G20210A Prothrombin gene mutation in two siblings with cerebral venous thrombosis

The G20210A mutation in the 3′-untranslated region of the prothrombin gene is a recently identified cause of thrombophilia that increases the risk of peripheral venous thrombosis.¹ We report two siblings with central venous thrombosis (CVT) heterozygous for this mutation. The pedigree analysis shows an autosomaldominant inherited pattern of venous thrombotic disease.

Case reports. The propositus (IV-8) was 19 years old when she was admitted for sudden onset of left hemiplegia. In April 1996, 6 days after tooth extraction, she developed intracranial hypertension within 24 hours, followed 2 days later by drowsiness, complete left motor deficit, and a bilateral Babinski sign. She smoked five cigarettes a day and used an oral contraceptive. The patient was afebrile. Results of general examination were normal and she had no local sign of dental or pharyngeal infection. A cerebral CT scan showed a right heterogeneous temporo-parietal hyperdensity with a mass effect consistent with a hemorrhagic transformation of parenchymal infarction. Cerebral angiography and MRI showed a thrombosis of the right transverse sinus. Laboratory investigations showed no inflammatory blood markers and results of immunologic tests were negative. Protein C, S, and antithrombin III plasma …