Divergent molecular networks program functionally distinct CD8+ skin-resident memory T cells

Skin-resident CD8+ T cells include distinct interferon-γ-producing [tissue-resident memory T type 1 (TRM1)] and interleukin-17 (IL-17)-producing (TRM17) subsets that differentially contribute to immune responses. However, whether these populations use common mechanisms to establish tissue residence is unknown. In this work, we show that TRM1 and TRM17 cells navigate divergent trajectories to acquire tissue residency in the skin. TRM1 cells depend on a T-bet-Hobit-IL-15 axis, whereas TRM17 cells develop independently of these factors. Instead, c-Maf commands a tissue-resident program in TRM17 cells parallel to that induced by Hobit in TRM1 cells, with an ICOS-c-Maf-IL-7 axis pivotal to TRM17 cell commitment. Accordingly, by targeting this pathway, skin TRM17 cells can be ablated without compromising their TRM1 counterparts. Thus, skin-resident T cells rely on distinct molecular circuitries, which can be exploited to strategically modulate local immunity.

Graded Quasiperiodic Metamaterials Perform Fractal Rainbow Trapping

The rainbow trapping phenomenon of graded metamaterials can be combined with the fractal spectra of quasiperiodic waveguides to give a metamaterial that performs fractal rainbow trapping. This is achieved through a graded cut-and-project algorithm that yields a geometry for which the effective projection angle is graded along its length. As a result, the fractal structure of local band gaps varies with position, leading to broadband "fractal" rainbow trapping. We demonstrate this principle by designing an acoustic waveguide, which is characterised using theory, simulation and experiments.

Investigating blood alcohol concentrations in injury- related deaths before and during the COVID-19 national lockdown in Western Cape Province, South Africa: A cross-sectional retrospective review

BACKGROUND

Alcohol is a significant contributor to injury-related morbidity and mortality in South Africa (SA). During the COVID-19global pandemic, restrictions to movement and to legal access to alcohol (i.e. ethanol) were introduced in SA.

OBJECTIVES

To investigate the effect of alcohol bans during the COVID-19 lockdown periods on injury-related mortality and blood alcoholconcentrations (BACs) in these deaths.

METHODS

A retrospective, cross-sectional analysis of injury-related deaths in Western Cape Province (WC), SA, between 1 January 2019 and31 December 2020 was conducted. Cases where BAC testing was performed were further examined according to the periods of lockdownand alcohol restrictions.

RESULTS

A total of 16 027 injury-related cases were admitted to Forensic Pathology Service mortuaries in the WC over the 2-year period. Anaverage decrease of 15.7% injury-related deaths in 2020 compared with 2019 was noted, as well as a 47.7% decrease in injury-related deathsduring hard lockdown (April - May 2020) compared with the same period in 2019. In the injury-related deaths, 12 077 (75.4%) had bloodspecimens collected for BAC testing. In 5 078 (42.0%) of submitted cases, a positive BAC (≥0.01 g/100 mL) was reported. No significantdifference was observed in the mean positive BAC between 2019 and 2020. However, in April and May 2020, the mean BAC observed(0.13 g/100 mL) was less than that in 2019 (0.18 g/100 mL). A high number of positive BACs in the 12- 17-year age group (23.4%) was observed.

CONCLUSION

There was a clear decrease in injury-related deaths in the WC during the COVID-19-related lockdown periods, whichcoincided with the alcohol ban and restriction of movement, and an increase following relaxation of restrictions on alcohol sales andmovement. The data illustrate that mean BACs were similar between all periods of alcohol restriction compared with 2019, apart from hardlockdown in April - May 2020. This coincided with a smaller mortuary intake during the level 5 and 4 lockdown periods.

Investigating blood alcohol concentrations in injury-related deaths before and during the COVID-19 National lockdown in Western Cape, South Africa: A cross-sectional retrospective review

BACKGROUND

Alcohol is a significant contributor to injury-related morbidity and mortality in South Africa (SA).  During the COVID-19 global pandemic, restrictions to movement and to the legal access of alcohol* were introduced in SA.  This study aimed to investigate the effect of alcohol bans during the COVID-19 lockdown periods on injury-related mortality and the blood alcohol concentrations (BAC) in these deaths.

METHODS

A retrospective, cross-sectional analysis of injury-related deaths in Western Cape (WC) province, SA, between 1 January 2019 to 31 December 2020 was conducted. Cases where BAC testing was performed were further examined according to the periods of lockdown (AL5-1) and alcohol restrictions.

RESULTS

A total of 16,027 injury-related cases were admitted to Forensic Pathology Service mortuaries in the WC over the two-year period.  An average decrease of 15.7% injury-related deaths in 2020 compared to 2019 was noted, as well as a 47.7% decrease in injury-related deaths during hard lockdown (April -May 2020) compared to the same period in 2019. In the injury-related deaths, 12,077 (75.4%) had blood specimens collected for BAC testing. In 5,078 (42.0%) of submitted cases, a positive BAC (≥0.01g/100 mL) was reported. No significant difference was observed in the mean positive BAC between 2019 and 2020, however in April and May 2020, the mean BACs observed (0.13 g/100 mL) was less than that in 2019 (0.18 g/100 mL). A high number of positive BACs in the 12-17-year age group (±23.4%) was observed.

CONCLUSION

There was a clear decrease in injury-related deaths in the WC during the COVID-19-related lockdown periods that coincided with the alcohol ban and restriction of movement and an increase following relaxation of restrictions on alcohol sales and movement. The data illustrated that mean BACs were similar between all periods of alcohol restriction compared to 2019, apart from hard lockdown in April-May, 2020.  This coincided with a smaller mortuary intake during the level 5 and 4 lockdown periods.   Keywords: Alcohol; blood alcohol concentration; COVID-19; injury; lockdown; South Africa; violent death; Western Cape   * Alcohol refers to ethanol.

Antimicrobial use in animals: a journey towards integrated surveillance

In 2015, the World Organisation for Animal Health (WOAH, founded as OIE) initiated the annual collection of data on antimicrobials intended for use in animals using a Microsoft Excel questionnaire. In 2022, WOAH initiated the migration to a customised interactive online system: ANIMUSE Global Database. This system enables national Veterinary Services not only to monitor and report data more easily and more accurately, but also to visualise, analyse and use data for surveillance purposes to their own benefit in the implementation of national action plans on antimicrobial resistance. This journey started seven years ago, with progressive improvements in the way data are collected, analysed and reported and continuous adaptations to overcome various challenges encountered (e.g. data confidentiality, training of civil servants, calculation of active ingredients, standardisation to enable fair comparisons and trend analyses, and data interoperability). Technical developments have been key in the success of this endeavour. However, it is important not to underestimate the importance of the human element: to listen to WOAH Members and their needs, and to exchange to solve issues, adapt tools, and gain and maintain trust. The journey is not over yet, and more developments are foreseen, such as to complement current data sources with data collected directly at the farm level; strengthen interoperability and integrated analysis with cross-sectoral databases; and facilitate institutionalisation of data collection and systematic use in monitoring, evaluation, lesson learning, reporting and, eventually, surveillance of antimicrobial use and antimicrobial resistance when implementing and updating national action plans. This paper describes how all these challenges were overcome and how future challenges will be addressed.

The Role of Alcohol and Drug Intoxication in Fire-Related Incidents in Africa: A Systematic Review

Fire-related burns contribute significantly to the global burden of burn injury and mortality. Alcohol and/or drug intoxication poses a risk to burn and fire-related injury, whether intentional or unintentional, but such evidence is scarce in the African context. This review aimed to fill the knowledge gap on health determinants of fire-related morbidity and mortality regionally by investigating the role of alcohol and drug intoxication in such events. Using key concepts, an extensive search was performed on 25 databases for relevant publications. Eligible articles were critically appraised using the appraisal tool for cross-sectional studies (AXIS tool), adapted to the review's objectives and outcomes. A total of 42 articles were included, of which less than half were solely investigating burn/fire-related events. Others indirectly mentioned burn injuries as part of larger health burdens such as injury, trauma, violence and other diseases. The measurement of alcohol and/or drug intoxication was inconsistent between studies with varying results. Alcohol and drug impairment in burn incidents in Africa requires evidence-based epidemiological research, and this review illustrated the limited scope of this topic in current literature. Routine toxicological results from post-mortem examinations were identified as important data sources and several research recommendations were provided.

Exploring the contribution of mechano-sensing to cardiomyopathy

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Medical Research Council (MR/V009540/1),

Wellcome Trust (201543/B/16/Z)

British Heart Foundation (FS/12/40/29712).

Hypertrophic cardiomyopathy (HCM) is an inherited cardiac condition associated with diastolic dysfunction and sudden cardiac death. Disease genes for HCM are traditionally coding for proteins involved in force generation. More recently, it has emerged that variants in genes coding for proteins involved in biomechanical stress-signalling can also cause HCM.

One such protein is filamin C, with proposed mechano-sensing functions in the heart. Within the protein, the immunoglobulin-like domain 20 (Ig20) may play a crucial role in mediating binding to muscle specific ligands. While the mechano-sensing functions of filamin C have been investigated well in skeletal muscle, the underlying cardiac disease mechanisms are not completely understood.

Aim

This work attempts to provide insights into the role of filamin C in cardiac mechano-sensing and dissect disease pathways leading to HCM in the presence of the FLNC variants in Ig20.

Methods

Using mass spectrometry, we aimed to provide a detailed analysis of the proteome of mice carrying the filamin C variant, using ventricular tissue samples from 14wk old homozygous mice. Samples were subject to molecular biology technical and underwent subcellular fractionation (n = 6 per genotype) and were investigated by label-free mass spectrometry.

Results

Utilising whole genome sequencing, a heterozygous FLNC missense variant in Ig20 was identified in a three-generation family affected by HCM. Mice carrying this variant recapitulate molecular features of HCM in the homozygous setting. Three proteins (FLNC, MYH7, MYOT) were found to be upregulated in the myofilament-enriched fraction. Up-regulations of key proteins were found to relocalise towards load-baring sites.

Conclusion

Our data indicate that changes in filamin C and its binding partners expression and localisation are involved in the pathogenesis of HCM in this mouse model.

Crucial functions of alpha-actinin 2 in the embryonic heart

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Wellcome Trust; British Heart Foundation

Background/Introduction

Alpha-actinin is an integral protein of the Z-discs in heart and skeletal muscle cells, with important structural and signalling functions.  Missense variants in alpha-actinin can cause inherited conditions, e.g. myopathies and cardiomyopathies. The underlying disease mechanisms are still unknown.

Purpose

In order to study the disease mechanisms of an alpha-actinin missense variant, which is known to cause Hypertrophic Cardiomyopathy in human patients, a mouse model was generated.

Methods

Mice carrying the alpha-actinin missense variant were generated by CRISPR-Cas9 genome editing. The heterozygous adult mice carrying the alpha-actinin variant were characterised by echocardiography and quantitative PCR. Hearts of homozygous embryos were analysed at E15.5 by high-resolution episcopic microscopy (HREM).

Results

Mice carrying a single copy of the missense variant were viable and had normal appearance. Adult heterozygous mice showed no signs of cardiomyopathy on echocardiography. However, mature male mice displayed molecular signs of cardiomyopathy, such as induction of the fetal gene programme at transcript level.

The attempt to generate adult mice homozygous for the variant failed: 9 breeding pairs produced 18 litters with 83 weaned pups, but no homozygous offspring. Embryonic lethality was confirmed and E15.5 was the latest stage homozygous pups were reliably found to be viable. At this timepoint, genotype distribution was within the expected Mendelian ratios.

HREM of the hearts at this stage revealed increased right ventricular chamber size and decreased left atrial size, when compared to wildtype littermates. Membranous ventricular septal defects were observed in 3 out of 8 homozygous hearts. Further these embryos displayed aortic stenosis and dysplasic leaflets of the pulmonary valve.

Conclusions

Heterozygous adult mice only displayed sub-clinical signs of disease. In contrast, the missense variant is embryonic lethal in the homozygous setting and leads to a range of morphological abnormalities in E15.5 hearts. Future work will identify how altered functions of alpha-actinin cause these changes.

Is the subdivision of Thy3 nodules needed? Audit reviewing the management of Thy3 nodules, and the associated malignancy rates

Introduction

Following the 2014 update to the BAETS thyroid nodule cytology guidance, the management of Thy3 lesions was modified by subdivision into Thy3a and Thy3f categories. Both lesions remain indeterminate but are proposed to have differing risks of malignancy when counselling patents: these risks have been called into question by subsequent data.

Methods

This, retrospective, Audit aimed to review the management of Thy3 (Thy3a and Thy3f) cytological diagnoses, within an NHS Trust, and compare this to the BAET Guidance 2014. Further, malignancy rates for Thy3a and Thy3f cytology were made over the calculated over the period.118 patients with a Thy3 cytology identified between 2014 and 2019. Data separated into data pre-2015 and 2015 onwards.

Results

In 2014, 29% of Thy3a nodules were managed in line with 2014 BAETS guidance. This improved to 34% from 2015. Meanwhile, Thy3f diagnoses were managed mostly in favour of the BAETS guidelines – 83% in 2014 and 92% 2015 onwards. The malignancy rates found, amongst all 118 patients, were 17.2% and 14.8% for Thy3f and Thy3a nodules respectively.

Conclusions

At this institution, Thy3 cytological diagnoses, regardless of classification into Thy3a or Thy3f, were largely treated in the same way (by a diagnostic hemi-thyroidectomy). The management of the nodules may reflect a variety of factors, including how comfortable patients and surgeons are when handling uncertainty. With malignancy rates for both Thy3a and Thy3f nodules being much the same, it is not surprising that they are managed in a similar way.

Acute Presentation of an unblocked Phaeochromocytoma with Small Bowel Ischaemia managed by Emergency Laparotomy and Adrenalectomy

Introduction

A 50-year-old male presented as an emergency with acute abdominal pain, reduced consciousness and blood pressure of 230/136mmHg, having felt unwell for a year. CT scans showed a 9cm right adrenal mass, a 27mm left ventricular thrombus and emboli to the distal superior mesenteric artery. Echocardiography demonstrated a reduced ejection fraction of 25%.

Methods

Our regional multidisciplinary team (Endocrinologists, Anaesthetists, Intensivists, Biochemists and Surgeons) utilised their experience to manage this challenging emergency, with supra-regional expert consultation.

Results

In ICU, intravenous phentolamine and unfractionated heparin infusions were given, attempting to avoid surgery until alpha blockade was established. The following day sepsis and peritonitis developed: surgery could no longer be deferred and had to be undertaken without blockade. After anaesthetic induction a 12 minute asystolic arrest ensued, but circulation was restored with CPR and bolus noradrenaline. Intraoperative photographs demonstrate 150cm of infarcted small bowel being resected, and sequential adrenalectomy being undertaken to avoid further catecholamine crisis and anaesthetic, as discussed with supra-regional colleagues. Post-arrest targeted temperature management was instigated alongside empirical steroid replacement. Serum metadrenaline fell from 58,495pmol/L (<510pmol/L) to 174pmol/L and normetadrenaline from 78,731pmol/L (<1180pmol/L) to 330pmol/L post-resection. Histological assessment confirmed phaeochromocytoma with malignant features (PASS=6 and GAPP=5). The patient made a full recovery and ejection fraction improved to 55%.

Conclusion

This case adds to the controversial equipoise regarding pre-operative blockade. An experienced multidisciplinary adrenal team was crucial in managing this life threatening combination. Noradrenaline was effective during cardiac arrest whilst the circulation was unresponsive to adrenaline.

Sex-differences and utility of treadmill testing in identification and genotype prediction in LQTS: a sub-study of the national LQTS registry and Canadian Hearts in Rhythm registry

Background/Purpose

Long-QT (LQT) Syndrome is an inherited heart rhythm condition presenting with QT-prolongation and failure to shorten with exercise, leading to life-threatening cardiac events. The prevalent normal-to-borderline phenotype remains a challenge for diagnosis. A three-step algorithm was developed to predict genotype from phenotypic characteristics with exercise testing. Sex-specific cut offs for determining a prolonged corrected QT value are 470ms for males and 480ms for females, serving as step 1 in the algorithm. The purpose of this study is to validate the algorithm using a national cohort that is more representative of the general LQT population, with a milder phenotype and more frequent ambiguity in phenotype.

Methods

A review of cases in the Canadian National Long-QT Registry, housed in the HiRO Registry was undertaken. Eligible cases from September 2014 to May 2020 were included. Gene-positive patients included 93 probands and 122 first-degree relatives (FDR) with a likely-pathogenic or pathogenic mutation according to ACMG criteria, limited to LQT1/2 subtypes, with 164 and 51 patients, respectively. Controls were composed of 39 gene-negative FDRs. Continuous variables were compared by the Mann-Whitney U test for 2-group comparisons, and Kruskal-Wallis test for multiple group comparisons. The predictive value of exercise ECG characteristics were analysed using ROC analysis and optimal cut-off values for exercise ECG characteristics (supine, standing, peak exercise, 1 and 4-minutes into recovery) were determined for males and females, using a sensitivity of 0.80 for carrier status and 0.75 for subtype.

Results

The 4-minute recovery QTc had the best predictive value for males, with an AUC of 0.86, and a cut-off point of 442ms given a sensitivity of 0.81 and specificity of 0.86. The 4-minute recovery QTc yielded an AUC of 0.79 for females, with a cut-off of 452ms given a sensitivity of 0.81 and specificity of 0.71. The 1-minute recovery QTc had the best predictive value for females, with an AUC of 0.92 and a cut-off point of 424ms given a sensitivity of 0.82 and specificity of 0.94. In prediction of LQT1, the 1-minute recovery QTc yielded the highest AUC for both males and females, at 0.68 and 0.80, respectively. Males had a cut off of 428ms with a sensitivity of 0.75 and specificity of 0.47, while females had a cut off of 451ms given a sensitivity of 0.76 and specificity of 0.75.

Conclusion

The current study demonstrates that exercise testing is a valid approach to diagnosing LQTS, with a differential optimal best measurement in males vs. females. Test performance measured by AUC was generally better at all time points in females compared to males. The algorithm is a reliable and simple method for the identification and prediction of genotype for probands and FDR carriers. The algorithm should be sex-stratified at the second step, with the 4-minute recovery QTc used for males and the 1-minute recovery QTc for females.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Canadian Institute of Health Research

619 Is the Subdivision of Thy3 Nodules Needed? An Audit Reviewing the Management of Thy3 Nodules, and the Associated Malignancy Rates

Introduction

Following the 2014 update to the BAETS thyroid nodule cytology guidance, the management of Thy3 lesions was modified by subdivision into Thy3a and Thy3f categories. Both lesions remain indeterminate but are proposed to have differing risks of malignancy when counselling patents: these risks have been called into question by subsequent data.

Aim

This Audit aimed to review the management of Thy3 (Thy3a and Thy3f) cytological diagnoses, within an NHS Trust, and compare this to the BAET Guidance 2014. Further, malignancy rates for Thy3a and Thy3f cytology were made over the calculated over the time period.

Method

A retrospective Audit looking at 118 patients with a Thy3 cytology identified between 2014 and 2019. Data separated into data pre-2015 and 2015 onwards.

Results

In 2014, 29% of Thy3a nodules were managed in line with 2014 BAETS guidance. This improved to 34% from 2015. Meanwhile, Thy3f diagnoses were managed mostly in favour of the BAETS guidelines – 83% in 2014 and 92% 2015 onwards. The malignancy rates found, amongst all 118 patients, were 17.2% and 14.8% for Thy3f and Thy3a nodules respectively.

Conclusions

At this institution, Thy3 cytological diagnoses, regardless of classification into Thy3a or Thy3f, were largely treated in the same way (by a diagnostic hemi-thyroidectomy). The management of the nodules may reflect a variety of factors, including how comfortable patients and surgeons are when handling uncertainty. With malignancy rates for both Thy3a and Thy3f nodules being much the same, it is not surprising that they are managed in a similar way.

1671 The Effect Of COVID-19 On the Management and Outcome of Neck of Femur Fractures in A District General Hospital - A Comparative Study

Aim

We wanted to see how the virus has impacted the management and outcome of our neck of femur fracture patients during Spring 2020.

Method

We performed a retrospective study of all neck of femur fracture patients presenting to our hospital from 23rd March 2020 (start of official lockdown in UK) until the end of May 2020 and compared them to patients presenting in the same time period in 2019. We recorded patient demographics, COVID-19 swab results, time to surgery, length of stay, transfers between wards, and 30-day mortality rates.

Results

We identified 75 patients in 2020 compared to 88 in 2019. Average length of stay was 11.4 days compared to 14.3 a year earlier. Mean time to surgery was 32.3 hours compared to 31.6 in 2019. The 30-day mortality increased significantly from 5.7% (5/88) in 2019 to 16% (12/75) in 2020 (p < 0.05) From 73 patients tested for COVID-19, 3 had a positive swab. Of these, 2 died. During their admission, 14 patients were transferred to 3 or more wards; in this group, 30-day mortality was 42.9% (6/14).

Conclusions

There has been a significant increase in 30-day mortality during COVID-19. Despite maintaining our time to surgery and reducing overall length of stay, we saw an increase in mortality, associated with multiple ward transfers rather than a high number of COVID-19 positive swab cases. Changes in pathways and wards configurations led to some patients requiring multiple transfers. This can cause difficulties in coordinated, multidisciplinary care for patients with NOF Fractures.

1085 Equestrian Related Pelvic and Acetabular Fractures – Experience from a Major Trauma Centre in England

Introduction

Equestrianism is enjoyed by three million people in the UK; however, there is a lack of literature on pelvic and acetabular (P&A) injuries incurred through the sport. We aim to describe P&A injuries sustained in equestrian accidents, discuss management, and establish their outcomes.

Method

Data was extracted from a prospectively collected database of referrals to the P&A Service of a Major Trauma Centre (MTC) from 01/01/2016 to 31/12/2020 and cross-referenced with medical records.

Results

60 of the 1,218 P&A referrals were secondary to horse-riding accidents. Mean age 45 (SD 16.59); 46 female; 33 managed non-operatively and 27 managed operatively at the MTC. There was sufficient information for 59 cases to be classified; 46 of the injuries were pelvic fractures (10 anterior-posterior compression; 29 lateral compression; 4 sacral and 3 pubic rami fractures) and 13 were acetabular (2 anterior column; 1 anterior wall; 2 associated both columns; 1 posterior column and posterior wall; 1 posterior wall; 2 T-shaped and 4 transverse fractures). The operative group were managed by examination under anaesthesia (n = 3), open reduction internal fixation (n = 22) or percutaneous fixation (n = 2). Mean hospitalisation was 9.2 days (SD 5.44). 81% were non-weight-bearing post-operatively and mean time to independent mobilisation was 12.6 weeks (SD 7.09). Return-to-riding information was available for 8 patients with a mean of 29.5 weeks (SD 11.55).

Conclusions

Equestrianism can result in significant P&A injuries. Patients should be counselled that they may have a long recovery, a protracted return-to-riding time and some may never return to the sport.

1514 Higher Mortality in Pelvic Acetabular Fractures Is Associated with Lower Body Mass Index

Aim

Fractures of the pelvis and acetabulum can be life-threatening or life changing injuries. Multiple factors can contribute to outcome including age, frailty, and baseline nutritional status. The aim of this study was to identify if low BMI (<18.5) was a predictor of outcome for patients with such injuries in terms of morbidity and mortality.

Method

We retrospectively analysed 1033 patients with pelvic or acetabular fractures referred to a single level 1 major trauma centre over a 4.5-year period (August 2015 - January 2020). Of these patients, 569 were admitted to the centre and included in our analysis. Data was collected on demographics, injury pattern, operative intervention, and complications. Comparison was made between patients that were underweight (BMI<18.5) and patients that were not, for in-hospital and post discharge complications including pulmonary embolus (PE), deep venous thrombosis (DVT), ileus, infection, loss of reduction and mortality at 6 months.

Results

Underweight patients had a statistically significant increase in mortality both in-hospital (p = 0.019) and at 6 months post injury (p = 0.039) when compared to other BMI groups. No statistical significance was found between these BMI groups comparing morbidity: DVT (p = 0.712), PE (p = 0.736) nor ileus (p = 0.149). Covariate analysis showed that a low BMI was associated with 3 times increased in-hospital mortality after correction for age and energy of injury (adjusted OR 3.028, 95% CI 1.059-8.659).

Conclusions

This study suggests increased mortality in patients with pelvic or acetabular fractures who are underweight. Surgeons should consider these findings in initiating appropriate peri-operative optimisation for these patients.

Pus Samples in Complicated Appendicitis: An Important Investigation or a Waste of Resources: A Prospective Cohort Study

BACKGROUND AND AIMS:

Appendicitis is a common presentation to hospital with appendectomy being the treatment of choice. Pre-operative administration of broad-spectrum antibiotics is common, but obtaining intra-abdominal pus samples is not. After an initial 6-month retrospective audit and departmental teaching on the importance of intra-peritoneal pus sampling, we aimed to determine whether intra-operative pus samples changed antibiotic management.

MATERIALS AND METHODS:

Following the initial audit cycle, a 6-month prospective cohort study was conducted. Clinical data were collected on a predetermined proforma to assess the effectiveness of the intervention and antibiotic prescribing practice. The data collected during the whole 1-year period was analyzed.

RESULTS:

During the 1-year period, 440 patients were identified as undergoing a laparoscopic procedure. After exclusion, 261 patients were identified as undergoing laparoscopic appendectomies, of which 141 (54%) were classified as complicated laparoscopic appendectomies. A total of 35 out of 141 (25%) pus samples were sent of which 24 (17%) resulted in positive cultures, with only nine of these positive cultures reported prior to the patient being discharged. No patient had their antibiotic regimen changed as a result of the culture results. There were three cases of cultures resistant to local antibiotics, but without significant clinical outcome. One of these patients developed a post-operative complication, but the antibiotic regimen was changed to broad spectrum rather than a specific antibiotic based on culture sensitivity. Of the 141 patients with complicated laparoscopic appendectomies, five (3.5%) developed post-operative complications: one readmission requiring a laparoscopic washout for pelvic collection, three (2%) cases of pelvic collections managed conservatively, and one case of prolonged paralytic ileus managed non-operatively.

CONCLUSION:

Overall, none of the patients with positive cultures had a change in prescribed antibiotics based on culture results. Hence, the routine practice of intra-peritoneal pus sampling following complicated appendicitis remains of little clinical value.

P90 A systematic review of spinal cord serum and cerebrospinal fluid biomarkers for use in degenerative cervical myelopathy

Objectives

Whilst radiological evidence of compression is the hallmark of degenerative cervical myelopathy [DCM], it is unable to stage or prognosticate. Moreover, asymptomatic spinal cord compression is common and therefore new methods of assessing spinal cord function are required. We aimed to: 1) Evaluate the evidence-base for serum and CSF biomarkers of spinal cord damage in diagnosis, prognosis or predicting response to treatment in DCM 2) Identify serum and CSF biomarkers of spinal cord damage studied in other conditions, which may have relevance to DCM.

Design

Scoping review.

Subjects

Human only.

Methods

A search of MEDLINE and EMBASE was performed. Studies involving DCM patients or biomarkers relevant to spinal cord pathobiology were included.

Results

852 results were screened, of which 83 were included. 9 studies explored 12 biomarkers in DCM. NFH (n=3), S100b and NSE (n=2) received most study. 74 studies explored a further 118 biomarkers in other conditions; S100b (n=13), NFH (n=11) and GFAP (n=10) received most study. Overall, 72 studies used targeted approaches, in which candidate biomarkers were chosen in advance. 11 used unbiased approaches, in which high throughput analyses identified candidate biomarkers during the study.

Conclusions

The evidence-base for use of biomarkers in DCM is limited. Whilst targeted approaches have identified a number of candidate spinal cord markers, few have shown clinical utility. There is a shift towards investigating panels of multiple markers and unbiased, high-throughput approaches.

Evaluating the Validity of a Bayesian Program for Predicting Stage in Hodgkin’s Disease

A Bayesian model that provides probabilistic information about the spread of malignancy in a Hodgkin’s disease patient has been developed at the Tufts New England Medical Center. In assessing the model’s reliability, it seemed important to use it to make predictions about patients other than those relevant to its construction. The accuracy of these predictions could then be tested statistically. This paper describes such a test, based on 243 Hodgkin’s disease patients of known pathologic stage. The results obtained were supportive of the model, and the test procedure might interest those wishing to determine whether the imperfections that attend any attempt to make probabilistic forecasts have gravely damaged their accuracy.

Relationship Between Sarcopenia and Frailty in the Toledo Study of Healthy Aging: A Population Based Cross-Sectional Study

INTRODUCTION

Frailty and sarcopenia are correlates of musculoskeletal aging that represent a state of vulnerability increasing the risk of negative health outcomes. Standardized definitions are lacking for both, and sometimes both concepts are used interchangeably. However, no large study has assessed the coexistence of these 2 entities in a cohort of older community-dwelling people.

METHODS

Data were taken from the Toledo Study of Healthy Aging (TSHA), a study of community-dwelling elderly (≥65 years). The study population consists of 1611 participants with frailty and sarcopenia assessments. For sarcopenia, we used 3 criteria: European Working Group on Sarcopenia in Older People (EWGSOP), the Foundation for the National Institutes of Health (FNIH), and the FNIH fitted to the cut-off points of our population [standardized FNIH (sFNIH)]. Frailty was assessed according to the Fried criteria with cut-off points adjusted to our population. We used logistic regression to assess the relationship between sarcopenia and frailty and measures of diagnostic accuracy to evaluate the potential use of sarcopenia as a diagnostic marker for frailty.

RESULTS

The mean age of the population was 75.42 years (±5.86). Overall, 72 (4.5%) were frail. In addition, 352 (21.8%), 332 (20.6%), and 453 (28.1%) participants were considered sarcopenic according to the EWGSOP, FNIH, and sFNIH criteria, respectively. The prevalence of frailty among those with sarcopenia was 8.2% (29/352), 15.7% (52/332), and 10.4% (47/453). Moreover, among frail people, the prevalence of sarcopenia was 40.27%, 72.2%, and 65.3% according to the used criteria. Sarcopenia showed a low sensitivity (<10%) but high specificity (>97%) for the diagnosis of frailty, with a low intercorrelation (Cramer V = 0.16, 0.40, and 0.30) between the 3 criteria and frailty. Using multivariate logistic regression, frailty was associated with sarcopenia according to EWGSOP [odds ratio (OR) = 1.67, 95% confidence interval (CI) = 0.95, 2.96], FNIH (OR = 10.61, 95% CI = 5.8, 19.4), and sFNIH (OR = 6.63, 95% CI =3.5, 12.53).

CONCLUSION

Frailty and sarcopenia are distinct but related conditions. Sarcopenia is not a useful clinical biomarker of frailty, but its absence might be useful to exclude frailty.

The Last Glacial Maximum and deglaciation in central Patagonia, 44°S–49°S

This paper reviews published geochronological data on glacier fluctuations and environmental changes in central Patagonia (44° S - 49° S) from the Last Glacial Maximum (LGM) through to the Holocene. Well-dated glacial chronologies from the southern mid-latitudes can inform on the synchronicity of glacial advances worldwide and provide insight on the drivers of southern hemisphere glaciations. In central Patagonia, two large outlet lobes of the former Patagonian Ice Sheet advanced in broad synchrony with the global LGM. In contrast to other parts of Patagonia, there is no convincing evidence for a more extensive local LGM advance during Marine Isotope Stage 3. Deglaciation initiated at ca. 19 ka, earlier than in other parts of Patagonia and regionally in the Southern Hemisphere, and rapid deglaciation saw ice margins retreat in places by at least 80-120 km within a few millennia. The Lateglacial glacier margins are poorly constrained, but an ice mass substantial enough to maintain a large regional proglacial lake must have persisted at this time. The timing of lake drainage and opening of the Río Baker drainage route to the Pacific Ocean is debated; the only directly dated shoreline suggests this occurred at the end of the Antarctic Cold Reversal at 12.7 ka. Palaeoecological evidence for cooling during the Antarctic Cold Reversal or Younger Dryas remains equivocal, which may reflect both the eurythermic nature of Patagonian vegetation and shifting Southern Westerly Winds. Eastern outlet glaciers appear to have advanced or stabilised at the Lateglacial/Holocene transition when palaeoenvironmental records indicate warmer and drier conditions, but the reason for this is unclear. Our review reveals both spatial and temporal gaps in available data that provide avenues for future research.

Can laparoscopy be part of a paediatric surgery outreach service?

INTRODUCTION The aim of this study was to assess the outreach laparoscopic service delivered by four paediatric surgeons to a district general hospital (DGH). METHODS A retrospective review was carried out of all laparoscopic procedures performed in a single DGH between January 2004 and November 2014 by the four paediatric surgeons providing the outreach service. All operations were identified from the electronic theatre system and archived correspondence. Demographic and clinical details were obtained from contemporaneous records. RESULTS Over the 11-year study period, 1,339 operations were performed as part of the outreach paediatric surgery service, with 128 patients (9.6%) undergoing laparoscopy. The indications for laparoscopic surgery were impalpable unilateral or bilateral undescended testes (UDT) (n=79, 62%) or request for insertion of a feeding gastrostomy (n=49, 38%). All but six UDT cases (96%) were performed as day surgery and the median length of stay for gastrostomy patients was 3 days (interquartile range: 2-3 days). There were three UDT cases with surgical complications and one had complications related to the anaesthesia. One gastrostomy case required transfer to our tertiary centre for management of postoperative urinary retention and urethral injury. CONCLUSIONS Elective laparoscopic procedures in young children can be provided safely as components of an outreach paediatric surgery service in a DGH setting as part of an increasing volume of operations performed by specialist paediatric surgeons. This enables children to have a high quality service as close to their home as possible.

Cutting Edge: Tissue-Resident Memory T Cells Generated by Multiple Immunizations or Localized Deposition Provide Enhanced Immunity

Tissue-resident memory T cells (T_RM) have been shown to afford superior protection against infection, particularly against pathogens that enter via the epithelial surfaces of the body. Although T_RM are often concentrated at sites of prior infection, it has been shown that T_RM can disseminate throughout the body. We examined the relative effectiveness of global versus targeted CD8⁺ T_RM lodgment in skin. The site of initial T cell priming made little difference to skin lodgement, whereas local inflammation and Ag recognition enhanced T_RM accumulation and retention. Disseminated T_RM lodgment was seen with the skin, but required multiple exposures to Ag and was inferior to targeted strategies. As a consequence, active recruitment by inflammation or infection resulted in superior T_RM numbers and maximal protection against infection. Overall, these results highlight the potency of localized T_RM deposition as a means of pathogen control as well as demonstrating the limitations of global T_RM lodgment.

Preliminary Results of PTFE Patch Saphenoplasty to Prevent Neovascularization Leading to Recurrent Varicose Veins

Objective:

Recurrence is common after varicose vein surgery. Neovascularization may be one cause of recurrent veins. This was a study of PTFE patch saphenoplasty to try and prevent recurrent veins.

Design and setting:

Prospective cohort study of patients treated in a vascular surgical unit.

Patients and interventions:

Fifty patients having surgery for symptomatic long saphenous varicose veins (66 legs, 51 primary and 15 recurrent veins) had a PTFE patch sutured over the saphenous opening after flush saphenofemoral ligation.

Main outcome measures:

The rate of varicose vein recurrence and neovascularization 1 year after surgery were determined using clinical examination and venous duplex imaging.

Results:

Forty patients (80%) remained pleased with the results of their surgery. Recurrent veins were visible in 14 (21%) legs: 10 were principally due to neovascularization, two to sapheno-popliteal incompetence and two to an incompetent mid-thigh perforating vein. Three other legs had neovascularization but no recurrent veins. Both recurrent veins (47% versus 14%) and neovascularization (40% versus 14%) were significantly more common in patients having surgery for recurrent veins.

Conclusions:

PTFE patching was safe but did not abolish neovascularization. Neovascularization was the principal cause of recurrent veins in this study and perseverance with investigations into other barrier methods is worthwhile.

Emergency readmissions to paediatric surgery and urology: The impact of inappropriate coding

Introduction In England, emergency readmissions within 30 days of hospital discharge after an elective admission are not reimbursed if they do not meet Payment by Results (PbR) exclusion criteria. However, coding errors could inappropriately penalise hospitals. We aimed to assess the accuracy of coding for emergency readmissions. Methods Emergency readmissions attributed to paediatric surgery and urology between September 2012 and August 2014 to our tertiary referral centre were retrospectively reviewed. Payment by Results (PbR) coding data were obtained from the hospital's Family Health Directorate. Clinical details were obtained from contemporaneous records. All readmissions were categorised as appropriately coded (postoperative or nonoperative) or inappropriately coded (planned surgical readmission, unrelated surgical admission, unrelated medical admission or coding error). Results Over the 24-month period, 241 patients were coded as 30-day readmissions, with 143 (59%) meeting the PbR exclusion criteria. Of the remaining 98 (41%) patients, 24 (25%) were inappropriately coded as emergency readmissions. These readmissions resulted in 352 extra bed days, of which 117 (33%) were attributable to inappropriately coded cases. Conclusions One-quarter of non-excluded emergency readmissions were inappropriately coded, accounting for one-third of additional bed days. As a stay on a paediatric ward costs up to £500 a day, the potential cost to our institution due to inappropriate readmission coding was over £50,000. Diagnoses and the reason for admission for each care episode should be accurately documented and coded, and readmission data should be reviewed at a senior clinician level.

Should an increase in cerebral neurochemicals following head kicks in full contact karate influence return to play?

Background:

Cerebral neurochemicals are markers of traumatic brain injury (TBI).

Objectives:

The aim of the study was to determine whether kicks to the head (KTH) in full contact karate significantly increased serum concentrations of protein S-100B, and neurone specific enolase (NSE). Kicks to the body (KTB) were also quantified to asses muscle tissue injury. Muscle damage was assessed by analysis of serum total creatine kinase (CK).

Methods:

Twenty-four full contact karate practitioners were observed and filmed during actual competition and divided into two main groups post event: (1) Kicks to the head and body group (KTH): n = 12; mean ± SD; age, 30.4 ± 6.7 years; height, 1.74 ± 0.1 m; weight, 79.1 ± 2.1 kg; and (2): Kicks to the body group (KTB): n = 12; mean ± SD; age, 28.2 ± 6.5 years; height, 1.75 ± 0.1 m; weight, 79.2 ± 1.7 kg. The KTH group received direct kicks to the head, while group KTB received kicks and punches to the body. Blood samples were taken before and immediately post-combat for analysis of serum S-100B, NSE, CK and cardiac troponin.

Results:

Significant increases in serum concentrations of S-100B (0.12 ± 0.17 vs. 0.37 ± 0.26, µg.L−1) and NSE (11.8 ± 4.1 vs. 20.2 ± 9.1 ng.mL−1) were encountered after combat in the KTH group and CK (123 ± 53 vs. 184 ± 103 U.L−1) in the KTB group (all P <0.05).

Conclusions:

Head kicks in full contact karate cause elevation of neurochemical markers associated with damaged brain tissue. The severity of injury is related to the early post-traumatic release of protein S-100B and NSE. The early kinetics and appearance post injury can reflect intracranial pathology, and suggest S-100B and NSE are extremely sensitive prognostic markers of TBI.

A Review of Forensic Science Management Literature

The science in forensic science has received increased scrutiny in recent years, but interest in how forensic science is managed is a relatively new line of research. This paper summarizes the literature in forensic science management generally from 2009 to 2013, with some recent additions, to provide an overview of the growth of topics, results, and improvements in the management of forensic services in the public and private sectors. This review covers only the last three years or so and a version of this paper was originally produced for the 2013 Interpol Forensic Science Managers Symposium and is available at interpol.int.

Porous and strong three-dimensional carbon nanotube coated ceramic scaffolds for tissue engineering

A method to coat high-quality uniform coatings of carbon nanotubes throughout 3D porous structures is developed. Testing of their physical and biological properties demonstrate their potential for application in tissue engineering.