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Biomedical subjects

R Eckstein

Publications and source records attributed to R Eckstein.

At least 37 records · Page 2Linked to original sources
PubMed2000

In vitro characteristics of red blood cell concentrates prepared from under- and overcollected units of whole blood and from a paediatric blood bag system.

The problem of how to deal with red blood cell concentrates (RBCs) prepared from under- or overcollected units of whole blood (WB) and how to collect blood from underweight persons arises in the context of autologous predeposit. To determine the quality of RBCs stored in PAGGS-M additive solution prepared from under- and overcollected units of whole blood and of PAGGS-M RBCs prepared from a paediatric 250-mL top outlet blood bag system we measured blood picture, haemolysis, K+, pH, ATP and 2,3-DPG on days 0, 10, 20, 30, 40 and 49 of storage. The volume of WB collected ranged from 150 to 600 mL in 50-mL increments (4 units per volume). Haemolysis was under 0.8% on day 49 in all RBCs prepared from WB donations between 200 mL and 600 mL. However, the day 49 haemolysis level of standard RBCs prepared from 450 mL of WB (0.15 +/- 0.03%) was reached earlier in RBCs from under- and overcollected units of whole blood. 2,3-DPG levels decreased rapidly between days 10 and 20 in all RBCs studied. RBCs from 450-mL donations showed acceptable ATP maintenance after 49 days (70.4% of day 0 value), while all other RBC ATP levels were below 50% of the day 0 level on day 49. In vitro quality data of RBCs prepared from a 250-mL donation in the paediatric blood bag system after storage for about 25 days were comparable to those after 49 days of storage of standard RBCs. Our results suggest that it is feasible to transfuse PAGGS-M RBCs prepared from under- as well as overcollected units of WB in the autologous setting. However, we strongly recommend shortening the storage period of such RBCs to maintain the quality level of standard RBCs.

Blood Donors↗
PubMed2000

Periodic alternating interface positioning to lower WBC contamination of apheresis platelet concentrates: a multicenter evaluation.

BACKGROUND: A new software version of a cell separator (AS TEC 204, Fresenius) providing WBC-reduced single-donor plateletpheresis concentrates was tested. STUDY DESIGN AND METHODS: Dual-needle apheresis procedures (n = 621) were performed in three centers, using either fixed interface positioning (FIP) or periodic alternating interface positioning (PAIP). The other separation parameters (e.g., anticoagulant:whole-blood ratio, and blood flow) were set individually. All platelet concentrates were evaluated for platelet yields and contaminating WBCs. RESULTS: The introduction of the PAIP resulted in a significant (p<0.001) reduction in contaminating WBCs (median, 30,000) from the numbers seen with FIP (median, 2,300,000) while maintaining the separation efficacy (47%) and separation time. Ninety-eight percent of all concentrates contained less than 5 x 10(6) WBCs per concentrate and 92 percent contained less than 1 x 10(6). CONCLUSION: Plateletpheresis using the AS TEC 204 cell separator with PAIP is a valid alternative to WBC reduction by filtration. It may provide WBC-reduced platelet concentrates without the additional cost of filters. However, the reliability of the WBC reduction is not yet advanced enough that PAIP can be employed without any monitoring of the end product.

Blood Platelets↗
PubMed1999

Oral or intravenous iron as an adjuvant to autologous blood donation in elective surgery: a randomized, controlled study.

BACKGROUND: This study was performed to evaluate the capacity of oral and intravenous (i.v.) iron administration during autologous blood donation (ABD) to improve the efficacy of ABD and to prevent the need for allogeneic blood transfusion in patients without iron deficiency who are undergoing major elective surgery for which a minimum of 3 autologous units have been ordered. STUDY DESIGN AND METHODS: One hundred twenty-three patients were enrolled in an open-labeled, randomized, controlled trial and assigned to three treatment groups: patients in Group 1 received 3 x 100 mg of Fe2+ per day given orally for 5 weeks before operation; patients in Group 2 received 200 mg of Fe3+ given intravenously after each donation combined with initial i.v. iron supplementation in patients with hemoglobin under 15 g per dL; and patients in Group 3 were in the control group that received no iron medication. A modest ABD program involving weekly phlebotomy and threshold hemoglobin values for donation of 11.5 g per dL in women and 12.0 g per dL in men was performed. RESULTS: Ninety patients, 15 women and 15 men in each of the three groups, completed the study. The mean net red cell production during ABD was no higher (p>0.2) in the iron-treated groups (Group 1: 473 +/- 178 mL; Group 2: 436 +/- 170 mL; Group 3 (controls): 397 +/- 174 mL). The mean number of autologous units donated per patient did not differ (p>0.7) among the groups (Group 1: 3.1 +/- 0.6; Group 2: 2.9 +/- 0.7; Group 3: 3.0 +/- 0.7). The proportion of patients who needed allogeneic blood transfusion showed no significant (p>0.4) advantage for iron treatment, (Group 1: 7%; Group 2: 20%; Group 3: 10%). CONCLUSION: In non-iron-deficient patients undergoing modest ABD without erythropoietin therapy, neither oral nor i.v. application of iron during the preoperative period enhances the success of preoperative ABD.

Administration, Oral↗
PubMed1999

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↗
PubMed1999

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↗
PubMed1999

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↗
PubMed1999

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↗
PubMed1999

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↗
PubMed1998

Surgery for intestinal graft-versus-host disease: report of two cases.

PURPOSE: With allogeneic bone marrow transplantation becoming increasingly common, intestinal graft-versus-host disease often is seen within specialized transplant units. Surgeons are involved infrequently in the management of such patients, and yet occasionally are called upon to operate on critically ill patients with refractory disease. This article reviews the salient features of this condition and discusses possible indications for surgery. METHOD: Two cases of intestinal graft-versus-host disease that required laparotomy are presented. RESULTS: A 24-year-old male with severe, unremitting, acute intestinal graft-versus-host disease underwent small-bowel and large-bowel resections for massive bleeding. A 35-year-old male with recurrent symptoms of small-bowel obstruction after allogeneic bone marrow transplantation underwent small-bowel resection and multiple strictureplasties for chronic intestinal graft-versus-host disease. CONCLUSION: Surgery can be performed for complications of intestinal graft-versus-host disease not responding to medical therapy, with successful outcome.

Adult↗
PubMed1998

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↗
PubMed1998

Bacterial contamination of autologous bone marrow: reinfusion of culture-positive grafts does not result in clinical sequelae during the posttransplantation course.

OBJECTIVES: Microbiological cultures and posttransplantation course were analyzed in order to investigate the incidence and clinical significance of bacterial contamination of autologous bone marrow (BM) grafts. METHODS: Cultures were obtained from BM after collection, BM concentrate after processing, contaminated/cryopreserved BM at thawing, and from peripheral blood (PB) following autologous BM transplantation (ABMT). The posttransplantation course of patients grafted with culture-positive BM was recorded and compared with patients who underwent ABMT with noncontaminated BM grafts. RESULTS: In 239 BM grafts processed, the incidence of microbiological contamination was 26.4% (n = 63). Fifty marrow grafts were contaminated by bacteria from the skin flora: coagulase-negative Staphylococcus (CNSC), Propionibacterium, and Corynebacterium species (79%). Thirty-eight patients underwent ABMT (day 0) with cryopreserved culture-positive BM, and 32 patients were evaluable for microbiological cultures at thawing: in 10 of 32 BM grafts CNSC was found prior to reinfusion. Following ABMT, PB cultures revealed CNSC in 5 of 38 patients between days +4 and +12. However, the late occurrence of positive PB cultures after BM reinfusion made a relationship between BM CNSC and PB CNSC unlikely. In 33 of 38 patients, no graft-contaminating bacteria were detected in PB. Comparison of the posttransplantation course of patients who received contaminated BM with that of patients grafted with noncontaminated BM showed no significant differences concerning time to engraftment, febrile days, and days on antibiotics. CONCLUSION: (1) Collection and/or ex vivo processing can result in microbiological contamination of BM grafts predominantly with bacteria from the skin flora, and (2) only CNSC can be cultured at thawing from previously contaminated/cryopreserved BM. Since patients undergoing ABMT usually receive oral antibiotics from beginning of the conditioning regimen which are active against CNSC, no further administration of antibiotics is recommended for the reinfusion of bacterially contaminated BM grafts.

Adolescent↗
PubMed1998

Corneal scarring and irregular astigmatism following refractive surgery in a corneal transplant.

BACKGROUND: Scarring may follow refractive surgery, causing irregular astigmatism and loss of visual acuity. METHODS: A case report of scarring and irregular astigmatism occurring in a corneal transplant following photorefractive keratectomy and arcuate incisions is presented. RESULTS: Following surgical excision of the scar, unaided visual acuity improved from 1/60 to 6/12. Histopathology of the excised scar was obtained. CONCLUSIONS: Refractive surgery following corneal transplantation may produce scarring. The origin of the scar in the present case has not been established.

Adult↗
PubMed1998

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↗