1996; Siegel et al. 2005). In our cohort, one-third of index patients that were shown to carry a heterozygous mutation in either CCM1,CCM2 or CCM3 are children or adolescents. Since fulminant courses of the disease have only rarely been reported in infants affected with CCM (Ng et al. 2006; Sürüçü et al. 2006; Gianfrancesco et al. 2007), we describe two CCM1 mutation carriers who presented with hemiparesis during their second and third year of life requiring immediate surgical intervention. Here, KRIT1 is linked to cerebral cavernous malformation.