Martin, John

The benefit of endoscopic retrograde cholangiopancreatography (ERCP) for the treatment of primary sclerosing cholangitis (PSC) remains controversial. To identify predictors of jaundice resolution after ERCP and whether resolution is associated with improved patient outcomes, we conducted a retrospective cohort study of 124 patients with jaundice and PSC. These patients underwent endoscopic biliary balloon dilation and/or stent placement at an American tertiary center, with validation in a separate cohort of 102 patients from European centers. Jaundice resolved after ERCP in 52% of patients. Median follow‐up was 4.8 years. Independent predictors of jaundice resolution included older age (P = 0.048; odds ratio [OR], 1.03 for every 1‐year increase), shorter duration of jaundice (P = 0.059; OR, 0.59 for every 1‐year increase), lower Mayo Risk Score (MRS) (P = 0.025; OR, 0.58 for every 1‐point increase), and extrahepatic location of the most advanced biliary stricture (P = 0.011; OR, 3.13). A logistic regression model predicted jaundice resolution with area under the receiver operator characteristic curve of 0.67 (95% confidence interval, 0.5‐0.79) in the validation set. Independent predictors of death or transplant during follow‐up included higher MRS at the time of ERCP (P < 0.0001; hazard ratio [HR], 2.33 for every 1‐point increase), lower total serum bilirubin before ERCP (P = 0.031; HR, 0.91 for every 1 mg/dL increase), and persistence of jaundice after endoscopic therapy (P = 0.003; HR, 2.30). Conclusion: Resolution of jaundice after endoscopic treatment of biliary strictures is associated with longer transplant‐free survival of patients with PSC. The likelihood of resolution is affected by demographic, hepatic, and biliary variables and can be predicted using noninvasive data. These findings may refine the use of ERCP in patients with jaundice with PSC.

Biliary complications (strictures and leaks) represent major limitations in living donor liver transplantation. Mesenchymal stem cells (MSCs) are a promising modality to prevent biliary complications because of immunosuppressive and angiogenic properties. Our goal was to evaluate the safety of adipose‐derived MSC delivery to biliary anastomoses in a porcine model. Secondary objectives were defining the optimal method of delivery (intraluminal versus extraluminal) and to investigate MSC engraftment, angiogenesis, and fibrosis. Pigs were divided into 3 groups. Animals underwent adipose collection, MSC isolation, and expansion. Two weeks later, animals underwent bile duct transection, reanastomosis, and stent insertion. Group 1 received plastic stents wrapped in unseeded Vicryl mesh. Group 2 received stents wrapped in MSC‐seeded mesh. Group 3 received unwrapped stents with the anastomosis immersed in an MSC suspension. Animals were killed 1 month after stent insertion when cholangiograms and biliary tissue were obtained. Serum was collected for liver biochemistries. Tissue was used for hematoxylin‐eosin and trichrome staining and immunohistochemistry for MSC markers (CD44 and CD34) and for a marker of neoangiogenesis (CD31). There were no intraoperative complications. One pig died on postoperative day 3 due to acute cholangitis. All others recovered without complications. Cholangiography demonstrated no biliary leaks and minimal luminal narrowing. Surviving animals exhibited no symptoms, abnormal liver biochemistries, or clinically significant biliary stricturing. Group 3 showed significantly greater CD44 and CD34 staining, indicating MSC engraftment. Fibrosis was reduced at the anastomotic site in group 3 based on trichrome stain. CD31 staining of group 3 was more pronounced, supporting enhanced neoangiogenesis. In conclusion, adipose‐derived MSCs were safely applied to biliary anastomoses. MSCs were locally engrafted within the bile duct and may have beneficial effects in terms of fibrosis and angiogenesis.