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Introduction: Beta Thalassemia is an inherited haemoglobin disorder characterized by reduced synthesis of beta globin chains.1 The most severe forms of AY-thalassemia major present within the first year of life with severe anaemia and failure to thrive.2 The haemoglobinopathies are major genetic problems in Pakistan. The purpose of this study was to determine the frequency of red cell alloantibodies and auto-antibodies in thalassemia major children receiving regular blood transfusions. It was a cross sectional survey. It was performed at The Children Hospital and Institute of Child Health Lahore in Dec.2009 May 2010.Subjects and Methods: 130 diagnosed patients of beta thalassaemia major from Children Hospital Lahore were selected. Blood grouping and direct antiglobulin test was performed in these patients. Alloantibody screening and identification tests were done using the 3 cell panel followed by 11 cell panel of Diamed.Results: Among the 130 patients 8.5% (n = 11) patients were diagnosed to have alloantibodies. Autoantibodies were detected in 2.3% (n = 3).Conclusion: Presence of red cell antibodies and red cell autoantibodies are frequent findings in transfused thalassaemic patients and should not be overlooked in patients with thalassaemia major receiving regular blood transfusion. Regular screening for red cell alloantibodies and autoantibodies would add towards the better management of these patients.

Key Words: Beta Thalassaemia Major Multiple blood transfusions Alloimmunization.


Beta Thalassemia is an inherited haemoglobin disorder characterized by reduced synthesis of beta globin chains.1 The most severe forms of AY-thalassemia major present within the first year of life with severe anaemia and failure to thrive.2 The haemoglobinopathies are major genetic problems in Pakistan. About 5 percent of the Pakistani population carries AY-thalassaemia and about 5250 infants with AY-thalassemia major are born annually.3 Regular blood transfusion every 3 to 4 weeks remains the treatment for most of the thalassaemia major patients4. Regular blood transfusion is associated with a number of risks and complications including iron overload transmission of infectious agents haemolytic transfusion reactions and alloimmunisation etc.5 There is a high probability that the donor will have red cell antigens not present in the recipient and it will result in alloimmunization. Similarly autoantibodies formed in these patients can complicate transfusions6. Alloimmunization is an immune response generated in an individual by a foreign antigen from a different individual of the same species.7 This type of sensitization results in difficulty in obtaining compati-ble blood transfusion reactions occasionally haemolysis and life threatening events.8 This study is designed to determine frequency of red cell alloantibodies and autoantibodies so that serious hazards because of immunization may be avoided by screening these patients for alloantibodies and autoantibodies.


A total 130 cases of Beta Thalassaemia Major diagnosed on High Performance Liquid Chromatography of all ages and both genders at Children Hospital Lahore were included in the study from outdoor patient department. An informed consent was obtained in all the cases from the parents of children and their demographic profile obtained.A 5 10 ml venous blood was collected. Blood grou-ping and direct antiglobulin test was performed on all samples. A poly specific coombs reagent wasused. Blood was allowed to clot serum was separated and stored in labeled test tubes. Red cell alloantibodies were detected using standard blood bank methods (saline albumin / LISS and coombs phases). A3cell antigen panel from Diamed was used to detect the anti-body by indirect anti-globulin test (IAT). Antibody identification was performed in antibody screening positive samples using 11 cell panel. A proper quality control of test was monitored.All data collected was entered and analyzed through statistical package SPSS version 17. Results of antibody screen and identification testing were analyzed on SPSS. The frequencies of blood groups alloantibodies and autoantibodies in selected patients were determined. Qualitative variables in this study such as gender blood group presence or absence of alloantibody and autoantibodies were expressed in terms of frequencies and percentages and presented as frequency distribution tables. Numerical variables like age were presented as means with standard deviation.


A total of 130 children were enrolled to determine the frequency of alloimmunization and autoantibodies in these patients presenting with Thalassemia major. All of them were receiving regular blood transfusion.58.5% (n = 76) patients were males and 41.5% (n = 54)were females (Fig. 1).

Table 1: Age distribution of the patients (n = 130).

###Age of the Patients###No. of Patients###% age


###6 10###56###43.1

###11 16###15###11.5


The patients were divided in 3 groups on the basis of age. First group from 1 5 years comprising of45.38% (n = 59) 2nd group from 6 10 years of 43.1%(n = 56) patients and 3rd group of 11 16 years having11.5% (n = 15) patients. Mean age was 6.28 3.18 (age range 1 16 years) (Table 1).Red cell alloantibodies were found in 8.5% (n = 11)patients. Among them 54.5% (n = 6) were males and45.4% (n = 5) were females (Table 2). Auto-antibodies were detected in 3 patients (2.3%) with increased hemolysis and difficulty in finding compatible blood in two patients. The mean age of patients who developed red cell alloantibody was 8.8 3.79. Age ranges from2 16 years. 3 patients were in group 1 (age 1 5) 6 in group 2 (age 6 10) and 2 in group 3 (age 11 16)

Table 2: Frequency of red cell Alloantibodies and auto-antibodies in thalassaemia major (n=130).

###Immunisation###No. of Patients###% age



Table 3: Frequency of ABO and RH Blood groups in thalassaemia patients.

Blood Group###Non-alloimmunized###Alloimmunized





Rh positive###82%###24%

Rh negative###18%###76%

Blood grouping of all patients included in this study were performed. Frequencies of different blood groups in both alloimmunized and non alloimmunized groups were calculated. Blood group O was the commonest in both groups followed by group B. Rh negative group is seen in76% of alloimmunized patients and Rh positive group is predominant in 82% of non alloimmunized patients (Table 3).Anti D Antibodies were detected in 2 patients one male and one female anti E in 5 patients 3 male and 2 females anti c in 1 female and anti K in 2 male and 1 female patients were identified. Anti Rh antibodies are72% of total alloantibodies and Kell group antibodies comprise 28%.Higher frequency of alloimmunization was seen in Rh negative patients. Male to female ratio of alloimmunized patients was 1.2:1.Transfusion interval in immunized patients was 5 to 20 days Mean SD;12 4.79 and in non-immunized patients interval was7 days to 5 weeks Mean SD; 20 10.2.


This study was conducted to find out the frequency of red cell alloantibodies and autoantibodies in thalassaemic children in our hospital so that the need for pretransfusion screening in these patients can be evaluated. The rates of immunization have been variably reported across the world. According to our study the frequency of development of red cell alloimmunization in thalassaemic patients receiving multiple blood transfusions in our set up is 8.5% and autoantibodies 2.3%. Our results are in agreement with studies conducted at Agha Khan University Karachi by Bilwani et al who revealed a rate of alloimmunization of 9.2% in 97 patients of thalassaemia major. Fifty three patients were males and 44 females. Mean age was 10.6 years. Mean age of patients who developed red cell alloimmunization was 11.9 years.Thompson reported on 697 thalassemic patients who had received transfusions. Alloand auto-antibodies were reported in 115 (16.5%) and 34 (4.9%) subjects respectively. Alloantibodies occurred in 19 of 91 (21%) splenectomized subjects who started transfusion after 1990 and only 18 of 233 (7.7%) nonsplenectomized subjects (P less than 0001). Data from this study demonstrate that RBC antibodies continue to develop in chronically transfused thalassaemia patients at a high rate. Splenectomy preceded the development of antibodies in most cases. Increased rates of RBC sensitization among splenectomized patients is concerning and deserves further study.8Pahuja et al in India studied the frequency of alloimmunization among 211 multitransfused thalassemics of Indian origin. All the patients have been receiving blood matched for ABO and Rh(D) antigens only. The frequency of alloimmunization was 3.79%. The alloantibodies identified were anti-E anti-K anti-D anti-Kp(a) anti-C(w) anti-c and anti-Jk(a). In the present study no significant association was observed between splenectomy and the development of alloantibodies as well as between ages at initiation of transfusion.14Gupta conducted a study on 116 thalassemics receiving regular transfusion. Red cell alloantibodies were found in 11 patient's i.e 9.48%. Mean age of the patients was 14 years (1.5 to 27 years).the interval between consecutive transfusions varied from 18 to 30 days. The common alloantibodies found were antiE and antiK. None of the 8 out of 116 patients who underwent splenectomy showed any antibody development.5Noor et al studied 58 multiply transfused thalassemia patients. Red cell alloantibodies were found in 5 of 58 patients (8.6%) Layla AM et al in Bahrain found out that out of 76 thalassemic patients nine (11.8%)had developed allimmunization.1516In our study most of the patients were between the ages of 6 10 years. Five patients had history of mild hemolytic transfusion reactions. Higher frequency of alloimmunization was observed in Rh negative patients. Two patients with autoantibodis presented with increased hemolysis and difficulty in cross matching. Least incompatible issued to them and immunosupression started. There is no doubt that alloimmunization is a significant clinical problem in multiple transfused patients and many strategies were suggested to reduce its development thereby avoiding such complication as the difficulty of obtaining compatible RBCs and also preventing the occurrence of delayed haemolytic transfusion reactions which usually occur in a small percentage of such patients. Controversy exists as to whether limited versus extended red cell phenotyping for ABO and D in addition to other minor blood types in transfusion-dependant patients should be done before the patients receive their first matched RBC transfusion. The weight of published evidence leans heavily on limited phenotyping (ABO D C E and Kell) other than being costly and time consuming extended phenotyping.17 Due to high cost a study from Brazil recommended the use of extended matched transfusions only to patients who have already developed one or more RBC alloantibodies.18 In our institute we are following a similar protocol; i.e. routine ABO and D typing for all transfusion dependant patients and reserving further phenotyping only when a patient becomes alloimmunized. In Pakistan antibody screening is not included with cross match before transfusion. Therefore we should weigh benefits against cost of doing antibody screening at the start of blood transfusion and it is recommended that pre-transfusion antibody screening on patients samples needs to be initiated in Pakistan to ensure safe transfusion practice so that antigen negative blood can be provided.It is concluded that red cell alloantibodies and autoantibodies should not be overlooked in patients with thalassemia major receiving regular blood transfusions. It should always be considered if the patient repeatedly suffers from haemolytic transfusion reaction or not being able to maintain haemoglobin at a desired level inspite of regular transfusions. Guidelines should be considered for local blood banks with limited technical facilities and donor resources and where phenotypically matched blood cannot always be made available.


The authors are thankful to their hospitals for providing the clinical material for this study.


1. Aessopos A Kati M Meletis J. Thalassemia Inter-mediatoday: should patients regularly receive transfusion. Transfusion 2007; 47: 792-800.2. Wang LY Liang DC Liu HC Alloimmunization among patients with transfusion dependent thalassemia in Taiwan. Transfus Med 2006; 16: 200-3.3. Ahmed S Saleem M Petrou M Screening Extended Families for Genetic Hemoglobin Disorders in Pakistan. N Engl J Med 2002; 347: 1162-1168.4. Singer ST Wu V Mignacca R. Alloimmunization and erythrocyte autoimmunization in transfusion dependent thalassemia patients of predominantly Asian descent. Blood 2000; 96 (10): 3369-73.5. Gupta R Goyal S et al. Red Cell Alloimmunization InRoutinely Transfused Patients of Beta Thalassemia Major; IJBTI 2010; 1 (1): 1-4.6. Salama MA Sadek NA Hassab HM Abadeer AF Mikhael IL. Erythrocyte autoantibodies and expression of CD59 on the surface of red blood cells of polytransfused patients with beta-thalassaemia major.Br J Biomed Sci.2004; 61: 8892.7. Ansari S Voosogh P Moshtaghian S. Assessment of frequency of alloimmunization and erythrocytes autoimmunization in transfusion dependent thalassemic patients. Acta Medica Iranica 2008; 46: 137-140.8. Thompson AA Cunningham MJ Singer ST Neufeld EJ et al. Red cell alloimmunization in a diverse population of transfused patients with thalassemia .British Journal of Haematology. April 2011; 153 (1): 121-128.9. Bilwani F Kakepoto GN Adil SN Frequency of irregular red cell alloantibodies in patients with thalassemia major: a bi-center study. J Pak Med Assoc 2005; 55: 563.10. Hassan K Younus M Ikram N Naseem L Zaheer HA.Red cell alloimmunization in repeatedly transfused Thalassemia Major. Int Pathol 2004; 2: 16-19.11. Bhatti FA Salamat N Nadeem A Shabbir N. Red Cell Immunization in Beta Thalassemia Major. J Coll Physician Surg Pak 2004; 14 (11): 657-60.12. Sadeghian MH Keramati MR Badiei Z Ravarian M et al. Alloimmunization among transfusion dependent thalassemia patient. Asian J Transfus Sci. 2009; 3 (2):9598.13. Chaudari CN Red cell alloantibodies in multiply transfused thalassemia Patients. Medical Journal Armed Forces India January 2011; vol. 67 No. 1.14. Pahuja S Pujani M Gupta SK Chandra J Jain M. Alloimmunization in multitransfused thalassemics of Indian origin. Hematology 2010 Jun: 15 (3): 174-7.15. Noor HMN Ariffin N Illuni H Roseline H. Red cell im-munization in multiply transfused Malay thalassemic patients. Southeast Asian J Trop Med Public Health2006; 37: 1015-20.16. Bashwari L Ahmed M EL-Fawaz N AL-Qatary A Ahmed MA. Red Cell Alloimmunization in Thalassemia Patients. Bahrain Med Bull 2005: 27 (2): 12-16.17. Gader AGMA et al. Transfusion medicine in a develop-ing country Alloantibodies Transf Apheres Sci 2008.18. Moreira Jr G Bordin JO Kuroda A Kerbauy J. Red blood cell alloimmunization in sickle cell disease: the influence of racial and antigenic pattern differences between donors and recipient in Brazil. Am J Hematol1996; 52: 197200.
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Date:Mar 31, 2014

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