Comparative analysis between cytomorphology and flow cytometry methods in central nervous system infiltration assessment in oncohematological patients

ABSTRACT Introduction Oncohematological patients require the evaluation for possible infiltration of the central nervous system (CNS) by neoplastic cells at diagnosis and/or during the monitoring of the chemotherapeutic treatment. Morphological analysis using conventional microscopy is considered the method of choice to evaluate the cerebrospinal fluid (CSF) samples, despite technical limitations. Objective This study aimed to compare the performance of the cytomorphology and flow cytometric immunophenotyping (FC) in the detection of CNS infiltration. Method We evaluated 520 CSF samples collected from 287 oncohematological patients for whom the detection of neoplastic cells was simultaneously requested by cytomorphology and FC. Results Laboratory analyses revealed 435/520 (83.7%) conclusive results by the two methods evaluated, among which 385 (88.5%) were concordant. Discordance between the methods was observed in 50/435 (11.5%) samples, 45 (90%) being positive by FC. Furthermore, the FC defined the results in 69/72 (95.8%) inconclusive samples by cytomorphology. The positivity of FC was particularly higher among hypocellular samples. Among 431 samples with a cell count of < 5/μL, the FC identified neoplastic cells in 75 (17.4%), while the cytomorphology reported positive results in 26 (6%). Among the samples that presented adequate cell recovery for evaluation by both methods (506/520), the comparative analysis between FC and cytomorphology revealed a Kappa coefficient of 0.45 (CI: 0.37-0.52), interpreted as a moderate agreement. Conclusion The data showed that the CSF analysis by FC helps in the definition of CNS infiltration by neoplastic cells, particularly in the cases with dubious morphological analysis or in the evaluation of samples with low cellularity.

30 Years of Experience with Non-Hodgkin Lymphoma in Children and Adolescents: a retrospective cohort study

SUMMARY OBJECTIVE Describe the clinical and demographic characteristics of pediatric patients with non-Hodgkin's lymphoma (NHL) enrolled in a tertiary unit of Pediatric Hematology between 1982-2015. PATIENTS AND METHODS A retrospective cohort study of 140 patients aged 16 years or less with NHL. Demographic characteristics, data on diagnosis, and outcomes were analyzed. The overall survival (OS) analysis and stratification by the most frequent histological subtypes were performed using the Kaplan-Meier method. RESULTS One hundred and thirty-six patients with de novo NHL and four with NHL as a second malignancy were analyzed. The median age at diagnosis was 6.4 years (interquartile range, 4.2 to 11.1 years); 101 patients were males. Four patients had primary immunodeficiency, four had human immunodeficiency virus, two post-liver transplantation, and one had autoimmune lymphoproliferative syndrome. The most frequent histological type was NHL of mature B- cell (B-NHL-B; 67.1%), with Burkitt's lymphoma being the most frequent subtype, and lymphoblastic lymphoma (LBL, 21.4%). The main clinical manifestation at the diagnosis was abdominal tumors (41.4%). During the follow-up time, 13 patients relapsed, but five of them reached a second remission. Thirty-five patients died, and 103 remained alive in clinical remission. No contact was possible for two patients. The OS at 5 years was 74.5% (± 3.8%). The OS estimated for patients with LBL, NHL-B, and the remaining was 80.4%±7.9%, 72.8%±4.7%, and 74.5%±11%, respectively (P = 0.58). CONCLUSION Our results are comparable with cohorts from other middle-income countries.

RESUMO OBJETIVO Descrever as características clínicas e demográficas de pacientes pediátricos com linfoma não Hodgkin (LNH) em uma unidade terciária de Hematologia Pediátrica entre 1982-2015. PACIENTES E MÉTODOS Estudo de coorte retrospectivo de dados de prontuários de 140 pacientes com idade até 16 anos com LNH. Características demográficas e dados relativos ao diagnóstico e evolução foram analisados. A sobrevida global (SG) e estratificada pelos subtipos histológicos mais frequentes foi analisada pelo método de Kaplan-Meier. RESULTADOS Dados de 136 pacientes com LNH de novo e quatro com LNH como segunda neoplasia foram analisados. A mediana de idade ao diagnóstico foi 6,4 anos (intervalo interquartil: 4,2 a 11,1 anos); 101 pacientes eram meninos. Onze pacientes apresentavam imunodeficiência (quatro primária, quatro secundária ao vírus da imunodeficiência humana adquirida, dois pós-transplante hepático e um com síndrome linfoproliferativa autoimune). Os tipos histológicos mais frequentes foram o LNH de células B madura (LNH-B, 67,1% dos pacientes), sendo o linfoma de Burkitt o subtipo mais frequente, e o linfoma linfoblástico (LL, 21,4%). A principal manifestação clínica ao diagnóstico foi massa abdominal (41,4%). A mediana de seguimento dos sobreviventes foi 7,7 anos (intervalo interquartil: 3,3 a 10,9 anos). Treze pacientes recidivaram (cinco alcançaram segunda remissão clínica), 35 faleceram, 103 permanecem vivos em remissão completa e dois perderam o seguimento. A probabilidade de SG em cinco anos foi 74,5%±3,8%. Para os pacientes com LL, LNH-B e os demais, a SG foi 80,4%±7,9%, 72,8%±4,7% e 74,5%±11%, respectivamente (P=0,58). CONCLUSÃO Nossos resultados são comparáveis aos de outros países de renda média.

Cytogenetic abnormalities, WHO classification, and evolution of children and adolescents with acute myeloid leukemia

ABSTRACT Objectives: To describe cytogenetic and molecular abnormalities observed in children and adolescents with acute myeloid leukemia (AML), classify AML according to the World Health Organization (WHO) classifications from 2008 and 2016, and evaluate the prognosis according to clinical characteristics and cytogenetic abnormalities. Methods: A retrospective longitudinal study was performed on a population of 98 patients with AML, aged up to 16 years, seen in a single hospital from 2004 to 2015. Results: Among the 80 patients for whom it was possible to analyze the karyotype, 78.7% had chromosomal changes, the most frequent being t(15;17)(q22;q21). Of the 86 patients for whom we had cytogenetic or molecular data, making it possible to classify their AML according to the WHO classification, 52.3% belonged to the group with recurrent genetic abnormalities, 22% to the "AML not otherwise specified" group, 18.6% to the group with myelodysplasia-related cytogenetic changes, and 7% to the group with Down syndrome-related leukemia. Five-year overall survival (OS) for the whole group was 49.7% ± 5.2%. In the univariate and multivariate analyses, patients with myelodysplasia-related cytogenetic changes (OS 28.1% ± 12.2%) and those with "AML not otherwise specified" (OS 36.1% ± 11.2%) had an unfavorable prognosis when compared to patients with AML with recurrent genetic abnormalities (OS 71% ± 5.8%) and patients with Down syndrome-related AML (OS 83% ± 15.2%, p = 0.011). Conclusions: The results corroborate the importance of cytogenetic abnormalities as a prognostic factor and indicate the need for cooperative and prospective studies to evaluate the applicability of the WHO classification in the pediatric population.

Hemophagocytic lymphohistiocytosis: a case series of a Brazilian institution

Objective: To describe the clinical and laboratory presentation of hemophagocytic lymphohistiocytosis in children treated at a referral institution. Methods: A retrospective descriptive study was carried out of seven children diagnosed with hemophagocytic lymphohistiocytosis between 2010 and 2012. The criteria for diagnosis were those proposed by the Histiocyte Society. When indicated, immunochemotherapy was prescribed according to the HLH94 and HLH2004 protocols of the Histiocyte Society. Results: The patients' ages at diagnosis ranged from one month to nine years. All patients had splenomegaly, fever, anemia, thrombocytopenia, hyperferritinemia and hypertriglyceridemia. Bone marrow hemophagocytosis was detected in six patients. In six cases, infectious diseases triggered the syndrome. In two cases, associated with visceral leishmaniasis, remission was achieved after treatment of the underlying infection. Three patients, who had Epstein–Barr-related hemophagocytic lymphohistiocytosis, required treatment with immunochemotherapy. They are alive and in remission; one patient had symptoms of juvenile rheumatoid arthritis and another, who was suspected of having primary hemophagocytic lymphohistiocytosis, entered into remission after bone marrow transplantation. Two deaths (28.6%) occurred in patients with suspected primary hemophagocytic lymphohistiocytosis; one whose clinical picture was triggered by cytomegalovirus infection did not respond to immunochemotherapy and the other died before any specific treatment was provided. Conclusion: As reported before, hemophagocytic lymphohistiocytosis has a multifaceted presentation with nonspecific signs and symptoms. In secondary forms, remission may be achieved by treating the underlying disease. In the primary forms, remission may be achieved with immunochemotherapy, but bone marrow transplantation is required for cure...

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...

Gene rearrangement study for minimal residual disease monitoring in children with acute lymphocytic leukemia

OBJECTIVE To detect markers for minimal residual disease monitoring based on conventional polymerase chain reaction for immunoglobulin, T-cell receptor rearrangements and the Sil-Tal1 deletion in patients with acute lymphocytic leukemia. METHODS Fifty-nine children with acute lymphocytic leukemia from three institutions in Minas Gerais, Brazil, were prospectively studied. Clonal rearrangements were detected by polymerase chain reaction followed by homo/heteroduplex clonality analysis in DNA samples from diagnostic bone marrow. Follow-up samples were collected on Days 14 and 28-35 of the induction phase. The Kaplan-Meier and multivariate Cox methods were used for survival analysis. RESULTS Immunoglobulin/T-cell receptor rearrangements were not detected in 5/55 children screened (9.0%). For precursor-B acute lymphocytic leukemia, the most frequent rearrangement was IgH (72.7%), then TCRG (61.4%), and TCRD and IgK (47.7%); for T-acute lymphocytic leukemia, TCRG (80.0%), and TCRD and Sil-Tal deletion (20.0%) were the most common. Minimal residual disease was detected in 35% of the cases on Day 14 and in 22.5% on Day 28-35. Minimal residual disease on Day 28-35, T-acute lymphocytic leukemia, and leukocyte count above 50 x 109/L at diagnosis were bad prognostic factors for leukemia-free survival in univariate analysis. Relapse risk for minimal residual disease positive relative to minimal residual disease negative children was 8.5 times higher (95% confidence interval: 1.02-70.7). CONCLUSION Immunoglobulin/T-cell receptor rearrangement frequencies were similar to those reported before. Minimal residual disease is an independent prognostic factor for leukemia-free survival, even when based on a non-quantitative technique, but longer follow-ups are needed.

Incidence and risk factors for central nervous system relapse in children and adolescents with acute lymphoblastic leukemia

BACKGROUND: Despite all the advances in the treatment of childhood acute lymphoblastic leukemia, central nervous system relapse remains an important obstacle to curing these patients. This study analyzed the incidence of central nervous system relapse and the risk factors for its occurrence in children and adolescents with acute lymphoblastic leukemia. METHODS: This study has a retrospective cohort design. The studied population comprised 199 children and adolescents with a diagnosis of acute lymphoblastic leukemia followed up at Hospital das Clinicas, Universidade Federal de Minas Gerais (HC-UFMG) between March 2001 and August 2009 and submitted to the Grupo Brasileiro de Tratamento de Leucemia da Infância - acute lymphoblastic leukemia (GBTLI-LLA-99) treatment protocol. RESULTS: The estimated probabilities of overall survival and event free survival at 5 years were 69.5% ( 3.6%) and 58.8% ( 4.0%), respectively. The cumulative incidence of central nervous system (isolated or combined) relapse was 11.0% at 8 years. The estimated rate of isolated central nervous system relapse at 8 years was 6.8%. In patients with a blood leukocyte count at diagnosis > 50 x 10(9)/L, the estimated rate of isolated or combined central nervous system relapse was higher than in the group with a count < 50 x 10(9)/L (p-value = 0.0008). There was no difference in cumulative central nervous system relapse (isolated or combined) for the other analyzed variables: immunophenotype, traumatic lumbar puncture, interval between diagnosis and first lumbar puncture and place where the procedure was performed. CONCLUSIONS: These results suggest that a leukocyte count > 50 x 10(9)/L at diagnosis seems to be a significant prognostic factor for a higher incidence of central nervous system relapse in childhood acute lymphoblastic leukemia.

Deficiência de ferro em lactentes brasileiros com doença falciforme / Iron deficiency in Brazilian infants with sickle cell disease

OBJETIVO: Avaliar a deficiência ou sobrecarga de ferro em lactentes com doença falciforme, a fim de embasar a decisão de recomendar (ou não) a suplementação profilática de ferro nessa população. MÉTODOS: Estudo retrospectivo transversal envolvendo 135 lactentes menores de 2 anos (66 meninos e 69 meninas), com genótipos SS e SC (77/58), nascidos entre 2005 e 2006 em Minas Gerais. Os indicadores de uma possível deficiência de ferro foram: volume corpuscular médio (VCM), hemoglobina corpuscular média (HCM), saturação da transferrina (ST) e ferritina. Dezessete lactentes [12,6 por cento, intervalo de confiança de 95 por cento (IC95 por cento) 7,0-18,2 por cento] haviam recebido hemotransfusão antes da coleta dos exames. RESULTADOS: ST e ferritina estavam significativamente mais baixas nos lactentes com hemoglobina SC (p < 0,001). Quando dois indicadores foram utilizados para definir a deficiência de ferro (VCM ou HCM baixos mais ST ou ferritina baixas), 17,8 por cento das crianças (IC95 por cento 11,3-24,3 por cento) tinham deficiência de ferro, predominando naquelas com perfil SC (p = 0,003). Análise das crianças que não haviam sido transfundidas (n = 118) mostrou prevalência de ferropenia em 19,5 por cento. Constatou-se aumento de ferritina em 15 lactentes (11,3 por cento; IC95 por cento 5,9-16,7 por cento); a maioria havia sido transfundida. CONCLUSÕES: A maior parte dos lactentes com doença falciforme não desenvolve deficiência de ferro, mas alguns têm déficit significativo. Este estudo indica que lactentes com doença falciforme, principalmente aqueles com hemoglobinopatia SC, talvez possam receber ferro profilático; no entanto, a suplementação deve ser suspensa após a primeira hemotransfusão.

OBJECTIVE: To assess iron deficiency or overload in infants with sickle cell disease in order to support the decision to recommend (or not) iron prophylactic supplementation in this population. METHODS: Cross-sectional and retrospective study with 135 infants below 2 years old (66 boys and 69 girls), 77 with SS and 58 with SC hemoglobin, born between 2005 and 2006 in Minas Gerais, Brazil. Indicators of possible iron deficiency were: mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), transferrin saturation (TS), and ferritin. Blood transfusions had been given to 17 infants (12.6 percent, 95 percent confidence interval [95 percentCI] 7.0-18.2 percent) before laboratory tests were done. RESULTS: Ferritin and TS were significantly lower in SC infants (p < 0.001). When two indices were considered for the definition of iron deficiency (low MCV or MCH plus low ferritin or TS), 17.8 percent of children (95 percentCI 11.3-24.3 percent) presented iron deficiency, mainly those with SC hemoglobin (p = 0.003). An analysis of infants who were not given transfusions (n = 118) showed that 19.5 percent presented iron deficiency. Fifteen infants (11.3 percent, 95 percentCI 5.9-16.7 percent) presented increased ferritin; the majority had been transfused. CONCLUSIONS: Most infants with sickle cell disease do not develop iron deficiency, though some have a significant deficit. This study indicates that infants with sickle cell disease, mainly those with SC hemoglobin, may receive prophylactic iron; however, supplementation should be withdrawn after the first blood transfusion.

Acute splenic sequestration in a cohort of children with sickle cell anemia / Sequestro esplênico agudo em coorte de crianças com anemia falciforme

OBJETIVO: Analisar o sequestro esplênico agudo (SEA) em crianças com anemia falciforme, provindas da triagem neonatal de Minas Gerais e acompanhadas pelo Hemominas de Belo Horizonte (MG). MÉTODOS: Coorte retrospectiva de 255 crianças com hemoglobinopatia SS/Sβº, nascidas entre 01/01/2000 e 31/12/2004 e acompanhadas até 31/12/2006. Os dados foram extraídos dos prontuários médicos. RESULTADOS: Oitenta e nove pacientes apresentaram 173 eventos de SEA (10,2 primeiros eventos por 100 pacientes/ano), sendo que 75% dos primeiros episódios de SEA ocorreram até 2 anos de vida. A probabilidade estimada de ocorrência do primeiro episódio de SEA foi de 40%. A recorrência atingiu 57,3%. Após o primeiro episódio de SEA, a esplenectomia foi indicada em apenas 12,4% dos casos; após o segundo, em 60,4% dos casos. Após o terceiro episódio, 41,7% dos casos ainda permaneceram sob observação clínica. A mediana do tempo entre indicação e realização da esplenectomia foi de 2 meses. Nesse intervalo, 37,2% das crianças tiveram novo episódio de SEA e uma delas faleceu. A letalidade no primeiro episódio foi de 1,1% e de 7,8% em episódios subsequentes. Entre as 255 crianças ocorreram 19 óbitos: 36,8% devido a infecções e 26,3% após SEA. CONCLUSÕES: O SEA é um evento comum na anemia falciforme, principalmente nos 2 primeiros anos de vida, com recidiva em mais da metade dos casos. Predominou conduta conservadora na indicação da esplenectomia. Embora a letalidade tenha sido baixa, o SEA representou a segunda causa de óbito. Isso aponta para fragilidades estruturais do sistema de saúde de MG e para a necessidade de melhor capacitação profissional na abordagem do problema.

OBJECTIVE: To analyze acute splenic sequestration (ASS) in children with sickle cell anemia diagnosed through a newborn screening program in the state of Minas Gerais, Brazil, and followed up at the hematology center in the city of Belo Horizonte, Minas Gerais, Brazil. METHODS: Retrospective cohort of 255 children with sickle cell anemia (Hb SS/Sβº) born between January 01, 2000, and December 31, 2004, and followed up until December 31, 2006. Data were abstracted from the patients' medical records. RESULTS: A total of 89 patients had 173 episodes of ASS (10.2 first episodes per 100 patient-years); 75% of the first episodes occurred before 2 years of age. The estimated probability of occurrence of the first episode of ASS during the study period was 40%. Recurrence rate reached 57.3%. After the first episode, splenectomy was indicated in only 12.4% of the cases; after the second, in 60.4% of the cases. After the third episode, 41.7% of the patients remained under clinical observation. The median time between indication for splenectomy and the actual surgical procedure was 2 months. During the intervening period, 37.2% of the children suffered a new episode of ASS and one child died. Case-fatality rate was 1.1% for the first episode and 7.8% for the subsequent episodes. Among a total of 255 children, 19 died: 36.8% due to infections and 26.3% after ASS. CONCLUSIONS: ASS is relatively common in sickle cell anemia, mainly in the first 2 years of life; relapse occurs in more than half of the cases. Conservative management instead of immediate splenectomy was the method of choice. Although the case-fatality rate was low, ASS was the second most common cause of death. These results disclose some fragilities of the health system in the state of Minas Gerais and the need for better professional education to approach ASS crises.

Diagnóstico laboratorial da doença falciforme em neonatos e após o sexto mês de vida / Laboratorial diagnosis of sickle cell disease in the neonate and after the sixth month of life

A doença falciforme é uma desordem genética da hemoglobina, com alta prevalência no Brasil. Apresenta elevada morbidade e mortalidade, necessitando de identificação e tratamento precoces. O reconhecimento disso tornou o seu diagnóstico obrigatório pelos testes de triagem neonatal, em todo o país. O diagnóstico laboratorial da doença no neonato baseia-se na detecção da hemoglobina S utilizando-se preferencialmente as técnicas de IEF e/ou HPLC que apresentam elevada sensibilidade e especificidade. Estes métodos permitem também a detecção dos portadores de traço e de outras hemoglobinas variantes. Na doença falciforme as principais possibilidades fenotípicas ao nascimento são: Hb FS, Hb FSC, Hb FSA e Hb FSD-Punjab. Qualquer que seja o fenótipo encontrado para a doença a criança deverá ser encaminhada à consulta médica e o exame repetido após o sexto mês de vida para confirmação do perfil hemoglobínico. Outros exames complementares podem ser necessários para o diagnóstico diferencial das diferentes formas da doença tais como a dosagem de Hb A2 e Hb Fetal como também a realização do estudo familiar.

Sickle Cell disease (SCD) is a genetic disorder of the hemoglobin, with high prevalence in Brazil. It presents high morbidity and mortality with early identification and treatment being necessary. The recognition of this situation has made the diagnosis of SCD mandatory through neonatal screening in Brazil. SCD Laboratorial diagnosis in the neonate is based on the detection of S hemoglobin, in preference, using IEF and/or HPLC techniques, which present high sensitivity and specificity. These methods also allow the detection of carriers traits and other variant hemoglobins. The main phenotypic possibilities on SCD at birth are: Hb FS, Hb FSC, Hb FSA and Hb FSD-Punjab. The child should be referred for medical assessment independent of the phenotype found and the examination being repeated after six months of life to confirm of the hemoglobinic profile. Other complementary examinations may be necessary for differential diagnoses of the different forms of the disease, such as the measurement of Hb A2 and Fetal Hb, as well as a study of the family history.

Traço falciforme: heterozigose para hemoglobina S / Sickle cell trait: heterozygous for the hemoglobin S

A hemoglobina S (HbS) é uma das alterações hematológicas hereditárias de maior freqüência. No Brasil, a prevalência do traço falciforme (HbAS) varia de 2 por cento a 8 por cento. Com esta freqüência gênica, estima-se, no Brasil, a existência de mais de dois milhões de portadores do traço falciforme. Diferentemente dos portadores em homozigose para a Hb S (Hb SS), os indivíduos com traço falciforme não apresentam sintomas vaso-oclusivos sob condições fisiológicas. Alguns sinais clínicos associados ao traço falciforme somente ocorrem sob condições que propiciam o processo de falcização, como hipóxia, acidose e desidratação. A expectativa de vida é semelhante ao do resto da população. Assim, a condição de portador assintomático não deve ter nenhum impacto no estilo e qualidade de vida.

Hemoglobin S (HbS) is one of the most common hereditary hematological alterations. In Brazil, the frequency of the sickle cell trait (HbAS) varies from 2 percent to 8 percent. Thus, there is an estimate of more than two million carriers of the HbAS sickle cell trait in Brazil. Different to homozygous carriers for Hb S (Hb SS), individuals with the sickle cell trait do not present with vaso-occlusive symptoms under physiologic conditions. Some clinical signals associated to the sickle cell trait only occur under conditions that favor the sickling process, including hypoxia, acidosis and dehydration. Life expectancy is similar to the general population. Hence, the condition of asymptomatic carrier should not affect the style and quality of life.

Anemia hemolítica auto-imune como sintoma inicial de linfoma de hodgkin / Autoimmune hemolytic anemia as an initial symptom in Hodgkin's disease

Objetivo: relatar um caso de linfoma de Hodgkin precedido por anemia hemolítica auto-imune (AHAI). Descrição: relata-se o caso de um paciente de 10 anos de idade com quadro clínico e laboratorial típico de AHAI por anticorpo de reação fria. Após quatro anos de evolução, com resposta inicial ao uso de corticóide e imunoglobulina, o paciente apresentou anemia refratária, hepatoesplenomegalia, febre e perda de peso, sendo diagnosticado linfoma de Hodgkin (LH) estádio IIB. Após 23 meses de encerramento da quimioterapia, o paciente encontra-se em remissão clínica, tanto da AHAI quanto do linfoma. Comentários: a AHAI consiste de um grupo de doenças cuja característica comum é a presença de auto-anticorpos que diminuem o tempo de sobre vida dos eritrócitos. A maioria dos casos de AHAI crônica é secundária a uma doença de base grave, assim, esses pacientes demandam seguimento clínico rigoroso e prolongado. O presente relato de caso mostra que o LH deve ser considerado no diagnóstico diferencial de uma criança com AHAI crônica.

Clinical course of autoimmune hemolytic anemia: an observational study

OBJECTIVE: Autoimmune hemolytic anemia is characterized by the production of autoantibodies against erythrocyte membrane antigens. This study was carried out to identify the clinical, immunological and outcome characteristics of autoimmune hemolytic anemia patients treated at the (HC-UFMG) Pediatric Hematology Unit and the Hemocentro de Belo Horizonte. METHODS: We evaluated 17 patients younger than 15 years old admitted from 1988 to 2003 were evaluated. Autoimmune hemolytic anemia diagnosis was based on the presence of acquired hemolysis and confirmed by positive direct Coombs polyspecific test results. Clinical, laboratory, and outcome data were obtained from patient records. RESULTS: The median age at diagnosis was 10.5 months. The direct Coombs polyspecific test was positive in 13 and negative in four patients. Monospecific testing was performed for 14 patients. The most frequent red cell autoantibody was IgG (five patients), followed by IgM in two. Thirteen patients had severe anemia and needed blood transfusions. Underlying diseases were identified in four patients: systemic lupus erythematosus, Hodgkin's lymphoma, autoimmune hepatitis and Langerhans cell histiocytosis. The remaining patients were classified as having primary disease. The median follow-up period was 11 months (5 to 23 months). Three children died, two after splenectomy and one with complications of the underlying disease. CONCLUSION: Autoimmune hemolytic anemia is rare in children and adolescents. Although patients usually respond to corticosteroids and/or immunoglobulin, fatal cases can occur. Prognosis is worse in patients with chronic underlying diseases.

Leucemia mielóide aguda na criança: experiência de 15 anos em uma única instituiçäo / Acute myeloid leukemia in childhood: fifteen-year experience in a single institution

OBJETIVO: Verificar a sobrevida de crianças com leucemia mielóide aguda antes e após a adoçäo de quimioterapia baseada no protocolo Berlim-Frankfurt-Munique-83. Analisar a influência prognóstica dos fatores idade, gênero, estado nutricional, leucometria inicial e introduçäo da droga etoposida na fase de induçäo da remissäo. MÉTODOS: Estudo prospectivo/retrospectivo com 83 crianças portadoras de leucemia mielóide aguda, diagnosticadas no Hospital das Clínicas da UFMG entre 1986 e 2000. Até 1990, 15 crianças foram tratadas com dois a três ciclos de citarabina e daunorrubicina, seguidos de esquemas variados de consolidaçäo/manutençäo; de janeiro de 1991 a novembro de 1992, 15 pacientes em estudo piloto utilizaram etoposida na fase de induçäo do protocolo alemäo; de dezembro de 1992 a junho de 1999, a etoposida foi utilizada aleatoriamente. RESULTADOS: O tempo mediano de seguimento foi de cinco anos. As taxas de remissäo iniciais foram de 40 por cento e 66 por cento, antes e após a adoçäo do protocolo alemäo (p = 0,11). O óbito durante a induçäo, causado por infecções e/ou hemorragia, foi a principal causa para näo se obter a remissäo. As probabilidades estimadas de sobrevida e de remissäo clínica completa aos cinco anos foram de 31 por cento±5,4 por cento e 49,7 por cento±7,4 por cento, respectivamente. Recidivas ocorreram em 22 casos, todas medulares. Crianças abaixo de seis anos de idade tiveram prognóstico significativamente pior. Gênero, leucometria inicial e estado nutricional näo influenciaram o prognóstico. Crianças que aleatoriamente utilizaram a etoposida tiveram a duraçäo da remissäo menor do que aquelas que näo a usaram. CONCLUSÕES: A utilizaçäo de terapia baseada no protocolo alemäo melhorou o prognóstico. A administraçäo da etoposida foi desfavorável, näo se encontrando explicaçäo plausível para tal observaçäo