Naturally Occurring Anticoagulants and Their Association With Thromboembolism In Patients With β-Thalassemia Major

Hypercoagulopathy and thromboembolic manifestations are being increasing acknowledged in transfusion dependent thalassemics; both intermedia and major. Studies in preceding decade have shown that hemostatic alterations including natural anticoagulant deficiency obligate thalassemic for thromboembolism. The aim of our study is to determine the status of natural anticoagulants and their association with thromboembolism during follow up.

This is a prospective case-control study, during which 40 cases and 30 controls were registered between Jan 2009 to Dec 2009. Complete blood count, protein C, protein S, antithrombin, serum ferritin, liver function test; HbsAg and Anti HCV were determined. Patients were followed till 30^th June 2012 for thromboembolic disease.

Data was entered and analyzed using SPSS version 17. The results were expressed as mean ± SD for quantitative variables and qualitative variables are presented as frequency & percentages. Student‘t’ test was applied for the comparison of means. We also computed spearman correlation at 5% level of significance to identify relationship between the deficiency of natural anticoagulants with maternal characteristics, hematological parameters and biochemical markers. Chi- square test was applied for correlation of prothrombotic markers with hepatitis B & C.

The mean age of patients and control was 12.30±5.5 and 13.39±4.5 years respectively. There were 21 males and 19 females in patient group. The mean protein C, protein S and antithrombin in patients and control were 58.25±22.5 versus 110.67±22.60 (P<0.001), 67.90±19.58 versus 98.70±21.54 and 89.73±18.09 versus 104.0±10.98 (P<0.001) respectively. Protein C was exceedingly deficient in 65% followed by protein S & antithrombin in 35% and 20% respectively. Protein S deficiency revealed positive correlation with protein C deficiency and hemoglobin ≤ 8 gm% was correlated with antithrombin deficiency(P<0.05). No positive correlation of prothrombotic markers were established with others parameters evaluated. Till June 2012, 7 patients were lost to follow up and 2 died owing to cardiac failure. Of the 31 patients in regular follow up none has experienced thromboembolism both clinically and radiologically.

Decremented prothrombotic markers, primarily protein C, are implicated in elevated thrombotic risk in TM patients. However we did not encounter thromboembolism in our patients during follow up. We recommend prothrombotic screening and prophylactic anticoagulation in high risk group: bed bound splenectomized, cardiopulmonary complications and post operative.

No relevant conflicts of interest to declare.