Seung Gyu Yun

Abstract: Anti-Sda is of no clinical significance, because it rarely causes hemolytic transfusion reactions. Even when its presence is suspected during antibody screening test, further identification of the antibody is usually not performed. We experienced a case of anti-Sda in 73 yr-old male patient showing mixed field agglutination by microcolumn agglutination. Antibody specificity could not be identified by conventional antibody identification test, and it was proven to be anti-Sda by urine neutralization test. In spite of its little clinical significance, it may give incompatible crossmatching results reacting with Sda antigen, which occurs at a high frequency in general population. When incompatible crossmatch results arising from anti-Sda are suspected, the problem may be solved by using the urine-neutralized serum of in crossmatching test.

Abstract: Background ABO antibody titration is useful for the evaluation of ABO-incompatible bone marrow or solid organ transplantations, yet the results quite vary between different test methods used. We compared the results of microcolumn agglutination and tube methods. Methods Anti-A and anti-B isoagglutionin titers were determined in 63 healthy individuals (23 O, 20 A, and 20 B blood groups) using 4 different methods: immediate spin tube (tube), microcolumn agglutination without anti-human globulin (AHG) (CAT), tube with AHG (tube-AHG) and microcolumn agglutination with AHG (CAT-AHG). Results The median (range) titers of anti-A and anti-B in group O individuals by tube, CAT, tube-AHG, and CAT-AHG methods were 64 (8-512), 64 (8-512), 128 (8-2,048), and 128 (16-2,048); 64 (16-128), 128 (16-256), 128 (16-512), and 256 (16-512), respectively. The median (range) titers of anti-A in group B and anti-B in group A individuals by the four methods were 64 (16-128), 128 (8-128), 128 (8-256), and 256 (8-256); 64 (8-128), 64 (8-128), 32 (8-128), and 64 (8-256), respectively. The isoagglutinin titer measured by CAT-AHGmethod was the highest. The titers measured by CAT and CAT-AHG methods were 0-1 titer higher than those by tube and tube-AHG methods, respectively. Whatever method was used, the isoagglutinin titers were higher in women than in men. Conclusions CAT-AHG was the most sensitive method among the four methods tested. Since AHG titer values are critical for the clinical management and CAT has less manual procedures than tube method, CAT-AHG method could be used for the standardization of ABO antibody titration in different institutions.

Abstract: Limitations due to lack of appropriate available donors for liver transplantation necessitates the use of ABOmismatched donors. Transplantation of ABO-mismatched solid organs is sometimes associated with the development of immune hemolytic anemia, which is caused by production of antibodies by the donor B lymphocytes in a primary or secondary immune response against the recipient's red blood cell antigens. This condition is referred to as Passenger Lymphocyte Syndrome (PLS). PLS is more frequent in heart and lung transplants than in liver and kidney transplants with incidence of PLS in liver transplantation at 30∼40%. When present, PLS typically manifests 1∼3 weeks after transplantation, and subsides within 3 months after symptoms are first detected. In most patients, PLS is self-limiting and exhibits mild symptoms, but in some cases PLS can be life-threatening. We report a case of immune hemolytic anemia after an ABO-mismatched liver transplantation involving a blood group O donor and a blood group A recipient, and successful treatment of the resulting PLS symptoms by transfusion of gamma-irradiated group O Red Blood Cells (RBCs) accompanied by administration of 60 mg/day of methylprednisolone for 1 week.

Abstract: Background: Unexpected antibody screening and identification tests are very important for safe blood transfusion. The micro-column agglutination test (MCAT) is widely used due to its simplicity and efficiency for detecting alloantibodies. We analyzed the frequency of unexpected antibodies at three university hospital blood banks, which use two different MCAT systems. Methods: From February 2002 to December 2009, a total of 295,876 unexpected antibody screening tests were performed at three university hospital blood banks. Two hospital blood banks (Anam and Ansan Hospitals) used the DiaMed-ID system (DiaMed Ag, Switzerland) and the other (Guro Hospital) used the Ortho BioVue system (Ortho-Clinical Diagnostics, USA) for antibody screening and identification tests. Results: The rates of detecting unexpected antibodies on screening test based on the ‘tests performed’ and the ‘persons tested’ were 1.16% per test and 0.96% per person in Korea University Guro Hospital, 0.65% and 0.41% in Korea University Anam Hospital and 0.76% and 0.57% in Korea University Ansan hospital, respectively. There were significant differences in the frequencies based on the two different systems (P＜0.001). Among the warm antibodies, Rh antibodies were more frequently detected by the DiaMed-ID system, and Lewis antibodies were most frequently detected by the Ortho BioVue System. Conclusion: We should carefully interpretate the frequency of unexpected antibodies in the Korean population because the frequencies of unexpected antibodies are different according to different employed micro-column agglutination systems.

Abstract: Since an exact ABO blood type match is essential for transfusion therapy, any ABO discrepancies should be resolved prior to the issuing of blood. The authors confirmed the ABO blood group of a 50-year-old male using genotyping. On a routine blood group test, the cell type was A+; however, anti-B was undetected in his serum. To determine the cause of this ABO discrepancy, an adsorption elution test and saliva test were performed. The presence of a weak B substance was suspected despite no evidence of the B antigen on red blood cells. Polymerase-chain-reaction restriction-fragment-length-polymorphism (PCR-RFLP) and sequencing analysis of exons 6 and 7 demonstrated that his blood type was A1Bweak (the A allele tested as the A105 subtype, while the B allele was most similar to the B302 subtype). Again, using genotyping, we subsequently confirmed the A1Bweak blood type in a leukemic patient who was in complete remission.

Abstract: BACKGROUND: Self-monitoring devices for blood glucose are widely used as a point-of-care testing (POCT) in the management of diabetic patients. In the present study, we evaluated the performance of SD CHECK GOLD Blood Glucose Testing System (SD diagnostic, Korea) using electrochemical detection technique. METHODS: SD CHECK GOLD was tested for linearity, precision and comparison of method. Other glucometers including ACCU CHEK ACTIVE (Roche Diagnostics Ltd., Germany) and ONE TOUCH ULTRA (Lifescan Inc., USA) were compared for the same categories according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. RESULTS: SD CHECK GOLD revealed good linearity in glucose concentration ranging from 50 mg/dL to 550 mg/dL (r(2)=0.9931). In the precision study, within-run precision and total-run precision (CV)s were within 10%. Excellent correlation was found between SD CHECK GOLD and Toshiba 200FR (Toshiba, Japan) (y=0.9212x, r=0.9756). CONCLUSIONS: SD CHECK GOLD showed good linearity, precision, and correlation with the reference method. No significant effect of testing procedure or operator was found. SD CHECK GOLD provided rapid and reliable results for blood glucose and seemed to be appropriate for the clinical useful in the management of diabetic patients.

Abstract: Background: In Korea, a screening panel of cells from abroad without Dia positive cells has been commonly used when a patient has an unexpected antibody screening test. It has been reported that Dia occurs with a frequency of 6.14 to 14.5% among Koreans. However, the current popular antibody screening panels contain no Dia positive cells. In this study, we evaluate the clinical usefulness of the Dia Cell Panel (Diagnostic Grifols, Barcelona, Spain) for Koreans. Methods: A total of 3,372 pretransfusion samples were employed for unexpected antibody screening testing using panels of cells by the DG Gel microtube column agglutination system, including additional Dia cells (Diagnostic Grifols, Barcelona, Spain). The positive cases in this system were confirmed again with DiaMed Dia antigen positive panel cells (DiaMed Ag, Cresssier, Morat, Switzerland) and this was followed by sequencebased Diego genotyping. Results: The positive detection rate of an unexpected antibody screening test using SeraScan Diana I and II was 1.07% (36/3372), and seven samples were reactive (1＋∼2＋) with the SeraScan Dia panel cells (0.21%). However, among the 5 available genotyped samples, two cases were typed as Di(a−b＋). Conclusion: Even though there is discrepancy between the genotype and the two antibody screening kits, the addition of Dia positive cells as unexpected antibody screening panel cells is recommended.