Around two thirds of sudden unexpected deaths in infancy (SUDI) remain unexplained following post-mortem examination. It has been postulated that a subset of unexplained SUDI may be caused by toxigenic Staphylococcus aureus. The aim of this study was to compare the prevalence of toxigenic S aureus strains in unexplained and explained SUDI (those in whom a cause of death is determined at autopsy). A retrospective review was performed of 546 SUDI autopsies as part of a larger review of >1,500 pediatric autopsies over a 10-year period, 1996-2005 inclusive. SUDI was defined as the sudden and unexpected death of an infant aged 7-365 days, and categorized into unexplained, explained with histological evidence of infection (bacterial infection group) or explained due to non-infective causes. Toxin gene profiling was carried out by PCR in cases in whom S aureus was isolated as part of clinical investigation. Of the 507 SUDI included in this analysis, bacteriological investigations were performed in 470, and S aureus was isolated on post-mortem culture from at least one site in 173 (37%). There were significantly more cases with S aureus isolated in unexplained SUDI (40%) compared to non-infective SUDI (21%; difference 19.0%, 95% CI 5.4% to 29.3%, P = 0.006). 46% of all cases with S aureus isolated underwent routine testing for a panel of staphylococcal toxin genes (including SEA to SEE, SEG to SEJ, TSST-1, and exfoliative toxins A and B). There were more cases with at least one toxigenic strain of S aureus in the unexplained SUDI (81%) and bacterial infection groups (77%) than in the non-infection group (63%), but these differences were not statistically significant (Fisher exact test, P = 0.44). Toxin gene-carrying S aureus is commonly detected at autopsy in SUDI, accounting for 78% of S aureus isolates submitted for toxin gene profiling in this series. There is a significantly higher prevalence of S aureus in unexplained SUDI compared to non-infective SUDI, but no significant difference in the proportion with toxigenic S aureus strains isolated between the groups. These data are consistent with the hypothesis that a subset of otherwise unexplained SUDI may be related to the presence of S aureus colonization/infection, but do not indicate routine testing for toxin-associated genotypes.

INTRODUCTION:Myocarditis is a recognised cause of cardiac failure in childhood but the frequency of myocarditis as a cause of sudden unexpected death across the paediatric age range is uncertain. METHODS:A structured review of the results of all autopsies carried out in a single paediatric centre over a 10-year period, including the results of all investigations performed as part of the centre's policy for the post-mortem investigation of paediatric deaths. RESULTS:During the study period there were 1516 autopsies of children aged 0-18 years. Histologically proven myocarditis was present in 28 cases (1.8%, age range 10 days to 16 years, median age 10 months), of which 16 (57%) presented as sudden death. More than half of all cases (54%) occurred in infants less than 1 year of age, accounting for 2% of infant deaths referred for autopsy, compared with around 5% of childhood deaths over the age of 5 years. In almost 40% of cases there were no macroscopic cardiac abnormalities, the diagnosis being entirely dependent on routine histological examination of the heart, and post-mortem heart weight was normal in the majority of cases. Virus was detected in nine (36%) of the 25 cases in whom virological analyses were performed. The histological features were similar in all cases, with an interstitial inflammatory cell infiltrate, predominantly lymphocytic, with focal myocyte necrosis and interstitial oedema. CONCLUSIONS:Myocarditis is a rare cause of death in infancy and childhood, and the majority of cases present as sudden unexpected deaths, which require routine histological sampling of the heart for its detection.

We present a male infant with antenatally detected, focal, unilateral apparently isolated renal cystic disease with morphological features of renal involvement in tuberous sclerosis. Only one previous case with similar presentation has been described. Most affected children present with either diffuse bilateral renal cystic disease or extrarenal manifestations. The major genes involved in tuberous sclerosis are now well described, and early onset of severe renal cystic disease in affected children often is related to the presence of a contiguous gene deletion syndrome involving TSC2 and PKD1 on chromosome 16.

We present an unusual case of post-transplant lymphoproliferative disorder (PTLD) presenting as apparently isolated gastrointestinal lesions in a pediatric renal transplant recipient. The multiple bowel lesions were related to Epstein-Barr virus and demonstrated the appearance of a monomorphic PTLD that was morphologically indistinguishable from diffuse large B-cell lymphoma. The patient responded to therapy with targeted anti-CD20 immunotherapy. PTLD may manifest as apparently isolated gastrointestinal tract lesions in childhood.