ADAMTS13 specifically cleaves von Willebrand factor (VWF), which is a haemostatic factor, and hydrolyzes the peptide bond between Tyr1605-Met1606 in the VWF-A2 domain. The development of a mouse monoclonal antibody recognizing the C-terminal edge residue Tyr1605, the enzymatic cleavage site of the VWF-A2 domain, enabled the direct assay of the products cleaved by ADAMTS13. An ADAMTS13 activity ELISA kit based on this principle was developed, and its fundamental performance was studied.
The minimum detection limit was 0.4% of the normal detection limit. The intra- and inter- reproducibility study showed the results of CVs as 1.1-4.7% and 2.6-7.5%, respectively. The ideal linearity extrapolated to the original point was obtained in a dilution test. No interference with the ADAMTS13 activity assay was observed at the tested concentrations in the presence of various interferants such as hemoglobin, bilirubin, chylomicron, and rheumatoid factor. EDTA completely inhibited ADAMTS13 activity.
ADAMTS13 activities of 109 plasma samples were measured using this assay kit. The samples from Upshaw-Schulman syndrome (USS), Thrombotic Thrombocytopenic Purpura (TTP), USS carrier, and normal samples showed assay values 0.5-2.7%, 0.5-58.1%, 7.7-85.3%, and 54.7-134.4%, respectively. The test kit has been proven to have a sufficient clinical discriminate ability for diagnostic testing. We observed good correlation between this method and the SDS-Agarose gel electrophoresis method (r=0.931).
This assay kit can be used for routine laboratory test in blood transfusion medicine and clinical laboratory practice.

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Background: Massive hemorrhage during surgery often results from diluted coagulopathy due to loss of coagulation factors (e.g., fibrinogen), especially in cases of thoracic aortic aneurysm, liver transplantation, and hepatoma/perihilar cholangiocarcinoma. The most important issue in preventing massive hemorrhage during surgery is transfusion therapy for hemostasis. This study analyzed the hemostatic efficacy of cryoprecipitate or fibrinogen concentrate during surgery when massive bleeding occurred.
Patients and Methods: When massive hemorrhage occurred in cases of thoracic aortic aneurysm, liver transplantation, and hepatoma/perihilar cholangiocarcinoma, we measured the fibrinogen level in plasma, and administered cryoprecipitate or fibrinogen concentrate to the patient when the fibrinogen level was below 150mg/dl(in 2007∼2008). The hemostatic efficacy of this treatment was evaluated by counting the volume of blood loss and number of transfusion units in comparison with cases of treatment with fresh frozen plasma (in 2005∼2006).
Results: We observed a rapid increase in plasma fibrinogen level and subsequent improvement in hemostasis after cryoprecipitate or fibrinogen concentrate was administered. The average blood loss decreased by 30% and the average number of transfusion units was reduced about 30% to 60% when those agents were given to patients with severe hypofibrinogenemia during surgery. The number of cases of early death due to massive hemorrhage during surgery decreased by 75% in 2007∼2008 when fibrinogen concentrate was used.
Conclusion: In patients showing hypofibrinogenemia (i.e. <150mg/dl) during surgery, administration of fibrinogen concentrate should be effective in establishing hemostatsis, and therefore in reducing blood loss and transfusion volume. This treatment should help to improve the prognosis of patients in surgery, and also to decrease the use of blood products.

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HLA genotyping is conducted using various methods. Our hospital uses PCR-Luminex (Luminex Corporation, Austin, Texas), based on reverse sequence-specific oligonucleotide (PCR-rSSO) technology. In contrast, the Japan Marrow Donor Program uses even more sensitive PCR-SBT (sequence-based typing) technology for patient registration.
Here, we describe a patient with discordant PCR-Luminex and PCR-SBT typing results. As this discrepancy was thought to arise from a mutation of HLA-B*4002, DNA sequencing of the HLA-B gene was performed. A family study was also conducted to investigate heritability. DNA sequencing results for the patient confirmed a TAC to TAT mutation in the base sequence of codon 99 in exon 3, distinguishing the new allele from HLA-B*400201. The family study confirmed that the patient's mother and younger sister also shared the new allele, suggesting heritability.
TAT, in the allele we designate as HLA-B*4002new, and TAC, in HLA-B*400201, represent synonymous substitutions in codon 99; as both are translated as tyrosine, they are serologically indistinguishable variations of HLA-B61.

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Upshaw-Schulman syndrome (USS) is a congenital thrombotic thrombocytopenic purpura (TTP) caused by a deficiency of von Willebrand factor-cleaving protease (ADAMTS13) activity due to genetic mutations. The most striking clinical picture of USS is severe neonatal jaundice soon after birth that often requires exchange blood transfusion. These patients subsequently have repeated episodes of thrombocytopenia and microangiopathic hemolytic anemia (MAHA) that are reversed by infusions of fresh-frozen plasma (FFP). Therefore, most patients with USS require FFP infusion every 2 to 3 weeks to preserve ADAMTS13 activity levels. However, FFP infusions from random donors sometimes cause side effects such as viral infections and allergic reactions. To prevent these issues, we investigated the use of divided FFP from single donor unit for a patient with USS. The patient in this report had two episodes of urticaria after FFP infusion from a random donor. After using the subdivided FFP, however, the patient did not experience urticaria in 40 FFP infusions over 22 months.

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The Japanese Ministry of Health, Labor and Welfare revised "the guidelines for the implementation of the transfusion therapy" in September, 2005. In this guideline, three requirements for computer-assisted electronic cross-matching are shown.
The first requirement is that computer systems must send a warning message in case of any discrepancy in ABO/Rh (D) typing between the donor unit and blood sample of the intended recipient. The second is that the blood type of the patient must be confirmed by two or more examinations using different specimen, and the third is that the blood type of blood products must be reconfirmed in each medical institute. The first and second requirements have already been realized by the transfusion management computer system adopted in our hospital. However, as for the third requirement, the reexamination of ABO/Rh (D) typing has been implemented, but results are not recorded in the system's blood product database.
We constructed a new transfusion management system in which ABO/Rh (D) typing of blood products can be an automated by automatic analysis machine (Auto Vue* Innova: Ortho-Clinical Diagnostics Inc.) and the result can be recorded in the blood product database. This system fulfills not only all three requirements in the guideline, but excludes human error, rationalizes the procedure, and decreases labor in operations supplying suitable blood products for the patients.
To use the computer-assisted electronic cross-matching, it is necessary that the patient's latest RBC antibody screening test is negative. At present, information on RBC antibodies of patients are not shared among medical institutions. It is desirable to share information of antibody, including the history of past antibody positivity.
The establishment of "guidelines for transfusion management systems" which include minimum functional requirements of the computer system is now expected.
*Trademark of Ortho-Clinical Diagnostics Inc.

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[Background]Medical professionals should have sufficient knowledge and training in transfusion practice. In particular, nurses play an important role in safe transfusion therapies. It is important for nurses to develop and maintain their knowledge of transfusion practice in order to ensure transfusion safety.
[Purpose and Methods]The Aomori Prefecture Joint Committee of Transfusion Practices conducted a questionnaire survey of nurses concerning their awareness and knowledge of blood transfusion. A total of 182 nurses at Aomori Prefectural Central Hospital, Kuroishi General Hospital, and Hirosaki University Hospital participated.
[Results]1. Knowledge of blood transfusion: 135 nurses (75%) had negative images or were reluctant to manage blood transfusion. 2. Knowledge of transfusion practices: 111 nurses (61%) answered correctly the initial speed of blood transfusion (1ml/min). 16% answered incorrectly about RhD-type mismatched red cell transfusion, and 69% answered incorrectly about ABO-type major mismatched red cell transfusion.
Against our expectations, this survey revealed that knowledge of transfusion practices at the three major hospitals in Aomori Prefecture was insufficient. Some nurses were managing blood transfusion despite frank uncertainty about it. The respondents also expressed their desire to learn more about transfusion practices. In conclusion, improving the level of knowledge of transfusion practices among nurses is critical to the safety of transfusion therapies.

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As a cord blood (CB) bank, we routinely reduce the volume of each CB unit by manually sedimenting red blood cells (RBCs) using hydroxyethyl starch (HES). This is a demanding technique, and an automated volume reduction of CB is expected to standardize the procedure while complying with the requirements of the quality control system. We compared the manual HES sedimentation method with the AutoXpress^TM system (AXP, Thermogenesis, New York) without HES. Preparing identical units, we assessed the total nucleated cell (TNC) count, mononuclear cell (MNC) count, CD34+cells, and colony-forming unit (CFU) content from both methods in 24 pairs. Recoveries of TNC, MNC, CD34+and total CFU for the AXP group were 88.4%, 97.3%, 93.4% and 101.2%, respectively, which were significantly better than the manual HES sedimentation group. The time required for CB processing with the AXP system was significantly shorter than that for our HES sedimentation method. The main advantage of the manual HES method was its higher RBC depletion. The recovery of cells after a freeze and thaw was comparable between the manual and AXP groups for TNC, CD34+and CFU. Use of the AXP system to enable CB banks to automate and simplify the processing procedure is feasible.

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[in Japanese]

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