A protocol to establish cell line models from rare pediatric solid tumors

Pediatric cell line models are important for basic and translational research. However, their establishment has been hampered by low success rates and the lack of a unified approach. Here, we present a protocol to establish pediatric cancer cell lines from rare childhood tumors. We describe the requirements for successful establishment, including an optimized dissociation technique, and the appropriate media conditions necessary for several types of rare but lethal forms of childhood cancers. For complete details on the use and execution of this protocol, please refer to Sun et al.1.

Generation and multi-dimensional profiling of a childhood cancer cell line atlas defines new therapeutic opportunities

Pediatric solid and central nervous system tumors are the leading cause of cancer-related death among children. Identifying new targeted therapies necessitates the use of pediatric cancer models that faithfully recapitulate the patient's disease. However, the generation and characterization of pediatric cancer models has significantly lagged behind adult cancers, underscoring the urgent need to develop pediatric-focused cell line resources. Herein, we establish a single-site collection of 261 cell lines, including 224 pediatric cell lines representing 18 distinct extracranial and brain childhood tumor types. We subjected 182 cell lines to multi-omics analyses (DNA sequencing, RNA sequencing, DNA methylation), and in parallel performed pharmacological and genetic CRISPR-Cas9 loss-of-function screens to identify pediatric-specific treatment opportunities and biomarkers. Our work provides insight into specific pathway vulnerabilities in molecularly defined pediatric tumor classes and uncovers biomarker-linked therapeutic opportunities of clinical relevance. Cell line data and resources are provided in an open access portal.

The global syndemic of metabolic diseases in the young adult population: a consortium from the Global Burden of Disease 2000-2019

Funding Acknowledgements

Type of funding sources: None.

Background

A large proportion of premature deaths are related to metabolic diseases in the young adult population. We examined the global trends and mortality of metabolic diseases using estimates from the Global Burden of Diseases, Injuries and Risk Factors Study (GBD) 2019 in individuals aged below 40 years.

Methods

From 2000-2019, global estimates of prevalence, deaths, and disability-adjusted life years (DALYs) were described for metabolic diseases (type 2 diabetes mellitus [T2DM], hypertension, non-alcoholic fatty liver disease [NAFLD]). Global estimates were limited to mortality and DALYs for risk factors (hyperlipidemia and obesity). Subgroup analyses were performed based on sex, geographical regions and Socio-Demographic Index (SDI). Age-standardized prevalence, death, and DALYs were presented per 100,000 population with 95% uncertainty intervals (UI).

Findings

The prevalence for all metabolic diseases increased from 2000-2019, with the most pronounced increase in males and high SDI countries. In 2019, the highest age-standardised death rates were observed in hypertension (133·88 [121·25-155·73]; males, 160·13 [138·91-180·79]; females, 119·66 [102·33-136·86]), followed by obesity (62·59 [39·92-89·13]; males, 66·55 [39·76-97·21]; females, 58·14 [38·53-81·39]), hyperlipidemia (56·51 [41·83-73·62]; males, 67·33 [50·78-86·43]; females, 46·50 [32·70-62·38]), T2DM (18·49 [17·18-19·66]; males, 19·94 [18·50-21·32]; females, 17·30 [15·62-18·70]) and NAFLD (2·09 [1·61-2·60]; males, 2·38 [1·82-3·02]; females, 1·82 [1·41-2·27]). Similarly, obesity (1932·54 [1276·61-2639·74]) had the highest age-standardised DALYs, followed by hypertension (2885·57 [2580·75-3201·05]), hyperlipidemia (1207·15 [975·07-1461·11]), T2DM (801·55 [670·58-954·43]) and NAFLD (53·33 [40·73-68·29]). Mortality rates decreased over time in hyperlipidemia (-60%), hypertension (-47%), NAFLD (-31%) and T2DM (-20%), but not in obesity (107% increase). The highest metabolic-related mortality was observed in the Eastern Mediterranean and low SDI countries.

Conclusion

The growing prevalence of metabolic diseases, increasing obesity-related mortality trends, and the sex-regional-socioeconomic disparities evident in young adulthood, present the concerning global burden of metabolic diseases now and in the years ahead.

Global burden of metabolic diseases: data from Global Burden of Disease 2000-2019. A cosortium of metabolic disease

Funding Acknowledgements

Type of funding sources: None.

Background

The growing prevalence of metabolic diseases is a major concern. We sought to examine the global trends and mortality of metabolic diseases using estimates from the Global Burden of Diseases, Injuries and Risk Factors Study (GBD) 2019.

Methods

Global estimates of prevalence, deaths, and disability-adjusted life year (DALYs) from 2000-2019 were examined for metabolic diseases (type 2 diabetes mellitus [T2DM], hypertension, and nonalcoholic fatty liver disease [NAFLD]). For metabolic risk factors (hyperlipidemia and obesity), estimates were limited to mortality and DALYs. Death rates was compared across sex, World Health Organisation regions and Socio-demographic Index (SDI) quintiles. Age-standardised prevalence and death rates were presented per 100,000 population with 95% uncertainty intervals (UI).

Findings

From 2000 to 2019, prevalence rates increased for all metabolic diseases, with the most pronounced increase in high SDI countries. In 2019, the mean (95%UI) age-standardised prevalence per 100,000 population was estimated to be 15,023 (13,493-16,764) for NAFLD, 5,283 (4,864–5,720) for T2DM and 234 (171-313) for hypertension. The highest age-standardised death rates were observed in obesity (62·59 [39·92-89·13]; males, 66·55 [39·76-97·21]; females. 58·14 [38·53-81·39]), followed by hyperlipidemia (56·51 [41·83-73·62]; males, 67·33 [50·78-86·43]; females, 46·50 [32·70-62·38]), T2DM (18·49 [17·18-19·66], males, 67·33 [50·78-86·43]; females, 46·50 [32·70-62·38]), hypertension (15·16 [11·20-16·75]; males, 14·95 [10·32-16·75]; females, 15·05 [11·51-17·09]) and NAFLD (2·09 [1·61-2·60]; males, 2·38 [1·82-3·02]; females, 1·82 [1·41-2·27]). Mortality rates decreased over time in hyperlipidemia (-154%), hypertension (-52%) and NAFLD (-52%), but not in T2DM and obesity. The highest mortality for metabolic diseases was found in Eastern Mediterranean, and low to low-middle SDI countries.

Conclusion

The global prevalence of metabolic diseases has risen over the past two decades regardless of SDI. Attention is needed to address the unchanging mortality rates attributed to metabolic disease and the regional, socioeconomic, and sex disparities in mortality from metabolic disease.

Metabolic associated fatty liver disease increases risk of adverse events after acute coronary syndrome

 

Metabolic Associated Fatty Liver Disease (MAFLD) was recently introduced as an alternative definition for fatty liver, that has been linked to an increased risk of systemic end-organ damage. However, current studies have not examined the impact of MAFLD on patients presenting with acute coronary syndrome (ACS). Here, we present a retrospective analysis on the short and long-term outcomes of ACS patients with MAFLD.

Methods

A retrospective analysis was conducted in a tertiary care centre. Hepatic steatosis and fibrosis was examined with hepatic steatosis index and fibrosis-4 (FIB-4) index. The primary and secondary outcomes of the analysis were long term all-cause mortality, and in-hospital all-cause mortality, stroke, heart failure and cardiogenic shock respectively. Adjusted analysis was conducted for primary and secondary outcomes with covariates including age, sex, race, type of ACS and previous myocardial infarction.

Results

A total of 5770 patients were included in the analysis, and 21% of ACS patients had concomitant MAFLD. MAFLD resulted in a 23% increase in long-term all-cause mortality compared to non-MAFLD (HR: 1.230, CI: 1.065 to 1.420, p=0.005). MAFLD increased the risk of in-hospital mortality, stroke, heart failure and cardiogenic shock compared to non-MAFLD. A sensitivity analysis conducted based on MAFLD with advance fibrosis, chronic kidney disease and diabetes also demonstrated significantly increased effect size magnitude of all-cause mortality, compared to non-MAFLD.

Conclusion

MAFLD represents an encapsulation of metabolism dysregulation and has been associated with increased risk of systematic disease. The present study shows that MAFLD is associated with significantly increased adverse prognostic outcomes after ACS compared to non-MAFLD. An increase in awareness of MAFLD is required beyond the field of hepatology for improvements in multidisciplinary care and management.

Funding Acknowledgement

Type of funding sources: None.

A 10-year cohort on prognostic outcomes in patients presenting with acute myocardial infarction complicated by cardiogenic shock and/or cardiac arrest

Background

Cardiogenic shock (CS) and cardiac arrest (CA) complicating acute myocardial infarction (AMI) portend unfavourable outcomes. This study examined the prognosis of patients presenting with AMI complicated by CS and/or CA.

Methods

Consecutive patients presented with AMI to a percutaneous coronary intervention-capable tertiary institution between 2011 and 2021 were studied. Patients were stratified based on the presence or absence of CS (CS+ or CS−) and CA (CA+ or CA−). The primary outcome was 30-day cardiovascular-related mortality. Subgroup analyses based on AMI-type and sex were conducted. Kaplan-Meier curves for cardiovascular-related mortality based on the AMI-type and sex were constructed.

Results

The study included 11,608 AMI patients, 283 of whom had CS+/CA+, 1,068 had CS+/CA−, 54 had CS−/CA+ and 10,203 had CS−/CA−. Cardiovascular-related mortality was significantly higher for CS+/CA+ (57.6%), followed by CS+/CA− (41.6%), CS−/CA+ (20.4%) and CS−/CA− (2.4%). Kaplan-Meier curves demonstrated CS+/CA+ group had the highest mortality (HR=36.26; 95% CI: 29.71–44.25, p<0.001), followed by CS+/CA− (HR=21.59; 95% CI: 18.47–25.24, p<0.001) and CS−/CA+ (HR=9.18; 95% CI: 5.02–16.80, p<0.001), with CS−/CA− as the reference. Those with NSTEMI had consistently higher cardiovascular-related mortality rates than their STEMI counterparts for all groups, apart from the CS+/CA+ group. The sex-specific analysis demonstrated that the survival curves for females with CS+/CA+, CS+/CA− and CS−/CA+ converged, whilst the survival curves for males diverged over time. The multivariable Cox regression revealed the presence of CS and CA are independent predictors of cardiovascular-related mortality, but not NSTEMI, when adjusted for age, gender, diabetes, left ventricular ejection fraction, chronic renal failure, and culprit vessel.

Conclusions

AMI associated with CA and CS portends the least favourable survival, followed by those with CS or CA alone. Excess mortality was observed in the traditionally perceived lower-risk groups, particularly in women. This calls for increased awareness amongst clinicians when managing this subset of high-risk patients.

Funding Acknowledgement

Type of funding sources: None.

Prognostically distinct phenotypes of metabolic health beyond obesity in aortic stenosis

Background

Whilst current evidence are in favour of metabolic health and non-obesity in the reduction of incident cardiovascular disease, little is known regarding the prognosis across the metabolic phenotypes once cardiovascular disease occurs. This study examined the prognosis of patients with significant aortic stenosis (AS) based on the presence of metabolic health and obesity.

Methods

This retrospective cohort on consecutive patients presenting with moderate-to-severe AS to a tertiary hospital between 2010 and 2015. Patients were allocated into 4 groups based on obesity and metabolic health: metabolically healthy obese (MHO), metabolically healthy non-obese (MHNO), metabolically unhealthy obese (MUO) and metabolically unhealthy non-obese (MUNO). Metabolic health was defined in accordance to Program Adult Treatment Panel III criteria. The primary outcome was all-cause mortality. Cox regression examined independent associations between mortality and metabolic phenotypes, adjusting for aortic valve area, ejection fraction, age, sex, chronic kidney disease and AVR as a time-dependent covariate.

Results

Of 727 patients, the majority (51.6%) were MUNO, followed by MUO (32.7%), MHNO (11.4%), and MHO (4.3%). MHNO had the highest mortality (43.0%), followed by the MUNO (37.5%), MUO (30.0%) and MHO (6.9%) groups (p=0.001). Compared to MHNO, MHO (HR 0.159, 95% CI 0.038–0.668, p=0.012) and MUO (HR 0.614, 95% CI 0.403–0.937, p=0.024) were independently associated with lower all-cause mortality rates, after adjusting for confounders. In obese patients, metabolic health had favourable survival compared to metabolically unhealthy (p=0.015), but this protective impact of metabolic health was not observed in overweight or normal weight individuals. Obesity had favourable survival compared to overweight and normal weight, in both metabolically health (p=0.002) and unhealthy (p=0.007) patients,

Conclusion

MHO patients with AS have the most favourable prognosis whilst the seemingly healthy MHNO group had the worst survival. There should be a paradigm shift towards prioritising metabolic health rather than weight reduction in patients with significant AS.

Funding Acknowledgement

Type of funding sources: None.

The prognostic outcomes of acute myocardial infarction stratified according to metabolic health and obesity status

Background

There has been emerging evidence on the favourable cardiovascular disease incidence in non-obese subjects with healthy metabolism. However, little is known regarding the prognosis across the metabolic phenotypes once cardiovascular disease is established. This study examines the prognosis of patients with acute myocardial infarction (AMI) stratified according to metabolic health and obesity status.

Methods

A retrospective study conducted in a tertiary hospital between 2014–2021. Consecutive patients with AMI were allocated into 4 groups based on metabolic and obesity profile: metabolically healthy obesity (MHO), metabolically healthy non-obesity (MHNO), metabolically unhealthy obesity (MUO) and metabolically unhealthy non-obesity (MUNO). The primary outcome was all-cause mortality. Cox regression examined the independent association between mortality and metabolic phenotypes, adjusting for age, sex, AMI type and ejection fraction.

Results

A total of 9958 patients were studied with majority (68.5%) in the MUNO group, followed by MUO (25.1%), MHNO (5.6%), and MHO (0.8%). MHO patients had lowest mortality (7.4%), followed by MHNO (9.7%), MUO (19.2%) and MUNO (22.6%, p<0.001). Relative to MHNO, MUO (HR 1.610, 95% CI 1.198–2.163, p=0.002) and MUNO (HR 1.383, 95% CI 1.043–1.835, p=0.024) had significantly higher mortality risk, but not MHO (HR 1.514, 95% CI 0.649–3.534, p=0.337), after adjusting for confounders. Kaplan-Meier curves showed favourable survival in metabolically healthy groups with clear divergence from metabolically unhealthy groups (p<0.001). There were stepwise increments in mortality with increasing number of metabolic risk factors regardless of obesity status (p<0.001). Favourable survival was observed in overweight and obese versus normal weight patients regardless of metabolic health.

Conclusion

Metabolically healthy AMI patients had favourable prognosis compared to metabolically unhealthy patients. The obesity paradox was observed in the AMI cohort, but the beneficial effects of obesity appeared not as pronounced in magnitude as in metabolically healthy groups.

Funding Acknowledgement

Type of funding sources: None.

MODL-17. The Childhood Brain Cancer Cell Line Atlas: A Resource for Biomarker Identification and Therapeutic Development

Cell lines represent the most versatile and widely used models of cancer and, as such, are critical for identifying and advancing new therapies. Strikingly, there is a significant gap in both the number of childhood brain cancer cell lines and their characterisation compared to their adult counterparts. To address this inequity, we established a childhood brain cancer cell line atlas (publicly available at vicpcc.org.au/dashboard) encompassing over 180 childhood CNS-derived cell lines, representing 20 tumour types and 11 molecular subtypes. Cell lines are characterized by whole genome, RNA-sequencing, phospho- and total proteomics, DNA methylation and ATAC-seq analyses. Multi-omic factor analysis revealed distinct lineage-specified classification of our cell line cohort. In parallel, high throughput drug and CRISPR/Cas9 screens were conducted to map the functional dependencies in over 70 childhood CNS cell lines, including 47 paediatric high grade glioma models. These screens identified both lineage and molecular-subtype specific genetic and drug dependencies, underscoring the utility of this wide-scale approach. Machine based learning approaches to predict genotype-phenotype correlations uncovered distinct paediatric-specific biomarkers of growth dependency, highlighting the unique genetic wiring underlying paediatric CNS tumours. Finally, by integrating functional, molecular and drug profiles of paediatric CNS cell lines, we construct a system to prioritize investigation of novel therapeutic target-biomarkers pairs in specific CNS tumour types.

A network meta-analysis on the vasomodulators for portopulmonary hypertension

Background

In patients with portopulmonary hypertension (PoPH) who are eligible and awaiting liver transplant, guidelines recommend lowering pulmonary pressures with vasomodulators as a bridge to transplant. However, efficacy of each vasomodulator class as a bridge to transplant remains unknown.

Purpose

This review compares the use of endothelin receptor antagonists (ERA), phosphodiesterase type-5 inhibitors (PDE5-I), prostacyclin (PC) and combination therapy in its pulmonary pressure-lowering effects and pre-transplant mortality in this strictly selected subset of patients.

Methods

A search conducted on Medline and Embase on articles relating to vasomodulator use in PoPH for pulmonary pressure-lowering effects and mortality. Network analysis was conducted to summarize the evidence. Surface under the cumulative ranking curve (SUCRA) was used to rank treatments.

Results

Ten studies with 180 patients were included. SUCRA analysis demonstrated largest mean pulmonary artery pressure (mPAP) and pulmonary vascular resistance (PVR) lowering effects in ERA and combination therapy, followed by PDE5-I and PC. mPAP-lowering effects were largest in ERA (MD −19.440, CI: −62.280 to 23.400) and combination therapy (MD −18.223, CI: −29.677 to −6.770) when compared to PDE5-I (table 1). Pre-transplant mortality were comparable between ERA, PDE5-I and combination therapy. Both ERA (RR:0.349. CI: 0.137–0.891) and PDE5-I (RR: 0.279, CI: 0.091–0.854) had significantly lower mortality than PC (table 2).

Conclusion

This meta-analysis provides preliminary evidence that ERA have shown larger pulmonary pressure-lowering effects than PDE5-I in PoPH patients who were eligible for LT. Both ERA and PDE5-I have comparable mortality outcomes, with unfavorable outcomes in PC users.

Funding Acknowledgement

Type of funding sources: None.

Characterisation of patients with concomitant cancer in significant aortic stenosis

Background

There is an increasing incidence of cancer worldwide, while aortic stenosis is the most common valvular heart disease. However, management of aortic stenosis (AS) in patients with cancer remains poorly understood. The presence of concomitant AS in patients with cancer may confer added morbidity and mortality.

Methods

We studied 727 consecutive patients with index echocardiographic diagnosis of moderate to severe aortic stenosis (aortic valve area <1.5cm2). These patients were divided in patients with or without concomitant cancer. Baseline clinical and echocardiographic parameters were compared by appropriate univariate analyses. Kaplan-Meier curves were constructed to compare mortality, admissions for congestive cardiac failure and aortic valve replacement between the groups.

Results

Eighty-five (11.7%) patients had concomitant cancer with moderate to severe AS. Of those, 45 (52.9%) had active cancer. The group with cancer was similar in terms of age, body mass index, clinical comorbidities compared to the group without cancer. AS severity and echocardiographic profile was similar except for a lower LVIDd (43.6±12.0 vs 47.4±8.9mm, p<0.001), and LV mass index (103.1±43.2 vs 116.6±41.5, p=0.005). There was higher mortality in the cancer group (log-rank 17.6, p<0.001), similar incidence of admissions for cardiac failure (log-rank 0.58, p=0.446) and a lower incidence of aortic valve replacement (log-rank 3.96, p=0.047) compared to the group without cancer. Patients with AS who received cancer treatment did better than those that did not receive cancer treatment.

Conclusion

Concomitant cancer in patients with moderate to severe AS was associated with increased mortality, and a lower incidence of aortic valve replacement. Further studies are warranted to investigate the role of valve replacement in patients with cancer.

Figure 1

Funding Acknowledgement

Type of funding source: None

Co-existing aortic regurgitation associated with adverse clinical outcomes in patients with moderate to severe aortic stenosis

Background

Aortic regurgitation (AR) is a common comorbidity in patients with aortic stenosis (AS), but co-existing AR has often been an exclusion criterion from major clinical trials. The impact of co-existing AR on the natural history of AS has not been well-described.

Purpose

We compared clinical outcomes in patients with moderate to severe AS with or without co-existing AR.

Methods

Consecutive patients (n=1188) with index echocardiographic diagnosis of moderate to severe AS (AVA <1.5cm2) were studied. They were divided into those with co-existing AR (at least moderate severity) and those without. Adverse composite clinical outcomes were defined as either mortality or admissions for congestive cardiac failure on subsequent follow-up for at least five years. Appropriate univariate and multivariable analyses were employed to compare the two groups.

Results

There were 88 patients (7.4%) with co-existing AR and AS. These patients did not differ significantly in age, but had lower body mass index (22.9±3.8 vs 25.3±5.1 kg/m2). They also had lower diastolic blood pressure (68.7±10.7 vs 72.2±12.3 mmHg), larger end-diastolic volume index (68.8±18.8 vs 60.4±17.8 ml/m2) and left ventricular mass index (118.6±36.4 vs 108.9±33.1 g/m2). The prevalence of cardiovascular risk factors did not differ significantly between the groups. Co-existing AR was associated with adverse outcomes (log-rank 4.20, p=0.040). On multivariable Cox-regression, co-existing AR remained independently associated with adverse outcomes (hazard ratio 1.51, 95% CI 1.13–2.02) after adjusting for age, AS severity and left ventricular ejection fraction.

Conclusion

In patients with AS, co-existing AR was associated with a distinct echocardiographic profile and adverse outcomes.

Funding Acknowledgement

Type of funding source: None

Clinical and echocardiographic outcomes of patients with moderate to severe aortic stenosis and preserved, mid-range and reduced ejection fraction

Background

Left ventricular ejection fraction (EF) plays an important role in risk stratifying and guiding therapy for patients with aortic stenosis (AS). This study aims to describe the clinical and echocardiographic outcomes of AS patients with preserved (ASpEF), mid-range (ASmrEF) and reduced (ASrEF) EF.

Methods

713 consecutive patients with index echocardiographic diagnosis of moderate-severe AS (aortic valve area <1.5cm2) were allocated according to the EF into three groups: ASrEF (EF<40%), ASmrEF (EF 40–50%), and ASpEF (EF>50%). The study outcomes were defined as 5-year all-cause mortality, heart failure admissions, and aortic valve replacement (AVR).

Results

In comparison to patients with ASpEF, those with ASrEF were more frequently male, and systolic blood pressure was significantly lower on enrolment (p<0.001). Diabetes, ischemic heart disease and atrial fibrillation were more commonly seen in the ASrEF and ASmrEF groups, compared to ASpEF group. All-cause mortality rates were 30.5% for ASpEF, 50.8% for ASmrEF, 55.0% for ASrEF groups (p<0.001). Increased rates of heart failure admissions were seen in the ASmrEF and ASrEF groups (30.5% and 33.9%, respectively, vs. 14.9% in ASpEF group). Patients with ASrEF had significantly higher rates of AVR as compared to those in the ASmrEF and ASpEF groups (p=0.032).

Conclusion

Echocardiographic and clinical outcomes of ASmrEF patients resembled those of ASrEF more closely than the ASpEF patients. Stratifying AS patients according to the different EF groups may improve risk assessment and treatment strategies.

Figure 1

Funding Acknowledgement

Type of funding source: None

THU0260 GLUCOCORTICOID DOSE IS AN INDEPENDENT PREDICTOR OF MORTALITY IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS HOSPITALIZED FOR INFECTION

Background:

Infection is an important cause of mortality and morbidity in patients with systemic lupus erythematosus (SLE) and a common cause for hospitalization. Glucocorticoids (GC) may contribute to increased mortality.

Objectives:

We performed a 10-year retrospective study of SLE patients hospitalized for infection, and the clinical predictors of mortality, especially GC dose, in these patients.

Methods:

Diagnosis codes for SLE were obtained from the electronic medical records for hospitalized patients from 2005 to 2015. Chart review was performed to ascertain the indication for hospitalization. The first hospitalization for infection (if any) was used as the index admission. Demographic and clinical characteristics, infection site and immunosuppressive drugs over the past month were abstracted. Multivariable logistic regression was used to determine predictors of all-cause mortality at 1 year.

Results:

Diagnosis codes were obtained for 768 unique SLE patients with 3660 hospitalization episodes over 10 years, of which 689 had a physician diagnosis of SLE on chart review. Of these, 250 (36%) had an index admission for infection. 243/250 (97.2%) fulfilled the ACR 1997 criteria for SLE and were studied further (Figure 1). Median (IQR) age was 45.1 (37.3, 56) years, 86% were female, 72% were Chinese, median (IQR) disease duration was 9 (4, 17) years. 53 (21.8%) patients had chronic kidney disease (CKD), 34 (14%) had diabetes mellitus (DM) and 12 (4.9%) had cancer. 231 (95.1%) patients were on immunosuppressive drugs and 210 (86.4%) were on GC. The median (IQR) GC dose was 8 (5, 15) mg oral prednisolone equivalent per day. The median (IQR) Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score was 4 (1, 10). The most common organism was Escherichia coli, followed by Staphylococcus aureus and Salmonella enteritidis. The respiratory tract was the most common site of infection. 27.9% of patients who had blood cultures performed had bacteremia. There were 11 (4.5%) ICU admissions, 6 (2.5%) patients died in hospital and 1-year all-cause mortality was 13 (5.3%). SLEDAI had only a weak positive correlation with GC dose [R2= 0.039/Pearson’s correlation = 0.197, p = 0.004)] (Figure 2). Increased age (odds ratio (OR) 1.07, 95% CI 1.02-1.12, p = 0.005), average daily GC dose (OR 1.05, 95% CI 1.02-1.09, p = 0.002), bone infections (OR 42.24, 95% CI 2.76-646.8, p = 0.007) and CKD (OR 4.78, 95% CI 1.06-21.54, p = 0.04) were independent predictors of 1-year mortality, after adjusting for gender, SLEDAI, DM, and cancer (Table 1).

Table 1.

Predictors of mortality

FactorsUnivariableOdds Ratio(95% CI)P-valueMultivariableOdds Ratio(95% CI)P-valueAge at admission (years)1.04 (1.005, 1.07)0.021.07 (1.02,1.12)0.005Average dose of oral prednisolone (mg/day)1.04 (1.01, 1.06)0.0061.05 (1.02,1.09)0.002Gender (female vs male)3.52 (1.22, 10.12)0.020.37 (0.07, 2.10)0.26Disease duration > 10 years1.27 (0.49, 3.33)0.62Positive blood culture0.54 (0.17, 1.75)0.30Site of infectionGastrointestinal1 (reference)0.170.06Respiratory1.09 (0.28, 4.29)0.900.71 (0.09, 5.57)0.74Renal0.27 (0.03, 2.48)0.250.44 (0.03, 5.94)0.54Skin, Gynecological, Other0.94 (0.25, 3.51)0.931.04 (0.16, 6.74)0.96Bone11.75 (1.29, 107.1)0.0342.24 (2.76, 646.8)0.007Primary Bacteremia0.00 (0.00, 0.00)0.990.00 (0.00, 0.00)0.99SLEDAI score ≥41.23 (0.47, 3.21)0.660.65 (0.15, 2.74)0.56Diabetes Mellitus0.46 (0.14, 1.50)0.201.61 (0.31, 8.3)0.57Chronic Kidney Disease0.30 (0.11, 0.78)0.014.78 (1.06, 21.54)0.04Cancer0.18 (0.04, 0.77)0.023.52 (0.25, 48.82)0.35

Conclusion:

Higher dose of oral GC was an independent predictor of mortality, even after adjusting for disease activity. It is important to prescribe the minimum effective dose of GC in SLE patients with infection, especially in older patients with CKD and bone infection.

Disclosure of Interests:

Thurston Yan Jia Heng: None declared, Nicholas Chew: None declared, Kexin Amanda Choo: None declared, Aisha Lateef: None declared, Manjari Lahiri Grant/research support from: Manjari Lahiri is the site principal investigator for the Singapore National Biologics Register, which is a multi-pharmaceutical funded register, in which industry sponsors provide support through the Chapter of Rheumatologists, Singapore. Dr Lahiri does not personally receive any remuneration.

Methanol outbreak: a Malaysian tertiary hospital experience

Introduction

Methanol poisoning usually occurs in a cluster and initial diagnosis can be challenging. Mortality is high without immediate interventions. This paper describes a methanol poisoning outbreak and difficulties in managing a large number of patients with limited resources.

Methodology

A retrospective analysis of a methanol poisoning outbreak in September 2018 was performed, describing patients who presented to a major tertiary referral centre.

Result

A total of 31 patients were received over the period of 9 days. Thirty of them were males with a mean age of 32 years old. They were mostly foreigners. From the 31 patients, 19.3% were dead on arrival, 3.2% died in the emergency department and 38.7% survived and discharged. The overall mortality rate was 61.3%. Out of the 12 patients who survived, two patients had toxic optic neuropathy, and one patient had uveitis. The rest of the survivors did not have any long-term complications.

Osmolar gap and lactate had strong correlations with patient’s mortality. Serum pH, bicarbonate, lactate, potassium, anion gap, osmolar gap and measured serum osmolarity between the alive and dead patients were significant. Post-mortem findings of the brain were unremarkable.

Conclusion

The mortality rate was higher, and the morbidity includes permanent visual impairment and severe neurological sequelae. Language barrier, severity of illness, late presentation, unavailability of intravenous ethanol and fomipezole and delayed dialysis may have been the contributing factors. Patient was managed based on clinical presentation. Laboratory parameters showed difference in median between group that survived and succumbed for pH, serum bicarbonate, lactate, potassium and osmolar and anion gap. Management of methanol toxicity outbreak in resource-limited area will benefit from a well-designed guideline that is adaptable to the locality.

P910An Asian perspective on left ventricular outflow tract cut-offs and the resulting discrepancy in severity grading of aortic stenosis

Objectives

Inconsistencies in grading of aortic stenosis (AS) severity have been reported based on measurement of left ventricular outflow tract diameter (LVOTd), but this remains to be studied in an Asian population. We investigated consistency of grading AS severity at various LVOTd, and subsequently postulated alternative cut-offs for more consistent grading of AS severity.

Methods

350 consecutive patients with index echocardiographic diagnosis of severe AS were divided them into three groups based on LVOTd: “small” (<20mm), “average” (20–22mm), “large” (>22mm). In each group, the consistency of flow-dependent (transaortic mean pressure gradient (MG)) and flow-independent parameters (AVA) were used for classification of AS severity.

Results

Of 350 patients, 51.7% had small LVOTd, while 30.8% and 17.5% had average and large LVOTd respectively. Consistent grading by LVOTd based on AVA and MG, was seen in 33.7% of patients with small, 47.6% with average, 57.7% with large LVOTd. When the hypothetical AVA cut-off of 0.9cm2 was used, consistent grading improved to 38.0% in small, 56.5% in average and 70% in large LVOTd. At an AVA cut-off of 0.8cm2, there was further incremental improvement in the small LVOTd group to 54.1% (p<0.05).

Table 1. Consistent grading by LVOTd based on current guidelines Small LVOTd (<20mm, n=181) Average LVOTd (20–22mm, n=108) Large LVOTd (>22mm, n=61) Consistent grading AVA < cut-off MG >40 Consistency (%) Consistent grading AVA < cut-off MG >40 Consistency (%) Consistent grading AVA < cut-off MG >40 Consistency (%) n=61 33.7 n=51 47.6 n=35 57.7 n=69 38 n=61 56.5 n=43 70* n=98 54.1*+ n=70 65.1* n=43 70.8* *p-value <0.05 when compared with AVA cut-off 0.8cm2 for each LVOTd category; +p-value <0.05 when compared with AVA cut-off 0.9cm2 for each LVOTd category.

Figure 1

Conclusion

Current severe AS guidelines are most consistent with those in the large LVOTd group. However, the majority of the study's Asian population is in the small LVOTd group, which is the group most susceptible to discrepancy in AS grading. Improved consistency in echocardiographic grading may be attained with a lower AVA cut-off in this Asian cohort.

P3366Increased left ventricular remodelling index in paradoxical low-flow severe aortic stenosis with preserved left ventricular ejection fraction compared to normal-flow

Background

Left Ventricular Remodelling Index (LVRI) has been demonstrated to be able to reliably discriminate between an athlete's heart and pathological LV remodelling. Patients with paradoxical low-flow severe aortic stenosis (LF AS) despite preserved left ventricular ejection fraction (LVEF) are a distinct group from normal-flow (NF) with poorer prognosis, more concentric hypertrophy and smaller LV cavities.

Purpose

We compared LVRI in LF compared to NF AS and examined clinical outcomes.

Methods

We studied consecutive patients with index echocardiographic diagnosis of severe AS (aortic valve area<1cm2) with preserved LVEF (>50%). LVRI was determined by the ratio of LV mass to the end-diastolic volume.

Results

Of the 450 patients studied, 149 (33.1%) were LF. There were no significant differences in baseline clinical profile of patients between LF and NF. LVRI was significantly higher in patients with LF compared to NF (2.27±0.68 vs 1.85±0.53 g/ml, p<0.001). Patients with high LVRI (>1.56 g/ml) had poorer clinical outcomes in terms of mortality (log-rank 9.18, p=0.002) and admissions for cardiac failure (log-rank 7.61, p=0.006).

Low-flow (n=149) Normal-flow (n=301) Mean difference/Odds Ratio (95% CI) p-value Age (years) 73.5 (±12.8) 71.0 (±13.1) 2.5 (−0.1 to 5.1) 0.053 Body Mass Index (g/m2) 24.6 (±5.6) 24.7 (±5.3) −0.1 (−1.2 to 1.1) 0.877 Gender (male) 49 (32.9%) 125 (41.5%) 0.7 (0.5 to 1.1) 0.076 Hypertension 100 (67.1%) 195 (64.8%) 1.1 (0.7 to 1.7) 0.624 Diabetes 57 (38.3%) 100 (33.2%) 1.2 (0.8 to 1.9) 0.295 Hyperlipidaemia 79 (53.0%) 147 (49.0%) 1.2 (0.8 to 1.7) 0.425 End-diastolic volume (ml) 72.3 (±18.9) 112.6 (±26.3) −40.2 (−44.9 to −35.5) <0.001 Left ventricular ejection fraction (%) 66.0 (±7.9) 67.4 (±7.1) −1.4 (−2.9 to 0.2) 0.077 Left ventricular mass index (g/m2) 99.7 (±33.0) 126.8 (±37.4) −27.2 (−34.8 to −19.6) <0.001 Transaortic mean pressure gradient (mmHg) 32.2 (±17.4) 37.1 (±19.9) −4.9 (−8.6 to −1.1) 0.011 Aortic valve area (cm2) 0.78 (±0.16) 0.79 (±0.17) 0.1 (−0.2 to 0.1) 0.635 Stroke volume index (ml/m2) 28.6 (±5.6) 46.9 (±9.8) −18.3 (−20.0 to −16.6) <0.001 Left ventricular remodelling index (LVRI, g/ml) 2.27 (±0.68) 1.85 (±0.53) 0.42 (0.31 to 0.54) <0.001

LVRI in LF versus NF AS

Conclusion

Pathological LV remodelling as evidenced by increased LVRI was more common in LF compared to NF AS. Patients with increased LVRI also had worse clinical outcomes.

Acknowledgement/Funding

None

STAT-3 regulation of CXCR4 is necessary for the prenylflavonoid Icaritin to enhance mesenchymal stem cell proliferation, migration and osteogenic differentiation

Mesenchymal stem cell (MSC) dysfunction has been implicated in the pathogenesis of osteoporosis. MSCs derived from osteoporotic subjects demonstrate significant impairment in proliferation, adhesion and chemotaxis, and osteogenic differentiation, leading to reduced functional bone-forming osteoblasts and ultimately nett bone loss and osteoporosis. Epimedium herbs and its active compound Icaritin (ICT) have been used in Chinese ethnopharmacology for the treatment of metabolic bone diseases. Using an in-vitro cell culture model, we investigated the benefits of ICT treatment in enhancing MSC proliferation, migration and osteogenic differentiation, and provide novel data to describe its mechanism of action. ICT enhances MSC proliferation, chemotaxis to stromal cell-derived factor-1 (SDF-1) and osteogenic differentiation through the activation of signal transduction activator transcription factor 3 (STAT-3), with a consequential up-regulation in the expression and activity of cysteine (C)-X-C motif chemokine receptor 4 (CXCR4). These findings provide a strong basis for future clinical studies to confirm the therapeutic potential of ICT for the prevention and treatment of osteoporosis and fragility fractures.

Helicobacter pylori Type IV Secretion System and Its Adhesin Subunit, CagL, Mediate Potent Inflammatory Responses in Primary Human Endothelial Cells

The Gram-negative bacterium, Helicobacter pylori, causes chronic gastritis, peptic ulcers, and gastric cancer in humans. Although the gastric epithelium is the primary site of H. pylori colonization, H. pylori can gain access to deeper tissues. Concurring with this notion, H. pylori has been found in the vicinity of endothelial cells in gastric submucosa. Endothelial cells play crucial roles in innate immune response, wound healing and tumorigenesis. This study examines the molecular mechanisms by which H. pylori interacts with and triggers inflammatory responses in endothelial cells. We observed that H. pylori infection of primary human endothelial cells stimulated secretion of the key inflammatory cytokines, interleukin-6 (IL-6) and interleukin-8 (IL-8). In particular, IL-8, a potent chemokine and angiogenic factor, was secreted by H. pylori-infected endothelial cells to levels ~10- to 20-fold higher than that typically observed in H. pylori-infected gastric epithelial cells. These inflammatory responses were triggered by the H. pylori type IV secretion system (T4SS) and the T4SS-associated adhesin CagL, but not the translocation substrate CagA. Moreover, in contrast to integrin α5β1 playing an essential role in IL-8 induction by H. pylori upon infection of gastric epithelial cells, both integrin α5β1 and integrin αvβ3 were dispensable for IL-8 induction in H. pylori-infected endothelial cells. However, epidermal growth factor receptor (EGFR) is crucial for mediating the potent H. pylori-induced IL-8 response in endothelial cells. This study reveals a novel mechanism by which the H. pylori T4SS and its adhesin subunit, CagL, may contribute to H. pylori pathogenesis by stimulating the endothelial innate immune responses, while highlighting EGFR as a potential therapeutic target for controlling H. pylori-induced inflammation.

The prenylflavonoid Icaritin enhances osteoblast proliferation and function by signal transducer and activator of transcription factor 3 (STAT-3) regulation of C-X-C chemokine receptor type 4 (CXCR4) expression

In this study, we examined the effects of a natural prenylflavonoid Icaritin (ICT), on human osteoblast proliferation and osteogenic function. We observed that ICT dose-dependently enhanced osteoblast proliferation by ~15% over a 7day period. This increase in cell proliferation was associated with corresponding increases in osteoblast functions as measured by ALP secretion, intracellular calcium ions influx and calcium deposition. These anabolic effects were associated with a 4-fold increase in CXCR4 mRNA and protein expression. Silencing of CXCR4 protein expression using small interfering RNA reversed ICT-induced increase in cell proliferation, ALP activity and calcium deposition. Interestingly, we observed that ICT dose-dependently increased STAT-3 phosphorylation; and this resulted in increased binding of phosphorylated STAT-3 to the promoter region of the CXCR4 gene, to increase CXCR4 protein expression. Furthermore, we found that inhibition of STAT-3 phosphorylation resulted in a decrease in CXCR4 protein expression; whilst increasing phosphorylation of STAT-3 using a constitutive active STAT-3 vector significantly increased CXCR4 levels. Moreover, the chemical inhibition of STAT-3 phosphorylation annulled our previously observed ICT-induced increases of osteoblast proliferation and function. Finally, in a rat model of estrogen-deficient osteoporosis, ICT restored both osteoblasts numbers and CXCR4 expression. Taken together, both cellular and animal models support the novel findings that ICT; through the phosphorylation of STAT-3, up-regulated CXCR4, to increase osteoblast proliferation and function.

Extra-corporeal membrane oxygenation in the management of 2009 influenza A (H1N1) refractory respiratory failure

Rapidly progressive acute respiratory failure attributed to 2009 H1N1 influenza A infection has been reported worldwide-3. Refractory hypoxaemia despite conventional mechanical ventilation and lung protective strategies has resulted in the use a combination of rescue therapies, such as conservative fluid management, prone positioning, inhaled nitric oxide, high frequency oscillatory ventilation and extracorporeal membrane oxygenation (ECMO)4. ECMO allows for pulmonary or cardiopulmonary support as an adjunct to respiratory and cardiac failure, minimising ventilator-associated lung injury (VALI). This permits treatment of the underlying disease process, while concurrently allowing for recovery of the acute lung injury. This case documents a previously healthy twenty-two year old Asian male patient with confirmed pandemic (H 1N1) 2009 influenza A who was successfully managed with ECMO in the setting of severe refractory hypoxaemia and progressive hypercapnia.

Inhibition of mast cell PGD2 release protects against mannitol-induced airway narrowing

Mannitol inhalation increases urinary excretion of 9alpha,11beta-prostaglandin F2 (a metabolite of prostaglandin D2 and marker of mast cell activation) and leukotriene E4. The present study tested the hypothesis that beta2-adrenoreceptor agonists and disodium cromoglycate (SCG) protect against mannitol-induced bronchoconstriction by inhibition of mast cell mediator release. Fourteen asthmatic subjects inhaled mannitol (mean dose 252+/-213 mg) in order to induce a fall in forced expiratory volume in one second (FEV1) of > or = 25%. The same dose was given 15 min after inhalation of formoterol fumarate (24 microg), SCG (40 mg) or placebo. Pre- and post-challenge urine samples were analysed by enzyme immunoassay for 9alpha,11beta-prostaglandin F2 and leukotriene E4. The maximum fall in FEV1 of 32+/-10% on placebo was reduced by 95% following formoterol and 63% following SCG. Following placebo, there was an increase in median urinary 9alpha,11beta-prostaglandin F2 concentration from 61 to 92 ng.mmol creatinine(-1), but no significant increase in 9alpha,11beta-prostaglandin F2 concentration in the presence of either formoterol (69 versus 67 ng.mmol creatinine(-1)) or SCG (66 versus 60 ng.mmol creatinine(-1)). The increase in urinary leukotriene E4 following placebo (from 19 to 31 ng.mmol creatinine(-1)) was unaffected by the drugs. These results support the hypothesis that the drug effect on airway response to mannitol is due to inhibition of mast cell prostaglandin D2 release.

Evidence of mast cell activation and leukotriene release after mannitol inhalation

The aim of this study was to investigate if mannitol inhalation, as a model of exercise-induced bronchoconstriction (EIB), causes mast cell activation and release of mediators of bronchoconstriction. Urinary excretion of previously identified mediators of EIB was investigated in association with mannitol-induced bronchoconstriction. Twelve asthmatic and nine nonasthmatic subjects inhaled mannitol and urine was collected 60 min before and for 90 min after challenge. The urinary concentrations of leukotriene (LT)E4, the prostaglandin (PG)D2 metabolite and the mast cell marker 9alpha,11beta-PGF2 were measured by enzyme immunoassay. N(tau)-methylhistamine was measured by radioimmunoassay. In asthmatic subjects, inhalation of a mean+/-SEM dose of 272+/-56 mg mannitol induced a reduction in forced expiratory volume in one second (FEV1) of 34.5+/-2.1%. This was associated with increases in urinary 9alpha,11beta-PGF2 (91.9+/-8.2 versus 66.9+/-6.6 ng x mmol creatinine(-1), peak versus baseline) and LTE4 (51.3+/-7.5 versus 32.9+/-4.7). In nonasthmatic subjects, the reduction in FEV1 was 1.0+/-0.5% after inhaling 635 mg of mannitol. Although smaller than in the asthmatics, significant increases of urinary 9alpha,11beta-PGF2 (68.4+/-6.9 versus 56.0+/-5.8 ng x mmol creatinine(-1)) and LTE4 (58.5+/-5.3 versus 43.0+/-3.3 ng x mmol creatinine(-1)) were observed in the nonasthmatic subjects. There was also a small increase in urinary excretion of N(tau)-methylhistamine in the nonasthmatics, but not in the asthmatics. The increased urinary levels of 9alpha,11beta-prostaglandin F2 support mast cell activation with release of mediators following inhalation of mannitol. Increased bronchial responsiveness to the released mediators could explain the exclusive bronchoconstriction in asthmatic subjects.

Aerosolized drugs: current regulatory perspective

By understanding the way the regulatory concepts of safety and effectiveness are interpreted by CDER, especially by the Division of Pulmonary Drug Products, value can be added to the data developed. Keeping regulatory requirements in mind during early product development aids rapid evaluation of aerosol drug candidates and can lead to more efficient decisions about further development. Health care practitioners, the medical research community, and patient advocates can and do have a voice in the development of new regulations.

Responsiveness to mannitol in asthmatic subjects with exercise- and hyperventilation-induced asthma

We investigated airway responsiveness to mannitol, a new hyperosmolar challenge, in persons hyperresponsive to airway drying. We studied 36 asthmatic subjects, 18 to 40 yr of age, responsive to exercise (n = 23) and eucapnic hyperventilation (n = 28) defined by a 10% fall in FEV1. Fifteen subjects performed both challenges. All subjects performed a challenge with dry powder mannitol, encapsulated and delivered via a Dinkihaler until a 15% decrease in FEV1 was documented or a cumulative dose of 635 mg was delivered. All subjects responsive to eucapnic hyperventilation and all but one subject responsive to exercise were responsive to mannitol. Sixty-nine percent of subjects had a positive response to mannitol after less than 155 mg (6 capsules) and 94% less than 320 mg (10 capsules). The provoking dose of mannitol required to cause a 15% fall in FEV1 (PD15) was related to the severity of the response to exercise (Pearson's correlation coefficient [rp] = 0.68, p < 0.01) and eucapnic hyperventilation (rp = 0.68, p < 0.01) in subjects who were not taking inhaled corticosteroids. The mean (+/- SD) maximum percent fall in FEV1 after mannitol was 24.4 +/- 6.2% and recovery to bronchodilator occurred within 10 min in most subjects. The mannitol test is simple, inexpensive, faster to perform than hyperpnea with dry air and could become an office-based test. Further studies are now required to determine the sensitivity of mannitol to identify exercise-induced asthma in a random population.