXRP could theoretically be used as an adjunct diagnostic function and monitoring in patients suspected of having COVID-19.

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Characteristics of recovered COVID-19 patients with recurrent positive RT-PCR findings in Wuhan, China: a retrospective study

BMC Infectious Diseases ◽

10.1186/s12879-020-05463-z ◽

2020 ◽

Vol 20 (1) ◽

Cited By ~ 1

Author(s):

Tie-Jun Shui ◽

Chao Li ◽

Hong-bing Liu ◽

Xiaohua Chen ◽

Bi-ke Zhang

Keyword(s):

Polymerase Chain Reaction ◽

Retrospective Study ◽

Clinical Characteristics ◽

Throat Swab ◽

Antibody Detection ◽

Controlled Trials ◽

Rt Pcr ◽

Chain Reaction ◽

Polymerase Chain

Abstract Background Two months after the outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, China, tens of thousands of hospitalized patients had recovered, and little is known about the follow-up of the recovered patients. Methods The clinical characteristics, reverse transcriptase-polymerase chain reaction (RT-PCR) results from throat swab specimens and the results of serological COVID-19 rapid diagnostic test (RDT) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were retrospectively reviewed for a total of 758 recovered patients who were previously hospitalized in 17 hospitals and quarantined at 32 rehabilitation stations in Wuhan, China. Results In total, 59 patients (7.78%) had recurrent positive findings for COVID-19 on RT-PCR from throat swabs. With regard to antibody detection, 50/59 (84.75%) and 4/59 (6.78%) patients had positive IgG or dual positive IgG/IgM RDT results, respectively. Conclusions Some patients who had been quarantined and had subsequently recovered from COVID-19 had recurrent positive RT-PCR results for SARS-CoV-2, and the possibility of transmission of the virus by recovered patients needs further investigation. Trial registration Current Controlled Trials ChiCTR2000033580, Jun 6th 2020. Retrospectively registered.

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1504: Molecular Diagnosis and Staging of Prostate Cancer Using Clusterin in Real Time Reverse Transcription Polymerase Chain Reaction (RT-PCR)

The Journal of Urology ◽

10.1016/s0022-5347(18)33708-x ◽

2006 ◽

Vol 175 (4S) ◽

pp. 485-486

Author(s):

Sabarinath B. Nair ◽

Christodoulos Pipinikas ◽

Roger Kirby ◽

Nick Carter ◽

Christiane Fenske

Keyword(s):

Prostate Cancer ◽

Polymerase Chain Reaction ◽

Real Time ◽

Molecular Diagnosis ◽

Reverse Transcription ◽

Rt Pcr ◽

Chain Reaction ◽

Polymerase Chain

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Polymerase chain reaction amplification and typing of rotavirus in environmental samples

Water Science & Technology ◽

10.2166/wst.1995.0643 ◽

1995 ◽

Vol 31 (5-6) ◽

pp. 371-374 ◽

Cited By ~ 5

Author(s):

R. Gajardo ◽

R. M. Pintó ◽

A. Bosch

Keyword(s):

Polymerase Chain Reaction ◽

Environmental Samples ◽

Polymerase Chain Reaction Amplification ◽

Rt Pcr ◽

Chain Reaction ◽

Pcr Assay ◽

Group A ◽

Reaction Amplification ◽

Stool Specimens ◽

Polymerase Chain

A reverse transcription polymerase chain reaction (RT-PCR) assay is described that has been developed for the detection and serotyping of group A rotavirus in stool specimens and concentrated and non-concentrated sewage specimens.

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Machine Learning Prediction of SARS-CoV-2 Polymerase Chain Reaction Results with Routine Blood Tests

Laboratory Medicine ◽

10.1093/labmed/lmaa111 ◽

2020 ◽

Author(s):

Thomas Tschoellitsch ◽

Martin Dünser ◽

Carl Böck ◽

Karin Schwarzbauer ◽

Jens Meier

Keyword(s):

Machine Learning ◽

Polymerase Chain Reaction ◽

Characteristic Curve ◽

Cohort Analysis ◽

Rt Pcr ◽

Chain Reaction ◽

Blood Tests ◽

Routine Blood ◽

Machine Learning Model ◽

Polymerase Chain

Abstract Objective The diagnosis of COVID-19 is based on the detection of SARS-CoV-2 in respiratory secretions, blood, or stool. Currently, reverse transcription polymerase chain reaction (RT-PCR) is the most commonly used method to test for SARS-CoV-2. Methods In this retrospective cohort analysis, we evaluated whether machine learning could exclude SARS-CoV-2 infection using routinely available laboratory values. A Random Forests algorithm with 1353 unique features was trained to predict the RT-PCR results. Results Out of 12,848 patients undergoing SARS-CoV-2 testing, routine blood tests were simultaneously performed in 1528 patients. The machine learning model could predict SARS-CoV-2 test results with an accuracy of 86% and an area under the receiver operating characteristic curve of 0.90. Conclusion Machine learning methods can reliably predict a negative SARS-CoV-2 RT-PCR test result using standard blood tests.

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A meta-analysis of accuracy and sensitivity of chest CT and RT-PCR in COVID-19 diagnosis

Scientific Reports ◽

10.1038/s41598-020-80061-2 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Fatemeh Khatami ◽

Mohammad Saatchi ◽

Seyed Saeed Tamehri Zadeh ◽

Zahra Sadat Aghamir ◽

Alireza Namazi Shabestari ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Reverse Transcriptase ◽

Ct Scan ◽

Predictive Value ◽

Meta Analysis ◽

Chest Ct ◽

Rt Pcr ◽

Chain Reaction ◽

Polymerase Chain ◽

Chest Ct Scan

AbstractNowadays there is an ongoing acute respiratory outbreak caused by the novel highly contagious coronavirus (COVID-19). The diagnostic protocol is based on quantitative reverse-transcription polymerase chain reaction (RT-PCR) and chests CT scan, with uncertain accuracy. This meta-analysis study determines the diagnostic value of an initial chest CT scan in patients with COVID-19 infection in comparison with RT-PCR. Three main databases; PubMed (MEDLINE), Scopus, and EMBASE were systematically searched for all published literature from January 1st, 2019, to the 21st May 2020 with the keywords "COVID19 virus", "2019 novel coronavirus", "Wuhan coronavirus", "2019-nCoV", "X-Ray Computed Tomography", "Polymerase Chain Reaction", "Reverse Transcriptase PCR", and "PCR Reverse Transcriptase". All relevant case-series, cross-sectional, and cohort studies were selected. Data extraction and analysis were performed using STATA v.14.0SE (College Station, TX, USA) and RevMan 5. Among 1022 articles, 60 studies were eligible for totalizing 5744 patients. The overall sensitivity, specificity, positive predictive value, and negative predictive value of chest CT scan compared to RT-PCR were 87% (95% CI 85–90%), 46% (95% CI 29–63%), 69% (95% CI 56–72%), and 89% (95% CI 82–96%), respectively. It is important to rely on the repeated RT-PCR three times to give 99% accuracy, especially in negative samples. Regarding the overall diagnostic sensitivity of 87% for chest CT, the RT-PCR testing is essential and should be repeated to escape misdiagnosis.

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Evaluation of Sandwich Enzyme-Linked Immunosorbent Assay and Reverse Transcription Polymerase Chain Reaction for the Diagnosis of Foot-and-Mouth Disease

Intervirology ◽

10.1159/000517003 ◽

2021 ◽

pp. 1-6

Author(s):

Salman Khan ◽

Syed Asad Ali Shah ◽

Syed Muhammad Jamal

Keyword(s):

Polymerase Chain Reaction ◽

Viral Genome ◽

Foot And Mouth Disease ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

Chain Reaction ◽

Kappa Value ◽

Polymerase Chain ◽

Pcr Assays ◽

Level Of Agreement

Background: Foot-and-mouth disease (FMD) is an infectious and highly contagious disease of cloven-hoofed domestic and wild animals, causing heavy economic losses to the livestock industry. Rapid and reliable diagnosis of the disease is essential for the implementation of effective control measures. This study compared sandwich enzyme-linked immunosorbent assay (S-ELISA) and conventional reverse transcription polymerase chain reaction (RT-PCR) for the diagnosis of FMD. Methods: A total of 60 epithelial samples from suspected cases of FMD were tested using both S-ELISA and RT-PCR assays. The level of agreement between the assays was assessed by calculating the Kappa value. Results: S-ELISA detected 38 (63%) samples positive for FMD virus (FMDV). Being predominant, serotype O was detected in 22 (57.9%) of the total samples tested positive, whereas 9 (23.7%) and 7 (18.4%) samples were found positive for serotypes A and Asia-1, respectively. RT-PCR detected viral genome in 51 (85%) of the samples using pan-FMDV primers set, 1F/1R. Thirty-six samples were found positive and 7 negative by both the tests. The level of agreement between the tests was assessed by calculating the Kappa value, which was found to be fair (Kappa value = 0.303 and 95% CI = 0.089; 0.517) and significant (p = 0.009). However, 2 samples, which were found positive on S-ELISA tested negative on RT-PCR. This may be attributed to the presence of nucleotide mismatch(es) in the primer-binding sites that may have resulted in failure of amplification of the viral genome. The serotype-specific RT-PCR assays not only confirmed serotyping results of S-ELISA but were also able to establish serotype in 9 S-ELISA-negative but pan-FMDV RT-PCR-positive samples. Conclusions: The RT-PCR assay contributes significantly to establishing a quick, sensitive, and definitive diagnosis of FMD in resource-constrained countries. Samples giving negative results in S-ELISA should be tested in RT-PCR for the disease detection and virus typing.

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Detection of specific mRNAs in single nephron segments by use of the polymerase chain reaction

AJP Renal Physiology ◽

10.1152/ajprenal.1990.258.5.f1470 ◽

1990 ◽

Vol 258 (5) ◽

pp. F1470-F1474 ◽

Cited By ~ 4

Author(s):

T. Moriyama ◽

H. R. Murphy ◽

B. M. Martin ◽

A. Garcia-Perez

Keyword(s):

Polymerase Chain Reaction ◽

Aldose Reductase ◽

Collecting Duct ◽

Specific Gene ◽

Rt Pcr ◽

Chain Reaction ◽

Nephron Segments ◽

Single Nephron ◽

Specific Mrnas ◽

Polymerase Chain

We have developed a procedure to detect specific mRNAs in single renal nephron segments. This approach combines microdissection, reverse transcription (RT) of the target mRNA, and amplification of the resulting cDNA using the polymerase chain reaction (PCR). After microdissection, the sample is placed in a tube where it is permeabilized and where all reactions are performed directly without the need for isolation of the RNA. Our model target was the mRNA for aldose reductase. This enzyme catalyzes the conversion of glucose to sorbitol. Its expression is modulated by changes in extracellular osmolality in the renal medulla. RT-PCR of inner medullary collecting duct (1 mm) and glomeruli (6-10) yielded a product of the predicted length (670 base pairs) defined by the PCR primers. Its identity was confirmed by a specific oligonucleotide probe that differed from the primers. RT-PCR of proximal tubules (1 mm) resulted in no aldose reductase-specific amplification product. RT-PCR is generally applicable for measuring specific gene expression in single nephron segments or small numbers of cultured cells. Utility, limitations, and refinements of this approach are discussed.

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Expression of hyaluronan synthase-3 in porcine oviducal epithelium during oestrus

Reproduction Fertility and Development ◽

10.1071/rd02100 ◽

2003 ◽

Vol 15 (2) ◽

pp. 99 ◽

Cited By ~ 22

Author(s):

Paisan Tienthai ◽

Naoko Kimura ◽

Paraskevi Heldin ◽

Eimei Sato ◽

Heriberto Rodriguez-Martinez

Keyword(s):

Polymerase Chain Reaction ◽

Reverse Transcription ◽

Hyaluronan Synthase ◽

Critical Periods ◽

Rt Pcr ◽

Chain Reaction ◽

Mean Values ◽

Polymerase Chain ◽

Sperm Reservoir ◽

Oviduct Fluid

Hyaluronan (HA) has been related to fertilization and embryo development in the pig. Furthermore, HA is present in pig oviduct fluid and the lining epithelium, particularly of the pre-ovulatory sperm reservoir. Because the mechanisms that regulate HA synthesis have not yet been clarified, semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) was conducted to assess the expression of mRNAs of two HA-synthesizing enzymes (has2 and has3) in the oviduct epithelium (uterotubal junction, isthmus, ampullary–isthmic junction and ampulla segments) of non-inseminated (control) and inseminated (treatment) sows at pre-, peri- and post-ovulatory oestrus. Only has3 mRNA was detected; it was present in all tubal segments of both control and treatment samples. The level of has3 expression did not vary significantly between non-inseminated and inseminated specimens, but there was a tendency (NS) for increased mean values during the peri- and post-ovulatory stages compared with pre-ovulation. It is concluded that has3 is expressed by the porcine endosalpinx epithelium and the levels of expression do not vary during the critical periods of sperm transport and fertilization, despite fluctuating levels of HA in the tubal fluid at corresponding periods.

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