Chagasic cardiomyopathy is marked by a unique signature of activated CD4+ T cells.

Chagas disease is a neglected tropical disease in Latin America and an imported emerging disease worldwide. Chronic Chagas disease cardiomyopathy (CCC) is the most prominent clinical form and can lead to heart failure, thromboembolism, and sudden death. While previous reports have supported a role for CD4+ T lymphocytes in the pathogenesis of CCC a comprehensive analysis of these cells during different clinical forms is lacking. Here, we used high-dimensional flow cytometry to assess the diversity of circulating CD4+ T cells in patients with distinct clinical forms. We found increased frequencies of CD4+CD69+ T cells in patients compared to controls. CD39+ regulatory T cells, represented by mesocluster 6 were reduced in mild CCC patients compared to controls. Cytotoxic CD4+ T cells co-expressing granzyme B and perforin were expanded in patients with Chagas disease and were higher in patients with mild CCC compared to controls. Furthermore, patients with mild CCC displayed higher frequencies of multifunctional effector memory CD4+ T cells. Our results demonstrate an expansion in activated CD4+ T cells and a decrease in a functional subset of regulatory T cells associated with the onset of Chagas cardiomyopathy, suggesting their role in the establishment of cardiac lesions and as potential biomarkers for disease aggravation.

Processos de Desenvolvimento do Raciocínio Clínico em Estudantes de Medicina / Clinical Reasoning Development in Medical Students

RESUMO O raciocínio clínico se refere ao processo cognitivo, através do qual, o médico é capaz de estabelecer o diagnóstico correto e propor uma conduta adequada frente a um problema clínico encontrado. Apesar da grande evolução do conhecimento médico ao longo dos tempos, a prática clínica é ainda hoje, muito dependente da habilidade profissional de elaborar um diagnóstico correto e, a partir deste, definir a melhor conduta. Trabalhos recentes vêm demonstrando que erros diagnósticos constituem fonte de doenças evitáveis e morte, promovendo prejuízos clínicos e financeiros a pacientes, familiares e à nação. As escolas médicas e seus docentes têm o desafio de facilitar a aquisição desta competência pelos estudantes, pois, trata-se de um dos maiores atributos a ser desenvolvido durante o curso médico. Nas últimas três décadas, os processos envolvidos no aprendizado e desenvolvimento do raciocínio clínico vêm sendo estudados e muito já se sabe sobre as fases envolvidas na formação desta importante habilidade. Teorias e estudos cognitivos sobre a formação e o uso da memória podem ser encontrados em diversas áreas do conhecimento. No entanto, pouco material existe com uma discussão direcionada para o ensino médico. Este é um dos objetivos deste artigo, apresentar uma revisão das principais teorias e pesquisas sobre os processos do desenvolvimento do raciocínio clínico, fornecendo aos professores um material que permita a compreensão desta fascinante área do ensino médico. Espera-se assim, contribuir para a formação docente, estimular o desenvolvimento da pesquisa em educação médica e fornecer subsídio técnico para o planejamento de estratégias instrucionais orientadas pelos princípios do aprendizado do raciocínio clínico. Para facilitar a compreensão, as teorias serão apresentadas em tópicos. No entanto, uma vez que o raciocínio clínico é uma atividade cognitiva complexa, é importante lembrar que os mecanismos propostos em cada tópico apresentam fatores que se sobrepõem e muitas vezes ocorrem simultaneamente.

ABSTRACT Clinical reasoning refers to the cognitive process by which the physician is able to provide a correct diagnosis and appropriate treatment for a clinical problem. Despite the great medical knowledge evolution over the time, clinical practice is still very dependent on professional ability to make a correct diagnosis. Studies have shown that diagnostic errors are an important source of preventable diseases and death, promoting clinical and financial damage to patients, families and nation. Medical schools and teachers face the challenge of promoting the development of this competence in medical students as it is one of the greatest attributes to be developed during medical school. In the last three decades, the processes involved in learning and developing clinical reasoning have been studied and now much is known about the stages involved in the formation of this important skill. Theories and cognitive studies on memory building and function can be found in several areas of knowledge, however, little information exists with a discussion focused on medical education. The aim of this work is present a review of the main theories and researches on clinical reasoning, providing teachers with a comprehensive review that allows understanding this fascinating medical education area. It is hoped, to offer a contribution on medical education, providing medical teachers with technical material for planning their instructional strategies guided by clinical reasoning learning principles and stimulate research on medical education. To favor comprehension, the theories will be presented by topics, however, since clinical reasoning is a complex cognitive activity, it is important remember that the information proposed in each topic have factors that overlap and often occur simultaneously.

The effect of self-explanation of pathophysiological mechanisms of diseases on medical students' diagnostic performance.

Self-explanation while diagnosing clinical cases fosters medical students' diagnostic performance. In previous studies on self-explanation, students were free to self-explain any aspect of the case, and mostly clinical knowledge was used. Elaboration on knowledge of pathophysiological mechanisms of diseases has been largely unexplored in studies of strategies for teaching clinical reasoning. The purpose of this two-phase experiment was to investigate the effect of self-explanation of pathophysiology during practice with clinical cases on students' diagnostic performance. In the training phase, 39 4th-year medical students were randomly assigned to solve 6 criterion cases (3 of jaundice; 3 of chest pain), either self-explaining the pathophysiological mechanisms of the findings (n = 20) or without self-explaining (n = 19). One-week later, in the assessment phase, all students solved 6 new cases of the same syndromes. A repeated-measures analysis of variance on the mean diagnostic accuracy scores showed no significant main effects of study phase (p = 0.34) and experimental condition (p = 0.10) and no interaction effect (p = 0.42). A post hoc analysis found a significant interaction (p = 0.022) between study phase and syndrome type. Despite equal familiarity with jaundice and chest pain, the performance of the self-explanation group (but not of the non-self-explanation group) on jaundice cases significantly improved between training and assessment phases (p = 0.035) whereas no differences between phases emerged on chest pain cases. Self-explanation of pathophysiology did not improve students' diagnostic performance for all diseases. Apparently, the positive effect of this form of self-explanation on performance depends on the studied diseases sharing similar pathophysiological mechanisms, such as in the jaundice cases.

Versão brasileira do Attribution Questionnaire – Adaptação transcultural e validação de propriedades psicométricas / Brazilian version of the Attribution Questionnaire – Cross cultural adaptation and validation of psychometric properties

RESUMO Objetivo Realizar a adaptação transcultural do Attribution Questionnaire – AQ27 para o português falado no Brasil a partir da versão de Portugal e validar as propriedades psicométricas da escala por meio da análise fatorial exploratória. Métodos Após a adaptação semântica e cultural, o questionário foi aplicado a 431 alunos do 1º ao 6º ano do Curso de Medicina Unifenas-BH, Brasil, e, em seguida, conduziu-se análise fatorial exploratória pelo método de extração de componentes principais e rotação Varimax. Resultados A versão final brasileira do Questionário de Atribuição (AQ-26B) apresentou um fator a menos que a versão original em inglês e a portuguesa devido à fusão dos fatores Medo e Percepção de Perigo, o que gerou a supressão da questão 11 do questionário brasileiro por não apresentar valores psicométricos adequados. Dificuldades linguísticas relacionadas à interpretação da questão 11 e sua maior complexidade de significado latente parecem ter contribuído com esse resultado. Conclusões O questionário brasileiro (AQ-26B) manteve parâmetros de validade e confiabilidade adequados observando-se coerência com o modelo teórico original. Além disso, mostrou-se de fácil aplicação, demonstrando ser um instrumento útil para avaliar o estigma relacionado à doença mental entre alunos de medicina de escolas médicas brasileiras.

ABSTRACT Objective A cross-cultural adaptation of the Portuguese version of the Attribution Questionnaire – AQ27 for Brazilian speakers and an exploratory factor analysis were conducted in order to validate the scale’s psychometric properties. Methods After semantic and cultural adaptation of the questionnaire, exploratory factor analysis was conducted through principal component extraction and Varimax rotation methods in 431 students, from the first to the last years of the course, at Unifenas Medical Course in Belo Horizonte, Brazil. Results The final Brazilian version of the Attribution Questionnaire (AQ-26B) had 8 factors instead of 9 from the original American and Portuguese versions. This change was due to the merger of Fear and Dangerousness factors. Question 11 was removed from the Brazilian version because it did not present adequate psychometric values. Language difficulties, related to the interpretation of its meaning and its complex latent meaning, seemed to have contributed to this result. Conclusions The Brazilian version of the Attribution Questionnaire (AQ-26B) presented suitable validity and reliability parameters as well as theoretical coherence to the original model. Moreover, it proved easy to apply, showing to be a useful tool to evaluate the stigma attached to mental illness in Brazilian medical students.

Detection of anti-nuclear antibodies by indirect immunofluorescence on HEp-2 cells: setting the appropriate screening dilution for the diagnosis of autoimmune rheumatic diseases.

OBJECTIVE: To establish the abnormal title and the appropriate screening dilution for ANA (antinuclear antibodies) test by indirect immunofluorescence on HEp-2 cells (ANA HEp-2). METHODS: An analysis of ANA Hep-2 in serum samples from 126 healthy individuals was performed. The samples were screened at a dilution of 1:80, and those positive were diluted to the title of 1:5120. The abnormal title of ANA was defined as that corresponding to the 95th percentile of the test in this population. The sensitivity of the different titles of antinuclear antibodies was determined in a group of 136 patients with a diagnosis of autoimmune rheumatic disease, and the specificity was determined in a group of 118 patients with other rheumatic diseases. The optimal cutoff value of the test was determined by ROC curve analysis. RESULTS: The frequency of ANA positivity in healthy subjects was 13.2%. There was no difference in the frequency of positive results according to gender or age. The abnormal title of ANA was defined as the dilution of 1:160. The 1:80 dilution had sensitivity of 87.7% and specificity of 67.8%, while the 1:160 dilution had sensitivity of 82% and specificity of 73.7%. By ROC curve analysis, a dilution of 1:160 corresponded to the optimal cutoff value. CONCLUSION: The abnormal title and the optimal cutoff value of ANA HEp-2 in the population was 1:160. Therefore, the dilution of 1:160 is the optimal screening dilution, with better specificity but without significantly compromising the sensitivity of the diagnostic test.

Detecção de células com fenótipo HPN por citometria de fluxo, utilizando análise multiparamétrica / Detection of PNH cells by flow cytometry, using multiparameter analysis

Introduction: The laboratory diagnosis of paroxysmal nocturnal hemoglobinuria (PNH), disease that is categorized by reduced synthesis of glycosylphosphatidylinositol (GPI) anchor, is based on the detection of blood cells deficient in GPI-anchored proteins by flow cytometry. PNH clones have been detected in patients with aplastic anaemia (AA) and myelodysplastic syndrome (MDS), with therapeutic implications. Objectives: To validate a sensitive assay for detection of GPI-anchored protein-deficient cells, by flow cytometry, and to analyze the clone frequency in AA and MDS patients. Methods: Samples from 20 AA patients, 30 MDS patients and 20 adult volunteers (control group) were analyzed using monoclonal antibodies to CD16, CD24, CD55 and CD59 (neutrophils); CD14 and CD55 (monocytes); CD55 and CD59 (erythrocytes); besides fluorescent aerolysin reagent (FLAER) (neutrophils and monocytes) and lineage markers. The proportions of PNH cells detected in neutrophils and monocytes, using different reagent combinations, were compared by analysis of variance (ANOVA) and Pearson's correlation. Results: PNH cells were detected in five (25%) AA patients, and the proportions of PNH cells varied from 0.14% to 94.84% of the analyzed events. PNH cells were not detected in the MDS patients. However, by the analysis of these samples, it was possible to identify the technical challenges caused by the presence of immature and dysplastic circulating cells. FLAER showed clear distinction of GPI-deficient cells. Conclusion: Multiparameter flow cytometry analysis offers high sensitivity and accuracy in the detection of subclinical PNH clones. FLAER shows excellent performance in detection of PNH neutrophils and monocytes...

Introdução: O diagnóstico laboratorial da hemoglobinúria paroxística noturna (HPN), doença caracterizada por deficiência de síntese da molécula de ancoragem glicosilfosfatidilinositol (GPI), baseia-se na detecção de células sanguíneas deficientes em proteínas ancoradas ao GPI, por citometria de fluxo. Clones de células com fenótipo HPN podem ser detectados em pacientes com anemia aplásica (AA) e síndrome mielodisplásica (SMD), com implicações terapêuticas. Objetivos: Validar técnica sensível para detecção de células HPN, por citometria de fluxo, e avaliar a frequência dos clones em pacientes com AA e SMD. Métodos: Amostras de 20 pacientes com AA, 30 pacientes com SMD e 20 voluntários (controles) foram analisadas, utilizando anticorpos monoclonais anti-CD16, CD24, CD55 e CD59 (neutrófilos); CD14 e CD55 (monócitos); e CD55 e CD59 (hemácias); além do reagente de aerolisina fluorescente (FLAER) (neutrófilos e monócitos) e marcadores de linhagem celular. A comparação do tamanho dos clones HPN detectados em neutrófilos e monócitos, pelas diferentes combinações de reagentes, foi realizada por análise de variância (ANOVA) e correlação de Pearson. Resultados: Em cinco (25%) pacientes com AA foram identificadas células HPN, em proporções entre 0,14% e 94,84% dos eventos analisados. O clone não foi detectado nos pacientes com SMD. Contudo, a análise dessas amostras permitiu evidenciar as dificuldades técnicas secundárias à presença de células imaturas e displásicas circulantes. O reagente FLAER propiciou separação precisa das células alteradas. Conclusão: A análise multiparamétrica por citometria de fluxo apresenta sensibilidade...

Deteccao de anticorpos antinucleares por imunofluorescencia indireta em celulas HEp-2: definindo a diluicao de triagem adequada para o diagnostico das doencas reumaticas autoimunes / Detection of anti-nuclear antibodies by indirect immunofluorescence on HEp-2 cells: setting the appropriate screening dilution for the diagnosis of autoimmune rheumatic diseases

Objetivo: Definir o título anormal e a diluição de triagem adequada para o teste de FAN (fator antinúcleo) por imunofluorescência indireta em células HEp-2 (FAN HEp-2). Métodos: Realizamos a pesquisa do FAN HEp-2 em amostras de soro de 126 indivíduos saudáveis. As amostras foram triadas na diluição de 1:80, e aquelas positivas diluídas até o título de 1:5120. O título anormal de FAN foi definido como aquele correspondente ao percentil 95 do teste nesta população. A sensibilidade dos diferentes títulos do FAN foi determinada em um grupo de 136 pacientes com diagnóstico de doença reumática autoimune, e a especificidade em um grupo de 118 pacientes com diagnóstico de outras doenças reumáticas. O valor de corte ótimo do teste foi determinado pelo estudo da curva ROC. Resultados: A frequência de FAN positivo em indivíduos saudáveis foi de 13,2%. Não houve diferença na frequência de resultados positivos de acordo com o gênero ou a idade. O título anormal do FAN foi definido como a diluição de 1:160. A diluição dos soros de 1:80 apresentou sensibilidade de 87,7% e especificidade de 67,8%, enquanto a diluição de 1:160 apresentou sensibilidade de 82% e especificidade de 73,7%. Pela análise da curva ROC, a diluição de 1:160 correspondeu ao valor de corte ótimo. Conclusão: O título anormal e o valor de corte ótimo do FAN HEp-2 na população avaliada foram de 1:160. A diluição de 1:160 é, portanto, a diluição de triagem ideal, com melhor especificidade, porém sem comprometimento significativo da sensibilidade diagnóstica do teste. .

Objective: To establish the abnormal title and the appropriate screening dilution for ANA (antinuclear antibodies) test by indirect immunofluorescence on HEp-2 cells (ANA HEp-2). Methods: An analysis of ANA Hep-2 in serum samples from 126 healthy individuals was performed. The samples were screened at a dilution of 1:80, and those positive were diluted to the title of 1:5120. The abnormal title of ANA was defined as that corresponding to the 95th percentile of the test in this population. The sensitivity of the different titles of antinuclear antibodies was determined in a group of 136 patients with a diagnosis of autoimmune rheumatic disease, and the specificity was determined in a group of 118 patients with other rheumatic diseases. The optimal cutoff value of the test was determined by ROC curve analysis. Results: The frequency of ANA positivity in healthy subjects was 13.2%. There was no difference in the frequency of positive results according to gender or age. The abnormal title of ANA was defined as the dilution of 1:160. The 1:80 dilution had sensitivity of 87.7% and specificity of 67.8%, while the 1:160 dilution had sensitivity of 82% and specificity of 73.7%. By ROC curve analysis, a dilution of 1:160 corresponded to the optimal cutoff value. Conclusion: The abnormal title and the optimal cutoff value of ANA HEp-2 in the population was 1:160. Therefore, the dilution of 1:160 is the optimal screening dilution, with better specificity but without significantly compromising the sensitivity of the diagnostic test. .

Viral immune evasion in dengue: toward evidence-based revisions of clinical practice guidelines.

UNLABELLED: Dengue, a leading cause of illness and death in the tropics and subtropics since the 1950׳s, is fast spreading in the Western hemisphere. Over 30% of the world׳s population is at risk for the mosquitoes that transmit any one of four related Dengue viruses (DENV). Infection induces lifetime protection to a particular serotype, but successive exposure to a different DENV increases the likelihood of severe form of dengue fever (DF), dengue hemorrhagic fever (DHF), or dengue shock syndrome (DSS). Prompt supportive treatment lowers the risk of developing the severe spectrum of Dengue-associated physiopathology. Vaccines are not available, and the most effective protective measure is to prevent mosquito bites. Here, we discuss selected aspects of the syndemic nature of Dengue, including its potential for pathologies of the central nervous system (CNS). We examine the fundamental mechanisms of cell-mediated and humoral immunity to viral infection in general, and the specific implications of these processes in the regulatory control of DENV infection, including DENV evasion from immune surveillance. In line with the emerging model of translational science in health care, which integrates translational research (viz., going from the patient to the bench and back to the patient) and translational effectiveness (viz., integrating and utilizing the best available evidence in clinical settings), we examine novel and timely evidence-based revisions of clinical practice guidelines critical in optimizing the management of DENV infection and Dengue pathologies. We examine the role of tele-medicine and stakeholder engagement in the contemporary model of patient centered, effectiveness-focused and evidence-based health care. ABBREVIATIONS: BBB - blood-brain barrier, CNS - central nervous system, DAMP - damage-associated molecular patterns, DENV - dengue virus, DF - dengue fever, DHF - dengue hemorrhagic fever, DSS - dengue shock syndrome, DALYs - isability adjusted life years, IFN-g - interferon-gamma, ILX - interleukinX, JAK/STAT - janus kinase (JAK) / Signal transducer and activator of transcription (STAT), LT - Escherichia coli heat-labile enterotoxin formulations deficient in GM1 binding by mutation (LT[G33D]), MCP-1 - monocyte chemotactic protein 1, M-CSF - macrophage colony-stimulating fact, MHC - major histocompatibility complex, MIF - macrophage migration inhibitory factor, [MIP-1]-α / -ß - macrophage inflammatory protein-1 alpha and beta, mAb - monoclonal antibody, NS1 - non-structural protein 1 of dengue virus, NK - natural killer cells, PAMP - pathogen-associated molecular patterns, PBMC - peripheral blood mononuclear cells, TBF-b - transforming growth factor-beta, TNF-α - tumor necrosis-alpha, VHFs - virus hemorrhagic fevers, WHO - World Health Organization.

Dombrock genotyping in Brazilian blood donors reveals different regional frequencies of the HY allele.

BACKGROUND: Dombrock blood group system genotyping has revealed various rearrangements of the Dombrock gene and identified new variant alleles in Brazil (i.e., DO*A-SH, DO*A-WL and DO*B-WL). Because of the high heterogeneity of the Brazilian population, interregional differences are expected during the investigation of Dombrock genotypes. OBJECTIVE: The present study aims to determine the frequencies of Dombrock genotypes in blood donors from Minas Gerais and compare the frequencies of the HY and JO alleles to those of another population in Brazil. METHODS: The frequencies of the DO alleles in Minas Gerais, a southeastern state of Brazil, were determined from the genotyping of 270 blood donors. Genotyping involved polymerase chain reaction and restriction fragment length polymorphism analysis to identify the 323G>T, 350C>T, 793A>G, and 898C>G mutations, which are related to the HY, JO, DO*A/DO*B, and DO*A-WL/DO*B-WL alleles, respectively. Moreover, the frequencies of rare HY and JO alleles were statistically compared using the chi-square test with data from another Brazilian region. RESULTS: The HY allele frequency in Minas Gerais (2.4%) was almost twice that of the JO allele (1.5%). The frequency of the HY allele was significantly higher (p-value = 0.001) than that in another Brazilian population and includes a rare homozygous donor with the Hy- phenotype. In addition, the DO*A-WL and DO*B-WL alleles, which were first identified in Brazil, were found in the state of Minas Gerais. CONCLUSIONS: The data confirm that the frequencies of DO alleles differ between regions in Brazil. The population of Minas Gerais could be targeted in a screening strategy to identify the Hy- phenotype in order to develop a rare blood bank.

Dombrock genotyping in Brazilian blood donors reveals different regional frequencies of the HY allele

Background: Dombrock blood group system genotyping has revealed various rearrangements of the Dombrock gene and identified new variant alleles in Brazil (i.e., DO*A-SH, DO*A-WL and DO*B-WL). Because of the high heterogeneity of the Brazilian population, interregional differences are expected during the investigation of Dombrock genotypes. Objective: The present study aims to determine the frequencies of Dombrock genotypes in blood donors from Minas Gerais and compare the frequencies of the HY and JO alleles to those of another population in Brazil. Methods: The frequencies of the DO alleles in Minas Gerais, a southeastern state of Brazil, were determined from the genotyping of 270 blood donors. Genotyping involved polymerase chain reaction and restriction fragment length polymorphism analysis to identify the 323G>T, 350C>T, 793A>G, and 898C>G mutations, which are related to the HY, JO, DO*A/DO*B, and DO*A-WL/DO*B-WL alleles, respectively. Moreover, the frequencies of rare HY and JO alleles were statistically compared using the chi-square test with data from another Brazilian region. Results: The HY allele frequency in Minas Gerais (2.4%) was almost twice that of the JO allele (1.5%). The frequency of the HY allele was significantly higher (p-value = 0.001) than that in another Brazilian population and includes a rare homozygous donor with the Hy- phenotype. In addition, the DO*A-WL and DO*B-WL alleles, which were first identified in Brazil, were found in the state of Minas Gerais. Conclusions: The data confirm that the frequencies of DO alleles differ between regions in Brazil. The population of Minas Gerais could be targeted in a screening strategy to identify the Hy- phenotype in order to develop a rare blood bank. .

Serum and salivary cortisol in the diagnosis of adrenal insufficiency and as a predictor of the outcome in patients with severe sepsis.

OBJECTIVES: To compare salivary with serum total cortisol in patients with severe sepsis, postoperative patients and healthy controls. MATERIALS AND METHODS: Serum total cortisol was determined by chemiluminescence immunoassay; salivary cortisol was determined by enzyme immunoassay. RESULTS: In patients with severe sepsis, median concentration of salivary cortisol was 14.0 and 2.6 higher than that of postoperative patients and healthy subjects. In postoperative patients, salivary cortisol was 5.4 times higher than in control patients. Serum total cortisol was also higher in patients with severe sepsis than in controls and postoperative patients. This increment, however, was much lower (2.33 and 1.64, respectively). Patients with a salivary cortisol greater than 7.2 µg/dL had a mortality rate of 80%, a statistically significant result when compared with the group with lower cortisol levels (Z = 2.38 and p < 0.05). CONCLUSIONS: Salivary cortisol in critically ill patients may be a better laboratory indicator of cortisol levels than serum total cortisol.

Serum and salivary cortisol in the diagnosis of adrenal insufficiency and as a predictor of the outcome in patients with severe sepsis / Avaliação do cortisol sérico e salivar no diagnóstico da insuficiência adrenal e como parâmetro preditor da evolução de pacientes com sepse grave

OBJECTIVES: To compare salivary with serum total cortisol in patients with severe sepsis, postoperative patients and healthy controls. MATERIALS AND METHODS: Serum total cortisol was determined by chemiluminescence immunoassay; salivary cortisol was determined by enzyme immunoassay. RESULTS: In patients with severe sepsis, median concentration of salivary cortisol was 14.0 and 2.6 higher than that of postoperative patients and healthy subjects. In postoperative patients, salivary cortisol was 5.4 times higher than in control patients. Serum total cortisol was also higher in patients with severe sepsis than in controls and postoperative patients. This increment, however, was much lower (2.33 and 1.64, respectively). Patients with a salivary cortisol greater than 7.2 µg/dL had a mortality rate of 80 percent, a statistically significant result when compared with the group with lower cortisol levels (Z = 2.38 and p < 0.05). CONCLUSIONS: Salivary cortisol in critically ill patients may be a better laboratory indicator of cortisol levels than serum total cortisol.

OBJETIVOS: Comparar cortisol salivar com sérico total em pacientes com sepse grave, em pós-operatório e controles normais. MATERIAIS E MÉTODOS: Cortisol sérico total foi determinado por imunoensaio quimioluminescente e cortisol salivar por imunoensaio enzimático. RESULTADOS: Em pacientes com sepse grave, a mediana do cortisol salivar foi 14,0 e 2,6 vezes maior que dos pacientes em pós-operatório e saudáveis. Nos pacientes em pós-operatório, cortisol salivar foi 5,4 vezes maior que o controle. Cortisol sérico total também foi maior em pacientes com sepse grave que nos saudáveis e pós-operatórios, porém, esse incremento foi bem menor (2,33 e 1,64, respectivamente). Pacientes com cortisol salivar superior a 7,2 µg/dL tiveram mortalidade de 80 por cento, com significância estatística, quando comparado com os pacientes com níveis mais baixos (Z = 2,38 e p < 0,05). CONCLUSÕES: Cortisol salivar em pacientes críticos parece ser um melhor marcador da atividade glicocorticoide que o cortisol sérico total.

Quantification of CD8(+)CD38(+) T lymphocytes by flow cytometry does not represent a good biomarker to monitor the reactivation of cytomegalovirus infection after allogeneic hematopoietic stem cell transplantation.

BACKGROUND: Infection/reactivation of cytomegalovirus is a major cause of morbidity and mortality in immunocompromised transplant patients. It has already been observed in kidney and liver transplantation patients that cytomegalovirus disease is accompanied by significant increases in circulating CD8(+)CD38(+) T lymphocytes. There are no reports that study CD8(+)CD38(+) T lymphocytes to monitor/diagnose cytomegalovirus disease in hematopoietic stem cell transplantation patients. OBJECTIVE: The aim of this study was to evaluate some cellular activation markers on circulating mononuclear cells (CD38 and HLA-DR) in patients submitted to hematopoietic stem cell transplantation and to establish any correlation with cytomegalovirus disease as diagnosed by antigenemia. METHODS: Blood samples of 15 transplant patients were analyzed by flow cytometry using anti-CD3, anti-CD4, anti-CD8, anti-CD38, CD16, CD56 and anti-HLA-DR monoclonal antibodies and the results were evaluated in respect to cytomegalovirus antigenemia measured by indirect immunofluorescence. Minitab for Windows was used for statistical analysis and a p-value < 0.05 was considered significant. RESULTS: Patients with positive antigenemia did not show any significant increase in the percentages of cells expressing the CD38 or HLADR activation markers when compared to patients with negative antigenemia. On the contrary, all patients showed high percentages of these cells independent of the presence of cytomegalovirus disease. CONCLUSIONS: This study suggests that the investigation of these lymphocyte sub-populations in patients submitted to hematopoietic stem cell transplantation does not seem to contribute to the early identification of cytomegalovirus disease.

Quantification of CD8+CD38+ T lymphocytes by flow cytometry does not represent a good biomarker to monitor the reactivation of cytomegalovirus infection after allogeneic hematopoietic stem cell transplantation

BACKGROUND: Infection/reactivation of cytomegalovirus is a major cause of morbidity and mortality in immunocompromised transplant patients. It has already been observed in kidney and liver transplantation patients that cytomegalovirus disease is accompanied by significant increases in circulating CD8+CD38+ T lymphocytes. There are no reports that study CD8+CD38+ T lymphocytes to monitor/diagnose cytomegalovirus disease in hematopoietic stem cell transplantation patients. OBJECTIVE: The aim of this study was to evaluate some cellular activation markers on circulating mononuclear cells (CD38 and HLA-DR) in patients submitted to hematopoietic stem cell transplantation and to establish any correlation with cytomegalovirus disease as diagnosed by antigenemia. METHODS: Blood samples of 15 transplant patients were analyzed by flow cytometry using anti-CD3, anti-CD4, anti-CD8, anti-CD38, CD16, CD56 and anti-HLA-DR monoclonal antibodies and the results were evaluated in respect to cytomegalovirus antigenemia measured by indirect immunofluorescence. Minitab for Windows was used for statistical analysis and a p-value < 0.05 was considered significant. RESULTS: Patients with positive antigenemia did not show any significant increase in the percentages of cells expressing the CD38 or HLADR activation markers when compared to patients with negative antigenemia. On the contrary, all patients showed high percentages of these cells independent of the presence of cytomegalovirus disease. CONCLUSIONS: This study suggests that the investigation of these lymphocyte sub-populations in patients submitted to hematopoietic stem cell transplantation does not seem to contribute to the early identification of cytomegalovirus disease.