Sudden unexpected death in childhood (SUDC) : characteristics, autopsy findings and investigations

Sudden unexpected death in childhood (SUDC) can occur in previously apparently healthy children, and in those with known pre-existing and potentially life-limiting conditions. As a relatively rare event, SUDC remains largely un-investigated due to the small number of cases encountered by very few centres. Great Ormond Street Hospital performs specialist post-mortem examinations on behalf of Her Majesty's Coroner, including cases of SUDC, and has established a research database detailing the results from 1996 to date. In this study the findings from all unexpected deaths in children aged 1-16 years over a 20-year period from 1996-2015 have been investigated to determine the clinical characteristics, demographics and autopsy findings in SUDC. There were 548 sudden unexpected deaths from natural causes, 265 in previously apparently healthy children (SUDC) and 283 in children with pre-existing, potentially life-limiting conditions (SUDC-PEC). Infection was the commonest cause of death (43%), followed by unexplained deaths (29%) and non-infectious disease (28%). Detailed analysis of the SUDC cohort revealed that almost 25% had autopsy diagnoses with implications for other family members, future pregnancies or public health. Current hypotheses for unexplained SUDC were investigated including developmental abnormalities of the hippocampus, for which we found no correlation, however there were some limitations. Detailed examination of the post-mortem procedure revealed that some ancillary investigations were rarely performed. This may reflect a lack of standardised guidelines during the study period. Screening tests for inherited metabolic diseases were performed in <40% and it is possible that some IMDs have not been recognised. This study highlights the importance of specialist autopsy with ancillary investigations for accurate diagnosis in SUDC, in particular to identify those with potential implications for other family members and Public Health. The recent introduction of more standardised guidelines may help to reduce the current proportion of unexplained deaths.