Collection of mononuclear cells in the Spectra for the generation of dendritic cells.
Explore the source record for details and available documents.
Blood Donors↗
Biomedical subjects
V Weisbach
Publications and source records attributed to V Weisbach.
Antibodies to private and public HLA class I epitopes in platelet recipients.
BACKGROUND: Transfusions or pregnancies can cause immunization against private HLA determinants and public epitopes shared by more than one private HLA antigen. HLA antibodies are correlated with febrile transfusion reactions, lower platelet response following platelet transfusion, and an increased rate of renal transplant rejection. Until now, antibody specificities in alloantisera from platelet recipients have been poorly characterized. STUDY DESIGN AND METHODS: Consecutive serum screens from platelet recipients were analyzed for antibodies against private HLA class I antigens and public HLA epitopes using a serum analysis program based on the 2 x 2 table analysis of correlations. Serum screens of highly immunized patients and of patients with new alloimmunization events were reviewed separately. RESULTS: Of the serum screens from 566 platelet recipients, 1577 indicated alloimmunization (panel-reactive antibodies >5%). The program assigned a specificity in 1024 of these screens (64.9%) and at least once in 522 of 566 patients (92.2%). In 267 patients, antibodies detecting public epitopes in the combined A- or B-locus cross-reacting groups were found; other public markers were detected in 39 patients. Patterns of reactivity were remarkably less stable than in patient groups previously studied. In many patients, antibodies with apparent private epitope specificity preceded the identification of antibodies against a shared marker of the same cross-reactive group. However, the disappearance of antibodies (whether or not this was followed by a new antibody against a private or public marker belonging to another cross-reacting group) was also observed. CONCLUSION: The computerized analysis of microlymphocytotoxicity tests enhances the rate of antibody specification in sera from platelet recipients with lymphocytotoxic antibodies. The identified antibodies should be taken into account in the selection of platelet donors. The data confirm and extend previous observations on HLA class I antibodies and elucidate new alloimmunization events.
Antibodies↗
The influence of automated plateletpheresis on systemic levels of hematopoietic growth factors.
BACKGROUND: Megakaryocytopoiesis and platelet production are regulated by several hematopoietic growth factors. The present study focuses on the effects of automated plateletpheresis on systemic levels of different hematopoietic growth factors. STUDY DESIGN AND METHODS: Platelet count, mean platelet volume, and serum levels of thrombopoietin, erythropoietin, interleukin-1beta, interleukin-6, and stem cell factor in 21 healthy donors were measured before platelet collection, after the first half of the apheresis procedure, at the end of apheresis, and on Days 1, 2, and 7 thereafter. RESULTS: Thrombopoietin levels (initial level: 49.5 +/- 25.5 pg/mL) showed a significant increase between measurements taken at the end of apheresis and Day 1 (56.9 +/- 26.7 pg/mL; p = 0.01). There was a highly significant decrease in stem cell factor levels during apheresis (p<0.0005), reaching preapheresis values (1679 +/- 210 pg/mL) on Day 1. A highly significant increase in erythropoietin levels (initial level: 7.5 +/- 4.0 U/L) was seen after apheresis (p<0.0005 on Days 1 and 2). The level remained significantly elevated until Day 7 (p = 0.004). Interleukin-1beta and interleukin-6 levels (before donation: 1.4 +/- 1.8 pg/mL and 1.1 +/- 0.7 pg/mL, respectively) did not change during the observation period. Thrombopoietin levels correlated consistently and inversely with stem cell factor levels after apheresis (Day 1, r = -0.46, p = 0.035; Day 2, r = -0.50, p = 0.02; Day 7, r = -0.50, p = 0.02). CONCLUSION: The data show a coordinated response of the hematopoietic system to platelet loss. It is suggested that the decrease in serum stem cell factor levels during apheresis reflects the consumption of stem cell factor by early hematopoietic progenitors that expand to initiate early megakaryocytopoiesis. The temporary increase in thrombopoietin is the result of platelet loss and serves as a stimulus for subsequent thrombopoiesis. The pronounced elevation of erythropoietin after apheresis suggests a role for this primarily erythropoietic cytokine in thrombopoiesis, too.
Adolescent↗
Comparison of the performance of four microtube column agglutination systems in the detection of red cell alloantibodies.
BACKGROUND: The purpose of this study was to compare the performance of four currently available microtube column agglutination systems in the detection of red cell alloantibodies to that of the standard tube low-ionic-strength solution (LISS) indirect antiglobulin test (IAT) (tube LISS-IAT). STUDY DESIGN AND METHODS: In a comparative study, 172 sera, previously demonstrated to contain red cell alloantibodies, were tested in parallel by the tube LISS-IAT and three microtube column agglutination techniques (DiaMed-ID, Ortho BioVue, and Sanofi-Pasteur Scangel) and one affinity-adherence test system (Gamma ReACT). Tests were performed simultaneously by a single person on freshly thawed sera that had been frozen at -20 degrees C. RESULTS: The rate of detection of clinically significant alloantibodies (n = 154) in microtube column systems was very similar. One hundred forty-one sera (91.6%) reacted in the DiaMed-ID, 139 (90.3%) in the ReACT, 139 (90.3%) in the BioVue, and 142 (92.2%) in the Scangel. Only 117 (76.0%) of these sera reacted in the tube LISS-IAT. The detection rates for 18 antibodies of minor clinical significance (anti-M, -N, -P1, -Le(a), and -Le(b)) varied among the test systems: DiaMed-ID, 5 (28%); ReACT, 7 (39%); BioVue, 14 (78%); Scangel, 10 (56%); and tube LISS-IAT, 6 (33%). Antibody reactivity as determined by titer and score was very similar in all microtube column systems and higher in these systems than in the tube LISS-IAT. CONCLUSION: The sensitivity of all four microtube column systems in the detection of clinically significant red cell alloantibodies was similar and was markedly superior to that of the tube LISS-IAT. An individual cost-benefit analysis should be performed in every institution to decide whether a microtube column system should be applied. If so, the antibody screen in the microtube column agglutination system should ideally be performed in advance of the crossmatch to provide time to screen for compatible units.
Erythrocytes↗
An analysis of errors in blood component transfusion records with regard to quality improvement of data acquisition and to the performance of lookback and traceback procedures.
BACKGROUND: Quality assurance of blood transfusion covers institutions, personnel, and procedures involved in preparing, issuing, and using blood components. The accuracy of data related to blood component transfusions is a tool for quality control in the transfusion service. STUDY DESIGN AND METHODS: A study of the accuracy of data records of the transfusion service at the University Hospital of Erlangen, Germany, between June 1994 and May 1996 was carried out. All returned blood component transfusion report forms were examined for discrepancies between primary data records and clinical transfusion reports. RESULTS: Blood components (n = 49,224) from allogeneic and autologous donations, packed red cells, fresh-frozen plasma, and platelet components that had been issued for transfusion were included in this evaluation. For 27.3 percent of all components issued, no transfusion report was returned to the blood bank. For the remaining 35,786 units, errors were found in 3.8 percent of the records. For 1.24 percent of all components, discrepant information related to the recipient's identity or the component's status was found; this affected the feasibility of lookback or traceback searches. CONCLUSION: A remarkably high frequency of discrepancies exists between computerized blood bank records and the information recorded on returned blood transfusion forms. The processes of data acquisition and entry must be included in quality assurance efforts in transfusion medicine.
Blood Banks↗
Cytokine generation in whole blood, leukocyte-depleted and temporarily warmed red blood cell concentrates.
BACKGROUND AND OBJECTIVES: It has been suggested that inflammatory cytokines such as Interleukin (IL)-1beta, IL-6, tumor necrosis factor-alpha (TNF-alpha) and IL-8 might be responsible for a large number of non-antibody-mediated adverse reactions to the transfusion of blood components, especially of platelet concentrates (PCs). The aim of this study was to compare the levels of proinflammatory cytokines in different blood components containing red cells such as buffy-coat-free packed red cells (RBCs), filtered RBCs and whole blood (WB) during storage under several conditions. MATERIALS AND METHODS: WB (CPD-A1, n = 16) was stored for 35 days at 2-6 degrees C; samples were taken on days 0, 21 and 35. Buffy-coat-poor RBCs in additive solution PAGGS-M (n = 16) were divided into halves, one half was leukocyte (WBC)-depleted by filtration on day 0, both halves were stored for 49 days at 2-6 degrees C (samples: days 0, 21, 49). Furthermore, buffy-coat-poor, unfiltered SAG-M RBCs (n = 16) were halved immediately after production and stored at 2-6 degrees C until day 42 (samples: days 0, 21, 42). One half remained at room temperature for 24 h on day 3. Cytokine levels were determined with commercial enzyme-linked immunosorbent assays. RESULTS: Levels of IL-1beta and TNF-alpha rose during storage of WB and RBCs. IL-6 could be detected markedly above the detection threshold in WB only. At the end of storage, we detected IL-8 in 1 of 16 units of WB tested, in 10 of 16 standard PAGGS-M RBCs and in 15 of 16 temporarily warmed SAG-M RBCs. Prestorage filtration of RBCs prevented the accumulation of IL-1beta and TNF-alpha. Temporarily warming of RBCs for 24 h did not cause any substantial increase in cytokine levels other than IL-8. RBCs stored in different additive solutions (PAGGS-M versus SAG-M) showed similar cytokine concentrations during storage. The cytokine content of WB was very similar to that of buffy-coat-poor RBCs. CONCLUSION: Cytokine levels measured in WB and buffy-coat-poor RBCs result in levels which are unlikely to cause febrile reactions even in the case of massive transfusion. We conclude that, according to present knowledge, there is no reason for prestorage filtration of buffy-coat-poor RBCs or WB to avoid febrile transfusion reactions due to cytokine accumulation during storage.
Blood Preservation↗
A survey of blood utilization in children and adolescents in a German university hospital.
There are no detailed data on blood use with regard to diagnoses of recipients during infancy, childhood and adolescence. Available information on this issue is incomplete and no longer current. We conducted a survey of blood component use in children and adolescents in an acute-care university hospital in the greater area of Nuremberg between June 1994 and September 1996. Packed red blood cells (RBCs), fresh-frozen plasmas (FFPs) and platelet (PLT) components were evaluated for the recipients discharge diagnoses. Source study files were extracted from the hospital transfusion service and the medical records department. Transfused units were listed by broad diagnostic categories and leading diagnostic groups formed from principal diagnoses of the recipients according to the International Classification of Diseases, 9th edn (ICD-9). 34.3% of 2869 RBC cell units, 35.0% of 1095 FFP units and 5.0% of 1028 PLT components were used in patients with congenital diseases, mainly cardiac defects. The disease category neoplastic diseases was next most frequently associated with blood transfusion diagnosed in recipients of 23.9% of all RBCs, 15.6% of all FFP units and in 66.4% of all PLT units. Malignant diseases and benign haematological diseases (diagnostic categories II and IV) accounted for 68.9% of all costs of blood component transfusion. These findings demonstrate the increased importance of platelet transfusion for the organization of local and regional blood donation programmes and for cost analysis exercises. The study shows that detailed information on local blood use may be obtained quickly using available data collections of transfusion services and medical record departments.
Adolescent↗
[Reply to the remarks of A. Lorentz et al].
Explore the source record for details and available documents.
Blood Transfusion↗
Evaluation of a platelet apheresis technique for the preparation of leukocyte-reduced platelet concentrates.
OBJECTIVES: Reduction of the white blood cell (WBC) contamination in platelet concentrates (PC) protects patients from the immunological and infectious side effects of platelet transfusion caused by WBC. This can be done either by filtration of the PC or by improved apheresis techniques that yield WBC-poor preparations. METHODS: To evaluate an improved technique for platelet collection, we carried out 201 separations in 89 healthy cytapheresis donors using the new COBE Spectra leukoreduction system (LRS) and compared the results with those of standard dual-needle separations obtained with the same cell separator. RESULTS: A small but statistically significant difference was found in platelet collection efficiency in comparison with the standard non-LRS software procedures (LRS: 52.6 vs. 56.3% for the reference). However, median WBC contamination was only 0.01 x 10(6) WBC per LRS product. This significant (p < 0.0005) improvement corresponds to a 10-fold reduction of WBC as compared with the standard dual-needle technique. CONCLUSIONS: The COBE Spectra LRS system produced PCs with a platelet collection efficiency nearly equal to previous techniques and with a residual WBC content satisfying even the most stringent criteria for WBC-depleted blood components. As this purity is achieved without important platelet loss, conventional fiber filtration no longer seems necessary in this kind of PC.
Centrifugation↗
Leukocyte depletion and storage of single-donor platelet concentrates.
BACKGROUND AND OBJECTIVES: Because of widespread use of leukocyte reduction in platelet concentrates (PCs) and the need to store such concentrates, we investigated the effects of leukocyte depletion on the quality of stored PCs. MATERIALS AND METHODS: Ten double-sized PCs were divided into 2 equal units which were tested simultaneously. One half was stored for 5 days after filtration through a polyester filter, the other one was stored unfiltered. RESULTS: The volume of the 10 "oversized' PCs was 483 +/- 40 ml (mean +/- standard deviation) and they contained 5.9 +/- 1.5 x 10(11) platelets and 80 +/- 23 x 10(6) leukocytes. Filtration significantly reduced the leukocyte concentration (168 +/- 56/microliter before, 6 +/- 4 /microliter after filtration) and leukocyte count (39.9 +/- 11.3 x 10(6) vs. 1.3 +/- 0.9 x 10(6); p < 0.0005). Filtration caused a platelet loss of 16%, the platelet count decreasing not significantly from 2.91 +/- 0.75 x 10(11) to 2.40 +/- 0.94 x 10(11) (p = 0.26). After 5 days of storage all parameters of platelet function (platelet aggregation to several stimuli, hypotonic shock reaction [HSR] and platelet retraction), mean platelet volume, and pH and pCO2 showed no advantage for PCs filtered prior to storage compared to PCs stored unfiltered. Moreover, platelet aggregation on day 5 using 4 agonists at 10 concentrations showed worse results in 4 assays in prestorage filtered PCs (collagen [4 micrograms/ml: p < 0.05, ADP [0.2 mM]: p < 0.05, ADP [0.3 mM]: p < 0.05, thrombin [0.6 E/ml]: p < 0.05). But there is no convincing trend in all aggregation tests, and HSR, presumably the most useful parameter, was not different or day 5. CONCLUSIONS: There is no advantage in terms of improved quality for prestorage leuko-depletion of PCs. Taking into account the obvious disadvantages of filtration, such as platelet loss and increasing costs per transfusion, we conclude that pre- or post-storage filtration of single-donor PCs should be done only for patients who have a clear indication for the transfusion of leukocyte-poor blood products.
Blood Donors↗
Concomitant alloanti-Jka in a patient with an IgA autoantibody.
Explore the source record for details and available documents.
Aged↗
Comparison of COBE white cell-reduction and standard plateletpheresis protocols in the same donors.
BACKGROUND: It is necessary to protect patients from white cell (WBC)-caused side effects of platelet transfusion by reducing the WBC contamination in single-donor platelets. STUDY DESIGN AND METHODS: A new COBE Spectra WBC (leuko)-reduction system (LRS) was compared to the COBE standard plateletpheresis (standard) procedure. Each of 62 donors underwent plateletpheresis under the two protocols (LRS and standard). The collection efficiency and WBC contamination in the components collected using the techniques were compared. Platelets were counted in a cell counter and WBCs were counted using two full grids of a Nageotte chamber. RESULTS: The preseparation and postseparation numbers for red cells, WBCs, and platelets as well as the number of collected platelets were not different in the two techniques. Collection efficiency in the LRS procedures was 96.2 +/- 13.0 percent of that in the standard procedures. Median WBC contamination in the platelet components was 10,160 per LRS procedure and 56,500 per standard procedure. The purity of the LRS components was significantly improved (p = 0.001), as seen in a comparison of the WBC numbers in components per procedure after log10 transformation (LRS: 0.096 +/- 0.195 x 10(6); standard: 0.390 +/- 1.075 x 10(6)). CONCLUSION: These data suggest that the LRS procedure produces platelet concentrates with a collection efficiency that is comparable to that obtained with the standard technique and with a residual WBC content that satisfies even the most stringent criteria for filtered platelets. As this purity can be achieved without platelet loss or alteration, conventional fiber filtration no longer seems necessary or useful in this type of single-donor platelet component.
Blood Donors↗
A survey of blood component use in a German university hospital.
BACKGROUND: There are no recent studies on transfusion practice and blood use with regard to diagnoses of European recipients. We conducted a survey of blood component use, including packed red cells, fresh-frozen plasma, and platelets, in an acute-care university hospital in the Greater Nürnberg area. STUDY DESIGN AND METHODS: A survey was carried out of blood component transfusion at a university hospital (Erlangen, Germany) between June 1994 and May 1996. Transfused units were listed by broad diagnostic categories formed from principal diagnoses of the recipients according to the International Classification of Diseases, Ninth Revision. RESULTS: Among 100,497 discharged patients, 6,590 patients who received transfusion (6.6%) are represented in this survey. Of 28,440 red cell units and 8,592 fresh-frozen plasma units, 72.4 percent and 66.9 percent, respectively, were used in patients with neoplastic diseases, circulatory system diseases, or disorders of the digestive system. Of 2704 platelet units, 78.1 percent were transfused to patients with neoplastic or gastrointestinal diseases or diseases of blood-forming organs. These four diagnostic categories accounted for 77.7 percent of all costs of transfusion therapy. Males received 60.1 percent of all blood components transfused, and patients less than 65 years old received 68.0 percent. CONCLUSION: This survey provides information on blood component usage in a German university hospital. It demonstrates the concentration of today's blood utilization among a few diagnostic categories. The study shows that detailed information on local blood use may be obtained quickly by using data available from transfusion services and medical record departments. This information is relevant for quality management of transfusion practice, cost analyses and for planning local and regional blood donation programs.
Aged↗
[The importance of quality of whole blood and erythrocyte concentrates for autologous transfusion. Remarks on the work of R. Karger and V. Kretschmer, Anaesthesist (1996) 45:694-707].
Explore the source record for details and available documents.
Blood Transfusion, Autologous↗
Stem cell separation in paediatric patients.
We performed 28 separations in 11 children weighing from 14 to 72 kg (median: 27 kg) using either the Cobe Spectra or the Fresenius AS 104 cell separator. For children under 20 kg, human albumin solution was used for the last 200 mL of the priming procedure instead of NaCl. Blood flow was reduced to 30-50 mL min-1 depending on the children's size and weight to prevent citrate reactions. Within 149-337 min we processed three times the patients' total blood volume and collected 309.7 x 10(6) (102.9-1140.0) mononuclear cells (MNC) and 2.01 x 10(6) (1.90-6.50) CD34+ cells per kg body weight. These results were comparable to the results we previously obtained in adults. We conclude from these initial results that peripherae blood stem cells (PBSC) separations, with both devices, can be adapted successfully to the needs of paediatric patients.
Antigens, CD34↗
[Iron homeostasis in preoperative autologous blood donation].
OBJECTIVE: The role of iron metabolism, the value and the limits of oral as well as intravenous iron substitution in preoperative autologous blood donation are discussed according to the literature. DATA SOURCES AND SELECTION CRITERIA: The critical review of the German and English literature is based on a Medline backsearch covering the last 20 years. RESULTS: The success of preoperative autologous blood donation substantially depends on the volume of whole-body iron and on the amount of storage iron which is available at the beginning of the donation phase. Since iron losses due to repeated blood donations within a few weeks cannot be replaced sufficiently by food, medical iron substitution seems to be appropriate. Nevertheless, hitherto neither oral nor intravenous iron substitution could be demonstrated as useful instruments for an improvement of erythropoietic response in non iron deficient patients after autologous blood donation. Merely, intravenous iron used in combination with recombinant erythropoietin seems to be an effective support for erythropoiesis during predeposit. CONCLUSIONS: At the moment intravenous iron medication in autologous blood donation should be restricted to well-established exceptional cases. The use of intravenous iron combined with erythropoietin seems to be justified to avoid ineffective erythropoieses and to achieve a dose reduction of recombinant erythropoietin. Since there are nearly no risks and a possible efficacy cannot be totally excluded, oral iron supplementation may be applied to patients who tolerate it well. Real iron deficiency has to be treated with iron application. Further clinical studies have to be done for a final validation of the efficacy of iron substitution in non iron deficient preoperative autologous blood donors.
Blood Loss, Surgical↗
Separation of peripheral blood derived stem cells in children.
We performed 28 separations in 10 children from 14 to 44 kg (median: 24 kg) using either the Cobe Spectra or the Fresenius AS 104 cell separator. For children below 20 kg, human albumin solution was used for the last 200 ml of the priming procedure instead of NaCl. Blood flow was reduced to 30 - 50 ml/min depending on the childrens' size and weight to prevent citrate reactions. Within 149 - 337 minutes we processed 3 x the patients' total blood volume and collected 326.9 x 10(6) (76.5-1, 140.0) MNC and 2.03 x 10(6) (0.14-10.12) CD34+ cells per kg body weight. These results were comparable to the results we previously obtained in adults. We conclude from these initial results that PBSC separations with both devices can be adapted successfully to the needs for paediatric patients.
Adolescent↗
[Expanded serologic infection testing of autologous blood donors: a report of experiences].
PURPOSE: The transmission of hepatitis B virus (HBV), hepatitis C virus (HCV), or human immunodeficiency virus (HIV-1/2) may cause serious disease in the recipient in cases of inadvertant homologous transfusion of autologous blood. Therefore data on the incidence of these infections in autologous blood donors are necessary. METHODS: We tested 7,438 autologous donations from 3,030 patients for anti-HIV, anti-HCV, and HBsAG. In addition, we tested all patients for antibodies to Treponema pallidum and hepatitis B virus core antigen (anti-HBc) and for elevated serum ALT levels. Confirmation tests were performed only for positive anti-HIV-EIAs. RESULTS: The frequencies of anti-HIV, anti-HCV, and HBsAG were 0.05, 2.8 and 0.6% of all units. The rate of anti-HCV decreased from 4.0 to 3.4% after introduction of a 2nd generation EIA but was only 0.6% using a 3rd generation EIA. Anti-HBc was positive in 9.4%, the TPHA test in 0.5%. ALT was above 45 U/I in 1.2%, but outside the sex related normal range in 8.4% of all units. 23.7% of all donations positive for anti-HIV, anti-HCV, or HBsAG showed at least one pathologic surrogate test; 7.5% of all surrogate marker positive units contained anti-HIV, anti-HCV, or HBsAG. DISCUSSION: The overall frequency of anti-HIV, anti-HCV, and HBsAG was only 3.45% of all autologous donations and was reduced further after introduction of 2nd and 3rd generation anti-HCV-EIAs. However, the rate of surrogate marker positive units was 10.9%. The overlap between both groups was remarkable. We conclude from our data that procedures to minimize the risk of inadvertant homologous transfusion of autologous blood are necessary despite the implementation of screening tests in autologous donation programs.
Adolescent↗