Correlation of gestational age and age at death in sudden infant death syndrome: another pointer to the role of critical developmental period?

BACKGROUND: Filiano and Kinney proposed a triple-risk model for the sudden infant death syndrome (SIDS) that involves the intersection of three risks: (1) a vulnerable infant, (2) a critical developmental period in homeostatic control, and (3) an exogenous stressor(s). The primary evidence for the role of a critical developmental period in SIDS etiology is the peak of cases around the third month of life. Independently, several studies pointed to correlation between gestational age and age at death in SIDS, but used that to assess the SIDS risk for preterm infants, ignoring further ramifications. METHODS: We did a detailed analysis of CDC data spanning over two decades (1983-2011). We focused not only on the correlation between two age variables (gestational and age at death), but also on the possibility of misdiagnosis. Also, we attempted to account for potential biases in the data induced by the ICD-9/ICD-190 transition or the "Back to Sleep" campaign. RESULTS: The peak of deaths in the third month of life, that was the main argument for the role of the critical development period, wasn't unique to SIDS. However, we confirmed an almost linear and negative correlation between gestational age and the week of death due to SIDS. This pattern (slope of correlation < 0 and significance of correlation p < 0.05) is characteristic of SIDS among all diseases analyzed in the study. CONCLUSIONS: We interpret the results as the evidence of the role of the critical development period in SIDS etiology. Possibly more attention in the future research should be put to theories that are based on homeostatic control.

Sudden Unexpected Postnatal Collapse: Review and Management.

Sudden unexpected postnatal collapse (SUPC) of healthy newborns is a catastrophic event caused by cardiorespiratory collapse in a healthy newborn. The most common cause of SUPC is poor positioning of the newborn during skin-to-skin contact or breastfeeding when the newborn is not being observed by a health professional, attentive parent, or caretaker. Maternal/newborn health care professionals need to know about the essential information, definitions, incidence, risk factors, clinical presentation, outcomes, and prevention and management strategies to minimize the occurrence and impact of SUPC. A sample SUPC hospital policy is included in the manuscript.

Practices and Awareness Regarding an Infant's Sleep Environment among Japanese Caregivers: A Cross-Sectional Survey.

Preventing sudden, unexpected infant death related to sleep, especially suffocation and sudden infant death syndrome, remains challenging globally. To evaluate factors associated with an unsafe sleep environment (SE) for infants in Japan, this cross-sectional study investigated the current status of practices and awareness among caregivers about a safe SE. Two hundred and fifty-four caregivers of infants in Yamaguchi Prefecture participated. Among the caregivers, 96.0% could not thoroughly practice a safe SE, although 65.0% had knowledge about a safe SE. More unsafe SE practices were significantly associated with 8- to 11-month-old infants than with 0- to 3-month-old infants, using the same practice as for an older child than with accessing information or a familiar person than with mass media as the most useful source of information. The differences in having knowledge were not associated with their practice. Many caregivers obtained information about an infant's SE from mass media and a familiar person. They preferred education via a face-to-face method by medical experts to raise awareness about a safe SE. Thus, efforts need to be developed in Japan in which experts who directly attend to caregivers can truly educate them to ensure that caregivers are continuously aware of the importance of an SE.

Sudden Infant Death Associated with Rhinovirus Infection.

A less than one-month-old infant with symptoms of rhinitis died unexpectedly in his sleep. He was not born prematurely and had no known underlying disease. Cerebrospinal fluid, nasopharyngeal and lung samples, and rectal swab were found to be positive for subgroup A rhinovirus, while the blood was negative. This case highlights the important finding that the rhinovirus, a common pathogen associated with upper respiratory tract infections, can sometimes, as the only pathogen, lead to complications such as a cerebrospinal infection and be involved in the sudden infant death syndrome (SIDS). Vigilance is necessary in case of viral infections in the infant's environment, and measures of hygiene and protection must be encouraged in order to reduce the risk of the SIDS.

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.

Sudden death with cardiac involvement in a neonate with carnitine-acylcarnitine translocase deficiency.

A female neonate born with normal Apgar scores at 38+2 weeks of gestational age unexpectedly passed away within less than 30 hours after birth. The situation mirrored her brother's earlier demise within 24 hours post-delivery, suggesting a possible genetic disorder. Gross examination revealed widespread cyanosis and distinct yellowish changes on the cardiac ventricles. Histopathological examination disclosed lipid accumulation in the liver, heart, and kidneys. Tandem mass spectrometry detected elevated levels of 10 amino acids and 14 carnitines in cardiac blood. Trio-whole genome sequencing (Trio-WGS) identified the SLC25A20 c.199-10T>G mutation associated with carnitine-acylcarnitine translocase disease (CACTD), a type of fatty acid oxidation disorders (FAODs) with a potential for sudden death. Further validation of gene expression confirmed the functional deficiency of SLC25A20, ultimately diagnosing CACTD as the underlying cause of the neonate's demise. This case highlights the importance of prenatal metabolic and genetic screening for prospective parents and emphasizes the need for forensic doctors to integrate metabolomic and genomic investigations into autopsies for suspected inherited metabolic diseases.

The Tension Between AAP Safe Sleep Guidelines and Infant Sleep.

OBJECTIVES: To understand tension mothers experience when attempting to follow American Academy of Pediatrics safe sleep guidelines and enhancing infant and parental sleep. METHODS: Surveys and focus groups were conducted from November 2022 and March 2023 with United States-based English-speaking mothers of infants <6 months of age recruited via social media and who reported a nonrecommended sleep position and/or location ≥2 times the prior week. RESULTS: Twenty-five mothers participated in focus groups and surveys. A total of 80% reported holding or rocking their infant to sleep; 76% fed their infant to sleep. Almost all were aware of the ABCs (Alone, Back, Crib) of safe sleep and intended to follow them before delivery. Many felt that ABCs were unrealistic and placed their infants in nonrecommended locations or positions because they perceived them as more comfortable and helping their infant fall and stay asleep. Mothers were more likely to use nonrecommended practices when they were awake or sleeping nearby and believed they could closely monitor their infant. Some questioned whether ABCs were the only way to achieve safe sleep. Some prioritized other safety concerns (eg, fall prevention) over sudden infant death syndrome or sudden unexpected infant death prevention. Mothers expressed confidence about getting their baby to sleep in general but were less confident that they could do this while following guidelines. CONCLUSIONS: Despite awareness of the ABCs, mothers regularly engaged in nonrecommended practices with the goal of improving their own and their infant's sleep. Interventions focused on improving infant and parental sleep while maintaining sleep safety are needed.

A Rare Case of Neonatal Hypomagnesemia with Secondary Hypocalcemia Caused by a Novel Homozygous TRPM6 Gene Variant.

BACKGROUND Familial hypomagnesemia with secondary hypocalcemia (HSH) is a rare autosomal recessive disorder (OMIM# 602014) caused by mutations in the gene encoding transient receptor potential melastatin 6 (TRPM6)) on chromosome 9q22, a channel involved in epithelial magnesium resorption. While a plethora of studies have delineated various clinical manifestations pertinent to this mutation, the literature is devoid of connections between TRPM6 mutations and bleeding diathesis, or sudden infant death syndrome (SIDS). This report presents a case of familial HSH associated with the novel homozygous TRPM6 gene variant c.5281C>G p. (Arg1761Gly) chr9: 77354845. CASE REPORT This report details a 26-day-old neonate, born full term with optimal Apgar scores, who experienced an abrupt emergence of apnea, cyanosis, bilateral nasal bleeding, and diminished alertness. Despite the neonate's initially unremarkable clinical birth indicators, a meticulous assessment unveiled a pronounced family history of SIDS, including a sibling previously diagnosed with hypomagnesemia. Laboratory examination of the infant demonstrated severe hypomagnesemia and hypocalcemia, conditions which were promptly ameliorated following intravenous administration of magnesium and calcium. Whole-exome sequencing identified a homozygous TRPM6 gene mutation c.5281C>G p. (Arg1761Gly) at chr9: 77354845. This gene is crucial for magnesium regulation. The mutation involves a cytosine-to-guanine shift, resulting in an arginine to glycine amino acid substitution at position 1761 of the TRPM6 protein. CONCLUSIONS This report has highlighted that infantile hypomagnesemia may be associated with symptoms and signs that can mimic infection, or it can present with seizures. Although familial HSH is a rare genetic disorder that can be identified by genetic testing, correction of hypomagnesemia is the most important and immediate clinical management strategy.

Community infant safe sleep and breastfeeding promotion and population level-outcomes: A mixed methods study.

PROBLEM: In the U.S., sudden unexpected infant deaths due to accidental suffocation and strangulation in bed are increasing. Though breastfeeding is a protective factor against sudden unexpected infant death, motivations to breastfeed often couple with unsafe infant sleep practices. Racial/ethnic disparities are present in sudden unexpected infant death, accidental suffocation and strangulation in bed, and breastfeeding. BACKGROUND: Promoting infant safe sleep and breastfeeding through community-level initiatives could address disparities in related outcomes. AIM: Investigate the relationship between community-level strategies and associated state-level outcomes for infant safe sleep and breastfeeding. METHODS: We employed an intervention mixed methods framework and exploratory sequential design. The qualitative component entailed a hermeneutical phenomenological framework to analyze key informant interview data from seven U.S. community-level providers participating in a practice improvement initiative. The quantitative component entailed descriptively analyzing infant safe sleep and breastfeeding indicators from the 2019 Pregnancy Risk Assessment Monitoring System and Ohio Pregnancy Assessment Survey. Qualitative and quantitative data were linked through embedded integration. FINDINGS: We identified two mixed insights: gaps in promotion and outcomes, and persistent disparities between infant safe sleep and breastfeeding promotion and outcomes. DISCUSSION: Our findings indicate conversational approaches could improve infant safe sleep and breastfeeding promotion, outcomes, and relative disparities. We find that community collaboration is needed to address organizational capacity limitations in promoting infant safe sleep and breastfeeding. CONCLUSION: Community-level organizations and providers should consider tailoring program offerings and care delivery to include conversational approaches and community collaboration to promote infant safe sleep and breastfeeding and decrease relative disparities in outcomes.

The Relation of Maternal Psychosocial Risk Factors to Infant Safe Sleep Practices.

OBJECTIVES: Sleep-related infant deaths are a common and preventable cause of infant mortality in the United States. Moreover, infants of color are at a greater risk of sleep-related deaths than are White infants. The American Academy of Pediatrics (AAP) published safe sleep guidelines to minimize the number of sleep-related infant deaths; however, many families face barriers to following these guidelines. Research on the role of psychosocial risk factors (i.e., depression, stress, domestic violence, substance use) in mothers' engagement in safe sleep practices is limited. The present study examined the role of maternal psychosocial risk factors on maternal safe sleep practices and the moderating effects of maternal race on this relationship. METHODS: Participants in this study were mothers (N = 274) who were recruited from a Midwestern hospital postpartum. Data on the participants' psychosocial risk factors, and safe sleep practices were collected via telephone interview 2-4 months following the birth of their infant. RESULTS: Predictive models indicated that depression and stress impacted mothers' engagement in following the safe sleep guidelines. Specifically, higher levels of maternal depression predicted greater likelihood of co-sleeping, regardless of mothers' race. Higher levels of maternal stress also predicted lower engagement in safe sleep behaviors for White mothers only. CONCLUSION FOR PRACTICE: Early interventions to address stress and depression may help to increase maternal adherence to the AAP's safe sleep guidelines. Additional research on the underlying mechanisms of depression and stress on maternal safe sleep engagement is needed.

Identifying infants at risk of sudden unexpected death with an automated predictive risk model.

BACKGROUND/OBJECTIVE: Sudden unexpected infant death (SUID) is a common cause of infant death. We evaluated whether a predictive risk model (PRM) - Hello Baby - which was developed to stratify children by risk of entry into foster care could also identify infants at highest risk of SUID and non-fatal unsafe sleep events. PARTICIPANTS AND SETTING: Cases: Infants with SUID or an unsafe sleep event over 5½ years in a single county. CONTROLS: All births in the same county. METHODS: Retrospective case-control study. Demographic and clinical data were collected and a Hello Baby PRM score was assigned. Descriptive statistics and the predictive value of a PRM score of 20 were calculated. RESULTS: Infants with SUID (n = 62) or an unsafe sleep event (n = 37) (cases) were compared with 23,366 births (controls). Cases and controls were similar for all demographic and clinical data except that infants with unsafe sleep events were older. Median PRM score for cases was higher than controls (17.5 vs. 10, p < 0.001); 50 % of cases had a PRM score 17-20 vs. 16 % of controls (p < 0.001). CONCLUSIONS: The Hello Baby PRM can identify newborns at high risk of SUID and non-fatal unsafe sleep events. The ability to identify high-risk newborns prior to a negative outcome allows for individualized evaluation of high-risk families for modifiable risk factors which are potentially amenable to intervention. This approach is limited by the fact that not all counties can calculate a PRM or similar score automatically.

Risk factors for unexpected infant death among very premature infants in France.

BACKGROUND: Prematurity is one of the risk factors for sudden unexpected infant death (SUID), a phenomenon that remains poorly explained. MATERIALS AND METHODS: The analysis of specific factors associated with SUID among very premature infants (VPI) was performed through a retrospective review of data collected in the French SUID registry from May 2015 to December 2018. The factors associated with SUID among VPI were compared with those observed among full-term infants (FTI). Results are expressed as means (standard deviation [SD]) or medians (interquartile range [IQR)]. RESULTS: During the study period, 719 cases of SUID were included in the registry, 36 (incidence: 0.60 ‰) of which involved VPI (gestational age: 29.2 [2] weeks, 1157 [364]) g] and 313 (0.18 ‰) involved FTI (gestational age: 40 [0.8] weeks, 3298 [452] g). The infants' postnatal age at the time of death was similar in the two groups: 15.5 (12.2-21.8) vs. 14.5 (7.1-23.4) weeks. We observed low breastfeeding rates and a high proportion of fathers with no occupation or unemployment status among the VPI compared to the FTI group (31% vs. 55 %, p = 0.01 and 32% vs. 13 %, p = 0.05, respectively). Among the VPI, only 52 % were in supine position, and 29 % were lying prone at the time of the SUID (compared to 63 % and 17 %, respectively, in the FTI group). CONCLUSION: This study confirms prematurity as a risk factor for SUID with no difference in the SUID-specific risk factors studied except for breastfeeding and socioeconomic status of the fathers. VPI and FTI died at similar chronological ages with a high proportion of infants dying in prone position. These results argue for reinforcement of prevention strategies in cases of prematurity.

Estudio poblacional forense de la muerte súbita inexplicada en la epilepsia en niños y jóvenes durante el periodo 1991-2021 / Forensic population study of sudden unexplained death in epilepsy in children and young people during the period 1991–2021

Introducción la muerte súbita inexplicada en la epilepsia (MSIEP) es una causa importante de mortalidad en los pacientes epilépticos jóvenes; sin embargo, su existencia es poco conocida en el ámbito forense. El objetivo del trabajo es analizar la frecuencia y características clínico-patológicas de la MSIEP en los epilépticos menores de 35 años. Métodos estudio observacional de todas MSIEP ocurridas en personas de 1-35 años en Bizkaia (periodo 1991-2021) y Sevilla (2004-2021) investigadas en los servicios de patología forense (SPF). Además, se examinaron las muertes por epilepsia de los registros de mortalidad. Resultados se registraron 101 muertes por epilepsia en los registros de mortalidad y 46 MSIEP en los SPF, representando el 6% de las muertes súbitas en esta edad. Se registró una alta frecuencia de casos de epilepsia postraumática (n = 5), o con anomalías cerebrales (n = 5) o asociadas a trastornos del desarrollo (n = 4) o retraso mental (n = 3). El estudio toxicológico fue positivo en el 75%, destacando la presencia de fármacos antiepilépticos (n = 26). Se detectaron drogas ilegales en 5 jóvenes, principalmente cocaína (n = 3). La muerte fue no presenciada en la mayoría de los sujetos (85%) y sucedió por la noche (n = 63%) durante el sueño. Conclusiones la MSIEP en los niños y los jóvenes es infrecuente, pero constituye una causa importante de mortalidad en los epilépticos. Aunque los mecanismos de la MSIEP no son bien conocidos, se recomienda reforzar el control médico de la epilepsia en la juventud, principalmente en los pacientes con epilepsia postraumática o posquirúrgica o en aquellos con trastornos del desarrollo o retraso mental asociados. (AU)

Introduction Sudden unexpected death in epilepsy (SUDEP) is a major cause of mortality in young epileptic patients. The objective of the work is to analyze its frequency and clinical-pathological characteristics as a cause of sudden death in epileptics under 35 years of age. Methods Retrospective population study of all SUDEP in people aged 1–35 years in Bizkaia (period 1991–2021) and Seville (2004–2021) investigated in the Forensic Pathology Services (FPS). In each case, a complete autopsy was carried out with histopathological and toxicological studies, and review of clinical and circumstantial data. Data from the Mortality Registry for deaths by epilepsy were examined. Results 101 deaths due to epilepsy were registered in the Mortality Registries and 46 SUDEP cases in the FPS, representing 6% of forensic sudden deaths in this age population. A high frequency of post-traumatic epilepsy cases (n = 5), brain abnormalities (n = 5) or epilepsy associated to developmental disorders (n = 4) or mental retardation (n = 3) was observed. The toxicological analysis was positive in 75%, highlighting the presence of antiepileptic drugs (n = 26). Illegal drugs were detected in 5 young people, mainly cocaine (n = 3). Death was unwitnessed in most subjects (85%) and occurred at night (n = 63%) while sleeping. Conclusions SUDEP in children and young people is infrequent, however it is an important cause of mortality in epileptics. Although the mechanisms are not well understood, it is recommended to strengthen the medical control of epilepsy in youth, mainly in patients with post-traumatic or post-surgical epilepsy or in those who have associated developmental disorders or mental retardation. (AU)

Characteristics of Sudden Unexpected Infant Deaths on Shared and Nonshared Sleep Surfaces.

OBJECTIVES: Describe characteristics of sudden unexpected infant deaths (SUID) occurring on shared or nonshared sleep surfaces. METHODS: We examined SUID among residents of 23 US jurisdictions who died during 2011 to 2020. We calculated frequencies and percentages of demographic, sleep environment, and other characteristics by sleep surface sharing status and reported differences of at least 5% between surface sharing and nonsharing infants. RESULTS: Of 7595 SUID cases, 59.5% were sleep surface sharing when they died. Compared with nonsharing infants, sharing infants were more often aged 0 to 3 months, non-Hispanic Black, publicly insured, found supine, found in an adult bed or chair/couch, had a higher number of unsafe sleep factors present, were exposed to maternal cigarette smoking prenatally, were supervised by a parent at the time of death, or had a supervisor who was impaired by drugs or alcohol at the time of death. At least 76% of all SUID had multiple unsafe sleep factors present. Among surface-sharing SUID, most were sharing with adults only (68.2%), in an adult bed (75.9%), and with 1 other person (51.6%). Surface sharing was more common among multiples than singletons. CONCLUSIONS: Among SUID, surface sharing and nonsharing infants varied by age at death, race and ethnicity, insurance type, presence of unsafe sleep factors, prenatal smoke exposure, and supervisor impairment. Most SUID, regardless of sleep location, had multiple unsafe sleep factors present, demonstrating the need for comprehensive safe sleep counseling for every family at every encounter.

Altered 5-HT2A/C receptor binding in the medulla oblongata in the sudden infant death syndrome (SIDS): Part II. Age-associated alterations in serotonin receptor binding profiles within medullary nuclei supporting cardiorespiratory homeostasis.

The failure of chemoreflexes, arousal, and/or autoresuscitation to asphyxia may underlie some sudden infant death syndrome (SIDS) cases. In Part I, we showed that some SIDS infants had altered 5-hydroxytryptamine (5-HT)2A/C receptor binding in medullary nuclei supporting chemoreflexes, arousal, and autoresuscitation. Here, using the same dataset, we tested the hypotheses that the prevalence of low 5-HT1A and/or 5-HT2A/C receptor binding (defined as levels below the 95% confidence interval of controls-a new approach), and the percentages of nuclei affected are greater in SIDS versus controls, and that the distribution of low binding varied with age of death. The prevalence and percentage of nuclei with low 5-HT1A and 5-HT2A/C binding in SIDS were twice that of controls. The percentage of nuclei with low 5-HT2A/C binding was greater in older SIDS infants. In >80% of older SIDS infants, low 5-HT2A/C binding characterized the hypoglossal nucleus, vagal dorsal nucleus, nucleus of solitary tract, and nuclei of the olivocerebellar subnetwork (important for blood pressure regulation). Together, our findings from SIDS infants and from animal models of serotonergic dysfunction suggest that some SIDS cases represent a serotonopathy. We present new hypotheses, yet to be tested, about how defects within serotonergic subnetworks may lead to SIDS.

Infant death from accidental suffocation and strangulation in bed in England and Wales: rare or unrecognised events?

BACKGROUND: Mandatory joint police and healthcare investigations of sudden unexpected death in infancy (SUDI) have been in place since 2008 in England. These include death scene examination with cause of death determined at multiprofessional case conference. Detailed evidence on sleep arrangements is available for most cases potentially leading to more being identified as due to accidental suffocation. SUDI remaining unexplained following investigation are classified as SIDS (sudden infant death syndrome) or unspecified deaths.Our objective was to determine whether detailed SUDI investigation has led to an increase in deaths classified as accidental suffocation or strangulation in bed (ASSB)? METHODS: We obtained official mortality data for England and Wales for infants dying aged 0-364 days for International Statistical Classification of Diseases and Related Health Problems, 10th revision codes R95 (SIDS), R96, R98, R99 (unspecified causes of mortality) and W75 (ASSB) for the years 2000-2019.We calculated the mortality rate for ASSB, SIDS and unspecified causes based on total live births each year. RESULTS: Unexplained SUDI decreased from 353 in 2000 to 175 in 2019, with the mortality rate falling from 0.58 to 0.29 per 1000 live births. The total postneonatal mortality rate fell during this time from 1.9 to 0.9 per 1000 live births suggesting this is a genuine fall. SIDS accounted for 70% of unexplained SUDI in 2000 falling to 49% in 2020 with a corresponding increase in R99 unspecified deaths.Few deaths were recorded as ASSB (W75), ranging between 4 in 2010 and 24 in 2001. The rate for ASSB ranged from 0.6 to 4.0 per 100000 live births. CONCLUSIONS: There is a shift away from SIDS (R95) towards unspecified causes of death (R96, R98, R99). Improved investigation of deaths has not led to increased numbers of death identified as due to ASSB. There needs to be clear guidelines on accurate classification of deaths from ASSB to facilitate learning from deaths and inform prevention efforts.

Multiomic Analysis of Neuroinflammation and Occult Infection in Sudden Infant Death Syndrome.

Importance: Antemortem infection is a risk factor for sudden infant death syndrome (SIDS)-the leading postneonatal cause of infant mortality in the developed world. Manifestations of infection and inflammation are not always apparent in clinical settings or by standard autopsy; thus, enhanced resolution approaches are needed. Objective: To ascertain whether a subset of SIDS cases is associated with neuroinflammation and occult infection. Design, Setting, and Participants: In this case-control study, postmortem fluids from SIDS cases and controls collected between July 2011 and November 2018 were screened for elevated inflammatory markers, specifically cerebrospinal fluid (CSF) neopterin and CSF and serum cytokines. CSF, liver, and brain tissue from SIDS cases with elevated CSF neopterin were subjected to metagenomic next-generation sequencing (mNGS) to probe for infectious pathogens. Brainstem tissue from a subset of these cases was analyzed by single-nucleus RNA sequencing (snRNAseq) to measure cell type-specific gene expression associated with neuroinflammation and infection. All tissue and fluid analyses were performed from April 2019 to January 2023 in a pathology research laboratory. Included was autopsy material from infants dying of SIDS and age-matched controls dying of known causes. Exposures: There were no interventions or exposures. Main Outcomes and Measures: CSF neopterin levels were measured by high-performance liquid chromatography. Cytokines were measured by multiplex fluorometric assay. mNGS was performed on liver, CSF, brain, and brainstem tissue. snRNAseq was performed on brainstem tissue. Results: A cohort of 71 SIDS cases (mean [SD] age, 55.2 [11.4] postconceptional weeks; 42 male [59.2%]) and 20 controls (mean [SD] age, 63.2 [16.9] postconceptional weeks; 11 male [55.0%]) had CSF and/or serum available. CSF neopterin was screened in 64 SIDS cases and 15 controls, with no exclusions. Tissues from 6 SIDS cases were further analyzed. For CSF neopterin measures, SIDS samples were from infants with mean (SD) age of 54.5 (11.3) postconceptional weeks (38 male [59.4%]) and control samples were from infants with mean (SD) age of 61.5 (17.4) postconceptional weeks (7 male [46.7%]). A total of 6 SIDS cases (9.3%) with high CSF neopterin were identified, suggestive of neuroinflammation. mNGS detected human parechovirus 3 (HPeV3) in tissue and CSF from 1 of these 6 cases. snRNAseq of HPeV3-positive brainstem tissue (medulla) revealed dramatic enrichment of transcripts for genes with predominately inflammatory functions compared with 3 age-matched SIDS cases with normal CSF neopterin levels. Conclusions and Relevance: Next-generation molecular tools in autopsy tissue provide novel insight into pathogens that go unrecognized by normal autopsy methodology, including in infants dying suddenly and unexpectedly.

Knowledge about sudden infant death syndrome prevention among postpartum women in Southern Brazil, 2019: a cross-sectional survey.

OBJECTIVE: To assess knowledge on sudden infant death syndrome (SIDS) prevention among postpartum women who received prenatal care in public and private services in Rio Grande, Rio Grande do Sul, Brazil, in 2019. METHODS: A cross-sectional study was conducted with postpartum women who gave birth in that municipality in 2019; the outcome was the indication of incorrect sleeping position (side/supine position) to prevent SIDS; the chi-square test was used to compare proportions between those who underwent prenatal care in public and private services. RESULTS: Among all 2,195 postpartum women, 67.7% (95%CI 65.7;69.6) were unaware of the position that prevents SIDS, 71.6% were public care service users; 77.8% of them feared choking/suffocation; 1.9% were informed about SIDS during prenatal care; doctors/nurses (70.5%) and grandmothers (65.1%) were influential regarding the baby's sleeping position. CONCLUSION: Most postpartum women were unaware of the sleeping position that prevents SIDS, especially those receiving care in the public sector; in general, this subject is not discussed in prenatal care. MAIN RESULTS: Two out of three mothers believed the newborn should sleep in the side or prone position, which does not prevent but rather facilitates sudden infant death syndrome (SIDS); lack of knowledge was significantly greater when prenatal care took place in public services. IMPLICATIONS FOR SERVICES: SIDS should be addressed in prenatal care. Guidance from a doctor/nurse during consultations can be essential for mothers to change their mind and adopt a safe sleeping position (supine position) for their child. PERSPECTIVES: SIDS prevention campaigns are relevant in the context of prenatal care, as is conducting research that aims to evaluate potential impacts of interventions on the correct sleeping position for babies.