Pericarditis: inflammation or infarction?

Pericarditis occurs when there is inflammation of the pericardium, a 2-layer sac that surrounds the myocardium. These layers are separated by 15 to 20 mL of thin serous fluid. The accumulation of serous fluid along with the presence of inflammatory cells and fibrin can compromise cardiac function. The cause of pericarditis can be related to many disorders and often mimics signs of myocardial ischemia or acute myocardial infarction (AMI). Complications such as cardiac tamponade can occur with a large effusion and can be life threatening. It is essential to differentiate pericarditis from AMI. Preservation of heart muscle in AMI is essential as is proper treatment and prevention of complications such as cardiac tamponade, which can occur as a result of pericarditis. This article discusses the common causes, clinical manifestations, diagnostic procedures, and treatment associated with pericarditis.     

Hepatitis B virus-persistent infection and innate immunity defect: Cell-related or virus-related?

The outcomes of hepatitis B virus (HBV) infection are closely related to the age at which infection was acquired. Infection acquired in adult life tends to be self-limited, in contrast to perinatal acquirement, for which chronic persistence of the HBV is a general outcome. Innate immunity plays an indispensable role in early virus infection, facilitating virus clearance. However, it has been reported that HBV is under-recognized and poorly eliminated by the innate immune system in the early stages of infection, possibly explaining the long-lasting persistence of viremia afterwards. Furthermore, due to the existence of covalently closed circular DNA, chronic HBV clearance is very difficult, even when patients are given interferon-α and nucleotide/nucleoside analogs for antiviral therapy. The mechanism by which HBV evades innate immune recognition and establishes persistent infection remains a subject of debate. Besides, some researchers are becoming more interested in how to eradicate chronic HBV infection by restoring or boosting innate immunity. This review aimed to summarize the current knowledge on how intrahepatocyte signaling pathways and innate immune cells act after the onset of HBV infection and how these actions are related to the persistence of HBV. We anticipate the insights presented herein to be helpful for future development of novel immune therapeutic strategies to fight HBV infection.     

Nosocomial infection in neonates: inevitable or preventable?

In the neonatal intensive care unit population the nosocomial infection rate is highest in the lowest-birth-weight infants. It is this group of infants who require the most therapeutic interventions to support them leading to frequent invasive procedures and the longest exposure to the hospital environment. However, infection rates vary from one unit to another, suggesting that there are differences in either how infection rates are determined or the care provided in the various units. This article will describe nosocomial infections and rates in the neonatal intensive care unit and identify strategies of care to minimize the risks of nosocomial infection in low-birth-weight infants.     

Low levels of plasma proteins: malnutrition or inflammation?

Levels of several plasma proteins, including albumin, transferrin, and transthyretin (prealbumin), have been proposed as markers for protein energy malnutrition. However, many other factors, especially inflammatory disease and drug or hormone therapy, affect levels of these proteins. These factors probably account for the majority of low levels of transthyretin. Levels of albumin and other proteins may be helpful in determining increased risk of morbidity and mortality, but better markers are needed for diagnosis of protein energy malnutrition per se.     

Prehospital blood pressures: Inaccuracies caused by ambulance noise?

Blood pressure measurements in a moving ambulance can be difficult to obtain. Sirens, engine noise, and road noise can all interfere with the accurate detection of patient's blood pressure. This study was under-taken to determine the influence of ambulance noise and vibration on auscultated blood pressures. A model was developed that used dynamic pressures to simulate systolic Korotkoff sounds. Forty-nine emergency personnel were asked to obtain blood pressures using the model in both a quiet environment and in a moving ambulance. A total of 485 blood pressure measurements were obtained. Systolic pressures were randomized to two settings: 76 mm Hg and 138 mm Hg. Stationary readings were compared with moving readings using analysis of variance for repeated measures. Systolic blood pressure measurements obtained in the quiet environment averaged 133 ± 5 mm Hg at the high setting, and 45 ± 6 mm Hg at the low setting. Systolic blood pressure measurements obtained in a moving ambulance averaged 86 ± 7 mm Hg at the high setting, and 41 ± 7 mm Hg at the low setting. The average differences between quiet and moving measurements were 47 mm Hg at the “high” setting (P < .01) and 4 mm Hg at the “low” setting (P > .01). At physiological levels, blood pressures obtained in moving ambulances differ significantly from those obtained in a quiet environment, which may be caused by road noise and ambulance motion.     

Pharmacogenetics and pharmacogenomics of thienopyridines: clinically relevant?

Pharmacogenetics have been touted as the future of personalized medicine where genetic biomarkers will guide therapeutic approach. The currently approved thienopyridines, prasugrel and clopidogrel, are prodrugs requiring conversion to active metabolite through the cytochrome P450 system. Genetic variation has been associated with the pharmacokinetic, pharmacodynamic, and clinical response to clopidogrel, but not to prasugrel. This review aims to summarize the recent pharmacogenetic findings associated with the response to thienopyridine treatment. Additionally, considerations for the incorporation of genetic biomarkers into clinical practice will be discussed in the context of thienopyridines.     

Abdominal pain and dysuria in pregnancy: urinary tract infection or life threatening haemorrhage?

This report describes the case of a 27 year old woman presenting at 19 weeks' gestation with epigastric pain and dysuria. Initially diagnosed with a urinary tract infection, she re-presented 10 days later with acute abdominal pain and haemoperitoneum. The diagnosis of placenta percreta was not made until laparotomy. This case highlights placenta percreta as a rare but serious complication of pregnancy that may become increasingly frequent as the rates of caesarean delivery rise. Early diagnosis, close monitoring, and prompt surgical management are essential as massive blood loss can occur. This can be challenging, as clinical presentation can be unusual.     

Childhood H. pylori: disappearing disease or chronic infection?

Helicobacter pylori is one of the commonest chronic bacterial infections worldwide. It is acquired during childhood and its persistence has implications for health in later life. In adults, it is the principle cause of duodenal ulcer disease and there is evidence of an association between H. pylori and gastric cancer. However, most colonized people are asymptomatic. The prevalence of H. pylori increases with age but there is a striking difference between the rates in developed and developing countries. As no significant non-human or environmental source for this infection has been identified, person to person spread is almost certainly the main mode of transmission. Community nurses should be aware of this micro-organism as a potential cause of illness in children, and that they can play a role in promoting hygiene practices and educating families so that the risk of acquisition may be reduced. This review discusses the clinical features, prevalence, risk factors for transmission, diagnosis and treatment of H. pylori.     

Central line-associated bloodstream infection: is the hospital epidemiology of methicillin-resistant Staphylococcus aureus relevant?

We aimed to evaluate the risk factors, including the hospital epidemiology of methicillin-resistant Staphylococcus aureus (MRSA), for central venous line-associated and laboratory-confirmed bloodstream infections (CLA-BSI and LC-BSI, respectively). The risk factors examined included the age and sex of patients, whether or not they were in the surgery service, the number of days of central line (CL) placement, the monthly number of inpatients and those positive for MRSA, and whether the standard or maximal barrier precautions were observed at CL insertion. As the outcome factors, we selected CLA-BSI and LC-BSI, while precluding repeated isolation within 28 days. Of a total of 22 723 device days in 927 patients with CL placement, we observed 81 CLA-BSIs and 40 LC-BSIs, rates of 3.56 and 1.76 (/1000 device-days), respectively. Logistic regression analysis revealed a single significant factor, CL placement of more than 30 days, with odds ratios of 3.038 [95% confidence interval (CI) 1.733–5.326; P < 0.001] for CLA-BSI and 3.227 (95% CI 1.427–7.299; P = 0.005) for LC-BSI. Both BSIs included MRSA in seven events without temporal clusters. We conclude that the factor of long CL placement outweighs other risk factors, including the hospital epidemiology of MRSA.