Revisiting the Neuropathology of Sudden Infant Death Syndrome (SIDS)

New Step in Understanding the Pathogenetic Mechanism of Sudden Infant Death Syndrome: Involvement of the Pontine Reticular Gigantocellular Nucleus

This study aimed to investigate, for the first time, the potential role of the gigantocellular nucleus, a component of the reticular formation, in the pathogenetic mechanism of Sudden Infant Death Syndrome (SIDS), an event frequently ascribed to failure to arouse from sleep. This research was motivated by previous experimental studies demonstrating the gigantocellular nucleus involvement in regulating the sleep-wake cycle. We analyzed the brains of 48 infants who died suddenly within the first 7 months of life, including 28 SIDS cases and 20 controls. All brains underwent a thorough histological and immunohistochemical examination, focusing specifically on the gigantocellular nucleus. This examination aimed to characterize its developmental cytoarchitecture and tyrosine hydroxylase expression, with particular attention to potential associations with SIDS risk factors. In 68% of SIDS cases, but never in controls, we observed hypoplasia of the pontine portion of the gigantocellular nucleus. Alterations in the catecholaminergic system were present in 61% of SIDS cases but only in 10% of controls. A strong correlation was observed between these findings and maternal smoking in SIDS cases when compared with controls. In conclusion we believe that this study sheds new light on the pathogenetic processes underlying SIDS, particularly in cases associated with maternal smoking during pregnancy.

Sudden Infant Death Syndrome (SIDS): State of the Art and Future Directions

Sudden infant death syndrome (SIDS) is a type of death that occurs suddenly and without any apparent explanation, affecting infants between 28 days of life and up to a year. Recognition of this entity includes performing an autopsy to determine if there is another explanation for the event and performing both an external and internal examination of the different tissues to search for possible histopathological findings. Despite the relative success of awareness campaigns and the implementation of prevention measures, SIDS still represents one of the leading causes of death among infants worldwide. In addition, although the development of different techniques has made it possible to make significant progress in the characterization of the etiopathogenic mechanisms underlying SIDS, there are still many unknowns to be resolved in this regard and the integrative consideration of this syndrome represents an enormous challenge to face both from a point of view scientific and medical view as humanitarian. For all these reasons, this paper aims to summarize the most relevant current knowledge of SIDS, exploring from the base the characterization and recognition of this condition, its forensic findings, its risk factors, and the main prevention measures to be implemented. Likewise, an attempt will be made to analyze the causes and pathological mechanisms associated with SIDS, as well as potential approaches and future paths that must be followed to reduce the impact of this condition.

Machine Learning Model Based on Lipidomic Profile Information to Predict Sudden Infant Death Syndrome

Sudden infant death syndrome (SIDS) represents the leading cause of death in under one year of age in developing countries. Even in our century, its etiology is not clear, and there is no biomarker that is discriminative enough to predict the risk of suffering from it. Therefore, in this work, taking a public dataset on the lipidomic profile of babies who died from this syndrome compared to a control group, a univariate analysis was performed using the Mann–Whitney U test, with the aim of identifying the characteristics that enable discriminating between both groups. Those characteristics with a p-value less than or equal to 0.05 were taken; once these characteristics were obtained, classification models were implemented (random forests (RF), logistic regression (LR), support vector machine (SVM) and naive Bayes (NB)). We used seventy percent of the data for model training, subjecting it to a cross-validation (k = 5) and later submitting to validation in a blind test with 30% of the remaining data, which allows simulating the scenario in real life—that is, with an unknown population for the model. The model with the best performance was RF, since in the blind test, it obtained an AUC of 0.9, specificity of 1, and sensitivity of 0.8. The proposed model provides the basis for the construction of a SIDS risk prediction computer tool, which will contribute to prevention, and proposes lines of research to deal with this pathology.

Sudden infant death syndrome: Melatonin, serotonin, and CD34 factor as possible diagnostic markers and prophylactic targets

Sudden infant death syndrome (SIDS) is one of the primary causes of death of infants in the first year of life. According to the WHO's data, the global infant mortality rate is 0.64-2 per 1,000 live-born children. Molecular and cellular aspects of SIDS development have not been identified so far. The purpose of this paper is to verify and analyze the expression of melatonin 1 and 2 receptors, serotonin (as a melatonin precursor), and CD34 molecules (as hematopoietic and endothelial markers of cardiovascular damage) in the medulla, heart, and aorta in infants who died from SIDS. An immunohistochemical method was used to investigate samples of medulla, heart, and aorta tissues of infants 3 to 9 months of age who died from SIDS. The control group included children who died from accidents. It has been shown that the expression of melatonin receptors as well as serotonin and CD34 angiogenesis markers in tissues of the medulla, heart, and aorta of infants who died from SIDS is statistically lower as compared with their expression in the same tissues in children who died from accidents. The obtained data help to clarify in detail the role of melatonin and such signaling molecules as serotonin and CD34 in SIDS pathogenesis, which can open new prospects for devising novel methods for predictive diagnosis of development and targeted prophylaxis of SIDS.