Erik Edston

β-Tryptase measurements post-mortem in anaphylactic deaths and in controls

The reliability of measuring mast cell tryptase in post-mortem blood to diagnose anaphylactic deaths has been questioned because moderate elevation of tryptase can be seen also in control cases. Very high tryptase concentrations have been recorded even in a few control cases with known cause of death such as myocardial infarction or trauma. Aiming to compare findings we measured tryptase in 193 cases: 176 with known cause of death, 10 unexplained deaths and seven anaphylactic or anaphylactoid deaths (AADs). Using binary logistic regression we calculated the sensitivity and specificity of the tryptase test at different cut-off values and found 10 micrograms/l to be optimal, the sensitivity being 86% and the specificity 88%. Traumatic deaths (n = 23), sudden infant death syndrome (n = 40) or deaths after heroin-injection (n = 22) showed elevated tryptase values in 35%, 35% and 32%, respectively, and in 40% of the unexplained deaths (n = 10), which was higher than expected (12%). Heart blood tryptase level was elevated in 22% of the controls and femoral blood tryptase in 10%. No correlations were seen with age or post-mortem delay. It is concluded that tryptase measurements are useful in confirming death from AAD, and that blood should be sampled from the femoral vessels. In unexplained deaths tryptase measurement is a useful indicator, but the diagnosis is not to be based on the test alone.

Anaphylactoid shock – a common cause of death in heroin addicts?

We measured mast‐cell tryptase in postmortem blood from 22 heroin addicts dying suddenly after injection. In 32%, the concentration of tryptase was elevated (≥10 μg/1), and the mean value of tryptase was significantly different from a control group dying from known, nonimmunologic causes (P<0.05). The increased tryptase concentrations indicate that death was preceded by systemic mast‐cell degranulation. All victims of drug deaths had morphine in blood, most below 0.2 μg/ml. In 71% of the victims of drug‐related deaths with tryptase values ≥10 μg/1, the intermediate degradation product, 6–monoacetyl‐morphine, was not found in blood, whereas this was the case in only two victims with values below that cutoff point. This indicates that those with high tryptase concentrations survived longer than those with lower values. No correlation was found between the IgE levels and tryptase in either group, supporting the hypothesis that tryptase release was not mediated by an allergic reaction. The well‐known property of opiates to stimulate unspecifically the liberation of histamine and other constituents of mast‐cell granules offers one explanation of our observations. The results suggest that many heroin fatalities are caused by an anaphylactoid reaction.

Inhaled and intravenous corticosteroids both attenuate chlorine gas-induced lung injury in pigs

Background:  The accidental release of chlorine gas is a constant threat in urban areas. The purpose of this randomized, blinded, controlled experiment was to examine the effects of post‐injury administration of inhaled or intravenous corticosteroid in chlorine gas‐injured pigs followed for 23 h.

The earlobe crease, coronary artery disease, and sudden cardiac death: An autopsy study of 520 individuals

The majority of previous studies have demonstrated a correlation between diagonal earlobe creases (ELC) and coronary artery disease (CAD). In this study of 520 forensic autopsy cases, the earlobes were studied and photographed before autopsy, and the existence of a diagonal ELC was noted in 55%. The cause of death, the degree of coronary atherosclerosis, aortosclerosis, and cerebrosclerosis, as well as heart, kidney, and spleen weights, were noted in each case. The body mass index (BMI), thickness of abdominal fat, baldness, and excessive hair in the meatus externa of the external ears were also assessed. Nonparametric methods were used in the statistical calculations. It was found that ELC was strongly correlated with CAD in both men and women (P < 0.0001) but with sudden cardiac death (SCD) only in men (P < 0.04). The sensitivity of the ELC sign was 75% and the positive predictive value (ppv) was 68%. In individuals below 40 years, the ppv was as high as 80%. Using multiple logistic regression analysis, ELC was found to be the strongest independent risk factor for CAD and SCD apart from age and BMI (both genders), as well as baldness and hair in the meatus externa (in males). It is concluded that in a patient population similar to that in the present study the ELC sign could be especially useful in screening for premature CAD in younger individuals.

TUNEL: a useful screening method in sudden cardiac death.

Abstract The primary objective of this study was to investigate if detection of apoptosis in the heart can be used to diagnose early myocardial ischaemia. The material consisted of myocardial tissue from autopsy cases: 10 cases with occlusive, thrombotic coronary artery disease and acute myocardial infarction, 10 cases of sudden cardiac death without coronary artery disease (CAD) and 8 controls without cardiovascular disease and with known causes of death. Necrotic changes in the myocardium were detected with hematoxylin-erythrosin-saffron, Mallory’s PTAH stain and with antibodies against complement 9. Apoptotic nuclei were visualised with two different kits using the terminal deoxynucleotidyl transferase-mediated desoxyuridinetriphosphate nick end-labeling (TUNEL) method on histological sections. In the patients with CAD, early myocardial infarction was found in one defined area of the ventricular wall; apoptotic myocyte nuclei were observed not in the necrotic lesions, but evenly spread usually without a gradient, all over the myocardium with a mean number per high power field of 29% (range 3–56%) of the total number of myocyte nuclei. In the sudden cardiac deaths without CAD, necrosis was scarce and distributed both focally and irregularly in both the left and right ventricular walls. With few exceptions, the percentage of apoptotic myocyte nuclei exceeded 20% in all sections (mean 24%, range 0–68%). No difference was seen between patients with CAD and those without CAD (p > 0.05). With the TUNEL method, positively stained nuclei were seen very early and extensively all over the myocardium. It is not certain that they represent true apoptosis induced by ischemia, but TUNEL appears to be a useful screening method in cases where sudden cardiac death is suspected.

Increased mast cell tryptase in sudden infant death : anaphylaxis, hypoxia or artefact?

Increased concentrations of mast cell tryptase in post mortem blood have frequently been observed in sudden infant deaths but the cause of this has not yet been clarified.

Mast cell tryptase and hemolysis after trauma

BACKGROUND We have previously found increased mast cell tryptase in accidental deaths due to trauma, indicating that mast cell degranulation had occurred. The present study was designed to confirm the previous observation and to determine if tryptase release after trauma is acute or delayed. Furthermore, the importance of hemolysis and direct trauma to the mast cells was investigated. MATERIALS AND METHODS Mast cell tryptase was measured in post-mortem blood from the femoral vein in 27 cases of death from trauma and in 27 control cases by means of a commercially available immunoassay. The trauma cases were further classified into groups with single versus multiple trauma, and groups with short survival time (i.e. death at the scene of the accident) versus longer survival time (death in hospital). In five multi-trauma deaths, blood was sampled locally from the sites of crush injury. RESULTS The mean value of tryptase in femoral vein blood was 35.6+/-34.6 microg/l in the entire trauma group and 14.7+/-6.5 microg/l in the controls (P<0.005). In bloody liquid sampled from crush injuries, tryptase was substantially elevated in all cases, with a mean of 227+/-146 microg/l. In cases with short survival time, tryptase was significantly higher than in those who died after several hours or days in hospital (P<0.001). No statistically significant difference was seen between multi- and single-trauma cases. A correlation between hemolysis in the samples and elevated tryptase was found only in the trauma cases (P<0.05), but experimentally induced hemolysis in vitro was not found to influence the measurements. CONCLUSION Mast cell tryptase becomes elevated in trauma deaths and this seems to be ascribable either to direct mechanical injury to tissue mast cells and/or to cell lysis. In patients initially surviving severe injuries, the effects of massive release of histamine and other mast cell mediators might be of importance for treatment strategies and prognosis.

Postmortem measurements of thyroid hormones in blood and vitreous humor combined with histology.

The aim of this study was to investigate whether clinical reference premortem values can be used to assess postmortem concentrations of thyroxine, triiodothyronine, and thyroid stimulating hormone (TSH), to compare the postmortem concentrations in blood and vitreous humor, and to study the possibility of diagnosing hyperthyroidism by comparing thyroid histologic appearance and postmortem hormone values. Biochemical analyses of free thyroxine (FT4), free triiodothyronine (FT3), and TSH in femoral blood and vitreous humor were made in 38 cases. In 40 cases, the hormones and thyroid histologic appearance were studied; 22 had no significant pathologic changes, and 18 showed focal hyperplasia of the follicular epithelium. A positive correlation was seen between the femoral blood and vitreous humor concentrations of FT4 (R = 0.66) but not between the corresponding concentrations of FT3 and TSH. A positive correlation was also seen between FT3 and FT4 in femoral blood (R = 0.74). In cases with normal thyroid histologic appearance, 58% were found to have FT4 values >24 pmol/L (clinical reference interval 9–24 pmol/L), mean value 27.5 ± 9.4 pmol/L), which did not differ from the FT4 values in the cases with hyperplasia, 31.6 ± 15 pmol/L. Only 5% of the T3 measurements in the group with normal histologic appearance were >9 pmol/L (clinical reference interval 3–9 pmol/L). The mean value of FT3 in cases with normal histologic appearance was 3.4 ± 1.3 pmol/L, and in the group with hyperplasia 8.6 ± 6.1 pmol/L. The difference was statistically significant P < .005). It is concluded that postmortem values of FT3 and FT4 in femoral blood are fairly comparable to premortem clinical reference values, but the upper normal limit, especially for T4, has to be adjusted upward. Analysis of vitreous humor cannot be used post mortem to assess thyroid function. Histologically, hyperplastic changes correlate well with elevated FT3 in femoral blood.

Immunoglobulin E, mast cell-specific tryptase and the complement system in sudden death from coronary artery thrombosis

We tested the hypothesis of anaphylaxis as a pathogenic factor in acute myocardial infarction. Mast cells were counted in the myocardium, coronary arteries and airways. Total serum IgE, mast cell tryptase, complements C3, C4, and factor B, were measured in 29 cases of sudden death from coronary artery thrombosis and in 27 controls. We found increased numbers of mast cells in the coronary arteries following coronary death: 46 +/- 21 (SD) compared with 22 +/- 10 (SD) in the control group (P < 0.002). In the myocardium and airways there were no differences between the groups. The concentrations of tryptase and IgE in serum did not differ between the groups although 20% of the coronary deaths had elevated values (> 200 kU/l) compared with 8% in the control group. Of the complement factors, C3 was higher in the coronary deaths (P < 0.05) than in the controls. The results give no evidence of anaphylactic reaction in the pathogenesis of acute myocardial infarction.

Histiocytoid cardiomyopathy and ventricular non-compaction in a case of sudden death in a female infant

A case of sudden infant death with histiocytoid cardiomyopathy and ventricular non-compaction was investigated with immunohistochemical methods. Histiocytoid cardiomyopathy is thought to be a developmental defect of the cardiomyocytes of the conduction system. In contrast to mature cardiomyocytes, the histiocytoid cells showed only weak reactions to desmin and myosin antibodies. They lacked cross-striation but reacted strongly to enolase and myoglobin antibodies. The protein Pax-7, seen only in cells undergoing differentiation, and the proliferation marker Ki-67 were not expressed in the histiocytoid cells. In areas of altered myocardium, clusters of CD4-, CD8-, and CD68-positive inflammatory cells were seen as well an abundance of mast cells. With the TUNEL method, it was found that many of the histiocytoid cells were undergoing apoptosis. Our results confirm that the histiocytoid cells are defective cardiomyocytes. The apoptotic and inflammatory changes point to a degenerative process rather than defective maturation of cardiomyocytes as has been suggested in some earlier studies. Ventricular non-compaction is a developmental defect of the subendocardial tissue with hypertrabeculation and weak development of the papillary muscles. Only one case combined with histiocytoid cardiomyopathy has been described previously. A causal connection between the two conditions cannot be established until more cases have been analyzed.