Risk factors analysis of blood type unexpected antibody in large sample of inpatients / 中国输血杂志

【Objective】 To observe and analyze the detection results of blood type unexpected antibody and its risk factors in inpatients, so as to provide reference for promoting the safety of clinical blood transfusion. 【Methods】 Clinical data of 22 800 inpatients were collected retrospectively and unexpected antibody screening was performed by microcolumn gel method and saline method. According to the screening results, the inpatients were divided into positive group (n = 62) and negative group (n = 22 738). Clinical data of the two groups were collected and analized by univariate analysis, and specificity identification of unexpected antibody was performed in the positive group. The specific distribution characteristics of antibody were statistically analyzed, and the risk factors of unexpected antibody were analyzed by binary logistic regression. 【Results】 Among the 22 800 inpatients, the yield rate of unexpected antibody was 0.27% (62/22 800), with Rh, MNS, Lewis, Kidd blood group antibody, mixed antibody, autoantibodies and others accounted for 40.32% (25/62), 14.52% (9/62), 6.45%(4/62), 1.61%(1/62), 20.97%(13/62), 6.45%(4/62) and 9.68%(6/62), respectively. Univariate analysis showed that there were significant differences in gender, age, pregnancy history, blood transfusion history, blood transfusion frequency and disease type between the positive group and the negative group by chi-square test (χ2 = 11.142, 6.994, 12.453, 4.762, 5.493, 92.381, all P<0.05), while there was no significant difference in nationality (χ2 = 3.719, P>0.05 ) . Binary logistic regression analysis showed that female, age >60 years old, with history of blood transfusion, number of blood transfusion >3 times, history of pregnancy, solid tumor and blood diseases, severe internal medical diseases were independent risk factors for unexpected antibody(P<0.05) . 【Conclusion】 For patients who need blood transfusion, especially those with the above risk factors, conducting unexpected antibodies screening and identification before transfusion, avoiding corresponding antibodies and selecting antigen-negative blood for cross-matching were suggested to ensure the effectiveness and safety of clinical blood transfusion.

Unexpected antibody distribution among tumor patients: analysis of 111 483 cases / 中国输血杂志

【Objective】 To analyze the distribution of unexpected antibodies in tumor patients retrospectively and explore the clinical significance. 【Methods】 Unexpected antibody screening was performed on inpatients with blood preparation and blood transfusion in our hospital from January 2004 to December 2022, with 1 176 cases tested positive, and the types of unexpected antibodies and distribution characteristics were statistically analyzed. 【Results】 Unexpected antibodies were screened in 1 176 cases, with the positive rate at 1.05% (1 176/111 483). The unexpected antibodies were mainly anti-E 16.33%(192/1 176), anti-M 7.99% (94/1 176), anti-Mur 5.70% (67/1 176) and anti-Lea 4.76% (56/1 176). Among the 1 176 cases, gastrointestinal tumors accounted for 27.99% (329/1 176), gynecological tumors accounted for 24.84% (292/1 176), respiratory tumors accounted for 16.67% (196/1 176) . 【Conclusion】 The influencing factors of unexpected antibodies in tumor patients were disease type, blood transfusion history and blood type. Therefore, it is necessary for clinical departments to carry out unexpected antibody screening and perform Rh blood type matched transfusion for tumor patients to avoid alloantibody production.

Identification of immune hemolytic transfusion reaction and exploration of transfusion compatibility testing / 中国输血杂志

【Objective】 To analyze the causes of immune hemolytic transfusion reaction in one case, identify related antibodies, and explore transfusion compatibility testing. 【Methods】 ABO/Rh blood group identification, unexpected antibody identification of serum and diffusion fluid, direct antiglobulin test(DAT) and cross matching were conducted by saline method and/or microcolumn gel method. 【Results】 The patient′s blood group was O, and Rh phenotype was identified as DCCee. The DAT was negative, with strong anti-E antibody and weak anti-c antibody detected. Acute hemolytic transfusion reaction occurred in the patient after the last transfusion. 【Conclusion】 Currently, immune hemolytic transfusion reaction in China are mainly caused by Rh blood group system antibodies. The absence of unexpected antibody screening before blood transfusion and the weak anti-c antibody which resulted in missed detection of non compatibility in cross matching led to acute hemolytic transfusion reaction. It is recommended to conduct unexpected antibody screening before blood transfusion, and to collect blood sample for testing as soon as possible to improve the accuracy of DAT when acute hemolytic transfusion reaction is suspected.

Distribution and transfusion efficacy of unexpected antibody / 中国输血杂志

【Objective】 To investigate the clinical characteristics and antibody distribution as well as evaluate the transfusion efficacy in unexpected antibody positive patients. 【Methods】 A total of 12 235 patients from January 1, 2022 to March 31, 2023 who hospitalized in our hospital and applied for blood transfusion were selected, and those with unexpected antibody were included. The clinical data, including gender, age, diagnosis, blood type, history of transfusion and pregnancy were collected for antibody distribution analysis. Patients who received transfusion were grouped according to the DAT results and the components of red blood cells transfused, and the Hb values of each group before and after transfusion were compared. 【Results】 Among12 235 patients, 118 were positive for antibody screening, with a prevalence of 0.96%. The antibodies from Rh system were the most common (27.43%, 48/175), followed by MNS system (8.57%, 15/175) and Lewis system (6.29%, 11/175), mainly anti-E (18.29%, 32/175), anti-M (8.00%, 14/175) and anti-Lea (5.71%, 10/175). In addition, 62 transfused patients were divided into group A with suspended red blood cell transfusion and group B with washed red blood cell transfusion for positive DAT, and group C for negative DAT. Hb values (g/L) pre- and post-transfusion were 59.19±15.67 vs 77.52±15.09 in group A, 56.35±14.08 vs 74.44±15.63 in group B, 56.00±12.06 vs 75.00±4.73 in group C, respectively. The Hb values of post-transfusion for three groups were all higher than those of pre-transfusion (P<0.05). 【Conclusion】 Anti-E from Rh system is the most common antibody in patients with unexpected antibody. Appropriate red blood cells transfusion with Hb increases by an average of 6-7 g/L per 1 U of red blood cells indicating good transfusion efficacy. For positive DAT patients, transfusion of suspended red blood cell is feasible.

Results analysis of unexpected antibody screening for blood donors and cost comparison of two detection modes / 中国输血杂志

【Objective】 To establish a routine screening method for unexpected antibodies of blood donors, analyze the results of centralized screening for unexpected antibody of blood donors in the blood center, and compare the cost of centralized and decentralized screening modes. 【Methods】 A total of 35 591 blood donors were screened for unexpected antibodies from March 31, 2021 to July 31, 2021, using microcolumn gel method. Unexpected antibody screening reactive samples were further confirmed by the Transfusion Research Institute of Shenzhen Blood Center, and the demographic characteristics were further determined through the analysis of unexpected antibody positive population. The direct cost and indirect cost of centralized and decentralized unexpected antibody screening mode were compared. 【Results】 Forty unexpected antibody positive samples were confirmed in Shenzhen, with the positive rate at 0.11%(40/35 591), among which MNS, Rh and Lewis system accounted for 35% (14/40), 32.5% (13/40) and 17.5% (7/40), respectively. Males and females accounted for 45% (18/40) and 55% (22/40), respectively (P0.05). Unexpected antibody screening in a centralized way saved about 1.16 million yuan per year. 【Conclusion】 It is necessary to carry out unexpected antibody screening for all blood donors, and centralized screening is more economical than decentralized screening.

Study on the safety of homotype transfusion of military blood donors with negative unexpected antibodies / 中国输血杂志

【Objective】 To analyze the safety of homotypic transfusion in military donors with negative unexpected antibody. 【Methods】 Blood samples (4 mL/person)of eligible military blood donors from November 2018 to October 2019 in our hospital (also working as forces blood station) were conducted for RBC antigen typing, unexpected antibody screening, direct antiglobulin test and cross-match test using microcolumn gel technology, and the compatibility of homotype blood samples was statistical analyzed. 【Results】 A total of 1 577 samples from eligible military blood donors were collected, including A RhD (+ ), B RhD (+ ), O RhD (+ ) and AB RhD (+ ), accounting for 31.39% (495/1 577), 34.37% (542/1 577), 24.10% (380/1 577) and 10.15% (160/1 577), respectively. Six samples presenting positive unexpected antibodies (0.38%, 6/1 577) were screened out, and a total of 7 141 cross-matching tests were performed on 1 571 unexpected antibody negative samples, including A RhD (+ ) [37.36% (2 668/7 141)], B RhD (+ ) [34.81% (2 486/7 141)], O RhD (+ ) [17.71% (1265/7 141)] and AB RhD (+ ) [10.11% (722/7 141)]. There was only 1 case of incompatible cross-matching presented between other donors and clinical patients, and the direct antiglobulin test was 1+ , therefore suspended red blood cells of the donor were scrapped. 【Conclusion】 There was high compatibility and good security of homotype transfusion of military blood donors with negative unexpected antibody.

Unexpected antibody screening of thalassemia children in Yunnan Province and the blood transfusion strategies / 中国输血杂志

【Objective】 To study the yielding rate and distribution of unexpected antibodies in blood transfusion children with thalassemia in Yunnan province, and to explore the blood transfusion strategies. 【Methods】 From January 2016 to December 2021, 298 children with thalassemia, who received blood transfusion treatment in Kunming, Xishuangbanna, Wenshan, Dehong, Yuxi and Baoshan hospitals across Yunnan Province, were selected. The unexpected antibodies of blood plasma were screened by microcolumn gel card. The samples with positive antibodies were identified for alloantibody specificity. 【Results】 Unexpected antibodies were yielded in 67 out of 298(22.48%) transfused children with thalassemia. The positive rates of unexpected antibodies in boys and girls were 16.55%(24/145) and 28.10%(43/153), respectively. The positive rates of unexpected antibodies in Han, Dai, Zhuang, Yi, Bulang, Jinuo and Miao people were 14.06%(18/128), 30.80%(32/104), 35.71%(10/28), 36.36%(8/22), 50.00%(4/8), 60.00%(3/5)and 66.67%(2/3), respectively, with statistically significant differences between each other. The positive rate of unexpected antibodies in ethnic minorities was higher than that in Han. The positive rates of unexpected antibodies in children who received the first transfusion at birth-one year old, 1~3 years old, 3~6 years old and above 6 years old were 12.50%(3/24), 10.14%(7/69), 24.54%(40/163)and 40.48%(17/42), respectively. The positive rates of unexpected antibodies in children with first transfusion after 3 years old were significantly higher than those before 3 years old. The positive rates of unexpected antibodies in children with one transfusion, 1~3, 3~10, 10~20 and more than 20 transfusions were 4.76%(1/21), 12.07%(7/58), 23.71%(23/97), 28.16%(29/103)and 36.84%(7/19), respectively, with statistically significant differences between each other. The number of blood transfusions was positively correlated with the unexpected antibody yielding. The yielding rate of unexpected antibodies in children with α thalassemia, βthalassemia, δ+ βthalassemia and untyped thalassemia was 7.50%(3/40), 17.62%(34/193), 53.70%(29/54)and 9.09%(1/11), respectively(P<0.05). The yielding rate of unexpected antibodies in transfused children with δ+ βthalassemia was the highest. And 57 unexpected antibodies of Rh blood group system were yielded, 6 anti-M antibodies, 2 anti-N antibodies and 2 undetermined. 【Conclusion】 The positive rate of unexpected antibodies in transfused children with thalassemia in Yunnan province is high. Routine antibody screening should be carried out for transfusion children with thalassemia, and blood units, compatible with ABO, Rh and MNS typing results, should be selected to ensure the safety and effectiveness of clinical blood use.

Reduction Plan of ‘Undeterminable’ in the Unexpected Antibody Screening by the Microcolumn Agglutination Automated Instrument / 대한수혈학회지

BACKGROUND: Among the results of an unexpected antibody screening test using IH-1000, ‘undeterminable’ results can be obtained. Repeated tests not only use reagents and consumables but also cause a turnaround time delay. Therefore, it is important to reduce the ‘undeterminable’ results and to determine the effects. METHODS: From January to early June, 2016, 2,872 cases/259,455 tests (1.11%) of ‘undeterminable’ were detected in the screening test. The factors considered to affect the ‘undeterminable’ were classified into four categories: ① reagent, ② consumables, ③ inspection environment & specimen, and ④ enhancing the equipment management. For data comparison, a chi-square test was conducted (95% confidence interval, 0.05 significant level). RESULTS: The incidence of ‘undeterminable’ cases decreased from 1.11% before management to 0.66% (P < 0.001) after Pool Cells management. The consumption of ‘LISS/Coombs Card’ decreased from 1.07% before management to 0.51% (P < 0.001) after management. By maintaining a clean inspection environment and strengthening sample management, the rate decreased from 1.11% before management to 0.66% (P < 0.001) after management. On the other hand, there was no difference in the incidence of ‘undeterminable’ between before and after IH-1000 management reinforcement. CONCLUSION: Among the factors predicted to affect the decrease in the incidence of ‘undeterminable’, the management of Pool Cells and keeping the inspection environment clean as well as improving sample management contributed the most to the reduced ‘undeterminable’. Improvements in the management of consumables, and removing dust from the inside of the equipment, had a positive impact. A continuous quality improvement theme has been adopted and it is helpful for managing and improving the predicted factors.

Delayed Hemolytic Transfusion Reaction with Alloimmunization of Rh Phenotype: A Two-Case Study / 대한수혈학회지

Delayed hemolytic transfusion reaction is difficult to prevent using an unexpected antibody test performed prior to transfusion, and unlike acute hemolytic transfusion reaction, it occurs a few days after blood transfusion. Hence, determining the reason for delayed hemolytic transfusion reaction may be a tim-consuming task for clinicians Here, we report our experience of two cases of delayed hemolytic transfusion reaction as a result of the unexpected antibody production to Rh blood group antigens after transfusion. The first patient with a history of transfusion during admission was identified as having anti-E and anti-C antibodies according to the antibody identification test at the time of re-admission. The second patient who had chronic blood transfusion due to cancer treatment was found to have anti-C antibody. Both patients received transfusion of Rh antigen-compatible RBC units only after unexpected antibody development. However, like both cases, patients receiving continuous blood transfusion should be considered for a routine Rh phenotype test.

Revisiting the Pre-transfusion Test: A Case of Acute Hemolytic Transfusion Reaction due to Multiple Alloantibodies of Anti-E, Anti-c, Anti-Jk(b) / 대한수혈학회지

We report a case of acute hemolytic transfusion reaction due to multiple alloantibodies. A 41-year-old male with multiple histories of transfusion was admitted for jaundice and oliguria after receiving two units of red blood cells in a local clinic. He showed acute renal failure and disseminated intravascular coagulation. Direct Coombs test was negative and antibody screening test showed strong positive results. Anti-E, anti-c, and anti-Jk(b) antibodies were identified in two panels of unexpected antibody assays. Acute hemolytic transfusion was diagnosed, and he was discharged after 1 month of supportive treatment. Unexpected antibody detection tests, including the antiglobulin phase, should be performed to prevent adverse transfusion reactions by unexpected antibodies. Better precision and quality control are necessary when performing pre-transfusion tests.

A Case Report of Anti-f(ce) Identified in a Patient with Pancreatic Cancer / 대한수혈학회지

Anti-f(ce) is a rare unexpected antibody against the ce(f) antigen. The aim of this study is to report a second case of anti-f(ce) identified in a patient. A 66-year-old-male with pancreatic cancer received percutaneous transhepatic biliary drainage. During pretransfusion tests, anti-f(ce) was identified. He had a history of multiple transfusions and was transfused with 2 units of antiglobulin crossmatch compatible RBCs without any adverse reactions. To confirm that the antibody was specific for ce(f) antigen, we crossmatched the patient's serum with RhD-positive red cells of Rh phenotype DcE, DCcEe, DCce, and DCe; all results were negative. Conversely, a crossmatch with RhD-negative red cells of Rh phenotype ce, Cce, and cEe, showed positive results for Rh phenotype ce and cEe red cells. Among the four reports that confirmed anti-e, we discovered the possibility of co-existence of anti-C or misidentification of anti-Ce as anti-e. Therefore, when antibodies against Rh antigens are identified, the possibility of co-existence of antibodies against compound antigens should be considered. Using unexpected antibody identification panel that ce(f) antigen positive red cells are marked is recommended for sensitive detection of anti-f(ce).

Usefulness of Additional LISS/Coombs Card Test with Enzyme-Treated Red Cells in Detecting Anti-Kidd Antibodies Not Detectable by NaCl/Enzyme Card Test Alone / 대한수혈학회지

BACKGROUND: Detection of anti-Kidd antibody is important because of its clinical significance. If detection is difficult due to weak serological reactivity or dosage effect, use of an enzyme method could be helpful. However, despite use of an enzyme method, we still observed weak reactivity of anti-Kidd antibody. METHODS: All identified anti-Kidd antibody cases from Jan 2012 to Aug 2015 in Asan Medical Center were reviewed. Antibody identification test was performed using the column agglutination technique using Bio-Rad ID-DiaPanel with LISS/Coombs card, Bio-Rad ID-DiaPanel-P with NaCl/Enzyme card, and ID-DiaPanel-P with LISS/Coombs card. The test results were compared. RESULTS: Sixty cases of anti-JK(a) or anti-Jk(b) were detected and tested by enzyme method. Among them, 34 (56.6%) cases showed strengthened reactivity using the ID-DiaPanel-P with NaCl/Enzyme card method. However, 26 (43.4%) cases showed weakened reactivity. Of these, 13 cases that could be tested by an additional method using ID-DiaPanel-P with LISS/Coombs card containing anti-IgG and anti-C3d showed successfully strengthened reactivity. CONCLUSION: The reactivity of anti-Kidd antibodies that was not strengthened using ID-DiaPanel-P with NaCl/Enzyme card method could be successfully strengthened by use of the ID-DiaPanel-P with LISS/Coombs card.

Performance Evaluation of Unexpected Antibody Screening Test Including Di(a) Cell Using 3% Surgiscreen Sub-Code D in Korean Multi-Transfused Patients / 대한수혈학회지

BACKGROUND: The Dia antigen has been found to have a relatively higher incidence among Korean populations. However, the current popular antibody screening panels contain no Dia positive cells. To prevent hemolytic transfusion reaction, screening for unexpected antibody plus screening for Dia positive cells should be performed. In this study, we evaluate the performance of the 3% Surgiscreen Sub-code D (Ortho-Clinical Diagnostics, USA) manufactured as a 3-cell panel including Dia cell versus the ID-DiaCell I-II (DiaMed, Switzerland) as a 2-cell panel plus ID-DiaCell Dia+ (DiaMed, Switzerland) in screening for irregular red blood cell alloantibodies. METHODS: From December 13, 2013 to April 24, 2014, we tested the 3% Surgiscreen by the AutoVue Innova system and the ID-DiaCell in parallel to evaluate reagent sensitivity in detecting irregular antibodies in multi-transfused patients' plasma or serum. Identification of unexpected antibody tests was performed for positive screening results. RESULTS: Antibody-positive rates were 4.2% (79/1885) and 4.6% (87/1885) for antibody screening with the 3% Surgiscreen and the ID-DiaCell, respectively. Among the 1885 samples, 1875 (99.5%) showed concordant results between the 2 methods, while 10 results differed. From the 10 discrepancies, 1 result was positive only on the 3% Surgiscreen. The prevalence of anti-Dia antibody was 10.1% and 9.2% in the 3% Surgiscreen and the ID-DiaCell, respectively. CONCLUSION: The 3% Surgiscreen manufactured as 3-cell showed a high concordance rate ompared to standard methods. The prevalence of anti-Dia showed no difference between the 2 reagents.

Analysis of Unexpected Antibodies Detected in Children: A Single Center Study for 7 Years / 대한수혈학회지

BACKGROUND: Frequency and distribution of unexpected red cell antibodies vary according to study population and method of antibody detection. The frequency and specificities of unexpected red cell antibodies were analyzed and compared in adults and children. METHODS: We analyzed the results of antibody screening and identification tests performed from November of 2008 to June of 2015 at Pusan National University Yangsan Hospital. A commercially available three-cell antigen panel, DiaCell I, II and Dia (DiaMed, Murten, Switzerland) for antibody screening, LISS/Coombs and NaCl/Enzyme card and the ID-Dia Panel (DiaMed, Murten, Switzerland) for antibody identification were used. RESULTS: Among the 91,145 adults, 1,804 (1.97%) had positive results for antibody screening test and 11,457 children, 447 (3.90%) had positive results. In adults, the most frequently detected unexpected antibody was anti-E (103 samples), followed by by anti-E&c (51 samples), anti-Lea (27 samples), and anti-Dia (27 samples). In children, anti-M (7 samples), anti-E&c (5 samples), anti-E (4 samples), and anti-D (4 samples) were most frequently detected. Among 9 pediatric patients with anti-E or anti-E&c, 5 patients were proven as hemolytic disease of the fetus and newborn. CONCLUSION: In this study, the positive rate of unexpected antibody screening in children was higher than in adults. Distribution of unexpected antibody differed between children and adults. It may be related to the frequent cardiac surgery performed in children at our hospital. No studies have been conducted in children. Our research may provide data for the frequency and characteristics of red cell antibodies in children.

Eleven Years' Experience with Unexpected Antibody Screening Tests Including a Di(a) Cell in Transfusion Candidates / 대한수혈학회지

BACKGROUND: The Di(a) antigen has been detected with a relatively higher incidence among the Korean and Southeast Asian population. A 'Type and Screen' procedure is recommended for efficient transfusion, therefore, we perform antibody screening tests using antibody screening panels containing a Di(a) cell. The purpose of this study was to report on the experience of unexpected antibody screening test including a Di(a) cell in the Korean population. METHODS: We analyzed the results of antibody screening testing and identification performed during the recent 11-year period from January 2002 to December 2012. A commercially available three-cell antigen panel (Diacell I, II, Di(a); DiaMed, Murten, Switzerland) was used for antibody screening. Antibodies were identified using a LISS/Coombs gel card and NaCl/Enzyme card, using the DiaMed-ID system (DiaMed, Murten, Switzerland). RESULTS: The frequency of unexpected antibodies was 1.23% (1,918/156,161); the most frequently detected antibodies were anti-E (292 samples), followed by anti-E,c (127 samples), anti-Le(a) (103 samples), and anti-Di(a) (91 samples). CONCLUSION: Results of this study showed that the most identified unexpected antibodies were clinically significant, and, in particular, anti-Di(a) antibodies are detected frequently in the Korean population. Thus, unexpected antibody screening test including a Di(a) cell is thought to be helpful in Korea for safe transfusion.

Unexpected red cell antibody detection by conditional combination of LISS/Coombs and NaCl/Enzyme gel tests at a tertiary care hospital in Korea: A 5-year study

BACKGROUND: A combination of the LISS/Coombs and enzyme methods is recommended for identifying unexpected antibodies. However, many laboratories in which tests are to be performed within the limits of medical fees covered by insurance, use only the LISS/Coombs method because the permissible medical fee is low as compared to the price of reagents required for both methods. The NaCl/Enzyme gel is used as a secondary assay when the LISS/Coombs gel test yields inconclusive results. We compared the frequency of unexpected antibody identified by LISS/Coombs gel with that obtained by the conditional combination of LISS/Coombs and NaCl/Enzyme gels. We aimed at establishing evidence-based guidelines for antibody testing. METHODS: From June 2007 to June 2012, antibody screening was performed for 69,986 samples; subsequently, antibodies were identified in samples showing positive screening results. These initial screenings and identifications were performed using the LISS/Coombs gel. We considered the results "inconclusive" when specific antibodies were not identified or reactions were too weak for accurate interpretation. For the inconclusive samples, we subsequently used NaCl/Enzyme gels. RESULTS: The overall detection rate of unexpected antibodies was 1.23%. Among the samples analyzed using NaCl/Enzyme gels, 40.2% showed results different from those obtained using LISS/Coombs gels. Moreover, 41.9% of samples with nonspecific reactions in LISS/Coombs gels showed clinically significant Rh or Kidd antibodies with NaCl/Enzyme gels. CONCLUSION: Considering both patient safety and cost effectiveness, we recommend the use of conditional combination of LISS/Coombs and NaCl/Enzyme gels for antibody detection, especially in laboratories that must perform tests within an established budget.

External quality assessment in blood group serology in the World Health Organization South-East Asia Region.

Background: The quality of blood transfusion services (BTS) is essential for the treatment of patients who need blood or blood products. BTS involve several steps, including the acquisition of the donor’s blood, blood grouping, unexpected antibody screening, blood storage, transfusion, etc. There is a need to check the effectiveness of all elements in the BTS can be assessed and monitored by an external quality assessment. Aim: To assess and evaluate the performance of ABO and Rh(D) blood grouping and unexpected antibody screening of the selected World Health Organization (WHO) South-East Asia Region Member country laboratories. Methods: WHO Collaborating Centre on Strengthening Quality of Health Laboratories (Thailand) organized a regional external quality assessment scheme for blood group serology (REQAS-BGS) between 2002 and 2008 for laboratories in countries of the WHO South-East Asia Region. Test items for ABO and Rh(D) blood groupings and unexpected antibody screening and identification were distributed three cycles per year to BTS laboratories in Bangladesh, Bhutan, India, Indonesia, Maldives, Myanmar, Nepal, Sri Lanka and Thailand. By the end of the project, a total of 20 BTS laboratories had participated for differing lengths of time. Results: It was found that 87.5%, 93.3%, 81.3%, 92.3%, 100% and 87.5% of laboratories returned the test results in 2002, 2003, 2004, 2006, 2007 and 2008, respectively. Laboratories with excellent quality or a trend of quality improvement for ABO and Rh(D) blood grouping, unexpected antibody screening and identification during the six years were 60% (12/20), 50% (10/20), 52.9% (9/17) and 81.8% (9/11), respectively. At the initiation of the scheme, most laboratories were using substandard methods for ABO and Rh blood groupings, i.e. performing only direct blood grouping alone but subsequently adopted the standard methods, i.e. performing both direct and reverse blood groupings. Conclusion: REQAS-BGS in South-East Asia countries has been useful for assessing, monitoring and improving the quality of testing. Challenges such as high costs and regulatory requirements for international shipment of blood samples could be solved by amending the regulation(s) for shipment, or establishing a national EQAS.

The Frequency of Unexpected Antibodies and Clinical Characteristics of Transfusion Candidates in a General Hospital During the Past 12 Years / 임상검사와정도관리

BACKGROUND: Unexpected antibodies are an important cause of hemolytic transfusion reaction. Thus, unexpected antibody screening and identification tests should be performed before every transfusion. We evaluated the frequency and distribution of unexpected antibodies and the clinical characteristics of patients in a Korean secondary general hospital with 745 beds in the past 12 years. METHODS: Between March 2000 and October 2011, unexpected antibody screening and an identification test using the Bio-Rad ID-System (Bio-Rad, USA) were performed in 72,600 patients. RESULTS: Of the 72,600 patients, 467 (0.64%) showed positive results for antibody screening tests. Among them, alloantibodies were identified in 324 (69.4%) patients and the types of alloantibodies were not identified in 64 (13.7%) patients. Autoantibodies were detected in 71 (15.2%) patients and panagglutination reactions were detected in 8 (1.7%). Of the 467 cases, 164 (35.1%) had a history of transfusion in our hospital. Among the 324 patients in whom alloantibodies were identified, anti-E (37.3%), anti-Lea (16.7%), anti-E and anti-c (14.8%), anti-C and anti-e (5.6%), anti-Leb (4.9%), anti-D (4.6%), anti-Jka (3.1%), anti-S (2.5%), and anti-M (1.9%) were detected. In 41 of the 324 (12.7%) of these patients, the types of antibodies were identified with the NaCl/Enzyme gel test but not with the LISS/Coombs gel test. CONCLUSIONS: Among the 467 patients, 130 (27.8%) in whom unexpected antibodies were detected, were scheduled for surgery. Because 101 of these 130 patients (77.7%) were unimmunized, unexpected antibody screening may be important in secondary hospitals with patients who do not have a detailed transfusion history. We identified Rh, P, and Lewis group antibodies more efficiently with a combination of the LISS/Coombs gel test and the NaCl/Enzyme gel test.

Frequency of Detection of Unexpected Antibodies in Transfusion Candidates at a Secondary Hospital in Gyeongbuk Province / 대한수혈학회지

BACKGROUND: Antibody screening and identification tests are indispensable tools for protecting patients from acute hemolytic transfusion reaction. The column agglutination method has been widely used because of its simplicity and superiority to other methods for detecting warm antibodies. The purpose of this study was to analyze the frequency, distribution and clinical characteristics of unexpected antibodies found in transfusion candidates at a secondary hospital in Gyeongbuk Province, Korea. METHODS: The antibody screening tests were carried out with 9,275 sera samples using the column agglutination method from July 2009 to September 2011. The antibodies were screened and identified using the DiaMed-ID system (DiaMed, Murten, Switzerland). RESULTS: The positive rate for antibody screening tests was 0.5% (50/9,275). Unexpected antibodies were identified in 36 cases (0.4%). The most frequently detected antibody was anti-Lea in 15 cases (30%), followed by anti-Leb in 10 cases (20%) and anti-E in 8 cases (16%). Antibodies that remain unidentified were detected in 11 cases (22%). CONCLUSION: Compared with previous reports, this study demonstrated that the frequency and distribution of unexpected antibodies were no different than those found in general hospitals. This study may provide data for the frequency and characteristics of unexpected antibodies in a secondary hospital.

Screening and Identification of Unexpected Red Cell Antibodies by Simultaneous LISS/Coombs and NaCl/Enzyme Gel Methods

We evaluated the clinical usefulness of simultaneous LISS/Coombs and NaCl/Enzyme testing using the gel method for screening and identification of unexpected antibodies in 15,014 samples. When unexpected antibodies were detected by either screening test, those antibodies were identified using both the LISS/Coombs and the NaCl/Enzyme gel test. The positive screening rates of the LISS/Coombs, NaCl/Enzyme, and combined tests (excluding 25 autoantibody cases) were 0.48%, 1.29%, and 1.39%, respectively. Among the 57 samples positive by both screening methods, the antibodies in 19.3% could be identified only by the NaCl/Enzyme method. Among the 137 samples positive only by NaCl/Enzyme screening, 74.5% showed positive results in antibody identification only by the NaCl/Enzyme test, although 7.3% were also positive in the LISS/Coombs test. The NaCl/Enzyme method thus showed about threefold higher detection rates than the LISS/Coombs method, especially in screening for Rh antibodies, and higher exact identification rates and discriminatory power for identifying mixed antibodies. Addition of the NaCl/Enzyme method to routine laboratory procedures may detect and identify considerable numbers of significant antibodies that might be missed if only the LISS/Coombs method is used.