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Infections remain a major threat to successful kidney transplantation (KT). To characterize the landscape and impact of post‐KT infections in the modern era, we used United States Renal Data System (USRDS) data linked to the Scientific Registry of Transplant Recipients (SRTR) to study 141 661 Medicare‐primary kidney transplant recipients from January 1, 1999 to December 31, 2014. Infection diagnoses were ascertained by International Classification of Diseases, Ninth Revision (ICD‐9) codes. The cumulative incidence of a post‐KT infection was 36.9% at 3 months, 53.7% at 1 year, and 78.0% at 5 years. The most common infections were urinary tract infection (UTI; 46.8%) and pneumonia (28.2%). Five‐year mortality for kidney transplant recipients who developed an infection was 24.9% vs 7.9% for those who did not, and 5‐year death‐censored graft failure (DCGF) was 20.6% vs 10.1% (P <.001). This translated to a 2.22‐fold higher mortality risk (adjusted hazard ratio [aHR]: 2.152.222.29, P <.001) and 1.92‐fold higher DCGF risk (aHR: 1.841.911.98, P <.001) for kidney transplant recipients who developed an infection, although the magnitude of this higher risk varied across infection types (for example, 3.11‐fold higher mortality risk for sepsis vs 1.62‐fold for a UTI). Post‐KT infections are common and substantially impact mortality and DCGF, even in the modern era. Kidney transplant recipients at high risk for infections might benefit from enhanced surveillance or follow‐up to mitigate these risks. This national study of kidney transplant recipients shows that infections are common, are associated with approximately twofold increased risk of both mortality and death‐censored graft failure, and thus are still an important driver of posttransplant outcomes. [ABSTRACT FROM AUTHOR]

KIDNEY transplants, ORGAN donors, PEDIATRICS, KIDNEY failure, TRANSPLANTATION of organs, tissues, etc., STATISTICAL significance, DESCRIPTIVE statistics, and COVID-19 pandemic

Background: In March 2020, COVID-19 infections began to rise exponentially in the USA, placing substantial burden on the healthcare system. As a result, there was a rapid change in transplant practices and policies, with cessation of most procedures. Our goal was to understand changes to pediatric kidney transplantation (KT) at the national level during the COVID-19 epidemic. Methods: Using SRTR data, we examined changes in pediatric waitlist registration, waitlist removal or inactivation, and deceased donor and living donor (DDKT/LDKT) events during the start of the disease transmission in the USA compared with the same time the previous year. Results: We saw an initial decrease in DDKT and LDKT by 47% and 82% compared with expected events and then a continual increase, with numbers reaching expected prepandemic levels by May 2020. In the early phase of the pandemic, waitlist inactivation and removals due to death or deteriorating condition rose above expected values by 152% and 189%, respectively. There was a statistically significant decrease in new waitlist additions (IRR 0.49 0.65 0.85) and LDKT (IRR 0.17 0.38 0.84) in states with high vs. low COVID activity. Transplant recipients during the pandemic were more likely to have received a DDKT, but had similar calculated panel–reactive antibody (cPRA) values, waitlist time, and cause of kidney failure as before the pandemic. Conclusions: The COVID-19 pandemic initially reduced access to kidney transplantation among pediatric patients in the USA but has not had a sustained effect. [ABSTRACT FROM AUTHOR]

COVID-19, TRANSPLANTATION of organs, tissues, etc., SARS-CoV-2, CRITICALLY ill, and KIDNEYS

In our first survey of transplant centers in March 2020, >75% of kidney and liver programs were either suspended or operating under restrictions. To safely resume transplantation, we must understand the evolving impact of COVID‐19 on transplant recipients and center‐level practices. We therefore conducted a six‐week follow‐up survey May 7‐15, 2020, and linked responses to the COVID‐19 incidence map, with a response rate of 84%. Suspension of live donor transplantation decreased from 72% in March to 30% in May for kidneys and from 68% to 52% for livers. Restrictions/suspension of deceased donor transplantation decreased from 84% to 58% for kidneys and from 73% to 42% for livers. Resuming transplantation at normal capacity was envisioned by 83% of programs by August 2020. Exclusively using local recovery teams for deceased donor procurement was reported by 28%. Respondents reported caring for a total of 1166 COVID‐19–positive transplant recipients; 25% were critically ill. Telemedicine challenges were reported by 81%. There was a lack of consensus regarding management of potential living donors or candidates with SARS‐CoV‐2. Our findings demonstrate persistent heterogeneity in center‐level response to COVID‐19 even as transplant activity resumes, making ongoing national data collection and real‐time analysis critical to inform best practices. [ABSTRACT FROM AUTHOR]

KIDNEY transplants, COVID-19, COVID-19 pandemic, CORONAVIRUS diseases, and EXPECTED returns

In March 2020, coronavirus disease 2019 (COVID‐19) spread rapidly nationally, causing widespread emergent changes to the health system. Our goal was to understand the impact of the epidemic on kidney transplantation (KT), at both the national and center levels, accounting statistically for waitlist composition. Using Scientific Registry of Transplant Recipients data, we compared data on observed waitlist registrations, waitlist mortality, and living‐donor and deceased‐donor kidney transplants (LDKT/DDKT) March 15‐April 30, 2020 to expected events calculated from preepidemic data January 2016‐February 2020. There were few changes before March 15, at which point the number of new listings/DDKT/LDKT dropped to 18%/24%/87% below the expected value (all P <.001). Only 12 centers performed LDKT March 15‐31; by April 30, 40 centers had resumed LDKT. The decline in new listings and DDKT was greater among states with higher per capita confirmed COVID‐19 cases. The number of waitlist deaths was 2.2‐fold higher than expected in the 5 states with highest COVID‐19 burden (P <.001). DCD DDKT and regional/national imports declined nationwide but most steeply in states with the highest COVID‐19 burden. The COVID‐19 epidemic has resulted in substantial changes to KT; we must adapt and learn rapidly to continue to provide safe access to transplantation and limit the growing indirect toll of an already deadly disease. The authors present national‐ and center‐level data on reduced kidney transplant activity early in the COVID‐19 pandemic and link findings to state‐level COVID‐19 burden. [ABSTRACT FROM AUTHOR]

COVID-19 pandemic, KIDNEY transplants, COVID-19, MACHINE learning, and PANDEMICS

Clinical decision‐making in kidney transplant (KT) during the coronavirus disease 2019 (COVID‐19) pandemic is understandably a conundrum: both candidates and recipients may face increased acquisition risks and case fatality rates (CFRs). Given our poor understanding of these risks, many centers have paused or reduced KT activity, yet data to inform such decisions are lacking. To quantify the benefit/harm of KT in this context, we conducted a simulation study of immediate‐KT vs delay‐until‐after‐pandemic for different patient phenotypes under a variety of potential COVID‐19 scenarios. A calculator was implemented (http://www.transplantmodels.com/covid%5fsim), and machine learning approaches were used to evaluate the important aspects of our modeling. Characteristics of the pandemic (acquisition risk, CFR) and length of delay (length of pandemic, waitlist priority when modeling deceased donor KT) had greatest influence on benefit/harm. In most scenarios of COVID‐19 dynamics and patient characteristics, immediate KT provided survival benefit; KT only began showing evidence of harm in scenarios where CFRs were substantially higher for KT recipients (eg, ≥50% fatality) than for waitlist registrants. Our simulations suggest that KT could be beneficial in many centers if local resources allow, and our calculator can help identify patients who would benefit most. Furthermore, as the pandemic evolves, our calculator can update these predictions. This simulation study and interactive online tool model the survival benefit or harm of kidney transplantation in the context of COVID‐19, based on epidemic parameters and individual patient characteristics. McElroy et al comment on page 2971. [ABSTRACT FROM AUTHOR]

ON-site evaluation, STREAMING video, VIDEO excerpts, and MEDICAL technology

Introduction: Telecytology using real‐time microscopy has gained popularity for rapid on‐site evaluations (ROSE). Although proficiency testing is routinely used in cytopathology, no established means of competency assessment is currently available for telecytology. Our aim was to determine the feasibility of a dynamic (real‐time) platform to assess telecytology competency. Methods: Remote Medical Technology dynamic (real‐time) video streaming platform for ROSE is used at our institution, and short video clips of telecytology cases were recorded using Camtasia Studio 8 software during different ROSE sessions. Selected MP4 videos (range 13‐88 seconds, mean 33 seconds), along with clinical histories, were used to build a multiple‐choice question test with one training case and 20 test cases, utilising Tutor (Philips) software to host the web‐based test. The test was voluntary for cytopathologists and cytotechnologists. Answers and feedback from test takers were analysed. Results: Thirteen participants—four cytopathologists and nine cytotechnologists—previously trained to use telecytology, volunteered to take the test. Individual scores ranged from 10 (50%) to 19 (95%) with a median of 16 (80%). Most feedback received involved technical difficulties. Conclusions: We present, to the best of our knowledge, the first tool to assess telecytology competency for ROSE using pre‐recorded dynamic streaming videos. Despite technical challenges related to incorporating videos into a web‐based test, the test was feasible and provided users with valuable feedback about their ROSE performance. Future effort will be devoted to establishing a more user‐friendly test platform and establishing a benchmark for passing scores. This paper illustrates that an assessment tool for telecytology competency for ROSE using pre‐recorded dynamic streaming videos is feasible. In addition, the novel test provided users with valuable feedback about their ROSE performance and provides feedback on the challenges related to telecytology ROSE. [ABSTRACT FROM AUTHOR]

SCHOOL children, DYSLEXIC children, EMERGENT literacy, PHONOLOGICAL awareness, NOISE, and ARTIFICIAL satellite tracking

Humans' propensity to acquire literacy relates to several factors, including the ability to understand speech in noise (SiN). Still, the nature of the relation between reading and SiN perception abilities remains poorly understood. Here, we dissect the interplay between (1) reading abilities, (2) classical behavioral predictors of reading (phonological awareness, phonological memory, and rapid automatized naming), and (3) electrophysiological markers of SiN perception in 99 elementary school children (26 with dyslexia). We demonstrate that, in typical readers, cortical representation of the phrasal content of SiN relates to the degree of development of the lexical (but not sublexical) reading strategy. In contrast, classical behavioral predictors of reading abilities and the ability to benefit from visual speech to represent the syllabic content of SiN account for global reading performance (i.e., speed and accuracy of lexical and sublexical reading). In individuals with dyslexia, we found preserved integration of visual speech information to optimize processing of syntactic information but not to sustain acoustic/phonemic processing. Finally, within children with dyslexia, measures of cortical representation of the phrasal content of SiN were negatively related to reading speed and positively related to the compromise between reading precision and reading speed, potentially owing to compensatory attentional mechanisms. These results clarify the nature of the relation between SiN perception and reading abilities in typical child readers and children with dyslexia and identify novel electrophysiological markers of emergent literacy. Humans' propensity to acquire literacy relates to several factors, one of which is the ability to understand speech in noise. This neuroimaging study reveals that reading abilities and neuronal traces of speech processing in noise are related in multiple specific ways. [ABSTRACT FROM AUTHOR]

PREMATURE labor, BIRTH weight, LOW birth weight, BIRTH intervals, COHORT analysis, CHORIOAMNIONITIS, and CHILDBIRTH at home

Background: Approximately 20.5 million infants were born weighing <2500 g (defined as low birthweight or LBW) in 2015, primarily in low- and middle-income countries (LMICs). Infants born LBW, including those born preterm (<37 weeks gestation), are at increased risk for numerous consequences, including neonatal mortality and morbidity as well as suboptimal health and nutritional status later in life. The objective of this study was to identify predictors of LBW and preterm birth among infants in rural Uganda. Methods: Data were derived from a prospective birth cohort study conducted from 2014–2016 in 12 districts across northern and southwestern Uganda. Birth weights were measured in triplicate to the nearest 0.1 kg by trained enumerators within 72 hours of delivery. Gestational age was calculated from the first day of last menstrual period (LMP). Associations between household, maternal, and infant characteristics and birth outcomes (LBW and preterm birth) were assessed using bivariate and multivariable logistic regression with stepwise, backward selection analyses. Results: Among infants in the study, 4.3% were born LBW (143/3,337), and 19.4% were born preterm (744/3,841). In multivariable analysis, mothers who were taller (>150 cm) (adjusted Odds Ratio (aOR) = 0.42 (95% CI = 0.24, 0.72)), multigravida (aOR = 0.62 (95% CI = 0.39, 0.97)), or with adequate birth spacing (>24 months) (aOR = 0.60 (95% CI = 0.39, 0.92)) had lower odds of delivering a LBW infant Mothers with severe household food insecurity (aOR = 1.84 (95% CI = 1.22, 2.79)) or who tested positive for malaria during pregnancy (aOR = 2.06 (95% CI = 1.10, 3.85)) had higher odds of delivering a LBW infant. In addition, in multivariable analysis, mothers who resided in the Southwest (aOR = 0.64 (95% CI = 0.54, 0.76)), were ≥20 years old (aOR = 0.76 (95% CI = 0.61, 0.94)), with adequate birth spacing (aOR = 0.76 (95% CI = 0.63, 0.93)), or attended ≥4 antenatal care (ANC) visits (aOR = 0.56 (95% CI = 0.47, 0.67)) had lower odds of delivering a preterm infant; mothers who were neither married nor cohabitating (aOR = 1.42 (95% CI = 1.00, 2.00)) or delivered at home (aOR = 1.25 (95% CI = 1.04, 1.51)) had higher odds. Conclusions: In rural Uganda, severe household food insecurity, adolescent pregnancy, inadequate birth spacing, malaria infection, suboptimal ANC attendance, and home delivery represent modifiable risk factors associated with higher rates of LBW and/or preterm birth. Future studies on interventions to address these risk factors may be warranted. [ABSTRACT FROM AUTHOR]

COVID-19, COVID-19 pandemic, KIDNEY transplants, TRANSPLANTATION of organs, tissues, etc., and INVESTIGATIONAL therapies

COVID‐19 is a novel, rapidly changing pandemic: consequently, evidence‐based recommendations in solid organ transplantation (SOT) remain challenging and unclear. To understand the impact on transplant activity across the United States, and center‐level variation in testing, clinical practice, and policies, we conducted a national survey between March 24, 2020 and March 31, 2020 and linked responses to the COVID‐19 incidence map. Response rate was a very high 79.3%, reflecting a strong national priority to better understand COVID‐19. Complete suspension of live donor kidney transplantation was reported by 71.8% and live donor liver by 67.7%. While complete suspension of deceased donor transplantation was less frequent, some restrictions to deceased donor kidney transplantation were reported by 84.0% and deceased donor liver by 73.3%; more stringent restrictions were associated with higher regional incidence of COVID‐19. Shortage of COVID‐19 tests was reported by 42.5%. Respondents reported a total of 148 COVID‐19 recipients from <1 to >10 years posttransplant: 69.6% were kidney recipients, and 25.0% were critically ill. Hydroxychloroquine (HCQ) was used by 78.1% of respondents; azithromycin by 46.9%; tocilizumab by 31.3%, and remdesivir by 25.0%. There is wide heterogeneity in center‐level response across the United States; ongoing national data collection, expert discussion, and clinical studies are critical to informing evidence‐based practices. In this national survey of transplant centers during the COVID‐19 pandemic, the authors report substantial reduction in transplant activity, wide variation in COVID‐19 testing practices, and use of off‐label or investigational therapies in the treatment of 148 COVID‐19‐SOT recipients. [ABSTRACT FROM AUTHOR]

CLOSTRIDIUM difficile, GLUTAMATE dehydrogenase, TREATMENT duration, and ENZYME-linked immunosorbent assay

A proportion of patients suspected of Clostridium difficile infection are unnecessarily placed in contact isolation. By introducing a random-access glutamate dehydrogenase (GDH) test for C. difficile, we aimed to reduce isolation time. In addition, we investigated whether the result of the toxin A&B enzyme immunoassay (EIA) was associated with the decision to initiate antibiotic treatment against C. difficile. This retrospective pre- and post-implementation study was from June 3, 2016, to June 4, 2018. Pre-implementation, only a NAAT was performed. In the post-implementation period, a GDH test was performed; if positive, a toxin A&B EIA followed the same day and subsequently a NAAT. Contact isolation for CDI was discontinued when the GDH test was negative. Median time in isolation was 50.8 h pre-implementation (n = 189) versus 28.0 h post-implementation (n = 119), p < 0.001. The GDH test had a negative predictive value of 98.8% (95% CI 97.9–99.4). In 7/31 (22.6%) patients with a positive NAAT and GDH test and a negative toxin A&B EIA, no antibiotics against C. difficile were initiated versus 4/28 (14.3%) patients who were NAAT, GDH and toxin A&B EIA positive. Introducing a random-access screening test resulted in a significant decrease in patient isolation time. The GDH test had a high negative predictive value making it suitable to determine whether contact isolation can be discontinued. Furthermore, the result of a toxin A&B EIA had limited added value on the percentage of patients in whom antibiotic treatment against C. difficile was initiated. [ABSTRACT FROM AUTHOR]

LUNGS, LONGITUDINAL method, HISTORY, and LUNG transplants

Summary: The aim of this study was to investigate whether there is an impact of donation rates on the quality of lungs used for transplantation and whether donor lung quality affects post‐transplant outcome in the current Lung Allocation Score era. All consecutive adult LTx performed in Eurotransplant (ET) between January 2012 and December 2016 were included (N = 3053). Donors used for LTx in countries with high donation rate were younger (42% vs. 33% ≤45 years, P < 0.0001), were less often smokers (35% vs. 46%, P < 0.0001), had more often clear chest X‐rays (82% vs. 72%, P < 0.0001), had better donor oxygenation ratios (20% vs. 26% with PaO2/FiO2 ≤ 300 mmHg, P < 0.0001), and had better lung donor score values (LDS; 28% vs. 17% with LDS = 6, P < 0.0001) compared with donors used for LTx in countries with low donation rate. Survival rates for the groups LDS = 6 and ≥7 at 5 years were 69.7% and 60.9% (P = 0.007). Lung donor quality significantly impacts on long‐term patient survival. Countries with a low donation rate are more oriented to using donor lungs with a lesser quality compared to countries with a high donation rate. Instead of further stretching donor eligibility criteria, the full potential of the donor pool should be realized. [ABSTRACT FROM AUTHOR]

DISABILITIES, ADOPTED children, PARENTS, INTERNATIONAL adoption, TEACHERS, and SCHOOL plays

Internationally adopted youth (IAY) with disabilities have distinctive needs for adaptive development, and schools play a central role in supporting and meeting these needs. Yet in our qualitative examination of 41 families of IAY with disabilities, we found that these needs are not often well understood by practicing educators and school staff. Using Bronfenbrenner's (2005) bioecological systems model as a framework, we explored the resources utilized by families of IAY with disabilities, including those offered by schools, as well as participants' perceptions of their experiences in utilizing these resources. We found that participants encountered widespread misconceptions regarding adoption, trauma, and disability among school staff and often struggled to access resources necessary for adaptive development. At the same time, teachers and other school staff were often key sources of social and emotional support for IAY with disabilities, and schools were, in general, the central hub of a well-functioning mesosystem. [ABSTRACT FROM AUTHOR]

TOXOPLASMA, POLYMERS, TUBULINS, MICROTUBULES, XENOPUS, and RELATIVES

Background: TgDCX is a doublecortin-domain protein associated with the conoid fibers, a set of strongly curved non-tubular tubulin-polymers in Toxoplasma. TgDCX deletion impairs conoid structure and parasite invasion. TgDCX contains two tubulin-binding domains: a partial P25α and the DCX/doublecortin domain. Orthologues are found in apicomplexans and their free-living relatives Chromera and Vitrella. Results: We report that isolated TgDCX-containing conoid fibers retain their pronounced curvature, but loss of TgDCX destabilizes the fibers. We crystallized and determined the 3D-structure of the DCX-domain, which is similar to those of human doublecortin and well-conserved among TgDCX orthologues. However, the orthologues vary widely in targeting to the conoid in Toxoplasma and in modulating microtubule organization in Xenopus cells. Several orthologues bind to microtubules in Xenopus cells, but only TgDCX generates short, strongly curved microtubule arcs. EM analysis shows microtubules decorated with TgDCX bundled into rafts, often bordered on one edge by a "C"-shaped incomplete tube. A Chromera orthologue closely mimics TgDCX targeting in Toxoplasma and binds to microtubules in Xenopus cells, but does not generate arcs or "C"-shaped tubes, and fails to rescue the defects of the TgDCX-knockout parasite. Conclusions: These observations suggest that species-specific features of TgDCX enable it to generate strongly curved tubulin-polymers to support efficient host-cell invasion. [ABSTRACT FROM AUTHOR]

ERYTHROCYTES, BLOOD platelets, BLOOD groups, ANTIGENS, and POLYMERASE chain reaction

Background: Genotyping has expanded the number red blood cell (RBC) and platelet (PLT) antigens that can readily be typed, but often represents an additional testing cost. The analysis of existing genomic data offers a cost-effective approach. We recently developed automated software (bloodTyper) for determination of RBC and PLT antigens from whole genome sequencing. Here we extend the algorithm to whole exome sequencing (WES).Study Design and Methods: Whole exome sequencing was performed on samples from 75 individuals. WES-based bloodTyper RBC and PLT typing was compared to conventional polymerase chain reaction (PCR) RHD zygosity testing and serologic and single-nucleotide polymorphism (SNP) typing for 38 RBC antigens in 12 systems (17 serologic and 35 SNPs) and 22 PLT antigens (22 SNPs). Samples from the first 20 individuals were used to modify bloodTyper to interpret WES followed by blinded typing of 55 samples.Results: Over the first 20 samples, discordances were noted for C, M, and N antigens, which were due to WES-specific biases. After modification, bloodTyper was 100% accurate on blinded evaluation of the last 55 samples and outperformed both serologic (99.67% accurate) and SNP typing (99.97% accurate) reflected by two Fyb and one N serologic typing errors and one undetected SNP encoding a Jknull phenotype. RHD zygosity testing by bloodTyper was 100% concordant with a combination of hybrid Rhesus box PCR and PCR-restriction fragment length polymorphism for all samples.Conclusion: The automated bloodTyper software was modified for WES biases to allow for accurate RBC and PLT antigen typing. Such analysis could become a routing part of future WES efforts. [ABSTRACT FROM AUTHOR]

PHASED array antennas, OPTICAL images, COHERENCE (Optics), BEAM steering, SILICON solar cells, and PHOTONICS

Recent advances in silicon photonics have enabled large-scale optical phased arrays for applications such as beam steering and directional light detection. However, to date, these results have only been applied to coherent light. Many applications, including passive imaging with natural illumination, require operation using incoherent and/or broadband light. Here, we implement an optical phased array designed for these applications using a planar, fractal, path length-matching architecture known as an "H-tree." We demonstrate electronic beamsteering and natural light imaging using this flat, broadband, photonic-integrated device. [ABSTRACT FROM AUTHOR]

PEDIATRIC emergency services, TEENAGE suicide, SUICIDE, SUICIDE prevention, and CONCEPT mapping

The purpose of this study was to include youth, parents, researchers, and clinicians in the identification of feasible and acceptable strategies for teen suicide screening in the pediatric emergency department (ED). Concept mapping methodology was used to elicit stakeholder responses. Regarding the most important result of suicide screening for teens in the pediatric ED, suicide prevention and education for parents, friends, and community members was rated easiest to implement, while short- and long-term follow-up and treatment was rated most important. In terms of successful suicide screening for teens in the pediatric ED, provision of resources and information was rated most feasible, and a safe, friendly, private screening environment was rated most important. The concept maps can be used to align suicide risk screening with the priorities and recommendations of pediatric ED stakeholders. [ABSTRACT FROM AUTHOR]