Blood coagulation changes in homocystinuria: effects of pyridoxine and other specific therapy

Area of Science:

• Hematology
• Biochemistry
• Metabolic Disorders

Background:

• Homocystinuria is an inherited metabolic disorder characterized by elevated homocysteine levels.
• Increased thrombotic risk is a known complication of homocystinuria, but the underlying hemostatic mechanisms are not fully understood.

Observation:

• Baseline assessment revealed reduced antithrombin III activity and factor VII levels in all three patients.
• Additional baseline abnormalities included decreased antithrombin III protein and protein C antigen in one patient, and reduced factor X in another.
• Elevated beta-thromboglobulin indicated platelet activation in one patient.

Findings:

• Pyridoxine treatment rapidly normalized antithrombin III activity.
• Factor VII levels increased, and beta-thromboglobulin decreased following pyridoxine therapy.
• These findings suggest that antithrombin III deficiency contributes to the thrombotic tendency in homocystinuria.

Implications:

• The study highlights the role of blood coagulation abnormalities, particularly antithrombin III reduction, in homocystinuria-associated thrombosis.
• Improvement of clotting factors during metabolic treatment suggests a direct impact of the amino acid transsulfuration defect on liver-dependent clotting factors.
• These insights may guide therapeutic strategies targeting hemostasis in homocystinuria patients.