bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of the Amicus Separator in the collection of apheresis platelets
Authors: Yockey C. , Murphy S. , Eggers L. , Garratty G. , Dingle A. , Helms C. , Moroff G. 
Published: March 2003

BACKGROUND: A new apheresis instrument, the Amicus Separator with software versions 2.13 and 2.34, was evaluated for component yields, collection efficiency, and incidence of donor and transfusion recipient reactions. The Amicus was also compared to the Spectra Leukocyte Reduction System (LRS) with version 5 software.STUDY DESIGN AND METHODS: Single and double apheresis platelets (APs) were collected at two locations. The targeted platelet yields were 4.0 × 10(11) for single APs and 6.8 × 10(11) for double APs. One location used a double‐ needle procedure, and the other used a single‐needle procedure. Along with 28 of the Amicus procedures (14 at each of two locations), the same donors underwent single or double AP collections on the Spectra LRS. APs were tested for platelet yields and residual white cells. APs were transfused in three hospitals. Donor and transfusion recipient reactions and technical problems were documented.RESULTS: The Amicus Separator efficiently collected single APs (n = 59) and double APs (n = 62) with mean platelet yields of 4.2 × 10(11) and 6.5 × 10(11), respectively. When inlet line alarms occurred in single‐needle procedures, platelet yields were lower and collection times were longer. All APs were white cell‐reduced below 5.0 × 10(6), and all but one AP were white cell‐reduced below 1.0 × 10(6) without filtration. Component yields from the paired Amicus and Spectra LRS procedures were comparable. Collection times (excluding reinfusion/rinseback) were 20 to 23 minutes faster on the Amicus Separator. No serious donor or transfusion recipient reactions occurred.CONCLUSION: The Amicus Separator provided satisfactory platelet yields and collection efficiency, with shorter collection times than did the Spectra LRS, and it white cell‐reduced components without filtration.
Allogeneic blood progenitor cell collection in normal donors after mobilization with filgrastim: the M.D. Anderson Cancer Center experience
Authors: Anderlini P. , Donato M. , Chan K.‐W. , Huh Y.O. , Gee A.P. , Lauppe M.J. , Champlin R.E. , Körbling M. 
Published: March 2003

BACKGROUND: Information on the safety and efficacy of allogeneic peripheral blood progenitor cell (PBPC) collection in filgrastim‐mobilized normal donors is still limited.STUDY DESIGN AND METHODS: The PBPC donor database from a 42‐month period (12/94‐5/98) was reviewed for apheresis and clinical data related to PBPC donation. Normal PBPC donors received filgrastim (6 μg/kg subcutaneously every 12 hours) for 3 to 4 days and subsequently underwent daily leukapheresis. The target collection was ≥4 × 106 CD34+ cells per kg of recipient's body weight.RESULTS: A total of 350 donors were found to be evaluable. Their median age was 41 years (range, 4‐79). Their median preapheresis white cell count was 42.8 × 109 per L (range, 18.3‐91.6). Of these donors, 17 (5%) had inadequate peripheral venous access. Leukapheresis could not be completed because of apheresis‐related adverse events in 2 donors (0.5%). Of the 324 donors evaluable for apheresis yield data, 221 (68%) reached the collection target with one leukapheresis. The median CD34+ cell dose collected (first leukapheresis) was 462 × 106 (range, 29‐1463). The main adverse events related to filgrastim administration in donors evaluable for toxicity (n = 341) were bone pain (84%), headache (54%), fatigue (31%), and nausea (13%). These events were rated as moderate to severe (grade 2‐3) by 171 (50%) of the donors. In 2 donors (0.5%), they prompted the discontinuation of filgrastim administration.CONCLUSION: PBPC apheresis for allogeneic transplantation is safe and well tolerated. It allows the collection of an “acceptable” PBPC dose in most normal donors with one leukapheresis, with minimal need for invasive procedures.
Corrected count increment and percent platelet recovery as measures of posttransfusion platelet response: problems and a solution
Authors: Davis K.B. , Slichter S.J. , Corash L. 
Published: March 2003

BACKGROUND: Corrected count increment (CCI) and percent platelet recovery (PPR) are measures of response to platelet transfusion that “correct” the count increment for blood volume and number of platelets transfused. Their potential for data distortion is described, and a regression analysis is suggested that is more informative and avoids the inherent problems associated with using ratios as outcome measures.STUDY DESIGN AND METHODS: Data from the first platelet transfusion for 585 patients from the Trial to Reduce Alloimmunization to Platelets (TRAP) were used to model methods of analyzing posttransfusion platelet response.RESULTS: By linear regression analysis, unfiltered platelet components gave a greater posttransfusion increment on average (p = 0.001), but filtered platelets gave a greater increment per platelet transfused (p = 0.003). In contrast, CCI and PPR showed no difference between filtered and unfiltered platelets (p = 0.36 and p = 0.29, respectively) because they combined the effects of dose, filtration, and patient size. Slightly fewer patients are required for a study analyzed by regression analysis.CONCLUSION: Regression analysis of posttransfusion platelet increments should be used instead of CCI or PPR to compare the efficacy of platelet components. CCI and PPR should not be used to define platelet refractoriness as a study outcome, because these measures are biased in favor of platelet preparation techniques that provide fewer platelets.
Platelet membrane integrity during storage and activation
Authors: Reid T.J. , Esteban G. , Clear M. , Gorogias M. 
Published: March 2003

BACKGROUND: The platelet cell membrane appears to undergo a lipid‐phase transition on cooling from 23°C to 4°C. Consequences of this phase transition are leakage of cellular material and irreversible cellular damage. Whether agents, of known benefit in protecting membranes and proteins from cooling and drying injury, could also protect platelets was investigated. Leakage of cytosolic components was assessed by measuring the release of fluorescein into the surrounding medium.STUDY DESIGN AND METHODS: Fresh platelets were suspended in 5 percent dimethyl sulfoxide (DMSO) or in 5 mM of one the following agents: glucose, trehalose, sucrose, glycerol, ethylene glycol, 1,2‐propanediol, or l‐proline. Platelets were loaded with 10 nM fluorescein diacetate (FD), chilled at 4°C for 24 hours or frozen at –1°C per minute to –70°C, warmed rapidly at 37°C, and centrifuged, and the supernatant was measured for the presence of fluorescein. The effect of FD on platelets was assessed by agglutination with ristocetin, aggregation with thrombin and ADP, platelet‐induced clot retraction, and expression of p‐selectin. Platelet function and activation before and after freezing or cooling were measured by the same methods.RESULTS: By flow cytometry, 98 percent of the platelets incorporated FD. The trapped fluorescein resulted in neither platelet activation (p = 0.9) nor reduction of platelet function (p = 0.12‐0.94) from that in control platelets. Freezing of platelets in DMSO caused far less release of fluorescein than did freezing with other agents (p<0.001) or chilling of platelets at 4°C for 24 hours (p<0.0001). Supernatant levels of fluorescein correlated inversely with platelet function. Fluorescein was also shown to be released during aggregation with thrombin or ADP but not during agglutination with ristocetin.CONCLUSIONS: Release of fluorescein into the surrounding medium indicated a loss of platelet membrane integrity and function. Cellular loading with FD is a simple method of studying membrane integrity of platelets and other cells.
Risk of bacterial infection associated with allogeneic blood transfusion among patients undergoing hip fracture repair
Authors: Carson J.L. , Altman D.G. , Duff A. , Noveck H. , Weinstein M.P. , Sonnenberg F.A. , Hudson J.I. , Provenzano G. 
Published: March 2003

BACKGROUND: The relationship between allogeneic blood transfusion and bacterial infection remains uncertain. An increased risk of bacterial infection would represent the most important risk of allogeneic transfusion, because viral disease transmission has become so rare.STUDY DESIGN AND METHODS: A retrospective cohort study of 9598 consecutive hip fracture patients at least 60 years old who underwent surgical repair was performed. The primary outcome was serious bacterial infection, defined as bacteremia, pneumonia, deep wound infection, or septic arthritis or osteomyelitis. Secondary outcomes included two individual infections, pneumonia and urinary tract infection (UTI), and the cost of infection. Hospital cost of infection was assessed by linking the study population to Medicare data.RESULTS: Fifty‐eight percent of patients received at least one transfusion. Serious bacterial infection occurred in 437 patients (4.6%); 28.8 percent of this group died during the hospital stay. Pneumonia occurred in 361 patients (3.8%) and UTI occurred in 1157 patients (12.1%). The adjusted risk of serious bacterial infection associated with transfusion was 1.35 (95% CI, 1.10‐1.66). The adjusted risk for pneumonia was 1.52 (95% CI, 1.21‐1.91), and that for UTI was 1.03 (95% CI, 0.91‐1.17). A dose‐response relationship was present for serious bacterial infection (p = 0.001) and pneumonia (p = 0.001). The cost of hospitalization was $14,000 greater for patients with serious infection than for patients without infection.CONCLUSION: Blood transfusion is associated with a 35‐percent greater risk of serious bacterial infection and a 52‐percent greater risk of pneumonia. Postoperative infections are costly. The risk of bacterial infection may be the most common life‐threatening adverse effect of allogeneic blood transfusion.
Comparison of the performance of four microtube column agglutination systems in the detection of red cell alloantibodies
Authors: Weisbach V. , Ziener A. , Zimmermann R. , Glaser A. , Zingsem J. , Eckstein R. 
Published: March 2003

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°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, ‐Lea, and ‐Leb) 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.
Prevalence of GB virus type C/hepatitis G virus RNA and anti‐E2 among blood donors in Southeastern France
Authors: Cantaloube Jean‐François , Gallian Pierre , Biagini Philippe , Attoui Houssam , Escher Jacqueline , Zappitelli Jean‐Pierre , Delord Yves , De Micco Philippe , De Lamballerie Xavier 
Published: March 2003

BACKGROUND: The purpose of the study was to analyze serologic and molecular markers of the GB virus type C/hepatitis G virus (GBV‐C/HGV) infection in voluntary blood donors from Southeastern France.STUDY DESIGN AND METHODS: Sera were tested for the presence of GBV‐C/HGV RNA by reverse transcriptase‐polymerase chain reaction and that of antibodies to the GBV‐C/HGV E2 (anti‐E2) antigen by an enzyme‐linked immunosorbent assay. A first cohort (1660 blood donors) was tested prospectively and a second cohort (238 samples with hepatitis markers) was tested retrospectively. Donors in the prospective study were questioned for possible risk factors of virus transmission. Amplification products were sequenced and subjected to phylogenetic analysis.RESULTS: Approximately 2.6 percent of individuals accepted for blood donation and 15.4 percent with positive hepatitis C virus serologic tests carried GBV‐C/HGV RNA. Anti‐E2 was detected in these two populations in approximately 12 percent and 48 percent of donors, respectively. Moderate relative risks were found only in tattooed or pierced individuals (1.82) and health care workers (2.45). Almost all strains were located in the same phylogenetic branch as HGV Group 2.CONCLUSION: Though a large proportion of the donors tested have been in contact with GBV‐C/HGV, no elevated relative risk of infection was identified. The phylogenetic distribution of viral strains suggests that the infection is endemic in this population.
Ceftizoxime‐induced hemolysis due to immune complexes: case report and determination of the epitope responsible for immune complex‐mediated hemolysis
Authors: Endoh Teruo , Yagihashi Atsuhito , Sasaki Masateru , Watanabe Naoki 
Published: March 2003

BACKGROUND: Several occurrences of immune complex‐mediated, cephalosporin‐induced intravascular hemolysis have been reported. This report describes the first case of hemolytic anemia caused by an immune‐complex mechanism associated with ceftizoxime and delineates the epitope responsible for hemolysis.CASE REPORT: The patient's serum was tested for antibody that reacted with five penicillins and 30 cephems (all types of cephalosporins) by using protocols to detect drug‐adsorption and immune‐complex mechanisms. The patient's antibody that formed immune complexes with ceftizoxime reacted with 10 of 30 cephems. These 10 drugs were classified as oxime‐type cephalosporins, which have a common structural formula consisting of [(Z)‐2‐(2‐amino‐4‐thiazolyl)‐2‐methoxyiminoacetoamido] at the C7 position on 7‐aminocephalosporinic acid with or without substitution at the C3 position.CONCLUSION: The patient's antibody recognized a common structure in 10 oxime‐type cephalosporins, and immune complexes formed by the antibody specifically or nonspecifically bound to red cell membranes. Therefore, when intermittent antibiotic therapy is required, as in this case, care should be taken in antibiotic selection to avoid drug‐induced hemolytic anemia. In addition, when this type of hemolysis is observed, tests for antibody that reacts by adsorption and immune‐complex mechanisms should be performed against penicillins and cephems to select antibiotics not showing a cross‐reaction.
Where does preoperative erythropoietin therapy count? A mathematical perspective
Authors: Brecher Mark E. , Goodnough Lawrence T. , Monk Terri 
Published: March 2003

BACKGROUND: The administration of erythropoietin (EPO) can be used to increase a patient's hematocrit (Hct) in the preoperative period and thus possibly preclude the need for allogeneic red cells. However, the exact effect on the postoperative Hct of a given rise in Hct in the preoperative period (and on the avoidance of allogeneic blood) has not been thoroughly evaluated.STUDY DESIGN AND METHODS: Equations were developed on the basis of previously described relationships that allowed the assessment of the impact of a given preoperative Hct increase on the postoperative Hct under a variety of clinical situations.RESULTS: Equations were derived that related the change in preoperative Hct after the administration of EPO to the final Hct after a given blood loss. In a typical example (blood volume = 5000 mL, pre‐EPO Hct of 40%, post‐EPO Hct of 45% after blood losses of 1000, 2000, 3000, 4000, 5000, and 6000 mL), an additional 205, 168, 137, 112, 92, and 75 mL of red cells, respectively, would be present postoperatively over the volume in the same patient who did not receive EPO. For a smaller patient, such as a child (blood volume, 2500 mL), an additional 17 mL (5000‐mL blood loss) to 83 mL (1000‐mL blood loss) of red cells would be present postoperatively. Hemodilution and EPO act synergistically to yield additional postoperative red cell volume.CONCLUSION: The use of preoperative EPO with a preoperative increase in Hct results in an increased postoperative Hct after a surgical blood loss. Such a postoperative increase is a function of the volume of blood lost and the patient's blood volume but is independent of the patient's initial Hct. The final postoperative red cell volume increase associated with a preoperative increase in Hct of 1 to 5 percent is limited, however (generally equivalent to a fraction of 1 unit of allogeneic blood). Much of the increase in the patient's Hct vanishes at higher blood losses, and this therapy is most effective with blood loss of >4000 mL. EPO therapy alone may be most effectively used in patients with mild anemia who are undergoing routine surgical procedures that commonly require blood transfusion.
Standardized units of RBCs:Is it time for implementation?
Authors: Högman C.F. , Knutson F. 
Published: March 2003

BACKGROUND: Current practice for the preparation of RBCs from whole blood for transfusion results in poorly standardized contents of RBC Hb. The principle of apheresis, metering the anticoagulant into the collected blood, which is pumped into an empty container, allows variation in the collected volume according to properties of the donor.STUDY DESIGN AND METHODS: The total Hb mass of each person in a representative group of Swedish blood donors was evaluated by using Hb concentration and blood volume (BV), with the latter calculated from each donor's weight and height. The number of blood units that could be collected without exceeding 13 percent of the BV was estimated at a standardized content of RBC Hb set at 40, 45, and 50 g.RESULTS: With Hb standards of 45 and 50 g per unit of RBCs, it would be possible to collect 1 unit, but not more, from 93 female donors in the study; with 40 g of Hb as the standard, 2 units could be collected from 6 percent of the donors. Using a standard of 40 g of Hb, it would be possible to collect 2 units or more from 95 percent of 121 male donors. The corresponding figures at Hb standards of 45 and 50 g were 81 and 50 percent, respectively, of the male donors. The largest number of units that could be collected would thus be obtained at a 40‐g Hb standard. However, the greatest total mass of RBC Hb would have been obtained at 45 g. Even the yield of plasma would reach a maximum at this RBC Hb standard.CONCLUSION: Depending on the donor's Hb and BV, it is possible to collect either 1 or 2 units of RBCs without exceeding 13 percent of any donor's BV, provided the collected volume of blood in each unit is less than the current standard. Such practice would allow better use of the donor population. Two‐unit blood collections may reduce donor exposure in transfusions. Applying a standard at 45 g of RBC Hb per unit was found to permit the collection of maximum RBC Hb and plasma in the evaluated population of Scandinavian donors. Perhaps it is time to discuss a change in current rules for the preparation of RBCs for transfusion.
Longitudinal monitoring of WBC subsets in packed RBC units after filtration: implications for transfusion transmission of infections
Authors: Roback J.D. , Bray R.A. , Hillyer C.D. 
Published: March 2003

BACKGROUND: Specific subsets of peripheral blood WBCs are reservoirs for infectious agents, such as CMV and EBV, and can serve as vectors for transfusion transmission of these agents. While filter WBC reduction has been used to prevent transfusion transmission of infections, its effectiveness has not been documented for many infectious agents and in some instances may be difficult to demonstrate in clinical trials. Because the effectiveness of filtration depends on the number of infected WBCs remaining at transfusion, WBC subpopulations in packed RBC units were quantitated after filtration and storage.STUDY DESIGN AND METHODS: Packed RBC units (n = 14) were filtered and stored at 4oC for 42 days or were stored without filtration. Serial samples were subjected to flow cytometric immunophenotyping of WBC subsets: neutrophils, monocytes, CD4+ and CD8+ T cells, B cells, and NK cells.RESULTS: Filtration produced a mean reduction in total WBCs of 3.2 log. Monocytes, lymphocytes, and neutrophils were reduced by 4.1, 3.8, and 2.5 log, respectively. Lymphocyte subsets also demonstrated differential reduction with filtration. All WBC subsets showed ongoing loss during storage.CONCLUSIONS: Monocyte and lymphocyte subsets are removed most effectively by prestorage filtration. Postfiltration storage leads to further significant reductions in WBC subsets. The implications of these findings for the mitigation of transfusion transmission of infection are discussed.
False‐negative testing errors in routine viral marker screening of blood donors
Authors: Busch M.P. , Watanabe K.K. , Smith J.W. , Hermansen S.W. , Thomson R.A. ,   for the Retrovirus Epidemiology Donor Study
Published: March 2003

BACKGROUND: The contribution of testing errors to the risk of virus transmission by transfusion depends on the rate of false‐negative testing errors and the prevalence of infected seropositive donations. Although the false‐negative testing error rate has been estimated at 0.1 to 1 percent on the basis of proficiency studies, it has not previously been measured in routine donor screening.STUDY DESIGN AND METHODS: A 1991 to 1995 database containing 5,153,153 donations from 1.5 x 106 donors (including autologous donors) was searched to identify donors who tested seropositive for HIV, HCV, HTLV‐I or II and who attempted subsequent donations. The false‐negative rate in routinely screened follow‐up donations was determined, and false‐negative cases were investigated to identify the cause.RESULTS: Subsequent donations (n = 2015) by 1224 donors with confirmed‐positive results were identified. Eleven (0.5%) of these donations did not react in EIA. Ten of the 11 false‐negative cases were attributable to borderline‐reactive donations. On subsequent donations, there were borderline‐nonreactive results on HTLV‐I (2 cases), first‐generation HCV (5 cases), and second‐generation HCV (3 cases) EIAs. The final case was strongly reactive for HCV in a second‐generation EIA on two donations (signal‐to‐cutoff [S:C] ratio >3.5), followed by a baseline nonreactive result on a third donation (S:C = 0.05).CONCLUSION: False‐negative testing results occur infrequently during routine infectious‐disease donor screening. Although most false‐negative results occurred with borderline‐reactive HTLV‐II samples and/or early‐generation HCV EIAs, frank technical errors (e.g., sample mixup or failure to add sample to EIA well) also occur at a low rate (0.05%; 95% CI, 0‐1.5%). Process enhancements designed to reduce errors (e.g., enhanced automation of data management and testing systems and process controls for EIAs) are warranted to detect and prevent false‐negative results.