[Factor V Leiden mutation as a cause of venous thrombosis]

Venous thrombosis is infrequent in paediatrics. A lot of prothrombotic risk factors have been described. Disturbances of coagulation are present in more than half of children with stroke. Leiden V factor mutation is emphasized as one of the most common genetic cause of deep venous thrombosis in Caucasian children and adults, which represents 20-25%, depending on series.

Two years-old girl with hypoxic-ischemic disease and West syndrome, which presents a deep venous thrombosis in both legs. This evolved to gangrene, requiring surgical exceresis of scar and amputation of 2nd, 3rd and 4th fingers of left foot. She also presented a right frontoparietal intraparenchima haemorrhagic stroke with tetraventricular bleeding and hydrocephalus. It required an external ventricular derivation and later a Ventricular-peritoneal valve.

The coagulation study confirmed the Leiden V factor mutation in our patient. Later studies showed the same mutation in the father. The risk of recurrence and the severity of venous thrombosis indicate life antiaggregant treatment, currently maintained with aspirin.