Rifampicin-resistant TB: discordance between Xpert® MTB/RIF and MTBDRplus results

BACKGROUND: South Africa´s diagnostic algorithm for TB diagnosis from 2011 to 2017 employed the Xpert^® MTB/RIF assay as the initial screening test for TB diagnosis and rifampicin (RIF) susceptibility, followed by submission of a specimen for GenoType^® MTBDRplus. This study aimed to determine the concordance between the two assays in terms of RIF susceptibility and explore reasons for discordance.METHODS: This was a retrospective laboratory-based study that included all MTBDRplus results of tests performed at the Braamfontein Mycobacteriology Referral Laboratory between 1 September 2014 and 31 August 2015. The patient´s Xpert RIF result was linked with the MTBDRplus result.RESULTS: The overall concordance between RIF susceptibility results was 96.4%. There were 68 discordant RIF results. The most common reasons for discordance identified were possible false Xpert RIF-resistant results (22%), mixed infection/heteroresistance (16%), transcription errors (7%) and erroneous manual interpretation of the MTBDRplus strip (7%). Xpert RIF resistance detected using delayed hybridisation was associated with discordance.CONCLUSIONS: The overall concordance between the MTBDRplus and Xpert RIF results were very good. Management of discordance should include repeat specimens for Xpert and MTBDRplus and rpoB sequencing. All variables should then be considered before treatment regimens are altered.

Assessing trace-elements as indicators of marine finfish aquaculture across three distinct Canadian coastal regions

Several trace-elements have been identified as indicators of finfish aquaculture organic enrichment. In this study, sediment sampling at finfish farms was completed as part of an Aquaculture Monitoring Program in three distinct Canadian regions. Despite diverse datasets, multivariate analyses show a consistent clustering of known direct (Cu and Zn) and indirect (Cd, Mo and U) tracers of aquaculture activities with sediment organic matter (OM) and/or total dissolved sulfides concentrations. OM content was also a predictor of Cu, Zn, Mo and U concentrations according to decision tree analyses. Distance from cages did not emerge as a strong driver of differences among sampling points; however, a tendency towards negative associations is clear especially for Zn. Enriched stations as determined after geochemical normalization were mostly localized within 150 m of net-pens. Selected trace-elements (in particular Zn) can be useful indicators of aquaculture organic enrichment in different ecosystems and valuable tools for monitoring programs.

O40 Predictive models of individual risk of elective caesarean section complications: a systematic review

Introduction

With increasing caesarean section (c-section) rates, personalised communication of risk has become paramount. A reliable tool to predict complications would support evidence-based discussion around planned mode of birth.

Method

MEDLINE, Embase, Web of Science, CINAHL, and the Cochrane Library were searched on 27th January with the terms relating to c-section, prognostic models, and complications such as infection. Any study developing and/or validating a prognostic model for maternal complications of c-section in the English language after January 1995 was included. Data extracted encompassed: source of data, participant criteria, outcome to be predicted, candidate predictors, actual predictors, sample size, model development, and model performance. PROBAST (Prediction model Risk Of Bias Assessment Tool) was utilised for risk of bias analysis and applicability concern in the prognostic model studies.

Result

7,752 studies were identified, of which 16 were reviewed producing 3 studies where 3 prognostic models were identified which predicted risk of: blood transfusion, spinal hypotension, and postpartum haemorrhage. From the 3 studies, a total of 29 unique candidate predictors were identified and 15 predictors in the final model. Study authors deemed their studies to be exploratory, exploratory, and confirmatory respectively. None were externally validated and all had a high risk of bias due to analysis technique.

Conclusion

Few models have been developed to predict complications of elective c-section. Existing models predicting blood transfusion, spinal hypotension, and postpartum haemorrhage cannot be recommended for clinical practice. Future research should focus on identifying predictors known before surgery and validating resulting models.

Take-home Message

Systematic review of prediction models for planned C-section complications found none suitable for practice.

Cervical ripening at home or in-hospital-prospective cohort study and process evaluation (CHOICE) study: a protocol

INTRODUCTION

The aim of the cervical ripening at home or in-hospital-prospective cohort study and process evaluation (CHOICE) study is to compare home versus in-hospital cervical ripening to determine whether home cervical ripening is safe (for the primary outcome of neonatal unit (NNU) admission), acceptable to women and cost-effective from the perspective of both women and the National Health Service (NHS).

METHODS AND ANALYSIS

We will perform a prospective multicentre observational cohort study with an internal pilot phase. We will obtain data from electronic health records from at least 14 maternity units offering only in-hospital cervical ripening and 12 offering dinoprostone home cervical ripening. We will also conduct a cost-effectiveness analysis and a mixed methods study to evaluate processes and women/partner experiences. Our primary sample size is 8533 women with singleton pregnancies undergoing induction of labour (IOL) at 39+0 weeks' gestation or more. To achieve this and contextualise our findings, we will collect data relating to a cohort of approximately 41 000 women undergoing IOL after 37 weeks. We will use mixed effects logistic regression for the non-inferiority comparison of NNU admission and propensity score matched adjustment to control for treatment indication bias. The economic analysis will be undertaken from the perspective of the NHS and Personal Social Services (PSS) and the pregnant woman. It will include a within-study cost-effectiveness analysis and a lifetime cost-utility analysis to account for any long-term impacts of the cervical ripening strategies. Outcomes will be reported as incremental cost per NNU admission avoided and incremental cost per quality adjusted life year gained.

RESEARCH ETHICS APPROVAL AND DISSEMINATION

CHOICE has been funded and approved by the National Institute of Healthcare Research Health Technology and Assessment, and the results will be disseminated via publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ISRCTN32652461.

Reported outcomes for planned caesarean section versus planned vaginal delivery: A systematic review

BACKGROUND

There is currently no consensus regarding the outcomes and outcome measures that should be reported in studies assessing planned mode of birth.

OBJECTIVE

To develop an inventory for reported outcomes for studies comparing planned caesarean section (CS) and planned vaginal delivery (VD) for women age 18-45.

METHODS

A systematic review of outcomes reported in prospective studies investigating planned CS and planned VD was conducted. Three online databases, Ovid SP version of MEDLINE and EMBASE and the Cochrane Pregnancy and Childbirth Group's Trials Register, were searched from 2011 to June 2019. The inclusion criteria were: prospective studies evaluating planned mode of birth, age 18-45, singleton pregnancy, gestational age 37-40 weeks, >100 participants, middle or high income countries. No language restrictions were applied. Two researchers independently screened titles and abstracts, and subsequently reviewed the full text of each selected study to assess for eligibility. Discrepancies were resolved by discussion with a third author. The selected studies were evaluated using the MOMENT criteria. Outcomes and outcome measures were systematically extracted and organised into an inventory.

RESULTS

63 prospective studies comparing planned CS versus planned VD including data from 6,397,310 women were included. 37 studies (59%) investigating planned CS versus planned VD fulfilled four or more MOMENT criteria. In total, 43 different primary outcomes and 79 different primary outcome measures, and 12 different secondary outcomes and 31 secondary outcome measures were identified from studies investigating planned CS versus planned VD.

CONCLUSION

The findings of this study will contribute to the development of a core outcome set for planned mode of birth in the future. Standardising outcomes will aid comparison and interpretation of data pertaining to planned CS versus planned VD. PROSPERO registration: CRD42019133104.

Towards a European health research and innovation cloud (HRIC)

The European Union (EU) initiative on the Digital Transformation of Health and Care (Digicare) aims to provide the conditions necessary for building a secure, flexible, and decentralized digital health infrastructure. Creating a European Health Research and Innovation Cloud (HRIC) within this environment should enable data sharing and analysis for health research across the EU, in compliance with data protection legislation while preserving the full trust of the participants. Such a HRIC should learn from and build on existing data infrastructures, integrate best practices, and focus on the concrete needs of the community in terms of technologies, governance, management, regulation, and ethics requirements. Here, we describe the vision and expected benefits of digital data sharing in health research activities and present a roadmap that fosters the opportunities while answering the challenges of implementing a HRIC. For this, we put forward five specific recommendations and action points to ensure that a European HRIC: i) is built on established standards and guidelines, providing cloud technologies through an open and decentralized infrastructure; ii) is developed and certified to the highest standards of interoperability and data security that can be trusted by all stakeholders; iii) is supported by a robust ethical and legal framework that is compliant with the EU General Data Protection Regulation (GDPR); iv) establishes a proper environment for the training of new generations of data and medical scientists; and v) stimulates research and innovation in transnational collaborations through public and private initiatives and partnerships funded by the EU through Horizon 2020 and Horizon Europe.

Electrochemical characteristics of ultramicro-dimensioned SIROF electrodes for neural stimulation and recording

OBJECTIVE

With ever increasing applications of neural recording and stimulation, the necessity for developing neural interfaces with higher selectivity and lower invasiveness is inevitable. Reducing the electrode size is one approach to achieving such goals. In this study, we investigated the effect of electrode geometric surface area (GSA), from 20 μm² to 1960 μm², on the electrochemical impedance and charge-injection properties of sputtered iridium oxide (SIROF) coated electrodes in response to current-pulsing typical of neural stimulation. These data were used to assess the electrochemical properties of ultra-small SIROF electrodes (GSA  <  200 μm²) for stimulation and recording applications.

APPROACH

SIROF charge storage capacities (CSC), impedance, and charge-injection characteristics during current-pulsing of planar, circular electrodes were evaluated in an inorganic model of interstitial fluid (model-ISF).

MAIN RESULTS

SIROF electrodes as small as 20 μm² could provide 1.3 nC/phase (200 μs pulse width, 0.6 V versus Ag|AgCl interpulse bias) of charge during current pulsing. The 1 kHz impedance of all electrodes used in this study were below 1 MΩ, which is suitable for neural recording.

SIGNIFICANCE

Ultra-small SIROF electrodes are capable of charge injection in buffered saline at levels above some reported thresholds for neural stimulation with microelectrodes.

Protocol for a Randomised controlled trial to Evaluate the effectiveness and cost benefit of prescribing high dose FLuoride toothpaste in preventing and treating dEntal Caries in high-risk older adulTs (reflect trial)

BACKGROUND

Dental caries in the expanding elderly, predominantly-dentate population is an emerging public health concern. Elderly individuals with heavily restored dentitions represent a clinical challenge and significant financial burden for healthcare systems, especially when their physical and cognitive abilities are in decline. Prescription of higher concentration fluoride toothpaste to prevent caries in older populations is expanding in the UK, significantly increasing costs for the National Health Services (NHS) but the effectiveness and cost benefit of this intervention are uncertain. The Reflect trial will evaluate the effectiveness and cost benefit of General Dental Practitioner (GDP) prescribing of 5000 ppm fluoride toothpaste and usual care compared to usual care alone in individuals 50 years and over with high-risk of caries.

METHODS/DESIGN

A pragmatic, open-label, randomised controlled trial involving adults aged 50 years and above attending NHS dental practices identified by their dentist as having high risk of dental caries. Participants will be randomised to prescription of 5000 ppm fluoride toothpaste (frequency, amount and duration decided by GDP) and usual care only. 1200 participants will be recruited from approximately 60 dental practices in England, Scotland and Northern Ireland and followed up for 3 years. The primary outcome will be the proportion of participants receiving any dental treatment due to caries. Secondary outcomes will include coronal and root caries increments measured by independent, blinded examiners, patient reported quality of life measures, and economic outcomes; NHS and patient perspective costs, willingness to pay, net benefit (analysed over the trial follow-up period and modelled lifetime horizon). A parallel qualitative study will investigate GDPs' practises of and beliefs about prescribing the toothpaste and patients' beliefs and experiences of the toothpaste and perceived impacts on their oral health-related behaviours.

DISCUSSION

The Reflect trial will provide valuable information to patients, policy makers and clinicians on the costs and benefits of an expensive, but evidence-deficient caries prevention intervention delivered to older adults in general dental practice.

TRIAL REGISTRATION

ISRCTN: 2017-002402-13 registered 02/06/2017, first participant recruited 03/05/2018. Ethics Reference No: 17/NE/0329/233335. Funding Body: Health Technology Assessment funding stream of National Institute for Health Research. Funder number: HTA project 16/23/01. Trial Sponsor: Manchester University NHS Foundation Trust, Oxford Road, Manchester, M13 9WL. The Trial was prospectively registered.

The impact of third- or fourth-degree perineal tears on the second pregnancy: A cohort study of 182,445 Scottish women

This study aimed to investigate the reproductive impact of a third- or fourth-degree tear in primigravid women. A retrospective population-based cohort study was conducted using data from Scottish Morbidity Records (SMR02). Primigravid women with a vaginal birth in Scotland from 1997 until 2010 were included. Exposure was third- or fourth-degree tear in the first pregnancy. The second pregnancy rate, interpregnancy interval and third- or fourth-degree tear in a second pregnancy were the primary outcomes. A nested case-control study was used to determine factors associated with repeat third- or fourth-degree tears in a second vaginal birth. Cox regression analysis and logistic regression were used to look for associations. Initial third- or fourth-degree tear occurred in 2.8% women (5174/182445). The percentage of third- or fourth-degree tears in first vaginal births increased from 1% in 1997 to 4.9% in 2010. There was no difference in having a second pregnancy (adjusted Odds Ratio (aOR) 0.98 (99%CI 0.89–1.09)) or the median interpregnancy interval to second pregnancy (adjusted Hazard Ratio (aHR) 1.01 (99%CI 0.95–1.08)) after an initial third- or fourth-degree tear. Women were over four times more likely to have a repeat injury in a subsequent vaginal birth (n = 149/333, aOR 4.68 (99% 3.52–6.23)) and were significantly more likely to have an elective caesarean section in their second pregnancy (n = 887/3333, 26.6%; 12.75 (11.29–14.40)). Increased maternal age and birthweight ≥4500g were risk factors for repeat injury. Third- and fourth-degree tears are increasing in Scotland. Women do not delay or avoid childbirth after initial third- or fourth-degree tear. However, women are more likely to have a repeat third- or fourth-degree tear or an elective caesarean section in the second pregnancy. Strategies to prevent third- or fourth-degree tears are needed.

Cesarean section in China, Taiwan, and Hong Kong-A safe choice for women and clinicians?

Mairead Black and Sohinee Bhattacharya discuss research findings on preferences for cesarean delivery in Asian settings and share their Perspective on facilitating woman-centered birth choices in China following the end of the one-child policy.

Intervention thresholds and cesarean section rates: A time-trends analysis

INTRODUCTION

To improve understanding of rising cesarean section (CS) rates in the UK, this study assessed the relation between clinician thresholds for performing CS for delayed labor progress or suspected fetal distress and corresponding CS rates in Aberdeen, UK.

MATERIAL AND METHODS

Time-trends analysis of term births from 1988 to 2012 in a population of nulliparous women (N = 53 745) in Aberdeen, UK, using Chi-square test for trend, and binary logistic regression. Data were obtained from the Aberdeen Maternity and Neonatal Databank.

RESULTS

Unplanned CS rates per quintile increased from 11.0% (1391/12 686) to 21.1% (2383/11 273) between 1988 and 2012, while planned CS rates increased from 2.7% (338/12 686) to 5.2% (591/11 273). The median duration of labor before CS for delayed progress per quintile decreased from 17.2 (IQR 12.5-22.3) to 13.1 hours (9.6-16.9) before first stage CS and from 17.1 (12.6-22.3) to 15.3 (11.5-19.1) hours before second stage CS (P < .001). The proportion of CS for suspected fetal distress performed with evidence of fetal acidosis declined from 23.4% (98/418) to 17.4% (106/608) per quintile (P < .01). Neonatal unit admission (adjusted OR 1.99, 95% CI 1.85-2.14) was more likely following unplanned CS than vaginal births. Birth trauma was less likely following both unplanned (adjusted OR 0.48, 95% CI 0.39-0.60) and planned (adjusted OR 0.33, 95% CI 0.18-0.63) CS.

CONCLUSION

Increased CS rates can be partly attributed to lowered clinical thresholds for intrapartum CS. Higher CS rates are associated with less birth trauma for the offspring.

Increasing inequality in childhood obesity in primary schools in a northern English town

OBJECTIVE

To undertake an analysis of National Child Measurement Programme (NCMP) data to quantify the obesity prevalence gap over time between children in primary schools in the most and least deprived areas of Doncaster.

STUDY DESIGN

The research design for this study was retrospective quantitative analysis of secondary data.

METHODS

The study undertook secondary analysis of NCMP data on obesity prevalence in children in Reception Year and Year 6 in primary schools in Doncaster for the period 2006-2007 to 2014-2015. Data were combined into three 3-year periods (2006-2007 to 2008-2009; 2009-2010 to 2011-2012; and 2012-2013 to 2014-2015), and schools were grouped by deprivation based on the national Indices of Multiple Deprivation 2015. Analysis was undertaken to assess whether there is a difference in obesity prevalence for Reception Year and Year 6 children in schools in the most deprived areas compared with the least deprived (prevalence gap), over time.

RESULTS

The difference in obesity prevalence between children attending schools in the most and least deprived areas has increased over time. For Reception Year children, the prevalence gap has widened from a difference of 1.01% higher in the most deprived schools in 2006-2007 to 2008-2009 to 3.64% higher in 2012-2013 to 2014-2015. In the same time periods, for Year 6 children, the obesity prevalence gap has also increased over time from 2.82% to 5.08%.

CONCLUSIONS

There is inequality in relation to obesity in primary school children in Doncaster with those in schools in the most deprived areas carrying the greatest burden. Research is needed to understand why the plateau seen nationally is not reaching the most deprived children.