RESUMO
BACKGROUND: RHD alleles leading to a reduced expression of D antigen of the red blood cell (RBC) surface may be erroneously typed as D- by serology and may cause anti-D immunizations when transfused to recipients. METHODS: To determine the occurrence of such alleles among apparent D- blood donors, molecular typing was implemented as a routine test using a pool of DNA. A total of 2,450 pretyped D- samples were tested in pools of 10 for the RHD-specific polymorphism in intron 4 and exon 7. Samples in polymer chain reaction (PCR) positive pools were individually reevaluated by exon-specific PCRs, sequencing, and serologic methods. RESULTS: Among 2,450 serologically D- blood donor samples tested, 101 (4.1%) carried the RHD gene. Nonfunctional RHD (RHDψ, RHD*CE(2-9)-D, and RHD*CE(3-7)-D), different weak D alleles such as RHD*weak D type 1, RHD*weak D type 4.3, RHD*weak D type 5, RHD*weak D type 38, and RHD*DEL were identified. CONCLUSION: We employed a PCR-based assay for RHD as a routine test using pools of ten DNA blood donor samples. The integration of RHD genotyping into the routine screening program using pools of DNA samples was straightforward. As a consequence, 19 (0.8%) blood donors carrying a weak D and Del phenotypes with the potential of causing anti-D immunizations in recipients were reclassified as D+. For each population, it would be necessary to adapt the RHD genotyping strategy to the spectrum of prevalent alleles.
Assuntos
Alelos , Doadores de Sangue , DNA/genética , Testes Diagnósticos de Rotina/métodos , Tipagem Molecular/métodos , Sistema do Grupo Sanguíneo Rh-Hr/genética , Brasil , Seguimentos , Humanos , Polimorfismo GenéticoRESUMO
The development of RBC autoantibodies resulting from or associated with allogeneic blood transfusions is not an easily determined complication of RBC transfusions. This report discusses one patient who developed RBC autoantibodies in association with an allogeneic blood transfusion and alloimmunization leading to a temporary bystander immune hemolysis. A 72-year-old woman was hospitalized as a result of severe anemia and received two units of ABO- and D-compatible RBCs. She had a history of two pregnancies 40 years before, but no history of RBC transfusion, and her antibody screen was negative. On the tenth day after transfusion her hemoglobin dropped, and alloanti-c was identified in her serum and eluate. At this time she received another two units of compatible blood according to her phenotype (group O, R1R1, K:-1). After 48 hours, she developed joint pain, pyrexia, and hemoglobinuria, and her Hb dropped from 9.2 g/dL to 5.3 g/ dL. The direct antiglobulin test was positive, an IgG autoantibody was present in the eluate, and the antibody investigation revealed the presence of anti-Jk(b) in addition to the previously identified alloanti-c. Her genotype was determined, and, based on the findings, two additional units were selected, found to be compatible, and transfused without incident. Transfusions were discontinued, and she was treated with IVIG and corticosteroids. Her Hb increased to 9.7 g/dL, and the patient made an uneventful recovery. It was concluded that transfusion of incompatible RBCs induced the formation of an autoantibody in this patient, resulting in lysis of bystander RBCs. The need for additional blood transfusion was successfully avoided by treatment with IVIG, steroid therapy, and rituximab.
Assuntos
Autoanticorpos/biossíntese , Antígenos de Grupos Sanguíneos/imunologia , Incompatibilidade de Grupos Sanguíneos/imunologia , Eritrócitos/imunologia , Hemólise/imunologia , Reação Transfusional , Idoso , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Murinos , Antígenos de Grupos Sanguíneos/genética , Incompatibilidade de Grupos Sanguíneos/complicações , Feminino , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , RituximabRESUMO
A possibilidade de realizar tipagem de grupos sangüíneos por DNA pode facilitar a resolução de problemasclínicos que não são solucionados pela hemaglutinação, aumentando assim a segurança dos pacientes transfundidos. Agenotipagem de grupos sangüíneos pode ser aplicada nas seguintes situações (a) tipagem de antígenos para os quais não há disponibilidade de anti-soros comerciais, (b) tipagem de pacientesrecentemente transfundidos e/ou que apresentam teste direto da antiglobulina positivo, (c) identificação de fetos de risco de mães RhD-negativo, (d) tipagem de doadores para aumentar o estoque de sangue raro para as transfusões. O objetivo desta revisão é apresentar as aplicações da genotipagem de grupos sangüíneos na medicina transfusional e materno-fetal e discutir os problemas clínicos que potencialmente podem ser resolvidospelas técnicas moleculares. A base de dados utilizada nesta revisão foi a busca no MEDLINE e por meio de revisão das referências bibliográficas. Todos os trabalhos e revisões incluídos abrangeram a segurança transfusional e materno-fetal, as bases moleculares dos antígenos de grupos sangüíneos e as aplicações da genotipagem na práticaclínica. Os dados foram coletados através da avaliação dos resultados de estudos e revisões de polimorfismosde grupos sangüíneos e suas aplicações na clínica.
Assuntos
Antígenos de Grupos Sanguíneos , Tipagem e Reações Cruzadas Sanguíneas , Transfusão de Sangue , Eritroblastose Fetal , Genótipo , HemaglutinaçãoRESUMO
Chylomicrons are the lipoproteins that transport dietary lipids in the blood. Although neoplastic diseases are often accompanied by alterations in lipid metabolism, chylomicrons are scarcely explored in cancer, despite their importance for the body's energy supply. Moreover, no data are available regarding chylomicron metabolism in chronic lymphocytic leukemia (CLL). Chylomicron metabolism in the bloodstream consists of lipolysis by lipoprotein lipase and uptake of remnants by the liver and is difficult to assess in the human body. Among the methods to evaluate this pathway, the determination of the plasma kinetics of triglyceride-rich emulsions that mimic chylomicrons is a practical and straightforward approach. A double-labeled chylomicron-resembling emulsion was injected into 10 patients with CLL and into 11 normolipidemic healthy subjects. The plasma kinetic curves of the emulsion 3H-triglyceride and 14Ccholesteryl ester were determined in plasma samples collected over 30 min. The fractional clearance rate (FCR) of triglycerides in CLL was not changed compared with controls. The FCR of cholesteryl esters was also no different from controls. These results indicate that chylomicron lipolysis and remnant removal are not affected in CLL.
Assuntos
Quilomícrons/sangue , Emulsões/metabolismo , Leucemia Linfocítica Crônica de Células B/sangue , Idoso , Idoso de 80 Anos ou mais , Radioisótopos de Carbono , Ésteres do Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Quilomícrons/administração & dosagem , Feminino , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Trioleína/análise , TrítioRESUMO
A infusao de células hematopoéticas totipotentes criopreservadas permite a recuperaçao da hematopoese após quimioterapia mieolblativa. Objetivo. A formaçao de cristais de gelo durante o processo de congelamento é o fator principal que causa ruptura das estruturas celulares. A criopreservaçao dessas células a uma taxa constante preveniria os danos causados pelo congelamento brusco. Métodos. Vinte e três pacientes com mediana de 25 anos (variaçao 3-57) tiveram a medula óssea e/ou células-tronco periféricas (CTP) coletadas no período de março de 1993 a outubro de 1994, totalizando 86 congelamentos. Os pacientes apresentavam as seguintes neoplasias: linfoma nao-Hodgkin (n=5), leucemia mielóide aguda (n=8), leucemia linfóide aguda (n=6), doença de Hodkin (n=3) e mieloma múltiplo (n=1). O congelamento foicontrolado por um computador, acoplado ao sistema, às seguintes temperaturas: -1 graus Celsius/min até -45 graus Celsius e depois a -10 graus Celsius/min até -80 graus Celsius. Após o congelamento, as células foram mantidas em freezer a -110 graus Celsius até o momento da infusao. Para obtençao das CTP, empregou-se o fator de crescimento estimulante de granulócitos (G-CSF). Resultados. Uma mediana de 3,16 x 10(8) céls./kg (variaçao 0,86-24,22) de CTP e 2,03 x 10(8) céls./kg (variaçao 0,19-12,21) de medula óssea foi congelada. A mediana para atingir granulócitos maior ou igual a 500/muL e plaquetas maior que 20.000/muL foi de 12 dias (variaçao 8-40) e 31 dias (variaçao 8-80), respectivamente. Todos os pacientes tiveram recuperaçao hematopoética após a infusao das células criopreservadas. Conclusao. A criopreservaçao em congelador program vel permite o armazenamento de células hematopoéticas e, potencialmente, pode causar menor dano celular.
Assuntos
Feminino , Humanos , Pré-Escolar , Pessoa de Meia-Idade , Adulto , Adolescente , Criança , Células-Tronco , Medula Óssea , Criopreservação/métodos , Transplante Autólogo/métodos , Congelamento , Hematopoese , Neoplasias/tratamento farmacológico , Antineoplásicos/uso terapêuticoRESUMO
UNLABELLED: The cryopreservation of hematopoietic stem cells can be used for rescuing the hematopoiesis after high dose chemotherapy. PURPOSE: The ice crystal formation during the freezing procedure is the key point that can be harmful to the cells. The cryopreservation of hematopoietic stem cells in a controlled-rate freezer could decrease the cell damage. METHODS: Twenty-three patients with a median age of 26 years (range 03-57) had bone marrow and/or peripheral blood stem cells harvested from March 1993 through October 1994, ending up to 86 freezing procedures. The patient's diagnoses are as follows: Non-Hodgkin's Lymphoma (n = 5); Acute Myelogenous Leukemia (n = 8); Acute Lymphocytic Leukemia (n = 6); Hodgkin's disease (n = 3); Multiple Myeloma (n = 1). The cells were frozen away in a controlled-rate freezer chamber at the following rate: -1 degree C/min from room temperature to -45 degrees C and then, at -10 degrees C/min down to -80 degrees C. After freezing, the cells were kept into mechanical freezers until the marrow infusion. To mobilize PBSC (peripheral blood stem cells), G-CSF (granulocyte colony stimulating factor) was given. RESULTS: A median of 3.16 x 10(8) cells/kg (range 0.86-24.22) of PBSC and 2.03 x 10(8) cells/kg (0.19-12.21) of bone marrow cells were frozen. The median time to reach granulocytes greater than 500/microL and platelets greater than 20,000/microL was 12 days (range 8-40) and 31 days (range 8-80), respectively. All patients had marrow engraftment after infusion of hematopoietic stem cells. CONCLUSION: The cryopreservation procedure using a controlled-rate freezer can store hematopoietic stem cells and potentially, cause less damage to the cells.