An evaluation of pathologists' application of the diagnostic criteria from the San Diego definition of SIDS and unclassified sudden infant death.

Despite being widely used, few studies have assessed the utility of the San Diego definition of sudden infant death syndrome (SIDS). The purpose of this study was to evaluate pathologists' application of the San Diego definition in all cases of sudden unexpected death in infancy (SUDI) that occurred in Queensland, Australia, between 2010 and 2014. Key coronial documents of 228 cases of SUDI were reviewed independently by three reviewers and classified according to the San Diego definition. Clear guidance regarding the evidentiary threshold for classification and interpretation of the San Diego definition was provided. All reviewers classified cases identically in 202 cases (88.6%). Consensus was achieved on the classification of the remaining 26 deaths following case discussion. After review, 79 cases were classified as SIDS, a one third reduction compared with the original classification, mainly due to a high probability of accidental asphyxia. The number of cases classified as undetermined (USID) almost doubled (75/228, 32.9%), and there was more than a fivefold increase in cases classified as asphyxia (43/228, 18.9%). Natural conditions decreased by approximately one third (21/228, 9.2%). This study demonstrates that with clear guidelines for interpretation, the San Diego definition can be applied reliably, with discrepancies resolved through a process of peer review.

Inconsistent classification of unexplained sudden deaths in infants and children hinders surveillance, prevention and research: recommendations from The 3rd International Congress on Sudden Infant and Child Death.

This report details the proceedings and conclusions from the 3rd International Congress on Unexplained Deaths in Infants and Children, held November 26-27, 2018 at the Radcliffe Institute at Harvard University. The Congress was motivated by the increasing rejection of the diagnosis Sudden Infant Death Syndrome (SIDS) in the medical examiner community, leading to falsely depressed reported SIDS rates and undermining the validity and reliability of the diagnosis, which remains a leading cause of infant and child mortality. We describe the diagnostic shift away from SIDS and the practical issues contributing to it. The Congress was attended by major figures and opinion leaders in this area from countries significantly engaged in this problem. Four categories (International Classification of Diseases (ICD)-11 categories of MH11, MH12, MH14, PB00-PB0Z) were recommended for classification, and explicit definitions and guidance were provided for death certifiers. SIDS was reframed as unexplained sudden death in infancy or SIDS/MH11 to emphasize that either term signifies the lack of explanation following a rigorous investigation. A distinct category for children over the age of 1 was recommended (MH12). Definitions and exclusions were provided for the alternative categories of accidental asphyxia and undetermined. As recommended, unexplained sudden death in infancy or SIDS on a death certificate will code a unique, trackable entity, accurately reflecting the inability to determine a definitive explanation, while satisfying surveillance needs and reliable identification for research efforts. The conclusions will be submitted to the World Health Organization for inclusion in the upcoming ICD-11.

Continuing major inconsistencies in the classification of unexpected infant deaths.

The classification of the cause of unexpected infant deaths by both pathologists and researchers may be quite inconsistent. For example, if an infant is found lying face down on soft bedding the death may still be certified as 'sudden infant death syndrome (SIDS)', 'accidental suffocation', 'undetermined', 'unclassified sudden infant death (USID)', or 'sudden unexpected death in infancy (SUDI)'. As the San Diego definition of SIDS does not appear to be rigorously or consistently applied, clarifying 'mechanical asphyxia not determined with certainty' may help to more clearly separate SIDS from USID. Including a classification algorithm with the definition may also help to better define unsafe sleep factors and suffocation. This commentary reviews the current situation with regard to classifying these deaths and concludes that the absence of diagnostic pathological markers with conflicting classification systems has led to idiosyncratic certification practices.

National and State Trends in Sudden Unexpected Infant Death: 1990-2015.

BACKGROUND: Sharp declines in sudden unexpected infant death (SUID) in the 1990s and a diagnostic shift from sudden infant death syndrome (SIDS) to unknown cause and accidental suffocation and strangulation in bed (ASSB) in 1999-2001 have been documented. We examined trends in SUID and SIDS, unknown cause, and ASSB from 1990 to 2015 and compared state-specific SUID rates to identify significant trends that may be used to inform SUID prevention efforts. METHODS: We used data from US mortality files to evaluate national and state-specific SUID rates (deaths per 100 000 live births) for 1990-2015. SUID included infants with an underlying cause of death, SIDS, unknown cause, or ASSB. To examine overall US rates for SUID and SUID subtypes, we calculated the percent change by fitting Poisson regression models. We report state differences in SUID and compared state-specific rates from 2000-2002 to 2013-2015 by calculating the percent change. RESULTS: SUID rates declined from 154.6 per 100 000 live births in 1990 to 92.4 in 2015, declining 44.6% from 1990 to 1998 and 7% from 1999 to 2015. From 1999 to 2015, SIDS rates decreased 35.8%, ASSB rates increased 183.8%, and there was no significant change in unknown cause rates. SUID trends among states varied widely from 41.5 to 184.3 in 2000-2002 and from 33.2 to 202.2 in 2013-2015. CONCLUSIONS: Reductions in SUID rates since 1999 have been minimal, and wide variations in state-specific rates remain. States with significant declines in SUID rates might have SUID risk-reduction programs that could serve as models for other states.

Neuronal apoptosis in the brainstem medulla of sudden unexpected death in infancy (SUDI), and the importance of standardized SUDI classification.

The purpose of this study was to examine the neuronal expression of apoptotic markers in the rostral medulla of a newly characterized dataset of sudden unexpected death in infancy (SUDI), and to determine the impact of diagnostic groupings on these findings and whether they pertain to the intrinsic apoptotic pathway. Immunohistochemical staining was quantified to determine the percentage of neurons positive for active caspase-9 (specific to the intrinsic apoptotic pathway), active caspase-3 (common to the intrinsic and extrinsic apoptotic pathways) and Terminal deoxynucleotidyl transferase mediated dUTP nick-end labelling (TUNEL) (labels DNA fragmentation) in nine nuclei of the rostral medulla. Expression was compared between groups of SUDI infants where the cause of death was initially classified by a forensic pathologist or subsequently after reclassification by an expert panel using the San Diego Criteria. 68 SUDI infants were studied and originally classified as explained SUDI (n = 12), Sudden Infant Death Syndrome (SIDS) (n = 27) and undetermined (n = 29). Reclassification resulted in a decrease in the number of explained SUDI cases to 7 and a decrease in the number of undetermined cases to 4, with a corresponding increase in the number of SIDS cases to 57 (8 SIDS I; 49 SIDS II). The expression of apoptotic markers was similar in explained SUDI and SIDS I infants. However, TUNEL expression was greater in the cuneate (p < 0.001), vestibular (p = 0.01) and hypoglossal (p < 0.001) nuclei and active caspase-3 expression was lower in the arcuate nucleus (p = 0.037) in SIDS II compared to explained Sudden Unexpected Death in Infancy (eSUDI) infants. Compared to SIDS I infants, SIDS II infants had greater TUNEL expression in the dorsal motor nucleus of the vagus (p < 0.01) and greater active caspase-9 expression in the medial and spinal vestibular nuclei (p = <0.01). Changes in apoptotic expression predominated in SIDS II infants. We postulate that these are due to a combination of contributing risk factors including the presence of an upper respiratory tract infection and bed-sharing/co-sleeping. The absence of changes in active caspase-9 expression compared to eSUDI indicates that the intrinsic apoptotic pathway is not upregulated in SIDS.

The Evolving Understanding of Sudden Unexpected Infant Death.

Sudden unexpected infant death (SUID) is the leading cause for post-neonatal mortality in industrialized nations. Case-control studies have identified risk factors for SUID that have shaped research into studies of causation. Most current hypotheses for the mechanisms for SUID contribute to the "SUID sequence"-hypoxia and/or hypercarbia in sleep to which a vulnerable infant fails to respond adequately and that results in death. Reducing vulnerability in infants and promoting safe sleep for infants is important for prevention and requires knowledge of the prevalence of risk factors within the target population and a culturally sensitive approach. [Pediatr Ann. 2017;46(8):e278-e283.].

Brief resolved unexplained event: New diagnosis in infants.

QUESTION: For many years, the term apparent life-threatening event (ALTE) was associated with sudden infant death syndrome, and parents who described an acute event in their infants were sent to the hospital for admission. I understand that for infants new terminology is recommended. What is the current approach to a near-death experience of an infant? ANSWER: A recent clinical practice guideline revised the name and definition of an ALTE to a brief resolved unexplained event (BRUE). The diagnosis of BRUE in infants younger than 1 year of age is made when infants experience 1 of the following BRUE symptoms: a brief episode (ie, less than 1 minute and usually less than 20 to 30 seconds) that is entirely resolved (infant is at baseline), which remains unexplained after the history and physical examination are completed, and includes an event characterized by cyanosis or pallor; absent, decreased, or irregular breathing; hypertonia or hypotonia; or altered responsiveness. Low-risk infants should not be admitted to the hospital and overtesting is discouraged.

Oral care and nosocomial pneumonia: a systematic review / Cuidados bucais e pneumonia nosocomial: revisão sistemática

To perform a systematic review of the literature on the control of oral biofilms and the incidence of nosocomial pneumonia, in addition to assessing and classifying studies as to the grade of recommendation and level of evidence. The review was based on PubMed, LILACS, and Scopus databases, from January 1st, 2000 until December 31st, 2012. Studies evaluating oral hygiene care related to nosocomial infections in patients hospitalized in intensive care units were selected according to the inclusion criteria. Full published articles available in English, Spanish, or Portuguese, which approached chemical or mechanical oral hygiene techniques in preventing pneumonia, interventions performed, and their results were included. After analysis, the articles were classified according to level of evidence and grade of recommendation according to the criteria of the Oxford Centre for Evidence-Based Medicine. A total of 297 abstracts were found, 14 of which were full articles that met our criteria. Most articles included a study group with chlorhexidine users and a control group with placebo users for oral hygiene in the prevention of pneumonia. All articles were classified as B in the level of evidence, and 12 articles were classified as 2B and two articles as 2C in grade of recommendation. It was observed that the control of oral biofilm reduces the incidence of nosocomial pneumonia, but the fact that most articles had an intermediate grade of recommendation makes clear the need to conduct randomized controlled trials with minimal bias to establish future guidelines for oral hygiene in intensive care units.

Apresentar revisão sistemática da literatura sobre o controle do biofilme bucal e a incidência da pneumonia nosocomial, avaliando e classificando os estudos quanto ao grau de recomendação e ao nível de evidência científica. A revisão foi realizada nas bases PubMed, LILACS e Scopus, de 1 o de janeiro de 2000 até 31 de dezembro de 2012. Foram selecionados os estudos que avaliaram os cuidados com higiene bucal relacionando-os com infecções nosocomiais em paciente internados em unidades de terapia intensiva, seguindo os critérios de inclusão. Foram incluídos artigos na íntegra publicados em inglês, espanhol ou português, que abordavam alguma técnica de higiene bucal, química ou mecânica, na prevenção de pneumonia, as intervenções executadas e os resultados. Após análise dos dados, os artigos foram classificados quanto ao nível de evidência e o grau de recomendação, de acordo com os critérios da Oxford Centre for Evidence-Based Medicine. Foram encontrados 297 resumos e, destes, 14 artigos na íntegra contemplaram nossos critérios. A maioria dos artigos incluía um grupo de estudo com uso de clorexidina e um controle com o uso de placebo para higiene bucal na prevenção de pneumonia. Quanto ao nível de evidência, todos os artigos foram classificados como B; quanto ao grau de recomendação, 12 artigos foram classificados como 2B e 2 como 2C. O controle do biofilme bucal reduz a incidência de pneumonia nosocomial, porém o nível de evidência e o grau de recomendação intermediário deixam evidente a necessidade da elaboração de estudos clínicos randomizados controlados com viés mínimo para estabelecer futuros protocolos para higiene bucal em unidades de terapia intensiva.

Assigning cause for sudden unexpected infant death.

We have reached a conundrum in assigning cause of death for sudden unexpected infant deaths. We summarize the discordant perspectives and approaches and how they have occurred, and recommend a pathway toward improved consistency. This lack of consistency affects pediatricians and other health care professionals, scientific investigators, medical examiners and coroners, law enforcement agencies, families, and support or advocacy groups. We recommend that an interdisciplinary international committee be organized to review current approaches for assigning cause of death, and to identify a consensus strategy for improving consistency. This effort will need to encompass intrinsic risk factors or infant vulnerability in addition to known environmental risk factors including unsafe sleep settings, and must be sufficiently flexible to accommodate a progressively expanding knowledge base.

Classification system for the Sudden Unexpected Infant Death Case Registry and its application.

Sudden unexpected infant deaths (SUID) accounted for 1 in 3 postneonatal deaths in 2010. Sudden infant death syndrome and accidental sleep-related suffocation are among the most frequently reported types of SUID. The causes of these SUID usually are not obvious before a medico-legal investigation and may remain unexplained even after investigation. Lack of consistent investigation practices and an autopsy marker make it difficult to distinguish sudden infant death syndrome from other SUID. Standardized categories might assist in differentiating SUID subtypes and allow for more accurate monitoring of the magnitude of SUID, as well as an enhanced ability to characterize the highest risk groups. To capture information about the extent to which cases are thoroughly investigated and how factors like unsafe sleep may contribute to deaths, CDC created a multistate SUID Case Registry in 2009. As part of the registry, the Centers for Disease Control and Prevention developed a classification system that recognizes the uncertainty about how suffocation or asphyxiation may contribute to death and that accounts for unknown and incomplete information about the death scene and autopsy. This report describes the classification system, including its definitions and decision-making algorithm, and applies the system to 436 US SUID cases that occurred in 2011 and were reported to the registry. These categories, although not replacing official cause-of-death determinations, allow local and state programs to track SUID subtypes, creating a valuable tool to identify gaps in investigation and inform SUID reduction strategies.

A re-audit of the use of definitions of sudden infant death syndrome (SIDS) in peer-reviewed literature.

The use of different definitions of sudden infant death syndrome (SIDS) may make comparison of data among studies difficult. Fifty randomly selected papers dealing with SIDS that were published between 2010 and 2011 in peer-reviewed journals were reviewed to determine whether one of three internationally accepted definitions of SIDS had been either written in the text or referenced. A significant improvement in the use of definitions has occurred since 2005, with the percentage of papers either quoting or referencing a standard definition increasing by 26%, from 42 to 68%. The 1989 NICHD definition remained the most commonly used definition (35.1%) followed by the 2004 San Diego definition (26.3%). Although the percentage of papers where either no definition was provided or where an idiosyncratic or mis-cited definition was used fell 26%, from 58 to 32%, nearly one in three papers published on SIDS in peer-reviewed journals that were included in this study still did not cite a standard definition.

Application of a classification system focusing on potential asphyxia for cases of sudden unexpected infant death.

Current classification schemes for sudden unexpected infant death (SUID) may not be optimal for capturing scene events that potentially predispose to asphyxia. (1) To compare causes of death in a group of SUID cases assigned by multiple reviewers using our recently published classification scheme for SUID that is based on asphyxial risk at the death scene, and (2) To compare these newly assigned causes of death to that originally assigned by the medical examiners of record who performed the autopsies. Five reviewers independently assigned causes of death for 117 cases of SUID, including 83 originally diagnosed as sudden infant death syndrome (SIDS), accessioned into the San Diego SIDS/SUDC Research Project from the San Diego County Medical Examiner's Office. The diagnostic categories are: A: SIDS; B: Unexplained-Potentially Asphyxia; C: Unexplained-Other Potential Causes of Death; D: Unclassified-Other; E: Unclassified; and F: Known Cause of Death. The reviewers collectively opined that conditions at the death scene contributed to or caused death in 32-50% of all of the 117 cases as well as in 40-59% of the 83 originally diagnosed SIDS cases. Another cause of death was considered plausible in 2-12% of the SIDS cases. Application of this new classification system resulted in 55-69% decrease in SIDS diagnoses. Asphyxia as a potential contributor to, or as the specific cause of death, appears to exist in a large percentage of cases designated as SIDS using other classification schemes. When certifiers use a classification system that focuses upon potential asphyxia in determining the cause of death the incidence of SIDS dramatically declines.

Differentiating cause-of-death terminology for deaths coded as sudden infant death syndrome, accidental suffocation, and unknown cause: an investigation using US death certificates, 2003-2004.

We compared written text on infant death certificates for deaths coded as sudden infant death syndrome (R95), unknown cause (R99), and accidental suffocation (W75). Using US mortality files supplemented with the death certifiers' written text for all infant deaths with International Classification of Diseases (ICD)-10 assigned codes R95, R99, and W75, we formed cause-of-death subcategories from common themes identified from the written text. Among all infant deaths in 2003-2004, the underlying cause of death was listed as R99 for 2128 deaths, R95 for 4408 deaths, and W75 for 931 deaths. Among the postneonatal deaths, the differences in subcategories varied between assigned ICD-10 codes: for R99-coded deaths, 45.8% were categorized as "Unknown" and 48.6% as "Pending"; for R95-coded deaths, 67.7% were categorized as "sudden infant death syndrome (SIDS)"; and for W75-coded deaths, 76.4% were categorized as "Suffocation." Examination of the written text on the death certificates demonstrates variability in the assigned ICD-10 codes which could have an important effect on the estimates of SIDS cases in the United States.