Use of multiple pharmacodynamic measures to deconstruct the Nix-TB regimen in a short-course murine model of tuberculosis

A major challenge for tuberculosis (TB) drug development is to prioritize promising combination regimens from a large and growing number of possibilities. This includes demonstrating individual drug contributions to the activity of higher-order combinations. A BALB/c mouse TB infection model was used to evaluate the contributions of each drug and pairwise combination in the clinically relevant Nix-TB regimen [bedaquiline-pretomanid-linezolid (BPaL)] during the first 3 weeks of treatment at human equivalent doses. The rRNA synthesis (RS) ratio, an exploratory pharmacodynamic (PD) marker of ongoing Mycobacterium tuberculosis rRNA synthesis, together with solid culture CFU counts and liquid culture time to positivity (TTP) were used as PD markers of treatment response in lung tissue; and their time-course profiles were mathematically modeled using rate equations with pharmacologically interpretable parameters. Antimicrobial interactions were quantified using Bliss independence and Isserlis formulas. Subadditive (or antagonistic) and additive effects on bacillary load, assessed by CFU and TTP, were found for bedaquiline-pretomanid and linezolid-containing pairs, respectively. In contrast, subadditive and additive effects on rRNA synthesis were found for pretomanid-linezolid and bedaquiline-containing pairs, respectively. Additionally, accurate predictions of the response to BPaL for all three PD markers were made using only the single-drug and pairwise effects together with an assumption of negligible three-way drug interactions. The results represent an experimental and PD modeling approach aimed at reducing combinatorial complexity and improving the cost-effectiveness of in vivo systems for preclinical TB regimen development.

Effect of woodchip bedding during wet conditions on feedlot cattle productivity, behaviour and relative adrenal gland weight

Problems associated with muddy pens have been identified as some of the most serious animal welfare issues related to outdoor feedlot beef production, but there is relatively little work examining the use of woodchip bedding for lot-fed beef cattle under conditions of cold, wet, but non-freezing winters on soil under-bases. This study examined the effects of graded levels of woodchip on the performance and behaviour of feedlot cattle housed in wet pen conditions. Bos taurus steers (n = 300; 379.1 ± 24.1 kg) were blocked by weight and breed and randomly assigned to 30 10-steer feedlot pens provided with either no woodchip bedding (Control, n = 10) manure interface only, or 15 cm depth of woodchip bedding (W15, n = 10) or 30 cm depth of woodchip bedding (W30, n = 10). The steers were housed in these treatment pens for 109 days on a feedlot ration, and the pens were irrigated so that approximately 74 mm of total precipitation (irrigation + natural rainfall) fell onto the pen surface every 30 days. Temperatures were mostly <20 °C maximum and -1 to 5 °C minimum. Steers were weighed on five occasions. Animal position and posture in pen were recorded once a week over an 8-hour day-time period. Carcase characteristics were measured, and adrenal gland weights were recorded. Providing woodchip bedding increased liveweight gain (P < 0.001) and gain:feed (G:F, P = 0.012) after day 28, increased DM intake (DMI) after day 92 (P = 0.049), and increased carcase weight (P = 0.001) and dressing percentage (P = 0.023). There was no additional benefit of W30 over W15 for liveweight gain or DMI, but the benefit of W15 for G:F was lower than that of W30 by the end of the feeding period (P = 0.012). There were no effects of bedding on other carcase quality traits. Steers in Control pens utilised the front of the pen for lying and standing more than the W15 and W30 steers (P < 0.001) suggesting the steers in the Control pens perceived the front of the pen as less aversive, potentially due to increased drainage compared to rest of the pen and proximity to feed bunk. Adrenal gland weight/kg and carcase weight tended to be higher in the Control treatment group than the W30 steers (P = 0.077). This research has demonstrated that for a 109-day feeding period in cold, wet conditions, steer performance and welfare can be improved by providing a minimum of 15 cm woodchip bedding.

Use of Multiple Pharmacodynamic Measures to Deconstruct the Nix-TB Regimen in a Short-Course Murine Model of Tuberculosis

A major challenge for tuberculosis (TB) drug development is to prioritize promising combination regimens from a large and growing number of possibilities. This includes demonstrating individual drug contributions to the activity of higher-order combinations. A BALB/c mouse TB infection model was used to evaluate the contributions of each drug and pairwise combination in the clinically relevant Nix-TB regimen (bedaquiline-pretomanid-linezolid [BPaL]) during the first three weeks of treatment at human equivalent doses. RS ratio, an exploratory pharmacodynamic (PD) marker of ongoing Mycobacterium tuberculosis rRNA synthesis, to-gether with solid culture CFU and liquid culture time to positivity (TTP) were used as PD markers of treatment response in lung tissue; and their time course profiles were mathematically modeled using rate equations with pharmacologically interpretable parameters. Antimicrobial interactions were quantified using Bliss independence and Isserlis formulas. Subadditive (or antagonistic) and additive effects on bacillary load, assessed by CFU and TTP, were found for bedaquiline-pretomanid and linezolid-containing pairs, respectively. In contrast, subadditive and additive effects on rRNA synthesis were found for pretomanid-linezolid and bedaquiline-containing pairs, respectively. Additionally, accurate predictions of the response to BPaL for all three PD markers were made using only the single-drug and pairwise effects together with an assumption of negligible three-way drug interactions. The results represent an experimental and PD modeling approach aimed at reducing combinatorial complexity and improving the cost-effectiveness of in vivo systems for preclinical TB regimen development.

Type 1 diabetes in North East England and North Cumbria: patterns and time trends in 0-14-year-olds from 2012 to 2020

Introduction

It is important to understand patterns in the epidemiology of type 1 diabetes because they may provide insight into its etiology. We examined the incidence of type 1 diabetes in children aged 0-14 years, and patient demographics and clinical parameters at presentation, over the period 2012-2020 using the North East and North Cumbria Young Persons diabetes register.

Methods

Patients up to the age of 14 years with type 1 diabetes, and their families- managed in a total of 18 young persons diabetes clinics-were approached in person at the time of clinic appointments or in the days following diagnosis and they consented to their data being included in the register. Data were submitted regionally to a central unit. Descriptive statistics including crude and age-specific incidence rates were calculated. Temporal trends were analyzed using Joinpoint regression. Comparisons in incidence rates were made between age, sex and areas of higher and lower affluence as measured by the Index of Multiple Deprivation (IMD).

Results

A total of 943 cases were recorded between January 2012 and December 2020. Median age at diagnosis was 8.8 years (Q1: 5.3, Q3: 11.7). There were more males than females (54% male). The median HbA1c at diagnosis was 100 mmoL/L (IQR: 39) and over one third (35%) were in ketoacidosis (pH < 7.3). Crude incidence decreased from 25.5 (95% confidence interval [CI] 20.9, 29.9) in 2012 to 16.6 (95% CI: 13.0, 20.2) per 100,000 in 2020 (5.1% per annum, 95% CI 1.1, 8.8%). During the period of the study there was no evidence of any trends in median age, HbA1c, BMI or birthweight (p = 0.18, 0.80, 0.69, 0.32) at diagnosis. Higher rates were observed in males aged 10-14 years, but similar rates were found for both sexes aged 0-9 years and there was no difference between areas of higher or lower deprivation (p = 0.22).

Conclusion

The incidence of diabetes in the young may be falling in the North East of England and North Cumbria. The reasons are unclear as there were no associations identified between levels of deprivation or anthropometric measurements. Potential mechanisms include alterations in socioeconomic background or growth pattern. Further research is needed to understand the reasons behind this finding.

A248 OUTCOMES OF COVID-19 ILLNESS AND ACCESS TO APPROPRIATE TREATMENT IN LIVER TRANSPLANT RECIPIENTS IN BRITISH COLUMBIA THROUGHOUT THE PANDEMIC

Background

COVID-19 continues to cause significant illness and mortality worldwide. Solid Organ Transplant Recipients (SOTR) have a higher rate of COVID-19 infection and worse outcomes than those who are immunocompetent. Dexamethasone, tocilizumab, and baricitinib have improved inpatient outcomes. Sotrovimab, remdesivir, and nirmatrelvir/ritonavir have recently been approved for used in high risk, minimally symptomatic outpatients. Previous experience has shown that use of monoclonal antibodies and oral antiviral agents have reduced morbidity and mortality of COVID-19 in SOTR.

Purpose

To assess the experiences and outcomes of COVID-19 and access to directed therapy in SOTR in British Columbia (BC).

Method

Data was compiled from patient disclosure to liver transplant clinicians on COVID-19 infection and gathered from patient charts in the SOTR Clinic at Vancouver General Hospital. Inclusion criteria were patients followed at the clinic with a positive COVID-19 test or clinical confirmation of COVID-19 syndrome. This is a retrospective, quality assurance study and did not require ethics review.

Result(s)

158 SOTR reported COVID-19 infections between March 2020 and September 2022. 3 patients died within 30 days of COVID-19 infection, 2 (1.26%) of which the cause of death was directly due to COVID-19, and the other who had cholangitis with severe sepsis and multi-organ system failure. 24 patients required admission to hospital, 7 requiring critical care support.

41 patients did not receive any therapy for COVID-19: there was none available at that time (n=26), it was contraindicated due to a drug interaction (n=2) or medical condition (n=1), was refused (n=1), or the infection was reported too late to qualify (n=10). 83% (92/112) of outpatients received available anti-viral treatment: sotrovimab (n=27), remdesivir (n=63), or nirmatrelvir/ritonavir (n=2). In inpatients (n=24), 13 received corticosteroids, 6 dual treated with tocilizumab (n=4) or baracitinib (n=2). 4 inpatients received remdesivir.

Three patients were treated in hospital after initiating outpatient therapy, one with progression of COVID-19 illness despite starting remdesivir. Two patients had adverse effects of medications provided: one was prescribed nirmatrelvir/ritonavir by a physician outside of the transplant program, which caused tacrolimus toxicity (serum concentration of 69.4 ng/mL) with nausea, vomiting, and diarrhea. Another patient had an episode of hypotension after receiving sotrovimab and sustained an acute kidney injury (AKI). Both patients fully recovered. There were no deaths on antiviral therapy.

Of 145 patients who had laboratory investigations done within 30 days of COVID-19 infection, 16 had a transient rise in liver enzymes, 14 had an AKI and 11required an adjustment in their tacrolimus dose.

Conclusion(s)

Involving the liver transplant team early in the course of COVID-19 illness allows patients to safely access COVID-19 directed therapy to avoid progression of illness, and medication interactions or toxicity.

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Disclosure of Interest

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The impact and experience of cardiac cachexia in advanced heart failure patients and their caregivers

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Northern Ireland Chest Heart & Stroke

Background

Cardiac cachexia is a multifactorial wasting syndrome, which is characterised by unintentional weight loss, a reduction in skeletal muscle mass, and reduced quality of life. There is a paucity of qualitative research outlining the impact and experience of cardiac cachexia in advanced heart failure patients and their caregivers. Research in this area may promote a better understanding of the syndrome, enhance current treatment strategies, and highlight priorities for patient care.

Purpose

To qualitatively investigate the impact and experience of cardiac cachexia in advanced heart failure patients and their caregivers.

Methods

Semi-structured interviews were performed with advanced heart failure (NYHA functional class III-IV) patients meeting diagnostic criteria for cardiac cachexia (number (n) = 8) and their caregivers (n = 5). Interview questions followed a "laddered style approach", with a focus on determining the experience of cachexia for patients and carers, and its impact on their daily lives. Interviews were digitally recorded and transcribed verbatim. Average interview duration was 43 (15-64) minutes. Data were thematically analysed, using the 6-step approach of Braun & Clarke. Themes were developed and refined by several members of the research team to ensure rigor.

Results

Four key themes were developed from the data. 1) "Changed relationship with food and eating": patients with cachexia referred to eating as something they now ‘make’ themselves do without enjoyment, often just to placate their caregiver. Caregivers noted this change in habit and were concerned about inadequate nutritional intake due to the patient’s lack of interest in food. 2) "Not me in the mirror": patients struggled with their appearance and had a negative perception of themselves, linked to their weight loss. Caregivers were similarly aware of the physical changes in their loved ones and emotionally impacted. 3) "Lack of understanding regarding cachexia": despite the patient and caregivers’ concerns, they had a perception that healthcare professionals were just ‘fobbing you off’. Even though weight loss was noted and distressing to patients and caregivers, there was little clinical recognition of it, nor any advice or support from the clinical team regarding management. 4) "Uncertainty regarding the future": patients and caregivers recognised cachexia as a bad sign, and many expressed concerns about their future health and prognosis.

Conclusion

These novel qualitative findings highlight the severe impact of cardiac cachexia on the daily lives of patients and caregivers, and demonstrate their limited understanding of the syndrome. To improve care, professionals need to recognise and discuss cachexia with heart failure patients and caregivers, supporting them to cope with prognostic implications and develop more effective management strategies.

Optimizing first line treatments for adults with OCD

OCD is characterized by obsessions (recurrent, intrusive, unwanted thoughts, images or impulses and compulsions (repetitive behaviors or mental acts that the individual feels compelled to perform), which can manifest together or separately (Fineberg et al., 2020). NICE guidelines suggest that low intensity psychological treatments (including ERP) is the first line treatment for OCD, and that a "stepped care" treatment approach for OCD reserves combination treatment for adults with OCD with severe functional impairment, and for adults without an adequate response to: 1) treatment with an SSRI alone (12 weeks duration) or 2) CBT (including ERP) alone (NICE, 2005). Existing US treatment guidelines (APA guidelines) suggest that there are three first-line treatments for OCD (SSRI, CBT, SSRI+CBT) and recommends combined treatment for patients with an unsatisfactory response to monotherapy or for patients with severe OCD. Although, systematic review and meta-analysis of studies published in 1993-2014 suggest that combination treatment was not significantly better than CBT plus placebo (Ost et al., 2015), based on data from a recent systematic and meta-analysis which searched the two controlled trials registers maintained by the Cochrane Collaboration Common Mental Disorders group, the combination treatment approach is likely to be more effective than psychotherapeutic interventions alone, at least in severe obsessive-compulsive disorder (Skapinakis et al., 2016a). Based on data from Optimal treatment for OCD study conducted by Fineberg et al., (2018) combined treatment appeared to be the most effective especially when compared to CBT monotherapy, but SSRI monotherapy was found as the most cost effective. In this review we summarize available treatment recommendations.

Magseed localisation of non-palpable breast lesions: experience from a single centre

AIM

To prospectively analyse patients undergoing magnetic seed (Magseed) localisation (MSL) to evaluate the outcome, and to retrospectively compare re-excision rates for MSL with previous wire-guided localisation (WGL) to assess the hypothesis that the introduction of MSL may lead to a lower re-excision rate.

MATERIALS AND METHODS

MSL commenced at University Hospital Crosshouse in December 2017. No other changes were made to radiological or surgical practice during this time. Data were collected prospectively on all patients undergoing MSL between December 2017 and December 2019, in a single breast unit. Data were gathered retrospectively on patients who had undergone localised breast procedures between January 2016 and December 2019 for comparison of re-excision rates.

RESULTS

Two hundred and fifty-five patients underwent MSL surgery between December 2017 and December 2019. Of those, 98% (n=250) patients underwent successful MSL at the first attempt. The Magseed was identified intraoperatively in 100% patients and surgical excision was performed. The re-excision rate reduced from 18.9% in 2016/2017, to 11.6% in 2018/2019 (p=0.098).

CONCLUSION

In conclusion, Magseed localisation has proved to be a safe and effective way of localising breast lesions, with the advantage of high accuracy. The reduction in re-excision rates at University Hospital Crosshouse with the introduction of Magseed® localisation is a potential benefit, which requires further study.

A149 REAL WORLD OUTCOMES OF NON-MEDICAL SWITCHING OF INFLIXIMAB BIOSIMILAR IN BRITISH COLUMBIA FOR THE TREATMENT OF INFLAMMATORY BOWEL DISEASE (IBD)

Background

A mandated non-medical switch to the infliximab biosimilars was launched in British Columbia in 2019. British Columbia was the first province in Canada to mandate the switch from the originator infliximab (RemicadeTM) to one of the 2 approved biosimilars (InflectraTM or RenflexisTM). There is limited data for mandatory non-medical switching in IBD as was undertaken in BC.

Aims

This study aimed to obtain real-world evidence evaluating the clinical outcomes of nonmedical switch from Remicade to the infliximab biosimilars.

Methods

This is a retrospective observational study from the IBD Centre of BC (a tertiary care referral centre in Vancouver, BC). Patients on infliximab at the time of the mandated switch were identified through search of the electronic medical record. The primary outcome was drug continuation at 12 months post switch. Secondary outcomes included flare of disease, adverse events, and number of doctor visits within the first 12 months post switch. A comparison group included patients maintained on originator infliximab.

Results

A total of 235 patients were evaluated; 175 patients in the biosimilar switch group, and 60 patients in the control group. Baseline characteristics of the groups were similar. Discontinuation of infliximab occurred in 22 patients (17 in biosimilar switch group and 5 in the control group. There was no difference in the rate of discontinuation of infliximab between the biosimilar group (9.7%) and the originator molecule group (8.3%); chi squared (1, N=235) = 0.1004, p = .75. The most common reason for discontinuation was flare of disease in 6 patients in the biosimilar group and 4 patients in the control group. An additional 4 patients in the biosimilar group and 3 patients in the control group had a flare of symptoms but were maintained on therapy with an escalation of dosage or course of corticosteroids. Two patients had active disease at the time of switch and discontinued therapy. Adverse events accounted for discontinuation in 5 patients on biosimilar and 1 in the control group. These included joint pain, epigastric symptoms, drug intolerance, drug induced lupus, and drug induced pulmonary nodules in the biosimilar group, and drug induced vasculitis in the control group. Two patients in the biosimilar group discontinued due to antibody formation. Two patients in the biosimilar group discontinued therapy due to preference.

Conclusions

In this small subset of the BC IBD population undergoing a non-medical biosimilar switch of infliximab, there was no difference in the discontinuation rate between the biosimilars or the originator infliximab molecule. These findings are consistent with the existing real-world evidence.

Funding Agencies

None

Can Multi-threaded Flux Tubes in Coronal Arcades Support a Magnetohydrodynamic Avalanche?

Magnetohydrodynamic (MHD) instabilities allow energy to be released from stressed magnetic fields, commonly modelled in cylindrical flux tubes linking parallel planes, but, more recently, also in curved arcades containing flux tubes with both footpoints in the same photospheric plane. Uncurved cylindrical flux tubes containing multiple individual threads have been shown to be capable of sustaining an MHD avalanche, whereby a single unstable thread can destabilise many. We examine the properties of multi-threaded coronal loops, wherein each thread is created by photospheric driving in a realistic, curved coronal arcade structure (with both footpoints of each thread in the same plane). We use three-dimensional MHD simulations to study the evolution of single- and multi-threaded coronal loops, which become unstable and reconnect, while varying the driving velocity of individual threads. Experiments containing a single thread destabilise in a manner indicative of an ideal MHD instability and consistent with previous examples in the literature. The introduction of additional threads modifies this picture, with aspects of the model geometry and relative driving speeds of individual threads affecting the ability of any thread to destabilise others. In both single- and multi-threaded cases, continuous driving of the remnants of disrupted threads produces secondary, aperiodic bursts of energetic release.

Prevalence and effect of cardiac cachexia in advanced heart failure patients living in northern ireland

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): Northern Ireland Chest Heart and Stroke

Background/Introduction: Cardiac cachexia (CC) is a multifactorial wasting syndrome, resulting in significant weight loss and reduction in muscle mass. This is reflected in a detrimental effect on the patients’ physical condition, quality of life and increases the patient’s risk of premature death. Nonetheless, cardiac cachexia remains frequently unrecognised in clinical practice and therefore understudied.

Purpose

To determine the prevalence and effect of cardiac cachexia in 200 patients with advanced heart failure (NYHA class III-IV) living in Northern Ireland.

Methods

A mixed methods cross sectional study of patients recruited from a regional heart failure centre. A total of 200 patients with NYHA class III-IV heart failure were consented, enrolled and detailed data collected from their records. Anthropometric measures were taken (i.e. measures of lean muscle mass and fat tissue) and each individual completed three validated questionnaires - EQ-5D-5L (quality of life), FACIT-Fatigue and FAACT (various wellbeing subscales).

Results

This population was predominately male (65.5%), with an average age of 74.4 years. Of the 200 NYHA class III-IV patients recruited, 30 were identified as cachectic (15%) Physically, cachectic patients were approximately 25 kg lighter than non-cachectic patients (p &lt; 0.01) with an average BMI of 21.8 ± 4.4. The cachectic group showed significant reductions in mid-upper arm circumference (p &lt; 0.01), skinfold thickness (p &lt; 0.01) and upper arm fat area (p &lt; 0.01), in comparison to the non-cachectic group. Measures of muscle mass were reduced, for example upper arm muscle circumference and area (p &lt; 0.01), as well as grip strength (p &lt; 0.01 for both right and left hands). Quality of life results from the EQ-5D-5L [see figure part b)] indicated an overall reduction for the cachectic group (p = 0.047). Of the EQ-5D-5L subscales, mobility and ‘usual activities’ were significantly reduced (p = 0.02 and p &lt; 0.01 respectively), highlighting a significant change in the daily routine and ability of these patients. The FACIT-Fatigue questionnaire showed cachectic patients to be significantly more fatigued (p &lt; 0.01) [see figure part a)], whilst the FAACT demonstrated reduced physical wellbeing (p = 0.02) and greater issues with diet and appetite (p &lt; 0.01).

Conclusions

This is the first prevalence study of cardiac cachexia within Northern Ireland. The 15% prevalence rate shows that the syndrome is relatively common in the advanced heart failure population. Cardiac Cachexia has severe physical consequences, attributed to an individual’s weight loss in both fat and muscle tissue. Such changes may explain the subsequent decrease in mobility and the ability of these patients to conduct their ‘usual activities’. Increased fatigue, reduced physical wellbeing and issues with diet and appetite only intensify these dire physical effects. It is hoped that these results will highlight the impact of this syndrome and promote targeted interventions.

16 Pharmacological Interventions for Sialorrhoea in Parkinson’s Disease: A Systematic Review

Introduction

We looked at patients with Idiopathic Parkinson’s disease and reviewed articles that used any pharmacological therapy to attempt to reduce the volume or burden of sialorrhoea. The control was patients on placebo or receiving usual best care. The primary outcome was symptom burden of sialorrhoea.

Method

The review was registered on Prospero (CRD42016042470.) 7 electronic databases (MEDLINE, EMBASE, CINAHL, PsycINFO, Cochrane Central Register of Controlled Trials (CENTRAL), LILACS) were searched until April 2019 using search terms for sialorrhoea and Parkinson’s disease. We additional searched through the last 6 years of abstracts from the International Movement Disorder Conference, Movement Disorder Society International Congress and World Parkinson’s Congress. Hand searching was performed of published journals from the Movement Disorder Journal of the Movement Disorder Society and Neurology. Inclusion criteria included patients aged over 18; patients with a diagnosis of Idiopathic Parkinson’s disease; patients with the complication of sialorrhoea and any pharmacological therapy aimed at reducing sialorrhoea. All articles were assessed for risk of bias independently by two assessors using the Cochrane risk of bias tool.

Results

7 articles were included from the 1,015 screened citations. 3 studies used Botox B as an intervention with clear objective measures and low risk of bias. These studies did show a significant reduction in sialorrhoea however the largest study showed some reporting bias and the others had small numbers and a short follow up period. 1 study looked at Botox A which showed significant improvement in sialorrhoea but had short follow-up.

Conclusion

Most studies have very small numbers and were followed up for only 1 month. There was significant heterogeneity in outcome measures but little evidence of significant harm from from the treatments studied. Overall, more robust evidence is required in order to achieve a gold standard in the treatment of sialorrhoea.

A prospective cohort study of the safety of breast cancer surgery during COVID-19 pandemic in the West of Scotland

INTRODUCTION

In order to minimise the risk of breast cancer patients for COVID-19 infection related morbidity and mortality prioritisation of care has utmost importance since the onset of the pandemic. However, COVID-19 related risk in patients undergoing breast cancer surgery has not been studied yet. We evaluated the safety of breast cancer surgery during COVID-19 pandemic in the West of Scotland region.

METHODS

A prospective cohort study of patients having breast cancer surgery was carried out in a geographical region during the first eight weeks of the hospital lockdown and outcomes were compared to the regional cancer registry data of pre-COVID-19 patients of the same units (n = 1415).

RESULTS

188 operations were carried out in 179 patients. Tumour size was significantly larger in patients undergoing surgery during hospital lockdown than before (cT3-4: 16.8% vs. 7.4%; p < 0.001; pT2 - pT4: 45.5% vs. 35.6%; p = 0.002). ER negative and HER-2 positive rate was significantly higher during lockdown (ER negative: 41.3% vs. 17%, p < 0.001; HER-2 positive: 23.4% vs. 14.8%; p = 0.004). While breast conservation rate was lower during lockdown (58.6% vs. 65%; p < 0.001), level II oncoplastic conservation was significantly higher in order to reduce mastectomy rate (22.8% vs. 5.6%; p < 0.001). No immediate reconstruction was offered during lockdown. 51.2% had co-morbidity, and 7.8% developed postoperative complications in lockdown. There was no peri-operative COVID-19 infection related morbidity or mortality.

CONCLUSION

breast cancer can be safely provided during COVID-19 pandemic in selected patients.

Endothelin receptor antagonist improves donor lung function in an ex vivo perfusion system

BACKGROUND

A lung transplant is the last resort treatment for many patients with advanced lung disease. The majority of donated lungs come from donors following brain death (BD). The endothelin axis is upregulated in the blood and lung of the donor after BD resulting in systemic inflammation, lung damage and poor lung graft outcomes in the recipient. Tezosentan (endothelin receptor blocker) improves the pulmonary haemodynamic profile; however, it induces adverse effects on other organs at high doses. Application of ex vivo lung perfusion (EVLP) allows the development of organ-specific hormone resuscitation, to maximise and optimise the donor pool. Therefore, we investigate whether the combination of EVLP and tezosentan administration could improve the quality of donor lungs in a clinically relevant 6-h ovine model of brain stem death (BSD).

METHODS

After 6 h of BSD, lungs obtained from 12 sheep were divided into two groups, control and tezosentan-treated group, and cannulated for EVLP. The lungs were monitored for 6 h and lung perfusate and tissue samples were processed and analysed. Blood gas variables were measured in perfusate samples as well as total proteins and pro-inflammatory biomarkers, IL-6 and IL-8. Lung tissues were collected at the end of EVLP experiments for histology analysis and wet-dry weight ratio (a measure of oedema).

RESULTS

Our results showed a significant improvement in gas exchange [elevated partial pressure of oxygen (P = 0.02) and reduced partial pressure of carbon dioxide (P = 0.03)] in tezosentan-treated lungs compared to controls. However, the lungs hematoxylin-eosin staining histology results showed minimum lung injuries and there was no difference between both control and tezosentan-treated lungs. Similarly, IL-6 and IL-8 levels in lung perfusate showed no difference between control and tezosentan-treated lungs throughout the EVLP. Histological and tissue analysis showed a non-significant reduction in wet/dry weight ratio in tezosentan-treated lung tissues (P = 0.09) when compared to control.

CONCLUSIONS

These data indicate that administration of tezosentan could improve pulmonary gas exchange during EVLP.

Understanding the holistic experiences of living with a kidney transplant: an interpretative phenomenological study (protocol)

Background

Currently very little is known about the perceptions and experiences of kidney transplant recipients from a qualitative perspective. As highlighted by the European Kidney Health Alliance recommendations, providing holistic care to kidney patients is important however this is currently an unmet care need in renal disease. It is imperative to understand patient experiences to ensure that they are included in key strategies and future renal service planning. Ignoring these important patient views means that there is a significant risk of inappropriate renal service provision and lack of adequate support impacting on overall health.

Method

A purposive sampling strategy will recruit individuals currently living with a kidney transplant, 6 months to 5 years post-transplant. A maximum of 30 patients will be recruited between two Regional Nephrology units within the United Kingdom via clinical gatekeepers. In-depth interviews will be undertaken with participants living with a kidney transplant across the two sites. Interviews will be digitally-recorded, transcribed verbatim and subjected to interpretative phenomenological analysis.

Discussion

Renal healthcare professionals need to understand more than the biological impact of receiving a kidney transplant. Understanding the holistic and multi-domain experiences that these patients experience will help healthcare professionals to recognize the needs of this group and ensure more responsive care.