Treatment of Hypercalcemic Hyperparathyroidism After Kidney Transplantation Is Associated With Improved Allograft Survival

BACKGROUND

Hyperparathyroidism (HPT) and malignancy are the most common causes of hypercalcemia. Among kidney transplant (KT) recipients, hypercalcemia is mostly caused by tertiary HPT. Persistent tertiary HPT after KT is associated with allograft failure. Previous studies on managing tHPT were subjected to survivor treatment selection bias; as such, the impact of tertiary HPT treatment on allograft function remained unclear. We aim to assess the association between hypercalcemic tertiary HPT treatment and kidney allograft survival.

MATERIALS AND METHODS

We identified 280 KT recipients (2015-2019) with elevated post-KT adjusted serum calcium and parathyroid hormone (PTH). KT recipients were characterized by treatment: cinacalcet, parathyroidectomy, or no treatment. Time-varying Cox regression with delayed entry at the time of first elevated post-KT calcium was conducted, and death-censored and all-cause allograft failure were compared by treatment groups.

RESULTS

Of the 280 recipients with tHPT, 49 underwent PTx, and 98 received cinacalcet. The median time from KT to first elevated calcium was 1 month (IQR: 0-4). The median time from first elevated calcium to receiving cinacalcet and parathyroidectomy was 0(IQR: 0-3) and 13(IQR: 8-23) months, respectively. KT recipients with no treatment had shorter dialysis vintage (P = .017) and lower PTH at KT (P = .002), later onset of hypercalcemia post-KT (P < .001). Treatment with PTx (adjusted hazard ratio (aHR) = 0.18, 95%CI 0.04-0.76, P = .02) or cinacalcet (aHR = 0.14, 95%CI 0.004-0.47, P = .002) was associated with lower risk of death-censored allograft failure. Moreover, receipt of PTx (aHR = 0.28, 95%CI 0.12-0.66, P < .001) or cinacalcet (aHR = 0.38, 95%CI 0.22-0.66, P < .001) was associated with lower risk of all-cause allograft failure.

CONCLUSIONS

This study demonstrates that treatment of hypercalcemic tertiary HPT post-KT is associated with improved allograft survival. Although these findings are not specific to hypercalcemia of malignancy, they do demonstrate the negative impact of hypercalcemic tertiary HPT on kidney function. Hypercalcemic HPT should be screened and aggressively treated post-KT.

Racial Disparities in Hidradenitis Suppurativa-Related Pain: A Cross-sectional Analysis

Racial disparities in pain management for chronic diseases persist in the United States. However, no research exists assessing racial disparities in related pain. This study aimed to identify racial differences in hidradenitis suppurativa (HS)-related pain scores. Additionally, we characterized patient satisfaction with pain management. Further research is needed to evaluate if systemic or health care provider biases contribute to racial differences in HS-related pain management.

Perpetuating Disparity: Failure of the Kidney Transplant System to Provide the Most Kidney Transplants to Communities With the Greatest Need

BACKGROUND

The burden of end-stage kidney disease (ESKD) and kidney transplant rates vary significantly across the United States. This study aims to examine the mismatch between ESKD burden and kidney transplant rates from a perspective of spatial epidemiology.

METHODS

US Renal Data System data from 2015 to 2017 on incident ESKD and kidney transplants per 1000 incident ESKD cases was analyzed. Clustering of ESKD burden and kidney transplant rates at the county level was determined using local Moran's I and correlated to county health scores. Higher percentile county health scores indicated worse overall community health.

RESULTS

Significant clusters of high-ESKD burden tended to coincide with clusters of low kidney transplant rates, and vice versa. The most common cluster type had high incident ESKD with low transplant rates (377 counties). Counties in these clusters had the lowest overall mean transplant rate (61.1), highest overall mean ESKD incidence (61.3), and highest mean county health scores percentile (80.9%, P <0.001 vs all other cluster types). By comparison, counties in clusters with low ESKD incidence and high transplant rates (n=359) had the highest mean transplant rate (110.6), the lowest mean ESKD incidence (28.9), and the lowest county health scores (20.2%). All comparisons to high-ESKD/low-transplant clusters were significant at P value <0.001.

CONCLUSION

There was a significant mismatch between kidney transplant rates and ESKD burden, where areas with the greatest need had the lowest transplant rates. This pattern exacerbates pre-existing disparities, as disadvantaged high-ESKD regions already suffer from worse access to care and overall community health, as evidenced by the highest county health scores in the study.

Inter-Rater Reliability and Correlation of L1 Hounsfield Unit Measurements with DXA Scores

INTRODUCTION

While prior studies have generally reported rigorous protocols using prespecified CT scanner settings for HU measurements, the present study sought to report on the correlation between DXA and HUs recorded using several CT scanners with varying sequences, simulating measurements performed in "real-world" hospital and Emergency Department (ED) settings.

METHODOLOGY

Six raters performed HU measurements of trabecular bone at the L1 vertebral body for forty consecutive patients on Phillips and General Electric (GE) abdominal CT scans obtained between 2017 and 2021. Inter-rater reliability of the HU measurements and their correlations with recorded DXA-based bone assessments were determined. Correlation coefficients were calculated for the HU measurements between scanner vendors as well as for the CT HUs with each DXA measurement.

RESULTS

The ICC for L1 HUs read on the Phillips and GE scanners were 0.85 and 0.82, respectively, indicating excellent agreement. The correlation coefficient for the mean HUs on the Phillips and GE scanners was 0.92, also indicating excellent correlation. For both scanner vendors, the HU values most closely correlated with the total femur and femoral neck T-scores.

CONCLUSIONS

HU values recorded on a Phillips and GE scanner both demonstrated excellent inter-rater reliability. Correlations were strongest between L1 HU values and total femur DXA T-scores. Readily available abdominal CT image data across multiple hospital settings can be utilized by providers of varying level of imaging interpretation expertise to determine vertebral body Hounsfield units that may help identify osteoporosis risk without additional radiation exposure or cost.

Abnormal time-zero histology is predictive of kidney transplant outcomes

Time-zero biopsies can detect donor-derived lesions at the time of kidney transplantation, but their utility in predicting long-term outcomes is unclear under the updated Kidney Allocation System. We conducted a single-center retrospective cohort study of 272 consecutive post-reperfusion time-zero biopsies. We tested the hypothesis that abnormal time-zero histology is a strong indicator of donor quality that increases the precision of the kidney donor profile index (KDPI) score to predict long-term outcomes. We detected abnormal biopsies in 42% of the cohort, which were independently associated with a 1.2-fold increased hazard for a composite of acute rejection, allograft failure, and death after adjusting for clinical characteristics including KDPI. By Kaplan-Meier analysis, the relationship between abnormal time-zero histology and the composite endpoint was only significant in the subgroup of deceased donor kidney transplants with KDPI scores > 35. Abnormal time-zero histology, particularly vascular intimal fibrosis and arteriolar hyalinosis scores, was independently associated with lower 12-month estimated GFR. In conclusion, abnormal time-zero histology is relatively common and identifies a group of kidney recipients at increased risk for worse long-term outcomes. Further studies are needed to determine the optimal patient population in which to deploy time-zero biopsies as an additional surveillance tool. This article is protected by copyright. All rights reserved.

Evaluation of Community-Level Vulnerability and Racial Disparities in Living Donor Kidney Transplant

Importance

Living donor kidney transplant (LDKT) is the ideal treatment for end-stage kidney disease, but racial disparities in LDKT have increased over the last 2 decades. Recipient clinical and social factors do not account for LDKT racial inequities, although comprehensive measures of community-level vulnerability have not been assessed.

Objective

To determine if racial disparities persist in LDKT independent of community-level vulnerability.

Design, Setting, and Participants

This retrospective, multicenter, cross-sectional study included data from 19 287 adult kidney-only transplant recipients in the Scientific Registry of Transplant Recipients. The study included individuals who underwent transplant between January 1 and December 31, 2018.

Exposures

Recipient race and the 2018 US Centers for Disease Control and Prevention Social Vulnerability Index (SVI). Census tract-level SVI data were linked to census tracts within each recipient zip code. The median SVI measure among the census tracts within a zip code was used to describe community-level vulnerability.

Main Outcomes and Measures

Kidney transplant donor type (deceased vs living). Modified Poisson regression was used to evaluate the association between SVI and LDKT, and to estimate LDKT likelihood among races, independent of community-level vulnerability and recipient-level characteristics.

Results

Among 19 287 kidney transplant recipients, 6080 (32%) received LDKT. A total of 11 582 (60%) were male, and the median (interquartile range) age was 54 (43-63) years. There were 760 Black LDKT recipients (13%), 4865 White LDKT recipients (80%), and 455 LDKT recipients of other races (7%; American Indian, Asian, multiracial, and Pacific Islander). Recipients who lived in communities with higher SVI (ie, more vulnerable) had lower likelihood of LDKT compared with recipients who lived in communities with lower SVI (ie, less vulnerable) (adjusted relative risk [aRR], 0.97; 95% CI, 0.96-0.98; P < .001). Independent of community-level vulnerability, compared with White recipients, Black recipients had 37% lower likelihood (aRR, 0.63; 95% CI, 0.59-0.67; P < .001) and recipients of other races had 24% lower likelihood (aRR, 0.76; 95% CI, 0.70-0.82; P < .001) of LDKT. The interaction between SVI and race was significant among Black recipients, such that the disparity in LDKT between Black and White recipients increased with greater community-level vulnerability (ratio of aRRs, 0.67; 95% CI, 0.51-0.87; P = .003).

Conclusions and Relevance

Community-level vulnerability is associated with access to LDKT but only partially explains LDKT racial disparities. The adverse effects of living in more vulnerable communities were worse for Black recipients. The interaction of these constructs is worrisome and suggests evaluation of other health system factors that may contribute to LDKT racial disparities is needed.

Association Between Pentosan Polysulfate Sodium and Retinal Disorders

Importance

Case series have identified a macular condition hypothesized to be associated with the use of pentosan polysulfate sodium (PPS). Observational studies seeking to quantify this association have yielded equivocal results.

Objective

To estimate the association between PPS exposure and maculopathy.

Design, Setting, and Participants

This disproportionality analysis was conducted using the US Food and Drug Administration Adverse Event Reporting System from January 2013 through June 2020.

Exposure

Adverse event reports for pentosan polysulfate were selected and compared with adverse event reports associated with drugs taken for the following indications: interstitial cystitis, cystitis, bladder disorder, or bladder pain.

Main Outcome Measures

Retinal adverse events were identified using the retinal disorders Standardized Medical Dictionary for Regulatory Activities (MedDRA) Query, which includes conditions associated with retinal damage attributable to blockage of its blood supply, nutritional deficiencies, toxins, and diseases affecting the retina.

Results

There were 2775 reports available for analysis in the PPS group (of which 1966 were for women [70.9%]) and 6833 reports in the other drugs group (of which 4036 [59.1%] were for women). The proportion of adverse events for any macular event relative to all other events was elevated for the users of PPS compared with those using other interstitial cystitis and bladder pain drugs (proportionate reporting ratio [PRR], 1.21 [95% CI, 1.01-1.44]). With respect to specific retinal conditions, macular degeneration (20 [0.8%] vs 15 [0.2%]), maculopathy (83 [3.4%] vs 2 [0.03%]), retinal dystrophy (3 [0.1%] vs 0), retinal injury (5 [0.2%] vs 0), and retinal toxicity (3 [0.1%] vs 0) were proportionately more common among users of PPS compared with those using other interstitial cystitis and bladder pain drugs, respectively.

Conclusions and Relevance

The results of the current study add to the growing evidence that PPS use is associated with an increased risk of maculopathy. Studies that rule out prevalent retinal abnormalities prior to the initiation of PPS would strengthen the current body of literature.

Achieving Vancomycin Troughs Within Goal Range in Low Birth Weight Neonates

OBJECTIVE

Vancomycin is commonly used in the neonatal population to treat Gram-positive bacterial infections. Despite frequent use, consensus on the ideal dosing regimen in low birth weight (LBW) neonates is lacking. The objective of this research is to determine how frequently vancomycin troughs within goal range (10-20 mg/L) are achieved with empiric dosing in critically ill neonates and infants weighing less than 2500 g.

METHODS

This retrospective review evaluated LBW infants who were admitted to a level IV NICU from January 2015 to December 2016. Patients were included if they had a vancomycin trough sample collected at steady state (after at least 3 doses). Three trough cohorts (subtherapeutic: <10 mg/L, therapeutic: 10-20 mg/L, and supratherapeutic: >20 mg/L) were compared with 1-way ANOVA for continuous data and a chi-square analysis for categorical data.

RESULTS

A total of 74 patients were included, with a mean birth weight (BW) of 819.7 ± 355.4 g and a mean gestational age (GA) of 26.4 ± 3.7 weeks. Only 27 patients (36.5%) had therapeutic vancomycin trough concentrations. Subtherapeutic troughs were recorded in 40 patients (54.1%), while supratherapeutic troughs were recorded in 7 patients (9.5%). Although there was no difference between the initial dose, initial frequency was significantly different between cohorts (p = 0.04).

CONCLUSION

Empiric dosing regimens do not produce vancomycin troughs within the goal range in most LBW patients.

Repeat Attending Exposure Influences Operative Autonomy in Endocrine Surgical Procedures

PURPOSE

There is concern that graduating surgery residents are not prepared for independent practice. This study aimed to identify predictors of performance, autonomy, and readiness for independence ratings of trainees by attendings for thyroidectomy and parathyroidectomy with respect to repeated resident-attending exposure. We hypothesized that increased exposure with a particular attending increases resident autonomy.

METHODS

All residents and faculty at a single institution performing parathyroidectomy or thyroidectomy were invited to complete an operative performance evaluation at case competition using the Zwisch scale to measure performance and autonomy for individual operative steps. In addition, each survey evaluated the trainee's readiness for practice in a straightforward procedure as a binary variable. Categorical variables were evaluated via Chi-squared or Fisher's exact tests and ordinal variables were evaluated with Wilcoxon or Kruskal-Wallis tests. Multivariable analysis was conducted with random effects logistic regression, and learning curves were generated for each procedure.

RESULTS

Operative performance evaluations were obtained from 36 individual learners and 6 faculty members, with a total of 145 evaluations for parathyroidectomy and 116 for thyroidectomy. On bivariate analysis, readiness for practice ratings was significantly associated with increasing chronologic procedure number, but not resident gender or case difficulty. The multivariable model demonstrated that increasing chronologic procedure number, while a significant predictor without accounting for exposure, did not remain a significant predictor of practice-readiness for parathyroidectomy when accounting for resident-attending exposure. Bivariate analysis comparing resident and attending ratings showed no difference between the 2, but there were significant differences in autonomy and performance scores for both groups of raters. Trainees rated by attendings as independence ready completed a median of 7 parathyroidectomies and 5 thyroidectomies. Descriptive learning curves generated serve as a model of the multistate nature that residents undergo when moving from novice to proficiency.

CONCLUSIONS

Not surprisingly, the more operations residents perform with a single attending, the higher their ratings for performance and autonomy from that individual, with increased exposure allowing improved performance with less attending autonomy. By contrast, our data also show that repeated exposure between resident and attending may confound the use of procedural numbers alone when predicting resident ability in the operating room.

Patient-reported cognitive complaints in older adults with gastrointestinal malignancies at diagnosis- Results from the Cancer & Aging Resilience Evaluation (CARE) study

OBJECTIVES

Patient-reported cognitive complaint (CI) is poorly described in older adults with cancer. The purpose of this study was to quantify the prevalence and examine the associations of patient-reported CI in older adults with gastrointestinal (GI) malignancies at diagnosis.

MATERIALS AND METHODS

Using participants ≥60 years with GI malignancies from the Cancer & Aging Resilience Evaluation (CARE) Registry that underwent a Geriatric Assessment (GA), we examined CI using the Patient-Reported Outcomes Measurement Information System (PROMIS®) Short Form 4a Cognitive Function. Cognition scores were dichotomized into normal (scores of 15-20) and impaired (4-14), and bivariate and multivariate analyses were used to examine associations.

RESULTS

A total of 264 participants with GI malignancy were included, mean age of 70.0 ± 7.1, 55.7% male, pancreatic cancer was the most common cancer (24.2%) and majority were stage III/IV (68.2%). 29.3% of participants endorsed CI. CI was not associated with demographic and clinical domains, but was associated with many GA impairments including instrumental Activities of Daily Living (iADL) impairment (adjusted odds ratio [aOR] 6.0, 95% confidence interval 3.0-11.8), falls (aOR 2.7, 1.4-5.4), anxiety (aOR 10.3, 5.2-20.4), and depression (aOR 10.2, 5.2-20.4). CI was also associated with reduced global mental (aOR 18.7, 8.1-42.2) and physical (aOR 4.7, 2.4-8.9) quality of life, and prior hospitalizations (aOR 2.4, 1.2-4.8).

CONCLUSION

We found a high prevalence of patient-reported CI in older adults with GI malignancies that was associated with increased GA impairments, reduced health-related quality of life, and increased healthcare utilization.

Distracted Driving and Risk of Crash or Near-Crash Involvement Among Older Drivers Using Naturalistic Driving Data With a Case-Crossover Study Design

BACKGROUND

The purpose of this study was to examine the association between secondary task involvement and risk of crash and near-crash involvement among older drivers using naturalistic driving data.

METHODS

Data from drivers aged ≥70 years in the Strategic Highway Research Program (SHRP2) Naturalistic Driving Study database was utilized. The personal vehicle of study participants was equipped with four video cameras enabling recording of the driver and the road environment. Secondary task involvement during a crash or near-crash event was compared to periods of noncrash involvement in a case-crossover study design. Conditional logistic regression was used to generate odds ratios (ORs) and 95% confidence intervals (CI).

RESULTS

Overall, engaging in any secondary task was not associated with crash (OR = 0.94, 95% CI 0.68-1.29) or near-crash (OR = 1.08, 95% CI 0.79-1.50) risk. The risk of a major crash event with cell phone use was 3.79 times higher than the risk with no cell phone use (95% CI 1.00-14.37). Other glances into the interior of the vehicle were associated with an increased risk of near-crash involvement (OR = 2.55, 95% CI 1.24-5.26). Other distractions external to the vehicle were associated with a decreased risk of crash involvement (OR = 0.53, 95% CI 0.30-0.94). Interacting with a passenger and talking/singing were not associated with crash or near-crash risk.

CONCLUSIONS

Older drivers should avoid any cell phone use and minimize nondriving-related eye glances towards the interior of the vehicle while driving. Certain types of events external to the vehicle are associated with a reduced crash risk among older drivers.

Disparity in access to kidney allograft offers among transplant candidates with human immunodeficiency virus

BACKGROUND

Despite a survival benefit from transplantation and acceptable outcomes, patients with human immunodeficiency virus (HIV+) face barriers to kidney transplantation. Little is known about the acceptance or decline of organ offers on their behalf because waitlist registry data do not include HIV serostatus.

METHODS

We performed a retrospective cohort study using match run data from the Organ Procurement and Transplantation Network, including every kidney offer from May 1, 2007, to July 3, 2013. HIV and hepatitis C virus (HCV) serostatus were obtained by merging the match run with clinical data from a large dialysis provider. We used Cox proportional hazards modeling to evaluate differences in time to the first organ offer and to transplantation. A total of 35 646 uninfected, 2213 HCV+, 418 HIV+, and 71 HIV+/HCV+ candidates received organ offers during the study period.

RESULTS

Compared to uninfected candidates, HIV+ candidates had a significantly lower likelihood of receiving a first offer (adjusted hazard ratio [aHR] 0.88, 95% confidence interval [CI] 0.79-0.99) and undergoing transplantation (aHR 0.82, 95% CI: 0.68-0.98) after receiving a first offer; HCV+ candidates had a similar likelihood of receiving a first offer (aHR 0.98, 95% CI: 0.92-1.03) and greater likelihood of transplantation after receiving a first offer (aHR 1.23, 95% CI: 1.12-1.36).

CONCLUSIONS

HIV+ candidates had a significantly longer wait until their first organ offer and to transplantation. Efforts to increase their access to transplantation are needed.

Visual Sensory and Visual-Cognitive Function and Rate of Crash and Near-Crash Involvement Among Older Drivers Using Naturalistic Driving Data

Purpose

An innovative methodology using naturalistic driving data was used to examine the association between visual sensory and visual-cognitive function and rates of future crash or near-crash involvement among older drivers.

Methods

The Strategic Highway Research Program (SHRP2) Naturalistic Driving Study was used for this prospective analysis. The sample consisted of N = 659 drivers aged ≥70 years and study participation lasted 1 or 2 years for most participants. Distance and near visual acuity, contrast sensitivity, peripheral vision, visual processing speed, and visuospatial skills were assessed at baseline. Crash and near-crash involvement were based on video recordings and vehicle sensors. Poisson regression models were used to generate crude and adjusted rate ratios (RRs) and 95% confidence intervals, while accounting for person-miles of travel.

Results

After adjustment, severe impairment of the useful field of view (RR = 1.33) was associated with an increased rate of near-crash involvement. Crash, severe crash, and at-fault crash involvement were associated with impaired contrast sensitivity in the worse eye (RRs = 1.38, 1.54, and 1.44, respectively) and far peripheral field loss in both eyes (RRs = 1.74, 2.32, and 1.73, respectively).

Conclusions

Naturalistic driving data suggest that contrast sensitivity in the worse eye and far peripheral field loss in both eyes elevate the rates of crash involvement, and impaired visual processing speed elevates rates of near-crash involvement among older drivers. Naturalistic driving data may ultimately be critical for understanding the relationship between vision and driving safety.

Access to Kidney Transplantation among HIV-Infected Waitlist Candidates

BACKGROUND AND OBJECTIVES

Kidney transplantation among HIV-infected patients with ESRD confers a significant survival benefit over remaining on dialysis. Given the high mortality burden associated with dialysis, understanding access to kidney transplantation after waitlisting among HIV+ candidates is warranted.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data from the Scientific Registry of Transplant Recipients were linked to Intercontinental Marketing Statistics pharmacy fills (January 1, 2001 to October 1, 2012) so that we could identify and study 1636 HIV+ (defined as having filled one or more antiretroviral medications unique to HIV treatment) and 72,297 HIV- kidney transplantation candidates.

RESULTS

HIV+ waiting list candidates were more often young (<50 years old: 62.7% versus 37.6%; P<0.001), were more often men (75.2% versus 59.3%; P<0.001), were more often black (73.6% versus 27.9%; P<0.001), had longer time on dialysis (years: 2.5 versus 0.8; P<0.001), were more often coinfected with hepatitis C virus (9.0% versus 3.9%; P<0.001), and were less likely to remain active on the waiting list (37.7% versus 49.4%; P<0.001). Waitlist mortality among HIV+ candidates was similar compared with HIV- candidates (adjusted hazard ratio, 1.03; 95% confidence interval, 0.89 to 1.20; P=0.67). In contrast, likelihood of living donor kidney transplantation was 47% lower (adjusted hazard ratio, 0.53; 95% confidence interval, 0.44 to 0.64; P<0.001), and there was a trend toward lower likelihood of deceased donor kidney transplantation (adjusted hazard ratio, 0.87; 95% confidence interval, 0.74 to 1.01; P=0.07) compared with in HIV- candidates.

CONCLUSIONS

Our findings highlight the need for additional study to better understand disparities in access to kidney transplantation, particularly living donor kidney transplantation, among HIV+ kidney waitlist candidates.

Center-Level Experience and Kidney Transplant Outcomes in HIV-Infected Recipients

Excellent outcomes among HIV+ kidney transplant (KT) recipients have been reported by the NIH consortium, but it is unclear if experience with HIV+ KT is required to achieve these outcomes. We studied associations between experience measures and outcomes in 499 HIV+ recipients (SRTR data 2004-2011). Experience measures examined included: (1) center-level participation in the NIH consortium; (2) KT experiential learning curve; and (3) transplant era (2004-2007 vs. 2008-2011). There was no difference in outcomes among centers early in their experience (first 5 HIV+ KT) compared to centers having performed >6 HIV+ KT (GS adjusted hazard ratio [aHR]: 1.05, 95% CI: 0.68-1.61, p = 0.82; PS aHR: 0.93; 95% CI: 0.56-1.53, p = 0.76), and participation in the NIH-study was not associated with any better outcomes (GS aHR: 1.08, 95% CI: 0.71-1.65, p = 0.71; PS aHR: 1.13; 95% CI: 0.68-1.89, p = 0.63). Transplant era was strongly associated with outcomes; HIV+ KTs performed in 2008-2011 had 38% lower risk of graft loss (aHR: 0.62; 95% CI: 0.42-0.92, p = 0.02) and 41% lower risk of death (aHR: 0.59; 95% CI: 0.39-0.90, p = 0.01) than that in 2004-2007. Outcomes after HIV+ KT have improved over time, but center-level experience or consortium participation is not necessary to achieve excellent outcomes, supporting continued expansion of HIV+ KT in the US.

Sources: Oil: A Cultural and Geographic Encyclopedia of Black Gold

In the winter of 2015, as this review is being written, the price of gasoline is plummeting in the United States and what this will mean for the individual, community, and country for the immediate future but also in years to come is unknown. There are a wide range of implications in politics, economics, and international relations as well as effects on what the individual pays for everyday groceries. It is therefore important that libraries provide their communities with the resources that include information and discussion on how energy and its monetary value interact with society.

A National Study of Outcomes among HIV-Infected Kidney Transplant Recipients

Kidney transplantation is a viable treatment for select patients with HIV and ESRD, but data are lacking regarding long-term outcomes and comparisons with appropriately matched HIV-negative patients. We analyzed data from the Scientific Registry of Transplant Recipients (SRTR; 2002-2011): 510 adult kidney transplant recipients with HIV (median follow-up, 3.8 years) matched 1:10 to HIV-negative controls. Compared with HIV-negative controls, HIV-infected recipients had significantly lower 5-year (75.3% versus 69.2%) and 10-year (54.4% versus 49.8%) post-transplant graft survival (GS) (hazard ratio [HR], 1.37; 95% confidence interval [95% CI], 1.15 to 1.64; P<0.001) that persisted when censoring for death (HR, 1.43; 95% CI, 1.12 to 1.84; P=0.005). However, compared with HIV-negative/hepatitis C virus (HCV)-negative controls, HIV monoinfected recipients had similar 5-year and 10-year GS, whereas HIV/HCV coinfected recipients had worse GS (5-year: 64.0% versus 52.0%, P=0.02; 10-year: 36.2% versus 27.0%, P=0.004 [HR, 1.38; 95% CI, 1.08 to 1.77; P=0.01]). Patient survival (PS) among HIV-infected recipients was 83.5% at 5 years and 51.6% at 10 years and was significantly lower than PS among HIV-negative controls (HR, 1.34; 95% CI, 1.08 to 1.68; P<0.01). However, PS was similar for HIV monoinfected recipients and HIV-negative/HCV-negative controls at both times. HIV/HCV coinfected recipients had worse PS compared with HIV-negative/HCV-infected controls (5-year: 67.0% versus 78.6%, P=0.007; 10-year: 29.3% versus 56.23%, P=0.002 [HR, 1.57; 95% CI, 1.11 to 2.22; P=0.01]). In conclusion, HIV-negative and HIV monoinfected kidney transplant recipients had similar GS and PS, whereas HIV/HCV coinfected recipients had worse outcomes. Although encouraging, these results suggest caution in transplanting coinfected patients.

Trauma center resource consumption and mortality

Studies suggesting that increased trauma center (TC) patient volume leads to improved patient outcomes have produced inconsistent results. It is possible that the combination of TC patient volume and TC resources has a greater influence over outcomes than TC volume alone. Patients admitted to 131 TCs from 1994 to 2002 were included. TC density was calculated as the ratio of TC adult beds to patient volume and categorized into quartiles. Adjusted risk ratios (RRs) and 95 per cent confidence intervals (CIs) compared mortality of groups (Q1 [low density]-Q4 [high density]). Relative to Q4 TCs, for penetrating injuries with ISS < 15, elevated mortality was seen for Q2 (low-moderate density) TCs (RR 1.47, CI 1.09-1.99) and Q3 (high-moderate density) TCs (RR 1.81, CI 1.36-2.41); but for ISS > or = 15, mortality was lowest for Q1 (RR 0.78, CI 0.68-0.89). For blunt injury, mortality was similar for low- and high-density TCs but elevated for low-moderate- and high-moderate-density TCs. Mortality at low-density TCs was decreased overall and for penetrating injuries specifically but similar for blunt injuries when compared with high-density TCs. Enhanced resources measurements will clarify the relationship between patient volume, resources, and mortality.

Motor vehicle crash-related mortality is associated with prehospital and hospital-based resource availability

BACKGROUND

To date, attempts to assess the relationship between motor vehicle collision (MVC)-related mortality and medical resources availability have largely been unsuccessful.

METHODS

Information regarding sociodemographic characteristics, prehospital resources, and hospital-based resources for each county (n = 67) in the state of Alabama was obtained. MVC-related mortality rates (deaths per 1,000 collisions) by county were calculated and compared according to prehospital and hospital-based resource availability within each county after correcting for sociodemographic factors.

RESULTS

Counties with 24-hour availability of a general surgeon, orthopedic surgeon, neurosurgeon, computed tomographic scanner, and operating room were shown to have decreased MVC-related mortality (relative risk [RR], 0.88). The same was true for those counties with hospitals classified as Level I-II (RR, 0.71) and Level III-IV (RR, 0.83) trauma centers compared with counties with no trauma centers.

CONCLUSION

Appropriate, readily available hospital-based resources are associated with lower MVC-related mortality rates. This information may be useful in trauma system planning and development.

Effect of passive stretching on the wasting of muscle in the critically ill

This study examine whether muscle wasting in critically ill patients can be prevented by passive stretching alone in the absence of contractile activity. Five critically ill patients who required a complete neuromuscular blockade for 7 days of ventilator support were studied. One leg of each patient was treated with continuous passive motion (CPM) for three 3-h periods daily while the other leg received only routine nursing care. Fiber atrophy was prevented in the more severely ill patients and there was a slight gain in fiber area (mean increase, +11%) in the CPM limb compared with the control leg, which decreased (mean decrease, -35%) over 7 days. Fiber area was preserved in both fiber types but was more pronounced in type I muscle fibers. Protein loss was significantly less in the CPM limb. There was a significantly greater increase in wet weight per mg DNA in the control limb. However, as an index of wasting, the ratio of protein to DNA decreased similarly in both limbs. Passive stretching can preserve the architecture of muscle fibers. Whether it can prevent muscle wasting remains uncertain.

Immunohistochemical and biochemical indicators of muscle damage in vitro: the stability of control muscle and the effects of dinitrophenol and calcium ionophore

The biochemical, histological and ultrastructural effects of 2,4-dinitrophenol and the calcium ionophore, A23187, on rat soleus muscle incubated in vitro have been examined to test the hypothesis that immunohistochemical techniques can be used to recognize early structural features of fibre damage. In control muscles, despite mild glycogen depletion and a mild reduction in protein synthetic rate in the central portion of the muscle, fibres throughout the muscle appear to be viable with normal cytoskeletal and contractile protein architecture, normal concentrations of high energy phosphates and no creatine kinase efflux. Dinitrophenol causes rapid creatine kinase efflux, extensive loss of immunolabelling for desmin and dystrophin, and abnormal myosin immunolabelling. Creatine kinase efflux and the changes in desmin and dystrophin are reduced by the exclusion of calcium. A23187 causes more gradual creatine kinase efflux associated with changes in myosin immunolabelling, but loss of desmin and dystrophin immunolabelling is restricted to a few of the most peripheral fibres. The results suggest that immunohistochemical methods can be used to reveal differences in the intracellular mechanisms of muscle damage. Although both dinitrophenol and A23187 may act, in part, through calcium-mediated processes, their effects on cytoskeletal proteins differ. Creatine kinase efflux after A23187 may not be due to gross sarcolemmal damage.

Characteristics of a glutamine carrier in skeletal muscle have important consequences for nitrogen loss in injury, infection, and chronic disease

A carrier for glutamine, identified in rat muscle, has properties in terms of kinetics, ion dependence and hormone sensitivity, and effects of endotoxin and branched-chain aminoacids that point to an important function in the control of whole-body aminoacid metabolism. The existence of a link between the size of the glutamine pool in muscle and the rate of muscle protein synthesis raises possibilities for therapeutic interventions to limit protein loss in injury, sepsis, and chronic disease.