Toxicology and sudden infant death

One hundred thirty cases of sudden infant death occurring in Wayne County, Michigan, (population 2.7 million) were analyzed for possible drugs. The toxicological protocol has been outlined. Six cases were found to be positive, and in five of these the drugs found had been prescribed for a variety of illnesses. In one case methadone was found in the blood of an infant whose mother was undergoing methadone treatment for drug addiction, the drug being transmitted through breast milk. In none of the 102 cases of sudden infant death syndrome (SIDS) included in the study did the toxicological results affect the diagnosis. In our study, toxicological analyses never contradicted an initial diagnosis of SIDS, and, therefore, we feel that this diagnosis should be made promptly based on investigative and autopsy findings.     

Melatonin concentrations in the sudden infant death syndrome

To examine a possible relationship between pineal function and the sudden infant death syndrome (SIDS), samples of whole blood, ventricular cerebrospinal fluid (CSF) and/or vitreous humor (VH) were obtained at autopsy from 68 infants (45 male, 23 female) whose deaths were attributed to either SIDS (n = 32, 0.5-5.0 months of age; mean +/- S.E.M., 2.6 +/- 0.2 months) or other causes (non-SIDS, n = 36, 0.3-8.0 months of age 4.3 +/- 0.3 months). The melatonin concentrations were measured by radioimmunoassay. A significant correlation was observed for melatonin levels in different body fluids from the same individual. After adjusting for age differences, CSF melatonin levels were significantly lower among the SIDS infants (91 +/- 29 pmol/l; n = 32) than among those dying of other causes (180 +/- 27; n = 35, P less than 0.05). A similar, but non-significant trend was also noted in blood (97 +/- 23, n = 30 vs. 144 +/- 22 pmol/l, n = 33) and vitreous humor (68 +/- 21, n = 10 vs. 81 +/- 17 pmol/l, n = 15). These differences do not appear to be explainable in terms of the interval between death and autopsy, gender, premortem infection or therapeutic measures instituted prior to death. Diminished melatonin production may be characteristic of SIDS and could represent an impairment in the maturation of physiologic circadian organization.     

Pathology of sudden infant death syndrome

This study is based on 15 cases examined by the author. The majority of the infants were found in a prone position. Thymus was enlarged in all cases. Its enlargement of the lower portion overlying the basal portion of the heart formed an unyielding, tense membrane. In prone position, the heavy ventricles fell forward, producing angulation and kinking against this membrane and inhibited the filling of the heart or irritated the heart, producing arrhythmia and cardiac arrest.     

Cardiac lesions in sudden infant death syndrome

Sequential morphological changes as found in the hearts of 250 sudden infant death syndrome (SIDS) infants are described. Detailed examination of macroscopic and microscopic lesions reveal that all SIDS infants had identifiable lesions at the time of their death. The lesions can best be described as selective focal anoxic muscle fibre necrosis at chronologically different developmental stages. The extent of these lesions vary markedly from case to case, from a minimal muscle fibre eosinophilia through contraction band formation, myocytolysis, stromal condensation to scar formation. The morphological variations in the lesions amongst individual cases can be interpreted as relating to the time interval of the development of the lesions. The intramural and coronary arteries in some cases are also affected showing intimal hyperplasia. Although these sequential morphological aberrations are not specific and typical to SIDS infants only, they were present in all SIDS infants in this series.     

婴儿猝死综合征的研究现状及其法医学检验

婴儿猝死综合征(dudden infant death s yndrome,SIDS)一直是法医学和儿科学领域的研究热点。相对于北美、欧洲、澳洲以及日本等地对SIDS广泛深入的研究,来自中国的报道相对较少。本文通过总结文献,介绍SIDS的发展历史、研究现状和新的发展趋势,并结合2004年各国学者在美国圣地亚哥公布的SIDS分型,讨论实际检案中需注意的问题以及推进其调查研究的可行性。     

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.     

Histologic findings in the lung in sudden infant death

The lungs of 79 children who had died between the ages of 1 week and 2 years old were histologically examined. 59 of these children could be categorized as cases of Sudden Infant Death because of the history and postmortem findings. In the remaining 20 cases a definite cause of death could be established. This is the same collective on which the histological investigations of the lymphatic tissue has been carried out. Morphological changes which are typical for a virus pneumonia were found in a substantially higher frequency in the cases of Sudden Infant Death than in the control cases. The validity of these findings and their possible significance for the cause of death are discussed.     

婴幼儿猝死综合征神经病理学的研究进展

婴幼儿猝死综合征(SIDS)是指发生于1岁以内婴儿无明显病因的突然死亡,其死亡原因及鉴别诊断标准迄今仍不明确。本文参考了近年来采用免疫组化方法对SIDS神经系统病理变化的研究文献,提出SIDS致命的病理生理机制是与睡眠相关的呼吸循环失控或衰竭,即SIDS的主要病因存在于中枢神经系统,但不是单一病因。     

Age-dependent morphologic findings of the thyroid in sudden infant death

Age (eight days to 12 months) and degree of colloid depletion or colloid content of the follicles (normal, partially depleted, depleted) were correlated on the basis of 176 thyroid investigations in cases of sudden infant death syndrome (SIDS). In the 176 SIDS cases, a resting thyroid gland with normal colloid content could only be found in 14%, whereas partially depleted follicles were found in 35% and depleted follicles in 51%. 60% of all cases showed a large degree of epithelial desquamation up to collapse of all follicles. A marked capillary hyperemia was found in 48%. 80% of the cases showed a normal colloid content in the first month of life, and colloidfree follicles should not be detected in any case. An increased incidence of thyroid activation was obtained in the total number of cases only from the second month of life. The histomorphological appearance of the thyroid gland thus corresponds to that of healthy infants only in the first month of life. The question as to why there is an evidently raised thyroid activity in the subsequent months of life in SIDS cases is discussed.     

The fallacy of the simultaneous sudden infant death syndrome in twins

The likelihood of twin infants dying suddenly and simultaneously of SIDS, a natural disorder, defies credibility. However, injuries associated with environmental hazards provide possible mechanisms of sudden death. A search for hazards in the homes of 13 pairs of healthy twins who died together of no apparent cause formed the basis of this study. Ten of the 13 sets were certified by medical examiners as simultaneous twin SIDS. The findings in this study suggest that all 13 sets died from injuries, either unintentional or otherwise, and that these deaths could have been prevented.     

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.     

Cardiac rhabdomyoma presenting as sudden infant death syndrome

A case of cardiac rhabdomyoma presenting as sudden infant death in a four-and-one-half month-old infant is reported. The child was the product of an essentially uncomplicated pregnancy and enjoyed good health before his unexpected, sudden death. Autopsy examination revealed the presence of multiple cardiac lesions which histologically were diagnosed as rhabdomyomas. Death was attributed to fatal cardiac arrhythmia caused by the tumor. To the authors' knowledge this represents the first reported case in the forensic science literature of death as a result of cardiac rhabdomyoma presenting as sudden infant death syndrome (SIDS).     

Desquamative interstitial pneumonia in an infant. Mimicry of sudden infant death syndrome

A 15-week-old infant girl, without a prior history of overt illness, was found dead while sleeping between her two parents. The gross examination at autopsy showed only congested lungs, and the initial diagnosis was sudden infant death (SID). On microscopic examination, a desquamative interstitial pneumonia (DIP) was observed. The widespread, patchy intraalveolar histiocytic desquamation was associated with lymphocytic infiltration of bronchiolar and aveolar walls, which together provided convincing evidence that an interstitial pneumonitis was the cause of death. A viral etiology seems most likely in view of the accompanying chronic inflammation of bronchial submucosal glands.     

Immunohistochemical techniques improve the diagnosis of myocarditis in cases of suspected sudden infant death syndrome (SIDS)

Immunohistochemical techniques have improved the diagnosis of myocarditis. In a post mortem study, eight specimens in each case of the formalin-fixed and paraffin-embedded hearts of 20 suspected cases of sudden infant death syndrome (SIDS) were investigated with traditional hematoxylin-eosin staining and immunohistochemical methods. The hematoxylin-eosin stained specimens were examined for myocarditis according to the Dallas criteria; only in one case was a myocarditis diagnosed. The subsequent definition of the major histocompatibility complex class II antigens (HLA-DP,DQ,DR and HLA-DR), known to be enhanced in cases of myocarditis, the quantification of leucocytes with leucocyte common antigen (LCA) and characterization and quantification of T-lymphocytes using a specific marker (CD-3) allowed the definite diagnosis of myocarditis in three additional cases, six cases were found with moderate changes and ten cases without signs of inflammation.     

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.