Transmission of methicillin-resistant Staphylococcus aureus infection through solid organ transplantation: confirmation via whole genome sequencing.

We describe two cases of donor-derived methicillin-resistant Staphylococcus aureus (MRSA) bacteremia that developed after transplantation of organs from a common donor who died from acute MRSA endocarditis. Both recipients developed recurrent MRSA infection despite appropriate antibiotic therapy, and required prolonged hospitalization and hospital readmission. Comparison of S. aureus whole genome sequence of DNA extracted from fixed donor tissue and recipients' isolates confirmed donor-derived transmission. Current guidelines emphasize the risk posed by donors with bacteremia from multidrug-resistant organisms. This investigation suggests that, particularly in the setting of donor endocarditis, even a standard course of prophylactic antibiotics may not be sufficient to prevent donor-derived infection.

Microwave oven burns to children: an unusual manifestation of child abuse.

Two children sustained full-thickness burns as a result of being placed in microwave ovens. Well demarcated burns occurred on the skin surfaces closest to the microwave-emitting devices. Morbidity was limited to complications of direct thermal effects. One of the children sustained a distinctive pattern of relative sparing of tissue layers without electrical burn features, such as nuclear streaming and charring, at the entrance site. In both instances eventual identification of this unusual etiology was initiated by child abuse concerns.

Effects of storage of blood on stability of hematologic parameters.

The hematologic parameters of blood stored at 4 degrees C and at room temperature were studied. In blood stored at 4 degrees C with intermittent mixing, leukocyte count, hemoglobin, erythrocyte count, mean corpuscular volume (MCV), hematocrit, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration (MCHC), and platelet count showed no statistically significant change for three days. Blood stored at room temperature showed a significant increase in MCV in 24 hours, and corresponding changes occurred in hematocrit and MCHC. It is concluded from these observations that blood from normal healthy donors can serve as an adequate control for the Coulter Counter for three days if kept at 4 degrees C and mixed intermittently.

Myasthenia gravis-associated systemic vasculitis and myocarditis with involvement of the cardiac conducting tissue.

We describe unexpected autopsy findings in an elderly woman with myasthenia gravis (MG) who had myocarditis of the working and conducting myocardium and coronary and renal vasculitis. Myasthenia gravis, characterized by autoantibodies to the acetylcholine receptor in the postsynaptic cell membrane, may be associated with other autoimmune disorders. An additional manifestation of autoimmunity is the presence of heart muscle antibodies, which may be the basis for myocarditis, which has been reported in up to 60% of MG patients at autopsy. Although myocarditis of the working myocardium is rather common, conduction system myocarditis and systemic vasculitis have not been previously reported in MG.

The negative autopsy: sudden cardiac death or other?

One of the most frustrating challenges faced by the forensic pathologist is the inability to determine the cause of death in a young person previously thought healthy. The four steps in the investigation of a sudden death include obtaining the history and scene information, performing a gross and microscopic autopsy, performing appropriate laboratory tests, and making the diagnosis. When examining the heart grossly it is important to preserve the anatomic landmarks, section the coronary arteries closely, and recognize lethal abnormalities such as anomalous origin of the coronary arteries. Specimens useful for toxicologic analysis include whole blood, serum, vitreous humor, gastric contents, bile, urine a purple top tube of blood, and frozen myocardium and spleen. Lethal cardiac diseases with minimal or no anatomic findings include Brugada and Garg's syndromes, the long QT syndrome, and Wolff-Parkinson-White (WPW) syndrome. Consultation with other experts, including cardiac pathologists, cardiologists, electrophysiologists, and molecular biologists, may be helpful in determining a cause of death.

An unusual site for the AV node tumor: report of two cases.

Atrioventricular (AV) node tumors are very uncommon primary cardiac tumors located exclusively in the AV nodal region. The nomenclature has been diverse according to different histogenetic theories proposed since the first description in 1911. Histochemical, ultrastructural, and immunohistochemical studies have demonstrated its endodermal origin. Patients with these tumors can develop complete heart block or sudden death, but the tumor can also be an incidental finding at autopsy. We present two accidental deaths cases in which multiple foci of atrioventricular node tumor (Case 1) and an isolated cyst (Case 2) were observed in the atrial septum, sparing the conduction system.

Pericardial tamponade and death from Hickman catheter perforation.

In February 1995, a 56-year-old female was taken to the operating room for routine placement of a Hickman catheter. Her internist planned palliative chemotherapy for metastatic breast cancer. Using the Seldinger technique, the right subclavian vein was entered and a Hickman catheter was placed. Shortly after extubation and arrival in the postoperative recovery unit, the patient had respiratory and cardiac arrest. Resuscitative efforts, including chest tube placement and pericardiocentesis, were unsuccessful. Autopsy findings included perforation of the superior vena cava, with extension of the catheter in the pericardial sac and associated effusion. Despite the low reported incidence of perforation during placement of central venous catheters, we recommend confirmation of placement by fluoroscopy and instillation of radiopaque dye because of the high mortality associated with this complication.

Inflammatory aneurysm of the aorta, aortitis, and coronary arteritis.

Inflammatory aneurysm of the aorta is not merely a variant of atherosclerosis, but more probably it is a manifestation of a peculiar systemic disease related to idiopathic retroperitoneal and mediastinal fibrosis. Rarely, aortitis and coronary arteritis may coexist with the inflammatory aneurysm; one of each of such unusual cases are described. Because inflammatory aneurysms of the aorta tend to occur in elderly persons, aortitis and coronary arteritis, when present, cannot be distinguished from the concomitant age-related atherosclerosis without a careful histologic examination.

Dissection of the aorta and coronary arteries associated with acute cocaine intoxication.

Acute myocardial ischemia, cardiac arrhythmias, and conduction disturbances are the most common cardiovascular complications of cocaine and its alkaloidal freebase "crack." Cocaine abuse-related acute aortic dissection has been reported only rarely: three cases in the last 5 years. Described herein, to our knowledge, is the first case of cocaine intoxication-associated acute aortic dissection that also involved the coronary arteries, causing sudden death.

Sudden death associated with aortitis and fibrosclerosing disease of the conduction system.

Aortitis is known to complicate a number of autoimmune diseases and syphilis. In most patients with autoimmune disease, arthritis is the initial presentation followed by aortic insufficiency. We report two cases of ostensibly healthy, middle-aged men in whom the initial manifestation of aortitis was sudden death. In each patient, there was extension of inflammation from the aorta into the atrioventricular node. These cases emphasize the importance of examining the conducting system in cases of sudden death associated with aortitis and no grossly evident cause of death. To our knowledge, this is the first report of aortitis presenting as sudden death.

Communication of the coronary sinus with both atria.

The coronary sinus of a healthy 18-year-old man who died of a skull fracture was found to communicate with both the right and left atria. The anomaly can function as an atrial septal defect; thus, it needs recognition in the treatment of a patient with an interatrial shunt with an apparently normal right atrium.

Sudden unexpected death due to coronary giant cell arteritis.

A previously healthy 19-year-old woman died two hours after the sudden onset of severe chest pain. The only gross abnormality seen at the time of autopsy was thrombosis of the left main coronary artery. Microscopic examination of the artery showed eccentric necrotizing arteritis with giant cells, associated with the thrombus. The aorta was infiltrated with lymphocytes, histiocytes, and an occasional giant cell. Sudden cardiac death as the initial manifestation of a giant cell arteritis that involves only the coronary artery and aorta is rare.

Unexpected death due to chloramine toxicity in a woman with a brain tumor.

It has been known for years that mixing household cleaning products can be hazardous. Nonetheless, from time to time, episodes of pneumonitis from such mixing occur. Although symptoms range from minor upper respiratory irritation to adult respiratory distress syndrome, deaths are very rare. We present the case of a woman with an undiagnosed oligodendroglioma who mixed bleach and ammonia (resulting in the formation of chloramine gas), and died while cleaning her bathroom. To our knowledge, this is the first such death reported from chloramine gas intoxication.

Pericardial laceration and fatal cardiac herniation in an improperly restrained six-month-old infant.

We present the youngest reported patient to suffer pleuropericardial laceration with fatal cardiac herniation from blunt chest trauma, apparently related to the improper use of an infant restraint device. Pericardial laceration with cardiac herniation occurs infrequently, but should be suspected in this setting when a patient in electromechanical dissociation is unresponsive to standard resuscitation measures.

Homicidal asphyxia by pepper aspiration.

As punishment for lying, the foster mother of a five-year-old white male poured pepper into his throat. He immediately became dyspneic, then apneic, and was pronounced dead about 1 h later. At autopsy, the main stem and several smaller bronchi were occluded with pepper. Mechanisms of asphyxia by pepper include mechanical obstruction of the tracheobronchial tree and mucosal edema caused by the irritant effect of volatile oils in pepper. This rare circumstance represents the second reported fatal case of pepper aspiration and the third reported case overall.

Histologic detection of fat emboli.

We describe a procedure for detection of fat emboli in formalin fixed tissue using osmium tetroxide postfixation. Intravascular fat in tissue postfixed in osmium tetroxide, embedded in epoxy or paraffin, and stained with toluidine blue, hematoxylin, or Oil Red O is more easily visualized than in frozen tissue that is stained with Oil Red O. With these methods, fat emboli may be detected years after the initial autopsy.

Sudden death caused by embolization of trophoblast from hydatidiform mole.

A 16-year-old pregnant female presented to a hospital emergency room with vaginal bleeding and uterine cramping. She underwent a hysterotomy and curettage and, during the procedure, her pulse dropped from 130 to 30 beats/minute, her pO2 fell to 10 mm of mercury, and she could not be resuscitated. At autopsy, she was found to have massive pulmonary embolization of syncytiotrophoblast from a hydatidiform mole of the uterus. This is the sixth reported case of trophoblastic embolization from a hydatidiform mole ending in death. This fatal termination may occur after a period of respiratory symptoms and may occur regardless of the mode of treatment.

Coronary artery compression by teflon pledget granuloma following aortic valve replacement.

We describe a massive fatal posterior myocardial infarct resulting from compression of the right coronary artery by a Teflon pledget granuloma in a patient who had undergone aortic valve replacement six months before death. Other iatrogenic causes of coronary artery occlusion or compression are discussed in this paper. To our knowledge this is the first report of this surgical complication.

Sudden death in hemodialysis patients.

Hemodialysis patients may die suddenly and unexpectedly from a number of causes. These may be divided into those deaths due directly to and occurring during hemodialysis, those deaths occurring while the patient is not undergoing dialysis, and those deaths that may occur at any time. The first group includes brain herniation, air embolism, acute hemorrhage as a result of machine malfunction or fistula rupture, electrocution, cardiac arrhythmia caused by hypokalemia, complications of subclavian intravenous catheter insertion, third-degree heart block as a result of triglyceride emulsion, and disseminated intravascular coagulation (DIC) or hyperkalemia caused by overheated dialysate. The second group includes deaths due to pericardial tamponade because of effusion and suicidal causes of death (exsanguination, electrolyte imbalance as a result of excessive intake of salt, fluid, or potassium) as well as more conventional methods of suicide. The last category includes people dying of arteriosclerotic cardiovascular disease, hypertensive cardiovascular disease, and internal hemorrhage. Investigation of these deaths, including pertinent historical, laboratory, and autopsy data and investigation of dialysis equipment, is discussed.

Spontaneous clostridial myonecrosis.

Spontaneous, nontraumatic clostridial myonecrosis is a rare infection with an insidious onset and usually fatal outcome. Spontaneous clostridial myonecrosis has a frequent association with colon carcinoma, leukemia, diabetes mellitus, and drug-induced immunosuppression. We present the case of a 73-year-old diabetic man who died of spontaneous Clostridium septicum myonecrosis, who had presented with fulminant gangrene of the right thigh. Clostridium septicum was cultured from the quadriceps muscle postmortem. At autopsy, in addition to the gangrene, there was a Duke's A adenocarcinoma of the cecum, which had not been diagnosed during life. When spontaneous nontraumatic clostridial myonecrosis is diagnosed at autopsy, investigation should include through exam and the obtaining of past medical history in order to elucidate predisposing factors.