Interferencia generada por la lipemia en la medición de constituyentes bioquímicos

Introducción. La turbidez por lipemia en las muestras para diagnóstico es una de las principales causas de la aparición de sesgos clínicamente significativos en la medición de magnitudes bioquímicas. Objetivo. Valorar la interferencia por lipemia en la medición de 25 constituyentes bioquímicos en dos analizadores con tecnología de química seca (Vitros 7600®) y química liquida (Atellica® Solution). Métodos. Estudio pre-experimental con pre y posprueba. Se añadieron cantidades crecientes de una emulsión lipídica de nutrición parenteral a siete alícuotas de una mezcla de sueros y se determinó por duplicado la influencia del interferente en 25 constituyentes. Se calculó el porcentaje relativo de desviación de la concentración del constituyente por influencia de la turbidez con respecto a una muestra sin interferente. Se establecieron límites de tolerancia para la interferencia utilizando tres criterios: del distribuidor de reactivos, del error sistemático deseable y del error máximo admisible. Resultados. Los constituyentes que presentaron los mayores sesgos para el analizador de química liquida fueron: fósforo (-84,72%), ALT (+81,25%) y AST (-75,76%), mientras que para la plataforma de química seca los constituyentes: ALT (-79,41%), CK (-28,92%) y lipasa (+24,85%). Se detectó interferencia significativa en diferente número de los constituyentes de acuerdo con el criterio de límite tolerable utilizado. Conclusiones. Los distintos resultados encontrados según la metodología y el analizador utilizado, además de la falta de replicabilidad de los ensayos para la valoración de interferencia por lipemia, origina la necesidad de armonizar los procesos e instaurar límites idénticos de interferencia tolerables entre los laboratorios y proveedores de insumos.

Introduction. Turbidity due to lipemia in diagnostic samples is one of the main causes of the appearance of clinically significant biases in the measurement of biochemical magnitudes. Objective. To assess the interference by lipemia in the measurement of 25 biochemical constituents in two analyzers with dry chemistry technology (Vitros 7600®) and liquid chemistry (Atellica® Solution). Methods. Pre-experimental study with pre and post test. Increasing amounts of a parenteral nutrition lipid emulsion were added to seven aliquots of pooled sera and the influence of the interferent on 25 constituents was determined in duplicate. The relative percentage deviation of the concentration of the constituent due to the influence of turbidity with respect to a sample without interference, was calculated. Tolerance limits for interference were established using three criteria: reagent distributor, desirable systematic error, and maximum permissible error. Results. The constituents that presented the greatest biases for the liquid chemistry analyzer were: Phosphorus (-84.72%), ALT (+81.25%) and AST (-75.76%), while for the dry chemistry platform the constituents, ALT (-79.41%), CK (-28.92%) and lipase (+24.85%). Significant interference was detected in a different number of constituents according to the tolerable limit criteria used. Conclusions. The different results found according to the methodology and the analyzer used, in addition to the lack of replicability of the tests for the evaluation of interference by lipemia, originates the need to harmonize the processes and establish identical limits of tolerable interference between the laboratories and suppliers of inputs.

Evaluación del desempeño analítico de parámetros de verificación de química seca a una gran altitud / Evaluation of analytical performance of dry chemistry verification parameters at high altitude

La instalación correcta de un analizador bioquímico depende del cumplimiento de las especificaciones del fabricante. El fabricante del analizador bioquímico Vitros 4600 (OrthoClinicalDiagnostics), que cuantifica analitos en base al método de química seca, garantiza un buen desempeño analítico de este hasta los 2438 msnm. Si la instalación se realiza a mayores altitudes, el laboratorio clínico debe aplicar protocolos experimentales que demuestren que el desempeño del analizador, tiene validez clínica. Objetivo: Evaluar el desempeño analítico de la química seca en un laboratorio clínico ubicado a gran altitud (Huancayo-Perú, 3259 msnm). Metodología: Estudio aplicativo y longitudinal. Se aplicó el protocolo EP15-A2 de CLSI como referencia de procedimientos estandarizados para calcular el SD y CV (error aleatorio) así como el sesgo (error sistemático) para dos niveles de concentración de algunos analitos de rutina tales como glucosa, úrea, creatinina, triglicéridos y AST, utilizando controles de tercera opinión de Bio Rad. A partir de los datos obtenidos se calculó la métrica sigma como indicador de desempeño analítico para cada analito, utilizando criterios de error total aceptable de CLIA. Resultados: Se obtuvieron métricas sigma, superiores a 4 para todos los analitos, encontrando desempeños: bueno para úrea, muy bueno para glucosa y excelente para creatinina, AST y triglicéridos. Conclusión: Se demostró que la química seca tiene un desempeño analítico aceptable, a pesar de ser utilizada en una altitud superior a las especificaciones del fabricante

Correct installation of a biochemical analyzer depends on compliance with the manufacturer's specifications. The manufacturer of the Vitros 4600 biochemical analyzer (OrthoClinicalDiagnostics), which quantifies analytes based on the dry chemistry method, guarantees its good analytical performance up to 2438 masl. If the installation is carried out at higher altitudes, the clinical laboratory must apply experimental protocols that demonstrate that the performance of the analyzer has clinical validity. Objective: To evaluate the analytical performance of dry chemistry in a clinical laboratory located at high altitude (Huancayo-Peru, 3259 masl). Methodology: Application and longitudinal study. The CLSI protocol EP15-A2 was applied as a reference of standardized procedures to calculate the SD and CV (random error) as well as the bias (systematic error) for two concentration levels of some routine analytes such as glucose, urea, creatinine, triglycerides and AST, using Bio Rad third part controls. From the data obtained, the sigma metric was calculated as an indicator of analytical performance for each analyte, using CLIA criteria of total acceptable error. Results: Sigma metrics were obtained, higher than 4 for all the analytes, finding performances: good for urea, very good for glucose and excellent for creatinine, AST and triglycerides. Conclusion: Dry chemistry was shown to have acceptable analytical performance, despite being used at an altitude higher than the manufacturer's specifications.

Validação de intervalos de referência de exames bioquímicos do laboratório de análises clínicas de um hospital universitário / Validation of reference intervals for biochemical tests at the clinical analysis laboratory of a university hospital

Introdução: Os intervalos de referência (IRs) disponibilizados em laudos de exames laboratoriais orientam a interpretação dos resultados, respaldando a avaliação clínica realizada por profissionais de saúde. Objetivo: Validar IRs de parâmetros bioquímicos, com base nas características da população local, bem como em informações disponíveis nas bulas dos reagentes e na literatura científica. Material e Métodos: Foi realizado um estudo observacional, descritivo e transversal para padronização de IRs de trinta e quatro parâmetros bioquímicos, executados pelo laboratório de análises clínicas de um hospital universitário. Participaram do estudo quarenta indivíduos adultos, pareados pelo sexo, que responderam um questionário sobre o estado geral de saúde. Uma amostra de sangue foi coletada de cada participante e analisada conforme os padrões do laboratório. Resultados: Os dados obtidos com os voluntários saudáveis permitiram a validação dos IRs de albumina, alanina aminotransferase, amilase, aspartato aminotransferase, bilirrubina direta, bilirrubina indireta, bilirrubina total, cálcio iônico, capacidade total e latente de fixação de ferro, creatinoquinase fração MB, cloro, ferro, fosfatase alcalina, fósforo, gama glutamiltransferase, glicose, lipoproteína de alta densidade, lactato, lactato desidrogenase, lipase, magnésio, potássio, proteínas totais, saturação da transferrina, sódio, triglicerídeos e ureia, de ambos os sexos. Ácido úrico foi validado apenas para o sexo masculino e creatinoquinase total (CK) foi validado apenas para o sexo feminino. Conclusão: Os IRs contidos nas bulas destes reagentes representam a população atendida pelo laboratório e podem continuar sendo utilizados. Em contrapartida, os IRs dos analitos colesterol total, lipoproteína de baixa densidade, cálcio, ácido úrico feminino e CK masculino não foram validados e necessitam de novos estudos para a validação dos intervalos de referência utilizados

Introduction: The reference intervals (RIs) provided in laboratory test reports orientate the interpretation of results, supporting the clinical evaluation performed by health professionals. Objective: Validate RIs of biochemical parameters, based on the characteristics of the local population, as well as on information available in the package inserts of the reagents and in the scientific literature. Material and Methods: An observational, descriptive, and cross-sectional study was carried out for the standardization of RIs of thirty-four biochemical parameters, performed by the Clinical Analysis laboratory of a university hospital. Forty adult individuals, matched by sex, participated in the study, who answered a questionnaire about their general health status. A blood sample was taken from each participant and analyzed according to laboratory standards. Results: Data obtained from healthy volunteers allowed the validation of the RIs of albumin, alanine aminotransferase, amylase, aspartate aminotransferase, direct bilirubin, indirect bilirubin, total bilirubin, ionic calcium, total and latent iron-binding capacity, creatine kinase MB fraction, chlorine, iron, alkaline phosphatase, phosphorus, gamma glutamyltransferase, glucose, high density lipoprotein, lactate, lactate dehydrogenase, lipase, magnesium, potassium, total proteins, transferrin saturation, sodium, triglycerides and urea, of both sexes. Uric acid has been validated for males only and total creatine kinase (CK) has been validated for females only. Conclusion: The RIs contained in the package inserts of these reagents represent the population assisted by laboratory and can continue to be used. The RIs of total cholesterol, low-density lipoprotein, calcium, female uric acid and male CK analytes were not validated and require further studies to validate the reference intervals used

The application of sigma metrics in the laboratory to assess quality control processes in South Africa

Objective: This study aimed to determine the sigma metrics of analytes when using different total allowable error guidelines.Methods: A retrospective analysis was performed on 19 general chemistry analytes at Charlotte Maxeke Johannesburg Academic Hospital in South Africa between January 2017 and December 2017. Sigma metrics were calculated on two identical analysers, using internal quality control data and total allowable error guidelines from the Ricos biological variation database and three alternative sources (the Royal College of Pathologists of Australasia, the Clinical Laboratory Improvements Amendment, and the European Federation of Clinical Chemistry and Laboratory Medicine). Results: The sigma performance was similar on both analysers but varied based on the guideline used, with the Clinical Laboratory Improvements Amendment guidelines resulting in the best sigma metrics (53% of analytes on one analyser and 46% on the other had acceptable sigma metrics) and the Royal College of Pathologists of Australia guidelines being the most stringent (21% and 23%). Sodium and chloride performed poorly across all guidelines (sigma < 3). There were also month-to-month variations that may result in acceptable sigma despite poor performance during certain months.Conclusion: The sigma varies greatly depending on the total allowable error, but could be a valuable tool to save time and decrease costs in high-volume laboratories. Sigma metrics calculations need to be standardised

Analysis of Class II Common Problems in the Registration of / 中国医疗器械杂志

From the perspective of technical review, this paper made statistics on the supplement contents of

Clinical Application of Overlapping Confidence Intervals for Monitoring Changes in Serial Clinical Chemistry Test Results

BACKGROUND: Interpretation of changes in serial laboratory results is necessary for both clinicians and laboratories; however, setting decision limits is not easy. Although the reference change value (RCV) has been widely used for auto-verification, it has limitations in clinical settings. We introduce the concept of overlapping confidence intervals (CIs) to determine whether the changes are statistically significant in clinical chemistry laboratory test results.METHODS: In total, 1,202,096 paired results for 33 analytes routinely tested in our clinical chemistry laboratory were analyzed. The distributions of delta% absolute values and cut-off values for certain percentiles were calculated. The CIs for each analyte were set based on biological variation, and data were analyzed at various confidence levels. Additionally, we analyzed the data using RCVs and compared their clinical utility.RESULTS: Most analytes had low indexes of individuality with large inter-individual variability. The 97.5th percentile cut-offs for each analyte were much larger than conventional RCVs. The percentages of results exceeding RCV(95%) and RCV(99%) corresponded to those with no overlap at the 83.4% and 93.2% confidence levels, respectively.CONCLUSIONS: The use of overlapping CIs in serial clinical chemistry test results can overcome the limitations of existing RCVs and replace them, especially for analytes with large intra-individual variation.

EQA-based evaluation of metrological traceability of clinical chemistry test results in Argentina / EQA-based evaluation of metrological traceability of clinical chemistry test results in Argentina

Equivalence of results among laboratories is a major mission for medical laboratories. In the Netherlands, medical laboratories only use homogenous, commercial for general chemistry analytes, whereas in Argentina heterogenous, home brew test applications are common. The effect of this practice difference on test accuracy is studied using key features of the accuracy-based EQA program of the Netherlands. Six frozen, human-based, commutable poolsera, covering the (patho) physiological measuring range for 17 general chemistry analytes, were assayed by ~75 Argentinian labs and ~200 Dutch laboratories in 2014. After removal of outliers, harmonization status among laboratories was evaluated by calculating overall mean interlaboratory coefficients of variation (CVs, %) per analyte and per country for all 6 levels. Evenso, standardization status was evaluated after removal of outliers by calculating overall mean recoveries (%) as compared to the assigned target values per analyte per country for all 6 levels. Absolute median biases were compared to (minimal/desirable) biases derived from biological variation criteria. For serum enzymes interlaboratory CVs in the Argentinian laboratories ranged between 10 and 22%, as compared to 3-6% in the Netherlands. For serum uric acid, creatinine, glucose and total protein, interlaboratory CVs varied between 4.3 and 13.1% in Argentinian labs, as compared to <3.5% in the Netherlands. For serum electrolytes, interlaboratory CVs ranged between 1.8 and 3.8% for Na+; 2.9-5.8% for Cl-; 3.8-7.5% for K+; 9.4-10.4% for Ca2+ and 16.2-22.3% for Mg2+ as compared to ≤2% (Na+, K+, Cl-, Ca2+) and ≤3% (Mg2+) in the Netherlands. Mean recoveries in Argentinian laboratories for e.g. serum creatinine, glucose, CK, Ca2+ and Na+ were 95-119%; 95-104%; 98-102%; 98-102% and 96-100% respectively, whereas min-max recovery ranges were 65-155%; 58-126%; 47-132%; 66-132% and 85-115%. In the Netherlands, absolute mean recoveries were overall 98.9% with a SD of 2.0%. Median biases in Argentinian laboratories ranged from -2.9 to 18.2%; -3.1 - 2.6%; -3.3 - 0.5%; -1.1 - 3.8% and -4.3-0% for serum creatinine, glucose, CK, Ca2+ and Na+. In the Netherlands overall mean/median biases were 1.1% (SD=2.0%). Exchange of commutable, value- assigned EQA-materials was helpful for studying the harmonization and standardization status of medical tests in Argentina, and for revealing the future harmonization and standardization potential. The results clearly demonstrate that metrological traceability of test results in Argentina is on average in line with what is expected; yet, the spreading among laboratories is far too high and should be improved.

La equivalencia de resultados entre laboratorios es una mision importante para los laboratorios medicos. En los Paises Bajos, los laboratorios medicos solo usan aplicaciones comerciales homogeneas, regulatoriamente aprobadas (CE-IVD) para analitos quimicos, mientras que en la Argentina son comunes las aplicaciones heterogeneas caseras. El efecto de esta diferencia practica en la precision de la prueba se estudia utilizando caracteristicas clave del programa EQA, basado en la precision, de los Paises Bajos. Se ensayaron seis pools de sueros, congelados, de origen humano, conmutables, que cubrian el rango de medidas (pato)fisiologicas para 17 analitos de quimica clinica. Estos analitos de quimica clinica fueron analizados por ~75 laboratorios argentinos y ~200 laboratorios holandeses en 2014. Despues de eliminar los valores atipicos, el estado de armonizacion entre los laboratorios fue evaluado calculando los coeficientes de variacion interlaboratorios medios globales (CV%) por analito y por pais para los 6 niveles. No obstante, el estado de estandarizacion se evaluo despues de la eliminacion de valores atipicos mediante el calculo de recuperaciones medias generales (%) en comparacion con los valores asignados por analito por pais para los 6 niveles. Los sesgos medios absolutos se compararon con los sesgos (minimos / deseables) derivados de los criterios de variacion biologica. Para enzimas sericas los CV interlaboratorio en los laboratorios argentinos oscilaron entre 10 y 22%, en comparacion con 3-6% en los Paises Bajos. Para el acido urico serico, creatinina, glucosa y proteinas totales, los CV entre laboratorios variaron entre 4,3 y 13,1% en los laboratorios argentinos, en comparacion con <3,5% en los Paises Bajos. Para los electrolitos sericos, los CV interlaboratorios oscilaron entre 1,8 y 3,8% para Na+; 2,9-5,8% para Cl-; 3,8-7,5% para K+; 9,4-10,4% para Ca2+ y 16,2-22,3% para Mg2+ en comparacion a ≤2% (Na+, K+, Cl-, Ca2+) y ≤3% (Mg2+) en los Paises Bajos. Las recuperaciones medias en laboratorios argentinos para, p.ej. la creatinina serica, glucosa, CK, Ca2+ y Na+ fueron 95-119%; 95-104%; 98-102%; 98-102% y 96-100% respectivamente, mientras que los rangos de recuperacion min-max fueron 65-155%; 58-126%; 47-132%; 66-132% y 85-115%. En los Paises Bajos, las recuperaciones medias absolutas fueron en general del 98,9% con una desviacion estandar (DE) del 2,0%. La mediana de los sesgos medios de los laboratorios argentinos oscilo entre -2,9 y 18,2%; -3,1 - 2,6%; -3,3 - 0,5%; -1,1 - 3,8% y -4,3-0% para creatinina serica, glucosa, CK, Ca2+ y Na+. En los Paises Bajos, las medias / medianas en general fueron de 1,1% (DE=2,0%). El intercambio de los valores asignados a los materiales EQA, conmutables fue de gran ayuda para la armonizacion y estandarizacion de los ensayos medicos en la Argentina y para revelar el potencial futuro de armonizacion y estandarizacion. Estos resultados claramente demuestran que la trazabilidad metrologica de los resultados de las pruebas en la Argentina esta, en promedio, de acuerdo con lo esperable; sin embargo, la dispersion entre laboratorios es muy grande y deberia ser mejorada.

A equivalencia de resultados entre laboratorios e uma missao importante para os laboratorios medicos. Nos Paises Baixos, os laboratorios medicos so utilizam aplicacoes comerciais homogeneas, aprovadas por regulacoes (CE-IVD) para analitos quimicos, ao passo que na Argentina sao comuns as aplicacoes heterogeneas caseiras. O efeito desta diferenca pratica na exatidao do teste e estudado utilizando caracteristicas essenciais do programa EQA, dos Paises Baixos, baseado na exatidao. Foram ensaiados seis pools de soros, congelados, de origem humana, comutaveis, que abrangiam a faixa de medidas (pato)fisiologicas para 17 analitos quimicos gerais. Esses analitos quimicos foram analisados por ~75 laboratorios argentinos e ~200 laboratorios holandeses em 2014. Apos eliminar os valores atipicos, o estado de harmonizacao entre os laboratorios foi avaliado atraves do calculo dos coeficientes de variacao interlaboratorio meios globais (CV%) por analito e por pais para os 6 niveis. Nao obstante, o estado de padronizacao foi avaliado depois da eliminacao de valores atipicos pelo calculo de recuperacoes medias gerais (%) se comparados com os valores atribuidos por analito por pais para os 6 niveis. Os vieses medios absolutos foram comparados com os vieses (minimos / desejaveis) decorrentes dos criterios de variacao biologica. Para enzimas sericas, os CV interlaboratorio nos laboratorios argentinos oscilaram entre 10 e 22%, em comparacao com 3-6% nos Paises Baixos. Para o acido urico serico, creatinina, glicose e proteinas totais, os CV entre laboratorios variaram entre 4,3 e 13,1% nos laboratorios argentinos, em comparacao com <3,5% nos Paises Baixos para os eletrolitos sericos, os CV interlaboratorios oscilaram entre 1,8 e 3,8% para Na+; 2,9-5,8% para Cl-; 3,8-7,5% para K+; 9,4-10,4% para Ca2+ e 16,2-22,3% para Mg2+ em comparacao com ≤2% (Na+, K+, Cl-, Ca2+) e ≤3% (Mg2+) nos Paises Baixos. As recuperacoes medias em laboratorios argentinos para, p.ex. a creatinina serica, glicose, CK, Ca2+ e Na+ foram 95-119%; 95-104%; 98-102%; 98-102% e 96-100% respectivamente, enquanto que os intervalos de recuperacao min-max. foram 65-155%; 58-126%; 47-132%; 66-132% e 85-115%. Nos Paises Baixos, as recuperacoes medias absolutas foram em geral de 98,9% com um desvio padrao (DE) de 2,0%. A mediana dos vieses medios dos laboratorios argentinos oscilou entre -2,9 e 18,2%; -3,1 - 2,6%; -3,3 - 0,5%; -1,1 - 3,8% e -4,3-0% para creatinina serica, glicose, CK, Ca2+ e Na+. Nos Paises Baixos, as medias / medianas em geral foram de 1,1% (DE=2,0%). O intercambio dos valores atribuidos aos materiais EQA, comutaveis, foi de grande ajuda para a harmonizacao e padronizacao dos ensaios medicos na Argentina e para revelar o potencial futuro de harmonizacao e padronizacao. Esses resultados demonstram as claras que a rastreabilidade metrologica dos resultados dos testes na Argentina esta de acordo com o esperavel; a dispersao entre laboratorios ainda e muito grande e deveria ser melhorada.

Pre-analytical errors in clinical chemistry laboratory of a tertiary care hospital

Background: Pre-analytical errors account for up to 70% of all mistakes made in laboratory diagnostics, most of which arise from problems in patient preparation, sample collection, transportation, and preparation for analysis and storage. Pre-analytical errors influence the total error thus hindering TQM in laboratory, consequently decreasing the accuracy and reliability of the results generated. This study was conducted with the aim to determine nature and frequency of the occurrence of pre-analytical errors.Methods: This prospective analytical study was designed to evaluate the pre-analytical errors observed in a total of 13,892 out-patient and inpatient samples. Samples received for routine clinical chemistry analysis were screened for pre-analytical errors. Samples received for other investigations were excluded. We recorded all nonconformities and errors occurring over a 3-month period and corrective measures were suggested to minimise them. Laboratory personnel were asked to register rejections, and pre-analytical causes for rejection of ward as well as out-patient samples collected in the laboratory. Types of inappropriateness were evaluated as follows: hemolyzed, blood collection in wrong tubes, clotted blood, inappropriate timing of collection, improperly labelled samples, insufficient volume of specimen and lipemic samples.Results: A total of 13,892 samples from the outpatient department and in-house patients were received by our clinical biochemistry laboratory during the period from April 2019 to June 2019. Out of these 404 samples were found unsuitable for further processing. This accounted for 2.9% of all samples collected in the laboratory and pre-analytical errors were responsible for these samples to be rejected over a period of 3 months. Rejections arose as a result of the following reasons: 0.92% were rejected due to hemolysis; 0.58% were blood collected in wrong tubes; 0.55% were clotted blood; 0.26% had inappropriate timing of collection; 0.24% were mislabeled samples; 0.20% had insufficient sample quantity and 0.14% were lipemic samples.Conclusions: Of all the samples received in the lab, the overall percentage of rejection is 2.9%. Substantial number of samples undergo repeated testing because of rejection owing to pre-analytical errors. The efforts should be aimed to reduce the rates of rejected samples can provide to improve the quality of laboratory based health care processes.

Clinical biochemistry profile of American Quarter Horse broodmares fed Tifton-85 (Cynodon spp. ) hay and haylage / Perfil bioquímico clínico de matrizes Quarto de Milha alimentadas com feno e haylage Tifton 85 (Cynodon spp. )

The conservation of haylage (a pre-dried feed) can be challenging, since there is an increased risk of mould growth, which can contaminate this foodstuff with mycotoxins. However, when the hygienic quality is secured, haylage enhances grass palatability and provide enough supply of dry matter throughout the year. Due to the lack of information regarding its effect on blood parameters in horses fed exclusively with this foodstuff, the aim of this study is to provide information regarding its use in comparison to hay and ensure that it does not affect horses' biochemical profile. Twelve Quarter Horse broodmares were distributed into two groups, each fed with Tifton-85 (Cynodon spp.) hay or haylage for a period of 28 days, and the biochemical profile was done in five different times (T0 before the experiment started and, chronologically, seven days apart - T1, T2, T3 and T4), It was analyzed total protein (TP) and its fractioning; enzymes alanine aminotransferase, aspartate aminotransferase and γ-glutamyl-transferase; endogenous catabolism products urea and creatinine; and ions calcium and phosphorus. Mycotoxins in haylage were also investigated and remained below the legislation thresholds. Only TP was higher in the last sampling (T4) of the haylage group, which may be related to the foodstuff's higher protein digestibility. No differences were observed between serum enzymes, urea, creatinine and Ca/P from both experimental groups. Haylage has proven to be safe, when well prepared for horses, without causing impairing side effects, as shown by the normal serum biochemistry parameters presented in this study.(AU)

A conservação do haylage (alimento pré-seco) pode ser desafiadora, considerando o aumento do risco de crescimento de fungos, com consequente produção de micotoxinas. Entretanto, quando a qualidade da higiene e armazenamento é assegurada, o haylage aumenta a palatabilidade da forragem e fornece suplemento de matéria seca suficiente ao longo do ano. Devido à falta de informação relativa aos efeitos dessa alimentação nos parâmetros sanguíneos de equinos alimentados exclusivamente com essa dieta, o objetivo do presente estudo é avaliar o perfil bioquímico sanguíneo dos equinos após administração da haylage em comparação com feno. Doze matrizes Quarto de Milha foram distribuídas em dois grupos, cada um recebendo feno ou haylage de Tifton 85 (Cynodon spp.) por um período de 28 dias. O perfil bioquímico foi realizado em cinco tempos (T) diferentes (T0, antes do início do experimento e cronologicamente, a cada sete dias após o fornecimento das dietas - T1, T2, T3 e T4) para análise de proteína total (PT) e seu perfil fracionado, das enzimas alanina aminotransferase, aspartato aminotransferase, γ-glutamil-transferase, dos produtos de catabolismo creatinina e ureia e, dos íons cálcio e fósforo. Micotoxinas no haylage foram investigadas e mantiveram-se abaixo dos limites determinados pela legislação brasileira. O perfil bioquímico revelou, somente, elevação da PT em T4 no grupo que recebeu haylage, o que pode estar relacionado à sua maior digestibilidade proteica. Nenhuma diferença foi observada nos outros parâmetros estudados em ambos os grupos experimentais. Conclui-se que Haylage é comprovadamente seguro, quando bem preparado para equinos, sem causar efeitos na saúde geral, conforme demonstrado pelos exames bioquímicos no presente estudo.(AU)

Patient data used in internal quality control / 中华检验医学杂志

Objective Quality control procedure based on the patient data in clinical chemistry was set up in laboratory information system (LIS). Methods Clinical chemistry tests results of outpatients and inpatients were collected from January 2016 to March 2017 in Zhejiang Provincial People's Hospital. Statistical results of daily patient data, including Xˉ, P2.5, P5, P10, P25, P50, P75, P90, P95 and P97.5 were calculated. Secondly, cumulative coefficients of variation (CV) of these statistical datawere calculated and compared to different criterions. Optimal analytes and related control concentrations were chosen. The minimum number of patient sample which use Xˉ as control point was calculated by PASS 11.0 software. Finally, the quality control procedure was set up base on the LIS and was verified by patient data. Results In outpatients, Xˉwas chosen as control point in AFU, APOA, APOB, CA, CL, HDL, K, MG, NA, NEFA, TP and URIC and the minimum number of sample needed were 23, 23, 30, 8, 10, 24, 34, 8, 8, 20, 13 and 22. P25 was chosen in ALP and TBIL. P50 was chosen in AST, GLU, GPDA and PHOS.P75 was chosen in ALB, CHE, CREA and DBIL. In inpatients, Xˉ was chosen as control point in AFU, ALB, APOA, APOB, CA, CL, HDL, K, Lpa, MG, NA, NEFA, TP and URIC and the minimum number of sample needed were 73, 19, 34, 18, 10, 30, 36, 21, 87, 12, 17, 51, 26 and 52;P25 was chosen in ALP, ALT, AST, CREA, DBIL, LDH, TBIL and TG. P50 in PHOS, P75 in GPDA, and P90 in CHE. 200 samples were needed in the tests which used percentiles as control points. Most CVs of these control points were higher than the commercial quality control used every day. Finally, a quality control procedure based on patient data were set up in LIS. L-J and Z score charts were used to find out systematic bias. Conclusion Patient data used in internal quality control was an economical and practical way, which can make up for the deficiency of traditional method.

Exploration and practice of the combination of pluralistic teaching and process assessment in the clinical biochemical teaching / 中华检验医学杂志

Clinical biochemical examination is an important part of medical laboratory, and it is also the key and difficult point of all kinds of examinations.However,the teaching of clinical biochemistry is easily to enter the misunderstanding of"focusing only on the instrument operation, while others depend on self-study". There is even confusion that teachers don't know what to teach and students don't know what to learn.In this paper, the teaching experience of the clinical biochemical laboratory is described,formulated a scientific block training program, adopted the teaching mode of combining tutorial responsibility with daily teaching,flexibly used a variety of teaching methods and procedural examinations, and greatly improved the teaching quality.

Exploration and practice of the combination of pluralistic teaching and process assessment in the clinical biochemical teaching / 中华检验医学杂志

Clinical biochemical examination is an important part of medical laboratory, and it is also the key and difficult point of all kinds of examinations.However,the teaching of clinical biochemistry is easily to enter the misunderstanding of "focusing only on the instrument operation, while others depend on self-study". There is even confusion that teachers don′t know what to teach and students don′t know what to learn.In this paper, the teaching experience of the clinical biochemical laboratory is described,formulated a scientific block training program, adopted the teaching mode of combining tutorial responsibility with daily teaching,flexibly used a variety of teaching methods and procedural examinations, and greatly improved the teaching quality.

The performance evaluation of unassayed biochemistry serum controls / 中华检验医学杂志

Objective@#To evaluate the inter-bottle variations, stability in consumption and interchangeability of unassayed biochemistry serum controls.@*Methods@#Comparison between unassayed serum controls from a domestic "Pretrol®" and an international "Bio-Rad" manufacturer was conducted in department of laboratory, in May 2016, with Roche Cobas 8000, Roche Hitachi 7600 and Siemens 2400 modular analyzer. The inter-bottle variation was determined by monitoring the inter-batch variation of 10 bottles of control samples after eliminating the intra-batch variation from the same bottle. Stability in consumption was determined as the precision after 7 days storage under 2 ℃ to 8 ℃ or 30 days of storage under -20 ℃ since reconstitution. The interchangeability was determined as the precisionbetween the controls from different manufacturers for the same test.@*Results@#The inter-bottle imprecision of controls from domestic manufacturer for 13 biochemistry tests (CV concentration 1/CV concentration 2) were potassium (0.26%/0.42%), sodium (0.26%/0.21%), phosphorus (0.00%/0.62%), cholesterol (0.56%/0.54%), total protein (0.52%/0.33%), albumin (0.44%/2.00%), alanine aminotransferase (1.72%/0.57%), γ-glutamylaminotransferase (0.52%/0.62%), aspartate aminotransferase (3.10%/1.09%), lactate dehydrogenase (0.76%/0.91%), alkaline phosphatase (1.13%/0.97%), amylase (0.30%/0.39%) and glucose (0.00%/0.40%). The stability in consumption of the controls from the domestic manufacturer (CV concentration 1/CV concentration 2 under 2 ℃ to 8 ℃storage; CV concentration 1/CV concentration 2 under -20 ℃ storage) were potassium (1.06%/0.36%; 0.74%/0.48%), sodium (0.49%/0.59%; 0.72%/0.65%), phosphorus (0.95%/0.80%; 1.43%/0.84%), cholesterol (1.49%/1.58%; 2.17%/1.80%), total protein (0.84%/0.75%; 1.60%/1.68%), albumin (1.33%/2.28%; 1.94%/2.43%), alanine aminotransferase (1.41%/0.51%; 3.24%/1.60%) γ-glutamylaminotransferase (1.16%/1.16%; 2.85%/2.49%), aspartate aminotransferase (4.37%/2.14%; 2.99%/1.31%), lactate dehydrogenase (2.70%/2.54%; 3.84%/2.97%), alkaline phosphatase (2.63%/1.96%; 2.31%/2.10%), amylase (0.95%/2.19%; 1.58%/1.38%) and glucose (0.60%/0.48%; 1.41%/1.55%). The Inter-bottle variation and stability in consumption of biochemistry test unassayed controls from the domestic manufacturer were compatible for clinical assay according to the CV% specification from the Clinical Biochemistry Test Quality Requirement (WS/T 403-2012). The imprecision of the controls from both the domestic and international manufacturers (CVp concentration 1/CVp concentration2; CVq concentration 1/CVq concentration 2) were potassium (0.52%/0.46%; 2.39%/0.47%), sodium (0.30%/0.17%; 0.81%/0.47%), phosphorus (2.72%/1.11%; 4.57%/2.07%), cholesterol (0.29%/1.38%; 2.94%/1.81%), total protein (0.66%/2.46%; 1.85%/2.54%), alkaline phosphatase (2.67%/4.66%; 3.58%/8.55%), total bilirubin (5.71%/5.09%; 9.55%/7.41%), albumin (1.10%/2.61%; 4.79%/1.93%), alanine aminotransferase (6.42%/1.25%; 5.74%/1.63%), γ-glutamylaminotransferase (2.27%/4.35%; 4.38%/0.74%), aspartate aminotransferase (0.56%/2.84%; 0.91%/2.11%) and lactate dehydrogenase (2.36%/2.47%; 3.10%/1.52%). The interchangeability of serum controls from domestic manufacturer was better than clinical serum samples.@*Conclusion@#The unassayed serum biochemistry test controls from domestic manufacturer are suitable for the intra-laboratory quality control and showed a promising compatibility for inter-laboratory quality control usage.

The performance evaluation of unassayed biochemistry serum controls / 中华检验医学杂志

Objective To evaluate the inter-bottle variations, stability in consumption and interchangeability of unassayed biochemistry serum controls. Methods Comparison between unassayed serum controls from a domestic "Pretrol?" and an international "Bio-Rad" manufacturer was conducted in department of laboratory, in May 2016, with Roche Cobas 8000, Roche Hitachi 7600 and Siemens 2400 modular analyzer. The inter-bottle variation was determined by monitoring the inter-batch variation of 10 bottles of control samples after eliminating the intra-batch variation from the same bottle. Stability in consumption was determined as the precision after 7 days storage under 2℃ to 8℃ or 30 days of storage under -20 ℃ since reconstitution. The interchangeability was determined as the precisionbetween the controls from different manufacturers for the same test. Results The inter-bottle imprecision of controls from domestic manufacturer for 13 biochemistry tests (CV concentration 1/CV concentration 2) were potassium (0.26％/0.42％), sodium (0.26％/0.21％), phosphorus (0.00％/0.62％), cholesterol (0.56％/0.54％), total protein (0.52％/0.33％), albumin (0.44％/2.00％), alanine aminotransferase (1.72％/0.57％),γ-glutamylaminotransferase (0.52％/0.62％), aspartate aminotransferase (3.10％/1.09％), lactate dehydrogenase (0.76％/0.91％), alkaline phosphatase (1.13％/0.97％), amylase (0.30％/0.39％) and glucose (0.00％/0.40％). The stability in consumption of the controls from the domestic manufacturer (CV concentration 1/CV concentration 2 under 2℃to 8℃storage;CV concentration 1/CV concentration 2 under-20℃ storage) were potassium (1.06％/0.36％; 0.74％/0.48％), sodium (0.49％/0.59％; 0.72％/0.65％), phosphorus (0.95％/0.80％;1.43％/0.84％), cholesterol (1.49％/1.58％;2.17％/1.80％), total protein (0.84％/0.75％; 1.60％/1.68％), albumin (1.33％/2.28％; 1.94％/2.43％), alanine aminotransferase (1.41％/0.51％;3.24％/1.60％) γ-glutamylaminotransferase (1.16％/1.16％; 2.85％/2.49％), aspartate aminotransferase (4.37％/2.14％; 2.99％/1.31％), lactate dehydrogenase (2.70％/2.54％; 3.84％/2.97％), alkaline phosphatase (2.63％/1.96％; 2.31％/2.10％), amylase (0.95％/2.19％; 1.58％/1.38％) and glucose (0.60％/0.48％; 1.41％/1.55％). The Inter-bottle variation and stability in consumption of biochemistry test unassayed controls from the domestic manufacturer were compatible for clinical assay according to the CV％ specification from the Clinical Biochemistry Test Quality Requirement (WS/T 403-2012). The imprecision of the controls from both the domestic and international manufacturers (CVp concentration 1/CVp concentration2;CVq concentration 1/CVq concentration 2) were potassium (0.52％/0.46％; 2.39％/0.47％), sodium (0.30％/0.17％; 0.81％/0.47％), phosphorus (2.72％/1.11％;4.57％/2.07％), cholesterol (0.29％/1.38％;2.94％/1.81％), total protein (0.66％/2.46％;1.85％/2.54％), alkaline phosphatase (2.67％/4.66％;3.58％/8.55％), total bilirubin (5.71％/5.09％; 9.55％/7.41％), albumin (1.10％/2.61％; 4.79％/1.93％), alanine aminotransferase (6.42％/1.25％;5.74％/1.63％), γ-glutamylaminotransferase (2.27％/4.35％; 4.38％/0.74％), aspartate aminotransferase (0.56％/2.84％; 0.91％/2.11％) and lactate dehydrogenase (2.36％/2.47％; 3.10％/1.52％). The interchangeability of serum controls from domestic manufacturer was better than clinical serum samples. Conclusion The unassayed serum biochemistry test controls from domestic manufacturer are suitable for the intra-laboratory quality control and showed a promising compatibility for inter-laboratory quality control usage .

Annual Report on the External Quality Assessment Scheme for General Chemistry in Korea (2017)

In 2017, the clinical chemistry proficiency testing program consisted of 24 programs with the addition of the urine chemistry program in the Korean Association of External Quality Assessment Service. The routine chemistry program consisted of 32 test items, including osmolality, total CO2, and estimated glomerular filtration rate tests, and the urine chemistry program consisted of 12 test items, including the albumin test. Based on the information and results of each test item entered by each institution, statistical analysis data according to test method, instrument, and reagent were reported. The statistics included the number of participating institutions, mean, standard deviation, coefficient of variation, median, minimum, and maximum values for each group. Each report was composed of a table, histogram, Levy-Jennings chart, and standard deviation index showing statistics by each test item. A total of 14 items, including albumin, were evaluated by more than 1,000 institutions, and the number of participating institutions is continuously increasing. The coefficient of variation tended to increase, as the concentration of the control material was lower for each test item. Most of them showed a coefficient of variation within 10%. Alkaline phosphatase and lactate dehydrogenase were found to have high coefficients of variation due to differences in measurement values between measurement methods. The distribution of measurement methods in general chemistry test items was not significantly different from that of previous years, and the distribution of measurement methods for albumin, glucose, phosphorus, and protein among the urine chemistry program was different from that of the routine chemistry program.

Establishment and application of autoverification procedure for clinical chemistry test results / 中华检验医学杂志

Objective@#To develop autoverification rules to assistant the verification of biochemical results, based on laboratory information management system. @*Methods@#Designed six kinds of autoverification logic rules according to the guidelines of Clinical and Laboratory Standards Institute (CLSI) AUTO-10A and Accreditation Criteria for the Quality and Competence of Medical Laboratories(ISO15189: 2012), based on in-control of the Internal Quality Control. Those rules inculds: logic disorder rules, critical value rules, warning value rules, delta check rules, relevant contradictions rules, abnormal mode rules, etc. Those rules was setted up in laboratory information management system of Dian Diagnostics. From October 2016 to April 2017, The status of autoverification was checked according to the items and bar code, and compared with clinical diagnostic and manual review. @*Results@#The passing rate of autoverification is over 65% when counted according to tests and is 45% when counted according to sample code, the coincidence rate is 92% with clinical diagnosis.In passing results of autoverification, the coincidence rate is 97.48% to 100% when campared with manual verification, and in not-passing results, the coincidence rate is 82.98% to 85.21%. @*Conclusion@#(1)Autoverification can verify half of routine biochemical test results by setting intelligent logics and rules. (2)Autoverification rules must be verified by a certain amount of test results before they can be formally applied. (3)Autoverification could improve the speed and efficiency of post-test steps.(Chin J Lab Med, 2018, 41: 547-553)

Development of measurement technology for glycated hemoglobin / 中华检验医学杂志

Hemoglobin A1c ( HbA1c ) is a glycated hemoglobin characterized by non-enzymatic binding of glucose to the N-terminal valine residue on the β-chain of the hemoglobin A , is widely utilized as a golden biomarker for diabetes mellitus management because it provides valuable information for long -term glycemic control and assessment of patient risk for chronic complications .In 2010 the American Diabetes Association (ADA) suggested a cut-off value of 6.5％ (48 mmol/mol) HbA1c to diagnose diabetes.The rapid development of measurement technology has led to the application of kits based on different principles to detect HbA1c .This review summarizes the common HbA 1c methods including high performance liquid chromatography, immunoassay, enzymatic, and electrophoresis, and briefly introduces the development of measurement technology for HbA1c.

The measurement of hemoglobin A1c and its application in diabetes mellitus diagnosis / 中华检验医学杂志

Although it has been widely used in the diagnosis and management of diabetes abroad , the application of hemoglobin A 1c ( HbA1c ) test is restricted due to the difference of test ability between various level laboratories in China.The methods, interference and standardization of HbA 1c are still worthy of continuous paying attention by laboratory physicians . How to choose the most economical and efficient method, and how to provide accurate and reliable results for patients are the priorities which can promote the application of HbA1c in diabetes diagnosis and management in China.

Quality Management of Clinical Chemistry Tests in Blood Center / 대한수혈학회지

The main goal of transfusion medicine is safe and appropriate blood transfusion in all situations. To accomplish this, it is essential to have a high level quality management system for the entire process from blood donation to transfusion. Regulations regarding blood management have been adopted and strictly managed in Korea since 2007. Blood center's blood management tasks should establish appropriate quality management systems to ensure the safe supply of blood, as well as the basic resources of personnel, facilities and equipment in accordance with laws and regulations governed by the Ministry of Health and Welfare in Korea. The purpose of this review is to examine the contents and processes for quality control of clinical chemistry tests in Korean blood centers.

The Advantage of Cyclosporine A and Methotrexate Rotational Therapy in Long-Term Systemic Treatment for Chronic Plaque Psoriasis in a Real World Practice

BACKGROUND: Psoriasis is a chronic inflammatory disease. In the treatment of psoriasis, cyclosporine is commonly prescribed systemic agents. However, long-term use of cyclosporine is not recommended because of side effects such as nephrotoxicity or hypertension. OBJECTIVE: To ascertain the improved safety of rotational therapy using cyclosporine and methotrexate, we investigated the frequency of abnormal results in laboratory test after long term rotational therapy using cyclosporine and methotrexate. METHODS: From January 2009 to June 2014, patients who were treated with cyclosporine or methotrexate were enrolled. The clinical data and usage of medications were reviewed. Laboratory tests were conducted before starting the treatment and regularly follow-up. The occurrences of any laboratory abnormalities during the treatments were investigated. RESULTS: A total of 21 psoriatic patients were enrolled. The mean of medication period and cumulative dose of cyclosporine and methotrexate were 497.81±512.06 days and 115.68±184.34 g in cyclosporine and 264.19±264.71 days and 448.71±448.63 mg in methotrexate. Laboratory abnormalities were found in total two patients after rotational therapy: two patients (9.5%) in aspartate aminotransferase/alanine aminotransferase and one patient (4.8%) in uric acid. No laboratory abnormalities were found in renal function test. CONCLUSION: We found that the rotational approaches using cyclosporine and methotrexate reduced the possibility of the development of nephrotoxicity. In addition to other advantage such as quick switching from one agent to another, the rotational therapy using cyclosporine and methotrexate can minimize the adverse events during the systemic treatment of chronic plaque psoriasis.