Treatment response and clinical event-free survival in autoimmune hepatitis: a Canadian multicentre cohort study

BACKGROUND & AIMS

We sought to identify predictors of outcome for people living with autoimmune hepatitis (AIH).

METHODS

We evaluated the clinical course of people with AIH across 11 Canadian centres. Biochemical changes were analysed using linear mixed-effect and logistic regression. Clinical outcome was dynamically modelled using time-varying Cox proportional hazard modelling and landmark analysis.

RESULTS

In 691 patients (median age 49 years, 75.4% female), with a median follow-up of 6 years (25th-75th percentile, 2.5-11), 118 clinical events occurred. Alanine aminotransferase (ALT) normalisation occurred in 63.8% of the cohort by 12-months. Older age at diagnosis (odd ratio [OR] 1.19, 95% CI 1.06-1.35) and female sex (OR 1.94, 95% CI 1.18-3.19) were associated with ALT normalisation at 6 months, whilst baseline cirrhosis status was associated with reduced chance of normalisation at 12 months (OR 0.52, 95% CI 0.33-0.82). Baseline total bilirubin, aminotransferases, and immunoglobulin G (IgG) values, as well as initial prednisone dose, did not predict average ALT reduction. At baseline, older age (hazard ratio [HR] 1.25, 95% CI 1.12-1.40), cirrhosis at diagnosis (HR 3.67, 95% CI 2.48-5.43), and elevated baseline total bilirubin (HR 1.36, 95% CI 1.17-1.58) increased risk of clinical events. Prolonged elevations in ALT (HR 1.07, 95% CI 1.00-1.13) and aspartate aminotransferase (HR 1.13, 95% CI 1.06-1.21), but not IgG (HR 1.01, 95% CI 0.95-1.07), were associated with higher risk of clinical events. Higher ALT at 6 months was associated with worse clinical event-free survival.

CONCLUSION

In people living with AIH, sustained elevated aminotransferase values, but not IgG, are associated with poorer long-term outcomes. Biochemical response and long-term survival are not associated with starting prednisone dose.

IMPACT AND IMPLICATIONS

Using clinical data from multiple Canadian liver clinics treating autoimmune hepatitis (AIH), we evaluate treatment response and clinical outcomes. For the first time, we apply mixed-effect and time-varying survival statistical methods to rigorously examine treatment response and the impact of fluctuating liver biochemistry on clinical event-free survival. Key to the study impact, our data is 'real-world', represents a diverse population across Canada, uses continuous measurements over follow-up, and our findings help inform risk stratification of patients. We provide evidence for treating clinicians, as well as those developing and evaluating new therapies, to seek evidence of good treatment response by keeping aminotransferase activity values within the reference range. Our results challenge the role of IgG as a marker of treatment response and if normalisation of IgG should remain an important part of the definition of biochemical remission. Our analysis further highlights that baseline markers of disease severity may not prognosticate early treatment response. Additionally, the initial prednisone dose may be less relevant for achieving aminotransferase normalisation. This is important for patients and treating clinicians given the relevance and importance of side-effects of treatment for patients.

Executive Summary of the 2023 Adult Position Development Conference of the International Society for Clinical Densitometry: DXA Reporting, Follow-up BMD Testing and Trabecular Bone Score Application and Reporting

After 15 months of preparation by task force chairs and teams, ISCD's 9th Position Development Conference (PDC) convened in Northbrook, IL, USA on March 28th and 29th, 2023 to approve new ISCD Official Positions in the topic areas of DXA Reporting, Follow-up BMD Testing and TBS Application and Reporting. Three teams of participants work to bring the PDC to fruition: the Steering Committee, Task Forces and Chairs, and the Expert Panel. To reach agreement on draft Official Positions, the PDC follows a scripted process with the UCLA/RAND Appropriateness Method (UCLA/RAM) as its foundation. Multiple rounds of data review, public debate and voting resulted in 32 new or modified Official Positions. Six companion position papers are also published along with this Executive Summary, serving as the detailed substantiation for the Official Positions. This Executive Summary reviews the personnel groups, activities and products of the 2023 PDC, with the entirety of the updated 2023 Official Positions presented in Appendix A. New Official Positions are highlighted in bold.

IL-6 Trans-Signaling Is Increased in Diabetes, Impacted by Glucolipotoxicity, and Associated With Liver Stiffness and Fibrosis in Fatty Liver Disease

Many people living with diabetes also have nonalcoholic fatty liver disease (NAFLD). Interleukin-6 (IL-6) is involved in both diseases, interacting with both membrane-bound (classical) and circulating (trans-signaling) soluble receptors. We investigated whether secretion of IL-6 trans-signaling coreceptors are altered in NAFLD by diabetes and whether this might associate with the severity of fatty liver disease. Secretion patterns were investigated with use of human hepatocyte, stellate, and monocyte cell lines. Associations with liver pathology were investigated in two patient cohorts: 1) biopsy-confirmed steatohepatitis and 2) class 3 obesity. We found that exposure of stellate cells to high glucose and palmitate increased IL-6 and soluble gp130 (sgp130) secretion. In line with this, plasma sgp130 in both patient cohorts positively correlated with HbA1c, and subjects with diabetes had higher circulating levels of IL-6 and trans-signaling coreceptors. Plasma sgp130 strongly correlated with liver stiffness and was significantly increased in subjects with F4 fibrosis stage. Monocyte activation was associated with reduced sIL-6R secretion. These data suggest that hyperglycemia and hyperlipidemia can directly impact IL-6 trans-signaling and that this may be linked to enhanced severity of NAFLD in patients with concomitant diabetes.

ARTICLE HIGHLIGHTS

IL-6 and its circulating coreceptor sgp130 are increased in people with fatty liver disease and steatohepatitis. High glucose and lipids stimulated IL-6 and sgp130 secretion from hepatic stellate cells. sgp130 levels correlated with HbA1c, and diabetes concurrent with steatohepatitis further increased circulating levels of all IL-6 trans-signaling mediators. Circulating sgp130 positively correlated with liver stiffness and hepatic fibrosis. Metabolic stress to liver associated with fatty liver disease might shift the balance of IL-6 classical versus trans-signaling, promoting liver fibrosis that is accelerated by diabetes.

Cost-effectiveness and willing-to-pay thresholds for vertebral augmentation of osteoporotic vertebral fractures, what are they based on: a systematic review

OBJECTIVE

Although there is substantial clinical evidence on the safety and effectiveness of vertebral augmentation for osteoporotic vertebral fractures, cost-effectiveness is less well known. The objective of this study is to provide a systematic review of cost-effectiveness studies and policy-based willingness-to-pay (WTP) thresholds for different vertebral augmentation (VA) procedures, vertebroplasty (VP) and balloon kyphoplasty (BK), for osteoporotic vertebral fractures (OVFs).

DESIGN

A systematic review targeting cost-effectiveness studies of VA procedures for OVFs.

DATA SOURCES

Six bibliographic databases were searched from inception up to May 2021.

ELIGIBILITY CRITERIA FOR STUDY SELECTION

Studies were eligible if meeting all predefined criteria: (1) VP or BK intervention, (2) OVFs and (3) cost-effectiveness study. Articles not written in English, abstracts, editorials, reviews and those reporting only cost data were excluded.

DATA EXTRACTION AND SYNTHESIS

Information was extracted on study characteristics, cost-effective estimates, summary decisions and payer WTP thresholds. Incremental cost-effective ratio (ICER) was the main outcome measure. Studies were summarised by a structured narrative synthesis organised by comparisons with conservative management (CM). Two independent reviewers assessed the quality (risk of bias) of the systematic review and cost-effectiveness studies by peer-reviewed checklists.

RESULTS

We identified 520 references through database searching and 501 were excluded as ineligible by titles and abstract. Ten reports were identified as eligible from 19 full-text reviews. ICER for VP versus CM evaluated as cost per quality-adjusted life-year (QALY) ranged from €22 685 (*US$33 395) in Netherlands to £-2240 (*US$-3273), a cost-saving in the UK. ICERs for BK versus CM ranged from £2706 (*US$3954) in UK to kr600 000 (*US$90 910) in Sweden. ICERs were within payer WTP thresholds for a QALY based on historical benchmarks.

CONCLUSIONS

Both VP and BK were judged cost-effective alternatives to CM for OVFs in economic studies and were within WTP thresholds in multiple healthcare settings.

Understanding How Post-COVID-19 Condition Affects Adults and Health Care Systems

Importance

Post-COVID-19 condition (PCC), also known as long COVID, encompasses the range of symptoms and sequelae that affect many people with prior SARS-CoV-2 infection. Understanding the functional, health, and economic effects of PCC is important in determining how health care systems may optimally deliver care to individuals with PCC.

Observations

A rapid review of the literature showed that PCC and the effects of hospitalization for severe and critical illness may limit a person's ability to perform day-to-day activities and employment, increase their risk of incident health conditions and use of primary and short-term health care services, and have a negative association with household financial stability. Care pathways that integrate primary care, rehabilitation services, and specialized assessment clinics are being developed to support the health care needs of people with PCC. However, comparative studies to determine optimal care models based on their effectiveness and costs remain limited. The effects of PCC are likely to have large-scale associations with health systems and economies and will require substantial investment in research, clinical care, and health policy to mitigate these effects.

Conclusions and Relevance

An accurate understanding of additional health care and economic needs at the individual and health system levels is critical to informing health care resource and policy planning, including identification of optimal care pathways to support people affected by PCC.

Pain Relief After Total Knee Arthroplasty with Intravenous and Periarticular Corticosteroid: A Randomized Controlled Trial

BACKGROUND

Total knee arthroplasty (TKA) is a cost-effective procedure, but it is also associated with substantial postoperative pain. The present study aimed to compare pain relief and functional recovery after TKA among groups that received intravenous corticosteroids, periarticular corticosteroids, or a combination of both.

METHODS

This randomized, double-blinded clinical trial in a local institution in Hong Kong recruited 178 patients who underwent primary unilateral TKA. Six of these patients were excluded because of changes in surgical technique; 4, because of their hepatitis B status; 2, because of a history of peptic ulcer; and 2, because they declined to participate in the study. Patients were randomized 1:1:1:1 to receive placebo (P), intravenous corticosteroids (IVS), periarticular corticosteroids (PAS), or a combination of intravenous and periarticular corticosteroids (IVSPAS).

RESULTS

The pain scores at rest were significantly lower in the IVSPAS group than in the P group over the first 48 hours (p = 0.034) and 72 hours (p = 0.043) postoperatively. The pain scores during movement were also significantly lower in the IVS and IVSPAS groups than in the P group over the first 24, 48, and 72 hours (p ≤ 0.023 for all). The flexion range of the operatively treated knee was significantly better in the IVSPAS group than in the P group on postoperative day 3 (p = 0.027). Quadriceps power was also greater in the IVSPAS group than in the P group on postoperative days 2 (p = 0.005) and 3 (p = 0.007). Patients in the IVSPAS group were able to walk significantly further than patients in the P group in the first 3 postoperative days (p ≤ 0.003). Patients in the IVSPAS group also had a higher score on the Elderly Mobility Scale than those in the P group (p = 0.036).

CONCLUSIONS

IVS and IVSPAS yielded similar pain relief, but IVSPAS yielded a larger number of rehabilitation parameters that were significantly better than those in the P group. This study provides new insights into pain management and postoperative rehabilitation following TKA.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

A44 A 1000 PATIENT CANADIAN NETWORK FOR AUTOIMMUNE LIVER DISEASE EVALUATION OF CLINICAL AND DEMOGRAPHIC PATTERNS OF AUTOIMMUNE HEPATITIS

Background

We sought to understand how the demographics of autoimmune hepatitis (AIH) have changed over time in Canada.

Purpose

Using a large multi-centre Canadian cohort of patients with AIH, we describe the trends in patient and disease characteristics at presentation across 30 years of clinical practice.

Method

Patients from the Canadian Network for Autoimmune Liver Disease with a confirmed diagnosis of AIH (simplified score ≥6) were included for analysis. Patients were grouped into five cohorts according to the year of diagnosis (i.e., <2000, 2000-2004, 2005-2009, 2010-2014, ≥2015). Patient demographics and baseline clinical and biochemistry features of disease activity were investigated using Chi-square tests and Kruskal-Wallis tests adjusted for multiple comparisons. Logistic and linear regression models with estimated means were utilized to further investigate relationships with time and to adjust for confounding.

Result(s)

1016 patients followed across 10 Canadian health centres with AIH were diagnosed between November 1965 and December 2021. Overall, 76.4% (n=776) of patients were female, and the median age at diagnosis was 46 years (IQR 28.2 - 58.3). Cirrhosis at presentation was seen in 20.6% of patients (n=209). The median age at diagnosis increased significantly from 31.8 years [IQR 17.9 - 46.8] pre-2000 to 54 years [IQR 9.0 - 95.2] after 2014 (p<0.001; Figure 1a). This effect of time persisted after adjusting for sex and cirrhosis status at diagnosis. Female sex and the presence of cirrhosis at diagnosis were factors independently associated with older age at presentation (p<0.0001).

The proportion of patients that presented with cirrhosis at diagnosis increased significantly over calendar time, from 13.7% (n=23) pre-2000 to 30.8% (n=69) after 2014 (p=0.003; Figure 1b). Male sex was independently associated with an increased odds of having cirrhosis at presentation (OR= 1.46, CI 1.02 - 2.07) and higher baseline ALT levels compared to females (p=0.036). The proportion of patients that identified as non-white ethnicity increased significantly from 15.2% (n= 24) pre-2000, to 32% (n= 86) after 2014 (p<0.001, Figure 1b). This effect of time on ethnicity was most pronounced after the year 2010 (OR= 2.32, CI 1.39 - 3.98) and persisted after adjusting for sex. There was no significant pattern of change in sex over calendar time.

Image

Conclusion(s)

In Canada, patients with AIH at presentation are now older, have more advanced disease, and are more ethnically diverse than when compared to 30 years ago.

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Disclosure of Interest

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Teneurin paralogues are able to localise synaptic sites driven by the intracellular domain and have the potential to form cis-heterodimers

Synaptic specificity during neurodevelopment is driven by combinatorial interactions between select cell adhesion molecules expressed at the synaptic membrane. These protein-protein interactions are important for instructing the correct connectivity and functionality of the nervous system. Teneurins are one family of synaptic adhesion molecules, highly conserved and widely expressed across interconnected areas during development. These type-II transmembrane glycoproteins are involved in regulating key neurodevelopmental processes during the establishment of neural connectivity. While four teneurin paralogues are found in vertebrates, their subcellular distribution within neurons and interaction between these different paralogues remains largely unexplored. Here we show, through fluorescently tagging teneurin paralogues, that true to their function as synaptic adhesion molecules, all four paralogues are found in a punctate manner and partially localised to synapses when overexpressed in neurons in vitro. Interestingly, each paralogue is differentially distributed across different pre- and post-synaptic sites. In organotypic cultures, Tenm3 is similarly localised to dendritic spines in CA1 neurons, particularly to spine attachment points. Furthermore, we show that the intracellular domain of teneurin plays an important role for synaptic localisation. Finally, while previous studies have shown that the extracellular domain of teneurins allows for active dimer formation and transsynaptic interactions, we find that all paralogues are able to form the full complement of homodimers and cis-heterodimers. This suggests that the combinatorial power to generate distinct molecular teneurin complexes underlying synaptic specificity is even higher than previously thought. The emerging link between teneurin with cancers and neurological disorders only serves to emphasise the importance of further elucidating the molecular mechanisms of teneurin function and their relation to human health and disease.

MoveStrong at Home: A feasibility study of a model for remote delivery of functional strength and balance training combined with nutrition education for older pre-frail and frail adults.

Exercise and nutrition interventions are often recommended for frailty; however, effective strategies are required for real-world implementation. Our primary aim was to assess the feasibility and acceptability of telephone and virtual delivery of MoveStrong, an 8-week exercise and nutrition program with a 4-week follow-up for older pre-frail and frail adults. A priori criteria for success included: recruitment (≥25/12 weeks), retention at follow-up (≥80%), and adherence to exercise and nutrition sessions (≥70%). We recruited community-dwelling Ontario residents; ≥60 years, ≥1 chronic condition, ≥1 FRAIL scale score. Participants received mailed materials, a personalized exercise program, eleven remote one-on-one training sessions with an exercise physiologist and three online dietitian-led nutrition education sessions. We completed exploratory analyses of secondary outcomes including physical function and dietary protein intake. Semi-structured interviews supported program evaluation. In total, 30 participants were enrolled. 28 (93%) participants completed program and follow-up assessments. Adherence to exercise and nutrition sessions (CI) was 84% (77-91%) and 82% (70-93%) respectively. At program end and follow-up [mean change (CI)], significant improvements were measured in 30-second chair stand test [3.50 (1.12–5.86), 4.54 (1.94–7.13) chair stands] and dietary protein intake [12.9 (5.7–20.0), 9.2 (0.4–18.1) g]. Overall, participants were satisfied with program delivery. Trial registration number: NCT04663685.

Ethnicity, disease severity, and survival in Canadian patients with primary biliary cholangitis

BACKGROUND AND AIMS

We investigated associations between ethnicity, survival, and disease severity in a diverse Canadian cohort of patients with primary biliary cholangitis (PBC).

APPROACH AND RESULTS

Patients with PBC were included from the Canadian Network for Autoimmune Liver Disease. Ethnicity was defined using a modified list adopted from Statistics Canada, and ethnicities with small samples were grouped. Clinical events were defined as liver decompensation, HCC, liver transplantation, or death. Clinical event-free and liver transplantation-free survival were analyzed using Cox regression. Trajectories of serum liver function tests were assessed over time using mixed-effects regression. Health-related quality of life was assessed using the Short Form 36, the PBC-40 questionnaire, and the 5-D Itch scale and analyzed using mixed-effects regression. The cohort included 1538 patients with PBC from six sites and was comprised of 82% White, 4.7% Indigenous, 5.5% East Asian, 2.6% South Asian, and 5.1% miscellaneous ethnicities. Indigenous patients were the only ethnic group with impaired liver transplant-free and event-free survival compared to White patients (HR, 3.66; 95% CI, 2.23-6.01; HR, 3.09; 95% CI, 1.94-4.92). Indigenous patients were more likely to have a clinical event before diagnosis (10%) than all other ethnic groups despite similar age at diagnosis. Indigenous patients presented with higher alkaline phosphatase, total bilirubin, and GLOBE scores than White patients; and these relative elevations persisted during follow-up.

CONCLUSIONS

Indigenous Canadians with PBC present with advanced disease and have worse long-term outcomes compared to White patients.

Cost-effectiveness studies of vertebral augmentation for osteoporotic vertebral fractures: a systematic review

BACKGROUND CONTEXT

Osteoporotic vertebral fractures (OVF) dramatically increase with age and are serious life altering adverse events for seniors resulting in increased rates of institutionalization, morbidity and mortality. Given the expanding population of the elderly and increasing prevalence of OVFs, cost-effective treatment strategies need to be considered. Percutaneous vertebral augmentation (VA) procedures such as vertebroplasty (VP) or balloon kyphoplasty (BK) are increasingly employed to treat painful vertebral fractures not responding to conservative management (CM) of bedrest and analgesia. Both VA procedures have been shown to be effective treatments for OVFs in multiple systematic reviews of randomized controlled trials. In this systematic review, analytical strategies, designs and results were compared for health economic studies evaluating cost-effectiveness of VA procedures, VP or BK for OVFs. Furthermore, assessments of quality (risk of bias) were conducted for the systematic review and the individual studies with peer-reviewed checklists recommended for cost-effectiveness studies.

PURPOSE

To provide an up-to-date systematic review of peer-reviewed studies evaluating cost-effectiveness of VA procedures, VP or KP for OVFs to support treatment and health care funding decisions.

STUDY DESIGN

This study is a systematic literature review and structured narrative synthesis.

STUDY SAMPLE

Peer reviewed health economic studies reporting cost-effectiveness for VA procedures, VP or BK for OVFs OUTCOME MEASURES: The following information extracted from the studies included: report country and year, study design, comparators, population, perspective, health valuations, costing sources and cost-effectiveness measures. For economic studies involving modeling, information was also extracted for model type, time horizon, key model drivers, and handling of uncertainty. Incremental cost-effectiveness ratio (ICER), the ratio of differences between comparator treatment groups in costs and health benefits, was considered the main cost-effectiveness measure.

METHODS

A systematic review was conducted of MEDLINE, EMBASE, CINAHL, ECONLIT, Cochrane Library and DARE databases up to the review date May 2021. Studies were reviewed for those reporting cost-effectiveness analyses on VA procedures including VP or BK for OVFs. Studies including only costs, abstracts, editorials, methodologies and reviews were not included. The selection of articles was reported in line with PRISMA guidance. A descriptive framework was developed to classify types of cost-effectiveness studies based on methodological differences and a structured narrative synthesis was used to summarize studies. Quality assessments were made with British Medical Journal checklist for individual cost-effectiveness studies and the CiCERO checklist for systematic reviews of cost-effectiveness studies.

RESULTS

In this systematic review, 520 references were identified through database searching and 501 were excluded as ineligible by titles and abstract based on prior eligibility criteria. From full-text reviews of 19 reports, ten were identified as eligible for the systematic review evaluating cost-effectiveness of VA procedures for OVFs. All references were published between 2008 and 2020. The ten cost-effectiveness studies, three for VP, three for BK and four for both VP and BK, all involved CM for OVFs as a treatment comparator. The studies involved different methods of economic analysis, modeling assumptions, cost and health valuations conducted in different health care setting over different time periods. A framework for the review outlines key features of cost-effectiveness study designs consisting of unmatched, matched, or randomized controls involving cost-effectiveness or cost-utility) analyses. Both VP and BK were cost-effective alternatives to CM for OVFs with earlier health gains and significantly shorter hospital stays. Cost-effectiveness estimates, ICERs, remained relatively stable and within willingness-to-pay thresholds under a range of sensitivity analyses. Comparisons between VP and BK were variable depending on modeling assumptions, but generally the procedures had similar health benefit gains with VP having lower acute procedural costs.

CONCLUSIONS

Both VP and BK, have been shown to be cost-effective alternatives to CM for osteoporotic vertebral fractures in diverse cost-effectiveness studies conducted in multiple health care settings. Trial-based cost-utility contributed the strongest evidence supporting cost-effectiveness determination for VP and BK for OVFs.

Frequent detection but lack of infectivity of SARS-CoV-2 RNA in pre-symptomatic, infected blood donor plasma

Respiratory viruses such as influenza do not typically cause viremia; however, SARS-CoV-2 has been detected in the blood of COVID-19 patients with mild and severe symptoms. Detection of SARS-CoV-2 in blood raises questions about its role in pathogenesis as well as transfusion safety concerns. Blood donor reports of symptoms or a diagnosis of COVID-19 after donation (post-donation information, PDI) preceded or coincided with increased general population COVID-19 mortality. Plasma samples from 2,250 blood donors who reported possible COVID-19–related PDI were tested for the presence of SARS-CoV-2 RNA. Detection of RNAemia peaked at 9%–15% of PDI donors in late 2020 to early 2021 and fell to approximately 4% after implementation of widespread vaccination in the population. RNAemic donors were 1.2- to 1.4-fold more likely to report cough or shortness of breath and 1.8-fold more likely to report change in taste or smell compared with infected donors without detectable RNAemia. No infectious virus was detected in plasma from RNAemic donors; inoculation of permissive cell lines produced less than 0.7–7 plaque-forming units (PFU)/mL and in susceptible mice less than 100 PFU/mL in RNA-positive plasma based on limits of detection in these models. These findings suggest that blood transfusions are highly unlikely to transmit SARS-CoV-2 infection.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Hmgcs2-mediated ketogenesis modulates high-fat diet-induced hepatosteatosis

OBJECTIVE

Aberrant ketogenesis is correlated with the degree of steatosis in NAFLD patients, and an inborn error of ketogenesis (mitochondrial HMG-CoA synthase deficiency) is commonly associated with the development of the fatty liver. Here we aimed to determine the impact of Hmgcs2-mediated ketogenesis and its modulations on the development and treatment of fatty liver disease.

METHODS

Loss- and gain-of-ketogenic function through in vivo and in vitro models, achieved by Hmgcs2 knockout and overexpression, respectively, were examined to investigate the role of ketogenesis in the hepatic lipid accumulation during neonatal development and the diet-induced NAFLD mouse model.

RESULTS

Ketogenic function was decreased in NAFLD mice with a reduction in Hmgcs2 expression. Mice lacking Hmgcs2 developed spontaneous fatty liver phenotype during postnatal development, which was rescued by a shift to a low-fat dietary composition via early weaning. Hmgcs2 heterozygous mice, which exhibited reduced ketogenic activity, were more susceptible to diet-induced NAFLD development, whereas HMGCS2 overexpression in NAFLD mice improved hepatosteatosis and glucose homeostasis.

CONCLUSIONS

Our study adds new knowledge to the field of ketone body metabolism and shows that Hmgcs2-mediated ketogenesis modulates hepatic lipid regulation under a fat-enriched nutritional environment. The regulation of hepatic ketogenesis may be a viable therapeutic strategy in the prevention and treatment of hepatosteatosis.

Total knee arthroplasty is safe for patients aged ≥80 years in Hong Kong

INTRODUCTION

Total knee arthroplasty (TKA) is an efficacious operation that improves pain and function in patients with knee arthritis. Because of the population ageing trend in Hong Kong, there is a need to determine the safety profile of TKA in older patients. This study examined the age of patients who underwent TKA in the past 10 years in Hong Kong; the aim was to investigate the mortality safety profile and clinical outcomes of TKA in patients aged ≥80 years.

METHODS

This study included all patients who underwent primary TKA in the Hospital Authority (HA) from 2010 to 2019. Incidences of 30-day, 90-day, and 1-year mortality were established. Clinical outcomes of patients aged ≥80 years in one cluster of HA hospitals were assessed.

RESULTS

Between 2010 and 2019, 25 040 TKA procedures were conducted in all HA hospitals; 2491 were conducted in patients aged ≥80 years. The median age at operation was higher during 2015-2019 than during 2010-2014 (70 vs 69 years; P<0.001); furthermore, an increase was observed in the proportion of patients aged ≥80 years at the time of operation. Incidences of 30-day, 90-day, and 1-year mortality were 0.156%, 0.35%, and 1.09%, respectively.

CONCLUSIONS

In this first study to examine the safety profile of TKA in older patients in Hong Kong, the mean age at the time of TKA and proportion of patients aged ≥80 years have steadily risen in the past decade. Even in older patients, TKA is a reasonably safe procedure.

Transcatheter mitral valve-in-valve implantation: a 10-year single center experience

Background

Transcatheter mitral valve-in-valve (TMVIV) appears a reasonable alternative to surgical redo mitral valve replacement in patients with degenerated mitral prosthesis and high surgical risk with favorable early and mid-terms outcomes. Long-term outcomes are limited by high mortality in a comorbid population.

Purpose

We aimed to evaluate early prosthesis hemodynamic performance and late clinical outcomes following TMVIV.

Methods

All patients who underwent TMVIV for degenerated surgical mitral bioprostheses from 2011 to 2020 in our center were included. Prospectively collected demographic, clinical, procedural, and imaging variables were analyzed. Clinical and echocardiographic outcomes were defined according to Mitral Valve Academic Research Consortium (MVARC) definitions and assessed at 30-day and at the latest follow-up available.

Results

A total of 67 patients were included; mean age 76.9±9.6 years, mean STS score 11.0±6.2%, 53.7% male (n=36). Mechanisms of bioprosthetic failure were mitral stenosis (n=32, 47.8%), mitral regurgitation (n=24, 35.8%), and mixed (n=11, 16.4%). Mean time from mitral valve surgery to TMVIV was 10.2±4.3 years. Access was mostly transapical (n=45; 67.2%), followed by transseptal (n=22; 32.8%). Following the first transseptal procedure in 2016; transseptal access accounted for the majority of procedures (22 of 37 cases, 59.4%).

Technical success was achieved in 65 patients (97.0%). Mean hospitalization was 9.2±10.0 days; shorter with the transseptal as opposed to the transapical approach (6.3±8.1 days versus 11.0±10.5 days, p=0.001). At 30-day echographic follow-up, mean mitral valve gradient was 7.3±2.7 and 1 patient (1.9%) had mitral regurgitation &gt;mild.

At 30-day follow-up, 3 patients had died (4.5%); due to left ventricular outflow tract obstruction (1), heart failure (1), and stroke (1). New pacemakers were required in 2 patients (3.0%) and pacemaker lead dislodgement occurred in 1 patient (1.5%), 4 patients (6.2%) were hospitalized for heart failure. At a median follow-up of 3.8 years [1.7–5.1], 29 patients had died (43.3%), valve thrombosis was found in 6 (8.9%) and endocarditis in 4 patients (6.2%). Mitral valve reintervention was performed in 4 patients (6.2%); redo TMVIV due to valve migration in 1 (1.9%), surgical valve replacement in 1 (1.9%), and delayed redilation with a non-compliant balloon due to underexpansion in 2 patients (3.8%).

Conclusion

TMVIV is associated with acceptable 30-day mitral valve hemodynamics. Long-term mortality remains high in this high-surgical risk comorbid group.

Funding Acknowledgement

Type of funding sources: None.

838 Pulmonary Embolectomy: Techniques and Outcomes from The Literature

Aim

Pulmonary embolectomy involves the surgical removal of a thrombus from the pulmonary tree, with the most popular approaches being surgical embolectomy (SE), percutaneous pulmonary embolectomy (PPE) and minimally invasive thoracotomy (MIT). The latter two new techniques are gradually increasing in popularity in the treatment of acute pulmonary embolism (PE) due to reduced recovery times. This study aims to evaluate and compare the clinical outcomes of the three aforementioned techniques in the treatment of acute PE.

Method

A literature review was performed with PUBMED to identify studies reporting these interventions. 79 papers were included, involving a total of 2445 patients. Patients’ baseline characteristics and perioperative status, inpatient mortality rates and complication rates of each intervention group were individually assessed and compared.

Results

Among all three interventions, SE studies demonstrated the highest in-patient mortality rate (20.8%). Patients receiving SE are also more likely to have pulmonary (2.8%) and other postoperative bleeding (7.4%). PPE patients are more likely to develop gastrointestinal bleeding and surgical site complications (4%). Scatter graph of the SE studies showed a declining trend of mortality rate over time (R²=0.50).

Conclusions

All three methods are effective in treating acute PE, while SE showed a trend of decreasing mortality over time. Further research on PPE and MIT is needed to define its place in the treatment of acute PE.

An international genome-wide meta-analysis of primary biliary cholangitis: Novel risk loci and candidate drugs

BACKGROUNDS & AIMS

Primary biliary cholangitis (PBC) is a chronic liver disease in which autoimmune destruction of the small intrahepatic bile ducts eventually leads to cirrhosis. Many patients have inadequate response to licensed medications, motivating the search for novel therapies. Previous genome-wide association studies (GWAS) and meta-analyses (GWMA) of PBC have identified numerous risk loci for this condition, providing insight into its aetiology. We undertook the largest GWMA of PBC to date, aiming to identify additional risk loci and prioritise candidate genes for in silico drug efficacy screening.

METHODS

We combined new and existing genotype data for 10,516 cases and 20,772 controls from 5 European and 2 East Asian cohorts.

RESULTS

We identified 56 genome-wide significant loci (20 novel) including 46 in European, 13 in Asian, and 41 in combined cohorts; and a 57th genome-wide significant locus (also novel) in conditional analysis of the European cohorts. Candidate genes at newly identified loci include FCRL3, INAVA, PRDM1, IRF7, CCR6, CD226, and IL12RB1, which each play key roles in immunity. Pathway analysis reiterated the likely importance of pattern recognition receptor and TNF signalling, JAK-STAT signalling, and differentiation of T helper (TH)1 and TH17 cells in the pathogenesis of this disease. Drug efficacy screening identified several medications predicted to be therapeutic in PBC, some of which are well-established in the treatment of other autoimmune disorders.

CONCLUSIONS

This study has identified additional risk loci for PBC, provided a hierarchy of agents that could be trialled in this condition, and emphasised the value of genetic and genomic approaches to drug discovery in complex disorders.

LAY SUMMARY

Primary biliary cholangitis (PBC) is a chronic liver disease that eventually leads to cirrhosis. In this study, we analysed genetic information from 10,516 people with PBC and 20,772 healthy individuals recruited in Canada, China, Italy, Japan, the UK, or the USA. We identified several genetic regions associated with PBC. Each of these regions contains several genes. For each region, we used diverse sources of evidence to help us choose the gene most likely to be involved in causing PBC. We used these 'candidate genes' to help us identify medications that are currently used for treatment of other conditions, which might also be useful for treatment of PBC.

Bayesian latent class analysis when the reference test is imperfect

Latent class analysis (LCA) has allowed epidemiologists to overcome the practical constraints faced by traditional diagnostic test evaluation methods, which require both a gold standard diagnostic test and ample numbers of appropriate reference samples. Over the past four decades, LCA methods have expanded to allow epidemiologists to evaluate diagnostic tests and estimate true prevalence using imperfect tests over a variety of complex data structures and scenarios, including during the emergence of novel infectious diseases. The objective of this review is to provide an overview of recent developments in LCA methods, as well as a practical guide to applying Bayesian LCA (BLCA) to the evaluation of diagnostic tests. Before conducting a BLCA, the suitability of BLCA for the pathogen of interest, the availability of appropriate samples, the number of diagnostic tests, and the structure of the data should be carefully considered. While formulating the model, the model's structure and specification of informative priors will affect the likelihood that useful inferences can be drawn. With the growing need for advanced analytical methods to evaluate diagnostic tests for newly emerging diseases, LCA is a promising field of research for both the veterinary and medical disciplines.

POS0417 EXOGENOUS CXCL5 RESTORES ENDOGENOUS BLOOD-TISSUE CHEMOKINE GRADIENT TO IMPROVE SURVIVAL IN MURINE LUPUS

Background:

Systemic lupus erythematosus (SLE) is a multi-organ autoimmune disease that is potentially fatal. There is an unmet need to improve current therapies. In patients with SLE, we observed that serum CXCL5 levels were significantly lower than healthy control subjects and negatively correlated with disease activity(1-9).

Objectives:

The aim of this study is to elucidate the effect of supplemental serum CXCL5 in abrogating the pathological processes of SLE.

Methods:

Ten doses of exogenous CXCL5 (3µg/kg) was administered to 16-week-old Faslpr mice weekly by intravenous injection. Mice were monitored for 10 weeks. Splenic immune profile was measured by flow cytometry. Circulating cytokine and immunoglobulin profile were detected by Luminex technology. Renal function was evaluated by urinary spot albumin creatinine ratio. In situ renal immune cell infiltration and complement 3 deposition were detected by Haematoxylin and Eosin (H&E) and immunohistochemistry staining. The molecular pathways involved were examined by RNA sequencing.

Results:

In Faslpr mice, intravenous administration of exogenous CXCL5 significantly improved mouse survival with concomitant reduction of autoantibody secretion, proteinuria, complement 3 deposition, neutrophil infiltration and lupus nephritis classes. Through evaluating the changes of immune profile, cytokine profile and molecular pathways, we found that intravenous CXCL5 reduced inflammation via an orchestral effect of regulating neutrophil trafficking and modulating helper T cell-mediated immune response. Pharmacokinetic and real-time Polymerase Chain Reaction studies further demonstrated that this orchestration was triggered by a cascade reaction - restoring vascular under-expressed CXCL5 by an exogenous stimulation, re-establishing the normal serum levels of endogenous CXCL5 and reverting the CXCL5 chemokine gradient between inflamed tissues and blood circulation.

Conclusion:

Managing the dysregulation of CXCL5 by exogenous supplement may provide a new option for SLE therapy.

References:

[1]Dufies M, Grytsai O, Ronco C, et al. New CXCR1/CXCR2 inhibitors represent an effective treatment for kidney or head and neck cancers sensitive or refractory to reference treatments. Theranostics. 2019;9(18):5332-5346. doi:10.7150/thno.34681

[2]Yildirim K, Colak E, Aktimur R, et al. Clinical Value of CXCL5 for Determining of Colorectal Cancer. Asian Pac J Cancer Prev. Sep 26 2018;19(9):2481-2484. doi:10.22034/apjcp.2018.19.9.2481

[3]Wu K, Yu S, Liu Q, Bai X, Zheng X. The clinical significance of CXCL5 in non-small cell lung cancer. Onco Targets Ther. 2017;10:5561-5573. doi:10.2147/ott.s148772

[4]Zhao J, Ou B, Han D, et al. Tumor-derived CXCL5 promotes human colorectal cancer metastasis through activation of the ERK/Elk-1/Snail and AKT/GSK3beta/beta-catenin pathways. Mol Cancer. Mar 29 2017;16(1):70. doi:10.1186/s12943-017-0629-4

[5]Han KQ, Han H, He XQ, et al. Chemokine CXCL1 may serve as a potential molecular target for hepatocellular carcinoma. Cancer Med. Oct 2016;5(10):2861-2871. doi:10.1002/cam4.843

[6]Pappa CA, Tsirakis G, Kanellou P, et al. Monitoring serum levels ELR+ CXC chemokines and the relationship between microvessel density and angiogenic growth factors in multiple myeloma. Cytokine. Dec 2011;56(3):616-20. doi:10.1016/j.cyto.2011.08.034

[7]Zhang L, Li H, Ge C, et al. CXCL3 contributes to CD133(+) CSCs maintenance and forms a positive feedback regulation loop with CD133 in HCC via Erk1/2 phosphorylation. Sci Rep. Jun 3 2016;6:27426. doi:10.1038/srep27426

[8]Matsubara J, Honda K, Ono M, et al. Reduced plasma level of CXC chemokine ligand 7 in patients with pancreatic cancer. Cancer Epidemiol Biomarkers Prev. Jan 2011;20(1):160-71. doi:10.1158/1055- 9965.epi-10-0397

[9]Ma Y, Ren Y, Dai ZJ, Wu CJ, Ji YH, Xu J. IL-6, IL-8 and TNF-alpha levels correlate with disease stage in breast cancer patients. Adv Clin Exp Med. May-Jun 2017;26(3):421-426. doi:10.17219/acem/62120

Disclosure of Interests:

None declared

Utility of the spinal instability neoplastic score to identify patients with Gorham-Stout disease requiring spine surgery

Background:

Gorham-Stout disease (GSD) is a rare syndrome presenting with progressive osteolysis which in the spine can lead to cord injury, instability, and deformity. Here, the early spine surgery may prevent catastrophic outcomes.

Case Description:

A 25-year-old male with GSD involving the T2 to T6 levels presented with acute traumatic kyphoscoliosis at T3 and T4 and left lower extremity paraparesis. The CT scan 4 weeks before this showed progressing osteolysis versus the CT 5 years ago. Unfortunately, the patient underwent delayed treatment resulting in permanent neurological sequelae. Surgery included a laminectomy and vertebrectomy of T3/T4 with instrumented fusion from T1-10. The use of the spinal instability neoplastic score (SINS) is a useful tool to prompt early referral to spine surgeons.

Conclusion:

We recommend using the SINS score in GSD patients who develop spinal lesions to prompt early referral for consideration of surgery.

Preoperative optimization to prevent periprosthetic joint infection in at-risk patients

Periprosthetic joint infection (PJI) remains an important complication with devastating consequences after total joint arthroplasties. With the increasing number of arthroplasties worldwide, the number of PJI will increase correspondingly with a significant economic burden to our healthcare system. It is likely impossible to completely eradicate PJI; hence, assessment and optimization of its risk factors to preventing such a disastrous complication will be the key. There are many strategies to prevent PJI in the preoperative, intraoperative, or postoperative phases. The preoperative assessment provides a unique opportunity to screen and diagnose underlying comorbidities and optimize modifiable risk factors before elective surgeries. In this review, we will focus on current literature in preoperative assessment of various modifiable risk factors and share the experience and practical approach in our institution in preoperative optimization to reduce PJI in total joint arthroplasties.

Single Topic Conference on Autoimmune Liver Disease from the Canadian Association for the Study of the Liver

Autoimmune liver disease (AILD) spans a spectrum of chronic disorders affecting the liver parenchyma and biliary system. Three main categories of AILD are autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), and primary sclerosing cholangitis (PSC). This review condenses the presentation and discussions of the Single Topic Conference (STC) on AILD that was held in Ottawa, Ontario, in November 2019. We cover generalities regarding disease presentation and clinical diagnosis; mechanistic themes; treatment paradigms; clinical trials, including approaches and challenges to new therapies; and looking beyond traditional disease boundaries. Although these diseases are considered autoimmune, the etiology and role of environmental triggers are poorly understood. AILDs are progressive and chronic conditions that affect survival and quality of life. Advances have been made in PBC treatment because second-line treatments are now available (obeticholic acid, bezafibrate); however, a significant proportion still present suboptimal response. AIH treatment has remained unchanged for several decades, and data suggest that fewer than 50% of patients achieve a complete response and as many as 80% develop treatment-related side effects. B-cell depletion therapy to treat AIH is in an early stage of development and has shown promising results. An effective treatment for PSC is urgently needed. Liver transplant remains the best option for patients who develop decompensated cirrhosis or hepatocellular carcinoma within specific criteria, but recurrent AILD might occur. Continued efforts are warranted to develop networks for AILD aimed at assessing geo-epidemiological, clinical, and biochemical differences to capture the new treatment era in Canada.

Geometrical predictors of small virtual neoLVOT size in functional mitral regurgitation

Background

LVOT obstruction is a potentially lethal complication of transcatheter mitral valve replacement (TMVR). An anticipated neoLVOT area of &lt;2cm2 is presumed to imply prohibitive risk. Measurement of the anticipated neoLVOT can be time consuming and requires specialist software to facilitate virtual valve implantation.

Purpose

To determine simple geometrical predictors of prohibitive neoLVOT size.

Methods

165 consecutive, non-calcific FMR patients referred to a transcatheter heart valve program were analysed. Segmentation of the mitral annulus and left heart geometry was performed using CT. Suitability for a default D-shaped TMVR was determined by proprietary annular inclusion criteria. Systolic neoLVOT area was determined via virtual valve implantation of the default TMVR.

Results

Sufficient image data for annular and neoLVOT suitability assessment was available in 152 patients. 105 patients (69%) were suitable for TMVR based on annular measurements. Of these, neoLVOT area was &gt;2cm2 in 88 (84%). Overall, compared to patients not suitable for TMVR (n=64), those suitable had larger ventricles with lower LVEF, and larger annuli (table 1). Using binomial logistic regression involving the variables within table 1, LVESD was the sole statistically significant variable to predict neoLVOT area of &lt;2cm2 (p=0.02). LVESD &lt;48mm had 82% sensitivity and 94% specificity for the presence of prohibitive neoLVOT (figure 1).

Conclusion

Smaller LVESD is a strong predictor of small neoLVOT, and hence LVOT obstruction post default D-shaped TMVR implantation. This simple measure may therefore be used to streamline patient selection for advanced pre-procedural imaging analysis.

Predicting NeoLVOT size &lt;2 cm2

Funding Acknowledgement

Type of funding source: None

Genomic Characterization of Cholangiocarcinoma in Primary Sclerosing Cholangitis Reveals Therapeutic Opportunities

BACKGROUND AND AIMS

Lifetime risk of biliary tract cancer (BTC) in primary sclerosing cholangitis (PSC) may exceed 20%, and BTC is currently the leading cause of death in patients with PSC. To open new avenues for management, we aimed to delineate clinically relevant genomic and pathological features of a large panel of PSC-associated BTC (PSC-BTC).

APPROACH AND RESULTS

We analyzed formalin-fixed, paraffin-embedded tumor tissue from 186 patients with PSC-BTC from 11 centers in eight countries with all anatomical locations included. We performed tumor DNA sequencing at 42 clinically relevant genetic loci to detect mutations, translocations, and copy number variations, along with histomorphological and immunohistochemical characterization. Regardless of the anatomical localization, PSC-BTC exhibited a uniform molecular and histological characteristic similar to extrahepatic cholangiocarcinoma. We detected a high frequency of genomic alterations typical of extrahepatic cholangiocarcinoma, such as TP53 (35.5%), KRAS (28.0%), CDKN2A (14.5%), and SMAD4 (11.3%), as well as potentially druggable mutations (e.g., HER2/ERBB2). We found a high frequency of nontypical/nonductal histomorphological subtypes (55.2%) and of the usually rare BTC precursor lesion, intraductal papillary neoplasia (18.3%).

CONCLUSIONS

Genomic alterations in PSC-BTC include a significant number of putative actionable therapeutic targets. Notably, PSC-BTC shows a distinct extrahepatic morpho-molecular phenotype, independent of the anatomical location of the tumor. These findings advance our understanding of PSC-associated cholangiocarcinogenesis and provide strong incentives for clinical trials to test genome-based personalized treatment strategies in PSC-BTC.

Universal haemoglobin A1c screening reveals high prevalence of dysglycaemia in patients undergoing total knee arthroplasty

INTRODUCTION

Diabetes mellitus is an established modifiable risk factor for periprosthetic joint infection (PJI). Haemoglobin A1c (HbA1c) is a glycaemic marker that correlates with diabetic complications and PJI. As diabetes and prediabetes are frequently asymptomatic, and there is increasing evidence to suggest a correlation between dysglycaemia and osteoarthritis, it is reasonable to provide HbA1c screening before total knee arthroplasty (TKA). The aim of the present study was to determine the prevalence of dysglycaemia in patients who underwent TKA and investigate whether HbA1c screening and optimisation of glycaemic control before TKA affects the incidence of PJI after TKA.

METHODS

Patients who underwent primary TKA before and after routine HbA1c screening was introduced in our unit were reviewed. Prediabetes and diabetes were defined according to the American Diabetes Association. Patients with HbA1c ≥7.5% were referred to an endocrinologist for optimisation of glycaemic control before TKA. The incidence PJI, defined according to the Musculoskeletal Infection Society criteria, was recorded.

RESULTS

A total of 729 patients (934 knees) had HbA1c screening before TKA. Of them, 17 (2.3%) and 184 (25.2%) patients had known prediabetes and diabetes, respectively, and 265 (36.4%) and 12 (1.6%) had undiagnosed prediabetes and diabetes, respectively. The incidence of PJI was significantly lower in all patients who received HbA1c screening compared with those who did not (0.2% vs 1.02%, P=0.027).

CONCLUSION

Screening for HbA1c before TKA provides a cost-effective opportunity to identify undiagnosed dysglycaemia. Patients identified as having dysglycaemia receive modified treatment, significantly reducing the rate of PJI when compared with historical controls.

AB0128 CXCL5 DAMPENS INFLAMMATION IN THE PRE-CLINICAL MODEL OF SYSTEMIC LUPUS ERYTHEMATOSUS VIA THE ORCHESTRAL EFFECT OF REGULATING NEUTROPHIL TRAFFICKING AND SUPPRESSING HELPER T CELL-MEDIATED IMMUNE RESPONSE

Background:

Patients with systemic lupus erythematosus (SLE) suffer from severe morbidity and mortality1-4, either from the disease itself or from side effects of immunosuppression5. Discovery of novel effective therapies with less toxicity is an urgent need.

Objectives:

The aim of this study is to elucidate the therapeutic potential and working mechanism of cytokine CXCL5 in lupus mice.

Methods:

Treatment with CXCL5, bone marrow (BM)-MSCs, standard of care (SOC) with combination of methylprednisolone and cyclophosphamide was given to 16-week-old Faslprmice. Mice were monitored for 10 weeks. Splenic immune cell subsets were measured by flow cytometry. Circulating cytokine and immunoglobulin were detected by Luminex technology. Renal function was evaluated by urinary spot albumin creatinine ratio. In situ renal immune cell infiltration and complement 3 deposition were detected by Haematoxylin and Eosin (H&E) staining and immunohistochemistry.

Results:

CXCL5 demonstrated consistent and potent immunosuppressive capacity in suppressing SLE with reduced autoantibody secretion, lymphoproliferation and preserved kidney function. With further exploration, we proved that CXCL5 reduced the proliferation of helper T cells (TH1 and TH2) in thein vitrofunctional assay. When we administrated CXCL5 to lupus mice, it promoted the proliferation of regulatory T cells and reduced the proliferation of TH17 cells, macrophages and neutrophils. Multiple proinflammatory cytokines including IL-2, IL-6, IL-12, IL-17A, KC/CXCL1, MIP-1β/CCL4 and TNF-α were also reduced. When combined with SOC, CXCL5 boosted its therapeutic effect and reduced the relevant indices of disease activity. When we correlated the effect of four different treatment groups (CXCL5, BM-MSCs, SOC, and CXCL5 plus SOC) on mice survival and target cell changes, we found that TH17 cells were the key effector cells involved in the pathogenesis of SLE.

Conclusion:

These findings demonstrated that CXCL5 dampens inflammation in the pre-clinical model of systemic lupus erythematosus via the orchestral effect of regulating neutrophil trafficking and suppressing helper T cell-mediated immune response. Administrating exogenous CXCL5 might be an attractive option to treat patients with lupus.

References:

[1]Ji S, Guo Q, Han Y, Tan G, Luo Y, Zeng F. Mesenchymal stem cell transplantation inhibits abnormal activation of Akt/GSK3beta signaling pathway in T cells from systemic lupus erythematosus mice.Cell Physiol Biochem.2012;29(5-6):705-712.

[2]Peng SL. Altered T and B lymphocyte signaling pathways in lupus.Autoimmun Rev.2009;8(3):179-183.

[3]Ferucci ED, Johnston JM, Gaddy JR, et al. Prevalence and incidence of systemic lupus erythematosus in a population-based registry of American Indian and Alaska Native people, 2007-2009.Arthritis Rheumatol.2014;66(9):2494-2502.

[4]Jakes RW, Bae SC, Louthrenoo W, Mok CC, Navarra SV, Kwon N. Systematic review of the epidemiology of systemic lupus erythematosus in the Asia-Pacific region: prevalence, incidence, clinical features, and mortality.Arthritis Care Res (Hoboken).2012;64(2):159-168.

[5]Sattwika PD, Mustafa R, Paramaiswari A, Herningtyas EH. Stem cells for lupus nephritis: a concise review of current knowledge.Lupus.2018;27(12):1881-1897.

Acknowledgments:

The work was supported by SMART II Centre Grant (NMRC/CG/M011/2017_SGH) and SingHealth Foundation (SHF/FG638P/2016).

Disclosure of Interests:

None declared

Blood transfusions in total knee arthroplasty: a retrospective analysis of a multimodal patient blood management programme

PURPOSE

Transfusion is associated with increased perioperative morbidity and mortality in patients undergoing total knee arthroplasty (TKA). Patient blood management (PBM) is an evidence-based approach to maintain blood mass via haemoglobin maintenance, haemostasis optimisation, and blood loss minimisation. The aim of the present study was to assess the effectiveness of a multimodal PBM approach in our centre.

METHODS

This was a single-centre retrospective study of patients who underwent primary TKA in Queen Mary Hospital in Hong Kong in 2013 or 2018, using data from the Clinical Data Analysis and Reporting System and a local joint registry database. Patient demographics, preoperative haemoglobin, length of stay, readmission, mean units of transfusion, postoperative prosthetic joint infection, and mortality data were compared between groups.

RESULTS

In total, 262 and 215 patients underwent primary TKA in 2013 and 2018, respectively. The mean transfusion rate significantly decreased after PBM implementation (2013: 31.3%; 2018: 1.9%, P<0.001); length of stay after TKA also significantly decreased (2013: 14.49±8.10 days; 2018: 8.77±10.14 days, P<0.001). However, there were no statistically significant differences in readmission, early prosthetic joint infection, or 90-day mortality rates between the two groups.

CONCLUSION

Our PBM programme effectively reduced the allogeneic blood transfusion rate in patients undergoing TKA in our institution. Thus, PBM should be considered in current TKA protocols to reduce rates of transfusions and related complications.

Prospective cohort study of influenza vaccine effectiveness among healthcare personnel in Lima, Peru: Estudio Vacuna de Influenza Peru, 2016-2018

Background

The Estudio Vacuna de Influenza Peru (VIP) cohort aims to describe the frequency of influenza virus infection, identify predictors of vaccine acceptance, examine the effects of repeated influenza vaccination on immunogenicity, and evaluate influenza vaccine effectiveness among HCP.

Methods

The VIP cohort prospectively followed HCP in Lima, Peru, during the 2016‐2018 influenza seasons; a fourth year is ongoing. Participants contribute blood samples before and after the influenza season and after influenza vaccination (for vaccinees). Weekly surveillance is conducted to identify acute respiratory or febrile illnesses (ARFI). When an ARFI is identified, participants self‐collect nasal swabs that are tested for influenza viruses by real‐time reverse transcriptase‐polymerase chain reaction. Influenza vaccination status and 5‐year vaccination history are ascertained. We analyzed recruitment and enrollment results for 2016‐2018 and surveillance participation for 2016‐2017.

Results

In the first 3 years of the cohort, VIP successfully contacted 92% of potential participants, enrolled 76% of eligible HCP, and retained >90% of participants across years. About half of participants are medical assistants (54%), and most provide “hands‐on” medical care (76%). Sixty‐nine percent and 52% of participants completed surveillance for >70% of weeks in years 1 and 2, respectively. Fewer weeks of completed surveillance was associated with older age (≥50 years), being a medical assistant, self‐rated health of fair or poor, and not receiving the influenza vaccine during the current season (P‐values < .05).

Conclusions

The VIP cohort provides an opportunity to address knowledge gaps about influenza virus infection, vaccination uptake, effectiveness and immunogenicity among HCP.

Transcriptomic analysis reveals the oncogenic role of S6K1 in hepatocellular carcinoma

The p70 ribosomal protein S6 kinase 1 (S6K1), a serine/threonine kinase, is commonly overexpressed in a variety of cancers. However, its expression level and functional roles in hepatocellular carcinoma (HCC), which ranks as the third leading cause of cancer-related death worldwide, is still largely unknown. In the current report, we show the in vivo and in vitro overexpression of S6K1 in HCC. In the functional analysis, we demonstrate that S6K1 is required for the proliferation and colony formation abilities in HCC. By using comparative transcriptomic analysis followed by gene ontology enrichment analysis and Ingenuity Pathway Analysis, we find that the depletion of S6K1 can elevate the expression of a cluster of apoptotic genes, tumor suppressor genes and immune responsive genes. Moreover, the knockdown of S6K1 is predicted to reduce the tumorigenicity of HCC through the regulation of hubs of genes including STAT1, HDAC4, CEBPA and ONECUT1. In conclusion, we demonstrate the oncogenic role of S6K1 in HCC, suggesting the possible use of S6K1 as a therapeutic target for HCC treatment.

Expression and Roles of Teneurins in Zebrafish

The teneurins, also known as Ten-m/Odz, are highly conserved type II transmembrane glycoproteins widely expressed throughout the nervous system. Functioning as dimers, these large cell-surface adhesion proteins play a key role in regulating neurodevelopmental processes such as axon targeting, synaptogenesis and neuronal wiring. Synaptic specificity is driven by molecular interactions, which can occur either in a trans-homophilic manner between teneurins or through a trans-heterophilic interaction across the synaptic cleft between teneurins and other cell-adhesion molecules, such as latrophilins. The significance of teneurins interactions during development is reflected in the widespread expression pattern of the four existing paralogs across interconnected regions of the nervous system, which we demonstrate here via in situ hybridization and the generation of transgenic BAC reporter lines in zebrafish. Focusing on the visual system, we will also highlight the recent developments that have been made in furthering our understanding of teneurin interactions and their functionality, including the instructive role of teneurin-3 in specifying the functional wiring of distinct amacrine and retinal ganglion cells in the vertebrate visual system underlying a particular functionality. Based on the distinct expression pattern of all teneurins in different retinal cells, it is conceivable that the combination of different teneurins is crucial for the generation of discrete visual circuits. Finally, mutations in all four human teneurin genes have been linked to several types of neurodevelopmental disorders. The opportunity therefore arises that findings about the roles of zebrafish teneurins or their orthologs in other species shed light on the molecular mechanisms in the etiology of such human disorders.

Abstract P2-12-01: Dose- and exposure-response relationship and biomarker correlation analysis in breast tumors from patients treated with capivasertib, an AKT inhibitor, in the STAKT randomized, placebo controlled pre-surgical study

Background: Capivasertib (AZD5363), an AKT1,2,3 inhibitor, significantly improved progression-free and overall survival when added to paclitaxel in triple negative breast cancer (BC) patients (Schmid et al. ASCO 2018). We have previously reported in STAKT, robust target inhibition at 480mg BD versus placebo, including significant decreases in the primary biomarkers (PBs) - Ki67, pPRAS40 & pGSK3β - in primary BCs (Robertson et al. SABCS 2017). We now report the dose- and exposure-response relationship of capivasertib and the correlation between primary and secondary (pAKT, pS6, nuclear FOXO3a) tumor biomarkers.

Design: STAKT was a two-stage, double blind, randomized, placebo controlled 'window-of-opportunity' trial in newly diagnosed ER+ BC patients. Stage 1 assessed capivasertib at a dose of 480mg BD p.o. versus placebo. Stage 2 assessed capivasertib at two lower doses 360mg and 240mg BD. Tumor biopsies were taken prior to 1st dose and after 4.5 days of dosing. Evaluable patients (who required pre-defined minimum baseline PD values for PBs) included placebo (n=11), capivasertib at 480mg (n=17), 360mg (n=5) and 240mg (n=6). Blood samples for pharmacokinetic (PK) studies were scheduled at pre-dose; 2, 4, optional 6 & 8 hrs post first dose on Day 1; ˜2-4 h post last dose on Day 5 (before biopsy). The % change from baseline for PBs were evaluated against the following exposure variables (placebo=0): i) Dose, ii) Observed Cmax Day 1 (˜2h post-dose), iii) Observed plasma concentration on Day 5, iv) Model-predicted plasma concentration Day 5 at time of biopsy, and v) Model-predicted AUC on Day 5. Spearman correlation coefficient measured the strength and direction of association between biomarkers.

Results:

· Significant mean reductions in % change from baseline were observed for the PBs pGSK3β (-39%; p&lt;0.006), pPRAS40 (-50%; p&lt;0.0001) and Ki67 (-23%; p=0.052) at 480mg versus placebo. At 360mg and 240mg, mean % changes from baseline in pGSK3β were -27% and -9%, respectively; in pPRAS40 -45% and -28%, respectively; and in Ki67 0% and +22%, respectively.

· Dose-response relationships for individual % change from baseline could be described by an Emax model for all PBs. Overall, the correlation to PK exposure (observed or predicted) was similar to the correlation to dose.

· Correlation coefficient analyses between biomarkers at capivasertib 480mg BD identified- i) Positive correlations for pGSK3β with Ki67 (ρ = 0.52, p-value &lt; 0.05) & with pS6 (ρ = 0.54, p-value&lt;0.05); ii) Negative correlations between FOXO3a and Ki67 (ρ = -0.75, p-value&lt;0.001) pGSK3β (ρ = -0.71, p-value&lt;0.001) & also pS6 (ρ = -0.61, p-value&lt;0.001).Correlation coefficients for lower doses are not robust due to small sample size in these groups.

Conclusions

· Capivasertib caused dose- and concentration- dependent effects on biomarkers after only 4.5 days.

· Significant changes in the PBs were demonstrated at 480 mg BD. Biomarker changes was observed at 360mg and 240mg BD, but statistical analysis was limited by the small sample size at lower doses.

· Correlation between a number of tumor biomarkers (relative changes) were identified for capivasertib 480mg BD.

Citation Format: Gee J, Coleman RE, Cheung KL, Evans A, Holcombe C, Skene A, Rea D, Ahmed S, Jahan A, Horgan K, Rauchhaus P, Littleford R, Finlay P, Cheung A, Cullberg M, de Bruin E, Foxley A, Koulai L, Pass M, Schiavon G, Rugman P, Deb R, Robertson JFR. Dose- and exposure-response relationship and biomarker correlation analysis in breast tumors from patients treated with capivasertib, an AKT inhibitor, in the STAKT randomized, placebo controlled pre-surgical study [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-12-01.

Metabolomic Profiling of Portal Blood and Bile Reveals Metabolic Signatures of Primary Sclerosing Cholangitis

Primary sclerosing cholangitis (PSC) is a pathogenically complex, chronic, fibroinflammatory disorder of the bile ducts without known etiology or effective pharmacotherapy. Emerging in vitro and in vivo evidence support fundamental pathophysiologic mechanisms in PSC centered on enterohepatic circulation. To date, no studies have specifically interrogated the chemical footprint of enterohepatic circulation in PSC. Herein, we evaluated the metabolome and lipidome of portal venous blood and bile obtained at the time of liver transplantation in patients with PSC (n = 7) as compared to individuals with noncholestatic, end-stage liver disease (viral, metabolic, etc. (disease control, DC, n = 19)) and to nondisease controls (NC, living donors, n = 12). Global metabolomic and lipidomic profiling was performed on serum derived from portal venous blood (portal serum) and bile using ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and differential mobility spectroscopy-mass spectroscopy (DMS-MS; complex lipid platform). The Mann–Whitney U test was used to identify metabolites that significantly differed between groups. Principal-component analysis (PCA) showed significant separation of both PSC and DC from NC for both portal serum and bile. Metabolite set enrichment analysis of portal serum and bile demonstrated that the liver-disease cohorts (PSC and DC) exhibited similar enrichment in several metabolite categories compared to NC. Interestingly, the bile in PSC was uniquely enriched for dipeptide and polyamine metabolites. Finally, analysis of patient-matched portal serum and biliary metabolome revealed that these biological fluids were more homogeneous in PSC than in DC or NC, suggesting aberrant bile formation and enterohepatic circulation. In summary, PSC and DC patients exhibited alterations in several metabolites in portal serum and bile, while PSC patients exhibited a unique bile metabolome. These specific alterations in PSC are amenable to hypothesis testing and, potentially, therapeutic pharmacologic manipulation.