Evaluation of Overnight Transfusion in Single Tertiary Hospital / 대한수혈학회지

BACKGROUND: Overnight transfusions have been associated with higher transfusion risk than transfusions during the day. The aim of the study was to evaluate the transfusion status at our hospital and to help provide plans for overnight transfusions. METHODS: All blood products, including red blood cell products (RBC), fresh frozen plasmas (FFP), and all platelet products (PLT) issued between January 2013 and December 2014 were included. Night1 (5 pm∼8 am) and Night2 (8 pm∼8 am) were defined as overnight, and all issued bloods (IB) were analyzed in accordance with the issued time, ordered medical departments, and the reason of transfusion. RESULTS: The total unit number of IB at Night1 (Night2) was 53,483 (38,224), and it consisted of 44.4% (31.7%) total IB; 53.2% (39.6%) FFP; 46.8% (33.4%) RBC; and 39.3% (27.6%) PLT. The IB ordered from the departments of trauma & acute care surgery and emergency medicine consisted of 40% IB. The 80.9% RBC, 53.1% FFP and 70.2% PLT could be considered as appropriate for overnight transfusion. CONCLUSION: Due to the characteristics of our hospital with many trauma patients, the percentage of IB during an overnight period in our hospital was higher than those in other countries, and the rate of appropriate reason for RBC transfusion was also higher. However, as inappropriate overnight transfusions may have been still performed, education for medical staffs and appropriate policies for overnight transfusion could be helpful in reducing inappropriate transfusion.

Optimum Conditions for the Preparation of Red Blood Cell Suspensions for ABO Antibody Titration

BACKGROUND: There is significant inter-laboratory variation in the ABO antibody (Ab) titer levels of blood samples because a standardized method has not yet been developed. The aim of this study was to identify the best conditions for the preparation of the red blood cell (RBC) suspensions so as to aid the development of a standard ABO Ab titration method. METHODS: Serum samples from apparently healthy adults and RBCs from three different sources (residual EDTA blood from healthy adults, donor blood in citrate-phosphate-dextrose-adenine-1 [CPDA-1], and a commercially available RBC reagent) were used for Ab titrations. We measured the titers for each blood group under various conditions, including the time period of storage (days), the ratio of serum to RBC volume, and the RBC sources. The techniques for room temperature incubation and the indirect antiglobulin test were used for the tube and the gel card test. RESULTS: A storage period of 6 to 7 days significantly affected the Ab titers. Samples with 3% RBCs in a 1:1 serum to RBC volume ratio had significantly lower Ab titers than those with 2% RBCs in a 1:1 ratio or those with 3% RBCs in a 2:1 ratio. There were no significant differences in the Ab titers of RBCs from different sources. CONCLUSIONS: To reduce inter-laboratory variations in ABO Ab titrations, using RBC suspension within five days of storage and applying ratio of serum to RBC volume to 2:1 with 3% RBC in the tube test will be helpful when using home-made RBC suspension.

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 1x10(12)/L and 2x10(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 2x10(12)/L than 1x10(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 1x10(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.

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.

Methods for Flow Cytometric Analysis of T Cell Subsets in HIV-infected Patients: 2-Color versus 4-Color

BACKGROUND: Blood CD4+ T-lymphocyte (T4) count is a major clinical marker for the diagnosis and management of AIDS, and flow cytometry is considered the gold standard for T4 enumeration. Our aim was to compare the 2-color and 4-color flow cytometric methods for T-cell subset analysis in HIV-infected patients. METHODS: T-cell subsets such as T3, T4, T8, and CD3+CD4-CD8- double negative T cells (DN T) were analyzed from the whole blood of 40 HIV-infected patients by using both 2-color and 4-color methods on a Cytomics FC500 analyzer. Statistical analyses using simple linear regression, paired t-tests, and Bland-Altman plots were performed. RESULTS: The measured T3 (%), T4 (%), T4 (/microL), T8 (%), T8 (/microL), and DN T (%) differed significantly between the 2 methods (P<0.05), whereas the T4/T8 ratio did not. T3 (%), T4 (%), T4 (/microL), T8 (%), T8 (/microL), and T4/T8 measured by the 2 methods showed good correlation, with correlation coefficients above 0.96, whereas DN T (%) did not. The mean differences in T4 (%) and T8 (%) were 0.39% (limit of agreement (LoA), -1.64~2.43) and 1.26% (LoA, -3.37~5.89), respectively. CONCLUSIONS: Although there were statistically significant differences in the T cell subsets measured between the 2 methods, the differences were minor, and the 2 methods showed good correlation. As confirmed in this study, DN T (%) estimated by the 2-color method is lower than the actual value. We suggest that although the 2 methods can be used interchangeably, the 4-color method is recommended for the analysis of some specific subpopulations such as DN T (%).

A Case Report of Mycobacterium abscessus Peritonitis in a Patient on Continuous Ambulatory Peritoneal Dialysis / 대한임상미생물학회지

Mycobacterium is an uncommon cause of peritonitis in patients receiving peritoneal dialysis (PD), and the incidence of nontuberculous mycobacterium (NTM) peritonitis is even rarer since the majority of mycobacterial peritonitis cases are caused by Mycobacterium tuberculosis. However, NTM peritonitis has been known to result in a high mortality rate with delayed diagnosis and treatment. In this study, we report a case of Mycobacterium abscessus peritonitis in a 52-year-old male under continuous ambulatory peritoneal dialysis (CAPD).