Technical Variant Liver Transplant Utilization for Pediatric Recipients: Equal Graft Survival to Whole Liver Transplants and Promotion of Timely Transplantation Only When Performed at High-volume Centers

BACKGROUND

Technical variant liver transplantation (TVLT) is a strategy to mitigate persistent pediatric waitlist mortality in the United States, although its implementation remains stagnant. This study investigated the relationship between TVLT utilization, transplant center volume, and graft survival.

METHODS

Pediatric liver transplant recipients from 2010 to 2020 (n = 5208) were analyzed using the Scientific Registry of Transplant Recipients database. Transplant centers were categorized according to the average number of pediatric liver transplants performed per year (high-volume, ≥5; low-volume, <5). Graft survival rates were compared using Kaplan-Meier curves and log-rank tests. Cox proportional hazards models were used to identify predictors of graft failure.

RESULTS

High-volume centers demonstrated equivalent whole liver transplant and TVLT graft survival ( P = 0.057) and significantly improved TVLT graft survival compared with low-volume centers ( P < 0.001). Transplantation at a low-volume center was significantly associated with graft failure (adjusted hazard ratio, 1.6; 95% confidence interval, 1.14-2.24; P = 0.007 in patients <12 y old and 1.8; 95% confidence interval, 1.13-2.87; P = 0.013 in patients ≥12 y old). A subset of high-volume centers with a significantly higher rate of TVLT use demonstrated a 23% reduction in waitlist mortality.

CONCLUSIONS

Prompt transplantation with increased TVLT utilization at high-volume centers may reduce pediatric waitlist mortality without compromising graft survival.

Preventive Health Screening in Veterans Undergoing Bariatric Surgery

INTRODUCTION

Individuals with obesity are vulnerable to low rates of preventive health screening. Veterans with obesity seeking bariatric surgery are also hypothesized to have gaps in preventive health screening. Evaluation in a multidisciplinary bariatric surgery clinic is a point of interaction with the healthcare system that could facilitate improvements in screening.

METHODS

This is a retrospective cohort study of 381 consecutive patients undergoing bariatric surgery at a Veterans Affairs Hospital from January 2010 to October 2021. Age- and sex-appropriate health screening rates were determined at initial referral to a multidisciplinary bariatric surgery clinic and at the time of surgery. Rates of guideline concordance at both time points were compared using McNemar's test. Univariate and multivariate analyses were performed to identify the risk factors for nonconcordance.

RESULTS

Concordance with all recommended screening was low at initial referral and significantly improved by time of surgery (39.1%‒63.8%; p<0.001). Screening rates significantly improved for HIV (p<0.001), cervical cancer (p=0.03), and colon cancer (p<0.001). Increases in BMI (p=0.005) and the number of indicated screening tests (p=0.029) were associated with reduced odds of concordance at initial referral. Smoking history (p=0.012) and increasing distance to the nearest Veterans Affairs Medical Center (p=0.039) were associated with reduced odds of change from nonconcordance at initial referral to concordance at the time of surgery.

CONCLUSIONS

Rates of preventive health screening in Veterans with obesity are low. A multidisciplinary bariatric surgery clinic is an opportunity to improve preventive health screening in Veterans referred for bariatric surgery.

Eliminating international normalized ratio threshold for transfusion in pediatric patients with acute liver failure

INTRODUCTION

Transfusion protocols are not well-studied for pediatric patients with acute liver failure (ALF). This study evaluates the utility of an international normalized ratio (INR)-based transfusion threshold for these patients.

METHODS

Forty-four ALF pediatric patients from 2009 to 2018 were reviewed and divided into two groups: (a) a threshold group including patients between 2009 and 2015 who were transfused for an INR above 3.0, per institutional policy (n = 30), and (b) a post-threshold group including patients after 2015 through 2018 who were transfused based on clinical judgment (n = 14). Preoperative INRs, preoperative transfusions, intraoperative transfusions, early reoperation, renal function, graft function and deaths were compared.

RESULTS

Liver failure severity was similar between threshold and post-threshold groups. Threshold patients had a lower average INR prior to transplantation, 2.8 (range 1.8-3.8) vs 4.4 (range 2.1-9.0), respectively (P = .01). Twenty-six threshold patients (87%) received preoperative FFP compared with seven post-threshold patients (50%, P = .0088). Two threshold patients (7%) received preoperative cryoprecipitate compared with five post-threshold patients (36%, P = .014). The incidence of pre-transplant bleeding, operative transfusions, and 1-year patient and graft survival did not differ significantly.

CONCLUSION

Clinical judgment vs an INR-based threshold for transfusions did not increase perioperative complications in children with ALF.

Specific patterns of allergic sensitization in early childhood and asthma & rhinitis risk

BACKGROUND

Specific patterns of allergic sensitization as well as quantification of the in vitro IgE response in early life may provide relevant clinical insight into future rhinitis and asthma risk.

OBJECTIVE

To define relationships among established sensitization to particular aeroallergens, quantitative analyses of allergen-specific IgE levels, pet exposure and sensitization, and asthma and rhinitis risk.

METHODS

Children at high-risk for the development of asthma and allergic diseases were enrolled at birth into the Childhood Origins of ASThma (COAST) study. Allergen-specific IgE was assessed at ages 1, 3, 6, and 9 years by fluoroenzyme immunoassay (Unicap(®) 100; Pharmacia Diagnostics). Current asthma and rhinitis were diagnosed at age 6 and 8 years.

RESULTS

Sensitization to dog was strongly associated with increased asthma risk (P < 0.0001). Sensitization to perennial compared with seasonal allergens was more strongly associated with asthma risk, while sensitization to seasonal allergens was more closely associated with rhinitis risk. Increased levels of specific IgE to perennial allergens were associated with an increased asthma risk (P = 0.05), while any detectable level of IgE to seasonal allergens was associated with increased rhinitis risk (P = 0.0009). While dog and cat sensitization were both independently associated with increased asthma and rhinitis risk, dog exposure at birth was associated with a reduced risk of asthma, regardless of dog sensitization status during the first 6 years of life (P = 0.05).

CONCLUSIONS AND CLINICAL RELEVANCE

Analysing specific patterns of an individual's allergic sensitization profile reveals additional relevant associations with asthma and rhinitis risk as opposed to the information gained from characterizing an individual as 'atopic' by the presence of any demonstrable sensitization alone. Furthermore, protective mechanisms of dog exposure with regards to asthma risk appear to be unrelated to the prevention of sensitization.