Sample preparation and analysis of proficiency test containing Staphylococcus aureus with drug matrix / 上海预防医学

Objective To prepare samples of proficiency testing （PT） containing live Staphylococcus aureus with drug matrix in microbial PT program of drug testing， and to evaluate the laboratory capability of microbiology tests in China. Methods Two kinds of PT samples containing living bacteria with drug matrix were prepared and evaluated. The results of laboratories participated in PT program and their response to the survey questionnaire were collected and analyzed. Results The homogeneity and stability of the PT samples complied with the requirements of CNAS-CL03： 2010. Samples could be stored stably for at least 6 months at -20 ℃. Among 63 laboratories participating in PT program， 53 laboratories （84.1%） achieved satisfactory results. The satisfaction rate was 94.1% （16/17） in 17 government laboratories （27.0% of total 63 laboratories）， 81.4% （35/43） in 43 pharmaceutical quality control laboratories （68.3% of total 63 laboratories）， and 66.7% （2/3） in 3 non-government laboratories （4.8% of total 63 laboratories）， respectively. Conclusion The government laboratories performed better than pharmaceutical quality control laboratories in microbiology tests of drug， and the testing abilities of some pharmaceutical laboratories needs to be improved. The preparation and application of microbial samples in drug matrix could provide evaluation tools for drug testing laboratories in microbiology.

Sample preparation and analysis of proficiency test containing Staphylococcus aureus with drug matrix / 上海预防医学

Objective To prepare samples of proficiency testing （PT） containing live Staphylococcus aureus with drug matrix in microbial PT program of drug testing， and to evaluate the laboratory capability of microbiology tests in China. Methods Two kinds of PT samples containing living bacteria with drug matrix were prepared and evaluated. The results of laboratories participated in PT program and their response to the survey questionnaire were collected and analyzed. Results The homogeneity and stability of the PT samples complied with the requirements of CNAS-CL03： 2010. Samples could be stored stably for at least 6 months at -20 ℃. Among 63 laboratories participating in PT program， 53 laboratories （84.1%） achieved satisfactory results. The satisfaction rate was 94.1% （16/17） in 17 government laboratories （27.0% of total 63 laboratories）， 81.4% （35/43） in 43 pharmaceutical quality control laboratories （68.3% of total 63 laboratories）， and 66.7% （2/3） in 3 non-government laboratories （4.8% of total 63 laboratories）， respectively. Conclusion The government laboratories performed better than pharmaceutical quality control laboratories in microbiology tests of drug， and the testing abilities of some pharmaceutical laboratories needs to be improved. The preparation and application of microbial samples in drug matrix could provide evaluation tools for drug testing laboratories in microbiology.

Elaboration of reference material for cadmium and arsenic in hydrobiological products, for the purpose of being used in a laboratory intercomparation program / Elaboración de un material de referencia para cadmio y arsénico en productos hidrobiológicos, para propósito de ser utilizado en un programa de intercomparación de laboratorios

Reference materials (RM) are tools used in the comparability and traceability of measurements. They are widely used by laboratories for method validation and quality control of assay. Chile must evaluate theperformance of laboratories that analyzing metals in fishery products, despite RM have high prices and are scarce. For that reason, a RM in a hydrobiological product was developed. Reference values for arsenic and cadmium elements for a fishmeal were assigned. The measurement methods for characterization of the material were Inductively Coupled Plasma Mass Spectrometry, Atomic Absorption Spectrometry and Neutron Activation Analysis. Reference values with their expanded uncertainty (U) were established for arsenic 2.64 ± 0.42 mg/kg (U; k = 2) and for cadmium 0.86 ± 0.16 mg/kg (U; k = 2). Homogeneity and stability of the RM allowed its use in a proficiency test for eleven food control laboratories. Results for median were 2.114 mg/kg for arsenic, and 0.863 mg/kg for cadmium. The performance values of the participants were evaluated with a z score obtaining 60% satisfaction for arsenic and 73% for cadmium.The material demonstrated to be suitable for use in interlaboratory proficiency assay. (AU)

Materiales de referencia (MR) son herramientas utilizadas en la comparabilidad y trazabilidad entre mediciones. Laboratorios los utilizan ampliamente en validación de métodos y control de calidad. Chile debe evaluar el desempeño de los laboratorios que analizan metales en productos pesqueros, a pesar de los altos precios y escasez del MR. Por esa razón, se desarrolló un MR en producto hidrobiológico. Se asignaron valores de referencia para arsénico y cadmio en harina de pescado. Los métodos de medición para la caracterización del material fueron Espectrometría de Masas de Plasma Acoplado Inductivamente, Espectrometría de Absorción Atómica y Análisis de Activación de Neutrones. Se establecieron valores de referencia con su incertidumbre (U) para arsénico 2.64 ± 0.42 mg/kg (U; k = 2) y para cadmio 0.86 ± 0.16 mg/kg (U; k = 2). La homogeneidad y estabilidad del MR permitieron su uso en una prueba de aptitud para once laboratorios de control de alimentos. Las medianas fueron 2,114 mg/kg para arsénico y 0,863 mg/kg para cadmio. Se evaluaron los rendimientos de los participantes con un estadístico de puntaje z satisfactorio del 60% para el arsénico y 73% para el cadmio. El material demostró ser adecuado para uso en ensayo de aptitud de intercomparación. (AU)

Analysis of proficiency test for determination of manganese in drinking water in Shaanxi Province / 公共卫生与预防医学

Objective To understand and improve the laboratory detection capacity of water manganese in testing organizations of Shaanxi Province． Methods The self-made manganese capacity testing samples were used as the reference in this proficiency testing program. The homogeneity of the samples was tested by single factor analysis of variance. The t-test method was used to evaluate the stability of the samples. The results of manganese in water provided by participant laboratories were analyzed by the robust statistical technique Z-score. Results A total of 136 laboratories participated in the proficiency testing program throughout the province. Among them, 129 laboratories (including retest laboratory) or 94.85% of total participating laboratories obtained satisfactory results. Conclusion The water quality monitoring agencies of our province had shown a strong detection capability for the determination of metal elements in drinking water, which ensures to provide safe water supply to the residents in Shaanxi Province.

Report of the Korean Association of External Quality Assessment Service on Clinical Mycobacteriology (2017–2018)

Rapid and correct diagnosis is essential for national tuberculosis (TB) control. A greater national concern for quality control (QC) of Mycobacterium tuberculosis (MTB) testing is required to improve the proficiency of domestic clinical laboratories using diverse testing protocols in private and public sectors. External quality assessment (EQA) is an important program accompanying internal QC in clinical TB laboratories. In Korea, the EQA program initiated in 2005 by the Korean Association of External Quality Assessment Service (KEQAS) has made remarkable progress in the harmonization of private and public sectors with governmental support since 2011. An integrative TB EQA program led by the KEQAS with financial support from the Korea Centers for Disease Control and Prevention provides optimized EQA materials for both public and private sectors. In 2017, the KEQAS implemented ‘The Next-Generation Proficiency Testing Program’ equipped with a centralized control system of QC material production and electronic data management, which increased the scale of operating programs from 46 to 54 and recruited 1,700 participants. The TB program was also expanded to provide three times EQA for private laboratories from 2 times a year. For TB EQA programs implemented via the Clinical Microbiology Subcommittee of the KEQAS, survey materials were distributed by sectional orders for tests such as acid-fast bacilli (AFB) smears, AFB culturing and identification, antituberculous drug susceptibility screening, AFB molecular diagnosis, and rapid detection of rifampin and isoniazid resistance. All survey materials were produced by sophisticated manufacturing processes and thoroughly analyzed by various commercial kits, targeted DNA sequencing, and whole-genome sequencing in pre- and post-manufacturing phases for advancement in the EQA program.

Development of External Quality Controls for Human Immunodeficiency Virus Antigen/Antibody Tests in Korea

BACKGROUND: Quality control is important for accurate diagnosis of human immunodeficiency virus (HIV) infection, and proficiency testing with external quality controls is an important part of quality control. This study intended to develop and supply customized external quality controls for HIV antigen/antibody testing fitted with currently used reagents for standardization of HIV infection diagnosis and evaluation of HIV testing competency of laboratories in Korea. METHODS: Serological tests and inactivation were performed on the obtained HIV antibody positive plasma. To manufacture quality controls having the required antibody titers, dilution ratio was searched using VIDAS (bioMérieux, France), Architect (Abbott Laboratories, USA), and Cobas 8000 (Roche Diagnostics, Germany) analyzers. Diluted source plasma was divided into aliquots after filtering. Homogeneity and stability of the produced external quality controls were evaluated. RESULTS: The collected HIV antibody positive plasma was confirmed by Western blot. Dilution ratios for source plasma were produced for each analyzer showing signal-to-cut-off 2–3, 5–7, and 15–16 reactivity. Diluted plasma was made to 1 mL aliquots and total set of 1,500 external quality controls for HIV antigen/antibody were manufactured. Produced controls satisfied the required criteria of homogeneity and showed less than 10% coefficient of variation for stability except negative controls. CONCLUSIONS: Customized external quality controls were developed and qualified for HIV testing reagents used in Korea. Continuous external quality control assessment for HIV tests with controls would be required.

Comparison of commercial HIV-1 viral load tests by using proficiency test results in China,2013-2015 / 中华流行病学杂志

Objective To compare the bio-equivalence among commercial HIV-1 viral load tests,including EasyQ HIV-1 v2.0 (EasyQ) from bioMerieux NucliSens of France;VERSANT HIV-1 RNA 3.0 assay (bDNA) from Siemens Healthcare Diagnostics of USA;COBAS AmpliPrep/COBAS TaqMan HIV-1 test (Taqman) from Roche Molecular Diagnosis of USA;Abbott Real Time HIV-1 Kit (M2000) from Abbott Molecular of USA and two domestic HIV-1 viral load test kits (domestic kit) from DaAn Gene Company of Sun Yat-Sen University and Liaoning Bio-Pharmaceutical company of Northeast pharmaceutical group,by using proficiency test results in China from 2013 to 2015.Methods A total of 2 954 proficiency test results,obtained from 22 positive samples of 6 proficiency tests in 155 laboratories conducted by China CDC were analyzed during 2013-2015.The results from each sample were first logarithmic transformed and then grouped according to the method used,the mean value of logarithmic results was calculated.Subsequently,22 clusters of mean values were analyzed by Bland-Altman analysis for the consistency,and linear regression analysis for the interdependency.Results The results indicated that,by taking Taqman as the reference,EasyQ,M2000,bDNA and domestic kit had good consistency (90％-100％) and interdependency.Conclusion All the viral load tests were bio-equivalent.Moreover,according to the conversion formula derived from domestic proficiency test results,all the viral load results could be converted,which is critical for epidemiological analysis.

Comparison of commercial HIV-1 viral load tests by using proficiency test results in China,2013-2015 / 中华流行病学杂志

Objective To compare the bio-equivalence among commercial HIV-1 viral load tests,including EasyQ HIV-1 v2.0 (EasyQ) from bioMerieux NucliSens of France;VERSANT HIV-1 RNA 3.0 assay (bDNA) from Siemens Healthcare Diagnostics of USA;COBAS AmpliPrep/COBAS TaqMan HIV-1 test (Taqman) from Roche Molecular Diagnosis of USA;Abbott Real Time HIV-1 Kit (M2000) from Abbott Molecular of USA and two domestic HIV-1 viral load test kits (domestic kit) from DaAn Gene Company of Sun Yat-Sen University and Liaoning Bio-Pharmaceutical company of Northeast pharmaceutical group,by using proficiency test results in China from 2013 to 2015.Methods A total of 2 954 proficiency test results,obtained from 22 positive samples of 6 proficiency tests in 155 laboratories conducted by China CDC were analyzed during 2013-2015.The results from each sample were first logarithmic transformed and then grouped according to the method used,the mean value of logarithmic results was calculated.Subsequently,22 clusters of mean values were analyzed by Bland-Altman analysis for the consistency,and linear regression analysis for the interdependency.Results The results indicated that,by taking Taqman as the reference,EasyQ,M2000,bDNA and domestic kit had good consistency (90％-100％) and interdependency.Conclusion All the viral load tests were bio-equivalent.Moreover,according to the conversion formula derived from domestic proficiency test results,all the viral load results could be converted,which is critical for epidemiological analysis.

Assessment of effect of laboratory external quality assessment program on cytogenetic testing / 重庆医学

Objective To analyze the change of chromosome test level after participating in the inter‐laboratory proficiency test(PT) program of the College of American Pathologists (CAP) .Methods The results for participating in CAP PT during 2011-2014 were analyzed ,the accuracy of the cytogenetic chromosome quality control test in this laboratory was obtained accord‐ing to the CAP evaluation results ,and the effect of CAP external quality assessment item on increasing the chromosome detection level in this laboratory was evaluated by analyzing the chromosome band levels before and after participating in CAP .Results This laboratory participated in CAP PT test for 10 times during 2011-2014 ,a total of 59 cases were analyzed ,the accuracy rate for jud‐ging chromosome karyotype was 100% ,the karyotype description accuracy rate was 95 .1% .The chromosome test results of clinical cases in this laboratory displayed that peripheral blood chromosome abnormal detection rate was 18 .9% and bone marrow chromo‐some abnormal detection rate was 25 .9% ,the abnormal rate of newly diagnosed leukemia was 66 .8% ;the detection failure rates of peripheral blood chromosome and bone marrow chromosome were 0 .5% and 5 .0% respectively ;the detection failure rates of pe‐ripheral blood chromosome and bone marrow chromosome after participating in CAP were decreased ,the chromosome band average level was improved ,showing statistical difference compared with those before participating in CAP (P<0 .01) .Conclusion Partici‐pating in high quality external laboratory assessment item can increase the clinical analytic level of cytogenetic chromosome test .

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.

Survey Analysis of ABO Antibody Titration at Four University Hospitals in Korea / 대한수혈학회지

BACKGROUND: The ABO antibody titration is important, especially in case of ABO-incompatible hemolytic disease of newborn, ABO-incompatible bone marrow or solid organ transplantation. However, no standard method for ABO antibody titration has yet been established. We surveyed four university hospitals about the methods of ABO antibody titration and performed inter-laboratory proficiency tests. METHODS: Detailed methods of ABO antibody titration were surveyed at four university hospitals. ABO antibody titer was measured by their customary methods using serum samples from six healthy volunteers with blood groups A (n=2), B (n=2) and O (n=2). RESULTS: Procedures of ABO antibody titration, reportable ranges, sample diluent, source of reagent RBCs and interpretation of end-point were different among four university hospitals. Inter-institutional maximum differences of IgM and IgG ABO antibody titer were 16-fold and 32-fold, respectively. CONCLUSION: Standardization of ABO antibody titration method is needed to reduce inter-laboratory variability, and a periodical external quality control survey is necessary to improve the accuracy of the titration.

Teste de proficiência para medições de radioatividade na medicina nuclear / Proficiency test for radioactivity measurements in nuclear medicine

OBJETIVO: Avaliar o desempenho dos calibradores de radionuclídeos de 55 serviços de medicina nuclear brasileiros em medição de atividade de radiofármaco contendo 99Tc m. Testes de proficiência foram aplicados em 63 resultados originados do programa de comparação promovido pelo Laboratório Nacional de Metrologia das Radiações Ionizantes do Instituto de Radioproteção e Dosimetria. MATERIAIS E MÉTODOS: O desempenho foi avaliado em relação ao critério de aceitação de ±10 por cento de exatidão exigido pela norma brasileira e também aos critérios estabelecidos pela ISO/IEC Guide 43-1, e classificado como "aceitável" ou "não aceitável". Amostras de 99Tc m usadas nas comparações foram fornecidas por alguns dos participantes e calibradas no Laboratório Nacional de Metrologia das Radiações Ionizantes para determinar o valor de referência da atividade. RESULTADOS: Esta comparação com o 99Tc m mostrou que o desempenho aceitável atendendo à exigência da norma regulatória foi de 82,5 por cento, enquanto pelos critérios estabelecidos pela norma ISO/IEC 43-1 foi de 81,0 por cento. Por outro lado, calibradores de radionuclídeos com detector Geiger-Müller apresentaram desempenho inferior quando comparados com os dotados com câmara de ionização. CONCLU-SÃO: Nesta comparação, a avaliação do desempenho baseada nos critérios da ISO/IEC 43-1, os quais são aplicados a laboratórios analíticos, apesar de serem mais restritivas, foi bastante consistente com o critério de exatidão exigido pela norma nacional.

OBJECTIVE: To assess the performance of radionuclide calibrators in 55 Brazilian nuclear medicine services in the measurement of 99Tc m radiopharmaceutical activity. Proficiency tests were applied to data sets with 63 results originated from the comparison program developed by Laboratório Nacional de Metrologia das Radiações Ionizantes of Instituto de Radioproteção e Dosimetria. MATERIALS AND METHODS: The calibrators' performance was evaluated in compliance with the acceptance criterion of ±10 percent accuracy required by the Brazilian standards and also the criteria established by the ISO/IEC Guide 43-1, and classified as either "acceptable" or "non-acceptable". The samples of 99Tc m utilized in the comparison were supplied by some of the participants and calibrated at Laboratório Nacional de Metrologia das Radiações Ionizantes for determining the activity reference value. RESULTS: The present study utilizing 99Tc m has shown that 82.5 percent of the calibrators were considered as acceptable according to the Brazilian standards, while by the criteria established by ISO/IEC 43-1, 81.0 percent were considered as acceptable. On the other hand, radionuclide calibrators with Geiger-Müller detectors presented unsatisfactory performance when compared with calibrators with ionization chambers. CONCLUSION: The performance evaluation based on the ISO/IEC 43-1 criteria, which are applied to analytical laboratories, in spite of being more restrictive, has demonstrated to be quite consistent with the accuracy criterion established by the Brazilian standard.

Quality Assurance of Genetic Testing

The proper quality control and quality assurance of clinical laboratory require not only ceaseless efforts of all lab-related personnel but also systematic programs supported and monitored by institutions or academic societies nationwide. For an external quality control program, 'The Korean Association of Quality Assurance for Clinical Laboratory' is performing proficiency tests and inter-laboratory comparison programs twice a year. This program includes cytogenetics for prenatal tests, constitutional abnormalities and neoplasia, molecular genetics for viruses, tuberculosis, leukemia, genotyping and diagnosis of muscular dystrophy, and neonatal screening of congenital metabolic diseases. For an internal quality control program, each laboratory is mandatory to make the policies for validation of protocols and reagents, training and credentials of individuals performing analysis, sample identification, safety for laboratory staff, and other compliance issues. In addition to those programs, proper testing of quality control materials, periodic monitoring of failure rates, careful review of laboratory errors, statistical analysis of the results, comparison with clinical information, and other programs for quality improvement are also needed. For those purposes, clinical laboratories must be enrolled in an approved external inspection program. 'Laboratory Accreditation Program' of 'Korean Society of Laboratory Medicine' gives an accreditation to each laboratory on a one-or two-year basis. A laboratory's ability to perform proper genetic testing is inspected for hundreds of checklist items encompassing laboratory management, chemistry, cytogenetics and molecular genetics. The programs above have been enhancing the lab quality and welcomed by most institutions and labs that experienced the inspection.