Sudden infants death syndrome (SIDS) : Standardised investigations and classification: Recommendations

The anatomo-pathological research has been particularly focused to study the cardiac conduction and neuropathological substrates of SIDS and sudden unexplained perinatal death. The pathogenic mechanism leading to death is, in many cases, related to the triggering role of the autonomic reflexes caused by alterations, mostly of a congenital nature, of the autonomic nervous system which regulates vital activities of respiratory, cardiovascular, digestive and arousal type. It is thus essential that victims of infant perinatal death “sine causa” be subjected to an in-depth histopathologic examination focusing particularly on the cardiac conduction and on the autonomic nervous systems regulating the cardiac, respiratory, upper digestive and arousal activities. Cases of SIDS «gray zone» have been reported in which only our further investigations on serial sections successfully identified anatomo-pathological findings likely representing the morphological substrates for sudden death. Such borderline or «gray zone» SIDS cases have been described as those cases in which anatomo-pathological findings alone might not have accounted for the sudden deaths, if it had not been for the location and/or concomitant presence of brainstem abnormalities which could have had a triggering role in causing the infant sudden death.