Abstract □ 78

Prevention has 2 levels: individual and population. In all countries the number of sudden infant deaths (SIDS) has dramatically decreased these past years due to the « preventing the risks » campaigns including back sleeping. But nobody can tell currently which infants in particular are more at risk for dying. Postmortem (PM) investigations are essential for both making diagnoses and directing research. PM data are related to - cause of death - death mechanism - contributing factors - incidental data - resuscitation manoeuvres - agonic phenomenons - PM changes. The main difficulty is of course the suddeness of the death. It makes necessary the cooperation of pediatrician(s), biologist, microbiologist and pathologist(s) through an extensive PM protocol and for interpreting the results. This multidisciplinary approach allows recording of all the cases' findings for building a SIDS epidemiology based upon positive findings. In a series of 40 consecutive SIDS aged from 1 month to 1 year who had extensive PM investigations, we had: - position: 31/39 infants were found prone (79.5%); - clinical symptoms prior to death: 14/40 (35%) were doing well, 11/40 (27.5%) had a rhinitis including coughing in 3, and 15/40 (37.5%) had 1 (11 cases), 2 (3 cases) or 3 (1 case) alarm symptoms: fever (7 cases), drowsyness (4 cases), anorexia (3 cases), important crying and fidgeting (3 cases), vomiting and diarrhea (2 cases), ALTE (1 case), usual snoring (1 case); identified pathologies after clinico-pathological correlations (according to the main findings): - 34/40 (85%) positive microbiology - 13 gastric content aspirations (with a positive microbiology in 11) - 10 diffuse bacterial and/or viral infections - 7 gastroenteritis including 1 severe acute dehydration - 7 urinary infections - 7 septicaemias - 5 enteroviral infections - 2 meningitis - 2 respiratory infections (RSV) - 2 severe pulmonary edema - 1 cardiac pathology (rhabdomyomas); histological shock signs: found in 22/39 (56.4%) cases including a positive microbiology in 20/22 (90.9%) cases. Thus infection seems to be an important factor. It is found in 36/40 (90%) of our SIDS cases. The difficulty is to know which role that infection played in the death of this specific child. Indeed, infection is very common at that age, and most infants can deal with it. Identification of actors that endanger an individual have to be pursued: high bacterial toxicity, poor host resistance, unadequate inflammatory answer, underlining condition such as prematurity sequellae, dysmaturity or immaturity, small upper airways, obstructive sleep apneas, mild facial dysmorphies. Individual prevention could be considered also if the child has clinical symptoms. There should be a specific parents' and pediatricians' education for a better evaluation of clinical status. In case of alarm symptoms and even in case of what seems to be a minor illness, it could be useful to systematically - make a clinical examination with weighing and growth curve - detect a sub-clinical hypoxaemia, an arrhythmia especially during viral infection (enterovirus, RSV), and to search for a bacterial infection: CSF, blood and urine cultures. Most of all, « back to sleep » campaigns shall be continued and intensified. Monitoring is not a prevention but only a way of dealing with the parents' stress. In conclusion, these data suggest that some more SIDS could be preventable.