• Korean Journal of Clinical Laboratory Science
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• v.52 no.2
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• pp.98-104
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• 2020

Thalassemias are considered important health issues throughout Iraq, involving its Kurdistan region. This disorder, particularly its major form, needs lifelong regular transfusions. But this form of medical care is associated with various complications including red cell alloimmunization and autoimmunization. This study determined the frequency and associations of alloimmunization among multi-transfused patients with β-thalassemia major. The subjects were 204 patients who were registered at a thalassemia care center in Sulaymaniyah-Iraqi Kurdistan. The patients' records were analyzed, their red cells were phenotyped for ABO/RhD antigens using the gel card method, and irregular antibody screening/identification was performed using the standard tube method. Alloantibodies were detected in 5.8% of the patients, while DAT was positive in 4% of the patients, which indicated autoantibodies. The identified alloantibodies were anti-E (2.4%), anti-C (1.4%), anti-e (1%), and anti-K (1%). A patient's age at the start of transfusion (>2 years) (P=0.042) and a positive history of transfusion reactions (P=0.003) were correlated with a significantly higher rate of alloantibody formation. From the results of our study, we conclude that measures to decrease the development of alloantibodies may incorporate matching for Rhesus and Kell systems and early induction of blood transfusions.

• Biomedical Science Letters
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• v.12 no.1
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• pp.35-42
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• 2006

Alloimmunization to red blood cell (RBC) antigens may cause a delayed hemolytic transfusion reactions (DHTR) and a delayed serologic transfusion reactions (DSTR). In the present study, the frequency of alloimmunization and its clinical significance were evaluated. Also, transfusions were correlated with antibody formation. Alloimmunization rate was 0.63%. Alloimmunization rate in multiple transfused patients was 24.5%. The most common clinically significant alloantibodies of alloimmunized patients were found to be Rh antibodies (52.6%). Nine patients out of 38 (23.7%) became undetectable after the first detection. To be positive at antibody screening test after RBC transfusion was mean transfused numbers: 3.7 units, mean transfused periods: 56 days, mean transfused frequencies: 1.7 times. The results from antibody specificity and RBC transfusions were comparatively analyzed and it shows that Rh system antibodies were longer than other antibodies (P<0.05). In case of disease group, malignant diseases was longer than other diseases (P<0.05). In order to prevent the formation of RBC alloimmunization, irregular antibody screening tests were performed at propriety intervals in multiple transfused patients.

• Journal of Genetic Medicine
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• v.7 no.1
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• pp.1-8
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• 2010

Hemophilia A is a sex-linked recessive coagulation disorder associated with diverse mutations of the factor VIII gene and a variety of phenotypes. The type of mutation involved dictates the activity of factor VIII, and in turn the severity of bleeding episodes and development of alloantibodies against factor VIII (inhibitors). Missense mutations are the most common genetic risk factors for hemophilia A, especially mild to moderate cases, but carry the lowest risk for inhibitor development. On the other hand, intron 22 inversion is the most common mutation associated with severe hemophilia A and is associated with high risk of inhibitor formation. Large deletions and nonsense mutations are also associated with high risk of inhibitor development. Additional mutations associated with hemophilia A include frameshift and splice site mutations. It is therefore valuable to assess the mutational backgrounds of hemophilia A patients in order to to interpret their symptoms and manage their health problems.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.1
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• pp.36-40
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• 2016

Red blood cell (RBC) alloimmunization results from genetic disparity of RBC antigens between donor and recipients. The discrepancy of RBC antibody screening test occurs when the results of red cell tests do not agree with those of the serum test. In order to select the proper blood units for transfusion, clarification of the cause of discrepancies is essential. The RBC antibody screening test is an easy, quick, and reliable method for detection of clinically significant antibodies. Antibody screening and identification is recommended prior to transfusion to determine whether there is blood group incompatibility. We reported that phenotyping for E, D, M, E+c, and C+e antibody screening test should be extended. Therefore, these results indicate that anti-D and anti-E alloantibodies were major risk factors for haemolytic disease of the newborn or delayed haemolytic transfusion reactions in this study population. We suggested that its antibody screening be adapted to blood safety interventions. Targeted screening of selected recipients at risk offers less value than universal antibody screening, and more research is needed to determine the real incidence of this national condition.

• Korean Journal of Clinical Laboratory Science
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• v.45 no.4
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• pp.164-169
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• 2013

Red cell alloantibodies other than naturally occurring anti-A or anti-B are called unexpected red cell antibodies, and can be detected by performing an antibody screening. The frequency and distribution of unexpected antibody identified in Asan Medical Center were analyzed. We investigated a total of 135,238 cases of antibody screening test in AMC for 3 years from 2010 to 2012. Using column agglutination techniques, antibody identification tests were performed for the cases with positive antibody screening. Among 135,238 cases, 854 (0.6%) cases showed positive results of antibody screening test. In the order of frequency, 284 (33.3%) anti-Rh, 89 (10.4%) anti-MNS, 62 (7.3%) anti-Lewis, 34 (4.0%) anti-Kidd, 10 (1.2%) anti-Duffy, and 9 (1.1%) anti-P were identified. Multiple antibodies were detected in 199 (23.3%) cases. Among 381 subjects investigated for transfusion history, 299 (78.5%) had history of transfusion while 82 (21.5%) had unknown history. Thus the incidence of unexpected antibody was higher in the group with history of transfusion than the group without (p<0.001). Also, among 435 subjects investigated for the history of pregnancy, 46 (10.6%) had no history while 389 (89.4%) had history of pregnancy, showing higher incidence of unexpected antibody in the group with history of pregnancy than the group without pregnancy (p<0.001). Evaluated amounts and frequency of antigen exposure due to transfusion and pregnancy is suggested to increase the frequency of identification of unexpected antibody.

• The Korean Journal of Blood Transfusion
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• v.29 no.3
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• pp.320-327
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• 2018

A 72-year-old man with general weakness visited the outpatient clinic of the hematology department. The patient had been treated under the diagnosis of autoimmune hemolytic anemia for 2 years. His hemoglobin level at the time of the visit was 6.3 g/dL, and a blood transfusion was requested to treat his anemia. The patient's blood type was A, RhD positive. Antibody screening and identification test showed agglutination in all reagent cells with a positive reaction to autologous red blood cells (RBCs). He had a prior transfusion history with three least incompatible RBCs. The patient returned home after receiving one unit of leukoreduced filtered RBC, which was the least incompatible blood in the crossmatching test. After approximately five hours, however, fever, chills, dyspnea, abdominal pain, and hematuria appeared and the patient returned to the emergency room next day after the transfusion. The $anti-Fy^a$ antibody, which was masked by the autoantibody, was identified after autoadsorption using polyethylene glycol. He was diagnosed with an acute hemolytic transfusion reaction due to $anti-Fy^a$ that had not been detected before the transfusion. In this setting, it is necessary to consider the identification of coexisting alloantibodies in patients with autoantibodies and to become more familiar with the method of autoantibody adsorption.