Neutrophil Gelatinase-associated Lipocalin as a Marker of Postoperative Acute Kidney Injury Following Cardiac Surgery in Patients with Preoperative Kidney Impairment

INTRODUCTION

Acute kidney injury (AKI) is a serious complication of cardiac surgery. The current 'gold standard' for determining AKI is change in serum creatinine and urine output, however, this change occurs relatively late after the actual injury occurs. Identification of new biomarkers that detect early AKI is required. Recently, new biomarkers, such as the NephroCheck® Test and AKIRisk have also been tested and found to be good indicators of AKI. Neutrophil gelatinase-associated lipocalin (NGAL) has shown promise in paediatric patients but has displayed varied results in adult populations, particularly post cardiac surgery. The aim of this study was to assess the value of urinary NGAL as a biomarker of AKI in patients with pre-existing renal impairment (eGFR >15ml/min to eGFR<60ml/min).

METHODS

A post-hoc analysis of urinary NGAL concentrations from 125 patients with pre-existing kidney impairment, who participated in a randomised trial of haemofiltration during cardiac surgery, was undertaken. Urinary NGAL was measured using ELISA at baseline, post-operatively and 24 and 48 hours after surgery, and serum creatinine was measured pre and postoperatively and then at 24, 48, 72 and 96 hours as routine patient care. NGAL concentrations were compared in patients with and without AKI determined by changes in serum creatinine concentrations. A Kaplan-Meier plot compared survival for patients with or without AKI and a Cox proportional hazards analysis was performed to identify factors with the greatest influence on survival.

RESULTS

Following surgery, 43% of patients developed AKI (based on KDIGO definition). Baseline urinary NGAL was not found to be significantly different between patients that did and did not develop AKI. Urinary NGAL concentration was increased in all patients following surgery, regardless of whether they developed AKI and was also significant between groups at 24 (p=0.003) and 48 hours (p<0.0001). Urinary NGAL concentrations at 48 hours correlated with serum creatinine concentrations at 48 hours (r=0.477, p<0.0001), 72 hours (r=0.488, p<0.0001) and 96 hours (r=0.463, p<0.0001). Urinary NGAL at 48 hours after surgery strongly predicted AKI (AUC=0.76; P=0.0001). A Kaplan- Meier plot showed that patients with postoperative AKI had a significantly lower 7-year survival compared with those without AKI. Postoperative urinary NGAL at 48 hours >156ng/mL also strongly predicted 7-year survival. However, additive EuroSCORE, age, current smoking and post-operative antibiotics usage were distinctly significantly more predictive of 7-year survival as compared with postoperative urinary NGAL at 48 hours >156ng/mL.

CONCLUSIONS

Our study demonstrated that postoperative urinary NGAL levels at 48 hours postsurgery strongly predicts the onset or severity of postoperative AKI based on KDIGO classification in patients with preoperative kidney impairment and were also strongly related to 7-year survival.

Capsid Engineering Overcomes Barriers Toward Adeno-Associated Virus Vector-Mediated Transduction of Endothelial Cells

Endothelial cells (EC) are targets in gene therapy and regenerative medicine, but they are inefficiently transduced with adeno-associated virus (AAV) vectors of various serotypes. To identify barriers hampering efficient transduction and to develop an optimized AAV variant for EC transduction, we screened an AAV serotype 2-based peptide display library on primary human macrovascular EC. Using a new high-throughput selection and monitoring protocol, we identified a capsid variant, AAV-V_EC, which outperformed the parental serotype as well as first-generation targeting vectors in EC transduction. AAV vector uptake was improved, resulting in significantly higher transgene expression levels from single-stranded vector genomes detectable within a few hours post-transduction. Notably, AAV-V_EC transduced not only proliferating EC but also quiescent EC, although higher particle-per-cell ratios had to be applied. Also, induced pluripotent stem cell-derived endothelial progenitor cells, a novel tool in regenerative medicine and gene therapy, were highly susceptible toward AAV-V_EC transduction. Thus, overcoming barriers by capsid engineering significantly expands the AAV tool kit for a wide range of applications targeting EC.

Comparison of high-flow oxygen therapy with standard oxygen therapy for prevention of postoperative pulmonary complications after major head and neck surgery involving insertion of a tracheostomy: a feasibility study

Major operations on the head and neck that involve microvascular reconstruction and a tracheostomy are prolonged procedures with considerable postoperative risk. Postoperative pulmonary complications are common because of mechanical ventilation, immobility, and inadequate humidification. High-flow heated oxygen therapy (HFOT) may overcome some of these issues, but we know of no published studies to support its use. The aim of this single-site randomised controlled trial therefore was to explore its feasibility and safety in these patients. Twenty patients were randomised to have HFOT (10 patients) or standard oxygen therapy (10 patients). HFOT was used from cessation of mechanical ventilation until decannulation of the tracheostomy. The primary outcome was feasibility. The secondary outcome measures explored the incidence of postoperative pulmonary complications, achievement of milestones of weaning from the tracheostomy, and hospital length of stay. A total of 21 patients were consecutively recruited and all provided informed consent. One who did not require a tracheostomy was later excluded. All patients initially had the intervention as planned, and one was electively changed to the control group because of discomfort caused by the high-flow oxygen. There were no adverse events or safety concerns in either group. Secondary outcomes showed a reduction in the incidence of pulmonary complications in the HFOT group. The use of HFOT is safe and feasible in patients who have microvascular reconstruction of the head and neck and a tracheostomy.

Staphylococcus aureus colonization and acquisition of skin and soft tissue infection among Royal Marines recruits: a prospective cohort study

OBJECTIVES

Skin and soft tissue infections (SSTIs) are a serious health issue for military personnel. Of particular importance are those caused by methicillin-resistant Staphylococcus aureus and Panton-Valentine leucocidin (PVL)-positive S. aureus (PVL-SA), as they have been associated with outbreaks of SSTIs. A prospective observational study was conducted in Royal Marine (RM) recruits to investigate the prevalence of PVL-SA carriage and any association with SSTIs.

METHODS

A total of 1012 RM recruits were followed through a 32-week training programme, with nose and throat swabs obtained at weeks 1, 6, 15 and 32. S. aureus isolates were characterized by antibiotic susceptibility testing, spa typing, presence of mecA/C and PVL genes. Retrospective review of the clinical notes for SSTI acquisition was conducted.

RESULTS

S. aureus colonization decreased from Week 1 to Week 32 (41% to 26%, p < 0.0001). Of 1168 S. aureus isolates, three out of 1168 (0.3%) were MRSA and ten out of 1168 (0.9%) PVL-positive (all MSSA) and 169 out of 1168 (14.5%) were resistant to clindamycin. Isolates showed genetic diversity with 238 different spa types associated with 25 multi-locus sequence type (MLST) clonal complexes. SSTIs were seen in 35% (351/989) of recruits with 3 training days lost per recruit. SSTI acquisition rate was reduced amongst persistent carriers (p < 0.0283).

CONCLUSIONS

Nose and throat carriage of MRSA and PVL-SA was low among recruits, despite a high incidence of SSTIs being reported, particularly cellulitis. Carriage strains were predominantly MSSA with a marked diversity of genotypes. Persistent nose and/or throat carriage was not associated with SSTI acquisition. Putative person-to-person transmission within troops was identified based on spa typing requiring further research to confirm and explore potential transmission routes.

Perceptions and psychosocial impact of food, nutrition, eating and drinking in people with inflammatory bowel disease: a qualitative investigation of food-related quality of life

INTRODUCTION

Extensive research has provided an important understanding of the impact of inflammatory bowel disease (IBD) on nutrient intake, requirements and metabolism. By contrast, there has been limited research examining the psychosocial aspects of food, eating and drinking in IBD. The present study aimed to address this unmet need.

METHODS

Qualitative semi-structured interviews regarding the perceptions and psychosocial impact of food, eating and drinking were undertaken with 28 purposively selected people with IBD. Interviews were audio-recorded and transcribed verbatim. Colaizzi's framework was used to structure the data analysis.

RESULTS

Five major themes were identified. IBD symptoms and both surgical and medical treatments were described as having a direct impact on eating and drinking, with participants also using different food-related strategies to control IBD symptoms. These included a process of experimentation to identify trigger foods, following a severely restricted and limited diet, eating small portions, and eating more frequently. However, their limited knowledge about if, and how, food affected their symptoms, often resulted in negative coping strategies that impacted on psychosocial functioning, including a lack of enjoyment of eating, being afraid to eat and finding social occasions stressful. Managing food and drinking also made food shopping and preparation more burdensome, creating problems with families, at work and for social life, as well as the need for careful preparation and advanced planning of activities.

CONCLUSIONS

Inflammatory bowel disease has a profound impact on psychosocial aspects of food and nutrition, which impacts on 'food-related quality of life' (FRQoL). Further research is required to identify interventions that will improve FRQoL in patients with IBD.

Session 2: Extramural vascular invasion and extranodal deposits: should they be treated the same?

Professor Nagtegaal has already highlighted that lymph nodes are probably not responsible for the development of liver metastases. If they are not, then is there another mechanism? Professor Haboubi addresses the question of extranodal deposits - their frequency and their importance in the development of metastatic disease. The experts review the evidence and discuss whether this information will alter treatment decisions and staging systems in the future.

Measuring oral health impact among care home residents in Wales

Objective

To explore inequalities in oral health impact among care home residents using OHIP-14 and ADHS criteria.

Basic research design

Cross-sectional survey with structured interview and clinical examination using 2009 ADHS criteria including OHIP-14. Comparisons were made between groups of residents and with findings from the ADHS 2009.

Participants

Care homes and residents were randomly selected. Those without capacity and non-English/Welsh speakers were excluded. 447 residents answered all OHIP-14 questions and had full oral examination.

Main Outcome Measure

OHIP-14.

Results

Reporting of OHIP problems was more common among care home residents compared with older people examined in the ADHS 2009 (50% vs 40%). There was no difference in the mean number of impacts between residents who were: dentate/edentate; denture wearing/non-denture wearing; with/without caries. Residents reporting 'problems and pain in your mouth at the moment', or 'occasional or more frequent dry mouth', more often experienced OHIP-14 impacts.

Conclusion

Compared with peers living in the community, both dentate and edentate care home residents are more likely to live with one or more impacts. Two simple questions related to 'Any problems and pain in your mouth?' and 'Do you have frequent dry mouth?' may help to target care home residents more likely to experience oral health impacts.

Cultural competency and communication skills of dental students: clinical supervisors' perceptions

OBJECTIVES

This study explored clinical supervisor's (CS) views and experiences of dental students' cultural competence (CC) at the Melbourne Dental School, The University of Melbourne, Australia. Additionally, this study explored CS insights into how CC could be taught.

METHODS

Semi-structured one-to-one interviews were organised with consenting CS. Interview topics included the following: the importance of CC, communication and rapport, the role of culture in oral health and the need for curriculum enhancement. Interviews were recorded, transcribed and thematically analysed to identify key areas using NVivo software.

RESULTS

A total of 12 CS participated in this study. CS acknowledged the importance of CC and felt that it was important for good patient management. CS's definition of CC focused primarily on language and communication skills. CS felt that dental students were generally able to manage culturally diverse patients. However, CS indicated that additional training in this area would be beneficial. Concerns were raised about the students' ability to establish good rapport and communication, with CS highlighting areas such as misuse of interpreters and use of jargon. CS felt that clinical experience, confidence and a positive attitude are effective tools for overcoming cultural barriers. Furthermore, some CS also felt that cultural competency was a skill that is learnt through experience.

CONCLUSIONS

For most CS, cultural competence was an important part of the clinician-patient exchange which would benefit from enhanced curriculum. They also highlighted areas where transcultural education could be improved. The majority of CS believed dental students managed culturally diverse patients well.

Assessment of Minimum Important Difference and Substantial Clinical Benefit with the Vascular Quality of Life Questionnaire-6 when Evaluating Revascularisation Procedures in Peripheral Arterial Disease

OBJECTIVES

Patient reported outcomes are increasingly used to assess outcomes after peripheral arterial disease (PAD) interventions. VascuQoL-6 (VQ-6) is a PAD specific health-related quality of life (HRQoL) instrument for routine clinical practice and clinical research. This study assessed the minimum important difference for the VQ-6 and determined thresholds for the minimum important difference and substantial clinical benefit following PAD revascularisation.

MATERIALS AND METHODS

This was a population-based observational cohort study. VQ-6 data from the Swedvasc Registry (January 2014 to September 2016) was analysed for revascularised PAD patients. The minimum important difference was determined using a combination of a distribution based and an anchor-based method, while receiver operating characteristic curve analysis (ROC) was used to determine optimal thresholds for a substantial clinical benefit following revascularisation.

RESULTS

A total of 3194 revascularised PAD patients with complete VQ-6 baseline recordings (intermittent claudication (IC) n = 1622 and critical limb ischaemia (CLI) n = 1572) were studied, of which 2996 had complete VQ-6 recordings 30 days and 1092 a year after the vascular intervention. The minimum important difference 1 year after revascularisation for IC patients ranged from 1.7 to 2.2 scale steps, depending on the method of analysis. Among CLI patients, the minimum important difference after 1 year was 1.9 scale steps. ROC analyses demonstrated that the VQ-6 discriminative properties for a substantial clinical benefit was excellent for IC patients (area under curve (AUC) 0.87, sensitivity 0.81, specificity 0.76) and acceptable in CLI (AUC 0.736, sensitivity 0.63, specificity 0.72). An optimal VQ-6 threshold for a substantial clinical benefit was determined at 3.5 scale steps among IC patients and 4.5 in CLI patients.

CONCLUSIONS

The suggested thresholds for minimum important difference and substantial clinical benefit could be used when evaluating VQ-6 outcomes following different interventions in PAD and in the design of clinical trials.

What proportion of caries into dentine at age 5 is present at age 3?

OBJECTIVE

To explore the proportion of decay at age 5 in Wales presenting by and after age 3 years from geographical and deprivation perspectives.

BASIC RESEARCH DESIGN

Retrospective analysis of data from independent cross-sectional studies of 3-year-olds in early 2013 and 5-year-olds in school year 2014/5. This includes novel graphical presentation of caries at age 3 and estimated 3-5 caries increment at age 5.

SETTING AND PARTICIPANTS

NHS oral health surveillance programme in Wales examining children in nurseries at age 3 and in schools two years later.

MAIN OUTCOME MEASURES

%d₃mft⟩0 at ages 3 and 5 years, plus estimated 3-5 caries increments for these two indices. Data are analysed using index of deprivation and Health Board population density (as a proxy for rurality).

RESULTS

In most Health Boards and all deprivation quintiles there is a larger proportion of caries into dentine presenting between ages 3-5 than by age 3. In rural Health Boards the proportion of caries present by age 3 is much smaller. In one Health Board more caries presents by age 3 than after. In rural Health Boards the current prevention activity has potential to push reported caries prevalence at age 5 below 10%. In urban Health Boards action by age 5 will be required to push caries prevalence significantly below 20%.

CONCLUSIONS

Findings from this analysis suggest need for earlier prevention activity in some Health Boards in Wales.

A phase 2, randomized, double-blind, placebo- controlled study of chemo-immunotherapy combination using motolimod with pegylated liposomal doxorubicin in recurrent or persistent ovarian cancer: a Gynecologic Oncology Group partners study

BACKGROUND

A phase 2, randomized, placebo-controlled trial was conducted in women with recurrent epithelial ovarian carcinoma to evaluate the efficacy and safety of motolimod-a Toll-like receptor 8 (TLR8) agonist that stimulates robust innate immune responses-combined with pegylated liposomal doxorubicin (PLD), a chemotherapeutic that induces immunogenic cell death.

PATIENTS AND METHODS

Women with ovarian, fallopian tube, or primary peritoneal carcinoma were randomized 1 : 1 to receive PLD in combination with blinded motolimod or placebo. Randomization was stratified by platinum-free interval (≤6 versus >6-12 months) and Gynecologic Oncology Group (GOG) performance status (0 versus 1). Treatment cycles were repeated every 28 days until disease progression.

RESULTS

The addition of motolimod to PLD did not significantly improve overall survival (OS; log rank one-sided P = 0.923, HR = 1.22) or progression-free survival (PFS; log rank one-sided P = 0.943, HR = 1.21). The combination was well tolerated, with no synergistic or unexpected serious toxicity. Most patients experienced adverse events of fatigue, anemia, nausea, decreased white blood cells, and constipation. In pre-specified subgroup analyses, motolimod-treated patients who experienced injection site reactions (ISR) had a lower risk of death compared with those who did not experience ISR. Additionally, pre-treatment in vitro responses of immune biomarkers to TLR8 stimulation predicted OS outcomes in patients receiving motolimod on study. Immune score (tumor infiltrating lymphocytes; TIL), TLR8 single-nucleotide polymorphisms, mutational status in BRCA and other DNA repair genes, and autoantibody biomarkers did not correlate with OS or PFS.

CONCLUSIONS

The addition of motolimod to PLD did not improve clinical outcomes compared with placebo. However, subset analyses identified statistically significant differences in the OS of motolimod-treated patients on the basis of ISR and in vitro immune responses. Collectively, these data may provide important clues for identifying patients for treatment with immunomodulatory agents in novel combinations and/or delivery approaches.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT 01666444.