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A Shanwell

Publications and source records attributed to A Shanwell.

At least 19 recordsLinked to original sources
PubMed2006

A population-based binational register for monitoring long-term outcome and possible disease concordance among blood donors and recipients.

BACKGROUND AND OBJECTIVES: Even with appropriate donor deferrals and advanced screening tests, the risk of disease transmission through blood transfusion cannot be completely disregarded. Efficient monitoring of possible disease transmission between blood donors and recipients should be an important component of a comprehensive haemovigilance system. MATERIALS AND METHODS: We assembled the Scandinavian Donations and Transfusions (SCANDAT) database, with data on virtually all blood donors and recipients who have been registered at least once in any of the computerized local blood bank databases in Sweden and Denmark since the start of computerized registration in 1966. The records of these individuals, with their entire computerized donation and/or transfusion histories and all donor-component-recipient connections, were linked to nationwide population and health registers to attain essentially complete follow-up for up to 36 years regarding reproduction, hospital morbidity, cancer, and death. RESULTS: After data cleaning, the database contained 1,134,290 blood donors who contributed 15,091,280 records of donations and 1,311,079 recipients who received 11,693,844 transfusions. The data quality in the existing data sources was satisfactory. From the data obtained from local blood banks, 4.6%, 1.6%, and 6.4% of the person, donation, and transfusion records, respectively, had to be discarded after review of the legitimacy of recorded values, and comparisons with independent, external databases. CONCLUSION: It is possible to use existing computerized data, collected in routine health care, in haemovigilance systems for monitoring long-term outcome and disease concordance in blood donors and transfusion recipients.

Blood Donors↗
PubMed2005

Refractory acute renal allograft rejection successfully treated with photopheresis.

INTRODUCTION: Acute rejection episodes still occur in spite of modern immunosuppressive protocols. We present seven patients with biopsy-proven acute rejections after kidney transplantation refractory to repeated pulses of high-dose steroids and antithymocyte globulin (ATG) or OKT-3, but responsive to photopheresis therapy. METHODS: Photopheresis is a nontoxic immunomodulatory, apheresis-based treatment with no general immunosuppressive action. Rather, it suppresses specific pathogenic T-cell clones. During photopheresis mononuclear leukocytes are collected from the patient using centrifugation technique, treated with a photosensitizing agent, irradiated, and subsequently retransfused. RESULTS: All patients tolerated the treatment well, with no notable side effects. At the 12-month follow-up the median creatinine had decreased to 161 mumol/L compared to 282 mumol/L at the start of photopheresis and at the last follow-up 12 to 43 months after transplantation all patients still had functioning grafts. In five of the seven cases there had been a significant improvement in renal function, whereas in two of the patients the renal function remained stable but without a decrease in creatinine. CONCLUSIONS: It is our experience that the prognosis for renal allografts with acute rejection unresponsive to conventional antirejection treatment (ie, repeated pulses of methylprednisolone and ATG or OKT-3) is very poor. Therefore, we conclude that the photopheresis treatment contributed to the favorable outcome in this small group of patients. We are presently designing a prospective randomized study to further evaluate the effect of photopheresis after renal transplantation.

Acute Disease↗
PubMed2003

Storage of platelets in additive solutions: the effects of magnesium and potassium on the release of RANTES, beta-thromboglobulin, platelet factor 4 and interleukin-7, during storage.

BACKGROUND AND OBJECTIVES: Several studies have suggested that the accumulation of cytokines during storage of platelet concentrates may mediate non-haemolytic transfusion reactions. Prestorage leucodepletion can prevent the release of cytokines from white blood cells during storage, but not the release of platelet-derived cytokines. Therefore, we investigated whether the addition of magnesium and potassium to platelets stored in a platelet additive solution (PAS) would affect the generation of cytokines during platelet storage. MATERIALS AND METHODS: Platelets were prepared from buffy coats using different suspension media: plasma; 70% PAS-III + 30% plasma; 70% PAS-III supplemented with magnesium and potassium +30% plasma; and 80% PAS-III supplemented with magnesium and potassium +20% plasma. The levels of certain cytokines--regulated on activation, normal, T-cell expressed, and secreted (RANTES), beta-thromboglobulin (beta-TG), platelet factor 4 (PF4) and interleukin-7 (IL-7)--were measured by enzyme-linked immunosorbent assay (ELISA) on days 1, 5 and 7. RESULTS: The concentrations of RANTES, beta-TG, PF4 and IL-7 increased, during storage, in all units. The increase was significantly greater in units stored in 70% PAS-III +30% plasma than in the other three suspension media. The storage of platelets in 70% PAS-III supplemented with magnesium and potassium +30% plasma significantly reduced the concentrations of platelet derived-cytokines during storage, as compared to platelets stored in 70% PAS-III + 30% plasma alone. CONCLUSIONS: The concentrations of platelet-derived cytokines increased, to a significantly greater extent, when platelets were stored in PAS-III than in plasma. However, when magnesium and potassium were added to PAS-III, the concentrations of platelet-derived cytokines obtained during storage were about the same as those produced by platelets stored in plasma.

Blood Platelets↗
PubMed2001

Long-term survival in transfusion recipients in Sweden, 1993.

BACKGROUND: Survival and characteristics of transfusion recipients have not been studied enough, although they represent key measures in cost-effectiveness analyses of various donor screening procedures. STUDY DESIGN AND METHODS: Hospital and blood bank records were collected on all patients in Orebro County, Sweden, from March through May 1993 (1111 transfusion episodes) and a random sample from Stockholm County during April 1993 (793 transfusion episodes). All patients were then matched with the national register of deaths in Sweden during a follow-up period of 40 months. RESULTS: The median patient age was 71 years and the median transfusion total was 2 units. Only 35 percent of the patients were under the age of 65, 9 percent under 40, and 1.6 percent under 1 year. About half (56%) were women. Among the Orebro patients, 47 percent were surgical and 29 percent internal medicine patients. Of 1720 patients whose survival could be investigated, 66 percent were alive after 1 year and 51 percent after 40 months. The survival rates were rather similar in patients receiving RBCs and plasma but lower in those receiving platelets. CONCLUSION: The survival of patients transfused in Sweden in 1993 differered significantly from estimations based on studies from the 1980s. This difference has major implications for the estimations of cost-effectiveness of blood donor screening for infectious agents.

Aged↗
PubMed2001

K, Fy(a), and Jk(a) phenotyping of donor RBCs on microplates.

BACKGROUND: In many cases, the search for compatible blood for patients with clinically significant RBC alloantibodies is difficult and time-consuming. To date, it has been considered necessary only to phenotype the blood donors for ABO group and D. There has been long experience with automated routine analysis (ABO, C, c, D, E, and e typing and RBC antibody screening), using robotic dispensers and computerized interpretation of microplate results. The purpose of this study was to explore the possibilities of also phenotyping for K, Fy(a), and Jk(a), as antibodies directed against these antigens (together with Rh antigens) are the most common clinically significant alloantibodies in the Swedish population. STUDY DESIGN AND METHODS: One thousand thirty-one EDTA samples from blood donors were phenotyped for K, Fy(a), and Jk(a) by use of an IAT with PEG on microplates. The findings were compared to those using conventional IAT in tube's and the microcolumn gel test (DiaMed-ID, DiaMed). RESULTS: All typing results with the microplate method were correct. All reactions for K and Fy(a) typing could be interpreted by the computer. The results for Jk(a) were indeterminate in 1.4 percent (14/1031) of the samples. CONCLUSION: The PEG-IAT microplate method gave reliable results that were suitable for routine phenotyping, thus making available a stock of phenotyped blood at reasonable cost, ready for delivery when required.

Blood Donors↗
PubMed2000

[A case of neonatal ABO immunization which was difficult to diagnose. The mother with blood group A2 and the infant with negative direct antiglobulin test].

In caucasians, in about 15 percent of all pregnancies the mother has blood group O and the child blood group A or B which is the usual setting in cases of HDN due to ABO-incompatibility. We describe a case of HDN where the mother had blood group A2 and no irregular erythrocyte antibodies. The patient, who was born at full term, had blood group A2B and negative DAT (Direct Antiglobulin Test). At 36 hours of age exchange transfusion was performed due to a serum bilirubin level of 340 (< 150) mumol/l. The mother had high titres of anti-B antibodies of IgG type and elution indicated presence of anti-B antibodies on the child's erythrocytes.

ABO Blood-Group System↗
PubMed2000

Storage of platelets in additive solutions: effects of phosphate.

BACKGROUND AND OBJECTIVES: In a previous study, low adenine nucleotide levels and a reduced rate of glycolysis were found in platelet concentrates (PCs) prepared by apheresis and stored in a platelet additive solution (PAS). Our objective was to investigate whether the use of PAS with or without phosphate can influence platelet metabolism in a similar way. MATERIALS AND METHODS: The in vitro effects of storage in either plasma or a PAS (T-Sol or PAS-III, both containing citrate, acetate and sodium chloride, PAS-III containing also phosphate) of buffy-coat-derived pooled platelet concentrates (BC-PCs) and apheresis platelets were investigated. The use of PAS implies inclusion of some plasma (20 or 35%). Paired studies over 7 days included investigation of cell counts, pH, PO2, PCO2, bicarbonate, glucose, lactate, adenine nucleotides, and extracellular adenylate kinase activity as a marker for disintegration of platelets. The expected concentration of phosphate in T-Sol is 0.6-1.8 mmol/l (with CPD plasma) and 0.2-0.6 mmol/l (with ACD plasma), and in PAS-III, 15-25 mmol/l (calculated values). RESULTS: BC-PCs were compared during storage in 35% CPD plasma and 65% PAS (T-Sol or PAS-III) (experiment 1), or alternatively 20% CPD plasma and 80% PAS (T-Sol or PAS-III) (experiment 3). In both studies, PAS-III shows similar and significantly higher rates of glycolysis in terms of consumption of glucose (0.06 vs. 0.04 mmol/day/10(11) platelets) and production of lactate (0.11 vs. 0.07 mmol/day/10(11) platelets) compared with T-Sol. Levels of pH and adenine nucleotides were similar when 35% plasma was used. With only 20% plasma, significantly higher levels of adenine nucleotides were found with PAS-III compared to T-Sol. The storage of apheresis platelets in 35% ACD plasma and 65% PAS (either T-Sol or PAS-III) (experiment 5) gave significantly higher values for PAS-III compared to T-Sol with regard to consumption of glucose (0.08 vs. 0.06 mmol/day/10(11) platelets), production of lactate (0.14 vs. 0.11 mmol/day/10(11) platelets) and adenine nucleotide levels. CONCLUSION: With respect to apheresis PCs stored in media containing ACD plasma, our results suggest that the differences found are related to the concentration of phosphate. The results for BC-PCs stored in media containing CPD plasma suggest that PAS-III is preferable to T-Sol as the PAS at plasma concentrations below 35%. The mechanism behind the phenomena observed with BC-PCs is not known.

Blood Platelets↗
PubMed1999

Clinical evaluation of a solid-phase test for red cell antibody screening of pregnant women.

BACKGROUND: The aims of this study were to evaluate the results of a new solid-phase screening test for detecting atypical red cell (RBC) antibodies in a large number of pregnant women and to compare these results to the clinical outcome of the newborn. STUDY DESIGN AND METHODS: A total of 38,700 infants born in Stockholm were studied retrospectively. Of these infants, 18,500 were born to pregnant women screened with the solid-phase test. Data were collected on all newborns with a positive direct antiglobulin test (DAT) and on infants requiring an exchange transfusion or a blood transfusion. These data were correlated to the screening results for the mothers. RESULTS: Of 409 DAT-positive newborns, a serologic explanation for the positive DAT was found in 349. Three hundred four cases were due to ABO incompatibility between mother and child; 19 of these infants needed an exchange transfusion. Forty-two cases were due to unexpected maternal RBC antibodies; 11 of these infants were given an exchange transfusion. All 11 were identified before birth. Three other infants had DAT-positive tests due to ABO incompatibility and to unexpected maternal RBC antibodies. CONCLUSION: ABO incompatibility is a major indication for exchange transfusion in DAT-positive newborns. There was no evidence that the solid-phase screening test had failed to detect any clinically significant RBC antibodies. Finally, the results of this study do not indicate a need for routine screening of D+ women more than once during each pregnancy.

ABO Blood-Group System↗
PubMed1998

[Successively improved prognosis in erythrocyte immunization].

Prognosis in cases of erythrocyte immunisation has improved continuously over the past decades. Morbidity and mortality have been reduced by improvements in management, including screening programmes, non-invasive ultrasound evaluation and invasive procedures. The article provides an outline of the latest developments in the management of erythrocyte immunisation, and several controversial issues are discussed, such as antibody screening, strategies for the reduction of antibody titres, and the organisation of care.

Anemia, Neonatal↗
PubMed1998

Screening for human T cell leukaemia/lymphoma virus among blood donors in Sweden: cost effectiveness analysis.

OBJECTIVE: To analyse the cost effectiveness of a national programme to screen blood donors for infection with the human T cell leukaemia/lymphoma virus. DESIGN: Three models for calculating the costs and benefits of screening were developed. The first model analysed the cost of continuously testing all donations; the second analysed the cost of initially testing new blood donors and then retesting them after five years; the third analysed the cost of testing donors only at the time of their first donation. Patients who had received blood components from donors confirmed to be infected with the virus were offered testing. SETTING: Sweden. MAIN OUTCOME MEASURES: Prevalence of infection with the virus among blood donors, the risk of transmission of the virus, screening costs, and the outcome of infection. RESULTS: 648 497 donations were tested for the virus; 1625 samples tested positive by enzyme linked immunosorbent assay. 6 were confirmed positive by western blotting. The prevalence of infection with the virus was 2/100 000 donors. 35 patients who had received blood infected with the virus were tested; 3 were positive. The cost of testing every donation was calculated to be $3.02m (1.88m pounds); this is 18 times higher than the cost of testing new donors only, and only 1 additional positive donor would be discovered in 7 years. Regardless of the model used, screening was estimated to prevent only 1 death every 200 years at a minimum cost of $36m (22.5m pounds). CONCLUSION: Based on these estimates the Swedish National Board of Health and Welfare decided that only new blood donors would be screened for infection with the virus.

Adult↗
PubMed1997

A system for the supply of platelets suspended in a storage medium including buffy-coat-derived platelet concentrates in combination with "split" apheresis platelets.

Our objective was to create a system for the supply of platelet concentrates (PCs) based on leukocyte-filtered PCs suspended in a storage medium (PAS-II) including: (1) pooled buffy-coat-derived (BC) PCs and (2) "split" apheresis PCs. The same standards were intended for the two preparations with regard to composition and blood cell counts. In preliminary studies, similar in vitro data were found for leukocyte-filtered and non-filtered reference BC PCs. Slightly inferior in vitro results than for BC PCs restricted the shelf-life of apheresis PCs to 5 days compared to 7 days for BC PCs. With the present platelet supply system in use as a routine service for one year, the experience was very satisfactory, meeting the demands for PCs very efficiently and resulting in a low out-dating rate (5%).

Blood Platelets↗
PubMed1997

Generation of cytokines in red cell concentrates during storage is prevented by prestorage white cell reduction.

BACKGROUND: The effect of prestorage white cell (WBC) filtration on the cytokine content in red cells (RBCs) has not been clarified. STUDY DESIGN AND METHODS: Six units of buffy coat-poor RBC concentrates were prepared. Each unit was divided into three parts: one was used as a control, the second was made WBC-rich by the addition of WBCs from the buffy coat, and the third was made WBC-poor by filtration. All units were stored at 4 degrees C for 6 weeks. Immediately after preparation and every second week subsequently, samples for analyses of interleukin (IL) 1 beta (IL-1), IL-2, IL-6, IL-8, and tumor necrosis factor alpha (TNF alpha) were obtained. After 13 weeks, the procedure was repeated on the same donors. RESULTS: IL-2 was not detected. The amounts of IL-1, IL-8, and TNF alpha increased during the storage period. With the exception of IL-8, only low concentrations were found. Filtered units had lower concentrations of IL-1, IL-6, IL-8, and TNF alpha after 2 weeks of storage than did the control and WBC-rich units. The amounts of cytokines in filtered units did not increase during the study period. CONCLUSION: Prestorage filtration seems to diminish the amount of IL-1, IL-6, IL-8, and TNF alpha RBCs during storage. The possible clinical implications of this should be elucidated.

Adult↗
PubMed1996

Evaluation of a solid-phase test for erythrocyte antibody screening of pregnant women, patients and blood donors.

UNLABELLED: We have studied a previously described solid-phase test (SPH) for screening and identification of antibodies directed against erythrocyte antigens, in large sample numbers and throughout routine processing. The screening results of all samples from pregnant women, patients and blood donors (n = 36,701) sent to our blood bank from August 1992 to July 1993 were compiled and evaluated. Pregnant women were screened by the SPH-antiglobulin technique (IAT) and the SPH-enzyme-enhanced technique (ENZ), while the patients and blood donors were screened only by the SPH-IAT. Samples with known alloimmunization were excluded from this study. Positive screening reactions were further investigated by the SPH-IAT and SPH-ENZ techniques, the manual hemagglutination tests low ionic-strength solution IAT and 2-stage papain. Pregnant women: A positive reaction in one or both of the SPH tests was found in 1.2% of the samples. The SPH tests identified 99 (98.0%) and the manual methods 79 (78.2%) of a total of 101 antibodies. Of the identified antibodies, 61 were to antigens in the Rh blood group system, including 34 Rh immune globulin. The remainder had specificity directed against antigens K, Jka, M, S, Le(a) and Le(b). PATIENTS: A positive reaction in the SPH-IAT test occurred in 0.9% of the samples. The antibodies identified had specificity directed against antigens D, C, c and E in the Rh blood group system. The remainder had specificity directed against antigens Fya, K, Jka, M and Le(a). All antibodies identified by SPH-IAT, except 1 anti-M and 2 anti-Le(a), were also identified by manual methods. Blood donors: A positive reaction in the SPH-IAT test was noted in 0.7% of the samples. The identified antibodies had specificity directed against antigens D, C, E, Fya, K and M. All antibodies identified by the SPH-IAT, except 1 anti-D found in a sample from an RhD(+) male, were also identified by the manual methods. This study indicates that the SPH-IAT test is sensitive for detecting anti-M. This was also indicated for the SPH-ENZ test concerning the Jka antibody. An advantage of using solid-phase antibody screening tests for a larger series of samples is the possibility of automated sample identification, dilution, dispensing and interpretation of results. The SPH-IAT and the SPH-ENZ tests permitted us to select test cells, preferably from our own donor pool. We conclude that the SPH-IAT and SPH-ENZ tests are suitable for routine antibody screening of pregnant women and the SPH-IAT test for screening patients and blood donors.

Antigens↗
PubMed1996

Flow cytometric quantitation of serum anti-D in pregnancy.

BACKGROUND: The major cause of fetal hemolytic disease is maternal immunization to D in D-incompatible pregnancies. To prevent complications, D-incompatible pregnancies are monitored for the level of maternal anti-D. At present, the monitoring of anti-D levels is performed by the indirect antiglobulin test complemented by quantitation by the technique used in an automated antibody detection and quantitation instrument. STUDY DESIGN AND METHODS: Flow cytometry was used to quantitatively determine the level of anti-D in serum and to analyze the IgG subclass distribution and the presence of IgM anti-D in these samples. The results were compared to the indirect antiglobulin test titer and to the results obtained by the technique used in an automated antibody detection and quantitation instrument. RESULTS: Flow cytometry allowed sensitive and accurate determinations of anti-D levels with low interassay and intra-assay variability, both for serum samples and standard curves. CONCLUSION: Flow cytometry is a simple, rapid, and reliable method for determining the serum levels of D antibodies and their Ig subclass distribution. It is therefore well suited for the monitoring of women during D-incompatible pregnancies.

Female↗
PubMed1996

Prestorage versus bedside white blood cell filtration of red blood cell concentrates: effects on the content of cytokines and soluble tumor necrosis factor receptors.

BACKGROUND: The cytokine network has important implications for the systemic inflammatory and metabolic response in trauma and infection. The objective of this study was to investigate the influence of white blood cell (WBC) filtration on the cytokine content in red blood cell concentrates (RBCs). STUDY DESIGN AND METHODS: Tumor necrosis factor-alpha (TNF), interleukin-1-beta (IL-1), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-10 (IL-10), and soluble TNF receptors I and II (sTNF-RI, sTNF-RII) were investigated in filtered and nonfiltered RBCs during storage. After 40 days of storage the originally nonfiltered units were filtered. RESULTS: On day 1 prestorage filtered RBCs had lower concentrations of WBCs (p < 0.001), TNF (p < 0.01), sTNF-RI (p < 0.01) and sTNF-RII (p < 0.05) compared to nonfiltered units. IL-1 concentrations increased from day 1 to day 40 (p < 0.05) in nonfiltered RBCs and were higher in nonfiltered units compared to prestorage filtered ones on day 40 (p < 0.05). An increase of IL-8 was found in nonfiltered RBCs as well as prestorage filtered units from day 1 to day 40 (p < 0.05) but the concentrations of IL-8 were higher in nonfiltered units on day 40 compared to prestorage filtered units (p < 0.05). Filtration at the end of the 40-day storage period had no influence on the concentrations of cytokines and soluble TNF receptors. CONCLUSION: The present results suggest that prestorage WBC filtration may be more efficient in reducing the cytokine content of RBCs compared to filtration at the the end of the storage period. The clinical impact of passive transfer of components of the cytokine network via RBCs, e.g., in critically ill patients, is however unclear and needs further investigations.

Adult↗