Nairo Massakazu Sumita

Atualização sobre hemoglobina glicada (HbA1C) para avaliação do controle glicêmico e para o diagnóstico do diabetes: aspectos clínicos e laboratoriais

Universidade Federal de Sao Paulo (UNIFESP) Hospital do Rim e Hipertensao Centro Integrado de Hipertensao e Metabologia Cardiovascular

The need of mycophenolic acid monitoring in long-term renal transplants.

Abstract:  Background:  There is little information regarding the 12‐h mycophenolic acid (MPA) pharmacokinetics (PK), a way to monitor the drug and the need of frequent monitoring, in stable patients.

A utilidade dos indicadores da qualidade no gerenciamento de laboratórios clínicos

The use of quality indicators has been appreciated in laboratory management so as to optimize quality and error quantification in several laboratory processes. Furthermore, it assists in the implementation of preventive and corrective measures and it shows their corresponding efficiency. The objective of the present study is to discuss the evolution of quality, mainly in the laboratory area, focusing on the importance of quality indicators in laboratory management. Some pre-analytical, analytical and post-analytical laboratory indicators are also presented and discussed in this work. Finally, we highlight the Brazilian initiative in the Laboratory Indicator Program developed by the Brazilian Society of Clinical Pathology and Laboratory Medicine (SBPC/ML) in partnership with Control-Lab and the Model of Quality Indicator project, which has been developed by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC).

Tradescantia pallida cv. purpurea Boom in the Characterization of Air Pollution by Accumulation of Trace Elements

Abstract Tradescantia pallida cv. purpurea, a plant species widely employed for ornamentation in Brazil, has been successfully used for monitoring the genotoxicity of various agents by the micronucleus assay. To amplify knowledge about its suitability as a bioindicator species, its capacity for accumulating trace elements from urban air pollution was evaluated. T. pallida was rooted using standardized soil, and the vases were distributed in two highly polluted sites of the urban area of São Paulo, Brazil (Cerqueira César and Congonhas districts), and in one unpolluted control site situated approximately 50 km from downtown São Paulo (in Caucaia do Alto). Approximately six months after exposure to pollutants, adult leaves of this plant were collected monthly for 12 months. The leaves were washed with deionized water, dried, and ground for analyses. Characterization of element levels was carried out by neutron activation analysis. Powdered samples and standards were irradiated at the IEA-R1 nuclear reactor for short and long periods, and concentrations of As, Ba, Br, Ca, Ce, Cl, Cr, Co, Fe, K, La, Mn, Na, Rb, Sb, Sc, Sr, Th, and Zn were determined. Analysis of variance applied to the results indicated that samples from polluted sites present the highest concentrations of Ba, Ce, Cr, Co, Fe, La, Sb, and Sc (p < 0.05). Discriminant analysis revealed that it was possible to distinguish the two polluted areas with a precision of 97.5%, based on the amount of pollutant elements measured in the plants at each site. The results indicated the potential use of T. pallida as an accumulator plant for air pollution biomonitoring.

Proteína C reativa: aplicações clínicas e propostas para utilização racional

C-reactive protein (CRP) is an acute-phase protein whose requests have been growing exponentially in several countries, including Brazil. In this study, the use of CRP in several clinical situations was reviewed by a group of physicians comprised by specialists in internal medicine, medical emergencies, intensive care, screening, and laboratory medicine, aiming to analyze the applicable literature and to propose guidelines for a more rational use of this laboratory test. The result was the creation of flowcharts guiding CRP request, adjusted to four different healthcare environments, namely, intensive care units, emergency room, wards, and outpatient clinics. These flowcharts, as well as a more detailed discussion on several clinical recommendations for the test, are presented in this study.

Importância da hemoglobina glicada no controle do diabetes mellitus e na avaliação de risco das complicações crônicas

O diabetes mellitus (DM) continua sendo objeto de pesquisa, dadas as constantes informacoes que os estudos clinicos e os novos recursos laboratoriais incorporam a pratica medica a cada dia e com maiores rapidez e eficiencia. Niveis glicemicos persistentemente elevados sao danosos ao organismo e o descontrole prolongado resulta em complicacoes, incluindo danos em diversos tecidos, perda da funcao normal e falencia de varios orgaos. Para o acompanhamento do portador de DM, a hemoglobina glicada (A1C) tem se firmado como ferramenta util depois de ter sido validada pelos dois estudos clinicos mais importantes sobre a avaliacao do impacto do rigido controle glicemico sobre a incidencia e a progressao das complicacoes do diabetes: o Diabetes Control and Complications Trial (DCCT, 1993) e o United Kingdom Prospective Diabetes Study (UKPDS, 1998). Essas pesquisas demonstraram que manter o nivel de A1C abaixo de 7% reduz o risco de desenvolvimento das complicacoes dessa doenca. O Grupo Interdisciplinar de Padronizacao da Hemoglobina Glicada - A1C, criado pela associacao de diversas sociedades cientificas e farmaceuticas do Brasil, publicou, em 2004, um documento de posicionamento oficial acerca da importância da A1C para a avaliacao do controle glicemico, abordando os principais aspectos clinicos e laboratoriais, incluindo as condicoes de variacao pre-analitica e analitica. Foram estabelecidas as recomendacoes a respeito das indicacoes do teste e dos valores ideais de controle para adultos, criancas e idosos. Segundo este posicionamento, os testes de A1C devem ser realizados pelo menos duas vezes ao ano por todos os portadores de DM. Quando os resultados nao forem adequados e/ou forem realizadas alteracoes no esquema terapeutico, a dosagem deve ser feita depois de tres meses. A dosagem esta indicada tanto para os portadores de diabetes mellitus tipo 1 (DM1) quanto tipo 2 (DM2), sendo que a meta a ser atingida, representando efetivo controle, em ambas as condicoes e abaixo de 7%, tanto no adulto como no adulto jovem. Para as criancas durante a fase pre-puberal, o nivel aceitavel de A1C e de ate 8% e, na fase puberal, ate 8,5%. Nos pacientes idosos, a A1C de ate 8% e considerada apropriada, uma vez que a tentativa de um controle muito rigido da glicemia nesta faixa etaria, assim como nas fases pre-puberal e puberal, pode induzir a efeitos colaterais indesejados, como, por exemplo, hipoglicemia. Para a paciente gestante nao esta indicado o acompanhamento do controle glicemico pela dosagem de A1C, sendo mais eficiente o controle dos niveis das glicemias de jejum e duas horas apos as refeicoes e a dosagem de frutosamina, que corresponde ao conjunto das proteinas plasmaticas glicosadas. O grande diferencial da A1C em relacao a glicemia de jejum e que os niveis daquela variam mais lentamente, dependendo da meia-vida das hemacias, portanto nao retornam ao normal imediatamente depois da normalizacao da glicose no sangue. O tempo para que a A1C atinja os niveis adequados apos um periodo de hiperglicemia e de aproximadamente dez semanas. Assim, a repeticao do exame de A1C para avaliar a eficacia de um tratamento deve ser realizada somente dois a tres meses depois do inicio ou da modificacao do esquema terapeutico. Doencas que alteram a sobrevida das hemacias, como anemia hemolitica e hemorragia, por reduzirem sua vida media, podem resultar em valores falsamente baixos de Hb A1C, enquanto as anemias por carencia de ferro, de vitamina B12 ou de folato, que aumentam a vida media das hemacias, resultam em valores falsamente elevados. Na dependencia da metodologia utilizada, outras condicoes clinicas podem interferir no resultado de A1C, como hipertrigliceridemia, hiperbilirrubinemia, uremia, alcoolismo cronico, uso prolongado de opiaceos ou de salicilatos. O posicionamento oficial brasileiro recomenda a utilizacao de metodos rastreaveis do Diabetes Control and Complications Trial (DCCT), conforme certificado pelo National Glycohemoglobin Standardization Program (NGSP), e estimula a participacao em programas de ensaios de proficiencia especificos para A1C.

Vitamina D: ações extraósseas e uso racional

Recent years have witnessed a substantial increase in the number of seric determinations of vitamin D, in a worldwide basis. At Hospital das Clínicas of Faculdade de Medicina of Universidade de São Paulo that increase reached 700% over the last four years. Nevertheless there are many controversies on the literature about the role of vitamin D in conditions unrelated to the musculoskeletal system. In this study the metabolism, sources and actions of vitamin D on the body are reviewed. Observational studies, clinical trials, systematic reviews and metanalysis which focused on the relationship between the vitamin and conditions such as cancer, cardiovascular disease, diabetes and falls were searched on the literature, analyzed and discussed. Results are presented as quiz and answer, tables and a figure. The role of vitamin D on the above-mentioned conditions is discussed, and the controversial issues stressed.

C-reactive protein: clinical applications and proposals for a rational use

C-reactive protein (CRP) is an acute-phase protein whose requests have been growing exponentially in several countries, including Brazil. In this study, the use of CRP in several clinical situations was reviewed by a group of physicians comprised by specialists in internal medicine, medical emergencies, intensive care, screening, and laboratory medicine, aiming to analyze the applicable literature and to propose guidelines for a more rational use of this laboratory test. The result was the creation of flowcharts guiding CRP request, adjusted to four different healthcare environments, namely, intensive care units, emergency room, wards, and outpatient clinics. These flowcharts, as well as a more detailed discussion on several clinical recommendations for the test, are presented in this study.

Controle da qualidade na coleta do espécime diagnóstico sanguíneo: iluminando uma fase escura de erros pré-analíticos

BACKGROUND: The preanalytical phase is responsible for more than two thirds of all errors attributed to the clinical laboratory and it has only a few routine procedures for the detection of nonconformity. In this phase, the procedures involving phlebotomy, critical to the obtainment of diagnostic blood specimen, are poorly studied with regard to major sources of errors and procedures related to quality control process. OBJECTIVES: The aim of this work is to propose a tool for finding failures in the preanalytical phase and to establish quality indicators, with emphasis on procedures for the collection of diagnostic blood specimens, in order to monitor potential sources of error in this phase. MATERIALS AND METHODS: We evaluated phlebotomy procedures employed in ten clinical laboratories in Sao Paulo city, Brazil. All of them with established quality program. The errors that had a frequency higher than 80% were selected to be part of a checklist aiming to evaluate the performance of phlebotomists. Standards and recommendations established by national and international institutions, such as ANVISA, SBPC/ML and CLSI, served as reference to elaborate the checklist. RESULTS: The proposed checklist covers five points of phlebotomy procedures: tourniquet application time, number of phlebotomists that ask patients to clench forearm muscle prior to collection, friction of the forearm muscle in antisepsis process, correct or incorrect sequence of blood collecting tubes and evaluation of accurate or inaccurate homogenization of collected blood specimens. CONCLUSIONS: Phlebotomy evaluation is an essential part of the quality planning in clinical laboratories. The proposed checklist allows error detection in the preanalytical phase, establishment of quality indicators and implementation of corrective and preventive actions with cost effectiveness and improvement in process efficiency.Introducao: A fase pre-analitica e a responsavel por mais de dois tercos de todos os erros atribuidos ao laboratorio e contempla poucos procedimentos rotineiros para a deteccao de nao conformidades. Nesta fase, os procedimentos envolvendo a flebotomia, criticos para a obtencao do especime diagnostico, sao pouco estudados no que diz respeito as principais fontes de erro, bem como aos procedimentos relacionados com o processo de controle da qualidade. Objetivos: Propor uma ferramenta para averiguacao de falhas na fase pre-analitica e estabelecer indicadores da qualidade, com enfase nos procedimentos de coleta do especime diagnostico sanguineo, visando monitorar potenciais fontes de erro nesta etapa. Materiais e metodos: Foram observados os procedimentos de flebotomia empregados em 10 laboratorios clinicos da cidade de Sao Paulo, todos com programa de qualidade estabelecido. Os erros que apresentaram frequencia superior a 80% foram selecionados para elaboracao de uma lista de verificacao, com a finalidade de avaliar o desempenho de flebotomistas. Normas e recomendacoes estabelecidas por instituicoes nacionais e internacionais, como Agencia Nacional de Vigilância Sanitaria (ANVISA), Sociedade Brasileira de Patologia Clinica/Medicina Laboratorial (SBPC/ML) e Clinical and Laboratory Standards Institute (CLSI), serviram de referencia para a elaboracao da lista de verificacao. Resultados: A lista de verificacao proposta aborda cinco pontos do processo de flebotomia: tempo de aplicacao do torniquete, numero de flebotomistas que solicitam ao paciente execucao da constricao do musculo do antebraco previamente a coleta, friccao do musculo do antebraco no processo de antissepsia, sequencia correta ou nao de utilizacao dos tubos de coleta e avaliacao da homogeneizacao adequada ou nao do especime diagnostico coletado. Conclusao: A avaliacao do processo de flebotomia e parte essencial no planejamento da qualidade no laboratorio. A lista de verificacao proposta permite detectar erros na fase pre-analitica, estabelecer indicadores da qualidade e auxilia no estabelecimento de planos de acoes corretivas e preventivas com reducao nos custos e ganho na eficiencia do processo. resumo unitermos Gestao da qualidade Controle da qualidade Indicadores da qualidade em assistencia a saude

Bioequivalence of a new cyclosporine a formulation to Neoral.

New cyclosporine A (CsA) formulations must prove their bioequivalence to Neoral®, the reference CsA formulation, to allow free prescription for the patients. The aim of this study was to compare the pharmacokinetics (PK) of a new CsA formulation (Zinograf-ME), produced by Strides-Arcolab, to Neoral and to demonstrate their interchangeability in stable renal transplant recipients. Twelve-hour PK studies were obtained from 18 (13 M/5 F) adult patients (mean age 44.7 ± 12 years). They received their renal allografts from 13 cadaver and 5 living donors. Before enrollment, all patients were receiving a third generic CsA for a mean of 48 months. Nine patients were also under azathioprine and 9 under mycophenolate mofetil; 17 received prednisone. A single oral dose of either Zinograf or Neoral was administered. The first PK study was performed with one formulation, and 1 week later, a second PK was done with the other formulation. During the washout period, patients continued taking the third CsA formulation. The drug substitution was done milligram-for-milligram. The CsA whole-blood level was measured by TDx immunoassay. Mean ± SD of area under the curve (AUC), maximum concentration (C max), and concentration at the second hour (C2) of Zinograf were not statistically different from those with Neoral (4019 ± 1466 vs 3971 ± 1325 ng·h/mL, 998 ± 376 vs 1021 ± 356 ng/mL, and 707 ± 254 vs 734 ± 229 ng/mL, respectively). In the same way, the Zinograf 90% confidence interval for either C max (−123, +77 ng/mL) or AUC (−214, +311 ng·mL/h) were within the Neoral bioequivalence interval for the same parameters (±204 ng/mL and ±794 ng·mL/h, respectively). These data demonstrate that the ZinografME CsA formulation is bioequivalent to Neoral.