Preparation of national reference panel of HBV for nucleic acid testing donor screening / 中国生物制品学杂志

@#Objective To prepare the national reference panel of hepatitis B virus(HBV) for nucleic acid testing(NAT)donor screening.Methods A number of plasma samples from donors positive for HBV antibody and patients with HBV infection collected from blood centers,plasma stations and biological products companies in Shanghai,Gansu,Henan,Hunan,Hubei and other regions were tested for HBV DNA viral load agent,and negative and positive reference candidates were screened;The HBV DNA national standard was diluted to 10~3 IU/ml with human negative plasma,as a candidate for limit of detection(LOD).National negative and positive reference candidates of HBV for NAT donor screening and LOD reference to be calibrated were distributed to 8 enterprise laboratories for joint detection of HBVHCVHIV NAT donor screening.The homogeneity and stability of the national reference panel were investigated.Results A total of 8 negative samples with HBV viral load of 0 were screened as negative references and 9 positive samples with viral load of 10~3～10~4 IU/mL were used as positive references;One LOD reference was calibrated with WHO HBV DNA standard,and the virus content was 1.0 × 10~3 IU/ml.The national reference panel showed good stability and the homogeneity inspection met the requirements.Conclusion The national reference panel of HBV DNA for NAT donor screening was prepared,which provided a basis for the quality control and standardization of HBV DNA reagents for donor screening.

Application andevaluation of random quality control sampling in donor blood detetion by ELISA / 中国输血杂志

【Objective】 To evaluate the effectiveness of random quality control sampling in blood sample detetion by ELISA. 【Methods】 Blood samples of 5 mL specification of blood donors from our blood station from May to July 2022 were selected for routine operation on a fully automated sampler. J standard substances(3 mL specification) as daily samples were added to A1 well, H12 well and random wells of HBsAg, anti-HCV, anti-HIV, and -TP, and then placed in a fully automated enzyme immunoassay analyzer for testing. With random well quality control as the internal quality control judgment standard, 20 consecutive tests were conducted and were divided into A1 (well) group, H12 (well) group and random (well) group according to different well positions. Quality control maps were drawn using Levey-Jennings quality control chart with random group as the framework, and were compared with the quality control map of A1 well and H12 well results in the same day. 【Results】 The mean quality control levels of infectious indicators of blood transfusion in blood donors by ELISA were: HBsAg 3.87±0.28, anti-HCV 3.79±0.38, anti-HIV 3.64±0.30 and anti-TP 4.53±0.51. 【Comparison】 of HBsAg, anti-HCV, anti-HIV and anti-TP, between random group, A1 group and H12 group were HBsAg 3.87± 0.28 vs 4.09±0.30 vs 3.64±0.26, anti-HCV 3.78±0.37 vs 3.96±0.38 vs 3.63±0.38, anti-HIV 3.63±0.31 vs 3.82±0.32 vs 3.48±0.28 and anti-TP 4.51±0.51 vs 4.71±0.52 vs 4.36±0.51, The S/CO value of each indicator were H12 group<random group<Al group (P<0.05), and the mean quality control levels of random group were similar to each detection indicator (P>0.05) . Using random group as the quality control framework standard, 5 points in group A1 fell outside of +2s, and 1 point in group H12 fell outside of -2s, resulting in a total of 6 alarms. With the quality control substance placed in A1 well of the ELISA plate, the judgment of detection results of the entire ELISA plate could be inevitably affected, especially the last row of low concentration virus marker samples on the ELISA plate. 【Conclusion】 The application of random quality control sampling method in donor blood by ELISA is scientific and reasonable, which can reduce the systematic error caused by artificial setting of ELISA plate fixed well positions and can also discover edge effects that affect the detection results.

Progress and prospect of living donor liver transplantation / 中华消化外科杂志

With the increasing number of patients waiting for liver transplantation worldwide, the development of living donor liver transplantation can not only alleviate the shortage of donor liver, but also expand the donor pool. Compared with classical liver transplantation, living donor liver transplantation is more complex and delicate in surgical operation, with many problems to be further discussed and solved. The authors retrospectively analyze relevant research results, combined with clinical practice, investigate the selection and evaluation of donor, selection of donor liver, surgical innovation and treatment of hepatocellular carcinoma in living donor liver transplan-tation, in order to provide helps for alleviating the shortage of donor liver and improving the prognosis of recipients.

Performance evaluation of HBsAg screening before blood donation in Dalian / 中国输血杂志

【Objective】 To improve the efficiency and screening strategy by evaluating the performance of HBsAg screening before blood donation in Dalian. 【Methods】 The confirmed HBsAg positive samples were detected qualitatively and quantitatively, and retested with HBsAg rapid testing kit pre-donational used parallelly. Efficiency of HBsAg screening before donation was calculated, and compared between first-time and repeated donors. 【Results】 The pre-donation HBsAg screening was conducted for 199 553 cases, including 95 321 first-time donors (63.2%) and 55 396 repeated donors(36.8%).1 015 donors (first-time/repeated: 999/16) were reactive in HBsAg rapid testing. 113 samples (first-time/repeated: 108/5), initially negative in HBsAg rapid testing, were confirmed HBsAg positive by laboratory testing. The efficiency of pre-donation HBsAg screening for first-time donors(10.9‰) was significantly higher than that of repeated donors(0.3‰)(P130) and 92.44 (18.7->130), respectively. 【Conclusion】 The HBsAg rapid testing kit used in Dalian Blood Center could meet requirements for blood donor screening before donation, while good efficiency of HBsAg pre-donation screening could be achieved only in first-time blood donors.

Nucleic acid amplification test: Bridging the gap in blood safety & re-evaluation of blood screening for cryptic transfusion-transmitted infection among Indian donors

Background & objectives: Nucleic acid amplification test (NAT) in blood donor screening not only detects window period (WP) donors but also those with chronic occult infections which are negative by routine serological screening. This study was conducted to determine the time trend of NAT positivity and seroprevalence of transfusion-transmitted infections (TTIs) through a period of six years and evaluate the strength of NAT as a supplementary test in identifying the cryptic carriers in blood donor population. Methods: A total of 1,01,411 blood donations were screened between January 2011 and December 2016 by the ELISA and individual donor (ID) NAT Procleix Ultrio Plus Assay. Additional molecular and serological assays were done on the NAT yield samples to differentiate the type of cryptic carriers. Results: NAT yields comprised 0.05 per cent (50/101411) of the total samples tested with a yield rate of 1/2028. Hepatitis B virus (HBV) contributed to 80 per cent of the total NAT yields and the rest 20 per cent due to hepatitis C virus (HCV). Majority of HBV NAT yields (75%) were from chronic occult donors and 25 per cent were WP donors. Both HBV and HCV NAT yields had a wide range of viral count. There was no HIV NAT yield. A significant decline in the prevalence rate of TTIs through the study period of six years was observed. Interpretation & conclusions: The cryptic infections found in blood donors increase the risk of TTIs. Blood screening by both serology and NAT can reduce this threat.

Strategies to Prevent Transfusion-Transmitted Infection in Blood Centers / 대한수혈학회지

There has been continuous effort to prevent transfusion-transmitted infection (TTI). Strategies to prevent TTI can be divided into two components: first, determining donor eligibility, and second, managing bacterial contamination of blood products. To determine donor eligibility, medical history taking and screening tests for infectious diseases should be performed. To prevent bacterial contamination, blood collection process should be aseptic, tests for bacterial detection should be performed, and an application of pathogen reduction technology should also be considered. In this review, screening test items and methods, including nucleic acid amplification tests for determining donor eligibility, and precautions for blood collection, bacterial detection methods, and pathogen reduction technology for the prevention of bacterial contamination of blood products were discussed in detail.

Results of Proficiency Tests for HBsAg and Anti-HCV as the Blood Donor Screening Testing (2012~2015) / 대한수혈학회지

BACKGROUND: Donor screening test is one of the most important processes for blood safety management. Korea Center for Disease Control and Prevention (KCDC) has been conducting an annual proficiency test program that includes the distribution of specially manufactured panels for hepatitis B surface antigen (HBsAg) and antibody to hepatitis C virus (anti-HCV) to blood centers. Here, KCDC reports the results of these proficiency tests for HBsAg and anti-HCV blood donor screening for all licensed blood centers in Korea between 2012 and 2015. METHODS: Panels for the proficiency tests were manufactured and distributed to blood centers by Chung-Ang University Hospital, which has been participating in the Korea Blood Safety Commission. Well-proven reactive sera and healthy donor's sera acquired from the Human Serum Bank in Chung-Ang University were used to make the panels. To identify the S/CO ratio of the panel, three medical institutes triple-checked the results of each panel. RESULTS: Most blood centers reported correct answers for the proficiency test with six panels. The average percentages (year) of correct answers were as follows: 98.7% (2012), 98.5% (2013), 99.1% (2014) and 99.6% (2015) for the HBsAg proficiency tests; and 97.7% (2012), 99.5% (2013), 99.1% (2014), and 99.8% (2015) for the anti-HCV proficiency tests. CONCLUSION: To improve the blood center's ability for donor screening tests, KCDC will continue the proficiency test program by managing specialized panels for HBsAg and Anti-HCV tests. Furthermore, we will investigate the level of satisfaction to improve the quality of the program.

Seroprevalence of Trypanosoma cruzi in blood donors at the National Blood Transfusion Services: Guyana / Seroprevalencia del Trypanosoma cruzi en los donantes de sangre en el Servicio Nacional de Transfusión de Sangre en Guyana

INTRODUCTION: Blood transfusion is an important transmission route of Trypanosoma cruzi (T cruzi), a major parasitic infection in Central and South America. The limited treatment options are most effective in acute Chagas' infection. At present, there is no current data on the prevalence of T cruzi in the blood donor population of Guyana. This information is necessary to protect the supply of the blood donation programme. This study sought to determine the prevalence of T cruzi in the blood supply at the National Blood Transfusion Services of Guyana with the hope of providing knowledge to the on-going surveillance for Chagas' disease worldwide and therefore address the risk of its spread by blood transfusion. METHODS: Two commercialized ELISAs utilizing crude or recombinant T cruzi antigens were used to study 2000 blood samples voluntarily donated for the purpose of altruistic or family replacement donation retrospectively. RESULTS: The results showed that approximately 1 in 286 donations tested positive for antibodies to T cruzi. CONCLUSION: These results indicate that T cruzi continues to be a risk in Guyana and there is a need to continue screening donated blood. Trypanosoma cruzi is a life-long infection and infected persons may be asymptomatic chronic carriers of the disease. Education, housing improvement, and controlled use of insecticides should be introduced to contain Chagas' disease.

INTRODUCCIÓN: La transfusión de Sangre es una vía de transmisión importante del Trypanosoma cruzi (T cruzi), una infección parasitaria mayor en América Central y América del Sur. Las opciones de tratamiento limitadas son más eficaces en los casos de la enfermedad de Chagas aguda. En el presente, no existen datos actualizados acerca de la prevalencia del T cruzi en la población de donantes de sangre en Guyana. Esta información es necesaria para proteger el suministro del programa de donación de sangre. Este estudio se propuso determinar la prevalencia de T cruzi en el suministro de sangre de los Servicios Nacionales de Transfusión de Sangre en Guyana, con la esperanza de aportar conocimientos a la vigilancia que tiene lugar en relación con la enfermedad de Chagas a nivel mundial, y por consiguiente aborda el riesgo de la difusión de esta última mediante la transfusión de sangre. MÉTODOS: Dos inmunoensayos ELISA con antígenos de T cruzi crudos o recombinantes, fueron utilizados a fin de estudiar 2000 muestras de sangre donadas voluntariamente a modo de donaciones altruistas o de reposición familiar, retrospectivamente. RESULTADOS: Los resultados mostraron que aproximadamente 1 de 286 donaciones daban positivo a anticuerpos frente al T cruzi. CONCLUSIÓN: Estos resultados indican que el T cruzi sigue siendo un riesgo en Guyana, y hay necesidad de continuar tamizando la sangre donada. El Trypanosoma cruzi es una infección crónica, y las personas infectadas pueden ser portadores asintomáticos crónicos de la enfermedad. Deben introducirse medidas en cuanto a educación, mejoramiento de las viviendas, y uso controlado de insecticidas, a fin de detener la enfermedad de Chagas.

Prevalence of hepatitis B & hepatitis C virus infections in potential blood donors in rural Vietnam.

Background & objectives: Safe blood and blood products should be offered to all patients in need for blood transfusion. The objectives of the present study were to establish prevalence estimates for hepatitis B and hepatitis C virus infections as a foundation for safe blood transfusion in rural Vietnam, and to check the accuracy of the laboratory analysis used for hepatitis testing of blood donors in Vietnam. Methods: A cross-sectional study was conducted in two rural communities in Quang Tri, Vietnam. A total of 1,200 blood samples collected from potential blood donors were tested by an enzyme immunoassay technique (EIA) for detection of hepatitis surface antigen (HBsAg), antibodies to hepatitis B core antigen (anti-HBc), and antibodies to hepatitis C antigen (anti-HCV). The EIA test outcome was validated by a chemiluminescent micro particle immunoassay technique (CMIA). Results: The prevalence of HBsAg and anti-HBc in the study population was 11.4 per cent (95% CI 9.6 - 13.2) and 51.7 per cent (95% CI 48.8 - 54.5), respectively, the prevalences being higher in males than females. The prevalence of anti-HCV was 0.17 per cent. The test agreement between the EIA and CMIA techniques was high both for HBsAg detection (κ = 0.91; 95% CI: 0.83 - 0.99) and for anti-HBc detection (κ = 0.89; 95% CI 0.81 - 0.97). Compared to CMIA results, the positive and negative predictive values of the EIA tests were found to be 94.9 per cent (95% CI 87.5 - 98.6) and 97.5 per cent (95% CI 86.8 - 99.9) for HBsAg, and 92.4 per cent (95% CI 84.2 - 97.2) and 100 per cent (95% CI 91.2 - 100) for anti-HBc. Interpretation & conclusions: The study shows that hepatitis B virus infection is endemic in rural areas of Vietnam and that almost half of the population is or has been infected. Hepatitis C infection is rare, but false negative test results cannot be ruled out. Also, the results indicate that the EIA performance in blood donor screening in Vietnam may be sub-optimal, missing 2.5 per cent of hepatitis B virus carriers and falsely excluding more than 7 per cent of blood donors. As the prevalence of hepatitis B infection is high, occult hepatitis B infection may represent a threat to safe blood transfusion. Therefore, nucleic acid amplification testing for HBV should be considered for blood donor screening in Vietnam.

Prevalence of HIV among blood donors in a tertiary care centre of north India.

Background & objectives: India has the second highest HIV population in the world with about 2.5-3.0 million cases. HIV-2 cases among general and blood donor population have also been reported mostly from west and south India. This single centre study was carried out to observe the HIV-1 and HIV-2 prevalence among blood donors from north India. Methods: A total of 2,04,677 people were screened for the presence of HIV infection over the 11 year period (1999 to 2009). Till 2004, a third generation ELISA kit was used. From 2005 till January 2009 all tests were done using the fourth generation ELISA kit which detected the presence of HIV-1 P24 antigen and anti-HIV antibodies. From February 2009 onwards, the kits used were Genscreen ULTRA HIV Ag- Ab Assay. Results: A total of 506 (0.247%) donors were found to be repeat reactive for HIV. Of these, 486 (96%) donors tested using the Western blot were found positive for HIV-1 infection. Twenty (4%) donors showed a negative Western blot result, none of the donors were found reactive for HIV-2 infection. Interpretation & conclusions: The prevalence of HIV was 0.249 per cent among blood donors of north India. No HIV-2 case was found among the studied blood donor population indicating that it is not a threat currently.

Analysis of the Effectiveness of Blotting Assays for Donor Blood Screening / 대한수혈학회지

BACKGROUND: Immunoblot assays (IBAs) have been widely used to confirm the reactivity of immunoassay. However, indeterminate (ID) results have shown the limits for interpreting IBAs. There is some debate about the benefit of these assays. We assessed the actual status of the IBAs for the donor screening process and we proposed more available algorithms. METHODS: We analyzed the data from the blood information management system of the Korean Red Cross. This study was approved by the Institutional Review Board of the KRC. The analyzed data included the present condition of various utilities and the results of the IBAs in the world. RESULTS: The infectivity of the ID results in IBAs seemed not to be high, but the safety could not be assured. IBA for HTLV was used as a confirmatory test in many countries. Most of the eligible blood donors could be saved by IBAs. CONCLUSION: IBAs seem to be valuable methods as supplemental and follow up tests for ID results. Furthermore, IBAs were useful to distinguish eligible blood donors. When donors show positive results on an immunoassay and NAT (HIV and HCV) concurrently, then IBA does not seem to be required. Only a RIBA for HCV is recommended for the donors showing a S/CO ratio above 2.0 on immunoassay. The additional alternative immunoassay would be effective in the HTLV screening algorithm.

External Quality Assurance Survey for the Blood Donor Screening Tests Performed in 2010 / 대한수혈학회지

BACKGROUND: To prevent blood-borne infections and guarantee safe transfusion, we proposed a quality assurance program for donor screening tests, such as hepatitis B surface antigen (HBsAg) and anti-hepatitis C virus antibody (anti-HCV), by introducing external proficiency testing for the laboratories that perform donor screening tests. METHODS: The materials for external proficiency testing (PT) were prepared from the HBsAg Standard Panels and anti-HCV Reference Panels provided by the Korea Food and Drug Administration (KFDA), and the normal Human Serum was provided by the Serum Bank of the Korea National Research Resource Center. The external PT materials were sent to 83 laboratories that performed donor screening tests after evaluating their quality. RESULTS: The results of evaluating the quality of the PT materials were acceptable. All the laboratories receiving the materials answered with a 100% response rate. All the laboratories answered that they obtained positive results for the HBsAg Standard Panel E, H, I and J; however, one laboratory answered in the gray-zone and that lab had negative results for HBsAg Standard Panel C and G. Seventy laboratories (84%) and 42 laboratories (51%) among the total 83 laboratories answered they had positive results for HBsAg Standard Panel B and D, suggesting that many laboratories could not detect a low level of HBsAg. All 83 laboratories answered that they had concordant results for the external PT for anti-HCV. CONCLUSION: Donor screening laboratories can detect low levels of HBsAg and anti-HCV without any errors and the performance of the laboratories that could not detect low levels of HBsAg remains to be improved. Quality assurance program using external PT with materials that contain various genotypes and mutants should be conducted to maintain the quality of donor screening tests.

The Results of External Proficiency Tests to Prevent Transfusion-transmitted Virus Infection: There Is a Need for a Quality Assurance Program for Donor Screening Tests to Prevent Blood-borne Virus Infections / 대한수혈학회지

BACKGROUND: We analyzed the results of external proficiency tests for HBsAg, anti-HCV and anti-HIV, and these tests are currently used for blood donor screening in Korea. METHODS: The external proficiency testing (EPT) data was retrospectively collected from 2001 to 2009 from the Korean Association of Quality Assurance for Clinical Laboratories, and this association includes those institutes that have blood centers. The pooled patient sera or converted sera from the plasma were used for EPT. The year 2004 data includes the Recombinant HBsAg variant (Gly/Arg 145). RESULTS: A total 806 institutes participated in this evaluation. The average discordant rate for HBsAg, anti-HCV and anti-HIV in the blood centers was 0.2%, 0.6% and 1.0%, respectively for the years 2001~2009. For the HBsAg test, the discordant rate was less than 0.5% in 2009, yet there was a much higher rate (1.6~22.2%) in 2004 when using the recombinant HBsAg variant. CONCLUSION: HBV variants or low positive antigen or antibody titers were problematic in the current clinical laboratory, and so a systematic quality assurance program should be conducted with using control materials.

A Proposal for Developing a National Quality Assurance Program for Donor Bloodassays / 대한수혈학회지

BACKGROUND: Viral screening assays performed for blood donors are required to have high sensitivity because false negative results can lead to transfusion-transmitted infections. To minimize the number of false negative cases, a systematic quality assurance program is required to verify donor screening tests. METHODS: The current status of quality assurance (QA) for blood donor screening tests in Korea and other countries was reviewed. A quality assurance program using the national standards of the Korea Food and Drug Administration (KFDA) was done as a pilot study to evaluate both the need for such a program and the feasibility of such a program. RESULTS: Singapore had a national quality assurance programs for the anti-HIVdonor screening tests. In the United Kingdom, all laboratories use the NIBSC working standards as QA materials for the donors screening. Ninety-five % (84/80) of blood centers replied that they would participate in a national quality assessment program and 92% (84/77) of the blood centers also felt that an independent organization should be designated to operate the program. Quality control materials with a weak reactivity should be included in a quality assessment program for donor screening. CONCLUSION: We propose 2 models for a National Quality Assurance Program (NQAP). In the first model, an independent national reference laboratory (NRL) needs to be established that operates the national quality assurance program. The second model involves the integration of the national quality assurance program for donor screening into the External Quality Assurance Survey run by the Korean Association of Clinical Assurance for Clinical Laboratory (KAQACL) using the national standards.

Chagas' disease: an algorithm for donor screening and positive donor counseling

Classical serological screening assays for Chagas' disease are time consuming and subjective. The objective of the present work is to evaluate the enzyme immuno-assay (ELISA) methodology and to propose an algorithm for blood banks to be applied to Chagas' disease. Seven thousand, nine hundred and ninety nine blood donor samples were screened by both reverse passive hemagglutination (RPHA) and indirect immunofluorescence assay (IFA). Samples reactive on RPHA and/or IFA were submitted to supplementary RPHA, IFA and complement fixation (CFA) tests. This strategy allowed us to create a panel of 60 samples to evaluate the ELISA methodology from 3 different manufacturers. The sensitivity of the screening by IFA and the 3 different ELISA's was 100%. The specificity was better on ELISA methodology. For Chagas disease, ELISA seems to be the best test for blood donor screening, because it showed high sensitivity and specificity, it is not subjective and can be automated. Therefore, it was possible to propose an algorithm to screen samples and confirm donor results at the blood bank.

Os testes sorológicos clássicos utilizados na triagem de doadores de sangue são trabalhosos e subjetivos. O objetivo do presente trabalho é o de avaliar a metodologia imuno-enzimática (ELISA) e propor um algorítmo para doença de Chagas em bancos de sangue. Foram estudados 7999 doadores de sangue e/ou componentes cujas amostras foram testadas com o objetivo de tria-las sorologicamente para doença de Chagas utilizando hemaglutinação passiva reversa (RPHA) e imunofluorescência indireta (IFA). As amostras reativas em pelo menos uma destas metodologias, foram retestadas com reativos diferentes por RPHA, IFA e fixação de complemento (CFA). Esta estratégia nos permitiu criar um painel de 60 amostras com as quais tornou-se possível a avaliação do método imunoenzimático (ELISA). A sensibilidade da triagem dos doadores pelos métodos ELISA e IFA foi de 100%. A especificidade foi melhor para a metodologia imunoenzimática. O teste ELISA parece ser o ideal para triagem em bancos de sangue pois é altamente sensível, específico, não é subjetivo e pode ser automatizado. Desta forma, torna-se possível a formulação de um algorítimo a ser utilizado na triagem sorológica e confirmação de resultados em doadores de bancos de sangue.