Global Proteomics Analysis of Bone Marrow: Establishing Talin-1 and Centrosomal Protein of 55 kDa as Potential Molecular Signatures for Myelodysplastic Syndromes.

Myelodysplastic syndrome (MDS) is a hematological disorder characterized by abnormal stem cell differentiation and a high risk of acute myeloid leukemia transformation. Treatment options for MDS are still limited, making the identification of molecular signatures for MDS progression a vital task. Thus, we evaluated the proteome of bone marrow plasma from patients (n = 28) diagnosed with MDS with ring sideroblasts (MDS-RS) and MDS with blasts in the bone marrow (MDS-EB) using label-free mass spectrometry. This strategy allowed the identification of 1,194 proteins in the bone marrow plasma samples. Polyubiquitin-C (UBC), moesin (MSN), and Talin-1 (TLN1) showed the highest abundances in MDS-EB, and centrosomal protein of 55 kDa (CEP55) showed the highest relative abundance in the bone marrow plasma of MDS-RS patients. In a follow-up, in the second phase of the study, expressions of UBC, MSN, TLN1, and CEP55 genes were evaluated in bone marrow mononuclear cells from 45 patients by using qPCR. This second cohort included only seven patients from the first study. CEP55, MSN, and UBC expressions were similar in mononuclear cells from MDS-RS and MDS-EB individuals. However, TLN1 gene expression was greater in mononuclear cells from MDS-RS (p = 0.049) as compared to MDS-EB patients. Irrespective of the MDS subtype, CEP55 expression was higher (p = 0.045) in MDS patients with abnormal karyotypes, while MSN, UBC, and TALIN1 transcripts were similar in MDS with normal vs. abnormal karyotypes. In conclusion, proteomic and gene expression approaches brought evidence of altered TLN1 and CEP55 expressions in cellular and non-cellular bone marrow compartments of patients with low-risk (MDS-RS) and high-risk (MDS-EB) MDSs and with normal vs. abnormal karyotypes. As MDS is characterized by disrupted apoptosis and chromosomal alterations, leading to mitotic slippage, TLN1 and CEP55 represent potential markers for MDS prognosis and/or targeted therapy.

c 9253-6T > c REV3L: A novel marker of poor prognosis in Myelodysplastic syndrome

Myelodysplastic syndromes (MDS) are a heterogeneous group of hematological malignancies characterized by dysplasias, ineffective hematopoiesis and risk of acute myeloid leukemia transformation. Approximately 90% of MDS patients present mutations in genes involved in various cell signaling pathways. Specialized DNA polymerases, such as POLN, POLI, POLK, POLQ, POLH, POLL and REV3L, insert a nucleotide opposite replication-blocking DNA lesions in an error-prone manner and, in this way, sometimes can actively promote the generation of mutation. For the best of our knowledge, has not been described the mutations of these genes in MDS. DNA target sequencing CDS regions of the REV3L gene was performed in a 58-year-old man diagnosed as High Risk Myelodysplastic Syndrome. The patient presented very low hemoglobin, increased number of blasts, karyotype:47,XY,+8[6]/47,XY,del(7)(q32),+8[7], no response to hypomethylating therapy (decitabine), all markers of poor prognosis. Target sequencing identified a mutation c.9253-6T>C REV3L (Substitution - intronic) with VAF (variant allele frequency) = 16% considered pathogenic according to Functional Analysis through. Hidden Markov Models (FATHMM). This is the first evidence of REV3L mutation in MDS and, of utmost importance, associated with poor prognosis.

Immune Dysregulation and Recurring Mutations in Myelodysplastic Syndromes Pathogenesis.

Myelodysplastic syndromes (MDS) are clonal stem cell malignancies characterized by ineffective hematopoiesis leading to peripheral cytopenias and variable risk of progression to acute myeloid leukemia. Inflammation is associated with MDS pathogenesis. Several cytokines, reactive species of oxygen/nitrogen and growth factors are directly or indirectly involved in dysfunction of the MDS bone marrow (BM) microenvironment. Mutations in genes mainly regulating RNA splicing, DNA methylation and chromatin accessibility, transcription factors, signal transduction and the response to DNA damage contribute to ineffective hematopoiesis, genomic instability and MDS development. The inflammation-associated DNA damage in hematopoietic stem cells may also contribute to MDS development and progression with aggressive clinical characteristics. Many studies have aimed at clarifying mechanisms involved in the activity of immature myeloid cells as powerful modulators of the immune response and their correlation with aging, autoimmunity, and development of cancer. In this review, we explore recent advances and accumulating evidence uniting immune dysregulation, inflammaging and recurring mutations in the pathogenesis of MDS.

c.9253-6T>c REV3L: A novel marker of poor prognosis in Myelodysplastic syndrome.

Myelodysplastic syndromes (MDS) are a heterogeneous group of hematological malignancies characterized by dysplasias, ineffective hematopoiesis and risk of acute myeloid leukemia transformation. Approximately 90% of MDS patients present mutations in genes involved in various cell signaling pathways. Specialized DNA polymerases, such as POLN, POLI, POLK, POLQ, POLH, POLL and REV3L, insert a nucleotide opposite replication-blocking DNA lesions in an error-prone manner and, in this way, sometimes can actively promote the generation of mutation. For the best of our knowledge, has not been described the mutations of these genes in MDS. DNA target sequencing CDS regions of the REV3L gene was performed in a 58-year-old man diagnosed as High Risk Myelodysplastic Syndrome. The patient presented very low hemoglobin, increased number of blasts, karyotype:47,XY,+8[6]/47,XY,del(7)(q32),+8[7], no response to hypomethylating therapy (decitabine), all markers of poor prognosis. Target sequencing identified a mutation c.9253-6T>C REV3L (Substitution - intronic) with VAF (variant allele frequency)=16% considered pathogenic according to Functional Analysis through. Hidden Markov Models (FATHMM). This is the first evidence of REV3L mutation in MDS and, of utmost importance, associated with poor prognosis.

Observational study of multiple myeloma in Latin America.

Relatively little is known about the outcomes of multiple myeloma in Latin America, a world region where incorporation of novel agents is generally slow. In the current retrospective-prospective study, we aimed to describe the patterns of care and treatment results in five Latin American countries. Between April 2007 and October 2009, patients who had been diagnosed from January 2005 to December 2007 were registered at 23 institutions from Argentina, Brazil, Chile, Mexico, and Peru. We divided patients into two cohorts, according to transplantation eligibility, and analyzed them with regard to first-line treatment and overall survival (OS). We analyzed a total of 852 patients, 46.9 % of whom were female. The median follow-up was 62 months. Among transplantation-ineligible patients (N = 461), the mean age was 67.4 years, approximately one third of patients received a thalidomide-based treatment in the first line, and the median OS was 43.0 months. Transplantation-eligible patients (N = 391) had a mean age of 54.7 years and a median OS of 73.6 months. Autologous transplantation was performed in 58.6 % of the patients for whom this procedure was initially planned and in only 26.9 % of the overall patients. Our long-term results reflect the contemporary literature for patients with multiple myeloma treated with autologous transplantation and thalidomide-based regimens in clinical trials and observational studies. However, further efforts are needed to approve and incorporate novel agents in Latin American countries, as well as to increase access to transplantation, in order to achieve the expected improvements in patient outcomes.

Myelodysplastic syndromes in South America: a multinational study of 1080 patients.

There are previously reported data describing differences between Asian and European patients with Myelodysplastic Syndromes (MDS), few direct comparisons based on cancer registration characteristics or using cohorts to validate scoring systems. This is the first study from South-America, which attempts to describe demographic, clinical features, and outcome of MDS patients. We retrospectively analyzed 1,080 patients with de novo MDS from Argentina (635), Brazil (345), and Chile (100). Chilean patients were younger (P = 0.001) with female preponderance (P = 0.071). Brazilian series showed a higher predominance of RARS subtype regarding FAB and WHO classifications (P < 0.001). Hemoglobin levels were significantly lower in Brazilian and Chilean series (P < 0.001), and Chilean series also showed a lower platelet count (P = 0.028), with no differences concerning the neutrophil count, % BM blast, and the distribution of cytogenetic risk groups (P > 0.05). Chilean series depicted a lower overall survival (OS; 35 months vs. 56 months-Argentine; 55 months-Brazil, P = 0.030), which was consistent with a higher predominance of the high-risk group according both to the IPSS and IPSS-R (P = 0.046 and P < 0.001). The IPSS-R system and its variables showed a good reproducibility to predict clinical outcome for the whole South-American population. Epidemiological and clinical characteristics, distribution among prognostic subgroups, the OS, and the access to disease modifying therapies were more similar between Argentinean and Brazilian compared with Chilean MDS series. This will need further analysis in a larger group of patients. Descriptive and comparative studies are necessary to establish epidemiological features useful for public health attitudes to generate suitable therapeutic schemes.

Tissue doppler echocardiography detects preclinical markers of cardiac lesion in MDS patients.

Myelodysplastic syndrome (MDS) is a clonal hematopoietic stem cell disorder of elderly people. Cardiac dysfunction is a marker of grim prognosis in MDS. We evaluated cardiac dysfunction of MDS patients with or without transfusion dependency by tissue doppler echocardiography. We found the average values of ventricular end-systolic and end-diastolic volumes in transfusion dependency MDS group higher than others. These results were strongly correlated to hemoglobin levels. Tissue Doppler Echocardiography should be routinely performed in MDS patients to detect preclinical cardiac alterations and prevent more heart insults in this group of chronic anemic aged patients.

Síndromes mielodisplásicas e mielodisplásicas/mieloproliferativas / Myelodysplastic syndromes and diseases with myelodysplastic and myeloproliferative features

As síndromes mielodisplásicas (SMD) representam um grupo heterogêneo de doenças hematológicas caracterizadas por hematopoese ineficaz e risco aumentado de evolução para leucemia mieloide aguda. Neste artigo educativo são apresentados aspectos gerais da sua fisiopatologia, diagnóstico, apresentação histopatológica e seu papel no diagnóstico diferencial, classificação e estratificação prognóstica. Ressalta-se a importância da avaliação clínica e laboratorial, que inclui avaliação do sangue periférico e medula óssea: morfologia - aspirado medular e biópsia óssea -, citogenética, imunofenotipagem, além de dados evolutivos. O diagnóstico definitivo, em especial nos casos de baixo risco, deve considerar a exclusão de causas não clonais que podem, através de alterações dismielopoéticas reativas, simular a mielodisplasia, tais como infecções virais, principalmente pelo HIV. A nova classificação revisada da Organização Mundial da Saúde (OMS-2008) é apresentada e discutida.

Myelodysplastic syndromes (MDS) represent a heterogeneous group of hematologic disorders characterized by ineffective hematopoiesis and an increased risk of developing acute myeloid leukemia. In this educational article the general aspects of the physiopathology, diagnosis, and histopathological features of MDS and their role in differential diagnosis, classification and prognostic categorization are presented. The importance of clinical and laboratory evaluations, including peripheral blood and bone marrow analyses, including morphology - aspirate and core biopsy, cytogenetics, immunophenotype and careful serial follow-up is emphasized. Definite diagnosis of MDS, especially in low-risk subtypes, should consider the exclusion of disorders with reactive bone marrow alterations, such as viral infections for example HIV. The new revised World Health Organization (WHO-2008) classification is presented and discussed.

Management of transfusional iron overload in Latin America: current outlook and expert panel recommendations.

The results of a meeting of physicians convening in Latin America to develop expert opinions on the diagnosis, monitoring and treatment of iron overload are as follows. An accurate diagnosis can be obtained by neonatal screening for haemoglobinopathies, especially sickle cell disease and the thalassaemias. Disease-specific registries are needed to demonstrate the extent of the problem to health authorities. Disparities in the quantity and quality of blood products must be addressed, and uniform transfusion guidelines are necessary. Serum ferritin level is a feasible marker for iron overload in the region, while magnetic resonance imaging assessment can improve the diagnosis and monitoring of cardiac and liver iron content. Medical specialists, including radiologists, pathologists and others, and health authorities, can help to implement these methods and provide adequate resources. The recently available oral deferasirox can be used to conveniently administer iron chelation to transfusional iron-overloaded patients.

Efeito da bomba de infusão de soluções sobre o grau de hemólise em concentrados de hemácias / Effect of the infusion pumps of solutions on the degree of hemolysis

A lise das hemácias, de causa imune ou não imune, pode provocar a elevação da hemoglobina plasmática induzindo efeitos deletérios principalmente nos rins e no sistema cardiovascular. Este trabalho objetiva evidenciar o possível efeito hemolítico induzido pelo trauma mecânico provocado pela passagem das hemácias em diferentes modelos de bombas de infusão de soluções, em concentrados de hemácias com até dez dias de armazenamento, preparados com Sag-Manitol. Foram utilizados três modelos de bombas (Nutrimat, Infusomat Compact e Volumed), com quatro aparelhos de cada modelo, testados em três velocidades de infusão (120 mL/h, 240 mL/h e 360 mL/h). Os parâmetros utilizados para evidenciar o grau de hemólise foram o percentual de hemólise e os níveis de hemoglobina e potássio livres no plasma. As amostras foram coletadas antes da passagem do concentrado de hemácias pelas bombas, na metade do tempo de infusão e no final da infusão, nas diferentes velocidades. Não ocorreu variação significativa entre os valores dos parâmetros analisados nas amostras controle e naquelas coletadas nas diferentes velocidades, marcas de bombas, mecanismos de infusão entre as bombas da mesma marca e entre os diferentes tempos de infusão. A principal variação encontrada foi relacionada com o potássio livre, devido à variação inerente aos próprios concentrados, o que foi evidenciado ao se compararem os valores obtidos nas amostras controle e nas amostras colhidas nos tempos médio e final em cada bomba. De acordo com os resultados obtidos, não houve alteração estatisticamente significativa do percentual de hemólise após a passagem pelas bombas de infusão nos modelos analisados.

The lyses of red blood cells, both for immune or non-immune reasons, can cause an elevation in plasmatic hemoglobin, inducing harmful effects mainly in the kidneys and cardiovascular system. This work aims at identifying the possible hemolytic effect, related to mechanical trauma due to the use of different models of infusion pumps, on red blood cells transfused after up to ten days of storage. Three models of pumps were studied (Nutrimat, Infusomat Compact and Volumed), (four devices of each model) with three infusion speeds being tested (120 mL/h, 240 mL/h and 360 mL/h). The parameters used to report the degree of hemolysis were the percentile of hemolysis, hemoglobin levels and free potassium in the plasma. Samples were collected before infusion of red blood cells using the pumps, half way through infusion (1/2 T) and at the end of infusion (T), for the three different speeds. Significant variations were not seen in the analyzed parameters between the control samples and those collected at different speeds, using different models of pumps and infusion mechanisms and among pumps of the same brand and at different infusion times. The greatest variation found involved free potassium, probably due to the different levels found in red blood cell concentrates seen when control samples were compared to values obtained half way through and at the end of infusion for each pump. In agreement with the obtained results changes in the percentile of hemolysis were not found after infusion of the cells using the different infusion pumps.

Síndromes mielodisplásticas: diagnóstico de exclusão / Myelodysplastic syndromes: diagnosis by exclusion

As síndromes mielodisplásticas são comuns nos indivíduos com idade superior a 60 anos e se apresentam laboratorialmente com macrocitose isolada, anemia, citopenias isoladas ou combinadas e alterações morfológicas na medula óssea. O diagnóstico depende da exclusão de causas não clonais e reversíveis. Especialmente nas fases mais precoces da doença, na ausência de excesso de blastos, sideroblastos em anel ou alteração citogenética clonal, o diagnóstico requer um protocolo de exclusão. A exposição recente a agentes tóxicos ou drogas citostáticas, a deficiência de vitamina B12 e ácido fólico e o uso recente de fatores de crescimento são considerados fatores de exclusão absolutos. O etilismo, a anemia da doença crônica, distúrbios metabólicos, hormonais, auto-imunes e infecções virais devem ser excluídos ou interpretados com cautela. Outras doenças da célula-tronco hematopoética devem ser consideradas, sobretudo na SMD hipocelular. Em alguns casos, um período mínimo de seis meses de seguimento é necessário.

Myelodysplastic syndromes are common in elderly people. Laboratory presentation includes isolated macrocytosis, anemia, isolated or combined cytopenias and dysplastic bone marrow. Diagnosis depends on exclusion of non-clonal and reversible disorders. Especially in lowest grade of the disease, with no blast excess, no ringed sideroblasts, no clonal cytogenetic abnormalities the diagnosis requires an exclusion protocol. Recent exposure to toxin, cytotoxic drugs or growth factor therapy and vitamin B12 or folate deficiency are considered absolute exclusion factors precluding the definite diagnosis. Alcohol abuse, chronic inflammatory states, auto-immune disorders, metabolic dysfunctions, hormonal disorders and viral infections must all be ruled out or interpreted with caution. Some diseases of the pluripotential stem cell must also be considered especially in hypocellular MDS. Moreover, in some cases a 6-month follow-up is necessary before a diagnosis be established.

Células dendríticas foliculares: imunofenotipagem no linfoma de Hodgkin clássico esclerose nodular / Dendritic follicular cells: immunophenotyping in classic Hodgkin's lymphoma nodular sclerosis

O linfoma de Hodgkin clássico esclerose nodular (LHCEN), de origem linfóide da célula B do centro germinativo (CG), apresenta agregados de células dendríticas foliculares (CDF), célula Hodgkin/Reed Sternberg e variantes, células B formando complexos relacionados ao CG, sugerindo uma associação entre esclerose nodular e formação do centro germinativo. O objetivo desse estudo foi avaliar a célula dendrítica folicular, por imunofenotipagem com o anticorpo fascina, em biópsia de linfonodo periférico ou massa do mediastino de pacientes com LHCEN previamente diagnosticados, procurando identificar critérios como fatores prognósticos. Foram selecionados 38 pacientes, 55,2 por cento do sexo masculino com relação M:F de 1,23: 1 e a idade com média de 29,3 anos; 52,6 por cento em estádios clínicos I-II, sendo 68,4 por cento com sintomas B. Foram analisados 38 espécimes de biópsias, sendo 57,9 por cento do subtipo esclerose nodular II. O estudo imuno-histoquímico mostrou 100 por cento de positividade para o CD30 e 68,4 por cento para o CD15. As CDFs foram identificadas pelo anticorpo fascina, considerado padrão-ouro, através da técnica imunoenzimática indireta peroxidase-anti-peroxidase estreptavidina-avidina-biotina (PAP-Strept ABC), realizada em lâminas pré-tratadas do material de biópsia incluído em blocos de parafina. Foi evidenciado padrão CDF1 em 7,9 por cento, CDF2 em 47,4 por cento e CDF3 em 44,7 por cento. Não houve relação entre a presença da CDF e sexo, idade, estádio clínico e resposta ao tratamento, mas foi demonstrada uma tendência para associação (p=0,056) entre CDF os subtipos LHCEN. Os pacientes com presença de célula dendrítica folicular foram acompanhados por maior período, com média de 32,9 meses, com associação estatisticamente significativa (p=0,001).

Classic nodular sclerosis HodgkinÆs lymphoma (CNSHL) is a lymphoid neoplasm of germinal center (GC) B cells, presenting with aggregates of follicular dendritic cells (FDC), Hodgkin/Reed Sternberg cells and variants and B cells forming complexes related to the GC. This suggests an association between nodular sclerosis and GC formation. The goal of this study was to evaluate the follicular dendritic cells by immunophenotyping with fascin from lymph node or mediastinal mass biopsies of patients previously diagnosed as having CNSHL, in order to attempt to identify criteria as prognostic factors. Thirty-eight patients were selected. A total of 55.2 percent were male with a M:F ratio of 1.23:1 and a mean age of 29.3 years. 52.6 percent were in clinical stage I-II and 68.4 percent had symptoms B. Thirty-eight biopsy specimens were analysed and 57.9 percent were nodular sclerosis II. Immuno­phenotyping showed 100 percent positivity for CD30 and 68.4 percent for CD15. The FDC were identified by fascin, using the peroxidase-antiperoxidase streptavidin-avidin-biotin indirect immuno­enzimatic technique, which was performed on pre-treated slides with the biopsy specimens embedded in paraffin blocks. Fascin was considered to be the gold-standard. The CDF1 pattern was present in 7.9 percent, CDF2 in 47.4 percent and CDF3 in 44.7 percent. There was no association between the presence of the FDC and gender, age, clinical stage, response to treatment, but a tendency for association (p=0.056) between the subtypes of CNSHL. Patients with FDC present in their biopsies were followed up for a longer period of time - about 32.9 months. This enabled a significant statistical association (p=0.001) between the presence of FDC and length of follow-up.

Rastreamento familiar do fator V de Leiden: a importância da deteccão de portadores heterozigotos / Familiar tracking of factor V Leiden: the importance of detection in heterozygous carriers

O fator de Leiden é uma mutacão genética que predispõe seus portadores ao tromboembolismo venoso. O objetivo do estudo foi investigar a distribuicão dos alelos em 21 membros da família de três pacientes portadores de trombose com a presenca da mutacão do fator V de Leiden. A deteccão da mutacão no gene do fator V foi realizada entre portadores da mutacão no estado heterozigoto. Este estudo foi realizado no Centro de Hematologia e Hemoterapia do Ceará - Hemoce. Observou-se a presenca da mutacão no estado heterozigoto na família 1 (83,3 por cento), na família 2 (40 por cento) e na família 3 (50 por cento). No total de 24 membros (pacientes e familiares) analisados, 50 por cento (12/24) apresentaram a mutacão, todos no estado heterozigoto, 66,7 por cento (8/12) não apresentaram trombose. A deteccão do fator V de Leiden em pacientes portadores de eventos trombóticos é recomendado para esclarecimento das causas e para efetuar o rastreamento em membros de sua família, ainda sem o aparecimento de eventos trombóticos, de forma a avaliar os riscos associados e assim determinar um acompanhamento médico preventivo.

Avaliação das subclasses IgG1 e IgG3 na doença hemolítica perinatal / Assessment of IgG1 and IgG3 subclasses in perinatal hemolytic disease

A doença hemolítica perinatal (DHPN) ainda é um problema clínico. Nenhum teste isolado prediz, com segurança, a gravidade do quadro hemolítico. O objetivo do presente estudo foi determinar as subclasses de anticorpos IgG1 e IgG3 por citometria de fluxo no soro de 42 gestantes isoimunizadas e correlacionar os dados obtidos com a gravidade da DHPN. A distribuição dos fetos ou neonatos segundo a gravidade do quadro hemolítico evidenciou 13 casos com doença leve, 16 casos com doença moderada e 13 com doença grave. As subclasses foram detectadas em 33/42 (79 por cento) amostras. A subclasse IgG1, isoladamente, foi evidenciada em 14/33 (42,4 por cento) casos. Na relação entre gravidade da doença e subclasses de IgG, observou-se que IgG1 isolada foi encontrada em todos os grupos, e os valores da mediana de intensidade de fluorescência (MIF) foram significativamente mais altos nas formas mais graves da DHPN (p<0,01). Contrariamente, os valores da MIF para IgG3 se apresentaram mais homogêneos em todas as categorias (p=0,11). A presença de IgG3 parece, portanto, estar mais associada à hemólise leve. A associação das subclasses IgG1 e IgG3 está relacionada à situação clínica mais grave, o que se deve, possivelmente, à presença de IgG1 associada. Apesar dos altos valores para IgG1 e a associação de IgG1 com IgG3 indicarem maior gravidade da DHPN, sugere-se que outras variáveis sejam analisadas conjuntamente, uma vez que os relatos existentes na literatura, até o momento, não dão suporte para seu uso como instrumento exclusivo de avaliação de gravidade e prognóstico da doença.

The hemolytic disease of the newborn (HDN) continuesto be a clinical problem in spite of prophylaxis. Todate, none of the available tests, developed to predictthe severity of HDN, has provided complete reliability.The objective of the present study was to determinethe IgG1 and IgG3 subclasses in 42 isoimmunizedpregnant women, and to correlate them with clinicalseverity of hemolytic disease. The IgG subclasses weredetermined employing flow cytometry. According tothe clinical severity of HDN, fetuses and newbornbabies were classified as 13 mild, 16 moderate and 13severe cases. The IgG subclasses were detected in 33 ofthe 42 pregnant women. Of these, IgG1 waspredominant in 72.7% of the cases; either isolated(42.4%) or in association with IgG3 (30.3%). IgG1 waspresent in all the three clinical severity categories,however, its values were significantly higher in caseswith greater clinical severity of HDN (p<0.01). On theother hand, the distribution of IgG3 values within eachgroup was not statistically significant (p=0.11). IgG3seems to be more associated with the mild hemolyticform of the disease, whereas the association of IgG1and IgG3 suggested a clinically more severe form ofHDN. It is possible, however, that the severity in thesecases is related to the presence of IgG1. These resultssuggest that IgG1 and IgG3 isotypes should be includedin multi-parametric protocols for the evaluation ofclinical severity of HDN, as International literaturedoes not give support to the use of IgG subclassdetermination alone as a reliable indicator to predictseverity or prognosis of the disease.

Nódulos linfóides medulares / Bone marrow lymphoid nodules

A biópsia de medula óssea é parte integrante do estadiamento e seguimento de pacientes com doenças hematológicas. Nódulos linfóides são um achado comum, usualmente observados em associação com doenças inflamatórias crônicas, infecção, hemólise, síndromes mieloproliferativas e doenças auto-imunes. São, em geral, considerados reacionais. Sendo a medula óssea o sítio extranodal mais comumente envolvido nos linfomas foliculares, o diagnóstico diferencial mais importante é a infiltração medular por doença linfoproliferativa. Do ponto de vista prático, os infiltrados linfóides são, em geral, facilmente distinguíveis ao estudo histológico. Agregados reacionais são pequenos, têm bordas delimitadas, são compostos por uma população celular heterogênea e têm localização central. Nódulos malignos infiltram a medula óssea na região paratrabecular e são compostos por células clivadas. A análise imunofenotípica, utilizando um painel de anticorpos monoclonais, é capaz de definir a linhagem celular, subpopulação e estágio de diferenciação da população neoplásica, contribuindo para a confirmação do diagnóstico. Nos casos controversos, a análise molecular da proliferação linfóide pode ser útil. A monoclonalidade pode ser demonstrada pela restrição de cadeias leves ou através do rearranjo do DNA da cadeia pesada das imunoglobulinas. Idealmente, os resultados da análise molecular devem ser interpretados em conjunto com a análise morfológica e imunofenotípica. A morfologia continua sendo o padrão-ouro na avaliação da infiltração medular por linfoma folicular e as análises imunofenotípica e molecular devem ser consideradas complementares

Soroprevalência e perfil imunofenotípico de células linfóides T em indivíduos soropositivos para o vírus linfotrópico de células T humanas / Seroprevalence and immunophenotypic profile of T lymphocyte cells in human T lymphotropic virus seropositive individuals

O vírus linfotrópico de células T humana (HTLV) é transmitido por transfusões, uso compartilhado de agulhas contaminadas, aleitamento e contato sexual. A prevalência varia de acordo com a região geográfica, grupo racial e população estudada. Cerca de 1 por cento a 4 por cento dos indivíduos infectados desenvolvem algum tipo de doença em decorrência da infecção. É reconhecida a associação entre o HTLV-I e leucemia de células T do adulto e paraparesia espástica tropical (PET). Embora a maioria dos portadores permaneça assintomática, existem evidências de comprometimento funcional da resposta imune celular. Os objetivos desse trabalho foram avaliar a prevalência de soropositividade para HTLV-I/II na população de doadores de sangue do HEMOCE e analisar o perfil imunofenotípico de células linfóides circulantes em 26 doadores soronegativos, 11 soropositivos para HTLV-I sintomáticos e 24 assintomáticos, comparando-os entre si. A prevalência da soropositividade para HTLV-I/II foi de 0,66 por cento. No grupo de indivíduos contaminados pelo HTLV-I houve predomínio do sexo feminino e a maior média de idade. O grupo soropositivo apresentou menor valor de hemoglobina e o grupo sintomático evidenciou contagem de neutrófilos significativamente mais elevada. A contagem média de linfócitos não diferiu entre os grupos. A análise imunofenotípica mostrou que os valores médios de células CD3+, CD4+, CD8+ e relação CD4/CD8 não diferiram significativamente entre os grupos. Uma elevação de células CD8+ no grupo soropositivo foi observada embora não alcançasse significância estatística. A ativação de linfócitos CD8+ está envolvida na patogênese das doenças associadas ao HTLV-I. A definição do valor preditivo desse achado requer confirmação posterior

Human T lymphotropic virus (HTLV) can betransmitted by transfusions of cellular blood products,shared use of contaminated syringes, breast feedingand sexual intercourse. The prevalence of the infectionvaries according to geographic region, racial group,and population under risk. About 1% to 4% of theinfected individuals develop some form of infectionrelateddisease. The association of HTLV-I with AdultT-Cell Leukaemia, as well as the Tropical SpasticParaparesis, is presently well recognised. Although mostHTLV-I-infected individuals remain asymptomatic,there are indications that cellular immune responsesare functionally impaired. The aims of this study wereto determine the prevalence of HTLV-I/II seropositivityamong blood donors in HEMOCE and analyse theimmunophenotypic profile of peripheral lymphocytesin 26 HTLV-I seronegative blood donors, 11symptomatic and 24 asymptomatic HTLV-I seropositiveindividuals. The prevalence of HTLV-I/II was 0,66%. Inthe infected group a predominance of females wasobserved as well as a higher average age. The meanhemoglobin value was found to be significantly lowerin this group and the mean polymorphonuclearneutrophil count was significantly higher among thesymptomatic individuals. The mean lymphocyte andplatelet count were not significantly different betweenthe groups. Immuno-phenotyping evaluation revealedthat the mean CD3+, CD4+, CD8+ T cell counts, aswell as the CD4+/CD8+ ratio were not significantlydifferent between the groups. A slightly higher meanCD8+ T lymphocyte count was observed in theseropositive individuals, although it did not reachstatistical significance. The activation of CD8+ subsetis known to be part of pathogenesis of HTLV-I-relateddiseases. The predictive value of this immunologicalfinding needs further and long-range studies.

Bone marrow lymphoid aggregates in myelodysplastic syndromes: incidence, immunomorphological characteristics and correlation with clinical features and survival.

Lymphoid aggregates (LA) are a common finding in bone marrow biopsies but little is known about their clinical implications and biological significance. We found LA in 51/206 patients with myelodysplastic syndromes (MDS). There was no correlation with age, disease progression or overall survival. The group with LA had lower hemoglobin values (P=0.03), and was associated with an increase in reticulin fibres (P=0.01). Although they were more frequent in RAEB, this did not reach statistical significance. Most LA had a benign morphology and showed CD20 expression in three distinct patterns: central, perinodular or diffuse. No evidence of an association with lymphoproliferative disease was observed. LA probably represent an ongoing immune stimulation and are probably related to an altered bone marrow microenvironment, with no impact on prognosis.

Anormalidade nos cromossomos 12 e 18 / Abnormality of cromossomes 12 and 18 in patientes with myelodysplasic syndrome, previously diagnosed as chronic myeloid leukemia

Os autores apresentam um caso de Leucemia Mielomonocítica Crônica, inicialmente diagnosticado como Leucemia Mielóide Crônica, com alteraçöes nos cromossomos 12 e 18. O diagnóstico foi baseado no exame do sangue periférico, aspirado medular e cariótipo, além da exclusäo de condiçöes que, em geral, cursam com alteraçöes displásticas. Säo discutidas as dificuldades de diagnóstico diferencial com as condiçöes mieloproliferativas crönicas com cromossomo Filadélfia negativo e as alteraçöes cromossômicas encontradas.