Hippocampal abnormalities and sudden childhood death.

Abstract

The papers by Hefti et al. [1, 2] confirm and expand upon the group’s prior report of hippocampal abnormalities found in young children with sudden unexpected death. In the present studies, the investigators take advantage of the pathologic dataset made available through the San Diego Sudden Unexplained Death in Childhood (SUDC) research project. Eighty percent of the cases were classified as SUDC with smaller numbers associated with an explained cause, undetermined, or related to a seizure. Unexpectedly, there was a significant percentage of SUDC individuals with a history of febrile seizures or a family history of febrile seizures (nearly 50 %), and in 50 % of the cases of SUDC the hippocampal formation was found to be histologically abnormal. The authors emphasize the association of SUDC, a history of febrile seizures, and developmental abnormalities of the hippocampus including dentate granule microarchitecture abnormalities and hippocampal rotational abnormalities, and use the term hippocampal maldevelopment associated with sudden death (HMASD) to characterize the lesion. The association of a history of febrile seizures and SUCD was previously reported [3] but not clearly associated with any specific pathology. When the hippocampus was studied more closely, a relationship between pathologic abnormalities and SUCD was suggested [4, 5]. The current studies provide further evidence of a potential relationship between febrile seizures or familial tendency to febrile seizures, SUDC, and underlying hippocampal abnormalities. These observations raise some interesting, and potentially important questions.