North American Journal of Medicine and Science
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Update on HBV Treatment and Management of Antiviral Resistance
Get PDFChronic hepatitis B (CHB) is a major public health problem affecting up to 400 million people globally. Complications of CHB including liver failure and hepatocellular carcinoma result in 1.2 million deaths per year, making CHB the 10th leading cause of mortality worldwide. The natural history of CHB is variable and complex. The past decade witnessed important developments for the therapy of hepatitis B and marked the new era of oral therapy. The ultimate goal of CHB therapy is to arrest the progression of liver injury and to prevent the development of liver failure and hepatocellular carcinoma. Currently, six agents are approved for the treatment of CHB. Each of these agents, given as monotherapy, has been shown to produce virological, biochemical and histological benefits for both HBeAg positive and negative CHB. There are, however, limitations in spite of their efficacy. The significant side-effect profile of interferon, for example, limits its long-term use. The approved oral agents are tolerable with prolonged use but drug resistance could limit long-term monotherapy. To date, combination therapy with nucleoside analogue and pegylated interferon or two nucleos(t)ide analogues given for one year does not show superiority in durability of response compared to monotherapy. Ongoing research effort is critical to identify the ideal hepatitis B therapy that is safe, effective and produces durable response with a finite course of therapy. It is equally important to conduct a well designed, prospective natural history study to identify predictors of disease progression. This will accurately guide treatment strategy for this important disease
Hepatitis B Reactivation during Immunosuppression: From Pathogenesis to Management Strategy
Get PDFHepatitis B is one of the most common viral hepatitis that poses significant health risks in immunocompetent and more so in immunocompromised patients. Increasing scientific development and research in the fields of various autoimmune diseases and oncology have led to the evolution of several chemotherapy agents and newer modalities of treatment of these entities resulting in profound immunomodulation or immunosuppression. In the current era of under-diagnozed or under-screened population for hepatitis B, there is potential risk of developing severe or fulminant hepatitis B if such patients are exposed to immunosuppressive agents. This paper outlines the pathophysiology, clinical outcomes and explores the risk factors for hepatitis B reactivation during immunosuppression. Additionally we also propose a simplistic algorithm for the management of hepatitis B reactivation during immunosuppression that can be adopted by physicians taking care of such patients
Diffuse Large B-cell Lymphoma, Differential Diagnosis and Molecular Stratification
Get PDFDiffuse large B-cell lymphoma (DLBCL) is a clinically aggressive lymphoma. The diagnosis of DLBCL is based on morphological and immunophenotypical evaluation of the biopsy specimens. The pathologic diagnosis of DLBCL, while often straight forward, may be challenging from time to time, so much so that the most recent WHO classification of hematolymphoid neoplasms created two provisional categories dealing with the cases in which separation of DLBCL from other lymphomas can not be made with certainty. On the other hand, DLBCL is also a biologically and clinically heterogeneous entity. Treatment outcome in many cases has not been optimal. Research studies have provided new insight into the DLBCL and suggestions for further stratification of the disease to achieve better treatment outcomes. This review will highlight key differentiating points of the many different categories of lymphomas and non-lymphoid malignancies that need to be considered in the differential diagnosis of DLBCL. The current status of prognostic marker studies of DLBCL as an effort to further stratify DLBCL is also reviewed
Systematic Review of the Association between Lipoprotein - Associated Phospholipase A2 and Atherosclerosis
Get PDFLipoprotein-associated phospholipase A2 (Lp-PLA2) is a novel inflammatory biomarker. Basic research has shown that Lp-PLA2 is involved in the pathogenesis of atherosclerosis. In the past decade, an increasing number of epidemiological studies have investigated the association of Lp-PLA2 with atherosclerosis, but its roles in the different stages of atherosclerosis are not established. By undertaking a systematic review of the epidemiological studies on the relationship between Lp-PLA2 and atherosclerotic cardiovascular disease (CVD)/subclinical atherosclerosis, we tried to evaluate the relationship between Lp-PLA2 and the different stages of atherosclerosis. MEDLINE, Cochrane Library, and National Knowledge Infrastructure (CNKI) were searched up to September 1st, 2011. The references in all the located articles were manually searched. Epidemiological studies on the association of Lp-PLA2 with CVD and subclinical atherosclerosis, with total CVD, coronary heart disease (CHD), stroke, and subclinical atherosclerosis as their observation endpoints or outcome variables, were included in this study. Studies which did not assess the hazard ratio (HR), relative risk (RR), or odds ratio (OR) of Lp-PLA2 or which did not adjust for other known risk factors were excluded. The general information, study design, sample size, outcome variables and their definitions, follow-up duration, Lp-PLA2 measurements, variables adjusted in the multivariate analysis and main results in the literatures were retrieved. Thirty-nine studies were enrolled in this systematic review. Thirty-three studies (49, 260 subjects) investigated the relationship between Lp-PLA2 and CVD, among which 31 showed that increased Lp-PLA2 is associated to high risk for incidence or mortality of CVD: HR/RR per 1 standard deviation (SD) increase = 1.17–1.40; RR for the highest as compared with the lowest quartile was 1.41–3.75 (1.8–2.5 in most studies). Six studies (four cross-sectional studies and two case-control studies, with an overall sample size of 5,537) explored the relationship between Lp-PLA2 and subclinical atherosclerosis; among them, two studies demonstrated that Lp-PLA2 was associated with coronary artery calcification in young adults and men. In conclusion, many epidemiological studies have demonstrated that Lp-PLA2 increases the risk of clinical CVD events. However, whether there is a similar association between Lp-PLA2 and subclinical atherosclerosis remains unclear. Whether Lp-PLA2 exerts its effect during the occurrence of clinical events promoted by unstable plaques or at the early stage of atherosclerosis needs to be clarified in further prospective studies
Maternal Diabetes and Autism Spectrum Disorders in the Offspring: A Review of Epidemiological Evidence and Potential Biologic Mechanisms
Get PDFGestational diabetes is a common pregnancy complication whose prevalence is increasing among women of reproductive age and results in both short-and long-term adverse outcomes for the offspring. Hyperglycemia or other consequences of adverse maternal metabolic profiles in pregnancy may contribute to autism risk through several potential mediating mechanisms, such as inflammation, oxidative stress, and epigenetics. The present review aims to summarize recent studies exploring the association between maternal pre-gestational diabetes, gestational diabetes, obesity and autism spectrum disorders (ASD) in the offspring. We will also explore potential biologic mechanisms to explain the association between in utero exposure to a hyperglycemic environment and risk for ASD, including inflammation, oxidative stress and epigenetics. Considering the concurrent rise in obesity and diabetes in pregnancy, as well as the modifiable nature of these disorders, their associations with ASD and the underlying molecular mechanisms should be explored further.
A Rare Case of Mediastinitis Following a Routine Dental Procedure in a Patient with History of Cardiac Surgery
Get PDFMediastinitis is a rare, severe condition associated with increased morbidity and mortality. Mediastinitis, a life-threatening infection, may occur during the postoperative period following cardiovascular surgery. We present a unique case of mediastinitis following a dental procedure in a 47 year old healthy male with a past surgical history of acute type 1 aortic dissection repaired with Dacron tube graft and re-suspension of his aortic valve, 16 months earlier. He was noted to have induration on his right pectoralis muscle and underwent chest Computerized Tomography (CT) scan revealing infectious mediastinitis. His condition improved after CT-guided abscess aspiration and a six-week course of intravenous antibiotics. Mediastinitis may result from an infection extending from the oropharynx inferiorly through deep spaces of the neck as a descending necrotizing mediastinitis. This case suggests that disruption of fascial planes following cardiac surgery may predispose individuals to acquire anterior mediastinitis via a descending pathway long after completion of surgery.
Molecular and Pathophysiological Features of Angiotensinogen: A Mini Review
Get PDFThe renin-angiotensin system is an essential regulatory system for blood pressure and fluid homeostasis. Angiotensinogen is the only known precursor of all the peptides generated in this system. While many of the basic understandings of angiotensinogen have come from research efforts to define its role in blood pressure regulation, novel pathophysiological functions of angiotensinogen have been discovered in the last two decades including kidney developmental abnormalities, atherosclerosis, and obesity. Despite the impressive advance in the understanding of angiotensinogen gene structure and protein functions, some fundamental questions remain unanswered. In this short review, we provide contemporary insights into the molecular characteristics of angiotensinogen and its pathophysiological features. In light of the recent progress, we emphasize some newly recognized functional features of angiotensinogen other than its regulation on blood pressure
Update on the Recommended HBV Screening in the United States
Get PDFHepatitis B virus (HBV) infection is a serious public health problem that can be associated with HBV-cirrhosis and hepatocellular carcinoma (HCC). HBV-related chronic liver disease is particularly prevalent in the Asian population with significant disparity. Although convenient HBV screening and diagnosis tests are safe and effective, HBV vaccination have been available for many years, under-screening and under-diagnosis of HBV infection is still a serious problem in the USA and worldwide. This article systemically reviewed effectiveness of universal HBV vaccination programs that have been implemented in many countries and regions, the facts of HBV under-screening in the U.S., especially in Asian Americans, and the updated recommendations of HBV screening and vaccination by Center of Disease Control and Prevention (CDC).
Management of Initial HBV Therapy for an HBeAg-Negative Patient: A Case Discussion
Get PDFA case study of a 45-year-old Chinese woman with chronic hepatitis B (CHB) diagnosed in 1999 …..
A Pilot Study on the Diagnostic Performance of DMS-IV and DMS-V for Autism Spectrum Disorder
Get PDFThe new diagnostic criteria for autism spectrum disorders (ASD) are due to be released in May 2013. The impact of changes made in the new criteria is yet to be evaluated. Here we performed a retrospective study on a cohort of ASD patients diagnosed by DSM-IV criteria, aimed to compare the diagnostic performances between DSM-IV and DSM-V. We reviewed the medical records of 163 patients with possible clinical diagnosis of ASD. Ninty-three (57%) of them met the DSM-IV criteria for Autistic disorder, the rest 70 cases were either PDD-NOS (n=39) or Asperger’s disorder (n=3) or without sufficient information in medical record to perform a clinical diagnosis (n=28). Upon re-evaluation using the new diagnostic criteria in DSM-V, only 60% of patients with previous diagnosis of autistic disorder met the new criteria. One individual who was previous diagnosed as PDD-NOS met the new diagnostic criteria for autistic disorder. The present study revealed a significant difference in diagnostic yield by new and old criteria. This pilot comparative study reveals that the ASD diagnostic criteria in DSM-V are stricter than that in DSM-IV and autism patients diagnosed using DMS-V criteria tend to be more severely affected. The new criteria will have immediate impact on the clinical diagnosis and management of individuals with neuodevelopmental disorders and it will affect the prevalence estimate of ASD in population as well