Related Experiment Videos
Screening coagulation tests and clotting factors in homozygous beta-thalassemia
Insights
Children with beta-thalassemia show minor hemostasis changes, but decreased clotting factors IX and XII. Thrombocytosis is noted in splenectomized patients, suggesting complex coagulation system alterations.
Area of Science:
- Hematology
- Pediatric Medicine
- Coagulation Disorders
Background:
- Homozygous beta-thalassemia is a severe inherited blood disorder.
- Patients often require frequent blood transfusions, impacting various physiological systems.
- Hemostasis and coagulation factor levels in pediatric thalassemia patients are not fully elucidated.
Purpose of the Study:
- To evaluate hemostasis screening tests, platelet counts, and specific clotting factor levels in children with homozygous beta-thalassemia.
- To investigate potential correlations between transfusion history and coagulation status.
- To explore the underlying mechanisms of coagulation abnormalities in this patient population.
Main Methods:
- Hemostasis screening tests (bleeding time, PT, PTT) were performed.
- Platelet counts and specific clotting factor assays were conducted.
- Data were collected 25 days post-transfusion in 30 children with homozygous beta-thalassemia.
Main Results:
- Minor variations observed in bleeding time, PT, and PTT.
- Significant thrombocytosis noted in splenectomized patients.
- Decreased levels of Factor IX and Factor XII found in a high proportion of patients; vitamin K-dependent factors (II, VII, IX, X) were slightly reduced.
Conclusions:
- Coagulation factor deficiencies, particularly Factors IX and XII, are common in children with beta-thalassemia.
- Hepatic dysfunction does not fully explain the observed factor impairments.
- Intravascular hemolysis and multiple transfusions may activate intrinsic coagulation and kallikrein systems, contributing to factor abnormalities.
Abstract:
In 30 children with homozygous beta-thalassemia the hemostasis screening tests (bleeding time, PT, PTT), platelet count and specific assays of clotting factors were carried out 25 days after their last transfusion. PT, PTT, and bleeding time showed minor variations; considerable thrombocytosis was found in splenectomized patients. Factors IX and XII were decreased in a high proportion of patients, the vitamin K-dependent factors (II, VII, IX, X) were slightly reduced and factors I, V and VIII remained within the normal range in a majority of patients. Hepatic failure resulting in defective protein synthesis does not explain the more marked impairment of factors XI and XII, which might be secondary to activation of the intrinsic coagulation and/or kallikrein systems following intravascular haemolysis and multiple blood transfusions.