Case Series: Hepatic and Splenic Titanium Dioxide Deposition in Association With Intravenous Drug Use.

ABSTRACT: Titanium dioxide is a versatile compound that is found in a variety of consumer products, medical hardware, and pharmaceuticals. Although oral and topical ingestion of this compound is common, intravenous introduction is much less common. We present three cases where significant titanium dioxide deposits were identified in liver and splenic tissue of three decedents, all of whom died of illicit drug overdose in the same geographic area and had fentanyl and its metabolites in blood on postmortem toxicologic testing. At autopsy, liver sections had a granular texture with fine white stippling grossly, and histologic examination of hepatic and splenic tissues showed scattered patches of black granular material with pink birefringence. Energy-dispersive x-ray spectroscopy performed on these tissues revealed the presences of clusters of titanium dioxide. Immunohistochemical staining of both the liver and spleen with CD68 confirmed the titanium dioxide clusters were within macrophages. Intravenous titanium dioxide nanoparticle elimination studies in rats suggest a time sensitive period for this elimination, with a transient period of pigment deposition between 1-58 days following injection. If a time-dependent link between titanium dioxide pigment deposition within tissues and intravenous drug use can be shown, this could be a valuable tool for Pathologists.

Ultrasound Elastographic Measurement of Rigor Mortis in an Animal Model: A Feasibility Study for Improved Time-of-Death Estimates in Forensic Investigations.

OBJECTIVE. The purpose of our study was to assess the feasibility of 2D shear wave ultrasound elastography to quantitatively measure changes of rigor mortis. SUBJECTS AND METHODS. Muscle stiffness of two live pigs and nine sacrificed pigs was measured in kilopascals using ultrasound elastography. The nine sacrificed pigs were divided into three groups of three pigs each and placed in one of three environments at 90°F (32°C), 70°F (21°C), or 34°F (1°C). Ultrasound elastography of five muscles was performed at 1- to 2-hour intervals for up to 50 hours postmortem. For each pig and muscle location, the time to start, peak intensity, duration of peak, and time to decline of rigor mortis were identified from the graphs of muscle stiffness values over time. These outcome variables were then compared across ambient temperature, body weight, and age groups using the Wilcoxon rank sum test. RESULTS. Postmortem measurements show a rise, peak, and decline of muscle stiffness after death. Rigor mortis was highly significantly affected by ambient temperature (p < .001), was significantly affected by body weight (p = .04), and was not significantly affected by animal age or muscle location (facial vs truncal vs limb) (p > .50). Peak intensity of rigor mortis developed more quickly but attained lower levels of muscle stiffness at 90°F (80-100 kPa) compared with 70°F and 34°F (280-300 kPa) (p < .001). The duration of peak rigor mortis and the time to decline of rigor mortis were significantly longer for the lower temperatures (p < .001). CONCLUSION. Two-dimensional shear wave ultrasound elastography can quantifi-ably measure the trajectory of rigor mortis in an animal model. This new approach may have direct implications for human forensic investigations.

Infant Death Following Home Birth: A Case Report of Fatal Neonatal Hypoglycemia.

Infants born to diabetic mothers are at increased risk for symptomatic hypoglycemia and death after birth. A 36-year-old G4P3 mother with a history of gestational diabetes and newly diagnosed type II insulin-dependent diabetes gave birth at home, in the care of a midwife, to a macrosomic infant girl (10 lbs.). Several hours after birth, the infant became lethargic and was found to be hypoglycemic (blood sugar: 28 mg/dL). Glucose and sugar water were administered by the midwife; however, the infant continued to decompensate. Emergency medical services were called, and the infant was transported to the hospital where, despite resuscitative efforts, she died. An autopsy and review of the literature was performed. At autopsy, characteristic features of maternal-fetal glucose dysregulation were identified, including fetal macrosomia, cardiomegaly, hepatomegaly, and severe pancreatic islet cell hypertrophy/hyperplasia. Developmental abnormalities and other potential causes of death were not identified. Although deaths due to hypoglycemia cannot be reliably diagnosed postmortem using vitreous glucose levels, a clinical history of maternal glucose dysregulation in combination with certain gross and histologic findings should prompt a pathologist to consider maternal-fetal glucose dysregulation as a diagnosis of exclusion and cause of death.

Fatal adrenal crisis due to Addison's disease arising in the context of autoimmune polyglandular syndrome type 1.

The autoimmune polyglandular syndromes (APS) are rare immune-mediated endocrinopathies causing destruction of multiple endocrine and non-endocrine organs. Involvement of adrenal glands associated with any type of APS results in Addison's disease. While patients with Addison's disease often suffer from symptoms of neuroglycopenia, lethal hypotension and hypoglycemia are uncommon. Here, we report a fatal case of APS type 1 with hypotension and profound hypoglycemia in a 24-year-old man who was found unconsciousness at home and progressively evolved into pulseless electrical activity. Although his condition was initially considered to be possibly due to drug toxicity, subsequent drug screening tests failed to detect alcohol or any other substances. Emergent medical evaluation revealed severe hypotension (51/30 mm/Hg) and profound hypoglycemia (blood glucose of 20-30 mg/dl). Despite vigorous supportive care, the patient died following 3 days of respiratory dependency due to irreversible anoxic brain injury. Postmortem examination revealed severely atrophic adrenal glands with lymphocytic infiltration. Subsequent review of the patient's medical history and correlation with autopsy findings confirmed the presence of multiple organ involvement, consistent with APS type 1. This case serves as a reminder for forensic pathologists that death from an acute adrenal (Addisonian) crisis, while uncommon, should remain a differential diagnostic consideration. Furthermore, it underscores the fact that Addison's disease can occur as part of a constellation of autoimmune manifestations within the context of an underlying polyglandular syndrome, such as APS type 1.

The Shock of Strep: Rapid Deaths Due to Group a Streptococcus.

Streptococcus pyogenes, also known as group A beta-hemolytic strep, is a Gram positive coccus responsible for several million infections every year. The types of infections vary widely from pharyngitis to myositis, but all can advance to severe life threatening invasive disease. Of those infected, approximately 1100 to 1600 people die each year due to invasive disease. Why certain individuals contract severe infections is not known, but many strains of Streptococcus pyogenes are known to produce toxins and superantigens. Invasive Streptococcus pyogenes infections have been shown to cause significant morbidity and rapid mortality. In many cases, patients expire before full antemortem testing can be performed, causing physicians and families to look to forensic pathologists for answers. Understanding the pathogenesis of invasive group A strep infections, relevant gross and microscopic findings, and proper culturing techniques is critical for forensic pathologists to diagnosis this condition and assist in the education and protection of the communities they serve.

Death Due to Complications of Bowel Obstruction Following Raw Poppy Seed Ingestion.

Eating poppy seeds can cause a positive urine drug screen, but it is unknown whether ingesting large quantities can result in opiate intoxication or toxicity. A 54-year-old woman with intractable vomiting was found unresponsive at home and later pronounced dead. At autopsy, a cast-like large bowel obstruction composed of poppy seeds was identified. Postmortem blood morphine level was < 10 ng/mL. Cause of death was determined to be complications of a bowel obstruction secondary to poppy seed ingestion. Deaths related to eating poppy seeds have not been described in the literature. This case illustrates that consuming raw poppy seeds in large quantities did not cause lethal opiate toxicity. However, overdose deaths associated with ingesting poppy seed tea (PST) have been described. Poppy seed derivatives should be considered a potential source in cases of opiate toxicity without evidence of prescription or street drug abuse.

Fatal Myocarditis Following Treatment with the PD-1 Inhibitor Nivolumab.

Therapeutic antibodies targeting the programmed cell death protein 1 (PD-1) pathway function as immune checkpoint inhibitors, allowing the immune system to recognize tumors which otherwise escape immune surveillance. However, these agents can also elicit an autoimmune response by inhibiting the ability of non-neoplastic tissues and regulatory cells to suppress the immune system. Here we present a fatal case of active myocarditis in a 55-year-old man with non-small-cell lung cancer which occurred following monotherapy with the PD-1 inhibitor nivolumab (Opdivo). He presented with acute right-sided heart failure and died 1 day after admission. Postmortem examination revealed multiple gelatinous lesions in the myocardium of the interventricular septum and the bilateral atria and ventricles which had microscopic features diagnostic of myocarditis. Subsequent studies failed to identify an infectious cause. Immune checkpoint inhibitors are an increasingly common addition to anticancer regimens and they should be considered in the evaluation of acute myocarditis.

Does Sudden Unexplained Nocturnal Death Syndrome Remain the Autopsy-Negative Disorder: A Gross, Microscopic, and Molecular Autopsy Investigation in Southern China.

OBJECTIVE: To look for previously unrecognized cardiac structural abnormalities and address the genetic cause for sudden unexplained nocturnal death syndrome (SUNDS). METHODS: Data for 148 SUNDS victims and 444 controls (matched 1:3 on sex, race, and age of death within 1 year) were collected from Sun Yat-sen University from January 1, 1998, to December 31, 2014, to search morphological changes. An additional 17 patients with Brugada syndrome (BrS) collected from January 1, 2006, to December 31, 2014, served as a comparative disease cohort. Target-captured next-generation sequencing for 80 genes associated with arrhythmia/cardiomyopathy was performed in 44 SUNDS victims and 17 patients with BrS to characterize the molecular spectrum. RESULTS: The SUNDS victims had slight but statistically significant increased heart weight and valve circumference compared with controls. Twelve of 44 SUNDS victims (SCN5A, SCN1B, CACNB2, CACNA1C, AKAP9, KCNQ1, KCNH2, KCNJ5, GATA4, NUP155, ABCC9) and 6 of 17 patients with BrS (SCN5A, CACNA1C; P>.05) carried rare variants in primary arrhythmia-susceptibility genes. Only 2 of 44 SUNDS cases compared with 5 of 17 patients with BrS hosted a rare variant in the most common BrS-causing gene, SCN5A (P=.01). Using the strict American College of Medical Genetics guideline-based definition, it was found that only 2 of 44 (KCNQ1) SUNDS and 3 of 17 (SCN5A) patients with BrS hosted a "(likely) pathogenic" variant. Fourteen of 44 SUNDS cases with cardiomyopathy-related variants had a subtle but significantly decreased circumference of cardiac valves, and tended to die on average 5 to 6 years younger compared with the remaining 30 cases (P=.02). CONCLUSION: We present the first comprehensive autopsy evidence that SUNDS victims may have concealed cardiac morphological changes. SUNDS and BrS may result from different molecular pathological underpinnings. The distinct association between cardiomyopathy-related rare variants and SUNDS warrants further investigation.

Enhancing preclinical year pathology exposure: the Angevine approach.

Less than 2% of graduating US medical seniors select pathology residencies. One major obstacle to attracting prospective residents is the relative "invisibility" of pathology; medical students lacking positive preclinical exposure to pathology are unlikely to later select pathology clerkships or residencies. The Angevine Fellowship is a 10-week competitive pathology internship medical students may apply for the summer following their first year of preclinical training at our institution. We sought to determine whether it was an effective pathology recruitment tool and how it compared with the postsophomore pathology fellowship (PSF). Angevine fellow and PSF data from 2000 to 2014 were retrospectively analyzed. Specialty choices of former fellows already matched into residency programs were tabulated. Data regarding annual percentage of graduating seniors at our institution who matched into pathology during the years former fellow cohorts matched were also examined. Our results showed that of the former Angevine fellow cohorts already matched into residency programs, 40% (8/20) matched in pathology and 20% (4/20) at our own institution. Angevine fellows comprised a disproportionately high number of the graduating seniors matching in pathology at our medical school (26.7%). PSFs comprised 6.67%. Although we have endowment funding for 2 Angevine fellows annually, the level of interest among applicants has increased to the point that our department has consistently contributed funding for 1-2 additional fellowship spots since 2011. We conclude that the Angevine Fellowship offers an effective alternative to the postsophomore fellowship. It has proven successful at our institution and could be implemented at others to potentially improve pathology recruitment trends nationwide.

Eosinophilic Coronary Periarteritis with Arterial Dissection: The Mast Cell Hypothesis.

A subset of coronary arterial dissections is associated with eosinophilic coronary periarteritis (ECPA); however, the pathogenesis of the process remains unclear. Mast cells normally reside in coronary arterial adventitia and are known mediators of eosinophilic inflammatory conditions such as type I hypersensitivity reactions. We report two cases in which coronary arterial dissection with ECPA was detected at autopsy. Tryptase, CD68, CD4, CD8, and CD1a immunohistochemical staining was performed to better characterize inflammation. While eosinophils represented a prominent periadventitial inflammatory cell, there were slightly more lymphocytes: CD4/CD8 ratios were within expected reference ranges. There were moderate numbers of macrophages, and few neutrophils or dendritic cells. Numbers of mast cells in dissected versus nondissected sections were compared: adventitial mast cell densities were threefold higher in dissected portions and showed a trend toward increased degranulation. These findings suggest that mast cells may play a role in orchestrating inflammation in cases of ECPA.

Bilateral acute necrosis of the globi pallidi and rhabdomyolysis due to combined methadone and benzodiazepine toxicity.

Methadone continues to be a widely used maintenance therapy for opiate dependence. However, methadone-related deaths have been reported frequently for over 4 decades now. Anoxic brain injury with pulmonary edema secondary to respiratory depression is the recognized mechanism of methadone death, although pathological intracranial findings are rarely described in methadone deaths. A selective area of brain injury has never been reported with methadone use. We present a case of a 23-year-old man who had acute necrosis of the bilateral globi pallidi in the brain and systemic rhabdomyolysis after ingesting methadone and nasally insufflating alprazolam. We also present a review of the literature on deaths following opioid use and associated brain injury.

Muscle patterning in mouse and human abdominal wall development and omphalocele specimens of humans.

Human omphalocele is a congenital defect of the abdominal wall in which the secondary abdominal wall structures (muscle and connective tissue) in an area centered around the umbilicus are replaced by a translucent membranous layer of tissue. Histological examination of omphalocele development and moreover the staging of normal human abdominal wall development has never been described. We hypothesized that omphalocele is the result of an arrest in the secondary abdominal wall development and predicted that we would observe delays in myoblast maturation and an arrest in secondary abdominal wall development. To look for evidence in support of our hypothesis, we performed a histological analysis of normal human abdominal wall development and compared this to mouse. We also conducted the first histological analysis of two human specimens with omphalocele. In these two omphalocele specimens, secondary abdominal wall development appears to have undergone an arrest around Carnegie Stage 19. In both specimens disruptions in the unidirectional orientation of myofibers were observed in the external and internal obliques, and rectus abdominis but not in the transversus abdominis. These latter findings support a model of normal abdominal wall development in which positional information instructs the orientation of myoblasts as they organize into individual muscle groups.

Conditional mutation of fibroblast growth factor receptors 1 and 2 results in an omphalocele in mice associated with disruptions in ventral body wall muscle formation.

BACKGROUND/PURPOSE: We observed that fibroblast growth factor receptors 1 and 2 (Fgfr1, Fgfr2) are expressed during abdominal wall development in mice and hypothesized that conditional mutation of these genes would result in abdominal wall defects. METHODS: Section in situ hybridizations were performed for Fgfr1 and Fgfr2 on wild-type embryos at embryonic day (E) 11.5 and E13.5. Conditional mutation of Fgfr1and Fgfr2 was achieved with a tamoxifen inducible Cre at E8.5. Litters were harvested at E17.5, whole mount photographs were taken, and paraffin sections were generated and stained with hematoxylin and eosin. RESULTS: Fgfr1 was expressed in ectoderm, lateral plate mesoderm, and myoblasts, whereas Fgfr2 was expressed almost exclusively in the early dermis and ectoderm of the abdominal wall. Conditional mutation of both Fgfr2 alleles and one Fgfr1 allele resulted in omphalocele in 38.7% of mutants. Histologic examination in mutants demonstrated disruptions in dermal and muscle development. CONCLUSIONS: Mutant embryos with omphalocele arising from mutation in Fgfr1 and Fgfr2 exhibit disruptions in the development of the secondary abdominal wall structures. These findings are consistent with a model of ventral abdominal wall development in which organization of the muscles and connective tissue (secondary abdominal wall structures) is influenced by positional information emanating from the primary abdominal wall.

Fatal subarachnoid hemorrhage due to ruptured vertebrobasilar aneurysm associated with giant cell arteritis in a child.

A 3 ½-year-old previously healthy female experienced an episode of sudden unresponsiveness witnessed by her mother. Upon arrival to the local hospital, imaging studies of the still unresponsive child revealed severe bilateral "flash" pulmonary edema and diffuse anoxic brain injury. Aggressive resuscitative efforts were unsuccessful, and she was pronounced dead. External examination at autopsy was essentially unremarkable. Internal examination of the head revealed diffuse basilar subarachnoid blood originating from a collapsed, 2 cm irregular aneurysm arising from the junction of the vertebral and basilar arteries. Additionally, multiple calcified subpleural, parenchymal, and hilar nodal pulmonary granulomas were identified. The remaining internal examination, including that of the aorta and its major branches, was unremarkable. Histologic examination of the aneurysm revealed alternating mural attenuation and thickening, the latter resulting from prominent intimal proliferation with active fibroplasia. Most notably, numerous isolated and clustered multinucleated giant cells were seen, most prominently in areas of more intense inflammation. Specific immunolabeling and silver staining of the pulmonary granulomas revealed evidence of histoplasmosis, but both were negative for fungal elements in the aneurysm, as was ultrastructural examination. The cause of death is fatal subarachnoid hemorrhage due to rupture of a vertebrobasilar artery aneurysm caused by isolated intracranial giant cell arteritis.

Perforation of the appendix from intestinal mucormycosis in a neonate.

A premature neonate had pneumoperitoneum 5 days after discontinuation of extracorporeal membrane oxygenation therapy. A perforated appendix was found at exploratory laparotomy. Pathologic examination of the appendix found mucormycosis.