SIDS Risk Factors: Time for New Interpretations. The Role of Bacteria

2015

Front. Immunol.

The gut microbiome influences the development of the immune system of young mammals; the establishment of a normal gut microbiome is thought to be important for the health of the infant during its early development. As the role of bacteria in the causation of sudden infant death syndrome (SIDS) is backed by strong evidence, the balance between host immunity and potential bacterial pathogens is likely to be pivotal. Bacterial colonization of the infant colon is influenced by age, mode of delivery, diet, environment, and antibiotic exposure. The gut microbiome influences several systems including gut integrity and development of the immune system; therefore, gut microflora could be important in protection against bacteria and/or their toxins identified in SIDS infants. The aims of the review are to explore (1) the role of the gut microbiome in relation to the developmentally critical period in which most SIDS cases occur; (2) the mechanisms by which the gut microbiome might induce inflammation resulting in transit of bacteria from the lumen into the bloodstream; and (3) assessment of the clinical, physiological, pathological, and microbiological evidence for bacteremia leading to the final events in SIDS pathogenesis.

Section: Evidence Of Infection In Sidsmentioning

confidence: 92%

Section: Evidence Of Infection In Sidsmentioning

confidence: 99%

Gut Microbiota and Immunity: Possible Role in Sudden Infant Death Syndrome

2015

Front. Immunol.

“…While our previous publications ( 1 , 16 , 26 ) proposed a plausible mechanism to account for the key risk factor of prone sleep position and which incorporated the idea of ingestion or inhalation of bacteria that contaminate the sleeping surface, supported by evidence showing such bacterially contaminated sleeping surfaces (parental bed, sofas, and previously used cot mattress) are proven risk factors for SIDS ( 27 – 30 ), there is a need to seek out additional and congruent physiological explanations to expand our knowledge and further explain the prone sleep risk factor. One of these might be the role of the vagus nerve, in particular in relation to interaction with the immune system and the gut microbiota.…”

Section: The Prone Sleep Position Risk Factor Neuroimmunology and Tmentioning

confidence: 93%

Sudden Infant Death Syndrome, Infection, Prone Sleep Position, and Vagal Neuroimmunology

2017

Front. Pediatr.

Recent findings suggest that infection (and sepsis) stand alone as the only plausible mechanism of causation of sudden infant death syndrome (SIDS) and accordingly achieves congruence with all clinicopathological and epidemiological findings. This review examines the role of infection in the pathogenesis of SIDS in the context of the major risk factor of prone sleep position. The study explores how sleep position could interact with the immune system and inflammatory response via vagal neural connections, which could play key roles in gut and immune homeostasis. A plausible and congruent clinicopathological and epidemiological paradigm is suggested.

“…Plausible explanations (e.g. the influence of prone position on the nasopharyngeal flora in promoting colonisation with toxigenic bacteria [8] , ingestion or inhalation of infective agents from the sleeping surface) have been proposed [42] . Published evidence that babies are at increased risk of SIDS if they sleep on a sofa [43] or sleep on a used (second-hand) mattress [44] , [45] or in a parental bed [46] seem to support this idea given the common finding of Staphylococcus aureus and Escherichia coli being associated with SIDS [47] .…”

Section: Evaluation Of the Hypothesismentioning

confidence: 99%

SIDS, prone sleep position and infection: An overlooked epidemiological link in current SIDS research? Key evidence for the “Infection Hypothesis”

2020

Medical Hypotheses

Mainstream researchers explain the etiology of SIDS with the cardiorespiratory paradigm. This has been the focus of intense study for many decades without providing consistent supporting data to link CNS findings to epidemiological risk factors or to the usual clinicopathological findings. Despite this, and the apparent oversight of the link between prone sleep position and respiratory infection, papers citing CNS, cardiac and sleep arousal findings continue to be published. Discovery of the prone sleep position risk factor provided tangential support for the cardiorespiratory control hypothesis which defines the mainstream approach. Despite many decades of research and huge expenditure, no aetiological answer has been forthcoming. In asking why?This paper exposes some of the shortcomings regarding this apparent oversight by mainstream SIDS researchers and examines the role of respiratory infection and puts the case for the “Infection Hypothesis.” In addition, the paper provides encouragement to neuropathologists to examine the potential link between CNS findings and cardiac function (as opposed to respiratory function) in relation to infection and to examine possible correlates between CNS findings and established risk factors such as recent infection, contaminated sleeping surfaces, maternal/obstetric/higher birth, ethnicity, non-breast-feeding, male gender, etc. or with the usual gross pathological findings of SIDS (intrathoracic petechial hemorrhages, liquid blood, congested lungs). The shortcomings exposed through this review invite questions over current research directions and hopefully encourage research into other more plausible hypotheses, such as the infection paradigm. Mainstream SIDS researchers appear to have overlooked the key relationship between prone sleep position and infection. This omission has major implications for current and future SIDS research.