Thrombotic risk of children with thalassemia.

Pulmonary microthromboembolism is one of the serious complications found in patients with thalassemia. The pathogenesis is undetermined. The thrombotic risk in 44 patients (26 males, 18 females) with beta-thalassemia/hemoglobin E disease and without clinical symptoms of thrombosis were studied. The age ranged from 3-19 yr (X +/- SD = 10 +/- 4). Neither of them had chronic hepatitis B infection. They were divided into three groups according to clinical manifestations as follows: (1) Mild form (n = 12). They did not require blood transfusion. The mean +/- SD of hematocrit was 23.3 per cent +/- 2.3; (2) Severe form (n = 19). They required frequent blood transfusion. The mean +/- SD of hematocrit was 17.7 per cent +/- 1.5; (3) Severe form with splenectomy (n = 13). They seldom required blood transfusion. The mean +/- SD of hematocrit was 21.8 per cent +/- 3.5. Most of the patients had delayed growth. They had high serum ferritin reflecting iron overload status which was prominent in the severe groups (group 2 & 3). The prothrombin time and serum albumin were slightly decreased, and the serum alanine transaminase were slightly increased; all of which reflected mild alteration of liver function. The plasma AT III, PC and PS antigen in the three groups were similar. The mean +/- SD of AT III antigen was 106.7 per cent +/- 22.2 which is normal. The mean +/- SD of PC antigen was 44.2 per cent +/- 14.2 and PS antigen level was 77.2 per cent +/- 17.8.(ABSTRACT TRUNCATED AT 250 WORDS)