Jeffrey J. Barnard

Deaths and injuries from house fires

BACKGROUND We sought to define the factors associated with house fires and related injuries by analyzing the data from population-based surveillance. METHODS For 1991 through 1997, we linked the following data for Dallas: records from the fire department of all house fires (excluding fires in apartments and mobile homes), records of patients transported by ambulance, hospital admissions, and reports from the medical examiner of fatal injuries. RESULTS There were 223 injuries (91 fatal and 132 nonfatal) from 7190 house fires, for a rate of 5.2 injured persons per 100,000 population per year. Rates of injury related to house fires were highest among blacks (relative risk, 2.8; 95 percent confidence interval, 2.1 to 3.6) and in people 65 years of age or older (relative risk, 2.6; 95 percent confidence interval, 1.9 to 3.5). Census tracts with low median incomes had the highest rates of injury related to house fires (relative risk as compared with census tracts with high median incomes, 8.1; 95 percent confidence interval, 2.5 to 32.0). The rate of injuries was higher for fires that began in bedrooms or living areas (relative risk, 3.7); that were started by heating equipment, smoking, or children playing with fire (relative risk, 2.6); or that occurred in houses built before 1980 (relative risk, 6.6). Injuries occurred more often in houses without functioning smoke detectors (relative risk, 1.5; 95 percent confidence interval, 1.0 to 2.4). The prevalence of functioning smoke detectors was lowest in houses in the census tracts with the lowest median incomes (P<0.001). CONCLUSIONS Rates of injuries related to house fires are highest in elderly, minority, and low-income populations and in houses without functioning smoke detectors. Efforts to prevent injuries and deaths from house fires should target these populations.

Death Due to Microvascular Occlusion in Sickle-Cell Trait Following Physical Exertion

The heterozygous condition characterized by the presence of hemoglobin AS (sickle-cell trait) occurs in approximately 8% of the American black population. Unlike the homozygous state (sickle-cell disease), sickle-cell trait is not widely recognized as a cause of life-threatening illness or death despite over 30 case reports describing fatal or serious complications of exercise in young black males with this condition. These reports identify heat stress, dehydration, viral illness, and poor physical conditioning as factors which may contribute to exertional rhabdomyolysis and sudden death, suggesting multifactorial etiology. However, since sickling is known to occur postmortem, it remains controversial as to whether the pathogenesis of these exercise related deaths involves microvascular obstruction by sickled erythrocytes. We describe three young black individuals with no significant past medical history who died following physical exertion. In all three cases, postmortem hemoglobin electrophoresis demonstrated hemoglobin AS. In none of the cases was the body temperature found to be elevated. These cases serve to remind the forensic community that, in the proper setting, sickle-cell trait must be viewed as a potentially fatal disorder.

Fatal anaphylaxis due to fire ant stings

Imported fire ants (Solenopsis invicta and Solenopsis richteri) are the source of a potentially lethal environmental hazard in the southeastern United States. Because of their resistance to natural and chemical control, fire ants can overwhelm their environment, causing destruction of land and animals. Fire ants can also cause a variety of health problems in humans, ranging from simple stings to anaphylaxis and death. We present a case of a 30-year-old woman who died of anaphylaxis following multiple fire ant stings. At autopsy, multiple skin lesions characteristic of those produced by fire ant stings were present on her arm. Postmortem blood samples were positive for imported fire ant venom-specific IgE antibodies (5654 ng/ml) and tryptase (12 ng/ml). Deaths caused by imported fire ant stings are rare but are likely to become more common as the fire ant population expands. In this report, we review deaths due to fire ant stings, discuss postmortem laboratory findings, and stress the importance of recognizing the characteristic skin lesions produced by fire ants.

Cellular characterization of adipose tissue from various body sites of women.

Adipose tissue is the primary site of estrogen biosynthesis in postmenopausal women. The two main histologic components of adipose tissue are mature adipocytes and fibroblasts. Aromatase P450 expressed in the fibroblast component of adipose tissue is responsible for catalyzing conversion of C19 steroids to estrogens. We previously have demonstrated that in women, aromatase expression in adipose tissue of various body sites increases with age and that aromatase expression in the hip is markedly higher than in the abdomen. To determine whether this age- and regional-dependent variation in aromatase expression is caused by an alteration in the ratio of fibroblasts to mature adipocytes, we collected sc adipose tissue samples from 19 women (age range: 21-93 yr) at the time of autopsy. Using a computerized image analysis system, we determined by morphometry the proportions of adipocytes, fibroblasts, and vascular endothelial cells within histologic sections of adipose tissue from midabdomen, both breasts, and both hips. The percentage of each cell component at each body site was expressed as the mean of triplicate replicates. Statistical analysis of our results did not indicate any correlation between advancing age and fibroblast to adipocyte ratios in the breast, abdomen, or hip. Fibroblast to adipocyte ratios were found to be significantly higher in the breast and abdomen compared with the hip ( P < 0.05). No statistical differences were found between the breast and abdomen. These findings suggest that the increase in aromatase expression with advancing age and the higher aromatase expression in the hip compared with the abdomen in women may be caused by alterations in specific signal transduction mechanisms rather than a simple increase in local adipose fibroblast numbers.

Familial filicide and filicide classification.

Filicide is the killing of a child by his or her parent. Despite the disturbing nature of these crimes, a study of filicide classification can provide insight into their causes. Furthermore, a study of filicide classification provides information essential to accurate death certification. We report a rare case of familial filicide in which twin sisters both attempted to kill their respective children. We then suggest a detailed classification of filicide subtypes that provides a framework of motives and precipitating factors leading to filicide. We identify 16 subtypes of filicide, each of which is sufficiently characteristic to warrant a separate category. We describe in some detail the characteristic features of these subtypes. A knowledge of filicide subtypes contributes to interpretation of difficult cases. Furthermore, to protect potential child homicide victims, it is necessary to know how and why they are killed. Epidemiologic studies using filicide subtypes as their basis could provide information leading to strategies for prevention.

Sudden Death Due to Asphyxia by Esophageal Polyp: Two Case Reports and Review of Asphyxial Deaths

Asphyxia, not an uncommon cause of sudden death, may result from numerous etiologies. Foreign-body aspiration and strangulation are 2 extrinsic causes. Airway obstruction may also be caused by laryngeal edema, asthma, infection, or anaphylaxis. Chronic causes of asphyxia include musculoskeletal diseases (eg, muscular dystrophy, amyotrophic lateral sclerosis), neurologic disorders (eg, myasthenia gravis, multiple sclerosis), respiratory disease (eg, emphysema, chronic bronchitis), or tumors. The manner of death in cases of asphyxiation may be natural, accidental, homicide, or suicide. For the death investigator, determining the cause and manner of death can often be quite challenging. We report here 2 cases of an esophageal fibrovascular polyp causing sudden asphyxial death, review of the literature, and discussion of other differential diagnoses in the case of asphyxial death.

Syphilitic Coronary Artery Ostial Stenosis Resulting in Acute Myocardial Infarction and Death

Cardiovascular abnormalities are well-known manifestations of tertiary syphilis infections. Most notable in this regard is syphilitic aortitis, which tends to result in aortic root dilatation and its associated complications. A less common manifestation of syphilitic aortitis is coronary artery ostial narrowing related to aortic wall thickening. Herein, we present the case of a 32-year-old female who died of a myocardial infarct due to coronary artery ostial stenosis secondary to syphilitic aortitis.

Distribution of organosilicon polymers in augmentation mammaplasties at autopsy.

Silicone-containing breast implants have been used since 1963 for cosmetic augmentation and breast reconstruction. Currently, there is intense debate regarding the extent and mechanism of migration of silicone from the area of implant. The current study compares tissue distribution of organosilicon polymers between women with and without silicone breast implants to determine the extent of silicone migration from breast implants. Samples were collected at autopsy from 15 individuals with bilateral breast implants with no known history of chest trauma and from 14 age- and sex-matched controls. Capsule, breast, axillary lymph nodes, abdominal fat, liver, lung, and spleen were collected for analysis of organosilicon polymers by atomic absorption spectrometry and for examination by light microscopy. Blood was collected for analysis of rheumatoid factor and antinuclear antibodies. Silicone was observed microscopically in at least one capsule section from all implant cases and in at least one lymph node in 8 of 15 implant cases. Silicone was not observed in lymph nodes from control cases. Organosilicon polymers were extracted from tissue using heptane, and the silicon content of the extract was quantitated by atomic absorption spectrometry. Silicon was detected in all capsules; statistically significant increases of organosilicon polymers were measured in axillary lymph nodes, breast, and abdominal fat from individuals with silicone breast implants when compared with the nonimplant group. Measurable amounts of organosilicon polymers were found in tissues from the nonimplant group. Suitable blood specimens were analyzed for the presence of rheumatoid factor and antinuclear antibodies. All nine implant cases tested were negative for the presence of antinuclear antibodies. Three implant cases which were tested for rheumatoid factor also were negative. We conclude that organosilicon polymers routinely migrate from the site of breast implantation to regional tissues near the implant site. Tissues from nonimplant cases often contained measurable amounts of organosilicon polymers, and tissue distribution was variable within any single individual: this is consistent with the wide-spread use and form of organosilicon polymers.

Suicide by drowning: a 20-year review.

Drowning as a method of suicide is known to occur, but has primarily been described in environments with readily available access to water, such as coastal regions. In this study, we describe and analyze a series of suicidal drownings occurring in a noncoastal area of Texas. Between 1977 and 1996, 52 cases of suicidal drowning were investigated at the Southwestern Institute of Forensic Sciences in Dallas, Texas. Such deaths accounted for only 0.85% of all suicides and 4% of all drowning deaths. In contrast. suicidal drownings reportedly account for 2.8 to 8.9% of all suicides in regions with easy access to water. As with other studies of suicidal drowning, the victims are usually sober white males over the age of 40 years. Our results also confirm that certain individuals who commit suicide by drowning use weights to facilitate the process. A detailed analysis of the cases is provided. as is a synopsis of several questions that may aid in determining the manner of death in suicidal drowning cases.

Pregnancy-related maternal deaths

Pregnancy is a normal biologic process, but because of a variety of physiologic factors, it increases a womans risk for death. Maternal deaths in pregnancy may be due to conditions unique to pregnancy, conditions associated with pregnancy, or conditions unrelated to but exacerbated by pregnancy. Death may occur during any trimester, during labor/birth, or postpartum. In this report, we present 45 cases of pregnancy-related maternal deaths that were investigated and autopsied at the Dallas County Medical Examiners office between 1977 and 1999, and we review the topic of pregnancy-related maternal death.