Sudden death in an infant with central nervous system abnormalities.

Some deaths during the first year of life are classified as sudden infant death syndrome (SIDS), the diagnosis of which requires a complete autopsy without adequate explanation for the death. We report a 1-month-old infant whose clinical history was fairly typical for SIDS. Postmortem examination was remarkable in revealing clinically unsuspected central nervous system (CNS) abnormalities, including lobar holoprosencephaly, absence of the olfactory tracts and grooves (arhinencephaly), subependymal gray matter heterotopias, and delayed myelination. Although the CNS findings do not adequately explain the patient's sudden death, this case illustrates the need for a complete autopsy to include careful CNS evaluation, especially in any presumed SIDS death.