The Accuracy of Nonstandardized MELD/PELD Score Exceptions in the Pediatric Liver Allocation System.

BACKGROUND: In the United States, over half of pediatric candidates receive exceptions and status upgrades that increase their allocation model of end-stage liver disease/pediatric end-stage liver disease (MELD/PELD) score above their laboratory MELD/PELD score. We determined whether these "nonstandardized" MELD/PELD exceptions accurately depict true pretransplant mortality risk. METHODS: Using data from the Scientific Registry of Transplant Recipients, we identified pediatric candidates (<18 y of age) with chronic liver failure added to the waitlist between June 2016 and September 2021 and estimated all-cause pretransplant mortality with mixed-effects Cox proportional hazards models that treated allocation MELD/PELD and exception status as time-dependent covariates. We also estimated concordance statistics comparing the performance of laboratory MELD/PELD with allocation MELD/PELD. We then compared the proportion of candidates with exceptions before and after the establishment of the National Liver Review Board. RESULTS: Out of 2026 pediatric candidates listed during our study period, 403 (19.9%) received an exception within a week of listing and 1182 (58.3%) received an exception before delisting. Candidates prioritized by their laboratory MELD/PELD scores had an almost 9 times greater risk of pretransplant mortality compared with candidates who received the same allocation score from an exception (hazard ratio 8.69; 95% confidence interval, 4.71-16.03; P < 0.001). The laboratory MELD/PELD score without exceptions was more accurate than the allocation MELD/PELD score with exceptions (Harrell's c-index 0.843 versus 0.763). The proportion of patients with an active exception at the time of transplant decreased significantly after the National Liver Review Board was implemented (67.4% versus 43.4%, P < 0.001). CONCLUSIONS: Nonstandardized exceptions undermine the rank ordering of pediatric candidates with chronic liver failure.

Utility of geriatric assessments in evaluation of older adults for kidney transplantation.

BACKGROUND: While kidney transplantation has favorable outcomes in patients aged 65 years and older, many are not referred for evaluation despite having no contraindications. We wanted to determine whether incorporating geriatrics and geriatric assessments (GA), as part of kidney transplant evaluation at the University of Chicago Medicine, would help identify suitable candidates and improve transplantation outcomes among older adults. METHODS: Between 2012 and 2016, as part of their multi-disciplinary transplant evaluation, 171 patients underwent an initial GA with the study geriatrician, who rated them on a five-point scale from "poor" to "excellent," and presented their cases to multidisciplinary transplant review meetings. Patients were followed until June 1st, 2021. Predictor variables included geriatric recommendation, clinical characteristics, and demographics. Outcomes of interest were mortality, receipt of transplant, and waitlist placement. RESULTS: Compared to patients rated "poor," "marginal," or "fair," we found that patients that the geriatrician recommended as "good" or "excellent" were more likely to be waitlisted and receive a transplant. Favorably rated patients were also less likely to be removed from the waitlist due to becoming medically unfit, meaning worsening medical morbidity, frailty, and cognitive status. CONCLUSION: Including geriatricians to perform GAs as part of the transplant evaluation process can help identify suitable elderly candidates.

Where Do I Fit In? A Perspective on Challenges Faced by Asian American Medical Students.

Asian American medical students (AAMSs) face significant bias in the medical learning environment and are more likely than White students to perceive their school climate negatively. Little is known about the factors that contribute to AAMSs' negative experiences. This perspective aims to describe AAMSs' experiences with diversity and inclusion efforts using survey data from a midwest regional conference, Asians in Medicine: A Conference on Advocacy and Allyship. AAMS respondents reported feeling excluded from diversity and inclusion efforts and conference participants advocated for institutional culture and climate assessments stratified by race and disaggregated into Asian subgroups.

The LysR-type transcriptional regulator, CidR, regulates stationary phase cell death in Staphylococcus aureus.

The Staphylococcus aureus LysR-type transcriptional regulator, CidR, activates the expression of two operons including cidABC and alsSD that display pro- and anti-death functions, respectively. Although several investigations have focused on the functions of different genes associated with these operons, the collective role of the CidR regulon in staphylococcal physiology is not clearly understood. Here we reveal that the primary role of this regulon is to limit acetate-dependent potentiation of cell death in staphylococcal populations. Although both CidB and CidC promote acetate generation and cell death, the CidR-dependent co-activation of CidA and AlsSD counters the effects of CidBC by redirecting intracellular carbon flux towards acetoin formation. From a mechanistic standpoint, we demonstrate that CidB is necessary for full activation of CidC, whereas CidA limits the abundance of CidC in the cell.