Investigation of sudden infant deaths in the State of Maryland (1990-2000)

The Office of the Chief Medical Examiner (OCME) has recorded a significant decline in the deaths of sudden infant death syndrome (SIDS) in the state of Maryland since 1994. However, infants who died of accidental or non-accidental injuries remained consistent during the same time period. This report focuses on the epidemiological characteristics and scene investigation findings of infant victims who died suddenly and unexpectedly in Maryland between 1990 and 2000. A retrospective study of OCME cases between 1990 and 2000 yielded a total of 1619 infant fatalities. 802 infant deaths were determined to be SIDS, which represented 50% of the total infant deaths in our study population. Five hundred and twenty-three (31.8%) deaths were due to natural diseases, 128 (7.9%) deaths were accidents, and 74 (4.6%) were homicides. The manner of death could not be determined after a thorough scene investigation, review of history and a complete postmortem examination in 92 (5.7%) infants. SIDS deaths most often involved infants who were male and black. The peak incidence of SIDS was between 2 and 4 months of age. The majority of SIDS infants (60%) were found unresponsive on their stomach. Among SIDS infants, 269 (33.4%) were found in bed with another person or persons (bed sharing). Of the bed-sharing SIDS cases, 182 (68%) were African-American. In the past 11 years, 52 infants died of asphyxia due to unsafe sleeping environment, such as defective cribs, ill-fitting mattresses, inappropriate bedding materials. Of the 74 homicide victims, 53 (70%) involved infants less than 6 months of age. Twenty (27%) exhibited the classical abuse syndrome characterized by repeated acts of trauma to the infants.     

Sudden infant death syndrome risk factors with regards to sleep position, sleep surface, and co-sleeping

We present a study of 102 Sudden Infant Death Syndrome (SIDS) deaths using a retrospective review of medical examiner autopsy reports. The prevalence of sleep related risk factors with regards to sleep surface, sleep position, and co-sleeping were determined in a population of infants less than 1-year-old. Of the 102 SIDS deaths, 67 (65.7%) were not in a crib, 63 (61.8%) were prone, and 48 (47.1%) were co-sleeping. However, 94 (92.2%) of these deaths had at least one risk factor present. Only 8 (7.8%) infants had slept alone, in a crib or bassinet, and on their back or side. Infants less than 4-months-old had a higher rate of co-sleeping (54.7%) than the older infants (25.9%), and a higher frequency of heart malformations at post-mortem examination. The older infants were more likely to exhibit pulmonary and tracheal inflammation, and neuropathology.     

A deadly anti-SIDS device

The diagnosis of sudden infant death syndrome (SIDS) has been an enigma to medical examiners and coroners for decades. The recent drastic decrease in the number of SIDS cases has been associated with infants sleeping supine instead of prone. The apparent relation between sleeping position and SIDS has led to the marketing of several positioning sleep aids. We report a case of the improper use of one such device which resulted in the death of an infant.     

Changing trends in the diagnosis of sudden infant death

A study of 114 consecutive cases of unexpected infant death that occurred in South Australia over a 5-year period from January 1994 to December 1998 was undertaken. There were 45 deaths attributed to sudden infant death syndrome (SIDS), 19 to natural causes, 21 to accidents. and 5 to homicides; 24 cases were listed as "undetermined." Although there has been a genuine and continued decline in SIDS numbers in this population, there has also been an increase in the diagnosis of cases of accidental asphyxia due to unsafe sleeping environments and of cases in which the family background and autopsy findings suggested more complex mechanisms. The change in diagnostic profile has followed the introduction of more rigorous clinical history review, death scene examination, and autopsy testing. Thus, although diagnostic outcomes have altered in this population, it is more likely the result of more careful interpretation of the extensive investigations that are now undertaken rather than arbitrary reclassification.     

Sudden infant death syndrome: diagnostic practices and investigative policies, 2004

Using a 2004 population-based survey of all US medical examiner and coroner offices, we examined the characteristics of offices accepting an infant death case and calculated the percentage of offices that had death scene investigation or autopsy policies for the investigation of sudden unexpected infant death (SUID). We also calculated the percentage of offices that used and did not use sudden infant death syndrome (SIDS) as a cause of death, and we compared differences in characteristics among those offices.Of medical examiner and coroner offices, 52% did not report an infant death in 2004. Of the 7957 infant deaths reported, 43% occurred in jurisdictions that experienced 1 or 2 infant deaths. Of the offices that used SIDS as a classification, 34% did not have policies for conducting death scene investigations and autopsies for SUID. At least 5% of offices that reported an infant death did not use SIDS as a cause of death classification. These findings have important implications for understanding recent trends in SIDS and SUID. Supporting the implementation of national standards for investigating and certifying infant deaths could provide guidelines for consistent practices in medical examiner and coroner offices.     

A comparison of pulmonary intra-alveolar hemorrhage in cases of sudden infant death due to SIDS in a safe sleep environment or to suffocation

The differentiation of SIDS from accidental or inflicted suffocation may be impossible without corroborating findings from the death scene or autopsy or in the absence of a confession from a perpetrator. Pulmonary intra-alveolar hemorrhage (PH) has been proposed as a potential clue to suffocation, but none of the previous studies on this topic have limited SIDS cases to those who were in a safe sleep environment, in which all were found supine and alone on a firm surface with their heads uncovered. Our aims are to: (1) compare PH in SIDS cases found in a safe sleep environment to a control group comprised of infants whose deaths were attributed to accidental or inflicted suffocation and (2) assess the effect of age, CPR, and postmortem interval (PMI), with regard to the severity of PH in this subset of safe-sleeping SIDS cases. We conducted a retrospective study of all postneonatal cases accessioned by the Office of the Medical Examiner in San Diego County, California who died of SIDS or suffocation between 1999 and 2004. A total of 74 cases of sudden infant death caused by SIDS (34 cases as defined above, comprising 8% of the total SIDS cases), accidental suffocation (37), and inflicted suffocation (3) from the San Diego SIDS/SUDC Research Project database were compared using a semiquantitative measure of pulmonary intra-alveolar hemorrhage. The most severe (grade 3 or 4) PH occurred in 35% of deaths attributed to suffocation, but in only 9% of the SIDS cases. Age, duration of CPR attempts and PMI had no effect on the severity of PH in SIDS. Our results indicate that the severity of PH cannot be used independently to differentiate SIDS from suffocation deaths. Each case must be evaluated on its own merits after thorough review of the medical history, circumstances of death, and postmortem findings.     

Oronasal blood in sudden infant death.

Oronasal secretions are observed frequently in sudden infant death syndrome (SIDS), but overt blood is uncommonly reported. The literature on oronasal blood in sudden infant death is limited. The goal of this study was to determine the frequency of oronasal blood in sudden infant deaths and to examine possible causative factors. Oronasal blood was described in 28 (7%) of 406 cases of sudden infant death. Oronasal blood could not be attributed to cardiopulmonary resuscitation in 14 cases, including 10 (3%) of 300 cases of SIDS, 2 (14%) of 14 accidental suffocation cases, and 2 (15%) of 13 undetermined cases. Eight of the 10 infants in cases of sudden infant death were bedsharing: 5 with both parents, 2 between both parents. The infant in 1 SIDS case was from a family that had had three referrals to Child Protective Services. Oronasal blood not attributable to cardiopulmonary resuscitation occurs rarely in SIDS when the infant is sleeping supine in a safe environment. Bedsharing may place infants at risk of suffocation from overlaying. Oronasal blood observed before cardiopulmonary resuscitation is given is probably of oronasal skin or mucous membrane origin and may be a sign of accidental or inflicted suffocation. Sanguineous secretions that are mucoid or frothy are likely of remote origin, such as lung alveoli. The use of an otoscope to establish the origin of oronasal blood in cases of sudden infant death is recommended.     

Nonnatural death masquerading as SIDS (sudden infant death syndrome)

This article relates our experiences with accidental and homicidal deaths in reported sudden infant death syndrome (SIDS) cases. Our intent is to alert personnel in medical and health-related professions as well as death investigators (coroners, law enforcement officials, etc.) that a thorough scene investigation and history need to be obtained when a child's death has been reported, since this may modify the type of autopsy to be performed. It should not be assumed that all children less than 1 year of age who die suddenly die from SIDS.     

Homicide as a cause of the sudden infant death syndrome

The homicidal asphyxiation of a 10 1/2-month-old male infant and the attempted asphyxiation of his 4-month-old sibling, documented by parental confession, is presented as evidence that murder may sometimes be mistaken as sudden infant death syndrome (SIDS). A review of the literature of the relationship between murder and SIDS deaths reveals the suspicions of some physicians but few published cases; this reflects not only the difficulties of making a determination of murder by suffocation, since no injuries may be present, but also a lack of awareness among physicians who must evaluate infant deaths. It is recommended that murder should be considered in the differential diagnosis of sudden, unexpected death in infants and that the autopsy should include full-body x-rays and at least an initial look at the social history of the child.     

Infant death scene investigation and the assessment of potential risk factors for asphyxia: a review of 209 sudden unexpected infant deaths

At the Wayne County Medical Examiner Office (WCMEO) in Detroit, Michigan, from 2001 to 2004, thorough scene investigations were performed on 209 sudden and unexpected infant deaths, ages 3 days to 12 months. The 209 cases were reviewed to assess the position of the infant at the time of discovery and identify potential risk factors for asphyxia including bed sharing, witnessed overlay, wedging, strangulation, prone position, obstruction of the nose and mouth, coverage of the head by bedding and sleeping on a couch. Overall, one or more potential risk factors were identified in 178 of 209 cases (85.2%). The increasing awareness of infant positions at death has led to a dramatic reduction in the diagnosis of sudden infant death syndrome at the WCMEO. This study suggests that asphyxia plays a greater role in many sudden infant deaths than has been historically attributed to it.     

Sudden infant death syndrome: a subject of medicolegal research

During the last decade, much attention has been paid to the risk factors of sudden infant death syndrome (SIDS). Many researchers have demonstrated that infant-care practices are linked to the risk of SIDS. Prone sleeping, bed sharing, maternal substance abuse, and cigarette smoking have been reported to be significant potentially modifiable risk factors for SIDS. Despite the reports that the incidence of SIDS has decreased by 38% in the United States, it remains the leading cause of death in the first year of life. Deaths resulting from child abuse or neglect inflicted or permitted by their caretakers being second only to SIDS in infant mortalities and some recommendations regarding the differentiation of SIDS and child abuse have generated speculation that some cases of infanticide were misdiagnosed as SIDS. To reach a proper conclusion as to the cause and manner of death of an infant who died suddenly and unexpectedly, investigation must be thorough and professional.     

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.     

Evaluation of diagnostic tools applied in the examination of sudden unexpected deaths in infancy and early childhood

During the period between 1984 and 1999, 309 cases of sudden unexpected death in infancy and early childhood (0-3 years) were investigated at the Institute of Forensic Medicine in Oslo. In 73 cases, an explainable cause of death was found. In this non-sudden infant death syndrome (SIDS) group, 42 cases were due to disease, 14 to accidents, 7 to neglect/abuse and 10 cases were due to homicide. In 43 cases, there were pathological findings at the autopsy or suspect features in the history and/or circumstances, which were, however, insufficient to explain death ("borderline" SIDS). In the remaining 193 cases, nothing of significance was detected ("pure" SIDS).The purpose of the present study was to evaluate the importance of the different diagnostic tools used in diagnosing non-SIDS and borderline SIDS cases. The definition of SIDS requires a negative history as well as a negative autopsy result. Thus, the following variables were analysed: circumstances, medical history and autopsy, which included a gross pathological investigation, histology, neuropathology, microbiology, radiology and toxicology. In diagnosing deaths due to disease, histology, neuropathology and microbiology were the most important diagnostic tools. In contrast, information about the circumstances of death and the gross pathological findings at autopsy most often revealed the cause of death in accidents and cases of neglect/abuse and homicide.Following the drop in SIDS rate in Norway after 1989, the share of pure SIDS in proportion to the total population of sudden unexpected deaths in infancy and early childhood has decreased. The increasing proportion of non-SIDS and borderline SIDS cases presents a challenge to improve the quality of the investigation in cases of sudden death in infancy and early childhood.     

Toxicologic analysis in cases of possible sudden infant death syndrome: a worthwhile exercise?

The diagnosis of sudden infant death syndrome (SIDS) is one of exclusion. At the Department of Forensic Medicine, Westmead Hospital, toxicologic analysis is performed as part of the postmortem examination of all apparent SIDS deaths. The results for the 5-year period January 1, 1994, to December 31, 1999, were audited to determine whether such routine testing was worthwhile. During this time there were 117 cases with a history consistent with SIDS. Drugs were detected in 19 (16%) of these cases. In 1 case, death was attributed to the finding of methadone. The presence of methadone was regarded as a possible contributing factor to death in a further 2 cases. The presence of possible methadone toxicity had not been expected from the history given before the examination in these 3 cases. In 114 cases there was a suitable sample for alcohol testing; in no case was alcohol detected. In 13 cases the postmortem examination revealed an anatomic cause of death (including 3 cases consistent with whiplash/shaken baby/impact head injury), which excluded a diagnosis of SIDS. In conclusion, routine toxicologic testing in all possible cases of SIDS death supplements the postmortem examination in excluding cases of non-SIDS.     

Natural death as viewed by the medical examiner: a review of 1000 consecutive autopsies of individuals dying of natural disease

A study of 1000 consecutive autopsies of individuals dying of natural disease was conducted. Cardiovascular disease was responsible for 60.9% of all deaths with coronary artery disease--not only the main cause of cardiovascular death but also the main cause of all natural deaths--accounting for 45.1% of such cases. Diseases of the central nervous and respiratory systems accounted for 8.7 and 8.6%, respectively, of the natural deaths. Seizure disorders and pneumonia were the main causes of death in these organ systems. There were 124 deaths of children less than one year in age, 91 of which were due to sudden infant death syndrome (SIDS). All of the SIDS deaths were in children less than 10 months old.     

Delayed death in sudden infant death syndrome: a San Diego SIDS/SUDC Research Project 15-year population-based report

A fraction of SIDS cases have death delayed by successful CPR, yet they have not been compared to SIDS cases which were found dead or not successfully resuscitated. Our aims were to: (1) determine the percent of SIDS cases in the San Diego SIDS Research Project database for whom death was delayed by CPR and subsequent life support; (2) compare demographics, circumstances of death and autopsy findings of delayed death SIDS cases (delayed SIDS) with those whose deaths were not delayed (non-delayed SIDS); (3) examine the evolution of pathologic changes in delayed SIDS as a function of survival interval. A retrospective 15-year population-based study of 454 infant deaths attributed to SIDS revealed 29 delayed SIDS cases (Group I) and 425 non-delayed SIDS cases (Group II). Group I cases were significantly older than Group II cases (mean age 132 days vs. 102 days and p<0.0001). Eighty-nine percent of the Group I cases were discovered between 08.00 and 19.59 h; none were found between 00.00 and 07.59 h, compared to 38% of the Group II cases. Group I infants were found significantly more often away from home (at daycare, or at the home of a relative, friend, or baby sitter) than Group II infants (45% vs. 25%, p<0.05). There were no differences between groups with regard to gender, gestational age, type of delivery, bed sharing, URI within 48 h of death, ALTEs, a history of referral to child protective services, body position when placed or found, or face position when found. Pathologic changes were semiquantitatively evaluated; findings were characteristic of anoxic-ischemic injury that generally became more severe with increasing survival intervals. Anoxic-ischemic brain injury was the immediate cause of death in all delayed SIDS cases. Aspiration of gastric contents was identified in Group I cases surviving less than 48 h and was the likely etiology of acute bronchopneumonia occurring in 83% of the Group I cases. We did not identify factors that would reliably predict which SIDS cases might be discovered soon enough to allow earlier and more effective CPR and survival without permanent brain injury.     

Sudden infant death due to neurofibromatosis type I

Sudden infant death syndrome (SIDS) is the unexpected death of an infant under the age of 1 year, where a complete autopsy, including scene investigation, fails to reveal a cause of death. Although the frequency of SIDS has decreased almost 50% over the past 10 years, it remains the leading cause of death in infants aged 1 to 6 months. SIDS is a diagnosis of exclusion and requires the elimination of a wide range of possible causes, including asphyxia, poisoning, abuse, occult heart disease, and other natural disease processes. In this report, we describe the case of an infant death initially suspected to be a SIDS death in which autopsy revealed an optic pathway glioma (optic glioma or hypothalamic glioma) and other stigmata of neurofibromatosis type I.     

The Institution of a Standardized Investigation Protocol for Sudden Infant Death in the Eastern Metropole,Cape Town,South Africa,,

The rate for the sudden infant death syndrome (SIDS) in Cape Town, South Africa, is estimated to be among the highest in the world (3.41/1000 live births). In several of these areas, including those of extreme poverty, only sporadic, nonstandardized infant autopsy, and death scene investigation (DSI) occurred. In this report, we detail a feasibility project comprising 18 autopsied infants with sudden and unexpected death whose causes of death were adjudicated according to the 1991 NICHD definitions (SIDS, n = 7; known cause of death, n = 7; and unclassified, n = 4). We instituted a standardized autopsy and infant DSI through a collaborative effort of local forensic pathology officers and clinical providers. The high standard of forensic investigation met international standards, identified preventable disease, and allowed for incorporation of research. We conclude that an effective infant autopsy and DSI protocol can be established in areas with both high sudden unexpected infant death, and elsewhere. (SUID)/SIDS risk and infrastructure challenges.     

Infanticide: is its incidence among postneonatal infant deaths increasing?: an 18-year population-based analysis in California

The decline in the incidence of sudden infant death syndrome (SIDS) and recent recommendations regarding the differentiation of SIDS and child abuse has generated speculation that some cases of infanticide were misdiagnosed as SIDS. The aims of this study were to determine the change in incidences and proportions of postneonatal deaths from all causes, SIDS, and infanticide in California over an 18-year interval encompassing years before and after the Back to Sleep campaign. Selected postneonatal mortality data from 1981 through 1998 obtained from the California Department of Health Services were analyzed and graphically displayed. The total postneonatal mortality and incidence of SIDS deaths per 100,000 live births decreased 45% and 66%, respectively, during the study interval; the incidence of infanticide remained low. The ratio of infanticide to SIDS increased from 4.3 per 100 in 1981 to 10.2 per 100 in 1998. Infanticide deaths, as a percentage of the total number of postneonatal deaths, increased slightly from the first to the second half of the study interval but never rose above 3.2%. It is concluded that this increased percentage is due to a decrease in SIDS deaths and not to an actual increase in infanticide deaths.