CNS lesions in neonatal isoimmune thrombocytopenia.

We treated two siblings with classic neonatal isoimmune thrombocytopenia and porencephalic cysts in whom the CNS lesions occurred in a vascular distribution, for which there is no clear explanation. Whether the CNS vasculature is injured by the immune process at certain susceptible sites in larger vessels or whether there is a thrombotic process occurring at sites of vascular injury is speculative. This observation suggests that vascular factors are involved in the development of CNS lesions in this condition.