Transfusion science最新文献

Centrifugal technology, continuous flow and discontinuous flow, has served as the technology platform for extracting cell concentrates of interest from peripheral blood (PB) for patient therapy for the past 35–40 yr. Models for procedure outcome exist for collection of normal donor (ND) platelet and granulocyte concentrates that integrate: (1) biological variables (pre-procedure PB cell concentration, the total circulating quantity of cells, donor/patient blood volume (BV)), (2) device efficiency, and (3) procedure parameters such as total blood processed (TBP), and in the case of cytoreductions – the volume collected. (cf. Hester J, Kellogg R, Mulzet A, et al., Blood (54) (1979) 254; Hester J, Ventura G, J Clin Apheresis (4) (1988) 188.) To date, no predictive CD34+ yield algorithm integrating these three variables has been formulated that could be applied prospectively for individual ND or patients (PT). There are economic, toxicity and statistical comparison benefits to be derived from generating such an algorithm.

A small pilot study is presented with a brief review of current publications that suggest the circulating quantity of CD34+ cells available to be collected and the quantity mobilized during leukapheresis are the major contributing factors to CD34+ yield, somewhat obscuring the role of the total blood processed (TBP). Intraprocedure CD34+ cell mobilization, incompletely characterized to date, appears to be a dynamic nonlinear process, as the harvested yield does not rise proportionally as the fraction of BV processed increases. And, like the pre-procedure PB CD34+ concentration and total circulating quantity, CD34+ mobilization during leukapheresis probably relates to prior treatment and the priming regimen. Studies that provide: (1) separate analyses of PT populations divided according to chemotherapy toxicity factors; (2) design and implementation of optimal priming regimens with respect to dose ‘intensity’ of both growth factors and chemotherapy; and (3) standardization of laboratory assays of CD34+ enumeration seem essential to generating a predictive algorithm.

For more than 30 yrs allogeneic hematopoietic stem cell transplantations have been successfully performed in patients with hematologic malignancies and bone marrow aplasia. Over the years the field of transplantation has changed dramatically. More and more unrelated donors became available, regimens for haploidentical transplantations were introduced and G-CSF mobilized peripheral blood stem cells and fetal cells from umbilical cord became available as alternate sources of hematopoietic stem cells. However, especially the introduction of donor lymphocyte infusions (DLI) for the successful treatment of leukemic relapses after allogeneic stem cell transplantations improved our understanding of transplantation immunology and opened amazing perspectives in allogeneic transplantation. It was long believed, that myeloablative therapy with high-dose chemotherapy and total body irradiation (TBI) are the sole antileukemic principles in allogeneic transplantations. But by now it became clear, that donor lymphocytes exert a very potent antileukemic effect, now referred as the graft-versus-leukemia (GVL) or graft-versus-malignancy (GVM) reaction. The efficacy of DLI in controlling leukemic relapses suggests that myeloablative therapy is not essential for long-term disease control. By exploiting the GVL or GVM reaction more intensively the role of chemotherapy and TBI is changing to immunosuppression. Sufficient immunosuppression to allow grafting, however, can be achieved with much lower doses as those which have been used in conventional transplants. Therefore allogeneic transplants have become also available for the elderly or for patients with concurrent medical conditions, which would have excluded them from conventional transplants. Moreover, this allogeneic transplantation strategy with reduced intensity conditioning is now also under investigation in patients with susceptible solid tumors and autoimmune diseases. However, one major obstacle in allogeneic transplantations, namely the graft-versus-host disease (GVHD), remains to be solved.

The aim of this retrospective study was to determine whether variations in the enumerated white cell contamination of leucocyte-depleted products was caused by the filter batch, the processing centre or by counting technology related issues. The influence of donor variation is also considered. The results suggest that for some red cell processes, variation is mainly the result of counting technology differences. Other products do not display similar trends though all leucodepletion processes may give rare high white count failures due to donor related issues, though defective filter batch cannot be excluded requiring continual review.

Objective. We analysed peripheral blood progenitor cell (PBPC) mobilisation and collection in order to assess the main factors related to CD34⁺ cell yields in patients affected by haematological malignancies.

Patients and Methods. The features of CD34⁺ cell mobilisation of patients with haematological malignancies that underwent autologous bone marrow transplantation were examined. Mobilisation chemotherapy consisted mainly of cyclophosphamide (CY) 4 or 7 g/m² followed by growth factors. Leukapheresis was started when the WBC counts reached 1.0 × 10⁹/l with the aim to collect at least 5 × 10⁶ CD34⁺ cells/kg body weight. The aphereses were performed on continuous-flow blood cell separators. The analysed variables were: age, diagnosis, CT mobilisation regimen, type of growth factor, number of previous CT lines, prior radiotherapy, days for WBC recovery and number of aphereses procedures to achieve the target of CD34⁺ cells.

Results. There were 41 consecutive patients (26 M/15 F): 21 non-Hodgkin’s lymphoma (NHL), 15 Hodgkin’s disease (HD), two chronic myeloid leukaemia (CML) and three multiple myeloma (MM). Eleven patients could not collect the proposed threshold of CD34⁺ cells. CY 4 mobilised patients recovered WBC counts in less days (P=0.03). By ANOVA, the days to WBC recovery had a linear function of the predictors “number of aphereses” and “type of mobilisation CT” (coefficients: 0.86 and 0.95, respectively). For the number of aphereses and WBC recovery after CT mobilisation, we obtained a correlation coefficient of 0.36 (P=0.02).

Conclusion. This study shows that it is feasible to mobilise and collect PBPC in patients previously treated with CT with or without RT. There was a linear correlation between the days for WBC recovery and the number of aphereses needed to collect the target number of CD34⁺ cells. The study suggests that early WBC recovery, using mainly CY 4 mobilisation chemotherapy, is an important predictor of a low number of aphereses to achieve a good CD34⁺ yield.

Background: Although several etiologies can be identified in thrombotic thrombocytopenic purpura (TTP), idiopathic cases are still frequent. Incomplete forms are more rare. Currently, the diagnosis may be made in cases of thrombocytopenia and microangiopathic hemolytic anemia. According to the literature, mortality and morbidity are significantly improved with plasma exchange. However, treatment in refractory forms remains problematic.

Case Report: A 33-year old woman presented with an incomplete form of TTP, refractory to a combination of therapeutics. The patient underwent plasma infusion, plasma exchange, and then was started on corticosteroids. She also received intravenous immunoglobulins and antiplatelet agents in close proximity to vincristine (Oncovin®) infusion. The main biological indicators used were the platelet count, hematocrit, LDH, and the presence of schistocytes. Following vincristine treatment, the patient’s condition rapidly improved.

Conclusion: Vincristine administered after the failure of standard therapeutics was effective in this refractory form of TTP.

There is no report in which three episodes of delayed hemolytic transfusion reaction (DHTR) occurred from multiple antibodies to red cells (RBCs) in the course of treatment of a patient. This paper describes episodes of anemia and hyperbilirubinemia in concert with the development of three alloantibodies in a multiple transfused patient. The patient was a 71-year-old male suffering from valvular heart disease and hemophilia B with a history of transfusions. Although he received compatible RBCs from 14 donors as judged by a crossmatch test using the albumin–antiglobulin method, three episodes of DHTR occurred after surgery. The first hemolytic episode on day 7 after surgery was due to anti-Di^a because of clinical and laboratory evidence which included jaundice, sudden increases in total bilirubin (T-Bil) and lactate dehydrogenase (LD) levels, and a decrease (2.2 g/dl) in hemoglobin (Hb) level. The second hemolytic episode on day 16 resulted from newly producted anti-Jk^b. The patient experienced fever, fatigue, nausea and anorexia, and laboratory data showed a second increase in T-Bil, a second decrease (3 g/dl) in Hb, and moderate elevations of blood urea nitrogen (BUN) and creatinine (CRE) levels. The third hemolytic episode on day 39 was due to anti-E. The patient complained of fever and fatigue and had a third unexplained drop (1.5 g/dl) in Hb despite no bleeding. This is the first reported case in which three episodes of DHTR occurred from different red cell antibodies.