CONservative TReatment of Appendicitis in Children – a randomised controlled feasibility Trial (CONTRACT)

Objective To establish the feasibility of a multicentre randomised controlled trial to assess the effectiveness and cost-effectiveness of a non-operative treatment pathway compared with appendicectomy in children with uncomplicated acute appendicitis.Design Feasibility randomised controlled trial with embedded qualitative study to inform recruiter training to optimise recruitment and the design of a future definitive trial.Setting Three specialist paediatric surgery centres in the UK.Patients Children (aged 4–15 years) with a clinical diagnosis of uncomplicated acute appendicitis.Interventions Appendicectomy or a non-operative treatment pathway (comprising broad-spectrum antibiotics and active observation).Main outcome measures Primary outcome measure was the proportion of eligible patients recruited. Secondary outcomes evaluated adherence to interventions, data collection during follow-up, safety of treatment pathways and clinical course.Results Fifty per cent of eligible participants (95% CI 40 to 59) approached about the trial agreed to participate and were randomised. Repeated bespoke recruiter training was associated with an increase in recruitment rate over the course of the trial from 38% to 72%. There was high acceptance of randomisation, good patient and surgeon adherence to trial procedures and satisfactory completion of follow-up. Although more participants had perforated appendicitis than had been anticipated, treatment pathways were found to be safe and adverse event profiles acceptable.Conclusion Recruitment to a randomised controlled trial examining the effectiveness and cost-effectiveness of a non-operative treatment pathway compared with appendicectomy for the treatment of uncomplicated acute appendicitis in children is feasible.Trial registration number ISRCTN15830435

A Novel Pathogenic Mechanism of Highly Pathogenic Avian Influenza H5N1 Viruses Involves Hemagglutinin Mediated Resistance to Serum Innate Inhibitors

In this study, the effect of innate serum inhibitors on influenza virus infection was addressed. Seasonal influenza A(H1N1) and A(H3N2), 2009 pandemic A(H1N1) (H1N1pdm) and highly pathogenic avian influenza (HPAI) A(H5N1) viruses were tested with guinea pig sera negative for antibodies against all of these viruses as evaluated by hemagglutination-inhibition and microneutralization assays. In the presence of serum inhibitors, the infection by each virus was inhibited differently as measured by the amount of viral nucleoprotein produced in Madin-Darby canine kidney cells. The serum inhibitors inhibited seasonal influenza A(H3N2) virus the most, while the effect was less in seasonal influenza A(H1N1) and H1N1pdm viruses. The suppression by serum inhibitors could be reduced by heat inactivation or treatment with receptor destroying enzyme. In contrast, all H5N1 strains tested were resistant to serum inhibitors. To determine which structure (hemagglutinin (HA) and/or neuraminidase (NA)) on the virus particles that provided the resistance, reverse genetics (rg) was applied to construct chimeric recombinant viruses from A/Puerto Rico/8/1934(H1N1) (PR8) plasmid vectors. rgPR8-H5 HA and rgPR8-H5 HANA were resistant to serum inhibitors while rgPR8-H5 NA and PR8 A(H1N1) parental viruses were sensitive, suggesting that HA of HPAI H5N1 viruses bestowed viral resistance to serum inhibition. These results suggested that the ability to resist serum inhibition might enable the viremic H5N1 viruses to disseminate to distal end organs. The present study also analyzed for correlation between susceptibility to serum inhibitors and number of glycosylation sites present on the globular heads of HA and NA. H3N2 viruses, the subtype with highest susceptibility to serum inhibitors, harbored the highest number of glycosylation sites on the HA globular head. However, this positive correlation cannot be drawn for the other influenza subtypes

Conservative treatment for uncomplicated appendicitis in children:the CONTRACT feasibility study, including feasibility RCT

Background Whilst non-operative treatment is known to be effective for the treatment of uncomplicated acute appendicitis in children, comparative randomised trial data reporting important outcomes compared to appendicectomy are lacking.ObjectivesTo ascertain the feasibility of conducting a multi-centre randomised controlled trial (RCT) testing the effectiveness and cost-effectiveness of a non-operative treatment pathway compared to appendicectomy for the treatment of uncomplicated acute appendicitis in children.•DesignMixed methods study including: a feasibility RCT; embedded and parallel qualitative and survey studies; parallel health economic feasibility study; development of a core outcome set.Setting Three specialist NHS Paediatric Surgical Units in EnglandParticipants Children (aged 4-15 years) clinically diagnosed with uncomplicated acute appendicitis participated in the feasibility RCT. Children, their families, recruiting clinicians and other healthcare professionals involved in caring for children with appendicitis took part in the qualitative study. UK Specialist Paediatric Surgeons took part in the survey. Specialist Paediatric Surgeons, Adult General Surgeons who treat children, and children and young people who previously had appendicitis along with their families took part in the core outcomes set development.Interventions Participants in the feasibility RCT were randomised to a non-operative treatment pathway (broad-spectrum antibiotics and active observation) or appendicectomy.Main outcome measures Primary outcome measure was the proportion of eligible patients recruited to the feasibility trial.Data sourcesNHS casenotes, questionnaire responses, transcribed audio recordings of recruitment discussions and qualitative interviewsResults Overall, 50% (95%CI 40-59) of 115 eligible participants approached about the trial agreed to participate and were randomised. There was high acceptance of randomisation and good adherence to trial procedures and follow-up (follow rates of 89%, 85% and 85% at six weeks, three months and six months respectively). More participants had perforated appendicitis than had been anticipated.Qualitative work enabled us to: communicate about the trial effectively with patients and families; design and deliver bespoke training to optimise recruitment; and understand how to optimise design and delivery of a future trial.The health economic study, indicated that the main cost drivers are the ward stay cost and the cost of the operation, and has informed quality of life assessment methods for future work.A core outcome set for the treatment of uncomplicated acute appendicitis in children and young people was developed, containing 14 outcomes.There is adequate surgeon interest to justify proceeding to an effectiveness trial with 51% of those surveyed expressing a willingness to recruit with an unchanged trial protocol.LimitationsSince the feasibility RCT was only performed in three centres we cannot guarantee successful recruitment across a larger number of sites. However, our qualitative work has informed a bespoke training package to facilitate this. Although survey results suggest adequate clinician interest to make a larger trial possible, actual participation may differ, and equipoise may have moved over time.Conclusions A future effectiveness trial is feasible following limited additional preparation to establish appropriate outcome measures and case identification. We recommend a limited package of qualitative work be included to optimise recruitment at new centres in particular.Future work Prior to proceeding to an effectiveness trial we need to: develop a robust method for distinguishing children with uncomplicated acute appendicitis from those with more advanced appendicitis; reach agreement on a primary outcome measure and effect size that is acceptable to all stakeholder groups involved.Study registration ISRCTN15830435.Funding detailsNIHR HTA programm

CD11b+, Ly6G+ Cells Produce Type I Interferon and Exhibit Tissue Protective Properties Following Peripheral Virus Infection

The goal of the innate immune system is containment of a pathogen at the site of infection prior to the initiation of an effective adaptive immune response. However, effector mechanisms must be kept in check to combat the pathogen while simultaneously limiting undesirable destruction of tissue resulting from these actions. Here we demonstrate that innate immune effector cells contain a peripheral poxvirus infection, preventing systemic spread of the virus. These innate immune effector cells are comprised primarily of CD11b+Ly6C+Ly6G- monocytes that accumulate initially at the site of infection, and are then supplemented and eventually replaced by CD11b+Ly6C+Ly6G+ cells. The phenotype of the CD11b+Ly6C+Ly6G+ cells resembles neutrophils, but the infiltration of neutrophils typically occurs prior to, rather than following, accumulation of monocytes. Indeed, it appears that the CD11b+Ly6C+Ly6G+ cells that infiltrated the site of VACV infection in the ear are phenotypically distinct from the classical description of both neutrophils and monocyte/macrophages. We found that CD11b+Ly6C+Ly6G+ cells produce Type I interferons and large quantities of reactive oxygen species. We also observed that depletion of Ly6G+ cells results in a dramatic increase in tissue damage at the site of infection. Tissue damage is also increased in the absence of reactive oxygen species, although reactive oxygen species are typically thought to be damaging to tissue rather than protective. These data indicate the existence of a specialized population of CD11b+Ly6C+Ly6G+ cells that infiltrates a site of virus infection late and protects the infected tissue from immune-mediated damage via production of reactive oxygen species. Regulation of the action of this population of cells may provide an intervention to prevent innate immune-mediated tissue destruction

Evaluating implementation of a fire-prevention injury prevention briefing in children's centres: cluster randomised controlled trial

Background: Many developed countries have high mortality rates for fire-related deaths in children aged 0–14 years with steep social gradients. Evidence-based interventions to promote fire safety practices exist, but the impact of implementing a range of these interventions in children’s services has not been assessed. We developed an Injury Prevention Briefing (IPB), which brought together evidence about effective fire safety interventions and good practice in delivering interventions; plus training and facilitation to support its use and evaluated its implementation. Methods: We conducted a cluster randomised controlled trial, with integrated qualitative and cost-effectiveness nested studies, across four study sites in England involving children’s centres in disadvantaged areas; participants were staff and families attending those centres. Centres were stratified by study site and randomised within strata to one of three arms: IPB plus facilitation (IPB+), IPB only, usual care. IPB+ centres received initial training and facilitation at months 1, 3, and 8. Baseline data from children’s centres were collected between August 2011 and January 2012 and follow-up data were collected between June 2012 and June 2013. Parent baseline data were collected between January 2012 and May 2012 and follow-up data between May 2013 and September 2013. Data comprised baseline and 12 month parent- and staff-completed questionnaires, facilitation contact data, activity logs and staff interviews. The primary outcome was whether families had a plan for escaping from a house fire. Treatment arms were compared using multilevel models to account for clustering by children’s centre. Results: 1112 parents at 36 children’s centres participated. There was no significant effect of the intervention on families’ possession of plans for escaping from a house fire (adjusted odds ratio (AOR) IPB only vs. usual care: 0.93, 95%CI 0.58, 1.49; AOR IPB+ vs. usual care 1.41, 95%CI 0.91, 2.20). However, significantly more families in the intervention arms reported more behaviours for escaping from house fires (AOR IPB only vs. usual care: 2.56, 95%CI 01.38, 4.76; AOR IPB+ vs. usual care 1.78, 95%CI 1.01, 3.15). Conclusion: Our study demonstrated that children’s centres can deliver an injury prevention intervention to families in disadvantaged communities and achieve changes in home safety behaviours

The role of interfacial lipids in stabilizing membrane protein oligomers

Oligomerization of membrane proteins in response to lipid binding has a critical role in many cell-signalling pathways1 but is often difficult to define2 or predict3. Here we report the development of a mass spectrometry platform to determine simultaneously the presence of interfacial lipids and oligomeric stability and to uncover how lipids act as key regulators of membrane-protein association. Evaluation of oligomeric strength for a dataset of 125 α-helical oligomeric membrane proteins reveals an absence of interfacial lipids in the mass spectra of 12 membrane proteins with high oligomeric stability. For the bacterial homologue of the eukaryotic biogenic transporters (LeuT4, one of the proteins with the lowest oligomeric stability), we found a precise cohort of lipids within the dimer interface. Delipidation, mutation of lipid-binding sites or expression in cardiolipin-deficient Escherichia coli abrogated dimer formation. Molecular dynamics simulation revealed that cardiolipin acts as a bidentate ligand, bridging across subunits. Subsequently, we show that for the Vibrio splendidus sugar transporter SemiSWEET5, another protein with low oligomeric stability, cardiolipin shifts the equilibrium from monomer to functional dimer. We hypothesized that lipids are essential for dimerization of the Na+/H+ antiporter NhaA from E. coli, which has the lowest oligomeric strength, but not for the substantially more stable homologous Thermus thermophilus protein NapA. We found that lipid binding is obligatory for dimerization of NhaA, whereas NapA has adapted to form an interface that is stable without lipids. Overall, by correlating interfacial strength with the presence of interfacial lipids, we provide a rationale for understanding the role of lipids in both transient and stable interactions within a range of α-helical membrane proteins, including G-protein-coupled receptors

Diagnostic value of Pentraxin-3 in patients with sepsis and septic shock in accordance with latest sepsis-3 definitions

Background: Pentraxin-3 (PTX-3) is an acute-phase protein involved in inflammatory and infectious processes. This study assesses its diagnostic and prognostic value in patients with sepsis or septic shock in a medical intensive care unit (ICU). Methods: The study includes 213 ICU patients with clinical criteria of sepsis and septic shock. 77 donors served as controls. Plasma levels of PTX-3, procalcitonin (PCT) and interleukin-6 were measured on day 1, 3 and 8. Results: PTX-3 correlated with higher lactate levels as well as with APACHE II and SOFA scores (p = 0.0001). PTX-3 levels of patients with sepsis or septic shock were consistently significantly higher than in the control group (p ≤ 0.001). Plasma levels were able to discriminate sepsis and septic shock significantly on day 1, 3 and 8 (range of AUC 0.73–0.92, p = 0.0001). Uniform cut-off levels were defined at ≥5 ng/ml for at least sepsis, ≥9 ng/ml for septic shock (p = 0.0001). Conclusion: PTX-3 reveals diagnostic value for sepsis and septic shock during the first week of intensive care treatment, comparable to interleukin-6 according to latest Sepsis-3 definitions. Trial registration: NCT01535534. Registered 14.02.201

CONTRACT Study - CONservative TReatment of Appendicitis in Children (feasibility):study protocol for a randomised controlled Trial

BackgroundCurrently, the routine treatment for acute appendicitis in the United Kingdom is an appendicectomy. However, there is increasing scientific interest and research into non-operative treatment of appendicitis in adults and children. While a number of studies have investigated non-operative treatment of appendicitis in adults, this research cannot be applied to the paediatric population. Ultimately, we aim to perform a UK-based multicentre randomised controlled trial (RCT) to test the clinical and cost effectiveness of non-operative treatment of acute uncomplicated appendicitis in children, as compared with appendicectomy. First, we will undertake a feasibility study to assess the feasibility of performing such a trial.Methods/designThe study involves a feasibility RCT with a nested qualitative research to optimise recruitment as well as a health economic substudy. Children (aged 4–15 years inclusive) diagnosed with acute uncomplicated appendicitis that would normally be treated with an appendicectomy are eligible for the RCT. Exclusion criteria include clinical/radiological suspicion of perforated appendicitis, appendix mass or previous non-operative treatment of appendicitis. Participants will be randomised into one of two arms. Participants in the intervention arm are treated with antibiotics and regular clinical assessment to ensure clinical improvement. Participants in the control arm will receive appendicectomy. Randomisation will be minimised by age, sex, duration of symptoms and centre. Children and families who are approached for the RCT will be invited to participate in the embedded qualitative substudy, which includes recording of recruitment consultants and subsequent interviews with participants and non-participants and their families and recruiters. Analyses of these will inform interventions to optimise recruitment. The main study outcomes include recruitment rate (primary outcome), identification of strategies to optimise recruitment, performance of trial treatment pathways, clinical outcomes and safety of non-operative treatment. We have involved children, young people and parents in study design and delivery.DiscussionIn this study we will explore the feasibility of performing a full efficacy RCT comparing non-operative treatment with appendicectomy in children with acute uncomplicated appendicitis. Factors determining success of the present study include recruitment rate, safety of non-operative treatment and adequate interest in the future RCT. Ultimately this feasibility study will form the foundation of the main RCT and reinforce its design.Trial registrationISRCTN15830435. Registered on 8 February 2017