ABSTRACT
【Objective】 To investigate the effectiveness of current indicators in initial screening and retest before donation and access the optimal testing strategies. 【Methods】 Data of initial screening (rate method for ALT, colloidal gold method for HBsAg) and retest (rate method for ALT, ELISA for HBsAg) of 18 510 platelet donors in our center from January 2019 to December 2021 were collected, and the results were retrospectively analyzed and compared in terms of different years and number of donations. 【Results】 From 2019 to 2021, data of initial screening and retest of platelet donors were as follows: 1) the deferral rate of ALT and HBsAg was 12.98% (2 403/18 510) vs 0.26%(40/15 412); 2) the deferral rate of ALT was 13.19% (712/5 398) vs 0.20%(9/4 410)in 2019, 13.33% (873/6 549) vs 0.06%(3/5 387)in 2020 and 11.05% (725/6 563) vs 0.07%(4/5 615)in 2021; for initial screening, significant difference was noticed in ALT reactivity in 2021 as in comparison to other two years(P<0.05); 3) the reactive rate of HBsAg was 0.43% (23/5 398) vs 0.18%(8/4 410)in 2019, 0.66% (43/6 549) vs 0.20%(11/5 387)in 2020 and 0.41% (27/6 563) vs 0.09%(5/5, 615) in 2021. For initial screening, HBsAg deferral in 2021 was significantly different from 2019, while similar with 2020. 4) Among ALT deferral samples in the retest, 68.75% (11/16) were ALT≥45 U/L. Among HBsAg reactive samples, 91.67% (22/24) were reactive by single reagent. 【Conclusion】 Setting the threshold value of ALT for platelet donors in initial screening as less than 45 U/L can effectively reduce the reactive rate in the retest. HBsAg screening only for first-time platelet donors can reduce the detection cost. Adding pre-donation detection indicators according to local prevalence of transfusion transmitted diseases is conductive to reduce the discarding rate of platelets.
ABSTRACT
【Objective】 To evaluate the effectiveness of rapid initial screening using HBsAg and syphilis reagents of immunochromatography technology before blood donation, and explore the influencing factors. 【Methods】 The pre-donation screening of HBsAg and anti-TP and post-donation blood test results of blood donors in Yangzhou region from January 2020 to June 2023 were retrospectively analyzed. The HBsAg and anti-TP reactive samples by ELISA from January to June 2023 were, retested using colloidal gold immunochromatographic reagents, and the results were compared and analyzed. 【Results】 A total of 200 414 blood donors were screened, among which 781 were HBsAg and anti-TP positive, accounting for 0.39%. A total of 191 717 blood donors successfully donated blood, and 986 were HBsAg and anti-TP positive by ELISA, accounting for 0.51%. 62 HBsAg and 61 anti-TP reactive samples were retested using the initial screening reagent, with 24 HBsAg reactive samples and 26 anti-TP reactive samples, accounting for 38.71% and 42.62% respectively. 14 HBsAg and 6 anti-TP gray area samples were retested, but no reactivity was found.The reactivity rates of 9 samples with HBsAg detection S/CO values greater than 25.0 and 10 samples with anti-TP detection S/CO values greater than 15.0 were all 100%.There was a negative correlation between the reaction intensity (S/CO value) of reactive samples and interpretation time of initial screening reaction. 【Conclusion】 The rapid primary screening of hepatitis B and syphilis with immunochromatography technology among blood donors can effectively improve the quality of blood and the qualification rate of blood after collection. Through targeted training of primary screening staff, the quality of primary screening can be further improved, the rate of missed detection can be reduced, and costs can be saved, thus reducing the risk of transfusion transmitted infection and ensuring the health of blood donors.
ABSTRACT
【Objective】 To establish a routine screening method for unexpected antibodies of blood donors, analyze the results of centralized screening for unexpected antibody of blood donors in the blood center, and compare the cost of centralized and decentralized screening modes. 【Methods】 A total of 35 591 blood donors were screened for unexpected antibodies from March 31, 2021 to July 31, 2021, using microcolumn gel method. Unexpected antibody screening reactive samples were further confirmed by the Transfusion Research Institute of Shenzhen Blood Center, and the demographic characteristics were further determined through the analysis of unexpected antibody positive population. The direct cost and indirect cost of centralized and decentralized unexpected antibody screening mode were compared. 【Results】 Forty unexpected antibody positive samples were confirmed in Shenzhen, with the positive rate at 0.11%(40/35 591), among which MNS, Rh and Lewis system accounted for 35% (14/40), 32.5% (13/40) and 17.5% (7/40), respectively. Males and females accounted for 45% (18/40) and 55% (22/40), respectively (P0.05). Unexpected antibody screening in a centralized way saved about 1.16 million yuan per year. 【Conclusion】 It is necessary to carry out unexpected antibody screening for all blood donors, and centralized screening is more economical than decentralized screening.
ABSTRACT
【Objective】 To establish scrap indicators for key equipment in blood screening laboratory of blood centers and quantitatively assess the running status of key equipment, so as to provide a scientific method for equipment scrap. 【Methods】 Through the literature review and Delphi method, the scrap indicators of key equipment in blood screening laboratories were established in terms of applicability, economy and advancement of the equipment. The weights of relevant indicators were calculated by analysis hierarchy process (AHP), and the quantitative assessment model of equipment scrap priority was established according to the indicators and its weight. The equipment running data from January 2020 to December 2020 of Laboratory Department were collected and analyzed using the model, and its accuracy was verified based on experience. 【Results】 Thirteen second-level scrap indicators were established, and the weights of the three first-level indexes of applicability, economy and advancement were 0.582, 0.114 and 0.306, respectively. Among the total 30 key equipment, the model score of 4 equipment was less than 0.5, and the running status after manually checking met the scrap standard. 【Conclusion】 The model can accurately assess the scrap priority of key equipment and facilitate the procurement budget and scrapping identification in advance, which can avoid the waste of resources and ensure safe, efficient and orderly laboratory work.
ABSTRACT
【Objective】 To verify the detection performance of a newly introduced individual donation(ID) nucleic acid detection(NAT) system, and to confirm whether its main test parameters meet the expected requirements of blood screening. 【Methods】 Standard serum and plasma negative for HBV DNA, HCV RNA, and HIV RNA were diluted to different multiples samples (0.5~3 times) of the detection system′s limit of detection (LoD). These samples were conducted NAT test for HBV DNA, HCV RNA and HIV-1 RNA, to verify the testing sensitivity, stability, accuracy and anti-interference ability. 【Results】 The sensitivity of 3× LoD concentration of HBV DNA, HCV RNA and HIV-1 RNA was tested by the system, and the yielding rates were all 100%, with 1 ×LoD at 95.0%~100% and 0.5×LoD at 70.0%~90.0%. The intra-assay and inter-assay precision variation coefficient was 2.07%~2.62% and 2.33%~2.88%, respectively. The accuracy of 10 external quality assessment samples of National Center for Clinical Laboratories was 100%. Severe hemolysis and fatty blood had no effect on the detection of samples with 3×LoD concentration of HBV DNA, HCV RNA and HIV-1 RNA. Any combinations by samples with 2 × LoD concentration of HBV DNA, HCV RNA, and HIV-1 RNA were not inhibited by high concentrations of other viruses. Among 2 041 sero-negative samples from blood donor, the NAT yield of this system was 1.67% (34/2 041), which was a little bit higher than that of a imported minipool system (1.66%, 33/2 041) (P>0.05). 【Conclusion】 The ID-NAT system can meet the requirements in terms of sensitivity, stability, accuracy and anti-interference ability, and can be used for blood screening of blood donors.
ABSTRACT
【Objective】 To evaluate the residual risk of hepatitis C virus (HCV) in blood screening among voluntary blood donors in Zhengzhou. 【Methods】 The ELISA and NAT screening results of 497 171 voluntary blood donors in Zhengzhou from January 2019 to December 2020 were collected through the information management system of our blood center.The residual risk of HCV was assessed using the Prevalence-Window Period Residual Risk Model. 【Results】 The residual risk among repeated and first-time blood donors was 1∶132 280 (95% CI: 1∶95 520~1∶188 820) and 1∶44 090 (95% CI: 1∶31 840~1∶62 940), respectively. The overall residual risk of blood donors screening was 1∶68 540 (95% CI: 1∶65 910~1∶130 290). The reactive rate of HCV screening in first-time blood donors (0.144%, 334/231 168) was significantly higher than that in repeated blood donors (0.014%, 36/266 003) (P<0.05), and the reactive rate of repeated blood donors in 2019 (0.019%, 26/135 267) was significantly higher than that in repeat blood donors in 2020 (0.008%, 10/130 736) (P<0.05). 【Conclusion】 The residual risk of HCV among voluntary blood donors in Zhengzhou is low.The publicity and recruitment should be further strengthened to establish a stable team of voluntary blood donation, and health consultation and physical examination should also be strengthened to further reduce the residual risk of blood transfusion.
ABSTRACT
【Objective】 To investigate the situation of hepatitis E virus(HEV) infection among voluntary blood donors in Wuhan area and provide evidences for enhancing blood screening strategies. 【Methods】 HEV nucleic acid detection(NAT) was performed on blood samples from eligible blood donors in Wuhan from November to December 2020. The testing results were analyzed, and the blood donors with repeated reactive results were followed up to clarify the status of infection. 【Results】 Routine screening was performed on 17 409 blood samples from November to December 2020. A total of 17 322 blood samples of eligible blood donors were tested for HEV NAT, and one case of HEV RNA reactivity was detected. The results from the follow-ups showed that the blood donor should be in the window period of HEV seroconversion. The current HEV infection rate of voluntary blood donors in Wuhan arewas 0.058‰(1/17 322), which was lower than other domestic areas. 【Conclusion】 The current HEV infection rate of voluntary blood donors was at a relatively low prevalence level in Wuhan area. Selective blood screening strategies can be taken to further reduce potential risk of blood transfusion infection with hepatitis E virus.
ABSTRACT
【Objective】 To evaluate the performance of electrochemiluminescence immunoassay (ECLIA) in detecting HIV antigen/antibody in blood screening. 【Methods】 A total of 128 donors, reactive to anti-HIV(ELISA)testing, from September 2016 to September 2020 were enrolled, and seven samples were reactive to double anti-HIV reagents, among which 6 were confirmed by WB, 1 confirmed by NAT as negative.Two group of donors, reactive to solo anti-HIV reagent but being confirmed negative by WB(n=121) vs.randomly selected donors non-reactive to ELISA + NAT(June to September 2020, n=1360), were subjected to HIV antigen/antibody testing using ECLIA to compare the testing results, including concordance rate, sensitivity and specificity. 【Results】 The ECLIA results remained non-reactive for 1360 samples initially non-reactive to both ELISA and NAT.The concordance rate of anti-HIV reactivity by ECLIA and ELISA+ WB were 100%(6/6). For 122 samples, reactive to ELISA anti-HIV testing but nonreactive to confirmatory testing, 4(3.28%)of them were reactive to HIV antigen/antibody testing and 118(96.72%) nonreactive, with the concordance rate of ECLIA and ELISA at 96.88%(124/128). The sensitivity, specificity and false positive rate of ECLIA and ELISA were 100% vs 100%, 99.73% vs 91.77%, and 0.27% vs 8.23%, respectively. 【Conclusion】 ECLIA for HIV antigen/antibody detection has good sensitivity and specificity, which can meet the requirements of blood screening, and the false positive rate is lower than that of ELISA, adopted commonly in blood bank at present.
ABSTRACT
【Objective】 To analyze the cost-effectiveness of ELISA grey area strategy through establishing the health economics model. 【Methods】 The serological grey area strategy evaluation model was composed of screening strategy subdecision tree, pathogen infection subdecision tree and pathogen detection subdecision tree. The key parameters in the model were obtained from literatures and research data. The cost-effectiveness of setting ELISA grey area strategy was compared by software, and multifactor sensitivity analysis was conducted. 【Results】 After setting the ELISA grey area, extra samples(5.86 cases/100 000) with serological false negativity could be detected, including HBV samples at 4.93/100 000, HCV samples at 0.27/100 000, HIV samples at 0/100 000, syphilis samples at 0.66/100 000. To yield an additional seropositive sample out of every 100 000 blood donors, blood center will afford extra 1 million yuan about. 【Conclusion】 Through this study, a cost-effectiveness evaluation model of serological detection strategy was established. Although the ELISA grey area setting can yield a small number of seropositive samples, the cost is much higher than the current affordability.
ABSTRACT
【Objective】 To retrospectively analyze the unqualified blood screening results of voluntary blood donors in Guangzhou area during 2016~2020, and analyze various factors that affect the blood screening results, for the purpose of providing a scientific basis for recruitment and retention of blood donors, improving blood safety, and avoiding waste of blood resources. 【Methods】 A total of 1 548 204 voluntary blood donors in Guangzhou from 2016 to 2020 were selected as the research objects, and the blood samples were screened by dual ELISA and once NAT. The unqualified rate of different years and populations were counted and the analysis of risks of unqualified blood testing was performed by conditional Logistics regression. 【Results】 An overall unqualified rate of blood screening was 2.52% in Guangzhou from 2016 to 2020, the unqualified rate of every year showed a downward trend first and then an upward trend. HBsAg and ALT were the two primary deferral causes, the positive rate was 0.65%(10 129/1 548 204) and 1.22%(18 824/1 548 204), respectively; the unqualified rate in male blood donors3.10%(31 091/1 004 079) was significantly higher than that in female(P<0.05), and that in blood donors aged 18~25 was 1.84%(12 781/694 374), which was lower than the other three age groups (P<0.05). Fewer students(1.33%, 4 024/302 007) and bachelor degree donors(1.57%, 5 379/341 662) were deferred. Compared with individual blood donors, group blood donors’ deferral rate(2.62%, 21 307/813 664) was higher. The deferral rate of first-time blood donors(4.57%, 24 469/535 551) were higher than the repeated blood donors (P<0.05) , meanwhile, whole blood donors(2.84%, 38 111/1 340 678) higher than those apheresis donors (P<0.05). Gender, age, occupation, education, frequency and blood components donated were risk factors for unqualified blood screening. 【Conclusion】 The deferral rates of voluntary blood donors in Guangzhou showed an overall upward trend, from 2016 to 2022. HBsAg and ALT were the primary deferral causes, and there were differences in demographics and blood donation characteristics. To formulate targeted recruitment strategies according to the test results of voluntary blood donors, and strengthen the publicity of low-risk groups and the consultation and screening before blood donation, will be a great benefit for reducing the blood scrap and guaranteeing the blood safety.
ABSTRACT
【Objective】 To investigate the serological and molecular characteristics of HBsAg+ /HBV DNA non-reactive (NR) infections. 【Methods】 Samples tested as HBsAg+ and HBV DNA NR were confirmed by individual NAT repeat testing, viral particle concentration by PEG precipitation combined with in-house nested PCR and real-time quantitative PCR, anti-HBc testing, and HBsAg quantification. HBV sequences were compared with those from donors with chronic and occult infection as controls. 【Results】 A total of 792 195 samples were screened between January 2011 and December 2020, of which 53 (1: 14 947) were confirmed HBsAg+ /HBV DNA NR. HBV DNA was detected further in five (9.4%) samples; three S sequences and four Pre Core/Core sequences were obtained. Unique amino acid substitutions (P130T, P135Q/S, R151Q, G153S and S155F) were found in the Core protein that may affect virus packaging and replication. 【Conclusion】 Extremely low HBV DNA level was detected in plasmas of HBsAg+ /HBV DNA NR donors. Barely detectable HBV DNA might be associated with unusual mutations in the Pre Core/Core protein affecting viral replication. More sensitive HBV DNA and/or HBsAg assays may be considered to further reduce the potential HBV transfusion-transmission residual risk.
ABSTRACT
【Objective】 To investigate the confirmatory status of HIV-1 antibody detection and Western blot (WB) test among voluntary blood donors in Wuhu, and to explore the strategies and methods to further ensure blood quality and safety. 【Methods】 Blood samples were preliminarily screened by ELISA and NAT, and the reactive samples were sent to Wuhu CDC for further WB test of HIV-1 antibody. The confirmation results of HIV-1 antibodies of voluntary blood donors in Wuhu in the past 10 years were retrospectively collected. The characteristics of WB bands of positive samples were analyzed, and the demographic characteristics of HIV-infected voluntary blood donors were sorted out. 【Results】 A total of 354 864 blood samples from voluntary blood donors in Wuhu during January 2011 to May 2021 were investigated, among which 42 were confirmed HIV positive (HIV-1 antibody positive in 41, and solo HIV-RNA reactive in 1), with a total HIV positive rate of 11.8/100 000(42/354 864). Statistical differences were found in gender [males 97.6% (41/42) vs females 2.4% (1/42)], marital status [unmarried 17.3/100 000 vs married 8.0/100 000] and occupation [staff/workers 37.5/100 000 vs students11.4/100 000 vs others 7.7/100 000]. Among the positive samples, the yield rate of WB bands gp160 was 100% (41/41), both gp41 and p24 were 97.6% (40/41),, and p55 was the lowest 46.3% (19/41). P51 and P66 presented the highest yield consistency (Kappa=1.000, P5 000 cps/mL by viral load (VL) testing, indicating HIV window period infection. 【Conclusion】 HIV infection statistically affected male donors more than females in Wuhu area, and most were early infection that revealed by WB band analysis. NAT plays an important role in the detection and confirmation of HIV infection during the window period, and is essential for blood safety.
ABSTRACT
【Objective】 To retrospectively analyze the quality status and annual trend of provincial-level centralized blood screening across Ningxia, and discuss the effect and advantages of the application of centralized blood screening. 【Methods】 The centralized detection, with the combination of enzyme linked immunosorbent assay (ELISA) and nucleic acid test(NAT), in Ningxia from 2016 to 2020 was statistically analyzed, and the sample size, overall unqualified rate and unqualified rate of each item were compared among different regions. 【Results】 There were about 70 000 samples in Ningxia annually, 65% were in Yinchuan city, and 35% in Shizuishan, Wuzhong, Guyuan and Zhongwei city. The unqualified rates of blood screening in above five cities were 1.09% (2 438/223 852), 1.48% (401/27 024), 1.50% (425/28 364), 1.01% (351/34 772) and 1.45% (435/30 002) respectively. Significant differences were noticed in the unqualified rates of HBsAg, anti-HCV, anti-TP, HIV Ab/Ag, ALT and HBV DNA (P0.05) among the five cities. 【Conclusion】 Centralized blood screening at provincial-level in Ningxia can optimize the allocation of laboratory resources and better ensure blood safety, which is of great significance to the construction of urban public health system in Ningxia.
ABSTRACT
【Objective】 To assess the status of HCV infection by analyzing the results of anti-HCV reactive blood samples detected by the current blood testing strategy, and discuss the viability of classified management of reactive blood donors. 【Methods】 The anti-HCV reactive samples (dual ELISA and once NAT), from May 2017 to October 2018, were divided into three groups: samples both anti-HCV and HCV RNA reactive, sole HCV RNA reactive, and sole anti-HCV reactive, and all of them were confirmed by recombinant immunoblot assay (RIBA). The positive predictive value (PPV) between groups were compared. The sensitivity, specificity and PPV for each reagent under different screening threshold (screening threshold for routine detection, optimal screening threshold, and corresponding screening threshold of the highest PPV) were analyzed. The group with low PPV were stratified by ELISA S/CO values, and PPV by different screening threshold was compared. 【Results】 There were 939 reactive samples (0.49%, 937/191 627). Confirmed by RIBA, the positive rate of anti-HCV reactive samples was 10.67%(100/937). Two samples were sole HCV RNA reactive (0.001%). Both anti-HCV+ HCV RNA reactive samples were 6.71%(63/939), with the PPV of 96.83%(61/63). Sole anti-HCV reactive samples were 93.08(874/939), with the PPV of 4.46%(39/874), among which PPV by dual and one ELISA reagent were 18.72% and 0.15%, respectively, showing statistically significant difference (P<0.05). The PPV between different S/CO values was statistically significant (P<0.05). The optimal screening thresholds of anti-HCV reagent were 9.29 and 3.97, according to the ROC curve, with significant difference noticed in PPV by different screening threshold (P<0.05). PPV in the sole anti-HCV reactive group increased from 4.46% (the routine screening threshold) to 49.35%(the optimal screening threshold), and the difference was statistically significant (P<0.05). 【Conclusion】 The blood donors with both anti-HCV and HCV RNA reactive can be determined as HCV infection and need to be permanently deferred. The S/CO value of sole anti-HCV reactive samples was positively correlated with RIBA confirmation results, and the higher the S/CO value, the greater the chances of positive confirmation are. With the current blood screening strategy, the HCV infection status of sole anti-HCV reactive blood donors can be determined by establishing a screening threshold with high PPV or adding confirmatory test.
ABSTRACT
【Objective】 To perform electrochemiluminescence immunoassay (ECLIA) and Western blotting (WB) confirmation tests for HIV reactive samples in blood screening, and analyze the correlation between ELISA (enzyme-linked immunosorbent assay), ECLIA results and confirmed infection, so as to provide data support for the application of ECLIA in blood screening. 【Methods】 177 HIV reactive samples in blood screening testing detected by our laboratory from February to October 2019 were collected, of which 137 were reactiv to isolated ELISA reagent e, 39 to dual ELISA reagent, and 1 in window period. Ten maker-negative samples were randomly selected to undergo ECLIA with the above 177 samples. HIV reactive samples were sent to Centers for Disease Control and Prevention (CDC) for confirmation tests, and the results were analyzed and compared. 【Results】 Among the 177 HIV reactive samples, 66 were ECLIA reactive, 111 negative, and the 10 maker-negative samples remained negative. The sensitivity, specificity, positive predictive value, negative predictive value and total concordance rate of ECLIA were 97.1%, 81.1%, 55%, 99.1% and 84.2%, respectively, showing better performance than that of two ELISA reagents(P0.05). The positive predictive value and specificity were tested by chi-square test, and the difference between ECLIA and reagent 2 was statistically significant (P<0.05). The ECLIA results showed significant correlation with the confirmation results with good consistency(examed by Kappa test). Among the three reagents, ECLIA presented highest accuracy and largest Youden index. 【Conclusion】 ECLIA presents high detection sensitivity, which can improve the detection ability of early HIV infection and shorten the window period of HIV detection, therefore should be popularized in blood screening.
ABSTRACT
【Objective】 To evaluate the performance and clinical application of a high-throughput nucleic acid blood screening detection system for SARS-CoV-2, so as to provide basis and technical means for its application in detection of plasma from recovered COVID-19 patients. 【Methods】 The SARS-CoV-2 nucleic acid was detected by real-time fluorescence quantitative PCR, and the sensitivity, precision, anti-interference and other parameters were evaluated. Blood donor samples collected during COVID-19 epidemic period were screened using the detection system to evaluate its applicability. 【Results】 The detection limits of gene N and ORF 1ab were 3.98 copies/mL and 9.38 copies/mL, respectively. The CV of high and low concentration samples were both less than 5%. Hemoglobin at 500 mg/dL and triglyceride at 3g/dL had little effect on the results. The detection system can effectively prevent carryover, thus avoiding false positive results. The SARS-CoV-2 nucleic acid blood screening was carried out in a total of 39 306 blood samples, and all samples were negative. 【Conclusion】 The established method can meet the needs of SARS-CoV-2 nucleic acid screening therefore ensure the safe application of plasma from recovered COVID-19 patients.
ABSTRACT
【Objective】 To study the screening and confirmatory test of human T-lymphotropic virus(HTLV) in blood donors. 【Methods】 Anti HTLV-1 / 2 screening was conducted on voluntary blood donors from 9 cities in Fujian province betweenJan. 12016toDec. 312018.Plasma samples ofanti-HTLV-1/2 reactive donors werecollected and sent to Xiamen Blood Center for confirmatory test. The influence of different screening reagents and confirmatory test methods on the test results were analyzed. 【Results】 A total of 741 anti-HTLV-1/2 reactivesamples were collected, among which 252 were positiveby Western Blot, 15undetermined, and 474negative, withthe overall positive rate at 34.0% (252/741). The yielding rate of domestic reagent A was significantly differentbyregions, withthe highest in Ningde(73.9%, 88/119) and the lowest in Zhangzhou(4.0%, 4/99). The confirmedpositive rates of anti-HTLV-1/2 screening reagent A(domestic) and B(imported)were 33.3%(13/39) and 57.1%(56/98), respectively, and the difference was statistically significant(P5, the reagent Ayielding rate was 76.5%(13/17), significantly lower than that of imported reagent Bas 100%(56/56) (P<0.01). A total of 652 anti-HTLV-1 / 2 reactive samples were confirmed by Western Blot and nucleic acid test in parallel, among which 638 results were concordant, 14 were not, with the overall concordance rate at 97.85%. 【Conclusion】 Comparable differences in the yielding rate of twoanti-HTLV screening reagents were observed.There was over allhighconcordance, but also complementarity, between Western Blot and nucleic acid test.
ABSTRACT
【Objective】 To retrospectively analyse the quality status and annual trend of centralized blood screening across the regions of Hubei province, and discuss the effect and advantages of the application of centralized blood screening across blood establishment. 【Methods】 Blood screening results of five blood establishment across Hubei province from 2005 to 2019 were statistically analyzed. The sample size, overall rate of qualified blood donations, overall and annual rate of positive testing items were compared among regions. 【Results】 There were differences in blood quality among different regions of Hubei province. In Wuhan, Ezhou, Xiantao, Tianmen and Qianjiang, the overall rate of qualified blood donations was 97.1%(2 466 396/2 538 871), 96.5%(85 405/88 547), 95.2%(59 087/62 047), 95.5%(68 920/72 146) and 94.7%(34 274/36 188), respectively; the overall deferral rate of ALT was 1.472% (37 374/2 538 871), 2.024% (1 792/88 547), 2.840% (1 762/62 047), 2.476% (1 786/72 146) and 3.777% (1 367/36 188), with significant differences across regions; the overall positive rate of HBsAg was 0.587% (14 897/2 538 871), 0.664% (588/88 547), 1.094% (679/62 047), 1.282% (925/72 146) and 0.862% (312/36 188), with significant differences across regions. The deferral rate of ALT showed a downward trend by year in these five regions from 2005 to 2019.An decreasing trend in the seroprevalence of HBV was noticed in Wuhan, Tianmen, and Qianjiang, HCV in Wuhan, Ezhou, and Tianmen, as well as syphilis infections in Wuhan. 【Conclusion】 Centralized blood screening can optimize the allocation of testing resources, reveal problems during blood collection and supply and improve the ability to guarantee blood safety. Future efforts are needed to expand the scope of centralized blood screening and seek for a centralized screening mode suitable for local situation.
ABSTRACT
【Objective】 To verify the key performance parameters of Roche Cobas S201 multiplex NAT for blood donors, so as to provide data for the conformation of multiplex NAT performance and establish a scientific and feasible verification scheme. 【Methods】 Comprehensive performance verification on four key parameters of ROCHE COBAS S201 multiplex NAT system, including the 95% detection limit, compliance rate, anti-interference ability and operator comparison were conducted. The data were compared with the specifications provided by the manufacturer to evaluate the performance of laboratory testing system and ensure the quality of blood testing. 【Results】 2 sets of COBAS S201 multiplex NAT system in our laboratory were used to perform 5 times of the 95% detection limit value declared by the manufacturer for individual tests. The experimental results showed that the target NAT can be detected 100% and the lower limit of determination was verified. Single-virus NAT was performed to detect 5 different HBV DNA concentrations (25 ~400 IU/mL), 5 different HCV RNA concentrations (25 ~400 IU/mL), 5 different HIV RNA Concentration (100~1 000 IU/mL), and 5 negative tubes. The experimental results showed that all detected values of 20 tubes were 100% consistent with the true value, and the performance parameter "coincidence rate" was verified. Samples containing lipoemia, hemolysis, with ALT>50 mL/L and syphilis-positive endogenous interfering substances with 3 times of the 95% detection limit value were tested for 3 times, and results showed both response rate (3/3) and yielding rate reached 100%. In the control group (with none or in the normal range of interfering substances), reactivity was detected in samples with extremely low concentration of 3 times of the 95% detection limit, showing no significant difference (P>0.05). Above results fully showed that the existence of interference substances (lipidemia, hemolysis, ALT ≥ 50 and syphilis positive) in the blood of donors had no significant effect on the yielding of HBV/HCV/HIV virus target nucleic acids. Different operators performed the sample loading tests with same instrument, reagent and specimen showed 100% consistency in the results. It could be preliminarily assessed that there was no difference in the operations between the operators in this verification. 【Conclusion】 The verification scheme of the multiplex NAT system for methodology performance index (95% detection limit, coincidence rate, anti-interference ability, and operator comparison) established in this study, showed simple, flexible, scientific and feasible characteristics and could provide reference and data support for domestic blood transfusion services in acid detection.
ABSTRACT
【Objective】 Aim of this study was to evaluate performance of two chemiluminescence immunoassay (CLIA) reagents for hepatitis C virus antibodies (anti-HCV) detection, focusing on the feasibility of blood screening for blood donors. 【Methods】 The sero-panel samples from NCCL and the donor samples were tested with CLIA, ECLIA and two ELISA (A: double antigen sandwich method, B: indirect method) reagents synchronously to evaluate their performances respectively, and the sensitivity, specificity and CV of the four reagents were compared. 【Results】 CLIA, ECLIA, A and B reagents showed sensitivities of 99.06%(315/318), 99.69%(317/318), 99.06%(315/318) and 99.69%(317/318), and clinical specificities was 99.06%(315/318), 99.69%(317/318), 99.06%(315/318) and 99.69%(317/318), respectively. Between-run and within-run precision for ECLIA reagent ranged (both CV<8%) was better than two ELISA reagents (between-run: CV <15% and within-run: CV <20%), and the CLIA reagent also met the requirement in blood screening (CVs <14%). 【Conclusion】 This ECLIA reagent showed high sensitivity and good reproducibility together with acceptable specificity in routine sample screening, which proved its further application in blood screening. This CLIA reagent has high specificity and the same sensitivity as indirect ELISA reagent. This CLIA reagent could be used in combination with other reagents with high sensitivity to screen anti-HCV in blood donors.