LUPUS ANTICOAGULANT IN NIGERIAN CHILDREN WITH HOMOZYGOUS SICKLE CELL DISEASE

Background: Lupus anticoagulant (LA) is an antiphospholipid antibody (APLA), which recognise combinations of phospholipids or phospholipid -binding proteins or both and interfere with coagulation reactions dependent on protein phospholipid complexes in vitro. LA has paradoxically been associated with thrombosis and a myriad of clinical conditions such as cerebrovascular accidents (CVA). APLA have been described in adult homozygous sickle cell disease (SCD) patients and adults with β- thalassaemia. Our objective was to determine the presence or otherwise of LA in children with homozygous SCD and to see if they were more prone to developing LA compared to normal HbAA controls. Method: A total of 57 children with homozygous SCD between the ages 1-15 years were prospectively screened for the presence of LA using the kaolin clotting time (KCT), while 52 healthy HbAA children served as controls. KCT was performed in duplicates on all 109 subjects. Kaolin clotting time ratio was calculated to determine the presence of LA. A ratio greater than or equal to 1.2 was taken to signify the presence of LA. Results: One (1.8%) child with homozygous SCD had prolonged KCT, and this was not corrected by normal plasma, the KCT ratio was greater than 1.2, signifying the presence of LA. None of the control subjects had LA (p 0.05). Conclusion: One (1.8%) child in this study had LA; this value was not statistically significant when compared with HbAA controls. In spite of the fact that secondary LA is more common in females, the only patient with LA in our study was male and had no prior history of CVA or thrombosis.