Seroepidemiological study of alloimmunization and antinuclear antibody in Sudanese patients with homozygous sickle cell disease receiving frequent transfusion therapy.

Abstract

Abstract Transfusion of red blood cells is a major therapeutic option for anemia in homozygous sickle cell disease (SCD), it is limited by the development of alloantibodies to erythrocytes. On the other hand, the coexistence of SCD and autoimmune diseases which is characterized by the production of antibodies to the nuclear materials lead to increased suffering of the patients since they share numbers of clinical features which may lead to delay or miss diagnosis of the underline disease. Since description of the first case of SCD in Sudan at I926, there was and still increasing research activities in this field. Unfoitunately, no studies published in open literature to determine the frequency and alloimmunization and the coexistence of autoimmune diseases in SCD, as far as we know. The objectives ofthis study were to determine the frequency of alloimmunization in frequent transfusion and the frequencies of anti nuclear antibodies (ANA) and the anti double stranded DNA (anti- dsDNA) in SCD patients receiving frequent transfusion therapy in Sudan. This study was conducted at Albuluk Pediatric Teaching Hospital and Omdurman Pediatric Hospital between August 20ll and April 2012. Questionnaires were used to collect demographic and clinical data include sex, age. tribe, number and indication for transfusion, transfusion reaction, and malarial attack . Blood samples were collected from hundred (n=l00) SCD (HbSS) patients of age between 6 month - l7 years, both males (57%) and females (43%) who had received at least 2 transfusions with units of ABO and D matched RBCs. lmmunohematological and immunological investigations were done on patient samples, and the frequencies of alloimmunization , ANA and anti-dsDNA were determined. The mean number ofblood‘s units transfused per patient was 6.73 (SD,4.46l). The patients were transfused with a total of 673 (maximum, 20; minimum,2) units of blood. Fifty five percent ofthe patients had been transfused from non relative donors, while 45% from relative donors. (4%) ofthe patients were developed alloantibodies, all antibodies belong to the Rhesus and Kell system. The alloimmunization appears to be affected by the number of transfusion episodes (P= 0.002), and not affected by patients sex (P= 0.578). Blood group O appears to be predominant on other ABO blood group antigens (46%), and the percentage of Rhesus antigens: D+, d, C, c, E and e in the total sample was 96%, 4%, 33%, 67%, 13% and 100%, respectively.

ANA was found in (17.3%) of patients compared to (0.7%) of control group (P= 0.0l3), the females showed dominance in positivity, (3.l%) of the patients were positive to anti-dsDNA. None of the control were positive for antibodies to dsDNA. The females are at four times higher risk for developing of ANA than males (Odd Ratio = 3.871 (Cl 95% l.244 — 12.048), P=0.0l5)