Expert opinion on medical diagnostics最新文献

Introduction : Leukoencephalopathies (LEs) are a diverse group of diseases involving cerebral white matter. Some of the disorders may be infectious or immunologically mediated and, therefore, tend to be more amenable to treatment. Most of these disorders have a genetic basis, for which genetic counseling becomes important as currently very few of them have effective therapies. Areas covered : This review calls attention to the diagnostic dilemmas, highlights the diagnostic tests of choice for separating conditions with similar clinical, laboratory or neuroimaging findings, and describes several LEs that have been newly discovered within the last 20 years. Imaging of LEs has progressed rapidly since the introduction of magnetic resonance imaging (MRI) and spectroscopy (MRS), allowing recognition of new diseases, with and without identifiable corresponding biochemical or genetic defects. The distinguishing MRI and MRS features of LEs are described, as well as the resources available for biochemical, CSF and blood sample testing for diagnosis and differentiation from previously known LEs. Expert opinion : Although there is no treatment at present for many of the LEs, their detection as a cause of intellectual and motor disabilities, and as inherited disorders, makes it necessary to accurately categorize them. This knowledge will then allow further elucidation of the etiology, understanding the biological underpinnings, and eventually progress toward rational therapies.

Introduction: Approximately 30% of patients with epilepsy do not respond to adequate medication and are candidates for surgical treatment. Outcome predictors can improve the selection of more suitable treatment options for each patient. Therefore, the authors aimed to review the role of neuroimaging studies in predicting outcomes for both clinical and surgical treatment of epilepsy.

Areas covered: This review analyzes studies that investigated different neuroimaging techniques as predictors of clinical and surgical treatment outcome in epilepsy. Studies involving both structural (i.e., T1-weighted images and diffusion tensor images) and functional MRI (fMRI) were identified, as well as other modalities such as spectroscopy, PET, SPECT and MEG. The authors also evaluated the importance of fMRI in predicting memory outcome after surgical resections in temporal lobe epilepsy.

Expert opinion: The identification of reliable biomarkers to predict response to medical and surgical treatments are much needed in order to provide more adequate patient counseling about prognosis and treatment options individually. Different neuroimaging techniques may provide combined measurements that potentially may become these biomarkers in the near future.

INTRODUCTION: Long-term immunosuppressive therapy represents a huge burden on transplant recipients, but currently cannot be omitted. Improving long-term transplant outcome by immunosuppressive drug withdrawal may be achieved in patients who have developed (partial) immunological unresponsiveness towards their graft, either spontaneously or through tolerance induction. Reliable biomarkers are essential to define such immunological unresponsiveness and will facilitate controlled immunosuppressive drug weaning as well as provide surrogate end-points for tolerance induction trials. AREAS COVERED: Tolerance biomarkers have been defined for both liver and kidney transplantation and can accurately identify operationally tolerant transplant recipients retrospectively. These two tolerance fingerprints are remarkably different, indicating the involvement of distinct mechanisms. Limited data suggest that tolerance biomarkers can be detected in immunosuppressed transplant recipients. Whether these patients can safely have their immunosuppressive drugs withdrawn needs to be established. EXPERT OPINION: Mechanistic interpretation of the kidney transplant tolerance biomarker profile dominated by B cell markers remains a challenge in light of experimental evidence suggesting the pivotal involvement of regulatory T cells. Therefore, defining animal models that resemble human transplant tolerance is crucial in understanding the underlying mechanisms. Additionally, to ensure patient safety while monitoring for tolerance, it is essential to develop biomarkers to non-invasively detect early signs of rejection as well.

Introduction: The use of hyperpolarized molecules allows one to obtain information about metabolism in both cells and animals; such a task represents a tremendous advancement with respect to the results achieved so far with in vivo NMR techniques. Pyruvate appears an excellent tumor biomarker as it allows the attainment of early diagnosis, stadiation and monitoring of response to therapy.

Areas covered: As pyruvate conversion to lactate in the glycolytic pathway is highly enhanced in tumor cells, the 1-(13)C-lactate levels after administration of hyperpolarized 1-(13)C-pyruvate are markedly higher in tumor tissues and depend on the type and grade of the tumor. This review covers the most recent research results (both in vitro and in vivo) about the use of hyperpolarized 1-(13)C-pyruvate for tumor localization, stadiation and for monitoring the response to therapy. The technique may find application in clinics, especially when other imaging modalities are of difficult applicability.

Expert opinion: While (13)C-pyruvate has been shown to be the candidate of choice for metabolic imaging, high expectations are present in the scientific community to see if other hyperpolarized substrates could provide more specific and sensitive biomarkers. The use of hyperpolarized molecules will have a tremendous impact in the armory of diagnostic tools.

Introduction: The current definition of preeclampsia is based on convention and not on maternal and/or perinatal outcomes. This article reviews some of the limitations of the conventional definition of preeclampsia and recent evidence suggesting that there is a dose-response relationship between the magnitude of uteroplacental ischemia and the timing of onset of preeclampsia.

Areas covered: This clinical opinion reviews the limitations of the conventional cutoff for 24-h proteinuria during pregnancy, problems with blood pressure measurement in pregnant women and recent insights into the pathophysiology of preeclampsia including the role of angiogenic imbalances.

Expert opinion: New criteria to redefine preeclampsia has to rely on studies that compare the degree of proteinuria, the severity of hypertension and perhaps the magnitude of angiogenic imbalances in relation with maternal and/or perinatal outcomes. We propose a hypothetical sub-classification of preeclampsia according to whether there is evidence of absolute or relative uteroplacental ischemia in view of the lack of placental pathology support for the cutoff of 34 weeks to sub-classify preeclampsia.

Introduction: Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation and the presence of self-reactive autoantibodies. Since the discovery of anti-cyclic citrullinated peptide (anti-CCP) antibodies, several assays have been developed to measure these autoantibodies in RA patients. The first-generation kit offered high specificity, but sensitivity was low. The second-generation IgG anti-CCP antibody assay (CCP2) offered the same high specificity, with greatly improved sensitivity for RA. INOVA Diagnostics, Inc. offers, in addition to CCP2, a third-generation assay with higher sensitivity compared with CCP2 and also a combined IgG/IgA anti-CCP antibody assay.

Areas covered: The review covers the use of INOVA Diagnostics, Inc. multiple anti-CCP antibody assays in early detection of RA, while also comparing these assays with other commercially available methods of measuring anti-CCP antibodies. While most of the review focuses on the significance of these autoantibodies in adult RA patients, their role in juvenile idiopathic arthritis is also discussed.

Expert opinion: Detection of anti-CCP antibodies has emerged as one of the most important disease markers in RA patients. Several methods are available to measure anti-CCP antibodies, and isotyping and identification of citrullination targets are now the next step in further characterizing these autoantibodies.

Introduction: With the advent of CT more than 3 decades ago, we have seen rapid evolution of this technology, so that we are now able to noninvasively accurately image the coronary arterial tree. This has opened up a debate as to the role of this imaging modality in our day-to-day evaluation of acute coronary syndromes. Much recent literature has focused on whether in the acute setting this modality should be incorporated into current evaluation and treatment guidelines.

Areas covered: A comprehensive review of a literature illustrating the utility of CTA in the acute care setting is presented. The paper goes on to address the benefits and challenges of implementation of CTA in the evaluation of acute chest pain syndromes. Alternative guidelines and insights on future directions are presented.

Expert opinion: In this current era where CAD, and more specifically acute chest pain syndromes, remains as a large part of ED visits and also healthcare costs, CTA will play an important role in the diagnosis and treatment of individuals. It remains only a matter of time when this will be implemented in our guidelines, in light of the recent literature and ever improving CTA protocols.

INTRODUCTION: Non-Hodgkin Lymphoma (NHL) is a heterogeneous group of malignancies with over thirty different subtypes. Follicular lymphoma (FL) is the most common form of indolent NHL and the second most common form of NHL overall. It has morphologic, immunophenotypic and clinical features significantly different from other subtypes. Considerable effort has been devoted to the identification of risk factors for etiology and prognosis of FL. These risk factors may advance our understanding of the biology of FL and have an impact on clinical practice. AREAS COVERED: The epidemiology of NHL and FL is briefly reviewed. For FL etiology and prognosis separately, we review clinical, environmental and molecular (including genetic, genomic, epigenetic and others) risk factors suggested in the literature. EXPERT OPINION: A large number of potential risk factors have been suggested in recent studies. However, there is a lack of consensus, and many of the suggested risk factors have not been rigorously validated in independent studies. There is a need for large-scale, prospective studies to consolidate existing findings and discover new risk factors. Some of the identified risk factors are successful at the population level. More effective individual-level risk factors and models remain to be identified.

Unlabelled: Importance of field: Cryptococcal meningitis is a leading cause of death globally among people with AIDS. In sub-Saharan Africa, cryptococcosis is estimated to kill more people than tuberculosis. Cryptococcosis is also an important infectious disease among immunosuppressed patients in countries with advanced medical care. Early diagnosis is the key to effective treatment, particularly in patients in resource-limited settings. A new lateral flow immunoassay (LFA) for cryptococcal antigen (CrAg) allows for rapid and inexpensive diagnosis of cryptococcosis at or near the point of patient contact.

Areas covered: This article reviews the need for improved diagnostics for cryptococcal meningitis and describes the features of an ideal diagnostic. The design of a new LFA for CrAg is described as well as the results of initial clinical evaluation of the CrAg LFA.

Expert opinion: The CrAg LFA is recommended for use with serum, plasma or CSF for diagnosis of cryptococcal meningitis or non-meningeal cryptococcal disease in symptomatic patients. There is a need for further evaluation of LFA for screening of asymptomatic patients. However, the LFA is emerging as a valuable tool for screening of serum or plasma in ART-naive adults with CD4 counts less than 100 cells/mm(3) in geographic regions with a high prevalence of cryptococcal antigenemia. CrAg screening has the potential to identify patients with asymptomatic cryptococcal infection who should receive preemptive antifungal therapy.