Bacterial contamination of platelet concentrates prepared by different methods: results of standardized sterility testing in Germany.
G Walther-Wenke, R Doerner, Th Montag, O Greiss, B Hornei, R Knels, J Strobel, P Volkers, W Däubener
Institute of Transfusion Medicine, Red Cross Donor Service West, Münster, Germany.
Background and Objectives National guidelines for monitoring the bacterial contamination rate of blood components were introduced in Germany in 1997. The objective of this study was to present and evaluate the results of sterility testing of platelet concentrates (PCs) prepared by different methods. Materials and Methods The analysis of results of sterility testing of blood component production from transfusion medicine centres in Germany in 1998 and 2001 was based on information collected using standardized questionnaires. Results The bacterial contamination rates for single-donor PCs derived from whole blood and apheresis (0.210% vs. 0.156%) were comparable and showed no significant difference. However, pooled PCs produced from four buffy coats using the sterile docking procedure showed a significantly higher bacterial contamination rate compared with single-donor PCs derived from whole blood and apheresis (0.184% vs. 0.604%). Conclusions Use of standardized methods for sterility monitoring is sufficient to assess collection and production processes in terms of hygiene and yields reliable data on bacterial contamination rates of blood components. The methods described are suitable for using to analyse the efficiency of newly introduced methods to reduce bacterial contamination rates of blood components (e.g. diversion, bacteria screening and pathogen inactivation).
Bacterial contamination of platelet components: potential solutions to prevent transfusion-related sepsis.
Medical Affairs, Cerus Corporation, Concord, CA, USA. email@example.com
Bacterial contamination of platelet components (PC) is the most prevalent risk for transfusion-transmitted infection. Based on the recent studies with optimal culture methods of expired PC, the prevalence of bacterial contamination is estimated to occur in approximately one in 750 to one in 1000 PC. Only within the last few years have the magnitude of the risks and the range of clinical outcomes associated with bacterial contamination been extensively characterized. Despite increased recognition of bacterial contamination of PC, transfusion-related sepsis is infrequently reported. This has largely been attributed to passive reporting systems, and low levels of clinical awareness for transfusion-related sepsis by primary care physicians. The risk for transfusion of contaminated PC has generally been characterized per component. Importantly, because patients require repeated transfusions of PC during a period of transfusion-dependent thrombocytopenia, it is appropriate to express the risk to receive a contaminated PC on a patient exposure basis. Assuming that the average hematology oncology patient may receive seven PC during a 28-day period of support, the risk of exposure to a contaminated PC is in the range of one in 150 per patient. This level of risk would not be acceptable for other intravenous medications. With increased appreciation of the risk of bacterial contamination, methods were developed to limit the risk of transfusion-transmitted bacteremia. This article focuses on those interventions that have been implemented in routine practice. The most important methods employed to mitigate the risk are improved skin disinfection, initial blood draw diversion, bacterial detection and pathogen inactivation/reduction. These technologies are now undergoing increased use in the clinical practice of transfusion medicine. With increased use, additional data are being generated to more fully characterize the effects of these interventions. Improved disinfection, blood diversion and bacterial detection have decreased, but not resolved the risk of bacterial contamination. Pathogen inactivation/reduction offers the potential for a further substantial decrease of the risk for transfusion of PC contaminated with bacteria.
German Red Cross Blood Service NSTOB, Institute Springe, Germany.
Besides the current efforts devoted to microbial risk reduction, pathogen inactivation technologies promise reduction of the residual risk of known and emerging infectious agents. A novel pathogen reduction process for platelets, the THERAFLEX UV-Platelets system, has been developed and is under clinical evaluation for its efficacy and safety. In addition, proof of principle has been shown for UVC treatment of plasma units. The pathogen reduction process is based on application of UVC light of a specific wavelength (254 nm) combined with intense agitation of the blood units to ensure a uniform treatment of all blood compartments. Due to the different absorption characteristics of nucleic acids and proteins, UVC irradiation mainly affects the nucleic acid of pathogens and leukocytes while proteins are largely preserved. UVC treatment significantly reduces the infectivity of platelet units contaminated by disease-causing viruses and bacteria. In addition, it inactivates residual white blood cells in the blood components while preserving platelet function and coagulation factors. Since no photoactive compound needs to be added to the blood units, photoreagent-related adverse events are excluded. Because of its simple and rapid procedure without the need to change the established blood component preparation procedures, UVC-based pathogen inactivation could easily be implemented in existing blood banking procedures.
Division of Hematology/Transfusion Medicine, Paul-Ehrlich-Institut, Langen, Germany.
The past two decades saw tremendous achievements in blood safety, which are due to the commitment of blood establishments and industry, progress in technology such as the improvement of serological and NAT screening tests, and stringent regulatory control. Milestones in the legislation were the inclusion of plasma derivatives in the pharmaceutical legislation of the European Community (EC) in the year 1989 and special laws for the blood sector in EC and in member states, such as the Transfusionsgesetz (Transfusion Law) in Germany. The legal frame has to be supplemented by scientific and technical guidance, which is provided on the European level by the European Directorate for the Quality of Medicines and Health Care and by the European Medicines Agency. In the member states, guidelines taking into account the national peculiarities can be elaborated, such as the German hemotherapy guidelines issued by the German Medical Association (Bundesärztekammer) in agreement with the Paul-Ehrlich-Institut. The regulatory control of screening tests, and the introduction of NAT testing lead to a remarkably high degree of safety concerning the most relevant viruses HIV, HBV and HCV. Issues needing further attention are bacterial contamination and transfusion-associated acute lung injury (TRALI). Measures aiming at minimizing risks have to be balanced against their impact on supply. In order to ensure the assured supply with safe blood products, sustained efforts and research are needed as well as a continuous dialogue among blood services, industry, physicians, patients and regulatory authorities.
Evaluation of the BacT/ALERT 3D system for the implementation of in-house quality control sterility testing at Canadian Blood Services.
Canadian Blood Services, Ottawa, Ontario, Canada.
BACKGROUND: Until recently, Canadian Blood Services (CBS) was performing quality control sterility testing of blood components using three different processes. This study was conducted in order to standardize sterility testing at all CBS centers in a cost-effective manner using the BacT/ALERT 3D system. METHODS: Blood components including fresh frozen plasma, platelet concentrates, and red blood cells were inoculated with eight bacterial species at target concentrations of 1 and 10 CFU/mL. Pre- and post-spiked samples were inoculated into BacT/ALERT aerobic and anaerobic culture bottles and incubated for a maximum of 10 days. Specificity of the positive culture bottles was verified by Gram staining. Positive results obtained pre- and post-implementation of the in-house sterility testing program at CBS were collected and analyzed. Results: The BacT/ALERT3D system detected all bacteria in all blood components tested in this validation. Positive cultures were obtained within 28 h of incubation with the exception of Propionibacterium acnes which was detected within 134 h. The percentage of positive cultures ranged from 0.01% to 0.2%. All contaminants isolated were either normal skin flora or environmental microorganisms. Conclusions: This study demonstrates the capability of the BacT/ALERT3D system to detect aerobic and anaerobic bacterial contamination in all tested blood components, thereby supporting its use for quality control sterility testing and not only bacterial screening. A standardized process will allow CBS to evaluate and compare blood collection and manufacturing practices across the country.
Monitoring bacterial contamination in equine platelet concentrates obtained by the tube method in a clean laboratory environment under three different technical conditions.
Grupo de Investigación Terapia Regenerativa, Departamento de Salud Animal, Universidad de Caldas, Calle 65 No 26-10, Manizales, Caldas, Colombia.
Summary Reasons for performing study: There is a growing interest in the use of autologous platelet concentrates (PCs) as treatment for chronic musculoskeletal diseases in horses. However, there is no information on the risk of bacterial contamination during their preparation. Objectives: To: 1) assess the risk of bacterial contamination in equine PCs obtained by the tube method under 3 technical conditions: a) in a laminar flow cabinet, in a clean laboratory environment both with (b) and without (c) Bunsen burner; 2) identify the critical points of the process of PCs preparation with risk of bacterial contamination; and 3) identify the potential bacterial contaminants in the process and their antibiotic susceptibility. Methods: Bacteriological samples were taken from: the skin (shaved or unshaved) of the venipuncture site in 15 horses, both before and after being disinfected; hands and throat of the operator; caps of the tubes where the blood was processed; environment where the equine blood samples were collected; laboratory environment; laminar flow cabinet; bacteriological stove; and PCs obtained under 3 technical conditions. Results: Bacteria were isolated from nonaseptically prepared equine skin, hands and throat of the operator, and the place where the blood samples were taken. Bacteria were not isolated from tube caps, laboratory environment, laminar flow cabinet or PCs. The isolated bacteria were normal biota from equine skin, human skin and throat, and environmental contaminants. Of the isolated bacteria, 23% were resistant to penicillin, 19% to ampicillin, 2.12% to ceftiofur, 3.2% to sulphamethoxazole/trimethoprim and 1.1% to enrofloxacin. Resistance to amikacin and gentamicin was not seen. Conclusions and potential relevance: Uncontaminated PCs can be obtained by the tube method in a clean laboratory environment without the need for either a laminar flow cabinet or a Bunsen burner. It is mandatory to perform the procedure following strict aseptic technique.
T Montag-Lessing, M Störmer, U Schurig, J Brachert, M Bubenzer, U Sicker, R Beshir, I Spreitzer, B Löschner, C Bache, B Becker, C K Schneider
Fachgebiet Mikrobielle Sicherheit, Paul-Ehrlich-Institut, Paul-Ehrlich-Str. 51-59, 63225, Langen. firstname.lastname@example.org
Today, sterility of parenteral drugs is practically guaranteed. Well-defined procedures in the pharmaceutical industry enable effective protection against contamination by bacteria and fungi. In contrast, problems regarding microbial safety of advanced therapy medicinal products (ATMPs), especially of cell therapeutics, are at best only partially solved. The latter should be understood as a challenge for manufacturers, regulators, and physicians. Many of the manufacturing principles mentioned above are not applicable in production of cell therapeutics. Sterility of source materials cannot be guaranteed and the hitherto known procedures for sterilization are, as a rule, not feasible. Thus, the sterility of the final product cannot be guaranteed. Considering the extremely short shelf life of many cell therapeutics, sometimes only a few hours, the results from established methods for sterility testing are often available too late. Furthermore, the sterility of a test sample does not indicate sterility of the whole product. In most cases, conventional methods for pyrogen testing are not applicable for ATMPs. This paper demonstrates relevant limitations regarding microbial safety and pyrogenicity. Possibilities to overcome these problems are discussed and some novel solutions are proposed.
Department of Microbiology, Royal Victoria Infirmary, Newcastle upon Tyne, UK. email@example.com
Platelet transfusions have the highest incidence of post-transfusion sepsis compared with any other blood products. Recent reports suggest that platelet-related bacteraemia occurs at a frequency of approximately 50 times greater than that for red blood cells. The source is usually skin contaminants from the donor and several organisms have been implicated, the commonest of which are coagulase-negative staphylococci. This report describes a case of serious Staphylococcus aureus sepsis following platelet transfusion, and discusses relevant methods to detect and prevent bacterial contamination of blood products.
Reduction of the risk of bacterial contamination of blood components through diversion of the first part of the donation of blood and blood components.
Giancarlo Maria Liumbruno, Liviana Catalano, Vanessa Piccinini, Simonetta Pupella, Giuliano Grazzini
Centro Nazionale Sangue, Istituto Superiore di Sanità, Roma;
Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
Background Routine bacterial monitoring of apheresis platelet concentrates (APC) and pooled platelet concentrates (PPC) was introduced in two German blood services using culture and real-time reverse transcriptase (RT)-polymerase chain reaction (PCR). The results of testing are reviewed and used to discuss different strategies for detection of bacterial contamination of PCs. Study Design and Methods Two thousand three hundred and sixty-two APCs and 1993 PPCs have been tested by real-time RT-PCR and the BacT/Alert automated culturing system using aerobic and anaerobic culture bottles. After standard processing of PCs and storage of 22-24 h at 20-24 degrees C with agitation, samples were taken under aseptic conditions. Reactive culture bottles were confirmed as positive and bacterial isolates were identified by 16S rRNA analysis and biochemical tests. Results Seventeen of 2362 tested APCs were reactive in culture and one also in RT-PCR. Of these, 13 APCs were identified as initially positive as Staphylococcus warneri (n = 1, positive in aerobic and anaerobic culture), Propionibacterium acnes (n = 12, positive only in anaerobic culture) and four were initially reactive. Two of 1993 PPCs were initially reactive (anaerobic) and two more were confirmed positive (anaerobic) from a repeat culture and identified as P. acnes. All remaining specimens were tested negative. Conclusion Our study demonstrates that the predominant organisms implicated in platelet bacterial contamination are part of the human skin flora. Inoculating blood culture systems and anaerobic cultivation detects these bacteria after approximately 3-7 days when blood products have been transfused. Based on the presented data different screening strategies are discussed.
Paul Ehrlich Institute, Section Microbial Safety, Langen, Germany. firstname.lastname@example.org
Since the impressive reduction of transfusion-transmitted virus infections, bacterial infections by blood transfusion represent the most important infection risk. Platelet concentrates are the current focus of attention, as they are stored under temperature conditions which allow growth of contaminating bacteria up to 10(10) and more microbes per platelet bag. This paper does not consider the pathogen reduction methods but will assess suitable screening methods. Beside conventional microbiological approaches or surrogate markers, several efficient methods able to detect bacterial contamination in platelets are available on the market. They need to be divided into two different methodological principles: the cultivation methods and rapid methods. Cultivation or incubation methods require some time for signal production as they depend on growth of microbes. Thus, they have to be combined with early sampling, i.e., the sample to be examined has to be drawn from the blood component 1 day after donation. Their advantage is the relatively uncomplicated implementation into the logistics of blood banks. Because of the initially very low count of bacteria after donation, a certain small sampling error in application of that strategy remains. Rapid methods are able to produce the diagnosis within a short time. Therefore, they allow postponing of sample drawing, ideally up to the time immediately before transfusion. However, this procedure causes logistic complications. On the other hand, late sampling combined with a rapid method will prevent the transfusion of highly contaminated platelet concentrates leading to acute septic shock up to the death of the patient. Considering the sum of different aspects including the supply of patients, the potential improvement of microbial safety of platelet concentrates is comparable in both strategies.
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Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA.
Practical methods to clean ITER's diagnostic mirrors and restore reflectivity will be critical to ITER's plasma operations. We describe a technique to assess the efficacy of mirror cleaning techniques and detect any damage to the mirror surface. The method combines microscopic imaging and reflectivity measurements in the red, green, and blue spectral regions and at selected wavelengths. The method has been applied to laser cleaning of single crystal molybdenum mirrors coated with either carbon or beryllium films 150-420 nm thick. It is suitable for hazardous materials such as beryllium as the mirrors remain sealed in a vacuum chamber.
Vox Sang. 2012 Aug ;103 (2):122-9 22348748
Audit on the usage of plasma derived/recombinant coagulation factor concentrates at a German University Hospital.
Department of Transfusion Medicine and Hemostaseology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany Medical Centre for Information and Communication Technology, University Hospital Erlangen, Erlangen, Germany.
Background There is a lack of data on the usage of plasma derived/recombinant coagulation factor concentrates (PD/RCFC) regarding diagnostic categories. An audit of PD/RCFC and blood component usage at a tertiary care teaching hospital in northern Bavaria was conducted. Study design and methods All blood components and PD/RCFC transfused at a university hospital (Erlangen, Germany) during the year 2006 were analysed. Transfused blood products were listed by major diagnostic categories (MDC) formed from principal diagnoses of recipients according to the International Classification of Diseases, tenth revision and German modification. Results Blood component usage has markedly increased since last surveyed in 1994 through 1996. The diagnostic categories responsible for most transfusions have not changed since. Antithrombin is the PD/RCFC used most, whereas most money for PD/RCFC was spent on FVIII concentrates. Polytrauma patients need most fibrinogen, whereas most of FXIII is needed in patients with malignancies. Patients with prolonged artificial ventilation receive PCC most often. Altogether, three MDCs (Pre, 17, 05) accounted for 80·5% of costs created by PD/RCFC transfusion. Conclusion This study provides for the first time combined data on blood component and PD/RCFC usage in a German university hospital. It shows that the MDCs responsible for most of the costs in transfusion therapy with blood components and with PD/RCFC are few, and are the same. At the same time, blood bank information software should be further improved in order to be able to identify new trends in hemotherapy in more detail.
Vox Sang. 2012 Jul ;103 (1):49-54 22220569
Precise pH measuring of platelet concentrates containing additive solution - the impact of the temperature.
Department of Transfusion Medicine and Haemostaseology, University Hospital of Erlangen, Erlangen, Germany.
Background and Objectives Blood gas analysers measuring pH at 37°C (pH37) are widely used for pH determination of platelet (PLT) concentrates (PCs). For reporting pH at 22°C (pH22), converting of pH37 using the correct conversion factor is mandatory. For PCs stored in PLT additive solution (PAS), such conversion factors are not yet widely available. We studied pH in samples of PCs with different PAS/plasma ratios during warming from 22 to 37°C. Materials and Methods We measured pH in 39 samples containing modified PAS-III (PAS-IIIM) with a plasma carryover of 20%, 30% or 40% or no PAS-IIIM. Differences between pH22 and pH37 (dpH) were compared within and between study groups. Correlation between pH22 and dpH was tested. Additional measurements in 33 samples with three different PLT counts were performed to study the influence of PLT count on dpH. Results pH22 and pH37 within each group and dpH or dpH/dT between study groups differed significantly. The dpH was 0·135 ± 0·040, 0·021 ± 0·009, 0·033 ± 0·011 and 0·048 ± 0·017 for samples containing 100%, 20%, 30% or 40% plasma, respectively. Correlation between dpH and pH22 was strong in 100%(r = 0·696, P < 0·001), weaker in 30% and 40%(r = 0·367, P = 0·022 and r = 0·345, P = 0·032, respectively) and not existing in 20% plasma (r = 0·153, P = 0·354). PLT count did not influence the dpH significantly. Conclusion The dpH is dependent on different PAS-IIIM/plasma ratios and pH range. For precise reporting of pH22, the respective dpH must be used if converting is necessary. Preferably, the pH should be reported at 37°C or measured directly at 22°C.
Vox Sang. 2011 Aug ;101 (2):106-11 21492183
Storage induced apoptosis of peripheral blood mononuclear cells obtained from leucoreduction system chambers.
Department of Transfusion Medicine and Haemostaseology, University Hospital Erlangen, Erlangen, Germany.
BACKGROUND AND OBJECTIVES Recently, it was reported that leucocytes obtained from leucoreduction system chambers (LRSCs) after plateletapheresis show excellent quality due to culture of dendritic cells. This study analysed apoptosis of mononuclear cells derived from LRSCs of single platelet units (SPUs) and double platelet units (DPUs) during storage. MATERIALS AND METHODS This randomized prospective study compared eighteen single and double platelet units produced with the Trima Accel cell separator. Buffy coat was drained from the LRSCs and analysed after 1, 6, 24, 48 and 72 h. CD45+ lymphocytes and CD14+ monocytes cells as well as Annexin-V+ and 7-AAD+ mononuclear cells were measured by flow cytometry. RESULTS The WBC concentration of LRSCs obtained from SPUs and DPUs differed significantly (SPUs: 0·93 ± 0·32 ×10(5) per μl WBCs; DPUs: 1·71 ± 0·55 ×10(5) per μl WBCs; P<0·001). Processed blood volume (PBV) correlated significantly with WBC concentration (r(2)=0·75, P<0·001). Fifty percent of monocytes were Annexin-V-positive 1 h after production decreasing to 30% during 24 h of storage. Compared to that, the part of late apoptotic or necrotic PBMCs increased later on, after 24 h. After 24 h, Annexin-V- and 7-AAD-positive, late apoptotic and necrotic lymphocytes and monocytes doubled. CONCLUSION PBMCs stored in autologous plasma in PVC-bags at room temperature did not show an increase of 7-AAD-positive PBMCs during 24 h prior to cell processing but increased significantly thereafter.
Department of Transfusion Medicine and Haemostaseology, University Hospital Erlangen-Nuremberg, Erlangen, Bavaria, Germany. email@example.com
The novel allele HLA-B*07:68:02 identified in two related individuals of Caucasian origin is described.
Leukemia. 2011 Apr ;25 (4):648-54 21242993
Human but not murine multipotent mesenchymal stromal cells exhibit broad-spectrum antimicrobial effector function mediated by indoleamine 2,3-dioxygenase.
R Meisel, S Brockers, K Heseler, O Degistirici, H Bülle, C Woite, S Stuhlsatz, W Schwippert, M Jäger, R Sorg, R Henschler, J Seissler, D Dilloo, W Däubener
Clinic of Pediatric Oncology, Hematology and Clinical Immunology, Center for Child and Adolescent Health, Heinrich-Heine-University, Medical Faculty, Düsseldorf, Germany. firstname.lastname@example.org
Human multipotent mesenchymal stromal cells (MSCs) exhibit multilineage differentiation potential, support hematopoiesis, and inhibit proliferation and effector function of various immune cells. On the basis of these properties, MSC are currently under clinical investigation in a range of therapeutic applications including tissue repair and immune-mediated disorders such as graft-versus-host-disease refractory to pharmacological immunosuppression. Although initial clinical results appear promising, there are significant concerns that application of MSC might inadvertently suppress antimicrobial immunity with an increased risk of infection. We demonstrate here that on stimulation with inflammatory cytokines human MSC exhibit broad-spectrum antimicrobial effector function directed against a range of clinically relevant bacteria, protozoal parasites and viruses. Moreover, we identify the tryptophan catabolizing enzyme indoleamine 2,3-dioxygenase (IDO) as the underlying molecular mechanism. We furthermore delineate significant differences between human and murine MSC in that murine MSC fail to express IDO and inhibit bacterial growth. Conversely, only murine but not human MSC express inducible nitric oxide synthase on cytokine stimulation thus challenging the validity of murine in vivo models for the preclinical evaluation of human MSC. Collectively, our data identify human MSC as a cellular immunosuppressant that concurrently exhibits potent antimicrobial effector function thus encouraging their further evaluation in clinical trials.
D V Devine, G D Sher, H W Reesink, S Panzer, P A S Hetzel, J K Wong, M Horvath, G C Leitner, H Schennach, W Nussbaumer, K Genoe, J M Cioffi, F N Givisiez, M Rogerson, D Howe, G Delage, C Sarappa, Charbonneau, Y Fu, D Sarlija, T Vuk, M Strauss Patko, M Balija, I Jukić, A Ali, M-K Auvinen, E Jaakonsalo, J-P Cazenave, C Waller, D Kientz, B David, G Walther-Wenke, M Heiden, C K Lin, W C Tsoi, C K Lee, K Barotine-Toth, R B Sawant, W Murphy, B Quirke, P Bowler, E Shinar, V Yahalom, G Aprili, P Piccoli, G Gandini, K Tadokaro, V S Nadarajan, W de Kort, N Jansen, P Flanagan, P-O Forsberg, T Hervig, M Letowska, E Lachert, K Dudziak, J Antoniewicz-Papis, G de Olim, F Nascimento, S Hindawi, D Teo, R Reddy, J Scholtz, R Swanevelder, L P Rovira, S Sauleda, M A V Carasa, M P Vaquero, M A Ania, H Gulliksson, S Holdsworth, S Cotton, C Howell, C Baldwin, R M Cusick, G A Geele, C Paden, P McEvoy, J L Gottschall, L S McLaughlin, R J Benjamin, A Eder, N L Draper, J P AuBuchon, G León de González
A critical aspect of blood transfusion is the timely provision of high quality blood products. This task remains a significant challenge for many blood services and blood systems reflecting the difficulty of balancing the recruitment of sufficient donors, the optimal utilization of the donor's gift, the increasing safety related restrictions on blood donation, a growing menu of specialized blood products and an ever-growing imperative to increase the efficiency of blood product provision from a cost perspective. As our industry now faces questions about our standard practices including whether or not the age of blood has a negative impact on recipients, it is timely to take a look at our collective inventory management practices. This International Forum represents an effort to get a snap shot of inventory management practices around the world, and to understand the range of different products provided for patients. In addition to sharing current inventory management practices, this Forum is intended to foster an exchange of ideas around where we see our field moving with respect to various issues including specialty products, new technologies, and reducing recipient risk from blood transfusion products.
Haemoglobin Oxygenation of Retinal Vessels in Branch Retinal Artery Occlusions over Time and Correlation with Clinical Outcome.
Klinik für Augenheilkunde, Universitätsklinikum Jena.
OBJECTIVE: Purpose of these study was the evaluation of a new method for the measurement of haemoglobin oxygenation in retinal vessels. Patients with branch retinal artery occlusion have been measured before and after a rheological therapy. METHODS: The haemoglobin oxygenation in retinal vessels was measured by the "oxygen module"(Imedos GmbH, Jena, Germany) which uses a special filter (transmission at 548 and 610 nm, band width 10 nm) in the illumination path of a fundus camera. Fundus images were acquired by a colour CCD camera and specific software was used for vessel tracking and calculation of their haemoglobin oxygen saturation. 11 patients with branch retinal artery occlusions, average age 63.4 +/- 11.7 years were investigated at time of diagnosis and at the 5th day of a rheological and intraocular pressure reduction therapy. RESULTS: 10 out of 11 patients have shown an increase of haemoglobin oxygenation over time (on average from 73 +/- 16 % to 87 +/- 11 %). This increase was statistically significant (p < 0.05, Wilcoxon test). Non-affected retinal areas have also shown an increase of haemoglobin oxygenation. The visual acuity improved by one line. This increase in visual acuity was, however, not statistically significant. CONCLUSIONS: We observed an increase of the arterial haemoglobin oxygenation. One possible reason of the improvement of the haemoglobin oxygenation by the therapy may be an increase of the rheological properties of the blood. All patients showed an increase or at least a stabilisation of their visual acuity. Retinal vessel oximetry might be used as an additional parameter in the follow-up of retinal artery occlusion.
Klinik fA(1/4)r AnA currencysthesiologie und Operative Intensivmedizin, Medizinische FakultA currencyt Mannheim der UniversitA currencyt Heidelberg.
Formerly developed resuscitation fluids solely imitated the main function of the blood -oxygen transport. A research driven by the army requested an oxygen carrier that does not need cross typing and cooled storage . Artificial oxygen carriers (AOC) use either the molecular oxygen bondage to hemoglobin: HBOC-"hemoglobin based oxygen carriers" or the physical dissolution of oxygen in the blood plasma compartment by hyperbaric pressure in perfluorocarbon emulsions (PFC). Decades of preclinical and clinical research did pass but the results were disappointing- in Russia, a not well designed PFC is available locally and the only approved HBOC in South Africa is not being used much. Other products, just prior to filing for FDA approval, did not achieve convincing study results and research and production was stopped. Some trials have been stopped by the FDA for safety reasons, half of trials with the primary endpoint reduction of allogeneic transfusion requirement were unsuccessful or offset by an increased blood requirement later. However, some ventures currently are trying to use the knowledge gained so far and are investigating third and fourth generation products of artificial blood components. These imitate the cellular structure of red cells as micells, nanocapsules,(ABC- artifical blood cells) or gas bubbles (microbubbles), admixture of volume substitutes such as starches, gelatin or albumin or use hyperbaric oxygenation . Artificial platelets are in clinical phase IIa, recombinant albumin in phase III. In this article, a short overview about the current situation on artifical blood products is given. The critical point for the break through for artificial blood products did not come yet but could be ahead-
Climacteric. 2010 Apr ;13 (2):187-91 19657787
Department of Transfusion Medicine and Hemostaseology, University Hospital Erlangen, Erlangen, Germany.
Black cohosh is one of the most popular herbal therapies for premenstrual discomfort, hot flushes and other climacteric and menopausal symptoms. Most often, it is tolerated well. However, there are some recent reports on serious adverse events, probably associated with this complementary and alternative herbal medicine. We report a case of coagulation activation, fluid retention and transient autoimmune hepatitis most likely triggered by the use of black cohosh. Diagnostic procedures aimed to explain lower leg edema are not uncommon in the age group of women suffering from climacteric and menopausal symptoms. Therefore, black cohosh-induced fluid retention and coagulation activation should be considered in differential diagnosis, especially if thrombosis has been excluded.
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Vox Sang. 2012 Nov 8;: 23134556
Edinburgh University, Edinburgh, UK.
Background and Objectives Pathogen inactivation (PI)-treated plasma and platelets are increasingly becoming the products of choice, where licensed. This review summarizes the clinical evidence available for licensed component PI technologies and red cell PI under development. Materials and Methods Available literature on licensed technologies was reviewed. Results For the plasma and platelets technologies available, evidence for the inactivation of most pathogens is good, except for certain nonenveloped viruses. Clinical trials and haemovigilance programmes suggest the observed loss of potency is of little clinical significance, with some technology-specific exceptions. Concerns over adverse toxicological effects or neoantigen formation have not been confirmed for currently licensed products. Conclusion While platelet PI has been adopted to reduce bacterial contamination, the ability of PI methods to replace testing for emerging bloodborne infections, or as a substitute for selective pathogen testing, gamma-irradiation or even leucodepletion, make adoption of PI for components increasingly attractive.
Transfus Med. 2012 Oct 1;: 23020303
Bacterial contamination of blood products at the Croatian Institute of Transfusion Medicine: results of eleven-year monitoring.
Croatian Institute of Transfusion Medicine, Zagreb, Croatia.
OBJECTIVES: The aim of this study is to present the results and experiences of the Croatian Institute of Transfusion Medicine (CITM) in blood product testing for the presence of bacterial contamination. This is the first study analysing the results of bacterial testing of blood products in Croatia. METHODS: Results of monitoring blood products for the presence of bacterial contamination during an 11-year period (2000-2010) were retrospectively analysed. As universal screening of platelet concentrates for bacterial contamination is not mandatory in Croatia, the results presented refer to the products tested within the frame of statistical process control. RESULTS: A total of 23 130 blood products were tested during the study period. There were 122 (0·53%) initially positive and 41 (0·18%) confirmed positive blood products, whereas suspicion of bacterial contamination could be neither confirmed nor ruled out in 8 (0·03%) blood products. While the frequency of bacterial contamination of plasma products was very low (0·03%), there was no statistically significant difference between bacterial contamination of platelet concentrates (0·26%) and RBC concentrates (0·20%). There were 73 (0·32%) false-positive blood products, with nearly equal proportion of causes related to laboratory contamination (n = 34; 0·15%) and those related to the testing system (n = 39; 0·17%). CONCLUSION: The results obtained in the study did not differ significantly from literature data. A number of measures to reduce the risk of bacterial contamination of blood products have been implemented at CITM. The introduction of universal screening of platelet concentrates for the presence of bacterial contamination should be taken into consideration.
Transfusion. 2012 Jun 28;: 22738255
Transfusion reactions: a comparative observational study of blood components produced before and after implementation of semiautomated production from whole blood.
From Canadian Blood Services, Ottawa, Ontario, Canada; Canadian Blood Services, Saskatoon, Saskatchewan, Canada; Canadian Blood Services, Vancouver, British Columbia, Canada; and the Cells for Life Cord Blood Institute at Toronto General Hospital, Toronto, Ontario, Canada.
BACKGROUND: A semiautomated method of component production from whole blood was implemented at Canadian Blood Services. To assess safety of the new components, the frequency of adverse transfusion events (ATEs) to platelet components (PCs) and red blood cell (RBCs) produced before and after implementation of the new method was surveyed and compared. STUDY DESIGN AND METHODS: This retrospective, observational, noninferiority study was conducted in 12 sentinel hospitals across Canada. The control group received RBCs in additive solution-3 (AS-3) and platelet-rich plasma (PRP)-produced platelets (PLTs) for 3 to 11 months before implementation of semiautomated production, and the study group received RBCs in saline-adenine-glucose-mannitol (SAGM) and buffy coat (BC)-produced PLTs for 3 to 11 months after implementation. ATE definitions at each hospital and standard practice for reporting did not change between control and study periods. Data for analysis were obtained from databases and original report forms. RESULTS: The pooled risk ratio of a reaction to SAGM versus AS-3 RBCs was 0.77 (95% confidence interval [CI], 0.66-0.90), suggesting that SAGM products had significantly lower reaction rates than AS-3 products (p < 0.01). Reported allergic reactions to RBCs decreased from 0.07%(AS-3) to 0.04%(SAGM). For PLTs, the difference in reaction rates between BC and PRP was not significant (p = 0.37), and the pooled risk ratio of BC versus PRP was 1.14 (95% CI, 0.86-1.50). CONCLUSION: The change in manufacturing method was associated with lower reaction rates to SAGM RBCs than to AS-3 RBCs. Pooled BC PLTs were noninferior to random-donor PRP PLTs with respect to ATEs.
'Sterility Testing of Blood Components and Advanced Therapy Medicinal Products'(Munich, April 29, 2010) Organized by the DGTI Section 'Safety in Hemotherapy'- Meeting Report.
Abteilung Tranfusionsmedizin und Hämostaseologie, Klinikum der Universität München, Germany.
Neither screening method completely detects all clinically relevant bacterial contaminations. The effect of sampling time and volume as well as standardization of the assay applied has also to be taken into account. Therefore, minimizing the risk of contamination during manufacture by measures such as donor selection, skin disinfection, division, and processing within closed systems remains crucial. In this context new concepts in sterility testing, especially with instable advanced therapy medicinal products (ATMPs), are needed as well as reassessment of pathogen inactivation techniques. At present hemovigilance data indicate that shortening the shelf life of platelet concentrates as introduced in Germany 2008 reduced the risk of transfusion-transmitted bacterial infections to the same extent as bacterial screening as done in Canada or the Netherlands. The evolving methodological progress, e.g. by standardizing culture methods or enhancing detection systems, requires careful follow-up in parallel to hemovigilance data in order to ensure optimal bacterial safety in hemotherapy.
Mirasol PRT system inactivation efficacy evaluated in platelet concentrates by bacteria-contamination model.
Miodrag Jocić, Miroljub Trkuljić, Dragana Jovicić, Nemanja Borovcanin, Milena Todorović, Bela Balint
Military Medical Academy, Institute of Transfusiology, Belgrade, Serbia.
BACKGROUND/AIM Bacterial contamination of blood components, primarily platelet concentrates (PCs), has been identified as one of the most frequent infectious complications in transfusion practice. PC units have a high risk for bacterial growth/multiplication due to their storage at ambient temperature (20 +/- 2 degrees C). Consequences of blood contamination could be effectively prevented or reduced by pathogen inactivation systems. The aim of this study was to determine the Mirasol pathogen reduction technology (PRT) system efficacy in PCs using an artificial bacteria-contamination model. METHODS According to the ABO blood groups, PC units (n = 216) were pooled into 54 pools (PC-Ps). PC-Ps were divided into three equal groups, with 18 units in each, designed for an artificial bacteria-contamination. Briefly, PC-Ps were contaminated by Staphylococcus epidermidis, Staphylococcus aureus or Escherichia coli in concentrations 10(2) to 10(7) colony forming units (CFU) per unit. Afterward, PC-Ps were underwent to inactivation by Mirasol PRT system, using UV (lambda = 265-370 nm) activated riboflavin (RB). All PC-Ps were assayed by BacT/Alert Microbial Detection System for CFU quantification before and after the Mirasol treatment. Samples from non-inactivated PC-P units were tested after preparation and immediately following bacterial contamination. Samples from Mirasol treated units were quantified for CFUs one hour, 3 days and 5 days after inactivation. Results. A complete inactivation of all bacteria species was obtained at CFU concentrations of 10(2) and 10(3) per PC-P unit through storage/investigation period. The most effective inactivation (10(5) CFU per PC-P unit) was obtained in Escherichia coli setting. Contrary, inactivation of all the three tested bacteria species was unworkable in concentrations of > or = 10(6) CFU per PC-P unit. CONCLUSION Efficient inactivation of investigated bacteria types with a significant CFU depletion in PC-P units was obtained--3 Log for all three tested species, and 5 Log for Escherichia coli. The safety of blood component therapy, primarily the clinical use of PCs can be improved using the Mirasol PRT system.
Biologicals. 2012 May ;40 (3):187-90 22119012
Canadian Blood Services, Research & Development, 2350 Health Sciences Mall, Vancouver, BC, Canada V6T 1Z3; University of British Columbia Centre for Blood Research, Vancouver, Canada.
There are a number of possible methods for the preparation of blood components. These vary with respect to risks and benefits to the blood system operation, to the donor and to the recipient. An understanding of these risks is necessary when deciding what component production strategies to pursue. This manuscript reviews the elements that should be considered when choosing which components to produce. The two broad schemas for component production are apheresis and the production of components from whole blood donations. The development of apheresis technologies brought significant benefits to the patient including improving the access to specialty products such as HLA-matched platelets. Benefits to blood centers include the collection of multiple transfusion doses from a single collection procedure. The challenges include the cost of the technology and a small increased risk to donors. Whole blood component preparation offers two main forms of technology: platelet rich plasma, and buffy coat, both of which are driven by platelet production. The two have different risk profiles, with overall benefits being more favorable to buffy coat production methods particularly with respect to improved process control. Issues such as donor variability affect all production methods and require further research.
Transfusion. 2012 Apr ;52 (4):810-8 22060700
Development of a quality monitoring program for platelet components: a report of the first four years' experience at Canadian Blood Services.
Elena Levin, Craig Jenkins, Brankica Culibrk, Maria I C Gyöngyössy-Issa, Katherine Serrano, Dana V Devine
From the Canadian Blood Services, UBC Centre for Blood Research, Vancouver, British Columbia, Canada; and Canadian Blood Services, Ottawa, Ontario, Canada.
BACKGROUND A quality monitoring program (QMP) for platelet concentrates (PCs) was implemented at Canadian Blood Services (CBS) to improve standards and to better understand platelet (PLT) products by supplementing routine quality control (QC). STUDY DESIGN AND METHODS Annual surveys of PCs from CBS production sites were conducted, with four completed to date (QMP Cycles 1-4) spanning two different PC production methods: PLT-rich plasma (PRP) and buffy coat (BC). Randomly selected PCs were sent to a central laboratory and tested 1 day after expiry. An expanded panel of tests including CD62P expression by flow cytometry, mean PLT volume, PLT count and morphology, extent of shape change, and PLT metabolic parameters, were applied. RESULTS QMP data on the implementation of the BC production method across CBS indicated that BC PCs have less variable in vitro quality measures than PRP PCs. For the QC parameters pH and PLT count per unit, the range of mean values from each site for QMP 3 and 4 fell well within the range defined by regulatory standards, a first step in defining quality benchmarks for PCs. Of the extended panel of quality parameters, CD62P expression was the most sensitive indicator of change and identified an issue with the implementation of the BC PC production method at one site, which was subsequently remedied. CONCLUSION A QMP was found to be useful to monitor production processes across sites and highlights best practice approaches while deepening understanding of the quality of PLT products at CBS.
Interventions Implemented to Reduce the Risk of Transmission of Bacteria by Transfusion in the English National Blood Service.
NHS Blood and Transplant, London, UK.
SUMMARY: BACKGROUND: Bacterial contamination remains a significant problem in transfusion medicine. A National Health Service Blood and Transplant (NHSBT) study and surveillance data indicated skin commensals derived from the skin of the donor are the major contaminants of blood components. NHSBT therefore explored two interventions: improved donor arm disinfection and diversion. METHODS: IMPROVED DONOR ARM DISINFECTION: Commercial and in-house methods of disinfection were evaluated. Swabs at the venepuncture site were taken before and after disinfection and the reduction in bioburden determined. Diversion: Special collection bags were manufactured to allow the initial volume of blood to flow into a pouch, representing the diversion pouch and then the next flow of blood into another pouch representing the collection bag. Pouches were screened for the presence of bacteria. The reduction in bacterial contamination was then determined. RESULTS: A two-step commercial procedure (Donor Prep Kit; DPK) consisting of 70% isopropyl alcohol followed by tincture of iodine was shown to be a best practice procedure (2-min procedure). A 99.79% reduction was obtained, and this method was 10 times more effective than current practice at that time. The DPK was shown in a field trial to increase donor waiting time. A second study was initiated to find a more rapid procedure. ChloraPrep®, consisting of 2% chlorhexidine gluconate and 70% isopropyl alcohol, was shown to have equivalent disinfection efficiency as the DPK, but only took 1 min to perform. In 2006, ChloraPrep was introduced as the national method of donor arm disinfection. Diversion was shown to give a 47% reduction in contamination and was introduced nationally in 2002. CONCLUSION: Improved donor arm disinfection and diversion are effective, low-cost interventions, but do not eliminate all bacterial transmissions. In 2011, bacterial screening of platelet components was introduced by NHSBT to further increase the safety of the blood supply.
DRK-Blutspendedienst NSTOB, Institut Springe, Langen, Germany.
SUMMARY: Bacterial contamination remains a leading factor for transfusion-associated serious morbidity and mortality. Pathogen reduction procedures offer a pro-active approach to prevent bacterial contamination of cellular blood components and especially of platelet concentrates. In the past, the laboratory evaluation of the effectiveness of the pathogen reduction procedures to minimise the bacterial load of blood components has been primarily based on log reduction assays similar to the assessment of antiviral activities. Bacteria strains with the ability to multiply in the blood components are seeded in highest possible cell numbers, the pathogen reduction procedure is applied, and the post-treatment number of bacteria is measured. The effectiveness of the procedure is characterised by calculating the log reduction of the post- to pre-treatment bacteria titres. More recently, protocols have been developed for experiments starting with a low bacteria load and monitoring the sterility of the blood component during the entire storage period of the blood component. Results for 3 different pathogen reduction technologies in these experimental models are compared and critical determinants for the results are addressed. The heterogeneity of results observed for different strains suggests that the introduction of international transfusion-relevant bacterial reference strains may facilitate the validity of findings in pathogen reduction experiments.
Gabriele Walther-Wenke, Walter Däubener, Margarethe Heiden, Jochen Hoch, Britt Hornei, Peter Volkers, Carl Heinz Wirsing von König
Zentrum für Transfusionsmedizin Münster, DRK-Blutspendedienst West, Münster.
SUMMARY: Requirements for bacterial testing of blood components on a defined quantity as part of routine quality control were introduced in Germany by the National Advisory Committee Blood of the German Federal Ministry of Health in 1997. The philosophy was to establish standardized methods for bacterial testing. Numerous measures to reduce the risk of bacterial contamination were implemented into the blood donation and manufacturing processes between 1999 and 2002. German Blood establishments performed culture-based bacterial testing on random samples of platelet concentrates (PCs), red blood cells (RBCs) and fresh frozen plasma (FFP) and reported data out of the production periods 1998, 2001 and 2005/2006. While the bacterial contamination rate of apheresis PCs remained nearly unchanged, it decreased by 70% for pooled PCs to a rate of 0.158% in the last observation period. Leukocyte-depleted RBCs with diversion of the initial blood volume showed a contamination rate of 0.029% which is significantly lower than that of RBCs without leukocyte depletion and diversion (0.157%). The contamination rate of plasma decreased by 80%. Preventive measures resulted in a significant reduction of bacterial contamination of blood components. Long-term monitoring with standardized methods for bacteria testing supports evaluation of the cumulative effect of contamination reducing measures.