Guy's and St Thomas' NHS Foundation Trust

About: Guy's and St Thomas' NHS Foundation Trust is a healthcare organization based out in London, United Kingdom. It is known for research contribution in the topics: Population & Randomized controlled trial. The organization has 7686 authors who have published 9631 publications receiving 399353 citations. The organization is also known as: Guy's and St Thomas' National Health Service Foundation Trust & Guy's and St Thomas' National Health Service Trust.

Emerging treatment strategies for trauma-induced coagulopathy

Abstract: Background: Trauma-induced coagulopathy has a multifactorial aetiology. Coagulopathy is related to blood loss including consumption of clotting factors and platelets and haemodilution. Additionally hyperfibrinolysis, hypothermia, acidosis and metabolic changes affect the coagulation system. Methods: This is a review of pathophysiology and new treatment strategies for trauma-induced coagulopathy. Results: Paradigms are actively changing and there is still a shortage of data. The aim of any haemostatic therapy is to control bleeding and minimize blood loss and transfusion requirements. Transfusion of allogeneic blood products as well as trauma-induced coagulopathy cause increased morbidity and mortality. Current opinion is based on present studies and results from small case series, combined with findings from experimental studies in animals, in vitro studies and expert opinions, as opposed to large, randomized, placebo-controlled studies. A summary of new and emerging strategies, including medical infusion and blood products, to beneficially manipulate the coagulation system in the critically injured patient is suggested. Conclusion: Future treatment of trauma-induced coagulopathy may be based on systemic antifibrinolytics, local haemostatics and individualized point-of-care-guided rational use of coagulation factor concentrates such as fibrinogen, prothrombin complex concentrate, recombinant factor VIIa and factor XIII. The authors speculate that timely and rational use of coagulation factor concentrates will be more efficacious and safer than ratio-driven use of transfusion packages of allogeneic blood products. Copyright © 2011 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

SAMBA HIV Semiquantitative Test, a New Point-of-Care Viral-Load-Monitoring Assay for Resource-Limited Settings

Abstract: Routine viral-load (VL) testing of HIV-infected individuals on antiretroviral therapy (ART) is used to monitor treatment efficacy. However, due to logistical challenges, implementation of VL has been difficult in resource-limited settings. The aim of this study was to evaluate the performance of the SAMBA semi-Q (simple amplification-based assay semiquantitative test for HIV-1) in London, Malawi, and Uganda. The SAMBA semi-Q can distinguish between patients with VLs above and below 1,000 copies/ml. The SAMBA semi-Q was validated with diluted clinical samples and blinded plasma samples collected from HIV-1-positive individuals. SAMBA semi-Q results were compared with results from the Roche COBAS AmpliPrep/COBAS TaqMan HIV-1 test, v2.0. Testing of 96 2- to 10-fold dilutions of four samples containing HIV-1 subtype C as well as 488 samples from patients in the United Kingdom, Malawi, and Uganda yielded an overall accuracy for the SAMBA semi-Q of 99% (95% confidence interval [CI], 93.8 to 99.9%) and 96.9% (95% CI 94.9 to 98.3%), respectively, compared to to the Roche test. Analysis of VL data from patients in Malawi and Uganda showed that the SAMBA cutoff of 1,000 copies/ml appropriately distinguished treated from untreated individuals. Furthermore, analysis of the viral loads of 232 patients on ART in Malawi and Uganda revealed similar patterns for virological control, defined as either <1,000 copies/ml (SAMBA cutoff) or <5,000 copies/ml (WHO 2010 criterion; WHO, Antiretroviral Therapy for HIV Infection in Adults and Adolescents: Recommendations for a Public Health Approach, 2010). This study suggests that the SAMBA semi-Q has adequate concurrency with the gold standard measurements for viral load. This test can allow VL monitoring of patients on ART at the point of care in resource-limited settings.

Expert consensus guidelines for the genetic diagnosis of Alport syndrome.

Abstract: Recent expert guidelines recommend genetic testing for the diagnosis of Alport syndrome. Here, we describe current best practice and likely future developments. In individuals with suspected Alport syndrome, all three COL4A5, COL4A3 and COL4A4 genes should be examined for pathogenic variants, probably by high throughput-targeted next generation sequencing (NGS) technologies, with a customised panel for simultaneous testing of the three Alport genes. These techniques identify up to 95% of pathogenic COL4A variants. Where causative pathogenic variants cannot be demonstrated, the DNA should be examined for deletions or insertions by re-examining the NGS sequencing data or with multiplex ligation-dependent probe amplification (MLPA). These techniques identify a further 5% of variants, and the remaining few changes include deep intronic splicing variants or cases of somatic mosaicism. Where no pathogenic variants are found, the basis for the clinical diagnosis should be reviewed. Genes in which mutations produce similar clinical features to Alport syndrome (resulting in focal and segmental glomerulosclerosis, complement pathway disorders, MYH9-related disorders, etc.) should be examined. NGS approaches have identified novel combinations of pathogenic variants in Alport syndrome. Two variants, with one in COL4A3 and another in COL4A4, produce a more severe phenotype than an uncomplicated heterozygous change. NGS may also identify further coincidental pathogenic variants in genes for podocyte-expressed proteins that also modify the phenotype. Our understanding of the genetics of Alport syndrome is evolving rapidly, and both genetic and non-genetic factors are likely to contribute to the observed phenotypic variability.