Practical Laboratory Medicine最新文献

{"title":"Development of a rapid LFA test based on direct RT-LAMP for diagnosis of SARS-CoV-2","authors":"Negar Sadeghi ,&nbsp;Neda Shirazi ,&nbsp;Moein Dehbashi ,&nbsp;Bahareh Maleki ,&nbsp;William C. Cho ,&nbsp;Zohreh Hojati","doi":"10.1016/j.plabm.2024.e00437","DOIUrl":"10.1016/j.plabm.2024.e00437","url":null,"abstract":"<div><h3>Introduction</h3><div>In response to the rapid spread of the SARS-CoV-2 virus, we developed a rapid molecular approach to diagnose COVID-19 without the need for RNA extraction.</div></div><div><h3>Methods</h3><div>The study utilized two molecular methods, RT-qPCR and colorimetric RT-LAMP, to diagnose the RdRp and ORF8 genes, respectively, in oro-nasopharyngeal swabs. Due to the high sequence diversity of ORF8 in SARS-CoV and SARS-CoV-2, it has been identified as a suitable target for virus detection. The RT-LAMP method was also carried out directly on heat-treated swab samples. The strip tests were made using gold nanoparticles and combined with the RT-LAMP for further analysis.</div></div><div><h3>Results</h3><div>The results showed that the isothermal amplification method had a sensitivity of 95 % (95 % C.I.: 86.08 %–98.96 %) and a specificity of 75 % (95 % C.I.: 19.41 %–99.37 %). The RT-LAMP-LFA method was able to distinguish positive and negative samples with 100 % sensitivity (95 % C.I.: 91.96–100) and 77.27 % specificity (95 % C.I.: 54.63–92.18). This method only required heating swab samples for 10 min at 65 °C before the RT-LAMP reaction.</div></div><div><h3>Conclusion</h3><div>By utilizing the RT-LAMP in combination with the LFA, it is possible to diagnose SARS-CoV-2 rapidly without the need for RNA extraction. The entire process from sample collection to test interpretation takes only 75–90 min, and the results can be interpreted by untrained individuals with the naked eye. By employing the ORF8 gene as a diagnostic target and eliminating the need for RNA extraction, the direct RT-LAMP-LFA method achieves a significant breakthrough that was not previously reported.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"42 ","pages":"Article e00437"},"PeriodicalIF":1.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142573233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The measurement of immunosuppressive drugs by mass spectrometry and immunoassay in a South African transplant setting","authors":"Amy Strydom,&nbsp;Doreen Jacob,&nbsp;Taryn Pillay,&nbsp;Refeletse Malahlela,&nbsp;Sean Currin","doi":"10.1016/j.plabm.2024.e00440","DOIUrl":"10.1016/j.plabm.2024.e00440","url":null,"abstract":"<div><h3>Objectives</h3><div>Liquid chromatography tandem mass spectrometry (LC-MS/MS) is the gold standard for measurement of immunosuppressive drugs (ISDs), but is technically demanding and less accessible in resource-limited countries. Immunoassays can also measure ISD concentrations, but may be limited by cross-reactivity. We evaluated the performance of the Roche electrochemiluminescence immunoassay (ECLIA) for cyclosporine, everolimus and sirolimus against LC-MS/MS in an African population for the first time.</div></div><div><h3>Methods</h3><div>Bias for ECLIA was estimated by comparing ECLIA-measured ISD concentrations to those obtained by LC-MS/MS in 42, 43 and 47 patient samples for cyclosporine, everolimus and sirolimus, respectively. Precision was assessed by performing replicate measurements of quality control materials.</div></div><div><h3>Results</h3><div>Deming regression analysis for all ISDs showed strong correlation between ECLIA and LC-MS/MS with a Pearson's r of &gt;0.94. The slopes for cyclosporine, everolimus and sirolimus were 0.94 [95 % CI: 0.87–1.03], 1.35 [95 % CI: 1.23–1.44] and 0.96 [95 % CI: 0.85–1.15] with y-intercepts of 31.60 μg/L [95 % CI: 2.02–57.63], 0.23 μg/L [95 % CI: 0.21 – 0.72] and 2.61 μg/L [95 % CI: 1.30–3.56], respectively. Difference plots showed a median bias of 2.07 % [95 % CI: 1.42 – 6.99 %], 41.2 % [95 % CI: 34.9–51.8 %] and 34.9 % [95 % CI: 28.4–47.3 %] for cyclosporine, everolimus and sirolimus, respectively.</div></div><div><h3>Conclusions</h3><div>The cyclosporine ECLIA yielded results comparable to LC-MS/MS while poorly comparable results were obtained for everolimus and sirolimus, which may be explained by ISD metabolite cross-reactivity, amongst other factors. The poor comparability, although not unique, is noteworthy and the clinical consequences of these differences require further investigation.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"42 ","pages":"Article e00440"},"PeriodicalIF":1.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142657875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Falsely abnormal serum protein electrophoresis after administration of intravenous immunoglobulins (IVIG): A retrospective cohort study","authors":"Andrew Sulaiman,&nbsp;Patrizio Caturegli","doi":"10.1016/j.plabm.2024.e00434","DOIUrl":"10.1016/j.plabm.2024.e00434","url":null,"abstract":"<div><div>Intravenous immunoglobulin (IVIG) therapy, used in several neurologic, hematologic, immunologic and dermatologic conditions, is known to interfere with the results of some serum laboratory tests. We analyzed the potential interference of IVIG on serum protein electrophoresis (SPEP) by reviewing more than a decade of SPEP studies performed by the clinical immunology laboratory of the Johns Hopkins Hospital. Of the total 100,350 SPEP performed between January 1, 2013 and December 31, 2023, 395 contained the keyword IVIG in the pathologist report, contributed by 348 patients confirmed to have received IVIG by chart review. Of the 348 patients, 20 (6 %) had a M-spike on SPEP suggestive of monoclonal gammopathy, while 328 (94 %) did not have it. Of the 20 patients, 14 received IVIG within 30 days from the SPEP collection date, while 6 received beyond 30 days. Serum immunofixation electrophoresis (SIFE) and clinical follow up showed no evidence of monoclonal gammopathy in 5 of the 14 patients. Overall, this 11-year retrospective cohort study showed that 5 of 348 (1.4 %) patients treated with IVIG and tested by SPEP had a false M-spike, that is a spike not confirmed to be caused by a monoclonal gammopathy by subsequent studies. Although small, the false positive rate of 1.4 % suggests that integrating knowledge of recent IVIG administration into the pathologist report would reduce SPEP misdiagnosis.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"42 ","pages":"Article e00434"},"PeriodicalIF":1.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142699313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Glycated albumin in pregnancy correlates negatively with body mass index and contributes to the risk of gestational diabetes mellitus","authors":"Toril Ø. Osestad ,&nbsp;Kristin Lilleholt ,&nbsp;Øyvind Skadberg ,&nbsp;Linda R. Sagedal ,&nbsp;Ingvild Vistad ,&nbsp;Thomas Hundhausen","doi":"10.1016/j.plabm.2024.e00439","DOIUrl":"10.1016/j.plabm.2024.e00439","url":null,"abstract":"<div><h3>Objectives</h3><div>The aims of our study were to establish a reference interval for glycated albumin (GA) in gestational week 30, to investigate whether GA can replace or reduce the need for oral glucose tolerance test (OGTT) in pregnancy, and to reassess the usefulness of body mass-index (BMI), age and fasting glucose in detection of gestational diabetes (GDM).</div></div><div><h3>Design</h3><div>and methods: We measured GA in 486 healthy pregnant women. Reference interval was calculated using the central 95 % of the results. ROC curves were created to assess the ability of GA, fasting glucose and BMI separately to detect GDM, and logistic regression analysis was used to estimate risk of developing GDM given the level of the same markers. Finally, multiple logistic regression analysis based on GA, fasting glucose and BMI was used to find a strategy of predicting a patient's risk of GDM.</div></div><div><h3>Results</h3><div>The reference interval for GA at week 30 of gestation is 6.8–10.3 %. The analysis has a low AUC (0.53) with respect to detecting GDM. It increases slightly to 0.64 when corrected for BMI, as GA is inversely correlated to BMI. Combining GA with fasting glucose and BMI at gestational weeks 16–20 could raise the AUC to 0.80.</div></div><div><h3>Conclusion</h3><div>GA cannot be recommended to replace OGTT for the diagnosis of GDM. Nor can it be used to identify women at risk of developing GDM. GA combined with fasting glucose and BMI in early pregnancy could be a useful model to estimate risk of GDM.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"42 ","pages":"Article e00439"},"PeriodicalIF":1.7,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142533309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel case of Hb Bart's hydrops fetalis following prenatal diagnosis: Case report from Huizhou, China","authors":"Zeyan Zhong ,&nbsp;Dina Chen ,&nbsp;Zhiyang Guan ,&nbsp;Guoxing Zhong ,&nbsp;Zhiyong Wu ,&nbsp;Jianmin Chen ,&nbsp;Jianhong Chen","doi":"10.1016/j.plabm.2024.e00438","DOIUrl":"10.1016/j.plabm.2024.e00438","url":null,"abstract":"<div><h3>Objective</h3><div>Presentation of a novel case of a patient with Hb Bart's hydrops fetalis, which was accurately identified by SMRT sequencing leading to expand the mutation spectrum of α-thalassemia.</div></div><div><h3>Case report</h3><div>A 26-year-old pregnant woman and her husband underwent molecular analysis of thalassemia due to abnormal hematological results. The molecular analysis showed that the pregnant woman carried -α^3.7/--^SEA, while her husband exhibited a negative result. Accordingly, the pregnant woman continued the pregnancy until the 19-week gestational age. She was subsequently referred to our department for genetic counseling due to abnormal ultrasound findings in the fetus. A novel deletional α-thal mutation was detected for the husband by MLPA, and the precise location of the mutation was determined through SMRT sequencing, which revealed a 45.2 kb deletion. Later, an interventional umbilical cord blood puncture was offered for the pregnant woman. The cord blood was subjected to capillary electrophoresis, which revealed apparent Hb Bart's and Hb Portland peaks associated with Hb Bart's hydrops fetalis syndrome.</div></div><div><h3>Conclusion</h3><div>It is imperative that Hb Bart's hydrops fetalis syndrome be diagnosed with the utmost expediency. If results of molecular analysis are not consistent with the clinical hematological findings, the presence of a novel thalassemia could be suspected. To identify the novel genotype, the SMRT sequencing represents an effective method for achieving an accurate diagnosis.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"42 ","pages":"Article e00438"},"PeriodicalIF":1.7,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142533310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of qPCR and chromogenic culture methods for rapid detection of group B streptococcus colonization in Vietnamese pregnant women","authors":"Manh-Tuan Ha ,&nbsp;Huyen Tran-Thi-Bich ,&nbsp;Thao Bui-Thi-Kim ,&nbsp;My-Linh Nguyen-Thi ,&nbsp;Thanh Vu-Tri ,&nbsp;Thuy-Duong Ho-Huynh ,&nbsp;Tuan-Anh Nguyen","doi":"10.1016/j.plabm.2024.e00435","DOIUrl":"10.1016/j.plabm.2024.e00435","url":null,"abstract":"<div><h3>Introduction</h3><div>Neonatal infections can rapidly become severe, with delays in treatment often proving fatal. <em>Streptococcus agalactiae</em> (Group B <em>Streptococcus</em>, GBS) is a common cause, typically transmitted from colonized pregnant women to neonates during childbirth. In Vietnam, routine prenatal care lacks standardized GBS screening protocols. This study aims to compare enhanced qPCR methods with the culture method, evaluate the diagnostic accuracy of these qPCR procedures, and assess the frequency of GBS infection in pregnant Vietnamese women during their final trimester.</div></div><div><h3>Materials and methods</h3><div>Pregnant women aged 35 weeks gestation or more were recruited. Rectovaginal swabs were collected and analyzed for GBS using chromogenic culture, a commercial real-time PCR kit, and in-house real-time PCR assays targeting the <em>cfb</em> and <em>sip</em> genes. Clinical diagnostic values were calculated, and GBS prevalence was determined.</div></div><div><h3>Results</h3><div>The study included 259 pregnant women with a mean age of 30.2 ± 5.0 years. Of these, 96.6 % had gestational ages of 37 weeks or more at delivery. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the <em>cfb</em>-based and sip-based qPCR assays were 94.1/92.7, 99.0/99.5, 97.1/98.5, 97.8/97.3, and 97.6 %, respectively. The Kappa values were excellent (0.940 and 0.939), with results available in under 2 h. GBS prevalence was 24.7 % and 25.5 % by <em>cfb</em>-based and <em>sip</em>-based qPCR assays, aligning with the culture method (25.5 %).</div></div><div><h3>Conclusions</h3><div>Both direct real-time PCR assays demonstrated high accuracy and were comparable to chromogenic culture in diagnosing GBS. A significant prevalence of GBS colonization was found among Vietnamese pregnant women in their final trimester.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"42 ","pages":"Article e00435"},"PeriodicalIF":1.7,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142445068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The interference and elimination of nitrite on determination of total urinary protein by Pyrogallol Red–Molybdate method","authors":"Shijian Fan ,&nbsp;Jiaqing Liu ,&nbsp;Yu Wei ,&nbsp;Jie Yao ,&nbsp;Juan Cheng ,&nbsp;Yang Tong ,&nbsp;Qiang Zhou ,&nbsp;Yuanhong Xu","doi":"10.1016/j.plabm.2024.e00436","DOIUrl":"10.1016/j.plabm.2024.e00436","url":null,"abstract":"<div><h3>Background</h3><div>Some urine samples showed negative values of total urinary protein by Pyrogallol red–molybdate (PRM) method. Interestingly, these samples showed notably high levels of nitrite in the urine dipstick test.</div></div><div><h3>Methods</h3><div>A total of 120 urine samples were collected and categorized into four groups (0 - &lt; 100, 100-&lt;500, 500-&lt;1000, ≥1000 mg/L) based on total urinary protein concentration. Various concentrations of nitrite (2, 10, 50, 100, and 200 mg/L) were added to urine samples to investigate potential interference of nitrite in total urinary protein measurement by the PRM method. Additionally, different concentrations of L-ascorbic acid (100, 500, 1000, and 2000 mg/L) were added to urine-nitrite mixtures to explore the possibility of reversing the interference effects.</div></div><div><h3>Results</h3><div>2 mg/L nitrite had no impact on the test results.10 mg/L nitrite only showed significant effects on the detection results among the groups with 0 - &lt; 100 and 100-&lt;500 mg/L (P &lt; 0.05). 200 mg/L nitrite caused a noticeable decrease in the urinary protein detection results of the four groups (0 - &lt; 100, 100-&lt;500, 500-&lt;1000, ≥1000 mg/L), and the concentrations were reduced to 2.7 %, 26.85 %, 75.22 %, and 89.33 % of their original levels, respectively. 500 mg/L L-ascorbic acid effectively eliminated the interference from 200 mg/L nitrite and almost had no effect on detection.</div></div><div><h3>Conclusions</h3><div>Nitrite had negative effect on the detection of total urinary protein by PRM method and L-ascorbic acid was effective in counteracting the interference caused by nitrite.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"42 ","pages":"Article e00436"},"PeriodicalIF":1.7,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142442029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validation of a LC-MS/MS assay for citric acid, cysteine and oxalic acid determination and its application to explore pre-analytical sample storage","authors":"Ying Shen ,&nbsp;Xia Luo ,&nbsp;Qing Guan ,&nbsp;Wenjie Lou ,&nbsp;Liming Cheng","doi":"10.1016/j.plabm.2024.e00433","DOIUrl":"10.1016/j.plabm.2024.e00433","url":null,"abstract":"<div><h3>Objectives</h3><div>Citrate, oxalate and cystine in 24-h urine are considered to be associated with the incidence and recurrence risk of urinary stone disease (USD). An evaluation of the LC-MS/MS kit for simultaneous quantification of the three analytes was undertaken.</div></div><div><h3>Design</h3><div>&amp; Methods: The analytical performance of the kit was investigated based on FDA, EMA and CLSI guidelines. To promote the standardization of sample storage, this kit has been applied to perform systematic pre-analytical stability study of these analytes in urine.</div></div><div><h3>Results</h3><div>This method was validated with good linearity with accuracy of 93.1%–104 %. Intra-day and inter-day imprecision were ≤5.55 % and 5.34 %, respectively. Recoveries of citrate, oxalate and cystine added to clinical samples were in the range of 92.0–103 %, 94.8–100 % and 99.0–107 % with CV ≤ 5.52 %. It was recommended that urine preserved with hydrochloric acid could be preferable in consideration of both reliable test results and neglected sample heterogeneity.</div></div><div><h3>Conclusions</h3><div>This kit is suitable for measurement of citrate, oxalate and cystine for understanding the etiology of urinary stones, and the proper storage of urine samples is crucial for the correctness of the test results.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"42 ","pages":"Article e00433"},"PeriodicalIF":1.7,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142424977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance evaluation of Eu3+-based CRP/SAA and PCT/IL-6 lateral flow immunoassay kits and their diagnostic value in respiratory tract infections","authors":"Mingxin Lin ,&nbsp;Jing Zhang ,&nbsp;Jianxing Cai ,&nbsp;Jumei Liu ,&nbsp;Min Zhu ,&nbsp;Ke Li ,&nbsp;Miaoyun Hu ,&nbsp;Chenxi Li ,&nbsp;Huiming Ye","doi":"10.1016/j.plabm.2024.e00432","DOIUrl":"10.1016/j.plabm.2024.e00432","url":null,"abstract":"<div><h3>Objectives</h3><div>Respiratory infections are among the most common infectious diseases, resulting in significant morbidity and mortality. C-reactive protein (CRP), serum amyloid A (SAA), procalcitonin (PCT), and interleukin-6 (IL-6) are advantageous for diagnosing respiratory tract infections. This study assessed the analytical performance and accuracy of new kits for Eu3⁺-based CRP/SAA and PCT/IL-6 lateral flow immunoassay and its diagnostic value in respiratory tract infections.</div></div><div><h3>Methods</h3><div>This study evaluated the detection performance of a test kit using guidelines from the Center for Medical Device Evaluation (CMDE) and the Clinical and Laboratory Standards Institute (CLSI). The test results were compared to those of the commercial kits (CRP: Mindray; SAA: Norman; PCT: Shanghai Upper; IL-6: Wantai BioPharm). A total of 156 patients with respiratory tract infections (53 with bacterial infections (Bac group); 50 with viral infections (Vir group); and 53 with co-infections (Bac + Vir group)) were enrolled, along with 50 healthy controls (HC group). Venous blood samples were collected to measure levels of SAA, PCT, CRP, and IL-6 using both the test and commercial kits. The diagnostic value of these biomarkers was assessed using receiver operating characteristic (ROC) curves.</div></div><div><h3>Results</h3><div>Correlation analysis demonstrated a strong concordance between the test kits and commercial kits (CRP: r = 0.9396, P &lt; 0.0001; SAA: r = 0.8986, P &lt; 0.0001; PCT: r = 0.9594, P &lt; 0.0001; IL-6: r = 0.9009, P &lt; 0.0001). The diagnostic performance of the test kits in identifying bacterial, viral, and co-infections was highly consistent with that of the commercial kit.</div></div><div><h3>Conclusions</h3><div>The Eu3⁺-based CRP/SAA and PCT/IL-6 lateral flow immunoassay test kits demonstrated high levels of consistency with commercial kits in terms of quantitative outcomes and diagnostic performance for respiratory tract infections.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"42 ","pages":"Article e00432"},"PeriodicalIF":1.7,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142357188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The potential relationship between EasyNAT system Tt values and Cobas z480 Ct values in the detection of SARS-Cov-2","authors":"Lu-Qing Zheng,&nbsp;Qing-Yong Wang","doi":"10.1016/j.plabm.2024.e00431","DOIUrl":"10.1016/j.plabm.2024.e00431","url":null,"abstract":"<div><h3>Objectives</h3><div>This study aimed to evaluate the potential relationship between the time threshold (Tt) values of a commercial EasyNAT system, which is based on cross priming amplification (CPA) technology, and the cycle threshold (Ct) values of the Cobas z480 analyzer, which is based on a real-time fluorescence polymerase chain reaction (PCR) method, in the detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) from oropharyngeal swabs. Design and Methods: Data were retrospectively collected from a clinical laboratory between December 4, 2022 and July 1, 2024.</div></div><div><h3>Results</h3><div>A total of 277 EasyNAT-positive samples (Tt values from 3.83 to 29.5) were simultaneously investigated using the Cobas z480 analyzer (Ct values from 10.74 to 38.78). The concordance rate between the two systems was 100 %. Among the positive samples, the mean and maximum PCR Ct values of O and N genes increased in line with increasing Tt values of the left and right amplification areas of the EasyNAT system. The maximum Ct values of the O or N gene determined by the Cobas z480 analyzer were no more than 29.52 when the Tt values of the left or right amplification areas of the UC0116 analyzer were no more than 6.</div></div><div><h3>Conclusions</h3><div>The safe, simple, fast, accurate, and automatic EasyNAT system used in conjunction with a PCR system might be a better choice for the detection of SARS-CoV-2 in hospitals, especially in settings without sophisticated PCR facilities. The Tt value (≤6) of the EasyNAT system can be a reference index for estimating the maximum Ct value (29.52) in SARS-CoV-2-positive samples.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"42 ","pages":"Article e00431"},"PeriodicalIF":1.7,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142425000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}