Faculty Bibliography

BACKGROUND:Most hepatitis delta virus (HDV) prevalence estimates from the United States are >10 years old, and HDV has shown significant temporal variation in other populations. HDV-hepatitis B virus (HBV) dual infection progresses rapidly, has more complications, and has a different treatment regimen than HBV infection alone. Accurate estimates of prevalence and risk factors are important to help clinicians decide who to screen. METHODS:Injection drug users in Baltimore, Maryland, who were positive for HBV serologic markers were tested for hepatitis delta antibody (HDAb) at 2 time periods: 1988-1989 (194 participants) and 2005-2006 (258 participants). Those who were HDAb positive in 2005-2006, plus a random sample of HDAb negative, HBV-positive participants were tested for HDV RNA, HBV DNA, and HCV RNA. Characteristics associated with HDV exposure and viremia were identified. RESULTS:HDV prevalence declined from 15% in 1988-1989 to 11% in 2005-2006. Among those with chronic HBV infection, prevalence increased from 29% (14 of 48 participants) to 50% (19 of 38 participants) (P=.05). Visiting a "shooting gallery" (a location where people gather to inject illegal drugs) was a strong correlate of HDAb positivity (relative risk, 3.08; P=.01). Eight (32%) of those who were HDAb positive had HDV viremia. Viremic participants had elevated liver enzyme levels and more emergency room visits. CONCLUSIONS:The temporal increase in HDV prevalence among those with chronic HBV infection is troubling; understanding this change should be a priority to prevent the burden from increasing.

BACKGROUND:Surgeons frequently struggle to determine patient suitability for liver transplantation. Objective and comprehensive measures of overall burden of disease, such as sarcopenia, could inform clinicians and help avoid futile transplantations. STUDY DESIGN/METHODS:The cross-sectional area of the psoas muscle was measured on CT scans of 163 liver transplant recipients. After controlling for donor and recipient characteristics using Cox regression models, we described the relationship between psoas area and post-transplantation mortality. RESULTS:Psoas area correlated poorly with Model for End-Stage Liver Disease score and serum albumin. Cox regression revealed a strong association between psoas area and post-transplantation mortality (hazard ratio = 3.7/1,000 mm(2) decrease in psoas area; p < 0.0001). When stratified into quartiles based on psoas area (holding donor and recipient characteristics constant), 1-year survival ranged from 49.7% for the quartile with the smallest psoas area to 87.0% for the quartile with the largest. Survival at 3 years among these groups was 26.4% and 77.2%, respectively. The impact of psoas area on survival exceeded that of all other covariates in these models. CONCLUSIONS:Central sarcopenia strongly correlates with mortality after liver transplantation. Such objective measures of patient frailty, such as sarcopenia, can inform clinical decision making and, potentially, allocation policy. Additional work is needed develop valid and clinically relevant measures of sarcopenia and frailty in liver transplantation.

BACKGROUND:Blood type AB kidney transplant candidates have the shortest waiting times, yet the current allocation system allows allocation of type A donor kidneys to type AB recipients. STUDY DESIGN/METHODS:United Network for Organ Sharing/Organ Procurement and Transplantation Network data between 1995 and 2004, retrospective observational study. SETTING & PARTICIPANTS/METHODS:189,773 candidates listed for kidney-only transplant; 93,604 kidneys transplanted, 15,580 kidneys discarded. PREDICTOR/METHODS:Blood type and demographic/clinical variables. OUTCOMES & MEASUREMENTS/METHODS:The extent of disparities in waiting times and concurrent differences in recovery, discard, live donor, and deceased donor transplant rates. RESULTS:Blood type O, A, B, and AB candidates constituted 48%, 34%, 14%, and 4% of the list, respectively. Live donor transplant rates were lowest for type AB candidates (13.4% vs 15.5%, 16.8%, and 15.2%; P < 0.001). On multivariate analysis, type AB candidates had a 1.5-fold greater chance of receiving deceased donor kidney transplants than blood group A candidates (95% CI, 1.45-1.55). Recovery rates of type AB kidneys were similar to those for other blood types, whereas discard rates of type AB kidneys were significantly higher (adjusted OR [aOR], 1.71; 95% CI, 1.56-1.89) for both expanded criteria (aOR, 1.78; 95% CI, 1.52-2.09) and standard criteria donors (aOR, 1.67; 95% CI, 1.48-1.89). LIMITATIONS/CONCLUSIONS:Observational data. Potential confounding from unmeasured covariates. CONCLUSION/CONCLUSIONS:Allocation of type A kidneys to type AB recipients not only increases disparities in waiting times between these 2 groups; but concurrent with the shorter waiting times for type AB candidates, there is suboptimal use of type AB deceased donor and living donor kidneys.

BACKGROUND:Preoperative risk assessment is important yet inexact in older patients because physiologic reserves are difficult to measure. Frailty is thought to estimate physiologic reserves, although its use has not been evaluated in surgical patients. We designed a study to determine if frailty predicts surgical complications and enhances current perioperative risk models. STUDY DESIGN/METHODS:We prospectively measured frailty in 594 patients (age 65 years or older) presenting to a university hospital for elective surgery between July 2005 and July 2006. Frailty was classified using a validated scale (0 to 5) that included weakness, weight loss, exhaustion, low physical activity, and slowed walking speed. Patients scoring 4 to 5 were classified as frail, 2 to 3 were intermediately frail, and 0 to 1 were nonfrail. Main outcomes measures were 30-day surgical complications, length of stay, and discharge disposition. Multiple logistic regression (complications and discharge) and negative binomial regression (length of stay) were done to analyze frailty and postoperative outcomes associations. RESULTS:Preoperative frailty was associated with an increased risk for postoperative complications (intermediately frail: odds ratio [OR] 2.06; 95% CI 1.18-3.60; frail: OR 2.54; 95% CI 1.12-5.77), length of stay (intermediately frail: incidence rate ratio 1.49; 95% CI 1.24-1.80; frail: incidence rate ratio 1.69; 95% CI 1.28-2.23), and discharge to a skilled or assisted-living facility after previously living at home (intermediately frail: OR 3.16; 95% CI 1.0-9.99; frail: OR 20.48; 95% CI 5.54-75.68). Frailty improved predictive power (p < 0.01) of each risk index (ie, American Society of Anesthesiologists, Lee, and Eagle scores). CONCLUSIONS:Frailty independently predicts postoperative complications, length of stay, and discharge to a skilled or assisted-living facility in older surgical patients and enhances conventional risk models. Assessing frailty using a standardized definition can help patients and physicians make more informed decisions.

Nucleic acid testing (NAT) for HIV, HBV and HCV shortens the time between infection and detection by available testing. A group of experts was selected to develop recommendations for the use of NAT in the HIV/HBV/HCV screening of potential organ donors. The rapid turnaround times needed for donor testing and the risk of death while awaiting transplantation make organ donor screening different from screening blood-or tissue donors. In donors with no identified risk factors, there is insufficient evidence to recommend routine NAT, as the benefits of NAT may not outweigh the disadvantages of NAT especially when false-positive results can lead to loss of donor organs. For donors with identified behavioral risk factors, NAT should be considered to reduce the risk of transmission and increase organ utilization. Informed consent balancing the risks of donor-derived infection against the risk of remaining on the waiting list should be obtained at the time of candidate listing and again at the time of organ offer. In conclusion, there is insufficient evidence to recommend universal prospective screening of organ donors for HIV, HCV and HBV using current NAT platforms. Further study of viral screening modalities may reduce disease transmission risk without excessive donor loss.

CONTEXT: More than 6000 healthy US individuals every year undergo nephrectomy for the purposes of live donation; however, safety remains in question because longitudinal outcome studies have occurred at single centers with limited generalizability. OBJECTIVES: To study national trends in live kidney donor selection and outcome, to estimate short-term operative risk in various strata of live donors, and to compare long-term death rates with a matched cohort of nondonors who are as similar to the donor cohort as possible and as free as possible from contraindications to live donation. DESIGN, SETTING, AND PARTICIPANTS: Live donors were drawn from a mandated national registry of 80 347 live kidney donors in the United States between April 1, 1994, and March 31, 2009. Median (interquartile range) follow-up was 6.3 (3.2-9.8) years. A matched cohort was drawn from 9364 participants of the third National Health and Nutrition Examination Survey (NHANES III) after excluding those with contraindications to kidney donation. MAIN OUTCOME MEASURES: Surgical mortality and long-term survival. RESULTS: There were 25 deaths within 90 days of live kidney donation during the study period. Surgical mortality from live kidney donation was 3.1 per 10,000 donors (95% confidence interval [CI], 2.0-4.6) and did not change during the last 15 years despite differences in practice and selection. Surgical mortality was higher in men than in women (5.1 vs 1.7 per 10,000 donors; risk ratio [RR], 3.0; 95% CI, 1.3-6.9; P = .007), in black vs white and Hispanic individuals (7.6 vs 2.6 and 2.0 per 10,000 donors; RR, 3.1; 95% CI, 1.3-7.1; P = .01), and in donors with hypertension vs without hypertension (36.7 vs 1.3 per 10,000 donors; RR, 27.4; 95% CI, 5.0-149.5; P < .001). However, long-term risk of death was no higher for live donors than for age- and comorbidity-matched NHANES III participants for all patients and also stratified by age, sex, and race. CONCLUSION: Among a cohort of live kidney donors compared with a healthy matched cohort, the mortality rate was not significantly increased after a median of 6.3 years.

OBJECTIVE:To review cutting-edge, novel, implemented and potential translational research and to provide a glimpse into rich, innovative, and brilliant approaches to everyday surgical problems. DATA SOURCES/METHODS:Scientific literature and unpublished results. STUDY SELECTION/METHODS:Articles reviewed were chosen based on innovation and application to surgical diseases. DATA EXTRACTION/METHODS:Each section was written by a surgeon familiar with cutting-edge and novel research in their field of expertise and interest. DATA SYNTHESIS/RESULTS:Articles that met criteria were summarized in the manuscript. CONCLUSIONS:Multiple avenues have been used for the discovery of improved means of diagnosis, treatment, and overall management of patients with surgical diseases. These avenues have incorporated the use of genomics, electrical impedence, statistical and mathematical modeling, and immunology.