Clinical utility of factor V leiden (R506Q) testing for the diagnosis and management of thromboembolic disorders

OBJECTIVE: To review the current state of the art regarding the role of the clinical laboratory in diagnostic testing for the factor V Leiden (FVL) thrombophilic mutation (and other protein C resistance disorders), and to generate, through literature reviews and opinions of recognized thought-leaders, expert consensus recommendations on methodology and diagnostic, prognostic, and management issues pertaining to clinical FVL testing. DATA SOURCES, EXTRACTION, AND SYNTHESIS: An initial thorough review of the medical literature and of current best clinical practices by a panel of 4 experts followed by a consensus conference review, editing, and ultimate approval by the majority of a panel of 28 additional coagulation laboratory experts. CONCLUSIONS: Consensus recommendations were generated for topics of direct clinical relevance, including (1) defining those patients (and family members) who should (and should not) be tested for FVL; (2) defining the preferred FVL laboratory testing methods; and (3) defining the therapeutic, prophylactic, and management ramifications of FVL testing in affected individuals and their family members. As FVL is currently the most common recognized familial thrombophilia, it is hoped that these recommendations will assist laboratorians and clinicians caring for patients (and families) with this common mutation.     

Antithrombin deficiency: issues in laboratory diagnosis

OBJECTIVE: To review the current understanding of the pathophysiology of antithrombin deficiency and its role in congenital thrombophilia. Recommendations for diagnostic testing of antithrombin function and concentration, derived from the medical literature and consensus opinions of recognized experts in the field, are included. These recommendations specify whom, how, and when to test. DATA SOURCES: Review of the published medical literature. DATA EXTRACTION AND SYNTHESIS: A summary of the medical literature and proposed testing recommendations were prepared and presented at the College of American Pathologists Conference XXXVI: Diagnostic Issues in Thrombophilia. After discussion at the conference, consensus recommendations presented in this article were accepted after a two-thirds majority vote by the participants. CONCLUSIONS: Antithrombin deficiency is an infrequent genetic abnormality that may be a significant contributing cause of thrombophilia. Antithrombin deficiency also may be observed in conjunction with other genetic or acquired risk factors. Assay of antithrombin plasma levels is appropriate in the laboratory evaluation of individuals with thrombophilia, preferably using a functional, amidolytic antithrombin assay. The diagnosis of antithrombin deficiency should be established only after other acquired causes of antithrombin deficiency, such as liver disease, consumptive coagulopathy, or heparin therapy, are excluded. A low antithrombin level should be confirmed with a subsequent assay on a fresh specimen, and family studies may be helpful to establish the diagnosis. Antigenic antithrombin assays may be of benefit in subclassification of the type of antithrombin deficiency and to confirm the decreased antithrombin level in patients with type I deficiency.     

Catheter-Related Central Venous Thrombosis: The Development of a Nationwide Consensus Paper in Italy

Catheter-related central venous thrombosis is a serious complication in patients who need long-term venous access. Though scientific data and clinical experience are steadily increasing, many uncertainties still exist about several aspects of this complication, including etiology, pathogenesis, diagnosis, management, and prevention of this complication. The GAVeCeLT (the Italian Study Group for Long Term Central Venous Access) promoted a nationwide consensus, and 12 experts reviewed systematically all the available literature. A preliminary document was presented and discussed during a specific Consensus Meeting, in front of a panel of more than 80 experts (representing different health professions and disciplines). This led to a prefinal document, which was presented to more than 800 health professionals. After peer review by an external board of experts, the final document was prepared. In this article, methodology and results of the consensus are presented.     

Treatment of patients with cardiac surgery associated-acute kidney injury

Members of the Acute Dialysis Quality Initiative (ADQI) participated in a 3-day conference in Vicenza in May 2007 to evaluate the available literature on this topic and draft consensus recommendations for research studies in this area. This report summarizes the available evidence and describes the key questions that will need to be addressed with the goal of standardizing the care of patients with cardiac surgery-associated acute kidney injury (CSA-AKI) and improving outcomes.     

血管血栓性疾病的发病机制和防治

血管血栓性疾病是多发病、常见病,它严重危害人类健康。其发病机制是血管中血栓形成,引起血栓形成的因素很多,危险因素有基因、环境和生活行为(如吸烟)。动脉血栓形成的基础病变是动脉粥样硬化,血小板黏附聚集在动脉血栓形成中起“扳机”作用,静脉血栓形成的主要因素是淤血和高凝。预防动脉血栓形成主要是降血脂和抗血小板黏附、聚集,而预防静脉血栓形成则抗凝和采取措施减轻淤血。动脉血栓的治疗方案主要是溶血栓和/或经皮冠脉介入术(PC I),静脉血栓的治疗方案主要是抗凝。此外,本文还介绍了微血管血栓的形成机制和防治。     

Updated clinical practice recommendations for managing children with 22q11.2 deletion syndrome

This review aimed to update the clinical practice guidelines for managing children and adolescents with 22q11.2 deletion syndrome (22q11.2DS). The 22q11.2 Society, the international scientific organization studying chromosome 22q11.2 differences and related conditions, recruited expert clinicians worldwide to revise the original 2011 pediatric clinical practice guidelines in a stepwise process: (1) a systematic literature search (1992-2021), (2) study selection and data extraction by clinical experts from 9 different countries, covering 24 subspecialties, and (3) creation of a draft consensus document based on the literature and expert opinion, which was further shaped by survey results from family support organizations regarding perceived needs. Of 2441 22q11.2DS-relevant publications initially identified, 2344 received full-text reviews, including 1545 meeting criteria for potential relevance to clinical care of children and adolescents. Informed by the available literature, recommendations were formulated. Given evidence base limitations, multidisciplinary recommendations represent consensus statements of good practice for this evolving field. These recommendations provide contemporary guidance for evaluation, surveillance, and management of the many 22q11.2DS-associated physical, cognitive, behavioral, and psychiatric morbidities while addressing important genetic counseling and psychosocial issues.     

Acquired activated protein C resistance caused by lupus anticoagulants

Lupus anticoagulants (LA) can cause acquired activated protein C resistance (APC-R), but the clinical significance is unclear. To investigate thrombosis and acquired APC-R in patients with LA, we enrolled all 132 patients undergoing hypercoagulability testing with positive LA results and in whom APC-R (with factor V-deficient plasma) was performed during a 2.5-year period. Among 121 patients without factor V Leiden, 24.0% had acquired APC-R; retrospective and prospective (mean follow-up, 2.0 years) thrombotic events were analyzed. The distribution of venous vs arterial thrombosis was different for APC-R vs no APC-R (P = .0064). The majority (19/29 [66%]) with acquired APC-R experienced venous thrombosis, whereas a minority experienced arterial thrombosis (9/29 [31%]; P = .017). The opposite pattern occurred among patients without APC-R (arterial thrombi more common than venous thrombi). After excluding thrombotic events more than 5 years from a positive LA test, venous thrombosis occurred in 62% with (18/29) vs 32% without (29/92) APC-R (P = .0045); and arterial thrombosis in 28% with (8/29) vs 51% without (47/92) APC-R (P = .033). Patients with acquired APC-R due to LA had more venous thrombosis than did patients with LA without APC-R and experienced venous more often than arterial thrombosis.     

Consensus minimum standards for use in a trainer''s report for summative assessment in general practice.

BACKGROUND: Summative assessment of general practitioner registrars is to be introduced in September 1996, one component of which will be a report by the trainer. Standards must be set and guidance provided as to the most appropriate ways of obtaining evidence for the trainer's assessment. AIM: The first aim of this study was to set consensus minimum standards for 30 items that are likely to form the content of a trainer's report; the second aim was to provide a consensus view on the most appropriate methods of assessment to be used by trainers. METHOD: A consensus conference was held in March 1995 during which the 30 items were discussed by a group of 30 general practitioners, of whom 27 were experienced trainers. This resulted in a draft document that was circulated to the conference attenders and other experts for consultation. RESULTS: Draft minimum standards were produced for all 30 items after the consensus conference with a mean of 2.5 standards for each item. Of those involved in the consultation exercise, 82% replied. Most of the revisions suggested at this stage were of a minor nature; the only major revision was to divide one item into two, resulting in a final total of 31 items. All but one of the 80 standards could be assessed by direct observation; 41 (51%) could be assessed by tutorial-based discussion and 61 (76%) by methods specific to that standard. Trainers or their practice partners were viewed as acceptable sources of evidence for all items and hospital consultants and primary health care team members were viewed as acceptable for just over half of the items. CONCLUSION: Standards for use by trainers when providing a general practitioner report for the summative assessment of registrars have been developed by consensus conference and have been subjected to review by consultation. Acceptable methods by which registrars could be assessed against these standards, and suitable personnel who could provide evidence, have also been suggested.     

Viral hepatitis: Croatian consensus statement

There has been a dramatic improvement in diagnostic procedures and therapy of viral hepatitis in the last 20 years. Improvements in therapy caused an increase in actual cost, however, with significant long-term savings through a decreased cost of treatment of advanced liver disease including liver transplantation. The Croatian National Board for Viral Hepatitis has decided to initiate the organization of consensus conference on viral hepatitis enabling the leading experts in the country to give the best possible recommendations for the diagnosis, prophylaxis and therapy in our circumstances. The Consensus Conference took place in Zagreb in June 2004, with update in March 2005, organized by the Croatian National Board for Viral Hepatitis, Reference Centers of the Ministry of Health for Chronic Liver Diseases, Infectious Diseases and AIDS, Croatian Society of Gastroenterology--Hepatology Section, Croatian Society for Nephrology, Dialysis and Transplantation, and Croatian Institute for Health Insurance. Invited experts provided written reports on the respective subjects that appear in this issue and their recommendations resulting in this consensus statement.