Comparative Analysis of AB vs. ABO-specific Plasma for Desensitization in Blood Group O Recipients: An In Vitro Study.

Neutralizing capacity measurement (NCM) of soluble ABH substances (SAS) in plasma was assessed to guide the selection of the appropriate ABO group of fresh-frozen plasma (FFP) for plasma exchange (PE) in blood group O recipients with ABO-incompatible transplantations. Neutralizing capacity was assessed by measuring anti-A and/or anti-B titers in samples comprising one unit of O FFP and 10 O EDTA plasma samples and subtracting the binary logarithm of the titer in each group with a saline dilution. Ten EDTA plasma samples with Lewis b (Leb) antigen positivity and 10 sets of pooled FFP from each blood group were used as diluents. In O FFP, the NCM values (mean±SD) were 3.4±0.52 (2.6±0.52) and 2.6±0.52 (1.5±0.3) in B and AB for IgM (total antibody) anti-B (both P<0.001), and in the 10 O EDTA plasma samples, they were 3.9±0.88 (3.1±0.88) and 3.2±0.79 (2.4±0.97) for IgM (P=0.0013) and total anti-B (P=0.025), respectively. In vitro analysis revealed that B FFP is more effective than AB FFP in reducing IgM and total anti-B antibody titers in O recipients, regardless of Leb antigen positivity.

Optimizing the Hospital Blood Bank Stock in Korea: A Comparative Analysis of the Uniform 5-Day Stock Index and a Novel Blood Stock Index.

Background: Maintaining optimal blood inventory levels in hospitals is important to prevent blood shortage and wastage. We aimed to provide an efficient blood inventory management strategy for hospital blood banks nation-wide by comparing the current use of 5-day issuable stock (IS) with Lim's IS as a novel target IS. Methods: The average and CV of daily usage (DU) were calculated from information entered into Korea's Blood Management System by 194 participating hospitals in 2019 and 2020. Using these data, Lim's IS was calculated by determining the simulated annual average blood shortage day nearest to 1 for each blood group in each hospital. The 5-day IS (5IS) was estimated by multiplying the average DU in 2018 by five to count the shortage days in 2019. Results: The average DU (0.3-231.3 units) and corresponding CV (0.33-7.14) in the participating hospitals were inversely proportional (r=-0.699 to -0.695). The hypothetical averages of 5IS and Lim's IS were 27.0±41.2 and 24.7±20.8, respectively (P=0.006). The shortage days for 5IS and Lim's IS were 8.9±22.7 and 1.0±1.9, respectively (P<0.001). Conclusions: While 5IS was unacceptable for universal application, Lim's IS remained near one shortage day and is considered more efficient than 5IS. Hospitals should implement indicators that consider DU and its variations. This is the first study to introduce Lim's IS as an indicator of optimal blood inventory, and the data are expected to provide guidance for effective blood inventory management nationwide, particularly during blood shortages.

Investigation of Discrepant ABO Blood Grouping Results from an Autoanalyzer.

Background: A paucity of studies evaluating failed cases of ABO grouping using autoanalyzers exists. We investigated autoanalyzer rejected cases, including serologically suspicious ABO subgroups and discrepant ABO blood grouping results from Erytra Eflexis (Grifols, Spain), to demonstrate efficient use of autoanalyzers for ABO grouping. Methods: Samples requested for ABO grouping throughout 2020 were tested using two Eflexis instruments and standard ABO RhD and reverse grouping cards. Neonatal cards were not used. When necessary, a conventional tube technique (TUBE) was used to resolve rejected/discrepant Eflexis ABO grouping results. Results: The overall sample rejection rate (RR) was 3.2% (628/19,466), 1.3% of which were due to various error flags and 1.9% for discrepant results. Cases from neonates ≤1 year old accounted for 35.3% of the rejected cases based on Eflexis results. The ABO groups with the highest and lowest RR (excluding neonates) were A and O, respectively. The 628 samples resulted in 682 rejections, which were frequently associated with reverse grouping, including 28.4% against A1 and 54.5% for B red cells. Among 14 serologically weakened A and/or B blood groups, six A2BW and two ABw, which had been missed by Eflexis, were detected using TUBE and our follow-up laboratory criteria. Conclusions: The ABO group and a proportion of neonatal samples influenced the RR due to weak reverse grouping reactivity, especially toward B red cells. Confirmatory ABO grouping by TUBE in a new patient and/or extra rejection criteria for forward grouping are needed to detect cis-AB, which is relatively common in Korea.

External quality assessment providers' services appear to more impact the immunohaematology performance of laboratories than national regulatory and economic conditions.

OBJECTIVES: Medical laboratories may, at their own discretion, exceed but not undercut regulatory quality requirements. Available economic resources, however, may drive or hinder eagerness to exceed minimum requirements. Depending on the respective scopes of regulatory and economic framework conditions, differing levels of quality efforts to safeguard laboratory performance can be anticipated. However, this has not yet been investigated. METHODS: Immunohaematology external quality assessment (EQA) results collected by 26 EQA providers from their participant laboratories in 73 countries from 2004 to 2019 were evaluated. Error rates were aggregated in groups according to the respective national regulatory and economic framework conditions, to whether or not expert advice was provided in case of incorrect results, and the frequency of EQA samples. RESULTS: These representative data indicate no association between national regulatory (mandatory participation in EQA, monitoring of performance of individual laboratories by authorities, financial consequences of incorrect results) and economic (level of national income, share of national health expenditure) conditions to the quality performance of medical laboratories in immunohaematology. However, EQA providers' support for laboratories in the event of incorrect results appear to be associated with lower error rates, but a high EQA sample frequency with higher error rates. CONCLUSIONS: Further research into the impact of introducing or changing services of EQA providers is needed to confirm the results found in this first of its kind study.

Early recognition of possible transfusion reactions using an electronic automatic notification system for changes in vital signs in patients undergoing blood transfusions.

BACKGROUND: The study was designed to evaluate the ability of a novel electronic automatic notification system (EANS) to detect significant changes in transfusion-associated vital signs (VSs) during transfusion and to determine whether the EANS improved acute transfusion reaction (ATR) detection rates and suspected ATR reporting rates. STUDY DESIGN AND METHODS: VSs were measured three times per unit or batch product transfused:-before, 15 minutes after commencement, and at the completion of the transfusion-and recorded on the EANS. Significant changes in VSs were defined as increased temperature (≥38°C or ≥1°C change in baseline temperature), 20 mm Hg or 20% increase or decrease in systolic blood pressure, or 20% increase in pulse rate. The 6-month periods preceding and after the introduction of the EANS were defined as "before" and "after." Data from these periods were used for comparison and evaluation. RESULTS: During the after period, 945 notifications were reported from the EANS and 521 suspected ATR were detected. The suspected ATR reporting rates for the before and after were 0.29% (73/25 213) and 2.06% (521/25 304, P < .001) and the ATR detection rates before and after were 0.13% (33/25 213) and 0.49% (116/25 304, P < .001), respectively. Among 116 ATR cases, 49.1% could be detected only by significant changes in VSs. CONCLUSION: The EANS was very effective in detecting ATRs that could have been overlooked by medical staff. Further data are needed to demonstrate the extent to which the introduction of an EANS may improve the safety of transfused patients.

Evaluation of kodecytes using function-spacer-lipid constructs as a survey material for external proficiency testing for ABO subgrouping.

BACKGROUND: It is not easy to find natural red blood cells (RBCs) with weak A (Aw ) or weak B phenotype (Bw ) for use as quality controls in ABO subgroup testing (subgrouping). The aim of this study was to prepare RBC kodecytes with synthetic blood group A and/or B function-spacer-lipid (FSL) constructs and to evaluate the possibility of using such kodecytes as a survey material for an external proficiency test (PT) to improve the quality of subgroup analysis. METHODS: Three types of survey samples, including O phenotype RBCs and A kodecytes with Aw (0.02 mg/mL FSL-A solution) and B kodecytes with Bw (0.15 mg/mL FSL-B solution) were sent to 53 laboratories for an educational trial of PT for subgrouping. Cell typing was done using the manual tube technique. RESULTS: Forty-three laboratories responded, and the re-activities of the survey samples varied from 0 to 4+ against anti-A and anti-B monoclonal reagents(MoAbs). Twenty-nine laboratories (67%) correctly grouped the Bw kodecytes as Bw . Fifteen (35%), 21 (48%), and 6 (13%) laboratories grouped the Aw kodecytes as Aw , A2 , and O phenotypes, respectively. The anti-A MoAb clone affects the results of cell typing for Aw kodecytes. The stability of kodecytes was similar to that of natural O RBCs during storage. CONCLUSION: Our kodecytes were useful as a survey material, and the survey results showed the necessity of materials for PT for subgrouping to improve the quality of laboratory analysis regardless of the different reactions according to the MoAb.

Standardization of ABO antibody titer measurement at laboratories in Korea.

BACKGROUND: Measurement of the ABO antibody (Ab) titer is important in ABO-incompatible transplantation. However, to the best of our knowledge, no standard protocol or external survey program to measure the ABO Ab titer has been established in Korea. We investigated the current status of ABO Ab titer measurements at various laboratories in Korea and the impact of the protocol provided to reduce interlaboratory variations in the methods and results of ABO Ab titers. METHODS: The Korean external quality assessment of blood bank laboratories sent external survey samples with a questionnaire to 68 laboratories across Korea for the measurement of ABO Ab titers in May 2012. After 6 months, a second set of survey samples were sent with a standard protocol to 53 of the previously surveyed laboratories. The protocol recommended incubation at room temperature only and use of the indirect antihuman globulin method for the tube test as well as and the column agglutination test (CAT). RESULTS: Several interlaboratory variations were observed in the results, technical procedures, and methods selected for measurement. We found that 80.4% laboratories hoped to change their protocol to the provisional one. Additionally, CAT showed significantly lower variation among laboratories (P=0.006) than the tube test. CONCLUSIONS: Our study provides baseline data regarding the current status of ABO Ab titer measurement in Korea. The standard protocol and external survey were helpful to standardize the technical procedures and select methods for ABO Ab titer measurement.

Comparison of ABO antibody titers on the basis of the antibody detection method used.

BACKGROUND: Detection methods for ABO antibody (Ab) titers vary across laboratories, and the results are different depending on the method used. We aimed to compare titer values using different detection methods for the measurement of ABO Ab titers. METHODS: For ABO Ab detection, pooled group A or B red blood cells (RBCs) were reacted with each of 20 sera from blood groups A, B, or O without dithiothreitol treatment. The room-temperature (RT) incubation technique and the indirect antiglobulin test (IAT) were used in the tube test and gel card test. Flow cytometry (FCM) was performed by using anti-IgM and anti-IgG Abs. RESULTS: Regardless of the blood groups tested, the FCM assay with anti-IgM showed the highest titer compared to the tube test and gel card test with RT incubation in both. The tube test with IAT showed a higher titer than the gel card test with IAT (Gel-IAT) or FCM with anti-IgG in blood group A and B, while Gel-IAT showed the highest titer relative to the other tests, only for the anti-A Ab in blood group O. CONCLUSIONS: There were significant differences in the titers depending on the detection method used, and each method showed a different detection capacity for each ABO Ab depending on the ABO blood group tested. Therefore, caution should be exercised in interpreting ABO Ab titer results, taking into consideration the detection method used and the blood group.

Effects of platelet lysate preparations on the proliferation of HaCaT cells.

BACKGROUND: Standard protocols are lacking for the preparation of platelet lysates (PL) as an alternative to using fetal bovine serum as a cell culture supplement. This study aimed to establish optimum conditions for preparing PL for use in cell cultures. METHODS: Cell density in three pooled platelet concentrates (PC) were adjusted to 1×10(12)/L and 2×10(12)/L. PL was prepared from PC by 1 to 3 freeze-thaw (FT) cycles. HaCaT cells were cultured in media supplemented with 5% or 10% PL. Cell numbers were estimated using a Cell Counting Kit-8 (CCK-8; Dojindo Laboratories, Japan). Growth factors were quantified by using the Luminex 200 system (Luminex Corporation, USA). RESULTS: Cell proliferation rates in the presence of PLs were similar when prepared from PCs of both cell densities. The rates were higher in media containing 5% PL than 10% PL when prepared by two FT cycles. Concentrations of vascular endothelial growth factor (VEGF), platelet-derived growth factor-AB/BB (PDGF-AB/BB), PDGF-AA, and epidermal growth factor (EGF) were significantly higher in PL prepared from PC with a cell density of 2×10(12)/L than 1×10(12)/L PC. However, only VEGF and PDGF-AA concentrations in PLs were correlated with HaCaT cell counts. CONCLUSIONS: The 5% PL from PC with a cell density of 1×10(12)/L prepared by two FT cycles treatment was the most effective condition that supported steady HaCaT cell proliferation. Our finding may be useful for preparing PL-supplemented cell culture media.

Hemophagocytosis by leukemic blasts in B lymphoblastic leukemia with t(12;21)(p13;q22); TEL-AML1 (ETV6-RUNX1): a case report.

Blasts showing hemophagocytosis have been very rarely reported in acute lymphoblastic leukemia. We report a pediatric case of B lymphoblastic leukemia (BLL) with t(12;21)(p13;q22); TEL-AML1 (ETV6-RUNX1) showing erythrophagocytosis and thrombophagocytosis by leukemic blasts. About 4% of the leukemic blasts in marrow aspirate smears showed phagocytosis of erythrocytes, platelets, or nuclear remnants in a 3-year-old Korean boy with a diagnosis of BLL. Conventional cytogenetics and molecular analysis revealed the presence of t(12;21)(p13;q22); TEL-AML1 (ETV6-RUNX1). The patient responded well to chemotherapy and is in a state of complete remission.

Ticlopidine with Ginkgo Biloba extract: a feasible combination for patients with acute cerebral ischemia.

BACKGROUND: Even though clopidogrel is the most used drug for cardiovascular prevention, resistance occurs in significant numbers. Therefore, we evaluated platelet aggregation ability of thienopyridines in relation with various genotypes. METHOD: The study population was randomly assigned with clopidogrel (n=43), ticlopidine (n=41), or ticlopidine plus Gingko Biloba extract (EGb) (n=43). Dosage was maintained as 75mg clopidogrel daily, 250mg ticlopidine twice daily, and 250mg ticlopidine plus 80mg Gingko Biloba extract twice daily. Using multiple electrodes aggregometry, platelet aggregation was measured by activators of adenosine diphosphate (ADP), arachidonic acid (ASP), and thrombin (TRAP) at baseline (T0), 7days (T1), and 90days (T2). Side-effects were analyzed in the 3 groups. Inhibition of platelet aggregation (IPA) was defined as percent decrease at T0 and T1. Non-responsiveness (

The Effects of Helicobacter pylori on the prognosis of patients with curatively resected gastric cancers in a population with high infection rate.

PURPOSE: The goal of this study was to assess the correlation between the Helicobacter pylori status of patients who underwent curative resection for gastric adenocarcinoma and their prognosis in Eastern societies where H. pylori infection is prevalent. METHODS: Between 2006 and 2007, 192 patients who had a curative resection for the treatment of gastric adenocarcinoma were enrolled in the study. Of these patients, 18 were excluded due to an inexact evaluation of the H. pylori status, thereby leaving 174 patients in the final analysis. Serologic testing for H. pylori was assessed using an enzyme-linked immunosorbent assay kit for immunoglobulin G, and the histological presence of H. pylori was identified using the Giemsa stain. RESULTS: Of the 174 patients, 111 patients (63.8%) were confirmed for H. pylori infection. H. pylori status did not correlate with the overall or disease-free survival. For patients with stage III or IV gastric cancer, a positive H. pylori status was a significant predictive factor for recurrence over that of a negative H. pylori status (P = 0.019). Negative H. pylori status was a predictive factor for recurrence in multivariable analysis (relative risk, 2.724; 95 confidence interval, 1.192 to 6.228). CONCLUSION: Helicobacter pylori status did not correlate with the clinicopathologic factors of gastric adenocarcinoma. However, a negative Helicobacter pylori status may be a predictive factor for recurrence in patients diagnosed with advanced gastric adenocarcinoma.

Usefulness of delta value of platelet parameters on ADVIA 120 for the functional reactivity of stored platelets.

An agonist-induced expression of CD62P by flow cytometry analysis for evaluating platelet functional reactivity has some disadvantages. We investigated the usefulness of platelet parameters by ADVIA 120 to predict an agonist-induced expression of CD62P in stored platelets. The CD62P expression by flow cytometry and the platelet parameters by ADVIA 120 were studied in samples from 27 platelet pheresis products. Delta (Delta) values were calculated as the degree of change of the platelet parameters studied with or without adenosine 5'-diphosphate sodium (ADP) stimulation. The CD62P expression of the ADP-activated platelets were correlated with the Delta platelet count (r=0.517) in the short-term storage group (within 10 hr from preparation), with the platelet component distribution width (PCDW) without ADP (r=-0.744) and the DeltaPCDW (r=-0.755) in the long-term storage group (after 10 hr from preparation). Therefore, the delta values of platelet parameters on ADVIA 120 analysis in platelets between with and without ADP stimulation could be useful as a simple predictor for the functional reactivity of stored platelets.

[A hemolytic transfusion reaction due to Anti-Ku antibody in a patient with Knull phenotype: the first case in Korea].

Knull phenotype completely lacks all Kell system antigens. Anti-Ku antibody is seen in immunized persons with Knull phenotype by transfusion or pregnancy. It can cause a fatal hemolytic transfusion reaction. A 66-yr-old male patient with liver cirrhosis visited emergency center due to acute bleeding. The patient was at hypovolemic shock status: his blood pressure was 80/50 mmHg, pulse rate was 110/min and hemoglobin level was 4.4 g/dL. Because of the presence of antibody against high incidence antigen, we could not find any compatible blood for the patient. Nevertheless, 4 units of packed RBCs had to be transfused. Moderate hemolytic transfusion reaction was developed after transfusion. At endoscopic examination, blood was spurting from gastric cardiac varix. Endoscopic histoacryl injection was tried, and bleeding was successfully controlled. After bleeding stopped, he was managed for anemia using steroid and other medical therapy instead of transfusion. His hemoglobin level was improved to 7.7 g/dL at the time of discharge. Later he has been proved to have a Knull phenotype, which is very rare, and anti-Ku antibody. This report is the first case of anti-Ku in a Knull phenotype person in Korea, who experienced a moderate hemolytic transfusion reaction.

The implementation and effects of a clinical laboratory accreditation program in Korea from 1999 to 2006.

BACKGROUND: The Korean Laboratory Accreditation Program (KLAP) by the Korean Society of Laboratory Medicine (KSLM) was started in 1999. We summarized history and achievement of KLAP for the last 8 yr. METHODS: We analyzed 8 yr data (1999-2006) of historical events, trends of participating laboratories, and scores according to the impact of the question to the outcome of the tests. Inspection check lists are for 'laboratory management', 'clinical chemistry', 'diagnostic hematology', 'clinical microbiology', 'diagnostic immunology', 'transfusion medicine', 'cytogenetics', 'molecular genetics', 'histocompatibility', 'flow cytometry', and 'comprehensive laboratory test verification report'. The laboratories with score 90 or higher got 2-yr certificate and laboratories with score between 60 and 89 got 1-yr certificate. The laboratories with score below 60 failed accreditation. RESULTS: The number of accredited laboratories was 2.4 times higher in 2006 (n=227) than in 1999 (n=96). Inspection check lists have been revised 5 times till 2006. The average accreditation rate was 99.6% during these periods and the 2-yr accreditation rate was 32.4% in 2000, 45.6% in 2001, 53.3% in 2002, 47.3% in 2003, 68.5% in 2004, 37.7% in 2005, and 47.7% in 2006. Number of participants in inspector training workshops increased from 89 in 2000 to 766 in 2006. CONCLUSIONS: The KLAP has been in place successfully and stabilized over the past 8 yr. It seemed to enhance the laboratory quality. Efforts for improvement of quality control and inspector training workshops appeared to be in the main contributing factors.

[An experience of the use of Anti-HBc and Anti-HBs for blood donor screening tests at a tertiary hospital blood center in Korea].

BACKGROUND: The aim of this study was to report the first experience of using tests of antibody to hepatitis B core antigen (anti-HBc) and antibody to hepatitis B surface antigen (anti-HBs) for the selection of blood donors in a tertiary hospital blood center in Korea. METHODS: From January 2005 to December 2007, the data of all eligible donors according to the Korean Blood Regulation Law were analyzed. Anti-HBc testing was performed in all donors, but anti-HBs was tested only in anti-HBc seropositive donors. Anti-HBs negative but anti-HBc positive donors were regarded as ineligible for blood donation. Cost for donor testing was calculated based on Korean health insurance payment schedule from 2005 to 2007. RESULTS: The seroprevalence of anti-HBc in blood donors was 23.2% (162/699) and increased with increasing age. The proportion of ineligible donors for blood collection was 2.7% (19/699) of total donors and 11.6% (19/162) of anti-HBc seropositive donors. The cost of testing for anti-HBc and anti-HBs was estimated to be about 40% of the total screening cost. CONCLUSIONS: Although additional donor screening tests for anti-HBc and anti-HBs requires increased cost and relatively small number of donors are additionally excluded by these tests, they are considered to be helpful for the safety of blood products, because our blood center has characteristics with small number of donors and relatively high percentage of donors in the age group of thirties and older.

Change of platelet activation markers using flow cytometry in patients with hematology/oncology disorders after transfusion.

In spite of the frequent need of platelet transfusions, there is limited information on the association of platelet activation markers, in transfused patients with hematology/oncology disorders, with platelet function using flow cytometry. The goal of this study was to evaluate the changes of PAC-1 binding and CD62P expression, with or without agonists in patients after transfusions. Twenty-eight whole blood samples were obtained from 24 patients admitted to the department of Hematology & Oncology and transfused with platelets; these samples were compared to 30 healthy controls. Whole blood samples, either with or without agonists, such as 20 microM adenosine diphosphate (ADP) or 100 microM thrombin receptor activating peptide (TRAP), were stained with the fluorescein conjugated monoclonal antibodies PAC-1 or CD62P. Then, the percent expression for each marker was analysed using flow cytometry. ADP and TRAP induced an increased percentage of CD62P expression and PAC-1 binding after platelet transfusions compared to the samples studied before transfusion, and these findings were lower than those of the healthy controls. However, the expression of platelets without the agonists was not significantly changed, despite the transfusions. Therefore, agonist-induced platelet activation markers, studied by flow cytometry, appear to be more useful for the evaluation of platelet function after transfusions than platelet activation markers without agonists.