Release of erythroblasts to the peripheral blood suggests higher exposure to hypoxia in cases of SIDS with co-sleeping compared to SIDS non-co-sleeping

The diminishing role of the pathologist in sudden infant death syndrome

All major definitions of sudden infant death syndrome (SIDS) specify that a careful pathological examination must be conducted which includes performance of a "complete" autopsy. Unfortunately, there is an increasing trend for cases to be classified as SIDS without fulfilling the required criteria, even including cases where an autopsy has not been performed. Failure to have an experienced pathologist with an understanding of SIDS involved in every step of the investigation and follow-up, with or without subsequent studies, may severely undermine the veracity of the diagnosis and the reliability of subsequent research conclusions.

Inflammatory, regulatory, and autophagy co-expression modules and hub genes underlie the peripheral immune response to human intracerebral hemorrhage

BACKGROUND

Intracerebral hemorrhage (ICH) has a high morbidity and mortality. The peripheral immune system and cross-talk between peripheral blood and brain have been implicated in the ICH immune response. Thus, we delineated the gene networks associated with human ICH in the peripheral blood transcriptome. We also compared the differentially expressed genes in blood following ICH to a prior human study of perihematomal brain tissue.

METHODS

We performed peripheral blood whole-transcriptome analysis of ICH and matched vascular risk factor control subjects (n = 66). Gene co-expression network analysis identified groups of co-expressed genes (modules) associated with ICH and their most interconnected genes (hubs). Mixed-effects regression identified differentially expressed genes in ICH compared to controls.

RESULTS

Of seven ICH-associated modules, six were enriched with cell-specific genes: one neutrophil module, one neutrophil plus monocyte module, one T cell module, one Natural Killer cell module, and two erythroblast modules. The neutrophil/monocyte modules were enriched in inflammatory/immune pathways; the T cell module in T cell receptor signaling genes; and the Natural Killer cell module in genes regulating alternative splicing, epigenetic, and post-translational modifications. One erythroblast module was enriched in autophagy pathways implicated in experimental ICH, and NRF2 signaling implicated in hematoma clearance. Many hub genes or module members, such as IARS, mTOR, S1PR1, LCK, FYN, SKAP1, ITK, AMBRA1, NLRC4, IL6R, IL17RA, GAB2, MXD1, PIK3CD, NUMB, MAPK14, DDX24, EVL, TDP1, ATG3, WDFY3, GSK3B, STAT3, STX3, CSF3R, PIP4K2A, ANXA3, DGAT2, LRP10, FLOT2, ANK1, CR1, SLC4A1, and DYSF, have been implicated in neuroinflammation, cell death, transcriptional regulation, and some as experimental ICH therapeutic targets. Gene-level analysis revealed 1225 genes (FDR p < 0.05, fold-change > |1.2|) have altered expression in ICH in peripheral blood. There was significant overlap of the 1225 genes with dysregulated genes in human perihematomal brain tissue (p = 7 × 10-3). Overlapping genes were enriched for neutrophil-specific genes (p = 6.4 × 10-08) involved in interleukin, neuroinflammation, apoptosis, and PPAR signaling.

CONCLUSIONS

This study delineates key processes underlying ICH pathophysiology, complements experimental ICH findings, and the hub genes significantly expand the list of novel ICH therapeutic targets. The overlap between blood and brain gene responses underscores the importance of examining blood-brain interactions in human ICH.

WITHDRAWN: Abnormal Muscularization of Intra Acinar Pulmonary Arteries in 2 Cases Presenting as Sudden Infant Death (SIDS)

This article was accidentally published Online First and in Volume 20 Issue 1 with different DOI. There was no duplication of the article in the printed version of Volume 20 Issue 1. The incorrect version of the article with DOI: 10.1177/1093526617698597 has been replaced with this correction notice. The correct and citable version of the article remains: Zainun K, Hope K, Nicholson AG, Cohen MC. Abnormal muscularization of intra-acinar pulmonary arteries in two cases presenting as sudden infant death. PDP. 2017;20(1):49-53. doi: 10.1177/1093526616689311.

Infant pacifiers for reduction in risk of sudden infant death syndrome

BACKGROUND

Sudden infant death syndrome (SIDS) has been most recently defined as the sudden unexpected death of an infant less than one year of age, with onset of the fatal episode apparently occurring during sleep, that remains unexplained after a thorough investigation, including the performance of a complete autopsy and a review of the circumstances of death and clinical history. Despite the success of several prevention campaigns, SIDS remains a leading cause of infant mortality. In 1994, a 'triple risk model' for SIDS was proposed that described SIDS as an event that results from the intersection of three factors: a vulnerable infant; a critical development period in homeostatic control (age related); and an exogenous stressor. The association between pacifier (dummy) use and reduced incidence of SIDS has been shown in epidemiological studies since the early 1990s. Pacifier use, given its low cost, might be a cost-effective intervention for SIDS prevention if it is confirmed effective in randomised controlled trials.

OBJECTIVES

To determine whether the use of pacifiers during sleep versus no pacifier during sleep reduces the risk of SIDS.

SEARCH METHODS

We used the standard search strategy of the Cochrane Neonatal Review Group to search the Cochrane Central Register of Controlled Trials (CENTRAL 2016, Issue 2), MEDLINE via PubMed, Embase, and CINAHL to 16 March 2016. We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

Published and unpublished controlled trials using random and quasi-random allocations of infants born at term and at preterm (less than 37 weeks' gestation) or with low birth weight (< 2500 g). Infants must have been randomised by one month' postmenstrual age. We planned to include studies reported only by abstracts, and cluster and cross-over randomised trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed studies from searches. We found no eligible studies.

MAIN RESULTS

We identified no randomised controlled trials examining infant pacifiers for reduction in risk of SIDS.

AUTHORS' CONCLUSIONS

We found no randomised control trial evidence on which to support or refute the use of pacifiers for the prevention of SIDS.

Abnormal Muscularization of Intra-acinar Pulmonary Arteries in Two Cases Presenting as Sudden Infant Death

Abnormal muscularization of acinar arteries is the hallmark of persistent pulmonary hypertension of newborn (PPHN), an uncommon disease with high rate of morbidity and mortality. PPHN presents with signs of respiratory distress immediately following birth. We herein report 2 cases presenting as a witnessed sudden unexpected death in the late neonatal period, preceded by respiratory deterioration and in whom the presence of abnormal muscularization of the acinar pulmonary arteries was reminiscent of PPHN. The significance of this report is twofold: to increase the awareness among pediatricians and pathologists of this feature that can present in some cases of Sudden Unexpected Death in Infancy/Sudden Infant Death Syndrome, and to highlight the importance of performing a thorough autopsy in order to identify the abnormality.

Parent-child bed-sharing: The good, the bad, and the burden of evidence

The practice of parent and child sharing a sleeping surface, or 'bed-sharing', is one of the most controversial topics in parenting research. The lay literature has popularized and polarized this debate, offering on one hand claims of dangers, and on the other, of benefits - both physical and psychological - associated with bed-sharing. To address the scientific evidence behind such claims, we systematically reviewed 659 published papers (peer-reviewed, editorial pieces, and commentaries) on the topic of parent-child bed-sharing. Our review offers a narrative walkthrough of the many subdomains of bed-sharing research, including its many correlates (e.g., socioeconomic and cultural factors) and purported risks or outcomes (e.g., sudden infant death syndrome, sleep problems). We found general design limitations and a lack of convincing evidence in the literature, which preclude making strong generalizations. A heat-map based on 98 eligible studies aids the reader to visualize world-wide prevalence in bed-sharing and highlights the need for further research in societies where bed-sharing is the norm. We urge for multiple subfields - anthropology, psychology/psychiatry, and pediatrics - to come together with the aim of understanding infant sleep and how nightly proximity to the parents influences children's social, emotional, and physical development.

Developmental nicotine exposure enhances inhibitory synaptic transmission in motor neurons and interneurons critical for normal breathing

Nicotine exposure in utero negatively affects neuronal growth, differentiation, and synaptogenesis. We used rhythmic brainstems slices and immunohistochemistry to determine how developmental nicotine exposure (DNE) alters inhibitory neurotransmission in two regions essential to normal breathing, the hypoglossal motor nucleus (XIIn), and preBötzinger complex (preBötC). We microinjected glycine or muscimol (GABAA agonist) into the XIIn or preBötC of rhythmic brainstem slices from neonatal rats while recording from XII nerve roots to obtain XII motoneuron population activity. Injection of glycine or muscimol into the XIIn reduced XII nerve burst amplitude, while injection into the preBötC altered nerve burst frequency. These responses were exaggerated in preparations from DNE animals. Quantitative immunohistochemistry revealed a significantly higher GABAA receptor density on XII motoneurons from DNE pups. There were no differences in GABAA receptor density in the preBötC, and there were no differences in glycine receptor expression in either region. Nicotine, in the absence of other chemicals in tobacco smoke, alters normal development of brainstem circuits that are critical for normal breathing.

Measurement of nucleated red blood cells in the peripheral blood as a marker of hypoxia in sudden unexpected death in infancy

AIMS

A recently proposed classification of sudden unexpected infant death incorporates consideration of possibly asphyxia. This depends on an adequate postmortem, scene investigation and history. A reliable marker of asphyxia has yet to be identified. Such a marker could assist in classifying these deaths. Our aim was to determine if the level of nucleated red blood cells (nRBCs) in the peripheral blood could help identify those possibly asphyxia-related deaths and if risk factors could influence this level in the peripheral blood.

METHODS

Cases of sudden unexpected deaths in infancy and sudden infant death syndrome (SIDS) which occurred over a period of 6 years (2007-2013) and were autopsied at Sheffield Children's Hospital were reviewed and categorised according to a new classification proposed by Randall et al. The cases were then correlated with the blood level of nRBCs determined at the time of post mortem examination. The study was approved by the Clinical Governance Department, number SE331.

RESULTS

139 deaths were classified into Group A (true SIDS, 67 cases), Group B (possible asphyxia related, 24 cases), Group C (non-asphyxia-related, 6 cases), Group D (no crime scene investigation, 0 cases) and Group E (identifiable cause, 42 cases). The levels were significantly increased in ex-premature babies, in infants with an underlying condition (Group C) and in deaths related to illness or trauma (Group E). There was a trend towards higher levels of nRBCs in younger age groups and in babies born to smoking mothers.

CONCLUSIONS

SIDS remains a difficult diagnosis to make despite the current medical technological advances where no marker of hypoxia has yet been identified.

Increased number of fetal nucleated red blood cells in the placentas of term or near-term stillborn and neonates correlates with the presence of diffuse intradural hemorrhage in the perinatal period

Release of nucleated red blood cells (nRBCs) into the peripheral blood occurs in stillbirths/neonates with a probable hypoxic mode of death and antenatal stress. We correlated the number of nRBCs in the placenta with the occurrence of intradural (IDH) and subdural hemorrhage (SDH) and the potential link with fetal hypoxia. Two groups of 22 cases each of nonmacerated term or near-term (≥36 weeks of gestational age) stillborn or newborns dying in the 1st day of life were studied. One group had IDH (with or without SDH) and the other did not have IDH or SDH. In each case, the number of nRBCs was determined in 10 consecutive placental fields at ×40. Data were analyzed with Fisher exact test, receiver operating characteristic (ROC) curve analysis, and logistic regression. There was a significant association between the diffuse IDH and increased number of nRBCs (Fisher exact test P  =  0.0165). An ROC curve analysis showed that the cut-off number of nRBCs with the highest accuracy was 2.15 nRBCs/high-power field, with 79% sensitivity and 67% specificity. The presence of diffuse IDH was associated with SDH (Fisher exact test, P  =  0.002). The absence of hypoxic brain change was associated with the absence of diffuse IDH (odds ratio 0.308; P  =  0.039). We established a significant correlation between the release of nRBCs into the placental circulation and the occurrence of diffuse IDH and between diffuse IDH and the presence of SDH.