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Background and Objectives Bacterial contamination represents the major infectious hazard associated with transfusion of platelet concentrates ( PCs). As bacterial screening of PCs is not mandatory in Germany, the Bacti Flow flow cytometry test has been introduced as a rapid detection method to increase product safety. Materials and Methods During a period of 25 months, a total of 34 631 PCs (26 411 pooled and 8220 apheresis-derived PCs) were tested at the end of day 3 of their shelf life using the Bacti Flow system. PCs initially reactive in Bacti Flow testing and expired PCs not reactive in Bacti Flow on day 3 were also investigated by the Bac T/ ALERT system and by microbiological cultivation in order to identify the contaminating bacterial species and to confirm reactive Bacti Flow results. Results Two hundred and twenty-eight PCs (0·7%) had an initially reactive result, 24 of them remained reactive in a second test run. Out of these reproducible reactive Bacti Flow results, 12 could not be verified by parallel Bac T/ ALERT culturing, resulting in a confirmed false-positive rate of 0·03%. The bacterial species were identified as S. aureus, S. epidermidis, S. dysgalactiae ssp. equisimilis and B. cereus. In 10 out of 9017 expired PCs (0·11%), a confirmed-positive result was obtained in the Bac T/ ALERT system which had a negative result in the Bacti Flow system. Conclusion Testing of PCs by Bacti Flow was successfully implemented in our blood donation service and proved sufficient as a rapid and reliable screening method. False reactive results are in an acceptable range since the transfusion of 12 bacterially contaminated PCs was prevented. [ABSTRACT FROM AUTHOR]

Background Due to the ageing population, blood donation by the elderly is necessary to maintain blood supply. We initiated a prospective study, to assess whether there is an increased risk of donor reactions in elderly donors. Study Design and Methods In this prospective study, regular donors aged from 66 to 68 and 69 to 71 years were invited to continue blood donation on mobile collection sites of the German Red Cross Blood Service West. A control group (50-52 years) was established. Admission of donors in all groups followed the German national guidelines for blood donation. Donor deferrals and all kinds of donor reactions during donation (on-site) and in the 48 h following donation (off-site) were monitored. Results A total of 64 260 valid cases were entered in the study. Donor deferrals increased with age from 1·12% in the control group up to 8·74 in female donors aged 69-71 years. Adverse reactions to blood donation were rare with an overall reaction rate of 0·63% (0·05% on-site; 0·58% off-site). Off-site reactions significantly decreased with increasing age. The relative risk (RR) for adverse reactions in elderly donors compared to the control group (50-52 years) was slightly increased for on-site reactions in the 69- to 71-year-old donors (RR 1·0309; 95% CI 1·0292-1·0325). In all other comparisons, the RR for adverse reactions was distinctively lower in elderly donors (RR 0·3785 - 0·7778). Conclusions Our data confirm that elderly regular blood donors may safely continue blood donation at least to the age of 71. Based on these data, we increased the upper age limit. [ABSTRACT FROM AUTHOR]

The origin of HLA class I molecules on platelets is still under discussion. Adsorption of HLA molecules on platelets using specific experimental conditions has been described. The study presented investigates whether there is a significant elution and adsorption of HLA class I molecules on platelets during storage of pooled random platelet concentrates (PRPC) under routine conditions. Platelet concentrates (PCs) from whole blood were prepared from HLA-A2-positive and HLA-A2-negative donors, pooled and stored under routine conditions. In addition, platelets from HLA-A2-negative donors were pelleted and resuspended in cell-free plasma from HLA-A2-positive donors. HLA-A2-positive PCs (positive control), HLA-A2-negative PCs (negative control) and HLA-A2-negative platelets in plasma from HLA-A2-negative donors were stored simultaneously. Binding of FITC-conjugated monoclonal murine antihuman HLA-A2 antibodies (anti-HLA-A2-mab) was measured during 5-day storage by flow cytometry. An increased binding of anti-HLA-A2-mab during storage was found on HLA-A2-negative platelets ( P < 0·005) independently whether they were incubated with cell-free plasma or platelets from HLA-A2-positive donors or autologous HLA-A2-negative cell-free plasma. However, non-specific binding of IgG controls increased equally, whereas anti-HLA-A2-mab binding to platelets from HLA-A2-positive donors did not decrease during storage. This study suggests that there is no significant elution and adsorption of HLA class I antigens of platelets in pooled PCs during storage under the usual conditions for platelet storage. Increased anti-HLA-A2-mab signal was due to non-specific binding. Therefore, HLA class I compatible platelets should maintain their compatibility for an immunized patient when stored in a pool with HLA incompatible platelets and shortened survival after transfusion should not be expected. [ABSTRACT FROM AUTHOR]

Summary Background Provocation tests are invaluable in establishing threshold levels and a causal relationship between atopic asthma and a certain allergen source, especially in relation to work-associated exposure. Purified major allergens open possibilities for a more accurate assessment of sensitization. Objective To determine the threshold dose of purified major bovine dander allergen Bos d 2 in bronchial provocation in comparison with the standard allergen and a set of other parameters of allergy. Method Nine consecutive patients referred to hospital for confirming the bovine origin of their occupational asthma were subjected to bronchial provocation tests with purified natural Bos d 2 and a standard bovine dander allergen. Additional tests included bronchial histamine challenge, measurements of total IgE, specific IgE antibody determinations and skin prick tests (SPT) with both allergens. Results In the provocation tests with Bos d 2, a 15% decrease in the forced expiratory volume in 1 s (FEV1 ) and/or peak expiratory flow (PEF) values in eight out of nine patients confirmed the predominant role of Bos d 2 in the sensitization. The threshold dose of Bos d 2 varied from 0.1 µg to > 100 µg (median ± median absolute deviation = 4.5 ± 3.9 µg). A positive SPT was induced by a median dose of 13.9 ± 9.8 µg of Bos d 2. Bronchial response to histamine and IgE antibodies against Bos d 2 showed the highest correlations to the provocations results. Conclusions The efficacy of Bos d 2 in bronchial provocation in patients with occupational cattle-associated asthma was confirmed and the range of the threshold level was determined. There were individual variations, but the response in provocation remains the reference method for identification of the cause of occupational atopic asthma. SPT and the measurement of specific IgE antibodies, preferably with purified or recombinant major allergens, increase the accuracy of the... [ABSTRACT FROM AUTHOR]

Background About one in every four cases of occupational rhinitis recorded in Finland is animal-induced. Bovine allergens are the most important in this respect and the largest patient group consists of dairy farmers. Allergen immunotherapy, if proven effective, safe and feasible, would be ideal for their treatment. The development of recombinant allergens has offered new potential therapeutic prospects. Fragments of recombinant Bos domesticus (Bos d 2) allergen could be suitable for this purpose because they are recognized by T cells but their IgE-binding capacity is attenuated. Objective The aim of this study was to verify whether the potential of the two fragments of recombinant Bos d 2 (corresponding to amino acids 1–131 and 81–172) to induce immediate allergic reaction in a shock organ (nose) was decreased compared to the complete recombinant allergen, which would be an advantageous property for a preparation intended for allergen immunotherapy. Methods The study group consisted of 10 dairy farmers with cow-induced allergic rhinitis. We used the IgE titres against native Bos d 2 measured by indirect IgE ELISA to characterize the level of sensitization and compared the IgE titres in the rhinitis patients with 12 cow-sensitized asthmatic farmers and 12 healthy students. In vitro reactivity against recombinant Bos d 2 and its two fragments was studied by indirect IgE ELISA and in vivo reactivity by nasal provocation tests. Results The IgE titres against native Bos d 2 of patients with rhinitis tended to be lower than the titres of asthmatics. The healthy students did not exhibit any detectable IgE reactivity to native Bos d 2. In the patients with rhinitis, there was no statistically significant difference between IgE responses against native and recombinant Bos d 2, whereas with both in vitro and in vivo, the reactivity to both fragments of recombinant Bos d 2 was lower than the reactivity to the complete recombinant allergen. Conclusions Due to the decreased in vivo capacity to induce immediate allergic reactions, the fragments may be better tolerated in allergen immunotherapy than the complete allergen. [ABSTRACT FROM AUTHOR]

Background: In cases of warm autoimmune hemolytic anemia (WAIHA), crossmatch incompatible RBCs are most often used for transfusion. The determination of the in vivo survival of transfused and autologous RBCs in WAIHA is helpful in the assessment of the efficacy of transfusion and other therapeutic interventions.Case Report: A 38-year-old man presented with acute WAIHA, thrombocytopenia, and neutropenia. Steroids and IVIG therapy were ineffective, and the patient received RBCS: Because of increasing hemolysis and persisting thrombocytopenia, splenectomy was performed, resulting in partial remission. Further improvement was achieved by immunosuppressive therapy.Materials and Methods and Results: Survival of transfused and autologous RBCs was determined, using a flow cytometric method based on the determination of different blood group antigens of patient and donor RBCS: The survival of autologous and transfused RBCs before splenectomy was determined on two consecutive days. The life span of autologous RBCs remained rather stable at 69 and 64 hours on Days 10 and 11, respectively, whereas the life span of transfused RBCs decreased from 186 hours to 25 hours. After splenectomy, the life span of transfused RBCs almost normalized: 43 days at postsplenectomy Day 3 and 87 days at postsplenectomy Day 69.Conclusion: Flow cytometry was successfully used to determine changing hemolytic activity during the clinical course of WAIHA. Additionally, the survival of transfused RBCs could be measured, which may be helpful to judge for the compatibility of allogeneic RBCS: Thus, we were able to show the therapeutic inefficacy of steroids and immunoglobulins, and quick improvement after splenectomy. [ABSTRACT FROM AUTHOR]

Describes the manual backup system (MBS) for maintaining the delivery of blood supply during computer network breakdown. Lack of delay in issue of blood products or result reporting; Duplication of patient data, requesting ward and ordered test through a from the request forms on MBS worksheets; Documentation of a 90-min breakdown period.

Background Cow dust is one of the most important inducers of occupational allergic diseases in Finland. For example, in 1991 it accounted for almost 40% of the new occupational asthma cases. Objective This study compares the performance of the purified major cow allergen (BDA20) and crude bovine epithelial extract (BEA) in diagnostic tests and examines the role of milk allergy-associated bovine proteins (bovine scrum albumin, α-lactalbumin, β-lactoglobulin, casein) in respiratory cow allergy. Methods The humoral responses of cow-asthmatic and healthy farmers to the various components of BFA were analysed with sodium dodecyl sulfate-polyacralamide gel electrophoresis (SDS-PAGE) and immunoblotting. The levels of specific IgE and IgG antibodies were quantificated with enzyme-linked immunosorbent assays (ELISAs). The cellular responses were analysed with antigen-specific lymphocyte proliferation tests. Results The specific anti-BDA20 IgE measurement was found to be best in distinguishing between the asthmatic farmers and their healthy colleagues. It proved possible to determine a cut-off value that gave the analysis a specificity and sensitivity of 100% the distinction between the two groups was highly significant (P< 0.0001). In the lymphocyte proliferation analysis, cow asthma was more closely associated with reactivity to BDA20 than to BEA. In the measurement of anti-BDA20 and anti-BEA IgG antibody levels, considerable overlap between the groups was observed, suggesting that these antibodies are not directly involved in cow allergy. When proteins associated with milk allergy were used as test reagents, no statistically significant differences could be observed between the groups, except for anti-casein IgE antibodies the level of which, however, overlapped considerably between the farmer groups. Conclusion These findings suggest that purified BDA20 is better than BEA for diagnosing cow asthma and that proteins associated with milk allergy are of only marginal significance in this disease. [ABSTRACT FROM AUTHOR]

A letter to the editor related to anti-hepatitis B testing of blood donors published in a previous 2006 issue is presented.

Examines the effect of virus inactivation on coagulation factors in therapeutic plasma. Result of methylene blue (MB) virus inactivation; Factors that lead to a decrease in coagulation activity; Test of human plasmas inactivated with MB phototreatment or solvent detergent treatment in a series of in vitro coagulation assays.