Resumo em Inglês:

BACKGROUND: Plasma components of group O blood donations are rarely submitted to ABO antibody titrations even though it is well known that passively acquired antibodies may destroy the recipient's own red cells and tissue grafts. OBJECTIVE: Thus, group O donations stratified by gender and age were randomly titrated to identify the best source of products for apheresis and exsanguinous transfusion. METHODS: Samples from 603 blood donors were tested by ABO antibody titration using the conventional tube technique at room temperature. ABO antibody levels higher than 64 were considered high. After correction for gender, statistical analyses were performed using the Fisher exact and Kruskal-Wallis tests. RESULTS: Most donors in the blood bank were male (65.7%). ABO antibody titers ranged from 1 to 2048. The estimations of prevalence for the titers were: anti-A,B < 128 = 86.9% and > 128 = 2.16%; Anti-A > 128 = 9.29% and anti-B > 128 = 4.81%. Low mean titers for both anti-A and anti-B antibodies were found in over 50-year-old men (p-value = 0.040). High anti-B antibody levels were found in young women (p-value = 0.002). CONCLUSION: This study confirms that over 50-year-old O group men should be selected as blood donors in non-identical ABO transfusion situations. Also, titration of ABO antibodies in blood banks will increase safety in non-identical ABO transfusions.

Resumo em Inglês:

BACKGROUND: Confidential unit exclusion remains a controversial strategy to reduce the residual risk of transfusion-transmitted infections. OBJECTIVE: This study aimed to analyze confidential unit exclusion from its development in a large institution in light of confidential donation confirmation. METHODS: Data of individuals who donated from October 1, 2008 to December 31, 2009 were analyzed in a case-control study. The serological results and sociodemographic characteristics of donors who did not confirm their donations were compared to those who did. Variables with p-values < 0.20 in univariate analysis were included in a logistic multivariate analysis. RESULTS: In the univariate analysis there was a statically significant association between positive serological results and response to confidential donation confirmation of "No". Donation type, (firsttime or return donor - OR 1.69, CI 1.37-2.09), gender (OR 1.66, CI 1.35-2.04), education level (OR 2.82, CI 2.30-3.47) and ethnic background (OR 0.67, CI 0.55-0.82) were included in the final logistic regression model. In all logistic regression models analyzed, the serological suitability and confidential donation confirmation were not found to be statistically associated. The adoption of new measures of clinical classification such as audiovisual touch-screen computer-assisted self-administered interviews might be more effective than confidential unit exclusion in the identification of donor risk behavior. The requirement that transfusion services continue to use confidential unit exclusion needs to be debated in countries where more specific and sensitive clinical and serological screening methods are available. CONCLUSION: Our findings suggest that there are not enough benefits to justify continued use of confidential donation confirmation in the analyzed institution.

Resumo em Inglês:

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.

Resumo em Inglês:

BACKGROUND: Recently, single nucleotide polymorphisms (SNPs) were identified in the promoter region of the perforin gene (PRF1) and it was found that the -398T mutant allele is correlated with lower amounts of protein in circulating CD8+ cytotoxic T lymphocytes. OBJECTIVE: The aim of this study was to investigate the presence of the -398C/T polymorphism in the perforin gene in oncohematological patients. Methods: Sixty-two patients with hematological malignancies treated at the teaching hospital of the Universidade Federal do Triângulo Mineiro were invited to participate in this study. The identification of the polymorphism was achieved by amplification using polymerase chain reaction, digestion using the TaqI enzyme and electrophoresis in 1% agarose gel. RESULTS: The heterozygous -398C/T polymorphism was identified in 16.7% patients with acute lymphoblastic leukemia, 40% with multiple myeloma, 50% with essential thrombocythemia, 14.3% with Hodgkin's disease, 7.7% with non-Hodgkin lymphoma and 33.3% with chronic lymphocytic leukemia. The homozygous mutant allele was identified in one mulatto individual (25%) with myelodysplastic syndrome. When Afro-Brazilian and Whites were analyzed together, there was a higher frequency of the -398T allele in patients than in healthy individuals (p-value = 0.0291). CONCLUSION:One patient was homozygous for the -398T allele. Based on these findings, further studies should be conducted to assess whether the presence of this polymorphism may be a risk factor for the development of hematologic malignancies.

Resumo em Inglês:

OBJECTIVE: To evaluate the quality of healthcare provided to sickle cell disease children by primary healthcare services in a region of high prevalence. METHODS: A cross-sectional, descriptive study was performed by interviewing members of families with sickle cell disease children. The children had been identified from the Neonatal Screening Program in Minas Gerais state over the last 12 years in towns of the Montes Claros-Bocaiuva microregion. A structured questionnaire specially developed for this study and based on three axes was used: indicators of the child's health (immunization, growth and development, prophylaxis antibiotic therapy), perception of care by the family (health education and accessibility) and knowledge of the family about the disease. RESULTS: Sixty-three of 71 families with children identified as having sickle cell disease were interviewed. The predominant genotypes were Hb SS (44.4%) and Hb SC (41.2%). Adequate monitoring of growth and development was recorded for the first year of life in 23 children (36.6%) and for the second year of life in 18 children (28.6%). The basic vaccination schedule was completed by 44 children (69.8%) but 62 vaccination record cards (98.4%) identified delays of special vaccines. Regular use of prophylactic penicillin was reported by 55 caregivers (87.3%). The family's perception of the care provided suggests poor accessibility to health services and lack of opportunities to answer doubts. The average performance of families in knowledge testing was 59.8%. CONCLUSION: The quality of healthcare is unsatisfactory. The care provided to children with sickle cell disease in primary healthcare services needs improvements.

Resumo em Inglês:

BACKGROUND: New criteria for the diagnosis and classification of chronic graft-versus-host disease were developed in 2005 for the purpose of clinical trials with a consensus sponsored by the National Institute of Health. OBJECTIVES: The aim of this study is to present the results of a multicenter pilot study performed by the Brazil-Seattle chronic graft-versus-host disease consortium to determine the feasibility of using these criteria in five Brazilian centers. METHODS: The study was performed after translation of the consensus criteria into Portuguese and training. A total of 34 patients with National Institute of Health chronic graft-versus-host disease were enrolled in the pilot study between June 2006 and May 2009. RESULTS: Of the 34 patients, 26 (76%) met the criteria of overlap syndrome and eight (24%) the classic subcategory. The overall severity of disease was moderate in 21 (62%) and severe in 13 (38%) patients. The median time from transplant to onset of chronic graft-versus-host disease was 5.9 months (Range: 3 - 16 months); the median time for the overlap syndrome subcategory was 5.9 months (Range: 3 - 10 months) and for the classic subcategory, it was 7.3 months (Range: 3 - 16 months). At a median follow up of 16.5 months (Range: 4 - 39 months), overall survival was 75%. CONCLUSIONS: It was feasible to use the National Institute of Health consensus criteria for the diagnosis and scoring of chronic graft-versus-host disease in a Brazilian prospective multicenter study. More importantly, a collaborative hematopoietic cell transplantation network was established in Brazil offering new opportunities for future clinical trials in chronic graft-versus-host disease and in other areas of research involving hematopoietic stem cell transplantation.

Resumo em Inglês:

Chronic myeloproliferative neoplasms arise from clonal proliferation of hematopoietic stem cells. According to the World Health Organization myeloproliferative neoplasms are classified as: chronic myelogenous leukemia, polycythemia vera, essential thrombocythemia, primary myelofibrosis, chronic neutrophilic leukemia, chronic eosinophilic leukemia, hypereosinophilic syndrome, mast cell disease, and unclassifiable myeloproliferative neoplasms. In the revised 2008 WHO diagnostic criteria for myeloproliferative neoplasms, mutation screening for JAK2V617F is considered a major criterion for polycythemia vera diagnosis and also for essential thrombocythemia and primary myelofibrosis, the presence of this mutation represents a clonal marker. There are currently two hypotheses explaining the role of the JAK2V617F mutation in chronic myeloproliferative neoplasms. According to these theories, the mutation plays either a primary or secondary role in disease development. The discovery of the JAK2V617F mutation has been essential in understanding the genetic basis of chronic myeloproliferative neoplasms, providing some idea on how a single mutation can result in three different chronic myeloproliferative neoplasm phenotypes. But there are still some issues to be clarified. Thus, studies are still needed to determine specific molecular markers for each subtype of chronic myeloproliferative neoplasm.

Resumo em Inglês:

Hemagglutination is widely used in transfusion medicine and depends on several factors including antigens, antibodies, electrical properties of red blood cells and the environment of the reaction. Intermolecular forces are involved in agglutination with cell clumping occurring when the aggregation force is greater than the force of repulsion. Repulsive force is generated by negative charges on the red blood cell surface that occur due to the presence of the carboxyl group of sialic acids in the cell membrane; these charges create a repulsive electric zeta potential between cells. In transfusion services, specific solutions are used to improve hemagglutination, including enzymes that reduce the negative charge of red blood cells, LISS which improves the binding of antibodies to antigens and macromolecules that decrease the distance between erythrocytes. The specificity and sensitivity of immunohematological reactions depend directly on the appropriate use of these solutions. Knowledge of the electrical properties of red blood cells and of the action of enhancement solutions can contribute to the immunohematology practice in transfusion services.

Resumo em Inglês:

Imatinib has proved to be effective in the treatment of chronic myeloid leukemia, but plasma levels above 1,000 ng/mL must be achieved to optimize activity. Therapeutic drug monitoring of imatinib is useful for patients that do not present clinical response. There are several analytical methods to measure imatinib in biosamples, which are mainly based on liquid chromatography with mass spectrometric or diode array spectrophotometric detection. The former is preferred due to its lower cost and wider availability. The present manuscript presents a review of the clinical and analytical aspects of the therapeutic drug monitoring of imatinib in the treatment of chronic myeloid leukemia. The review includes references published over the last 10 years. There is evidence that the monitoring of plasmatic levels of imatinib is an useful alternative, especially considering the wide pharmacokinetic variability of this drug.

Resumo em Inglês:

The globin family has long been defined by myoglobin and hemoglobin, proteins with the functions of oxygen storage and transportation, respectively. Recently, two new members of this family were discovered: neuroglobin present in neurons and retinal cells and cytoglobin found in various types of tissue. The increased expression of these proteins in hypoxic conditions first suggested a role in oxygen supply. However structural and functional differences, such as the hexacoordinated heme, a high autoxidation rate and different concentrations between different cellular types, have dismissed this hypothesis. The protective role of these globins has already been established. In vitro and in vivo studies have demonstrated increased survival of neurons under stress in the presence of neuroglobin and increased resistance to neurodegenerative diseases. However the mechanism remains unknown. Functions, including detoxification of nitric oxide, free radical scavenging and as an antioxidant and signaling of apoptosis, have also been suggested for neuroglobin and an antifibrotic function for cytoglobin.

Resumo em Inglês:

Rosai-Dorfman disease is a self-limiting condition caused by histiocyte proliferation within the sinusoids of lymph nodes and in extranodal tissue. It is a rare disease, particularly in children, that progresses with extensive lymphadenopathy. This paper reports on the case of a 2-year-old child with progressive cervical lymphadenopathy associated with persistent fever and radiological findings suggestive of lymphoma. Histopathological and immunohistochemistry studies of a lymph node biopsy established the diagnosis of Rosai-Dorfman disease. Both lymphadenopathy and fever resolved spontaneously.