Postmortem Clinical Chemistries

POSTMORTEM CLINICAL CHEMISTRIES

11

Postmortem biochemical studies may be conducted along with the more common toxicological testing in conjunction with the autopsy. These studies in many cases are crucial for the determination of the cause and manner of death. Postmortem chemistries may be useful in a variety of cases; demonstrating a biochemical abnormality that is responsible for the death [1], assist in the evaluation of the physiological effects of recognized pathology [2] and some authors claim it may assist in the determination of the time of death [3]. Chemical composition of vitreous fluid is more stable than blood or cerebral spinal fluid (CSF) [4]. Although, as discussed later in this chapter, there are some clinical chemistry studies that may be conducted on synovial fluid, CSF, or blood samples.

Vitreous Fluid The most common biochemical studies are carried out on vitreous fluid from the eye, these studies are also referred to as postmortem vitreous chemical studies or vitreous (bio)chemical studies. Vitreous fluid is ideal for postmortem chemical analyses; it is isolated from the blood and other fluids and tissues that may be subject to postmortem changes, such as postmortem redistribution and hemoconcentration. It resists putrefactive changes, although it is not totally immune from them. The eye is isolated and well-protected anatomically, thus the vitreous is usually well preserved despite serious trauma to the head and is less subject to external contamination. The vitreous fluid in the globe of the eye, between the retina and lens, is an acellular, viscous (2 4 times that of water), and colorless fluid. It is composed of predominately water (B99%) with very small amounts of glucose, except in hyperglycemic patients, hyaluronic acid, collagen fibers, inorganic Postmortem Toxicology. DOI: https://doi.org/10.1016/B978-0-12-815163-1.00011-3 © 2019 Elsevier Inc. All rights reserved.

147

148

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

salts and ascorbic acid. Due to its high water content low molecular weight compounds, such as ethyl alcohol, that are not protein bound and electrolytes will equilibrate with the vitreous, thus making it a suitable matrix for the analyses of these analytes. The measured vitreous electrolyte concentrations are relatively stable and will reflect the antemortem serum concentrations of sodium, chloride, and urea nitrogen. The chemical composition of these electrolytes was more stable in vitreous as compared to postmortem blood or CSF [4]. Coe [5] provides a review of the literature examining the utility of vitreous chemistry studies for a variety of analytes. He found that the determination of vitreous urea nitrogen, glucose, and electrolytes found in individuals dying of “natural diseases” yield significant results in over 5% of the cases evaluated. There are three major factors one should consider in the evaluation of postmortem vitreous biochemical studies; (1) sample time, (2) sample source and acquisition technique, and (3) analytical methodology employed in the analyses. The vitreous samples should be obtained during the early postmortem interval. In an adult, 2 3 mL of fluid may be obtained from each eye, with an infant up to 1 mL of fluid is available. As the postmortem interval increase, the vitreous fluid will change in character from a relatively clear colorless viscous fluid to a cloudy brownish-colored fluid. The vitreous sample should be aspirated from the lateral aspect of the eye, with gradual and gentle suction; strong suction should be avoided in the collection process. An initial strong suction may cause fragments of the retina or internal tissue of the globe of the eye to contaminate the specimen. It is recommended that vitreous from one eye be placed in a redtop tube for electrolyte analyses and a sample in a gray-top tube for glucose determinations; other analytes except sodium may be tested from this sample as well. There are insignificant differences between concentrations of electrolytes between eyes [6,7]. Since the fluid is viscous and many techniques utilize a small sample that is aspirated into the instrument, a technique to reduce the viscosity of the sample is desirable. These may include centrifugation [7], the addition of hyaluronidase [8], or heating the sample at 110 C for 5 minutes [9]. Coe and Apple [10] studied glucose, urea nitrogen, sodium, potassium, and chloride on a variety of instrumental platforms. They found variations in values obtained by the

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

different procedure/instruments. However, the variations were not significant enough to cause interpretive problems for glucose and urea nitrogen, although they did impact the other electrolytes.

Glucose Blood glucose concentration will increase in the agonal stages of life; related to the terminal stress place on the body, leading to increased secretions of catecholamines and subsequent glycogenolysis, conversion of glycogen to glucose. Significant increases in blood glucose may be seen in asphyxial deaths, cerebral hemorrhage, congestive heart failure, electrocutions, and cases with cardiopulmonary resuscitation. Coe [11] examined 1000 consecutive natural deaths and found that 103 nondiabetic cases had peripheral blood glucose values greater than 500 mg/dL; of note 87 of these cases received cardiopulmonary resuscitation. Thus making the diagnosis of antemortem hyperglycemia essentially impossible from a blood measurement; however, elevated vitreous glucose concentration may indicate a hyperglycemic state prior to death. In Coe [11] study of postmortem blood glucose concentrations, he noted that in the non-diabetic cases with blood glucose concentrations greater than 500 mg/dL, the vitreous glucose concentration was never greater than 100 mg/dL. Coe [12] also examined more than 6000 vitreous samples for glucose and found concentrations did not exceed 200 mg/dL in nondiabetic decedents. The author felt that a diagnosis of diabetic ketoacidosis could be made from vitreous glucose concentrations exceeding 200 mg/dL, along with elevated concentrations of ketones. Although the diagnosis of hyperglycemia may be made from elevated vitreous glucose concentrations, a low value is not indicative of hypoglycemia, the sugar levels may simply be reduced by glycolytic enzymes. Sturner et al. [13] measured vitreous glucose in nonhypoglycemic children and in many cases found vitreous glucose concentration of less than 100 mg/dL. Hypothermia frequently will cause hyperglycemia in patients. Coe [14] found that 80% of a group of patients treated for hypothermia had elevated blood glucose concentrations. Vitreous glucose concentrations in hypothermic deaths (n 5 26) ranged from 18 to 170 mg/dL, with a mean value of 82.6 mg/dL. The two control groups (n 5 100; routine cases dying at ambient

149

150

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

temperature and n 5 27 acute trauma cases dying outdoors during the winter) had mean vitreous glucose concentrations of 37 mg/dL. An elevated vitreous glucose values may provide supportive evidence for hypothermia deaths.

Nitrogen Compounds Urea nitrogen is the most stable of all the commonly measured vitreous analytes [15]. Coe [4] found that in more than 90% of cases studied, there was less than 3 mg/dL variation in concentration (normal range: 10 20 mg/dL) urea nitrogen in the vitreous samples. It has value in assessing renal function, with uremia being easily identified and determination of mild nitrogen retention in association with hypernatremia can be used to verify antemortem dehydration.

Creatinine Creatinine is equally as valid as urea nitrogen for the determination of nitrogen retention. Studies have shown that vitreous humor creatinine concentrations are slightly lower than antemortem serum concentrations [16]. Leahy and Farber [15] evaluated 29 patients with serum creatinine concentrations of less than 1.5 mg% and in which vitreous was collected within 24 hours of death and found vitreous creatinine concentration ranging from 0.31 to 1.05 mg%. There were no patients with normal antemortem serum creatinine concentrations that had an elevated postmortem vitreous creatinine concentration. In 8 of the 29 patients, where the antemortem serum concentration of creatinine exceeded 1.5 mg%, all postmortem vitreous creatinine concentrations were greater than 1.1 mg%.

Sodium Vitreous sodium concentrations are relatively stable during the early postmortem interval. The concentrations for individuals are similar to those found in serum samples; normal range being 140 145 mEq/L. Coe [4] and Swift et al. [17], and others have found that all individuals with abnormal vitreous sodium concentrations had corresponding antemortem hypoor hypernatremia. There are a number of reasons [18] for a patient to present with hypernatremia, some of which are listed in Table 11.1. Salt or water intoxication, as discussed below, may lead to hyper- or hyponatremia, respectively [19]; along with a unique syndrome called “Beer Potomania.” This syndrome is associated which excessive beer drinking resulting in hyponatremia [20,21].

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

151

Table 11.1 Causes of Hypernatremia or Hypertonic Sodium Gain Hypernatremia Hypertonic NaHCO3 infusion Hypertonic feeding preparations Ingestion of NaCl Ingestion of Sea water Hypertonic saline enemas

Intrauterine injection of hypertonic saline Hypertonic saline IV infusion Hypertonic dialysis Primary hyperaldosteronism Cushing’s disease

Chloride In vitreous humor, chloride is similar to sodium, with concentrations showing only a minimal decline in concentration during the early postmortem interval [4,16]. A number of investigators, along with Coe [4] and Naumann [16] have established the normal range for vitreous chloride to be 115 125 mEq/L, with infants being slightly lower. As with sodium, abnormalities in antemortem serum chloride are reflected in the postmortem vitreous concentrations. Therefore, allowing for the identification of electrolyte imbalances while the patient was alive.

Potassium Potassium begins to leave the cells of the body rapidly after death. As the cells lyse, the “serum” potassium concentrations rise rapidly, thus making it impossible to assess the status of the perimortem concentrations. In general, the vitreous potassium concentrations gradually rise in a somewhat linear fashion following death. Because of this, numerous investigators have studied the relationship between vitreous potassium concentrations and the postmortem interval with varying results. There are numerous factors that influence the rate of rise of vitreous potassium concentrations. Coe [22] and Madea [23] provide reviews of the use of potassium concentrations for the determination of the postmortem interval and factors influencing the rate of rise in concentration, thus impacting the time interval estimate. The most significant external factor is temperature of the environment, and hence the body temperature during the postmortem interval. Blumenfeld et al. [24] observed that the rate of rise of potassium was faster in an

152

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

infant as compared to the adult in similar environments; there was a positive correlation of vitreous potassium concentration with the postmortem interval, however the variation of 1 26 hours made the estimation of the time of death unpractical. Sparks et al. [25] found that potassium concentrations were more erratic in patients dying from chronic illness compared to those dying from acute traumatic deaths. They also noted that the increases in potassium concentrations were steeper in the rate of rise in patients with significant urea nitrogen retention. Ortmann et al. [3] evaluated five different equations that have been described to estimate the time since death. The authors describe some of the many factors that influence the rate of rise in vitreous potassium over the postmortem interval; ambient temperature, duration of the terminal episode, composition of the sampled population (hospital deaths and/or medical examiner cases), sampling method, and instrumentation used to measure the potassium concentration, and age (body mass). They found that the formulas using slopes of 0.17 or 0.19 mmol/L per hour gave the best results; from about 20 to 100 hours since death. Vaitla and Vani [26] reported the rate of rise of potassium to be 3.32 mEq/L per hour and used to estimate time since death in the range of less than 12 hours up to 48 hours. In this time frame, the authors state that factors such as age, sex, cause of death, along with environmental factors of humidity and temperature did not impact the concentration of potassium. Although, Zilg et al. [27] found that the rise in potassium concentration was nonlinear and influenced greatly by age of the decedent and ambient temperature that the body was exposed to. Recently, Li et al. [28] suggest a multiconstituent analysis of various vitreous analytes; inorganic ions including potassium, amino acids, glucose, and protein may be helpful in estimating the postmortem interval. However, due to factors listed above and other confound challenges; many have abandoned the use of vitreous potassium concentrations for the determination of the postmortem interval. Potassium chloride has also been used in suicides and judicial executions. Bertol et al. [29] report on a 41-year-old male who committed suicide by injection of potassium chloride. Normal plasma concentrations for potassium range from 3.5 to 5.0 mEq/L (mM). The potassium concentration, by ion selective electrode analysis, in the decedent was determined to be 160.0 mM in heart blood and 87.3 mM in femoral blood; with the only other positive finding of diazepam at 0.21 mg/L and

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

nordiazepam was reported as positive. To determine the “postmortem normal” potassium concentration, the authors tested 55 autopsy femoral blood samples from cases with no toxicological involvement. They found potassium concentrations ranging from 27.2 to 50.1 mM (mean: 36.2 and median: 35.3 mM). A vitreous sample was not collected. The authors concluded from this isolated case study that potassium was significantly higher in heart blood in this suicide case. Palmiere et al. [30] measured potassium concertation in left and right vitreous, postmortem serum from cardiac and peripheral blood samples, heart blood, urine, pericardial fluid, and CSF in 21 autopsy cases; one of which was a fatal inadvertent administration of potassium chloride in a hospitalized patient. The authors found no statistically significant differences in the measured potassium concentrations in the fatal overdose as compared to the 20 “control cases.” In a case of a judicial execution, where potassium chloride was the final drug administered to the inmate, the vitreous potassium concentration was not outside of the concentration range normally seen in other autopsy cases (Rohrig personal communication). Electrolyte abnormalities generally tend to fall into four common patterns; dehydration pattern (hypertonic pattern), uremic pattern, low-salt pattern (hypotonic pattern), and a decompositional pattern. A dehydration pattern is characterized by a concomitant rise in sodium and chloride concentrations in the vitreous, along with a moderate elevation of urea nitrogen. A uremic pattern differs from a dehydration pattern in that the vitreous urea nitrogen and creatinine concentrations increase to an appreciable extend, without increases in sodium or chloride. A low salt pattern or hypotonic pattern is characterized by low sodium and chloride concentration in the vitreous and a low potassium concentration, less than 15 mEq/L. Whereas, a decompositional pattern is like a low salt pattern; that is, low sodium and chloride, but it has a high potassium concentration, generally exceeding 20 mEq/L. Although potassium concentrations are not necessarily useful in the determination of the postmortem interval, it is important for the differentiation of these two latter patterns.

Exogenous Intoxications In addition to detecting biochemical anomalies, vitreous electrolyte analyses can detect various types of exogenous poisonings.

153

154

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

Salt (sodium chloride) is rapidly absorbed and distributed throughout the body before renal excretion can occur; therefore a small amount of salt may have a potential lethal outcome. This is especially a concern in pediatric cases, in that their immature kidneys have a decreased ability to excrete excess sodium [31]. Nine grams of salt (approximately two teaspoons) will increase serum sodium concentration by 10 meq/L in an adult [32]. Excess sodium will cause a hyperosmolar effect; causing a movement of water from intracellular spaces to extracellular spaces resulting in intracellular dehydration, vascular overload, and brain shrinkage, with tearing of the cerebral vessels and subsequently intracerebral hemorrhage; resulting in death as quickly as a few hours post ingestion [33]. Hypernatremia induced cerebral hemorrhages have a mortality rate of 40% 70% [34]. Meadow [31] describes a calculation; based upon infant weight and serum sodium concentration, in which the quantity of salt ingested to cause a specific level of hypernatremia, may be determined. The author goes on to state that if gastric aspirates contain over 200 mmol/L of sodium (normal 50 60 mmol/L), an exogenous source may be suspected. Although rare in occurrence, accidental salt poisoning has been reported both in children and adults. In a pediatric population, small amounts of salt may lead to profound hypernatremia resulting in death. Finberg et al. [35] reported on the hospital deaths of six infants who were given formulas that were prepared with salt instead of sugar. The patients exhibit hypernatremia, followed by seizures and ultimately dying. Death in the adult population has also occurred from salt intoxication. Ingestion of salt from the accidental ingestion of a supersaturated solution of salt water meant for gargling resulted in the death of a 41-year-old male [36]. The decedent ingested approximately 70 90 g of sodium chloride, and presented with an initial serum sodium concentration of 209 mEg/L. He was aggressively treated with hypotonic fluids and support therapy, however, died 3 days later. Salting of an infant’s skin in the early neonatal period is an old Turkish custom, originating in Middle Asia [37,38]. Salting of the infant’s skin is performed to increasing the probability that the baby will be healthy [39]. In a study sampling 121 Turkish women, 70% of the interviewed women had heard that bathing an infant in salt water would prevent it from developing an offensive odor and 40% of the women had actually performed this custom [40].

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

Rehm [41] describes a case where the parents fed a commercial can of chicken soap to their child; resulting in hypernatremia. Many of these soaps are sold in concentrated form with instructions to dilute two- to threefold; thus avoiding the ingestion of a hypertonic solution. Therapeutic intervention with salt solutions may lead to toxicity, including death. Kaufman et al. [42] reports on a child who presented to the Burn Unit 3 hours after receiving scald burns on about 25% of her body. The parents attempted to treat these injuries by covering the burns with sodium chloride. The child presented comatose, tachypnoeic (respiratory rate 60/min), rapid pulse (160/min), and low blood pressure (60/0 mmHg). Her initial serum sodium and chloride levels were 200 and 136 mmol/L, respectively. The burn areas were irrigated with aggressive medical interventions; however the child about 1.5 hours later. Accidental ingestion of medications in children has been treated either with gastric lavage or emetics to induce vomiting, to aid in the removal of the drug. Carter and Fotheringham [43] describe a death of a 2-year-old due to a gastric lavage with a hypertonic salt solution. Smith and Palevsky [33] describe a case of a 2-year-old that was given an emetic solution by her babysitter after an accidental ingestion of nortriptyline. The child became nauseated and unresponsive over the next few hours and was subsequently transported to the hospital. The child exhibited grand mal seizures and had a urinary output of 750 mL over a 2-hour period. Laboratory analyses showed elevated serum sodium and chloride levels (202 and 206 meq/L, respectively), along with a toxic concentration of nortriptyline (234 ng/mL). Cardiac arrest ensued and resuscitative measures were unsuccessful. Salt poisoning may be part of a Munchausen syndrome by proxy or an attempt to cover up child abuse cases. Munchausen by proxy is a syndrome where an individual fakes or induces an illness on another for the purpose of gaining attention to him/herself. Lacey Spears craved attention received through her 5-year-old son. She detailed his “mysterious” illness, including ear infections, seizure-like symptoms, and digestive issues, for years on her blog “Garnett’s Journey” [44]. She also took to various social media outlets to share updates on her son’s health condition, writing about his health struggles up to the time of his death in 2014. Evidence indicated Spears had taken her son to 20 different medical facilities over his life claiming none could figure out what was the cause of his maladies. Subsequent investigation

155

156

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

determined that Spears was introducing salt via her son’s feeding tube to induce illness. In 2015, Spears was found guilty of murder and sentenced to 20 years to life. Feldman and Robertson [45] describe two cases of young children (2.5- and 3-year-old) who presented with severe hypernatremia. The children apparently had been administered salt and deprived the children of water as a form of child abuse. Salt poising has also been use as a form of punishment. Baugh et al. [46] report a case of salt poisoning as a result of punishment for enuresis. A 5-year-old boy presented to the hospital following a reported 3-hour history of diarrhea and facial pallor. He had been reported to have been well until 12 hours earlier when “loose” stools began, which worsened rapidly, with profuse diarrhea, urinary incontinence, pallor, and lethargy. Physical examination revealed sunken eyes, oral mucosa moist, however, lips were dry and cardiac dysrhythmias. The presumptive diagnosis was dehydration, with treatment of normal saline solution, which resulted in a production of 200 mL of urine. Laboratory studies showed elevated levels of sodium and chloride (184 and 143 meq/L, respectively). After commencement of treatment there was an abrupt decline of in serum sodium, with significant improve of neurological status; lethargy disappeared a resolution of cardiac arrhythmias. A 4 month follow-up revealed no lasting sequelae. Upon interview of the parent, they admitted to giving the child salt as a punishment for his bedwetting. The ingestion of sodium hypochlorite (bleach) may also result in fatal hypernatremia and hypochloremia. Ross and Spiller [47] report a case of fatal ingestion of a bleach solution in a 66-year-old woman. She ingested an unknown amount of a regular commercial bleach solution (5.25%). Upon discovery she was noted to be vomiting, with oral mucosal discoloration and slurred speech. At the hospital, she became unresponsive with shallow respirations. Laboratory studies reveal hypernatremia and hypochloremia (169 and 143 meq/L, respectively). There was a rapid clinical decline, with cardiac arrest, leading to death. Hilbert et al. [48] describe the suicide of a 32-year-old woman who ingested 750 mL of a concentrated bleach solution (13.3% sodium hypochlorite) and 24 mg of flunitrazepam. She presented with a coma, difficulty breathing, vomiting, and a slightly elevated blood pressure and pulse. Initial sodium level was 195 meq/L, and 12 hours post ingestion remained high at 195 meq/L, another measurement was made at 24 hours post ingestion with a result of 162 meq/L.

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

She ultimately died 65 hours after ingestion, as a result of multiorgan failure, refractory hypoxemia, and disseminated intravascular coagulation. Water intoxication is an infrequently encountered condition that is due to the overconsumption of water which may have a lethal outcome. The initial symptoms or observations of water intoxication is polydipsia (increased consumption of water) and with frequent urination of dilute urine (polyuria). Other signs and symptoms may include headache, nausea/vomiting, behavioral changes, muscle weakness, twitching and cramping, sensory disorders, confusion, irritability, and drowsiness [49]. Excessive water consumption is generally compensated by higher diuresis. Healthy adult kidneys will generally remove about 15 L/day of water. When the capacity is exceeded, it will result in hypotonic hyperhydration; which mainly has an adverse effect on the brain, leading to brain edema and tissue damage. There are three main etiologic sources for water intoxication; psychiatric (polydipsic-hyponatremic-schizophenia and anorexia nervosa), child abuse, and drug abuse. Helwig et al. [50] reported one of the first cases of fatal water intoxication. Their patient presented with significant hyponatremia, agitation, convulsions, and coma and finally expired; he had ingested 9 L of tap water through rectal administration. Chertow and Brady [51] describe a quadriplegic patient who was receiving tap water enemas; five “treatments” over a 10-day period. During the course of his fifth treatment, he became confused and had tonic clonic seizures. Laboratory studies showed serum sodium concentrations ranging between 89 and 93 mmol/L. He was treated with hypertonic saline, and although the seizures resolved he remained in a coma and subsequently died. Raskind [52] reports on a 56-year-old woman, with a longstanding psychiatric diagnosis, who consumed copious amounts of water during an acute psychiatric episode. She was also being treated with thioridazine and hydroflumethiazide, both which have antidiuretic hormone activity. Their patient was described as having increased symptoms of agitation, confusion, fearfulness, head discomfort, weakness, nausea, polyuria, and abdominal fullness. She subsequently was found to be unresponsive and exhibited a neurogenic hyperventilation, decerebrate posturing, and apnea; her clinical course declined and subsequently died a few days later. Postmortem examination revealed a transtentorial herniation due to a generalized cerebral edema. Rendell et al. [53] describes two patients who

157

158

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

die from water intoxication in a similar manner as to Raskind’s patient, however, in the absence of treatment with any pharmacological agents that would affect water homeostasis. Radojevic et al. [49] reports on four cases of water intoxication. One case, a 5-year-old boy was admitted to the hospital for strong thirst and excessive water intake of approximately 6 L per day, over a 10-day period. Parental history describes a “stressogenic” situation in which previously the family’s water system failed and the young boy was reported to be very thirsty for 1.5 hours. The recent stressor was the birth of a brother, and a psychological evaluation suggested that this new stressor evoked the previous stressogenic situation, resulting in excessive water consumption. The second case was one of suspected child abuse. A 6-year-old boy was playing outside on a hot summer afternoon and was continuing interrupting his mother for a glass of water. The mother became irritated and placed a garden hose in the child’s mouth and turned on the water while holding his head to the hose. A bystander observed this behavior and law enforcement was contacted. Upon arrival, the boy was found unconscious, with foam coming from his mouth and nares. At the hospital, 1900 mL of water was removed from the stomach, and laboratory studied indicated a mild hypotonic hyperhydration. The boy recovered without permanent brain damage. The third case involved a schizophrenic man who had a history of compulsive water consumption. He was found dead next to a sink with running water. Autopsy showed generalized congestion, brain edema, and about 1000 mL of urine in his bladder. Vitreous biochemical studies reveal a sodium concentration of 112 mmol/L. The fourth case also involved a schizophrenic patient with a history of excessive water intake. The patient was admitted to the hospital with an alteration of consciousness, and urination without control. Laboratory studies reveal a hyponatremic state (98 mmol/L), in spite of aggressive therapeutic intervention the patient expired 4 days post hospital admission. The last two cases have also been referred to as patients with polydipsic-hyponatremic-schizophrenia. Arieff and Kronlund [54] describe three cases of child abuse where water was used to punish the children. All three children were forced to drink large amounts of water ( . 6 L) over a short period of time. They also exhibited signs of physical abuse. They presented to the hospital with seizure activity, emesis, and coma and were hyponatremic (112 mmol/L). At autopsy, the decedents had cerebral edema and aspiration pneumonia.

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

Drug abusers have been known to die from water intoxication due to the hyperthermic and anticholinergic effects (dry mouth) of the drugs. Milroy et al. [55] described a case of water intoxication from methylenedioxymethamphetamine abuse, which resulted in death. The decedent was found in bed hyperthermic (39.5 C) and was reported to have ingested 14 L of water.

Ethyl Alcohol Ethyl alcohol determinations are routinely performed on vitreous samples. The interpretive value of the results aid in the evaluation of whether or not the decedent was in the absorptive phase or postabsorptive phase of alcohol kinetics, and it is used to help differentiate between the antemortem ingestion of alcohol versus the neoformation of alcohol after death (discussed in detail in Chapter 12: Postmortem Formation of Alcohol and Other Compounds).

Synovial Fluid Another body fluid useful for biochemical studies, although less investigated, is synovial fluid. A synovial joint, also known as diarthrosis, joins bones with a fibrous capsule that is continuous with the periosteum of the joined bones; it constitutes the outer boundary of the joint, and surrounds the bones’ articulating surfaces and an inner layer, the synovial membrane, which seals in the synovial fluid. The synovial fluid is a viscous fluid containing mainly water and like vitreous it contains hyaluronic acid. The joint most often sampled for forensic purposed is the knee joint, the amount of fluid is variable ranging from 0.5 to 3.0 mL in adults [56]. Normal synovial fluid is clear, pale yellow, viscid, and does not clot. Synovial fluid is a plasma dialysate modified by constituents secreted by the joint tissues. The major difference between synovial fluid and other body fluids derived from plasma is the high content of hyaluronic acid (mucin) in synovial fluid. The normal viscosity of synovial fluid is due to the hyaluronic acid. Synovial fluid is believed to have two main functions: to aid in the nutrition of articular cartilage by acting as a transport medium for nutritional substances, such as glucose, and to aid in the mechanical function of joints by lubrication of the articulating surfaces. Articular cartilage has no blood, nerve, or

159

160

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

lymphatic supply. Glucose for articular cartilage chondrocyte energy is transported from the periarticular vasculature to the cartilage by the synovial fluid. Ethyl alcohol determinations have been made utilizing this sample type. Winek et al. [57] evaluated 28 alcohol positive cases, in which they compared blood alcohol concentrations to the synovial fluid alcohol concentrations. They found the blood to synovial fluid ratio was 0.99 and a correlation ¨ et al. [58]. conducted a similar study coefficient of 0.89. Bu¨yu evaluating 50 autopsy cases with 35 case having no ethyl alcohol detected in either fluid; that is, no false-positive results. The remaining cases were positive for alcohol, 2 of them were positive for methyl alcohol and the remaining 13 were positive for ethyl alcohol. In the 15 positive cases, only in one case was the alcohol concentration lower in the synovial fluid than that determined in the blood. In the 13 ethyl alcohol positive cases, the mean blood to synovial fluid ratio of 0.95 and with a correlation coefficient of 0.984. These studies demonstrate that synovial fluid is a viable option for alcohol analyses especially when blood or vitreous is not available. Madea et al. [59] conducted a preliminary study examining 74 cases of sudden death; comparing sodium, potassium, calcium, chloride, urea, creatinine, and glucose in vitreous and knee synovial fluid. The authors noted that the analysis of synovial fluid was a little more difficult due to the fact that synovial fluid was more viscous than the vitreous fluid. They found that the sodium mean concentration was the same in vitreous fluid as in synovial fluid, whereas the mean chloride concentration of the vitreous was higher than the synovial fluid. The mean calcium concentration was higher in synovial fluid as compared to the vitreous, similar to the creatinine mean concentrations; however, the creatinine concentrations demonstrated a wide variability in results. Although the mean concentrations of urea were similar in both the vitreous and synovial fluid, this analyte showed the greatest variability of all. During the early postmortem interval, synovial glucose was higher than the vitreous but both declined to zero with an increasing postmortem interval. The potassium concentrations were significantly higher in the vitreous as compared to the synovial fluid, and concentrations rose in both with an increasing postmortem interval. The authors caution as to the use of synovial fluid biochemistry results in diagnosing acute biochemical abnormalities. Tumram et al. [60] evaluated these biochemical markers on 154 autopsy cases where the time of death was known; and like Madea et al. [59] compared vitreous

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

humor and synovial fluid results. They found both fluids were comparable, and again caution the utilization of the results as with vitreous.

Cerebrospinal Fluid CSF is another useful specimen for the determination of alcohol, glucose, and other biochemical markers. Backer et al. [61] compared alcohol concentrations in CFS and postmortem blood. The authors found the ratio in the elimination phase approximately 1.1. Naumann [62] examined postmortem CSF and peripheral blood; finding that CSF was a more reliable indicator of hyperglycemia than the blood. The author opined that in nondiabetics the CSF glucose concentration would remain below 200 mg%. CSF glucose concentrations greater than 200 mg%, especially in combination with a positive acetone was indicative of uncontrolled diabetes. Fekete and Kerenyi [63] opined that CSF concentrations over 150 200 mg% denoted antemortem hyperglycemia. The author did note that hypoglycemia could not be diagnosed from a CSF measure and further caution that glucose concentrations in the CSF fall rapidly, even in cases of antemortem hyperglycemia. Therefore, a value below 150 200 mg% does not necessarily rule out an antemortem hyperglycemic state. Naumann [62] also compared concentrations of sodium and chloride in CSF in 131 cases shortly after death and found that the mean values were lower as compared to normal antemortem values; sodium 127 versus 142 meq/L and chloride 113 versus 125 meq/L.

Blood Blood, serum or plasma are useful matrices in clinical medicine for the evaluation of various biochemical markers to help diagnosis disease. However in postmortem samples, due to varying decomposition of the matrix and/or targeted analyte is in many cases has limited value. As discussed previously, some of these biochemical markers may be tested for in vitreous humor, synovial, and/or CSF. However, there are some analytes that postmortem blood may still provide valuable information which may aid in the determination of the cause of death. Blood ketones, creatinine, hemoglobin A1C, methemoglobin (metHb), and typtase have all been measured in postmortem

161

162

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

blood samples for the potential to aid in the identification of certain physiological disorders and/or exposure to certain toxins.

Ketoacidosis The analysis of various volatile compounds, including acetone, in postmortem blood is commonly performed. The presence of acetone is often associated with excess alcohol use (alcoholic ketoacidosis), starvation diets/malnutrition and diabetes (diabetic ketoacidosis). Alcoholic acidosis presents with significantly elevated acetone concentration, along with other ketone bodies. It is caused by the generally poor diet of alcoholics, who have a recent history of an alcoholic binge [64]. A typical case presentation is described by McMahon et al. [65]. A 43-year-old alcoholic is admitted to the hospital in a coma, following 3 days of nausea and generalized malaise. Upon recovery, after supportive treatment including intravenous dextrose, the patient reported that the event had been preceded by a 3-week drinking binge coupled with a poor diet. Ketoacidosis may also be induced by ketogenic diets which comprise high fat and low carbohydrate diets or very low carbohydrate diets, which are sometimes referred to as nutritional ketosis [66]. Starvation ketosis is associated with malnutrition, independent of chronic alcohol abuse [67]. The acetone/ketone body levels are generally lower than what is seen with alcoholic or diabetic ketosis. Starvation ketoacidosis may also be attributed to pregnancy [68] or perioperative diets [69], for example, low calorie, protein-sparing diets for a brief period prior to bariatric surgery [70]. Diabetic ketoacidosis is seen in a number of insulindependent patients. The patients are acidotic, have serum glucose levels of greater than 250 mg/dL, elevated acetone/ ketone bodies and generally are dehydrated [71]. It may be fatal in 1% 5% of the patients, with about one-third of all cases presenting without a history of diabetes mellitus.

Creatinine Creatinine in the clinical setting is often measured on serum samples. However, in the postmortem arena, serum is rarely obtained; the sample is usually a hemolyzed blood specimen. Nishida et al. [72] evaluated a high performance liquid chromatographic (HPLC) method using whole blood samples taken

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

from 77 autopsy cases. The authors found that the median blood concentration was 1.15 mg/dL (normal clinical values range from 0.4 to 1.2 mg/dL), with no site dependency. They noted that the concentration was stable for about 3 days, which is consistent with the stability found using an enzymatic method on serum samples obtained early in the postmortem interval. The authors found that the creatinine concentration was higher in cases of blunt force trauma, intoxication, and in fire deaths. This finding is consistent with those reported by Zhu et al. [73]. Nishida et al. [72] attributed the increase in creatinine to acute renal failure. However, there were some cases without evidence of renal dysfunction that the creatinine concentrations were also elevated. In an experiment with mice, they determined that the increase in creatinine was associated with the onset of rigor mortis. The authors concluded that creatinine determination, using HPLC, would be useful in the postmortem evaluation of renal function.

Glycated Hemoglobin (HbA1c) Diabetes mellitus is a disease that afflicts many individuals. In the clinical setting, the measurement of blood glucose can determine a hyper- or hypoglycemic state. However, the measurement of postmortem blood for glucose is unreliable, since in the agonal stages of life there can be significant increase in blood glucose concentration [10]. An acute state of hyperglycemia in a decedent may be determined by the measurement of glucose in the vitreous humor. However, it may not be available and will not be an indicator of long-term glucose control. HbA1c is a glycoprotein formed by the nonenzymatic addition of glucose to hemoglobin. The concentration of HbA1c will increase with increased blood glucose concentrations representing the mean blood concentration over a 6 8-week period. The measurement of postmortem blood HbA1c has been used as a marker for the determination of long-term glucose control in the decedent [74]. Winecker et al. [75] evaluated HbA1c in 76 postmortem samples using a turbidimetric immunoinhibition-based method; encompassing two study populations, diabetics and nondiabetics. The mean percentage of HbA1c in nondiabetics was 5.8 1 0.3 and in the diabetic population 12.4 1 2.8; with a statistically significant differentiate between the two populations. The authors found that their method was less time consuming than the labor intensive gel electrophoresis or chromatographic methods coupled with gel

163

164

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

electrophoresis measurement of HbA1c. The author did observe slight increases in HbA1c over a period of time and temperature range (7 days and 24 C 35 C); although statically significant, it generally did not alter the interpretation of the case. However, if a sample was on the borderline of upper limit for the normal glycemic range, the change could raise it enough to suggest chronic elevation of glucose in the decedent. The author suggest that decedents with postmortem HbA1c levels less than 6% have normal glycemic control, whereas those above 8.5% is suggestive of chronic hyperglycemia, while those that lie between 6% and 8.4% need follow-up investigation. White et al. [76] evaluated the stability of HbA1c in aviation accident fatalities and volunteers who donate blood. The postmortem samples were preserved with potassium oxalate/sodium fluoride, aliquoted, and stored frozen while the antemortem samples were collected in an EDTA tube and stored at room temperature. The stability of the postmortem samples was evaluated over an 84-day period, while the antemortem samples were evaluated over 54 days. The postmortem samples showed stability over the 84-day study period, and the antemortem samples showed stability over the 54-day time frame. A number of studies have looked at the viability of postmortem HbA1c determinations. However, the analytical methodology utilized varied from study to study. Keltanen et al. [77] evaluated three different methods used to measure postmortem HbA1c; Mono S cation exchange HPLC, affinity chromatography using point-of-care analyzer (BioRad In2itPOC) and a direct enzymatic method (Diazyme Direct Enzymatic HbA1c Assay). The Mono S HPLC system was found to be superior to the other two testing platforms; the other two platforms had inconclusive results for 25% of the tested samples, whereas as the Mon S HPLC system had a 5% failure rate (one sample).

Methemoglobin metHb is normally present in small amounts (,1% 1.5%) in blood. It is a byproduct of hemoglobin oxidation in which the ferrous iron [Fe21] is oxidized to the ferric ion [Fe31] form. This hemoglobin derivative is unable to associate and transport oxygen to tissues, thus leading to hypoxia. Congenital methemoglobinemia is a rare genetic abnormality caused by NADH-cytochrome b5 reductase deficiency [78]. Other drugs and toxins are also known to cause elevations in metHb.

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

Alkyl nitrites are chemical that have been abused recreationally. Inhalation of amyl nitrite [79], butyl nitrite [80], and isobutyl nitrite [81], along with oral ingestion of isobutyl nitrite [82] have all been reported to cause in a dose-dependent fashion the formation of methemoglobinemia. Kinoshita et al. [83] describe a death due to sever methemoglobinemia due to chlorate ingestion. Saito et al. [84] report a case of fatal methemoglobinemia occurring from the application of a liniment which contained high concentrations of sodium nitrite. Carbon monoxide intoxication from automobile exhaust is not an uncommon mechanism for suicide. Since the introduction of catalytic converter on automobiles, there have been death scenes suggestive of carbon monoxide intoxication; however, the measure carboxyhemoglobin has been found to be low. Additional testing has revealed high concentrations of metHb in these victims, with the cause of death being attributed to carbon monoxide intoxication and methemoglobinemia [85]. metHb may also result from smoke inhalation in fire deaths [86], with concentrations reported as high as 37% [87]. Reay et al. [88] discussed the significance and utility of postmortem metHb concentrations as measured spectrophotometrically. The authors concluded that postmortem metHb concentrations are not valid indicator of antemortem methemoglobinemia, with a possible exception of measurement in fire death if the samples are collected and analyzed shortly after the death. However, Domingo et al. [89] assessed 110 decedents, including 3 ‘popper’-related (butyl/isobutyl nitrite) fatalities. Using a spectrophotometric technique, they measured metHb concentrations in the specimens. They found that either high fluctuating values for sample stored at room temperature or values much higher that the original value when stored at 220 C. Blood samples stored at 4 C the metHb values increased slightly (4%) from the original value after 3 weeks of storage. Although the ‘popper’-positive sample size was small (n 5 3), the authors opined that samples stored over several months at 4 C and 220 C, showed significantly higher metHb concentrations as compared to the ‘nonpopper’ controls samples. Varlet et al. [90] suggest that postmortem metHb measurements are valid indicator of antemortem methemoglobinemia if samples are analyzed within 2 weeks, stored at 4 C 6 C and collected in an EDTA tube.

165

166

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

Tryptase Elevated tryptase concentrations may provide supportive evidence for an anaphylactic death. Tryptase has been found to be stable, may be collected in most standard blood tubes and stored at room temperature [91]. The preferred anatomical site for blood collection is a femoral vessel, so that elevation of the tryptase, due to cardiac massage during resuscitation, does not occur. However, McLean-Tooke et al. [92] suggests that tryptase concentrations greater than 110 µg/L in heart blood; a sensitivity of 80%, with a specificity of 92.1%, is supportive of an anaphylactic related death. Xiao et al. [93] evaluated 74 cases, 20 of which the death was attributed to anaphylaxis. Blood samples were collected from the femoral vein, stored at 4 C without preservative. Total tryptase was measured within 7 10 days of procurement of the sample. Significantly higher tryptase concentrations were observe in the anaphylaxis’s group as compared to the control groups. The optimal cut-off value was 43 ng/mL (µg/L); with a sensitivity of 90% and a specificity of 98%. Tse et al. [94] conducted a 5 year retrospective study, evaluating 9 anaphylactic deaths, along with 45 nonanaphylactic deaths. Total tryptase concentration was measured in the collected femoral blood samples. The samples were collected in a plain tube, stored at 4 C, and tested within 7 days. The author proposed a femoral blood cut-off as 53.8 µg/L; with a sensitivity of 89% and specificity of 93%. Randall et al. [95] reports on elevated postmortem tryptase concentrations in cases without evidence of anaphylaxis. The authors tested 49 cases; however, the anatomical site of the blood draw was not indicated. The authors appear to be using a “clinical” cut-off of 1 ng/mL (µg/L). However, Tse et al. [94] states the clinically accepted 95% upper percentile for tryptase is 11.4 µg/L. The author’s data show only one sample (106 µg/L) exceeding the lower proposed femoral blood cut-off of 43 µg/L, and none above the proposed cut-off of .110 µg/L for a cardiac blood sample. The stability of the tryptase must also be considered in the interpretation of the suspected anaphylactic death. Sravan et al. [96] describes a substantial decline in tryptase concentrations in an anaphylactic death. Two separate samples were collected from the same femoral vein 24 hours apart; with the initial measurement being 130 µg/L, and the subsequent sample collected 24 hours from the same femoral vein later declined to 84.4 µg/L. The author suggesting that samples in suspected anaphylactic cases be collected as soon as possible, so that degradation will

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

have a limited impact of the analytical result. Tse et al. [97] makes the same suggestion on early specimen collection. The authors describe an anaphylactic death from a reaction to antibiotic therapy. They reported a total tryptase concentration 72 hours following death and a second sample collected 144 hours after death; with the measured tryptase concentration declining from 522 to 300 µg/L.

References [1] Belsey SL, Flanagan RJ. Postmortem biochemistry: current applications. J Forensic Leg Med 2016;41:49 57. [2] Palmiere C, del Mar Lesta M, Sabatasso S, Mangin P, Augsburger M, Sporkert F. Usefulness of postmortem biochemistry in forensic pathology: illustrative. Legal Med 2012;14:27 35. [3] Ortmann J, Markwerth P, Madea B. Precision of estimating the time of death by vitreous potassium-comparison of 5 different equations. Forensic Sci Int 2016;269:1 7. [4] Coe JI. Postmortem chemistries on human vitreous humor. Am J Clin Pathol 1969;51:741 50. [5] Coe JI. Further thoughts and observations on postmortem chemistry. Forensic Sci Gaz 1973;5:2 6. [6] Mulla A, Massey KL, Kalra J. Vitreous humor biochemical constituents: evaluation of between-eye differences. Am J Forensic Med Pathol 2005;26:146 9. [7] Thierauf A, Musshoff F, Madea B. Post-mortem biochemical investigations of vitreous humor. Forensic Sci Int 2009;192:78 82. [8] Garg U, Althahabi R, Amirahmadi V, Brod M, Blanchard C, Young T. Hyaluronidase as a liquefying agent for chemical analysis of vitreous fluid. J Forensic Sci 2004;49:388 91. [9] McNeil AR, Gardner A, Stables S. Simple method for improving the precision of electrolyte measurements in vitreous humor. Clin Chem 1999;45:135 6. [10] Coe JI, Apple FS. Variations in vitreous humor chemical values as a result of instrumentation. J Forensic Sci 1985;30:828 35. [11] Coe JI. Postmortem peripheral blood glucose and cardiopulmonary resuscitation. Forensic Sci Gaz 1975;6:1 2. [12] Coe JI. Postmortem chemistry update: emphasis on forensic applications. Am J Forensic Med Pathol 1993;14:91 117. [13] Sturner WQ, Sullivan A, Suzuki K. Lactic acid concentrations in vitreous humor: their use in asphyxial deaths in children. J Forensic Sci 1983;28:222 30. [14] Coe JL. Hypothermia: autopsy findings and vitreous glucose. J Forensic Sci 1984;29:389 95. [15] Leahy MS, Farber ER. Postmortem chemistry of human vitreous humor. J Forensic Sci 1967;12:214 22. [16] Naumann HN. Postmortem chemistry of the vitreous body in man. Arch Opthalmol 1959;62:356 63. [17] Swift PGF, Worthy E, Emery JL. Biochemical state of the vitreous humor of infants at necropsy. Arch Dis Child 1974;49:680 5.

167

168

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

[18] Emery JL, Swift PGF, Worthy E. Hypernatraemia and uraemia in unexpected death in infancy. Arch Dis Child 1974;49:686 92. [19] Zilg B, Alkass K, Berg S, Druid H. Interpretation of postmortem vitreous concentrations of sodium and chloride. Forensic Sci Int 2016;263: 107 13. [20] Bhattarai N, Kafle P, Panda M. Beer potomania: a case report. BMJ Case Rep 2010;2010:bcr10.2009.2414. [21] Fenves AZ, Thomas S, Knochel JP. Beer potomania: two cases and review of the literature. Clin Nephol 1996;45:61 4. [22] Coe JI. Vitreous potassium as a measure of the postmortem interval: an historical review and critical evaluation. Forensic Sci Int 1989;42:201 13. [23] Madea B. Is there recent progress in the estimation of the postmortem interval by means of thanatochemistry? Forensic Sci Int 2005;151:139 49. [24] Blumenfeld TA, Mantell CH, Catherman RL, Blanc WA. Postmortem vitreous humor chemistry in sudden infant death syndrome and in other causes of death in childhood. Am J Clin Pathol 1979;71:219 23. [25] Sparks DL, Oeltgen PR, Kryscio RJ, Hunsaker III JC. Comparison of chemical methods for determining postmortem interval. J Forensic Sci 1989;34:197 206. [26] Vaitla P, Vani N. Correlation between vitreous humor potassium and time since death. J Biotech Biochem 2017;3:16 19. [27] Zilg B, Bernard S, Alkass K, Berg S, Druid H. A new model for the estimation of time of death from vitreous potassium levels corrected for age and temperature. Forensic Sci Int 2015;254:158 66. [28] Li W, Chang Y, Cheng Z, Ling J, Han L, Li X, et al. Vitreous humor: a review of biochemical constituents in postmortem interval estimation. J Forensic Sci Med 2018;4:85 90. [29] Bertol E, Politi L, Mari F. Death by potassium chloride intravenous injection: evaluation of analytical detectability. J Forensic Sci 2012;57:273 5. [30] Palmiere C, Scarpelli MP, Varlet V, Baumann P, Michaud K, Augsburger M. Fatal intravenous injection of potassium: is postmortem biochemistry useful for the diagnosis? Forensic Sci Int 2017;274:27 32. [31] Meadow R. Non-accidental salt poisoning. Arch Dis Child 1993;68:448 52. [32] Johnston JG, Robertson WO. Fatal ingestion of table salt by an adult. West J Med 1977;126:141 3. [33] Smith EJ, Palevsky S. Salt poisoning in a two year old child. Am J Emerg Med 1990;8:571 2. [34] Kovacs L, Robertson GL. Disorders of water balance-hyponatremia and hypernatremia. Bailliers Clin Endocrinol Metab 1992;6:107 27. [35] Finberg L, Kiley J, Luttrell CN. Mass accidental salt poisoning in infancy. A study of a hospital disaster. JAMA 1963;20:187 90. [36] Moder KG, Hurley DL. Fatal hypernatremia from exogenous salt intake: report of a case and review of the literature. Mayo Clin Proc 1990;65:1587 94. ¨ nver A. Fatal [37] Yercen N, C ¸ aglayan S, Yu¨cel N, Yaprak I, Ogu¨n G, U hypernatremia in an infant due to salting of the skin. Am J Dis Child 1993;147:716 17. [38] Peker E, Kirimi E, Tuncer O. Severe hypernatremia in newborns due to salting. Eur J Pediatr 2010;169:829 32. [39] Akcan AB. Hypernatremia in a newborn because of salting of the skin. J Paediatr Child Health 2011;47:314 18.

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

[40] Ayaz S, Efe SY. Potentially harmful traditional practices during pregnancy and postpartum. Eur J Contracept Reprod Health Care 2008;13:282 8. [41] Rehm SR. Exogenous hypernatremia. Mayo Clin Proc 1991;66:438. [42] Kaufman T, Monies-Chass I, Hirshowitz B, Bursztein S. Sodium poising: a lethal case of a burned child. Burns 1986;12:293 4. [43] Carter RF, Fotheringham FJ. Fatal salt poising due to gastric lavage with hypertonic saline. Med J Aust 1971;1:539 41. [44] Christie J. ‘I didn’t hurt him I didn’t kill my son’: Mommy blogger who poisoned her five-year-old gives first-ever interview after being found guilty of his murder 2016. www.dailymail.co.uk/home/sitemaparchive/ day_20160408.html. Accessed 13 Oct 2018. [45] Feldman K, Robertson WO. Salt poisoning: presenting symptom of child abuse. Vet Hum Toxicol 1979;21:341 3. [46] Baugh JR, Krug EF, Weir MR. Punishment by salt poisoning. Southern Med J 1983;76:540 1. [47] Ross MP, Spiller HA. Fatal ingestion of sodium hypochlorite bleach with associated hypernatremia and hyperchloremic metabolic acidosis. Vet Hum Toxicol 1999;41:82 6. [48] Hilbert G, Be´dry R, Cardinaud JP, Benissan GG. Euro Bleach: fatal hypernatremia due to 13.3% sodium hypochlorite (Letter). Clin Toxicol 1997;35:635 6. [49] Radojevic N, Bjelogrlic B, Aleksic V, Rancic N, Samardzic M, Petkovic S, et al. Forensic aspects of water intoxication: four case reports and review of relevant literature. Forensic Sci Int 2012;220:1 5. [50] Helwig FC, Schutz CB, Curry DE. Water intoxication: report of a fatal human case with clinical, pathological and experimental studies. JAMA 1935;104:1569 75. [51] Chertow GM, Brady HR. Hyponatraemia from tap-water enema. Lancet 1994;344:748. [52] Raskind M. Psychosis, polydipsia, and water intoxication. Arch Gen Psych 1974;30:112 14. [53] Rendell M, McGrane D, Cuesta M. Fatal compulsive water drinking. JAMA 1978;240:2557 9. [54] Arieff AL, Kronlund BA. Fatal child abuse by forced water intoxication. Pediatrics 1999;103:1292 5. [55] Milroy CM, Clark JC, Forrest ARW. Pathology of deaths associated with “ecstasy” and “eve” misuse. J Clin Pathol 1996;49:149 53. [56] Ohshima T, Kondo T, Sato Y, Takayasu T. Postmortem alcohol analysis of the synovial fluid and its availability in medio-legal practices. Forensic Sci Int 1997;90:131 8. [57] Winek CL, Bauer J, Wahba WW, Collom WD. Blood versus synovial fluid ethanol concentrations in humans. J Anal Toxicol 1993;17:233 5. ¨ yu ¨ Y, Eke M, Cagdir AS, Karaaslan HK. Post-mortem alcohol analysis in [58] Bu synovial fluid: an alternative method for estimation of blood alcohol level in medico-legal autopsies? Toxicol Mech Methods 2009;19:375 8. [59] Madea B, Kreuser C, Banaschak S. Postmortem biochemical examination of synovial fluid a preliminary study. Forensic Sci Int 2001;118:29 35. [60] Tumram NK, Bardale RV, Dongre AP. Postmortem analysis of synovial fluid and vitreous humor for the determination of death interval: a comparative study. Forensic Sci Int 2011;204:186 90. [61] Backer RC, Pisano RV, Sopher IM. The comparison of alcohol concentrations in postmortem fluids and tissues. J Forensic Sci 1980;25:327 31.

169

170

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

[62] Naumann HN. Cerebrospinal fluid electrolytes after death. Proc Soc Exp Biol Med 1958;98:16 18. [63] Fekete JF, Kerenyi NA. Postmortem blood sugar and blood urea nitrogen determinations. Can Med Asoc J 1965;92:970 3. [64] Noor N, Basavaraju K, Sharpstone D. Alcoholic ketoacidosis: a case report and review of the literature. Oxf Med Case Rep 2016;3:31 3. [65] McMahon AJ, Green ST, Sandler M, Hillis WS. Alcoholic ketoacidosis: a case report. Scott Med J 1987;32:183 4. [66] Prabhakar A, Quach A, Zhang H, Terrera M, Jackemeyer D, Xian X, et al. Acetone as biomarker for ketosis buildup capacity a study in healthy individuals under combined high fat and starvation diets. Nutritional J 2015;14:41. Available from: https://doi.org/10.1186/s12937-015-0028-x. [67] Palmiere C, Tettamanti C, Augsburger M, Burkhardt S, Sabatasso S, Lardi C, et al. Postmortem biochemistry in suspected starvation-induced ketoacidosis. J Forensic Leg Med 2016;42:51 5. [68] Frise CJ, Mackillop L, Joash K, Williamson C. Starvation ketoacidosis in pregnancy. Eur J Obstet Gynecol Reprod Biol 2013;167:1 7. [69] Mostert M, Bonavia A. Starvation ketoacidosis as a cause of unexplained metabolic acidosis in the perioperative period. Am J Case Rep 2016;17:755 8. [70] Valkenborgh T, Bral P. Starvation-induced ketoacidosis in bariatric surgery: a case report. Acta Anaesthesiol Belg 2013;64:115 17. [71] Westerberg DP. Diabetic ketoacidosis: evaluation and treatment. Am Fam Phys 2013;87:337 46. [72] Nishida A, Funaki H, Kobayahsi M, Tanaka Y, Akasaka Y, Kubo T, et al. Blood creatinine level in postmortem cases. Sci Just 2015;55:195 9. [73] Zhu B, Ishida K, Quan L, Taniguchi M, Oritani S, Li D, et al. Postmortem serum uric acid and creatinine levels in relation to the causes of death. Forensic Sci Int 2002;125:59 66. [74] Khuu HM, Robenson CA, Brissie RM, Konrad RJ. Postmortem diagnosis of unsuspected diabetes mellitus established by determination of decedent’s hemoglobin A1c level. J Forensic Sci 1999;44:643 6. [75] Winecker RE, Hammett-Stabler CA, Chapman JF, Ropero-Miller JD. HbA1c as a postmortem tool to identify glycemic control. J Forensic Sci 2002;47:1373 9. [76] White VL, Chaturvedi AK, Canfield DV, Garber M. Association of postmortem blood hemoglobin A1c levels with diabetic conditions in aviation accident pilot fatalities. Tech Rep 2001; DOT/FAA/AM-01/12. [77] Keltanen T, Sajantila A, Valonen T, Vanhala T, Lindroos K. Measuring postmortem glycated hemoglobin a comparison of three methods. Legal Med 2013;15:72 8. ¨ ksel D, Senbil N, Yilmaz N, Yarali N, Gu¨rer YK. A rare cause of mental [78] Yu motor retardation: recessive congenital methemoglobinemia type II. Turk J Pediatr 2009;51:187 9. [79] Edwards RJ, Ujma J. Extreme methaemoglobinaemia secondary to recreational use of amyl nitrite. J Accid Emerg Med 1995;12:138 42. [80] Horne MK, Waterman MR, Simon LM, Garriott JC, Foerster EH. Methemoglobinemia from sniffing butyl nitrite. Ann Intern Med 1979;91:417 18. [81] Bradberry SM, Whittington RM, Parry DA, Vale JA. Fatal methemoglobinemia due to inhalation of isobutyl nitrite. J Toxicol Clin Toxicol 1994;32:179 84.

Chapter 11 POSTMORTEM CLINICAL CHEMISTRIES

[82] O’Toole JB, Robbins GB, Dixon DS. Ingestion of isobutyl nitrite, a recreational chemical of abuse, causing fatal methemoglobinemia. J Forensic Sci 1987;32:1811 12. [83] Kinoshita H, Yoshioka N, Kuse A, Nishiguchi M, Tanaka N, Jamal M, et al. A fatal case of severe methemoglobinemia presumably due to chlorate ingestion. Soud Lek 2011;56:43 4. [84] Saito T, Takeichi S, Yukawa N, Osawa M. Fatal methemoglobinemia caused by liniment solutions containing sodium nitrite. J Forensic Sci 1996;41:169 71. [85] Vevelstad M, Morild I. Lethal methemoglobinemia and automobile exhaust inhalation. For Sci Int 2009;187:e1 5. [86] Hoffman RS, Sauter D. Methemoglobinemia resulting from smoke inhalation. Vet Hum Toxicol 1989;31:168 70. [87] Schwerd W, Schultz E. Carboxyhaemoglobin and methaemoglobin findings in burnt bodies. Forensic Sci Int 1978;12:233 5. [88] Reay DT, Insalaco SJ, Eisele JW. Postmortem methemoglobin concentrations and their significance. J Forensic Sci 1984;29:1160 3. [89] Domingo O, Sto¨ver A, Roider G, Graw M. Detection of methaemoglobinaemia and its application in ‘poppers’ abuse: maintain the right balance between reduction and autooxidation during storage. Int J Legal Med 2017;131:369 77. [90] Varlet V, Ryser E, Augusburger, Palmiere C. Stability of postmortem methemoglobin: artefactual changes caused by storage conditions. Forensic Sci Int 2018;283:21 8. [91] Cecchi R. Diagnosis of anaphylactic death in forensics: review and future perspectives. Legal Med 2016;22:75 81. [92] McLean-Tooke A, Goulding M, Bundell C, White J, Hollingsworth P. Postmortem serum tryptase levels in anaphylactic and non-anaphylactic deaths. J Clin Path 2014;67:134 8. [93] Xiao N, Li D, Wang Q, Zhang F, Yu Y, Wang H. Postmortem serum tryptase levels with special regard to acute cardiac deaths. J Forensic Sci 2017;62:1336 8. [94] Tse R, Wong CX, Kesha K, Garland J, Tran Y, Anne S, et al. Post mortem tryptase cut-off level for anaphylactic death. Forensic Sci Int 2018;284:5 8. [95] Randall B, Butts J, Halsey JF. Elevated postmortem tryptase in the absence of anaphylaxis. J Forensic Sci 1995;40:208 11. [96] Sravan A, Tse R, Cala AD. A decline in 2 consecutive postmortem serum tryptase levels in an anaphylactic death. Am J Forensic Med Pathol 2015;36:233 5. [97] Tse R, Garland J, Ahn Y. Decline in 2 serial postmortem tryptase measurements beyond 72 hours after death in an antibiotic-related anaphylactic death. Am J Forensic Med Pathol 2018;39:14 17.

171