Serum levels of antiphospholipid antibodies among patients with sickle cell anaemia in Zaira Nigeria

Abstract

Background: Antiphospholipid (APL) antibody is rarely reported in patients with sickle cell anaemia (SCA). It is an autoimmune response to phospholipid in which negatively charged phospholipids translocate from the inner to the outer surface of red blood cell (RBC) membranes, leading to the potential generation of an antigenic target in patients SCA following recurrent Vaso-occlusive episodes. Subsequent induction of APL antibody is characterized by recurrent fetal loss, arterial or venous thrombosis and thrombocytopenia with a mortality rate of 50%, due to multi-organ dysfunction. This study aimed to determine the prevalence of both Anticardiolipin (aCL) and β2 glycoprotein 1(β2GP1) IgM and IgG antibodies among adult patients with SCA in Ahmadu Bello University Teaching Hospital Zaria (ABUTH), Nigeria. Methods: A comparative cross-sectional study of patients with SCA (HbSS) as Study group and prospective blood donors (HbAA) as control, of ages 18years and above. Ethical approval was obtained and a total of 118 participants were enrolled after an informed consent; 79 HbSS and 39 HbAA. Haematological parameters were determined by multiparameter analyzer Swelab alfa while Serum levels of Anti cardiolipin (aCL) antibody and β2 glycoprotein 1 (β2GPI) IgM/IgG were evaluated using ELISA technique, Sunlong Biotec LTD (SL12654Hu). Data was analyzed using SPSS version 23 and level of significance was set at p ≤ 0.05. Results: Out of the total number of SCA subjects studied 59.5% (47/79) were females while males constitute 89.7% (35/39) of the control. The median age of the study group (HbSS) and controls (HbAA) were 22 and 28 years respectively. The median haemoglobin concentration of the SCA subjects 7.70g/dl (1.90) was significantly lower than that of the control group 13.80g/dl (1.70), p <0.0001. The Median (IQR) of aCL IgG/M and β2GP1 IgG/M of the study group were; 48(16.00)u/ml, 22(9.00)u/ml and 548(100.00)ug/L, 113(88.00)ug/L respectively and were significantly higher when compared with that of the control group aCL IgG/M and β2GP1 IgG/M; 41(5.00)U/ml, 16(6,00)U/ml and 521(42.00)ug/L, 54(48.00)ug/L) respectively (p<0.0001). The prevalence of aCL antibodies was 2.5% IgG and 5.1% IgM while 5.3% IgG and 3.8% IgM for ß2-GP1. Conclusion: The elevated levels of APL antibody in patients with SCA may serve as a tool for the monitoring and surveillance of disease severity and thus a treatment and prognostic index for the improvement of the quality of care of these patients.