Late onset of clinical symptoms and recurrent ecchymotic skin lesions in a 12-year-old girl with a severe double heterozygous protein C deficiency.

The authors describe a 12-year-old girl with late-onset clinical symptoms due to severe protein C deficiency. Protein C gene analysis showed double heterozygosity for two distinct mutations, associated with type I protein C deficiency. Her parents and only brother were also evaluated. Coumarin-induced skin necrosis was a recurrent feature during oral anticoagulation therapy, forcing her physicians to treat her with nadroparin (Fraxiparin) for only a few months.