Utilization of a SARS-CoV-2-positive donor for liver transplantation

Liver transplantation rates have been negatively affected by the pandemic caused by coronavirus disease 2019 (COVID-19), the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Current practice in the liver transplant community is to avoid utilizing SARS-CoV-2-positive donors for liver transplantation unless there is a compelling reason such as recipient illness severity. In this case, we report the use of a donor who had a positive exposure to and symptom history for COVID-19 and tested positive for SARS-CoV-2 on admission for a liver transplant recipient with primary sclerosing cholangitis and a Model of End-Stage Liver Disease score of 23 with no known COVID-19 exposures. We focus on the decision to accept this particular organ, as well as the discussion with the recipient about the unknowns of disease transmission and risk associated with this donor. The current case argues that transplant programs should begin to consider low-risk donors with positive SARS-CoV-2 testing for recipients who have the potential to benefit from liver transplantation, which may not only be those with the most severe illness.

Evaluation of antimicrobial activity against Enterococcus faecalis of activated chelating agents in different final rinse protocols: An ex vivo study

Background

To evaluate the antimicrobial activity of the following chelating agents against Enterococcus faecalis using quantitative polymerase chain reaction (qPCR) analysis: 1% peracetic acid (PA), 1% peracetic acid with 0.1% cetrimide (PAC), and 17% ethylenediaminetetraacetic acid (EDTA) activated by passive ultrasonic irrigation (PUI) or with Easy Clean (EC), all followed by 2.5% sodium hypochlorite (NaOCl).

Material and Methods

A total of 80 permanent human mandibular premolars were randomly divided into eight experimental groups according to the chemical solution and agitation protocol used: Group PA + PUI; Group PA + EC; Group PAC + PUI; PAC + EC; group EDTA + PUI; EDTA + EC, all followed by 2.5% NaOCl; and two control groups with saline solution(NaCl): NaCl + PUI and NaCl + EC. Microbial samples were collected before (S1) and after the irrigation protocol (S2). Intracanal E. faecalis reduction analysis was performed by qPCR. Intragroup analysis was performed using the Wilcoxon signed-rank test for paired data, and intergroup analysis was performed using the Wilcoxon Mann-Whitney U test for independent samples. The significance level was set at p< 0.05.

Results

A significant difference was found between S1 and S2 in all groups except NaCl+ EC (p = 0.1602). Comparison between groups showed that PAC + PUI was significantly different from PA +EC (p = 0.0448).

Conclusions

The activated chelating agents were effective against E. faecalis, with significant results compared to the control groups. The peracetic acid with cetrimide activated by PUI showed better results than peracetic acid with EC.

Key words:Easy clean, Final irrigation protocols, Passive ultrasonic irrigation, Peracetic acid.

Cost Analysis of Liver Acquisition Fees Before and After Acuity Circle Policy Implementation

Importance

Acuity circles (AC) liver allocation policy was implemented to eliminate donor service area geographic boundaries from liver allocation and to decrease variability in median Model of End-stage Liver Disease (MELD) score at transplant and wait list mortality. However, the broader sharing of organs was also associated with more flights for organ procurements and higher costs associated with the increase in flights.

Objective

To determine whether the costs associated with liver acquisition changed after the implementation of AC allocation.

Design, Setting, and Participants

This single-center cost comparison study analyzed fees associated with organ acquisition before and after AC allocation implementation. The cost data were collected from a single transplant institute with 2 liver transplant centers, located 30 miles apart, in different donation service areas. Cost, recipient, and transportation data for all cases that included fees associated with liver acquisition from July 1, 2019, to October 31, 2020, were collected.

Exposures

Primary liver offer acceptance with associated organ procurement organization or charter flight fees.

Main Outcomes and Measures

Specific fees (organ acquisition, surgeon, import, and charter flight fees) and total fees per donor were collected for all accepted liver donors with at least 1 associated fee during the study period.

Results

Of 213 included donors, 171 were used for transplant; 90 of 171 (52.6%) were male, and the median (interquartile range) age of donors was 41.0 (30.0-52.8) years in the pre-AC period and 36.9 (24.0-48.8) years in the post-AC period. There was no significant difference in the post-AC compared with pre-AC period in median (range) MELD score (24 [8-40] vs 25 [6-40]; P = .27) or median (range) match run sequence (15 [1-3951] vs 10 [1-1138]; P = .31), nor in mean (SD) distance traveled (155.83 [157.00] vs 140.54 [144.33] nautical miles; P = .32) or percentage of donors requiring flights (58.5% [69 of 118] vs 56.8% [54 of 95]; P = .82). However, costs increased significantly in the post-AC period: total cost increased 16% per accepted donor (mean [SD] of $52 966 [13 278] vs $45 725 [9300]; P < .001) and 55% per declined donor (mean [SD] of $15 865 [3942] vs $10 217 [4853]; P < .001). Contributing factors included more than 2-fold increases in the proportions of donors incurring import fees (31.4% [37 of 118] vs 12.6% [12 of 95]; P = .002) and surgeon fees (19.5% [23 of 118] vs 9.5% [9 of 95]; P = .05), increased acquisition fees (10% increase; mean [SD] of $43 860 [3266] vs $39 980 [2236]; P < .001), and increased flight expenses (43% increase; mean [SD] of $12 904 [6066] vs $9049 [5140]; P = .002).

Conclusions and Relevance

The unintended consequences of implementing broader sharing without addressing organ acquisition fees to account for increased importation between organ procurement organizations must be remedied to contain costs and ensure viability of transplant programs.

Association of COVID-19 With Achieving Time-to-Surgery Benchmarks in Patients With Musculoskeletal Trauma

Question

Were resource constraints due to the COVID-19 pandemic associated with a delay in urgent fracture surgery beyond national time-to-surgery benchmarks?

Findings

In this cohort pre-post study that included 3589 patients, there was no association between time to surgery and COVID-19 in either open fracture or closed femur/hip fracture cohorts.

Meaning

Despite concerns that the unprecedented challenges associated with the COVID-19 pandemic would delay acute management of urgent surgery, many hospital systems within the US were able to implement strategies in keeping with time-to-surgery standards for orthopedic trauma.

Importance

In response to the COVID-19 pandemic, many hospital systems were forced to reduce operating room capacity and reallocate resources. The outcomes of these policies on the care of injured patients and the maintenance of emergency services have not been adequately reported.

Objective

To evaluate whether the COVID-19 pandemic was associated with delays in urgent fracture surgery beyond national time-to-surgery benchmarks.

Design, Setting, and Participants

This retrospective cohort study used data collected in the Program of Randomized Trials to Evaluate Preoperative Antiseptic Skin Solutions in Orthopaedic Trauma among at 20 sites throughout the US and Canada and included patients who sustained open fractures or closed femur or hip fractures.

Exposure

COVID-19–era operating room restrictions were compared with pre–COVID-19 data.

Main Outcomes and Measures

Surgery within 24 hours after injury.

Results

A total of 3589 patients (mean [SD] age, 55 [25.4] years; 1913 [53.3%] male) were included in this study, 2175 pre–COVID-19 and 1414 during COVID-19. A total of 54 patients (3.1%) in the open fracture cohort and 407 patients (21.8%) in the closed hip/femur fracture cohort did not meet 24-hour time-to-surgery benchmarks. We were unable to detect any association between time to operating room and COVID-19 era in either open fracture (odds ratio [OR], 1.40; 95% CI, 0.77-2.55; P = .28) or closed femur/hip fracture (OR, 1.01; 95% CI, 0.74-1.37; P = .97) cohorts. In the closed femur/hip fracture cohort, there was no association between time to operating room and regional COVID-19 prevalence (OR, 1.07; 95% CI, 0.70-1.64; P = .76).

Conclusions and Relevance

In this cohort study, there was no association between meeting time-to-surgery benchmarks in either open fracture or closed femur/hip fracture during the COVID-19 pandemic compared with before the pandemic. This is counter to concerns that the unprecedented challenges associated with managing the COVID-19 pandemic would be associated with clinically significant delays in acute management of urgent surgical cases and suggests that many hospital systems within the US were able to effectively implement policies consistent with time-to-surgery standards for orthopedic trauma in the context of COVID-19–related resource constraints.

Development of a solute and defect concentration dependant Ising model for the study of transmutation induced segregation in neutron irradiated W-(Re, Os) systems

In this study, radiation-induced precipitation of transmutation products is addressed via the development of a new solute and vacancy concentration dependant Ising model for the W-Re-Os system. This new model includes interactions between both Os and Re atoms with vacancies, thus facilitating more representative simulations of transmutation in fusion reactor components. Local solute concentration dependencies are introduced for the W-Re, W-Os and Re-Os pair interactions. The model correctly accounts for the repulsion between small clusters of vacancies and the attraction between larger clusters/voids, via the introduction of local vacancy concentration dependant interaction coefficients between pairs of atoms and vacancies. To parameterise the pair interactions between atoms and/or vacancies, the enthalpy of mixing, ΔH_mix, for various configurations and solute/defect concentrations, was calculated using density functional theory, within 6 binary systems: W-Re, W-Os, Re-Os, W-vacancy, Re-vacancy and Os-vacancy. The new energy model was implemented into the SPPARKS Monte Carlo code, and successfully used to predict the formation of voids decorated with Re and Os solute atoms. Analysis suggests that there is a strong thermodynamic tendency for Os to bind to these voids with a comparatively weaker binding from Re atoms. The binding energies of various solute/vacancy clusters were calculated and showed that Re and Os solute atoms tend to stabilise small clusters of vacancies, increasing the attractive binding energy between the constituents.

Continuity in ovine Johne's disease vaccination practices despite a decline in clinical disease

The Gudair® vaccine has been commercially available in Australia for almost two decades for the control of ovine Johne's disease, but concerns have been raised about potential discontinuation of vaccination by producers after a decline in the incidence of clinical disease. An online questionnaire was distributed to Australian sheep producers to identify the proportion of respondents discontinuing the Gudair vaccine and reasons for discontinuation. Results revealed that 88% of sheep producers surveyed have continued to vaccinate their sheep with Gudair, with continuation greater for predominantly Merino sheep flocks. Reasons for discontinuing vaccination stemmed from management, economic or health concerns. These results suggest that Gudair is still widely used by Australian sheep producers and concerns about large-scale discontinuation are unfounded. These findings have implications for ovine Johne's disease control programs in Australia.

Futility risk model for predicting outcome after cardiac resynchronization therapy defibrillator implantation: data from a nationwide analysis

Funding Acknowledgements

Type of funding sources: None.

Objective. Risk-benefit assessment for cardiac resynchronization therapy defibrillator (CRT-D) over a CRT pacemaker (CRT-P) is still a matter of debate. We aimed to identify patients with a bad outcome within one year after CRT-D implantation, and to develop a Futile CRT-D score.

Methods. Based on the administrative hospital-discharge database, all consecutive patients treated with CRT-D implantation in France between 2010 and 2019 were included. A prediction model was derived and validated for one-year all-cause death after CRT-D implantation (considered as futility) by using split-sample validation.

Results. 28,503 patients were included in the analysis (mean age 68 ± 10 years); 2,139 (7.5%) deaths were recorded in the first year. In the derivation cohort (n = 14,252), the final logistic regression model included as main predictors of futility older age, diabetes, mitral regurgitation, history of hospital stay with heart failure, history of pulmonary oedema, atrial fibrillation, renal, pulmonary, liver, or thyroid disease, denutrition and anemia. Based on Futile CRT-D score, 17% of these patients were categorized at high risk (Futile CRT-D score ≥13) and predicted futility at 17%.

Conclusion.  The futility CRT-D score, established from a large nationwide cohort of patients treated with CRT-D may provide a relevant tool for optimizing healthcare decision. Death at one year in patients with CRTD OR (95%CI)pPointsAge (quartile)1.353 (1.266-1.446)&lt;0.00012Diabetes mellitus1.413 (1.225-1.629)&lt;0.00012Heart failure with congestion1.908 (1.501-2.423)&lt;0.00013History of pulmonary edema1.445 (1.194-1.749)&lt;0.00012Mitral regurgitation1.259 (1.074-1.475)0.0042Atrial fibrillation1.601 (1.395-1.838)&lt;0.00012Left BBB0.803 (0.698-0.924)0.002-1Dyslipidemia0.809 (0.696-0.940)0.006-1Denutrition1.709 (1.360-2.147)&lt;0.00012Chronic kidney disease1.574 (1.321-1.875)&lt;0.00012Lung disease1.230 (1.052-1.437)0.0092Sleep apnea syndrome0.740 (0.596-0.919)0.007-1Liver disease1.747 (1.384-2.206)&lt;0.00012Anaemia1.325 (1.105-1.589)0.0022BBB = bundle branch block.; * age quartile: 1 point when age &gt;61, 2 points when age &gt;69, 3 points when age &gt;75.Abstract Figure. AUC and incidences of all-causes death

Selective screening imaging of the aortoiliac arterial system in kidney transplant candidates with non-contrast pelvic computed tomography

Non-contrast pelvic computed tomography (CT) can detect severe iliac artery calcifications that present technical contraindications to kidney transplantation (TCT). We screened 454 asymptomatic patients with a history of any of the following: hemodialysis >10 years, diabetes mellitus >20 years, coronary artery disease (CAD) with percutaneous or surgical interventions, carotid disease, diabetes with below-/above-knee amputations, and heart-kidney transplantation candidacy. Patients with normal dorsalis pedis and/or tibialis posterior pulses were not screened. A total of 8.4% had severe calcifications with TCT; CT determined laterality for implantation in 13.9%. No patients with the following characteristics were classified as TCT: age <40 years, hemodialysis >10 years, carotid arterial disease, prior lower extremity amputation, or heart-kidney transplantation candidacy. CAD was associated with TCT in univariate though not multivariate analysis. Limiting screening to patients >40 years, with DM >20 years, or with CAD, 9.8% had a TCT and CT determined transplant laterality in 14.2%. Screening for severe iliac artery calcifications is useful for selected kidney transplantation candidates over age 40. It can assist with laterality choice or surgeon determination of TCT. Cost and radiation exposure risks should be weighed against the morbidity risks from unnecessary surgery.

Challenges in quantification of photocatalytic NO2 abatement effectiveness under real world exposure conditions illustrated by a case study

Health risks due to NO₂ exposure commonly exceed acceptable levels in modern societies. Among the measures to reduce such risks, photocatalytic materials present a promising technology. However, while the pollutant remediation of such materials has been extensively validated in laboratory studies, the performance under real world environmental exposure conditions is still subject to controversy. Indeed, a comparison of available in-situ monitoring studies manifests non-conclusive and highly scattered results regarding the photocatalytic effectiveness observed. The reasons for this behaviour must be carefully explored in order to prevent non-efficient photocatalytic applications from being put into practice on a larger scale. This paper presents a comprehensive large-scale study for assessing the photocatalytic NO₂ remediation by active pavements in a street of Madrid (Spain), comprising different in-situ monitoring techniques. The discussion is enriched by relating the obtained results to those of other large-scale studies. The discrepancies between these results may be traced back to different circumstances, among them the distance between the active pavement and the pollutant concentration sampling inlet, as well as to significant site-specific and time-dependent variations of pollutant concentrations and climatic parameters. Under due consideration of these influences, for materials with relatively high initial effectiveness, it was concluded that in most such applications, the average NO₂ removal effectiveness, if evaluated at a typical inlet height of Air Quality Stations (3 m), will not exceed a value of 4% (averaged over a sufficiently large number of measurement points in the area of application and a sustained amount of time, i.e. several months). When considering more realistic human exposure conditions (lower heights and daytime), it might be justified to assume somewhat higher average effectiveness.

Effect of subcutaneous tissue depth on outcomes of kidney transplantation

Although post-kidney transplant (KT) wound complications are associated with elevated body mass index (BMI), BMI is not an accurate surrogate of obesity. On the other hand, subcutaneous depth (SQD) measurement is a direct marker of truncal obesity. We examined outcomes of differing intraoperative SQD measurements in 113 KT-only recipients over 20 months. Recipients' median age was 51 years; median BMI, 28 kg/m²; and mean SQD, 2.9 cm. Patients were stratified into groups of SQD ≤2.5 cm, >2.5-5 cm, and >5 cm. An SQD of >2.5 to 5 cm correlated with a BMI of 30 kg/m² (obesity) and an SQD >5 cm correlated with a BMI >35 kg/m² (severe obesity). Degree of SQD was not associated with more frequent technical complications such as fascial dehiscence, lymphocele formation, renal artery thrombosis/stenosis, urine leak, or ureteral stenosis. However, an SQD >2.5 cm was a risk factor for requiring a wound vacuum-assisted closure device. There was no difference in graft or patient survival among the three SQD groups. Obesity, as measured directly by SQD, was not associated with increased technical complications or poor outcomes after KT. As expected, there was a higher incidence of wound complications in the higher SQD groups requiring intervention.

Factors Associated with Nonsuppression of HIV Infection in the Spanish VACH Cohort

We aim to determine the prevalence of HIV nonsuppression and factors associated with it. This is a cross-sectional multicenter study carried out in January 2016 with data of the VACH Cohort, a registry participated by 23 hospitals from most regions of Spain. The prevalence of HIV nonsuppression, defined as HIV RNA ≥200 copies/mL, is documented. The possible association of HIV nonsuppression with sociodemographic and clinical variables is assessed with a logistic regression analysis. A total of 30,843 adult patients are included; 7,358 of them (23.86%) have nonsuppressed HIV. An association is found between nonsuppression of HIV and the following variables: lower body mass index, lower age of patients in their last registered visit, lower number of visits carried out during follow-up, lower last available CD4 cell count, higher age of patients at the time of their HIV infection diagnosis, higher lowest available CD4 cell count, higher highest available HIV RNA, enrolment in the Cohort in first years of the HIV epidemic, region of Spain where the patient is attended other than Andalusia, HIV risk factor other than sexual, occurrence of death during follow-up, hepatitis C coinfection, being a smoker, pertaining to groups A1 or A2 of the CDC groups classification, and not taking antiretroviral treatment, p < .001 in all cases. HIV nonsuppression is still common with the effective antiretroviral treatment nowadays available. HIV nonsuppression is associated with HIV risk factor other than sexual, hepatitis C coinfection, and being a smoker, among other factors.

Gene expression and functional deficits underlie TREM2-knockout microglia responses in human models of Alzheimer's disease

The discovery of TREM2 as a myeloid-specific Alzheimer's disease (AD) risk gene has accelerated research into the role of microglia in AD. While TREM2 mouse models have provided critical insight, the normal and disease-associated functions of TREM2 in human microglia remain unclear. To examine this question, we profile microglia differentiated from isogenic, CRISPR-modified TREM2-knockout induced pluripotent stem cell (iPSC) lines. By combining transcriptomic and functional analyses with a chimeric AD mouse model, we find that TREM2 deletion reduces microglial survival, impairs phagocytosis of key substrates including APOE, and inhibits SDF-1α/CXCR4-mediated chemotaxis, culminating in an impaired response to beta-amyloid plaques in vivo. Single-cell sequencing of xenotransplanted human microglia further highlights a loss of disease-associated microglial (DAM) responses in human TREM2 knockout microglia that we validate by flow cytometry and immunohistochemistry. Taken together, these studies reveal both conserved and novel aspects of human TREM2 biology that likely play critical roles in the development and progression of AD.

Outcomes by sex following treatment initiation with darunavir/cobicistat in a large Spanish cohort of the CODAR study (GeSIDA 9316)

BACKGROUND

Few women have been included in darunavir/cobicistat clinical development studies, and hardly any of them were antiretroviral experienced or treated with anything other than triple-based therapies.

OBJECTIVES

Our aim was to increase our knowledge about women living with HIV undergoing darunavir/cobicistat-based regimens.

METHODS

A multicentre (21 hospitals), retrospective study including a centrally selected random sample of HIV-1 patients starting a darunavir/cobicistat-based regimen from June 2014 to March 2017 was planned. Baseline characteristics, 24 and 48 week viral load response (<50 copies/mL), CD4+ lymphocyte count increase, time to change darunavir/cobicistat and adverse event occurrence were all compared by sex. The study was approved by each of the 21 ethics committees, and patients signed informed consent.

RESULTS

Out of 761 participants, 193 were women. Similar characteristics were found for both sexes, except that the women had a longer duration of HIV infection (P = 0.001), and were less frequently pre-treated with darunavir/cobicistat in their previous regimen (P = 0.02). The main reason for using a darunavir/cobicistat-based regimen was simplification, without differences by sex, while monotherapy seems to be more frequently prescribed in women than in men (P = 0.067). The main outcomes, HIV viral load response, CD4+ lymphocyte count increase at 24 or 48 weeks, occurrence of adverse events, main reasons for changing and time to the modify darunavir/cobicistat regimen, did not show differences between the sexes.

CONCLUSIONS

No sex disparities were found in the main study outcomes. These results support the use of a darunavir/cobicistat-based regimen in long-term pre-treated women. Clinical Trial.gov No. NCT03042390.