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R Eckstein

Publications and source records attributed to R Eckstein.

At least 55 records · Page 3Linked to original sources
PubMed1997

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↗
PubMed1997

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↗
PubMed1997

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↗
PubMed1997

A multicenter evaluation of the routine use of a new white cell-reduction apheresis system for collection of platelets.

BACKGROUND: Residual white cells (WBCs) cause serious side effects in platelet transfusion. An in-line WBC-reduction system based on fluidized particle bed technology was recently developed as a modification of an existing plateletpheresis system. STUDY DESIGN AND METHODS: In an investigational phase, three flow profiles were evaluated using prototype software in five centers, each using their standard conditions. In the confirmatory phase, the released software was tested in three centers. WBCs were counted in two full Nageotte grids (dilution 1-in-5). RESULTS: With the prototype software, WBC levels were always below 1 x 10(6) per procedure (median, 25,000/procedure; n = 314). One profile proved to be superior to the other two with respect to platelet yield and residual WBCs, and it was incorporated in the released WBC-reduction system, together with a built-in process control. Median residual WBCs in these WBC-reduction system components not rejected by the process control were 19,000 per procedure (n = 211/225 total), with 99.5 percent of the platelet components having less than 1 x 10(6) WBCs. CONCLUSION: The protocol selected in the initial phase, now available as a WBC-reduction system, results in platelet concentrates with very low residual WBC levels. This satisfies even the most stringent criteria for WBC reduction in platelets, without the platelet loss typically seen with conventional fiber filtration.

Blood Platelets↗
PubMed1997

Idiopathic subglottic stenosis: diagnosis and endoscopic laser treatment.

The records of 15 patients with idiopathic subglottic stenosis treated at Royal North Shore Hospital, Sydney, between 1980 and 1994 were reviewed. All were female and had similar characteristic clinical and histopathologic features. Endoscopic laser vaporization was the primary treatment in 12 patients and was successful in maintaining the airway of 8 of these 12; this outcome indicates that the disease can be managed, at least initially, by endoscopic laser treatment in most cases.

Adolescent↗
PubMed1996

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↗
PubMed1996

[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↗
PubMed1996

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↗
PubMed1996

[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↗
PubMed1995

Autografting with blood progenitor cells: predictive value of preapheresis blood cell counts on progenitor cell harvest and correlation of the reinfused cell dose with hematopoietic reconstitution.

One hundred and nine patients suffering from various malignancies underwent 285 apheresis procedures for PBPC collection. A median of two leukaphereses (range: 2-5) resulted in median numbers of 4.6 x 10(8) MNC/kg, 14.1 x 10(4) CFU-GM/kg, and 6.0 x 10(6) CD34+ cells/kg. Preleukapheresis peripheral blood CD34+ cells correlated significantly with collected CD34+ cells/kg (r = 0.94; p < 0.0001) and with CFU-GM/kg (r = 0.52; p < 0.0001). A value > 4 x 10(4) CD34+ cells/ml was highly predictive for a collection yield > 2.5 x 10(6) CD34+ cells/kg harvested by a single leukapheresis. Sixty patients were evaluated for hematologic reconstitution and engrafted in a median time of 10 days for WBC > 1.0 x 10(9)/l (range: 7-21 days), 10 days for ANC > 0.5 x 10(9)/l (7-20) and 11 days for PLT > 20 x 10(9)/l (7-62). Reinfused CD34+ cells/kg correlated significantly with hematologic engraftment (r = 0.44-0.52 and p < 0.006-0.001) as well as CFU-GM/kg (r = 0.36-0.44 and p < 0.007-0.001). A progenitor cell dose > 2.5 x 10(6) CD34+ cells/kg or > 8.0 x 10(4) CFU-GM/kg led to a significantly faster recovery for WBC, ANC, and PLT when compared with patients receiving < 2.5 x 10(6) CD34+ cells/kg or < 8.0 x 10(4) CFU-GM/kg. We conclude that rapid hematopoietic engraftment after high-dose therapy and PBPC reinfusion correlates well with a progenitor cell dose > 2.5 x 10(6) CD34+ cells/kg or > 8.0 x 10(4) CFU-GM/kg, and that above a preleukapheresis threshold of 4 x 10(4) CD34+ cells/ml a PBPC autograft containing > 2.5 x 10(6) CD34+ cells/kg can be collected by a single leukapheresis. We suggest that patients recovering from myelosuppression should be monitored for CD34+ cells in serial blood samples to determine the course of circulating hematopoietic progenitor cells. This issue will help to define the optimal time point to start apheresis and to predict a PBPC autograft harvested by a single leukapheresis, which will lead to rapid and stable hematopoietic reconstitution following transplantation.

Adolescent↗
PubMed1994

Microbiologic contamination of peripheral blood stem cell autografts.

We have determined the incidence and clinical significance of positive microbiologic cultures in a series of 290 peripheral blood stem cell concentrates in 95 patients undergoing multiple apheresis procedures for autologous stem cell rescue. Specimens for bacterial cultures were obtained after processing of the autografts just prior to freezing. The incidence of microbial contamination was 4.5% (n = 13). The predominant pathogenic microorganism cultured was coagulase-negative Staphylococcus (n = 11). From 8 patients with contaminated leukapheresis products 6 underwent autologous stem cell transplantation. Five patients received 1-5 culture-positive stem cell concentrates without serious sequelae, whereas the sixth patient was autografted with noncontaminated leukapheresis products, 1 concentrate contaminated with Aspergillus fumigatus being not reinfused. No microorganism present in the stem cell autograft was recovered in vivo in the posttransplantation period, although fever as a sign of infection occurred in all but 1 patient. Peripheral blood stem cell collection and ex vivo processing for cryopreservation may result in microbiologic contamination. However, our data show that infusion of contaminated stem cell autografts does not play a significant role as a source for infections in the clinical setting of autologous stem cell rescue.

Adolescent↗
PubMed1994

Identification of antibodies toward private and public class I HLA epitopes in sensitized patients.

BACKGROUND: Antibodies to HLA determinants may decrease the increment after platelet transfusion and are correlated with increased rates of rejection in renal transplantation. Cross-match tests and HLA antibody specification are used to identify compatible donors for sensitized patients. However, search for cross-match negative donors may be ineffective, and many sera containing antibodies toward public HLA epitopes give no clear results in conventional specificity analysis. MATERIALS AND METHODS: We tested a series of 4,625 sera from 1,073 patients with hematological, malignant or other diseases using a fluorescence lymphocytotoxicity test (LCT). We applied an evaluation program incorporating a list of public antigens belonging to known cross-reacting groups (CREGs) to detect antibodies toward private and just as well public epitopes. RESULTS: In 694 sera (15.0%) from 240 patients the panel reactivity (PRA) in LCT assay was higher than 5%. PRA was > or = 50% in 258 (37.2%) and < 50% in 436 sera (62.8%). In both groups we identified specific antibodies toward public HLA class I epitopes. Overall antibody specification was successful in 429 of 694 sera (61.8%) and in 175 of 240 patients (72.9%), respectively. The rate of antibodies against public epitopes shared by more than one HLA class I gene product was 203/694 (29.3%) with respect to tested sera and 83/240 (34.5%) with respect to patients. The rate of public epitope antibodies was highest in sera with PRA values from 30 to 90% showing public epitope specificity in 159 of 353 sera (45.0%). CONCLUSIONS: We conclude that antibodies toward public HLA class I determinants are detectable not only in highly sensitized patients. The described program may increase the rate of antibody specification and facilitate the platelet supply in platelet refractory patients.

Blood Grouping and Crossmatching↗
PubMed1994

[HLA and transfusion].

Using published data, the role of the HLA system for transfusion of cellular blood components is described. Transfusion-associated immunomodulation and the causative role of HLA in other side effects of transfusion therapy are discussed, using review articles and original papers from the German and English literature as sources. The HLA system has important implications for transfusion therapy. Sensibilization of recipients with consecutive formation of HLA antibodies impairs the support of thrombocytopenic patients and may cause febrile transfusion reactions. HLA antibody formation in donors may result in transfusion-induced acute lung injury. The transfusion of viable lymphocytes may cause graft-versus-host disease in immunocompromised recipients or after directed donations from relatives, in rare cases even without these conditions. The clinical implications of transfusion-associated immunomodulation are judged differently.

Blood Component Transfusion↗
PubMed1994

[18 months experience with a new single needle cytapheresis system (Fresenius AS 104 SN)].

BACKGROUND: Since October 1991 the third-generation cell separator Fresenius AS 104 offers a single-needle (SN) option for thrombocytapheresis. Here we present our first 18-month experience with this new single-needle system. MATERIALS AND METHODS: We performed 395 thrombocytaphereses in 225 donors. The influence of blood flow, cycle volume, and interface position on efficacy and leukocyte contamination was evaluated. RESULTS: 395 thrombocytaphereses were performed with an average thrombocyte yield of 3.00 +/- 0.69 x 10(11) platelets and a leukocyte contamination of 1.66 +/- 3.1 x 10(8) per concentrate. Blood flow rates of 50 ml/min (vs. 60 ml/min) and an interface position of 6:2 (vs. 7:1) resulted in a lower leukocyte contamination, but without statistical significance. CONCLUSION: The SN program of the AS 104 provides high thrombocyte yields and less leukocyte contamination than other SN systems, but 77% of the concentrates still contain more than 0.5 x 10(8) leukocytes.

Adult↗