Biliary complications after liver transplantation: current perspectives and future strategies

Tacrolimus Monitoring in Liver Transplant Recipients, Posttransplant Cholestasis: A Comparative Between 2 Commercial Immunoassays and a Liquid Chromatography-Tandem Mass Spectrometry Method

BACKGROUND

Cholestasis commonly occurs after orthotopic liver transplantation. It can be extrahepatic because of mechanical obstruction or intrahepatic because of various causes. During cholestasis episodes, blood concentrations of tacrolimus (TAC) metabolites may increase, potentially affecting TAC concentrations measured by immunoassays. This study aimed to simultaneously evaluate the analytical performance of 2 TAC immunoassays, a quantitative microsphere system (QMS) immunoassay, and chemiluminescence microparticle immunoassay, using liquid chromatography-tandem mass spectrometry (LC-MS/MS) as a reference method in liver transplant recipients.

METHODS

This single-center study included 265 patients who underwent orthotopic liver transplantation. In total, 942 blood samples were collected. TAC trough concentrations were measured using LC-MS/MS and 2 immunoassays in parallel. The plasma concentrations of conjugated bilirubin were measured in all samples. The results were analyzed using Bland-Altman plots and Passing-Bablok regressions.

RESULTS

The Bland-Altman plot analysis showed that the TAC QMS immunoassay has a significant bias (+37%) compared with LC-MS/MS, and this bias was higher in patients with cholestasis with hyperbilirubinemia (≤+70% in patients with conjugated bilirubin >150 µmol/L). In comparison, the chemiluminescence microparticle immunoassay showed acceptable analytical performance in patients with hyperbilirubinemia (bias <10%).

CONCLUSIONS

In agreement with previous findings, the TAC QMS immunoassay showed a positive bias compared with LC-MS/MS. This bias is remarkably high in patients with cholestasis and hyperbilirubinemia, suggesting the cross-reactivity of TAC metabolites with the monoclonal antibody used in the QMS immunoassay.

Biliary strictures post pediatric liver transplantation-incidence and risk factors in a single tertiary referral transplant center

BACKGROUND

Biliary strictures are a significant cause of morbidity and graft loss in pediatric liver transplant recipients. Risk factors for the development of biliary strictures are not fully established. We aimed to evaluate the incidence of biliary strictures and treatment modalities outcomes and to identify potential risk factors for occurrence.

METHODS

Pediatric patients who underwent liver transplantation in the single tertiary pediatric liver transplant center in Israel were evaluated. We compared demographics, presentation, laboratory results, imaging, treatment, and outcomes between patients with and without biliary stricture. Multivariate regression analyses were used to identify risk factors for biliary strictures.

RESULTS

Among 121 pediatric liver transplant patients, 65 (53.7%) were males; the median age at the time of liver transplantation was 43 (3-215) months. Fifteen patients (12.4%) had biliary strictures following transplantation. One (7%) patient with biliary stricture was treated via endoscopic retrograde cholangiopancreatography, and 12 patients (80%) underwent interventions via a percutaneous transhepatic approach. Nine of the 12 patients were treated successfully, requiring one or multiple procedures, while the remaining had surgery or laser therapy. Risk factors for the development of biliary strictures were biliary leak, acute cellular rejection, and the presence of two biliary anastomoses.

CONCLUSIONS

In our cohort, the presence of two biliary anastomoses and post-transplant complications including acute cellular rejection and early biliary leaks were associated with biliary strictures in pediatric liver transplantation recipients. Percutaneous transhepatic interventions result in good outcomes in most patients.

Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation

Liver transplantation is a highly complex and challenging field of clinical practice. Although it was originally developed in western countries, it has been further advanced in Asian countries through the use of living donor liver transplantation. This method of transplantation is the only available option in many countries in the Asia-Pacific region due to the lack of deceased organ donation. As a result of this clinical situation, there is a growing need for guidelines that are specific to the Asia-Pacific region. These guidelines provide comprehensive recommendations for evidence-based management throughout the entire process of liver transplantation, covering both deceased and living donor liver transplantation. In addition, the development of these guidelines has been a collaborative effort between medical professionals from various countries in the region. This has allowed for the inclusion of diverse perspectives and experiences, leading to a more comprehensive and effective set of guidelines.

Autologous liver transplantation for unresectable hepatobiliary malignancies in enhanced recovery after surgery model

Ex vivo liver resection combined with autologous liver transplantation offers the opportunity to treat otherwise unresectable hepatobiliary malignancies and has been applied in clinic. The implementation of enhanced recovery after surgery (ERAS) program improves the outcome of surgical procedures. This is a retrospective single-center study including 11 cases of patients with liver cancer that underwent autologous liver transplantation and received ERAS: cholangiocarcinoma of the hilar region (n = 5), intrahepatic cholangiocarcinoma (n = 3), gallbladder cancer (n = 1), liver metastasis from colorectal cancer (n = 1), and liver metastasis from gastrointestinal mesenchymal tumor (n = 1). There were no deaths within 30 days and major complications occurred in two patients, and four patients were readmitted upon the first month after the surgery. Median hospital stay was 20 days (range 13-44) and median open diet was Day 4 (range 2-9) after surgery and median early post-operative activity was Day 5 (range 2-9) after surgery. In conclusion, autologous liver transplantation is feasible in the treatment of otherwise unresectable hepatobiliary malignancies, and our study showed favorable results with autologous liver transplantation in ERAS modality. ERAS modality provides a good option for some patients whose tumors cannot be resected in situ and offers a chance for rapid recovery.

Mechanism and endoscopic-treatment-induced evolution of biliary non-anastomotic stricture after liver transplantation revealed by single-cell RNA sequencing

BACKGROUND

Biliary complications, especially non-anastomotic stricture (NAS), are the main complications after liver transplantation. Insufficient sampling and no recognized animal models obstruct the investigation. Thus, the mechanisms and alterations that occur during endoscopic treatment (ET) of NAS remain unclear.

METHODS

Samples were obtained with endoscopic forceps from the hilar bile ducts of NAS patients receiving continuous biliary stent implantation after diagnosis. Retrospective analysis of multiple studies indicated that the duration of ET for NAS was approximately 1-2 years. Thus, we divided the patients into short-term treatment (STT) and long-term treatment (LTT) groups based on durations of less or more than 1 year. Samples were subjected to single-cell RNA sequencing. Transcriptomic differences between STT and normal groups were defined as the NAS mechanism. Similarly, alterations from STT to LTT groups were regarded as endoscopic-treatment-induced evolution.

RESULTS

In NAS, inflammation and immune-related pathways were upregulated in different cell types, with nonimmune cells showing hypoxia pathway upregulation and immune cells showing ATP metabolism pathway upregulation, indicating heterogeneity. We confirmed a reduction in bile acid metabolism-related SPP1+ epithelial cells in NAS. Increases in proinflammatory and profibrotic fibroblast subclusters indicated fibrotic progression in NAS. Furthermore, immune disorders in NAS were exacerbated by an increase in plasma cells and dysfunction of NK and NKT cells. ET downregulated multicellular immune and inflammatory responses and restored epithelial and endothelial cell proportions.

CONCLUSIONS

This study reveals the pathophysiological and genetic mechanisms and evolution of NAS induced by ET, thereby providing preventive and therapeutic insights into NAS.

HIGHLIGHTS

For the first time, single-cell transcriptome sequencing was performed on the bile ducts of patients with biliary complications. scRNA-seq analysis revealed distinct changes in the proportion and phenotype of multiple cell types during Nonanastomotic stricture (NAS) and endoscopic treatment. A reduction in bile acid metabolism-related SPP1+ epithelial cells and VEGFA+ endothelial cells, along with explosive infiltration of plasma cells and dysfunction of T and NK cells in NAS patients. SPP1+ macrophages and BST2+ T cells might serve as a surrogate marker for predicting endoscopic treatment.

A practical approach to the endoscopic management of biliary strictures after liver transplantation

Biliary tract complications are an important cause of morbidity and mortality after liver transplantation (LT) occurring in 5% to 25% of patients. The most common biliary complication in LT recipients are strictures representing approximately half of these biliary adverse events. Bile duct strictures can be divided into anastomotic biliary strictures (ABS) and non-anastomotic biliary strictures (NABS) depending on their location in the biliary tree, being ABS the most encountered type. Several risk factors identified in previous studies can predispose to the development of ABS and NABS, especially those related to surgical techniques and donor characteristics. Magnetic resonance cholangiopancreatography (MRCP) is the recommended noninvasive imaging test for detecting post-LT biliary strictures, given its high sensitivity and specificity. Once the diagnosis of a biliary stricture after LT has been made, endoscopic retrograde cholangiopancreatography (ERCP) is the preferred initial therapy with good short and long-term results. Biliary sphincterotomy plus balloon dilation (BD) with placement of multiple plastic stents (MPS) has been the classic endoscopic approach for treating ABS, although fully-covered metallic stents (FCSEMS) have emerged as an alternative thanks to shorter total duration of stenting and fewer endoscopic procedures compared to MPS. In this review, we provide a practical update on the management of biliary strictures after LT, focusing our attention on the available evidence in the endoscopic therapy.

Adequate cumulative exposure to tacrolimus and low tacrolimus variability decrease the incidence of biliary complications after liver transplantation

BACKGROUND

Nonearly biliary complications (BCs) after liver transplantation (LT) are highly associated with immunological status. Tacrolimus is the main immunosuppressant. Whether and how tacrolimus bioavailability affects BCs is unclear.

METHODS

LT recipients receiving tacrolimus-free immunosuppressants or developing BCs within 3 months after LT were excluded. Tacrolimus-related variables included trough concentration (C0), variability and cumulative exposure to tacrolimus (CET). Receiver operating characteristic (ROC) curves defined cutoff values of CET and variability. The values divided patients into adequate and low CET groups, also high and low-variability groups. Inverse probability of treatment weighting (IPTW) was used to reduce bias. Logistic regression identified risk factors. Kaplan-Meier curves were generated for survival comparison.

RESULTS

409 patients were enrolled, and 39 (9.5 %) suffered from BCs. The mean C0 values were 6.9 and 7.2 ng/mL in the BCs and BCs-free groups, respectively. CET within 3 postoperative months was 550.0 and 608.6 ng.day/mL, while the tacrolimus variability was 0.4 and 0.3, respectively. The cutoff values for CET within 3 months and variability predicting BCs were 660.5 and 0.54, respectively. Multivariable logistic regression revealed that low CET within 3 months (p = 0.005, p = 0.002) and high variability (p < 0.001, p < 0.001) were associated with BCs before and after IPTW. Appropriate CET and low variability were associated with better overall survival (p = 0.009 and 0.029). Subgroup analysis indicated that long cold ischemia time (CIT), high bilirubin and low CET had a higher relative risk and raised the incidence of BCs.

CONCLUSIONS

Adequate CET and low variability of tacrolimus ameliorated nonearly BCs incidence and improved survival.

Older liver grafts from donation after circulatory death are associated with impaired survival and higher incidence of biliary non-anastomotic stricture

BACKGROUND

Grafts from older donors after circulatory death were associated with inferior outcome in liver transplants in the past. But it has seemed to remain controversial in the last decade, as a result of modified clinical protocols, selected recipients, and advanced technology of organ perfusion and preservation. The present study aimed to examine the impact of older donor age on complications and survival of liver transplant using grafts from donation after circulatory death (DCD).

METHODS

A total of 944 patients who received DCD liver transplantation from 2015 to 2020 were included and divided into two groups: using graft from older donor (aged ≥ 65 years, n = 87) and younger donor (age < 65 years, n = 857). Propensity score matching (PSM) was applied to eliminate selection bias.

RESULTS

A progressively increased proportion of liver transplants with grafts from older donors was observed from 1.68% to 15.44% during the study period. The well-balanced older donor (n = 79) and younger donor (n = 79) were 1:1 matched. There were significantly more episodes of biliary non-anastomotic stricture (NAS) in the older donor group than the younger donor group [15/79 (19.0%) vs. 6/79 (7.6%); P = 0.017]. The difference did not reach statistical significance regarding early allograft dysfunction (EAD) and primary non-function (PNF). Older livers had a trend toward inferior 1-, 2-, 3-year graft and overall survival compared with younger livers, but these differences were not statistically significant (63.1%, 57.6%, 57.6% vs. 76.9%, 70.2%, 67.7%, P = 0.112; 64.4%, 58.6%, 58.6% vs. 76.9%, 72.2%, 72.2%, P = 0.064). The only risk factor for poor survival was ABO incompatible transplant (P = 0.008) in the older donor group. In the subgroup of ABO incompatible cases, it demonstrated a significant difference in the rate of NAS between the older donor group and the younger donor group [6/8 (75.0%) vs. 3/14 (21.4%); P = 0.014].

CONCLUSIONS

Transplants with grafts from older donors (aged ≥ 65 years) after circulatory death are more frequently associated with inferior outcome compared to those from younger donors. Older grafts from DCD are more likely to develop NAS, especially in ABO incompatible cases.

Assessment of a novel biliary-specific near-infrared fluorescent dye (BL-760) for intraoperative detection of bile ducts and biliary leaks during hepatectomy in a preclinical swine model

OBJECTIVES

Postoperative bile leakage is a common complication of hepatobiliary surgery and frequently requires procedural intervention. Bile-label 760 (BL-760), a novel near-infrared dye, has emerged as a promising tool for identifying biliary structures and leakage, owing to its rapid excretion and strong bile specificity. This study aimed to assess the intraoperative detection of biliary leakage using intravenously administered BL-760 compared with intravenous (IV) and intraductal (ID) indocyanine green (ICG).

MATERIALS AND METHODS

Laparotomy and segmental hepatectomy with vascular control were performed on two 25-30 kg pigs. ID ICG, IV ICG, and IV BL-760 were administered separately, followed by an examination of the liver parenchyma, cut liver edge, and extrahepatic bile ducts for areas of leakage. The duration of intra- and extrahepatic fluorescence detection was assessed, and the target-to-background (TBR) of the bile ducts to the liver parenchyma was quantitatively measured.

RESULTS

In Animal 1, after intraoperative BL-760 injection, three areas of leaking bile were identified within 5 min on the cut liver edge with a TBR of 2.5-3.8 that was not apparent to the naked eye. In contrast, after IV ICG administration, the background parenchymal signal and bleeding obscured the areas of bile leakage. A second dose of BL-760 demonstrated the utility of repeated injections, confirming two of the three previously visualized areas of bile leakage and revealing one previously unseen leak. In Animal 2, neither ID ICG nor IV BL-760 injections showed obvious areas of bile leakage. However, fluorescence signals were observed within the superficial intrahepatic bile ducts after both injections.

CONCLUSIONS

BL-760 enables the rapid intraoperative visualization of small biliary structures and leaks, with the benefits of fast excretion, repeatable intravenous administration, and high-fluorescence TBR in the liver parenchyma. Potential applications include the identification of bile flow in the portal plate, biliary leak or duct injury, and postoperative monitoring of drain output. A thorough assessment of the intraoperative biliary anatomy could limit the need for postoperative drain placement, a possible contributor to severe complications and postoperative bile leak.

Biliary complications after liver transplantation: A computed tomography and magnetic resonance imaging pictorial review

Biliary complications are the most common complications after liver transplantation. Computed tomography (CT) and magnetic resonance imaging (MRI) are cornerstones for timely diagnosis of biliary complications after liver transplantation. The diagnosis of these complications by CT and MRI requires expertise, mainly with respect to identifying subtle early signs to avoid missed or incorrect diagnoses. For example, biliary strictures may be misdiagnosed on MRI due to size mismatch of the common ducts of the donor and recipient, postoperative edema, pneumobilia, or susceptibility artifacts caused by surgical clips. Proper and prompt diagnosis of biliary complications after transplantation allows the timely initiation of appropriate management. The aim of this pictorial review is to illustrate various CT and MRI findings related to biliary complications after liver transplantation, based on time of presentation after surgery and frequency of occurrence.

Biliary Complications After Liver Transplantation in the United States: Changing Trends and Economic Implications

BACKGROUND

Biliary complications (BCs) continue to impact patient and graft survival after liver transplant (LT), despite improvements in organ preservation, surgical technique, and posttransplant care. Real-world evidence provides a national estimate of the incidence of BC after LT, implications for patient and graft outcomes, and attributable cost not available in transplant registry data.

METHODS

An administrative health claims-based BC identification algorithm was validated using electronic health records (N = 128) and then applied to nationally linked Medicare and transplant registry claims.

RESULTS

The real-world evidence algorithm identified 97% of BCs in the electronic health record review. Nationally, the incidence of BCs within 1 y of LT appears to have improved from 22.2% in 2002 to 20.8% in 2018. Factors associated with BCs include donor type (living versus deceased), recipient age, diagnosis, prior transplant, donor age, and donor cause of death. BCs increased the risk-adjusted hazard ratio (aHR) for posttransplant death (aHR, 1.43; P < 0.0001) and graft loss (aHR, 1.48; P < 0.0001). Nationally, BCs requiring intervention increased risk-adjusted first-year Medicare spending by $39 710 (P < 0.0001).

CONCLUSIONS

BCs remain an important cause of morbidity and expense after LT and would benefit from a systematic quality-improvement program.

Impact of different ischemia times on biliary stricture after living donor liver transplantation with biliary atresia

Biliary atresia (BA) is the most common indication for pediatric liver transplantation, and biliary stricture (BS) remains an Achilles' heel for pediatric living donor liver transplantation (LDLT). We investigated the impact of different ischemia times on BS after LDLT in patients with BA. We retrospectively analyzed patients (<18 y) with BA who underwent LDLT between January 2016 and December 2020. Cases with hepatic artery thrombosis, bile leakage, early BS (<2 wk), and early death (<3 mo) were excluded. In all, 572 cases were included. A total of 26 cases (4.55%, 26/572) developed BS: 25 patients with anastomotic stricture and 1 patient with anastomotic stricture combined with left hepatic duct stricture. In addition, the time to diagnosis of BS ranged from 1.8 to 53.0 months (mean, 13.0 mo and median, 8.2 mo) after transplantation. A multivariate logistic regression analysis showed that arterial ischemia time (AIT), per 10 minutes (OR=1.222, 95% CI: 1.007-1.438, p =0.04) was the only independent risk factor for the development of BS after LDLT in patients with BA. What is more, the 5-year cumulative risk of BS between the AIT ≥40 minutes and AIT <40 minutes groups was 2.79% versus 10.57%. AIT was the only independent risk factor for the development of BS after LDLT with BA, and AIT ≥40 minutes would increase the 5-year cumulative risk of BS in our study. A shorter AIT, especially AIT <40 minutes, should be kept to decrease BS.

Gastroduodenal artery disconnection during liver transplantation decreases non-anastomotic stricture incidence

BACKGROUND

The hepatic artery is the only blood source nourishing the biliary duct and associated with biliary complication after liver transplantation (LT). Gastroduodenal artery (GDA) disconnection increased proper hepatic artery flow. Whether this procedure attenuates biliary non-anastomotic stricture (NAS) is not clear.

METHODS

A total of 241 patients with LT were retrospectively analyzed. The patients were divided into the GDA disconnection (GDA-) and GDA preservation (GDA+) groups. Propensity score matching (PSM) was administrated to reduce bias. Logistic regression was conducted to analyze risk factors for biliary NAS before and after PSM. Postoperative complications were compared. Kaplan-Meier survival analysis and log-rank tests were performed to compare overall survival.

RESULTS

In all, 99 patients (41.1%) underwent GDA disconnection, and 49 (20.3%) developed NAS. Multivariate logistic regression revealed that GDA preservation (OR = 2.24, 95% CI: 1.11-4.53; P = 0.025) and model for end-stage liver disease (MELD) score > 15 (OR = 2.14, 95% CI: 1.12-4.11; P = 0.022) were risk factors for biliary NAS. PSM provided 66 pairs using 1:2 matching method, including 66 GDA disconnection and 99 GDA preservation patients. Multivariate logistic regression after PSM also showed that GDA preservation (OR = 3.15, 95% CI: 1.26-7.89; P = 0.014) and MELD score > 15 (OR = 2.41, 95% CI: 1.08-5.36; P = 0.031) were risk factors for NAS. When comparing complications between the two groups, GDA preservation was associated with a higher incidence of biliary NAS before and after PSM (P = 0.031 and 0.017, respectively). In contrast, other complications including early allograft dysfunction (P = 0.620), small-for-size graft syndrome (P = 0.441), abdominal hemorrhage (P = 1.000), major complications (Clavien-Dindo grade ≥ 3, P = 0.318), and overall survival (P = 0.088) were not significantly different between the two groups.

CONCLUSIONS

GDA disconnection during LT ameliorates biliary NAS incidence and may be recommended for application in clinical practice.

Liver Transplantation in Recipients With a Positive Crossmatch: A Retrospective Single-Center Match-Pair Analysis

A positive crossmatch (XM+) is considered a contraindication to solid abdominal organ transplantation except liver transplantation (LT). Conflicting reports exist regarding the effects of XM+ on post-transplant outcomes. The goal of this retrospective single-center analysis is to evaluate the influence of XM+ on relevant outcome parameters such as survival, graft rejection, biliary and arterial complications. Forty-nine adult patients undergoing LT with a XM+ between 2002 and 2017 were included. XM+ LT recipients were matched 1:2 with crossmatch negative (XM-) LT recipients based on the balance of risk (BAR) score. Patient and graft survival were compared using Kaplan-Meier survival analysis and the log-rank test. Comparative analysis of clinical outcomes in XM+ and XM- groups were conducted. Patient and graft survival were similar in XM+ and XM- patients. Rejection episodes did not differ either. Recipients with a strong XM+ were more likely to develop a PCR+ CMV infection. A XM+ was not associated with a higher incidence of biliary or arterial complications. Donor age, cold ischemia time, PCR+ CMV infection and a rejection episode were associated with the occurrence of ischemic type biliary lesions. A XM+ has no effects on patient and graft survival or other relevant outcome parameters following LT.

Graft aberrant hepatic arteries in deceased donor liver transplantation: The "one liver, one artery" approach

In liver transplantation (LT), graft aberrant hepatic arteries (aHAs) frequently require complex arterial reconstructions, potentially increasing the risk of post-operative complications. However, intrahepatic hilar arterial shunts are physiologically present and may allow selective aHA ligation. Thus, we performed a retrospective study from a single-center cohort of 618 deceased donor LTs where a selective reconstruction policy of aHAs was prospectively applied. In the presence of any aHA, the vessel with the largest caliber was first reconstructed. In case of adequate bilobar arterial perfusion assessed on intraparenchymal Doppler ultrasound, the remnant vessel was ligated; otherwise, it was reconstructed. Consequently, outcomes of three patient groups were compared: the "no aHAs" group (n = 499), the "reconstructed aHA" group (n = 25), and the "ligated aHA" group (n = 94). Primary endpoint was rate of biliary complications. Only 38.4% of right aHAs and 3.1% of left aHAs were reconstructed. Rates of biliary complications in the no aHA, reconstructed aHA, and ligated aHA groups were 23.4%, 28%, and 20.2% (p = 0.667), respectively. The prevalence rates of primary non-function (p = 0.534), early allograft dysfunction (p = 0.832), and arterial complications (p = 0.271), as well as patient survival (p = 0.266) were comparable among the three groups. Retransplantation rates were 3.8%, 4%, and 5.3% (p = 0.685), respectively. In conclusion, a selective reconstruction policy of aHAs based on Doppler assessment of bilobar intraparenchymal arterial flow did not increase post-operative morbidity and avoided unnecessary and complex arterial reconstructions.

Utility of Digital Single-operator Video Cholangioscopy for the Endoscopic Management of Biliary Complications After Liver Transplantation-A Single-center Experience

BACKGROUND

Liver transplant recipients (LTRs) frequently develop biliary complications, and endoscopy is crucial for their subsequent management. Recently, single-operator video cholangioscopy (SOVC) with digital imaging quality was introduced. This study evaluated the utility of digital SOVC for the management of biliary complications in LTRs.

METHODS

This observational study retrospectively analyzed all LTRs undergoing digital SOVC between 2015 and 2019 at a tertiary referral center. Endpoints included the assessment of biliary strictures, performance of selective guidewire passage across biliary strictures, and diagnosis and treatment of biliary stone disease.

RESULTS

In total, 79 digital SOVCs performed in 50 LTRs were identified. Fifty-eight percent of the procedures were performed for biliary stricture assessment, and using visual signs or guided biopsies, SOVC excluded malignancy in all cases (100%). Of all the examinations, 29.1% (23/79) were performed solely because of a previous failure of conventional endoscopic methods to pass a guidewire across a biliary stricture. Using SOVC, guidewire passage was successfully performed in 73.9% of these examinations, enabling subsequent endoscopic therapy. Furthermore, biliary stones were found in 16.5% (13/79) of the examinations. In 38.5% of these cases, standard fluoroscopy failed to detect stones, which were only visualized using digital SOVC. Biliary stone treatment was successful in 92% (12/13) of the examinations. Complications occurred in 11.4% of all SOVCs. No procedure-associated mortalities were observed.

CONCLUSIONS

Digital SOVC is effective and safe for the endoscopic management of biliary complications in LTRs and offers unique diagnostic and therapeutic opportunities that strongly impact the clinical course in selected cases.

Risk factors and management of biliary stones after living donor liver transplant and its effect on graft outcome

Background

Bile stones are associated with numerous complications in liver transplant recipients. Endoscopic retrograde cholangiopancreatography (ERCP) has been proven to be safe and highly effective in dealing with most post-transplant biliary complications.

Objective

The objective of this study was to identify the possible risk factors for bile stone formation on top of biliary stricture, the effects of stones on graft outcomes, and their management.

Methods

This case–control study included 83 patients who underwent living donor liver transplant (LDLT) and suffered from postoperative biliary stricture with or without stones. Patients were divided into two groups. Group 1 (n = 55) included patients with biliary strictures with no stones and group 2 (n = 28) included patients who developed stones on top of biliary strictures. Data about the recipient and donor characteristics, surgical technique, blood lipid profile, immunosuppressive drugs, post-transplant complications, and interventions were collected from the medical records.

Results

The frequency of hepatitis C virus (HCV) was significantly higher in group 2 compared to group 1 (71.4% vs. 47.3%, p = 0.036). The body mass index (BMI) of the donors was significantly higher in group 2 than in group 1 (25.17 ± 2.53 vs. 23.68 ± 2.63, p = 0.015). Episodes of acute rejection were significantly higher in group 2 than in group 1 (21.4% vs. 5.5%, p = 0.027). The ERCP was sufficient in most of the cases (89.2%) to ensure biliary drainage. The identified independent risk factors for biliary stones included HCV, biliary drain, donor's BMI, and serum cholesterol level.

Conclusion

Positive HCV, biliary drain insertion, donor's BMI, and serum cholesterol level were independent risk factors for developing bile stones on top of biliary strictures. Biliary stones were associated with high episodes of acute graft rejection, and they could be successfully managed by the ERCP modality.

The use of the T-tube in biliary tract reconstruction during orthotopic liver transplantation: An umbrella review

Biliary complications are one of the main concerns after liver transplantation, and to avoid these, the use of a T-tube has been advocated in biliary reconstruction. Most liver transplantation centres perform a biliary anastomosis without a T-tube to avoid the risk of complications and T-tube-related costs. Several meta-analyses have reached discordant conclusions regarding the benefits of using the T-tube. An umbrella review was performed to summarise quantitative measures about overall biliary complications, biliary leaks, biliary strictures and cholangitis associated with the T-tube use after liver transplantation. Published systematic reviews and meta-analyses related to the use of T-Tube in liver transplantation were searched and analysed. From the comprehensive literature search from PubMed, EMBASE and Cochrane Library databases on the 25th of October 2021, 104 records were retrieved. Seven meta-analyses and two systematic reviews were included in the final analysis. All the meta-analyses of RCT stated no differences in overall biliary complications and biliary leaks when using T-tube for a liver transplant (I² ≥ 90% and I² range 0-76%, respectively). The meta-analysis of the RCTs evaluating the risks of biliary strictures after liver transplantation showed that T-tube protects from the complication (I² range 0-80%). Biliary anastomosis without a T-tube has equivalent overall biliary complications and bile leaks compared to the T-tube reconstruction. The incidence of biliary strictures is attenuated in patients with T-tubes, and most meta-analyses of RCTs have very low heterogeneity. Therefore, the present umbrella review suggests a selective T-tube use, particularly in small biliary ducts or transplants with marginal grafts at high risk of post-LT strictures.

Post-Transplantation Cytomegalovirus Infection Interplays With the Development of Anastomotic Biliary Strictures After Liver Transplantation

Background: Anastomotic biliary stricture (ABS) remains the most frequent complication after liver transplantation (LT). This study aimed to identify new anastomotic biliary stricture risk factors, with a specific focus on postoperative events. Additionally, ABS management and impact on patient and graft survival were assessed.

Methods: All consecutive patients who underwent LT with duct-to-duct anastomosis between 2010 and 2019 were included. All patients who died within 90 days after LT due to non-ABS-related causes were excluded.

Results: Among 240 patients, 65 (27.1%) developed ABS after a median time of 142 days (range, 13–1265). Median follow-up was 49 months (7–126). Upon multivariable analysis, donor BMI (OR=0.509, p = 0.037), post-LT CMV primoinfection (OR = 5.244, p &lt; 0.001) or reactivation (OR = 2.421, p = 0.015) and the occurrence of post-LT anastomotic biliary fistula (OR = 2.691, p = 0.021) were associated with ABS. Anastomotic technical difficulty did not independently impact the risk of ABS (OR = 1.923, p = 0.051). First-line ABS treatment was systematically endoscopic (100%), and required a median of 2 (range, 1–11) procedures per patient. Repeat LT was not required in patients developing ABS. The occurrence of ABS was not associated with overall patient survival (p = 0.912) nor graft survival (p = 0.521).

Conclusion: The risk of developing ABS after LT seems driven by the occurrence of postoperative events such as CMV infection and anastomotic fistula. In this regard, the role of CMV prophylaxis warrants further investigations.

Percutaneous Transhepatic Radiologic Intervention of Biliary Complications following Liver Transplantation: A Single-center Experience

Background

Biliary complications are the leading cause of morbidity and mortality in patients undergo¬ing Liver Transplantation (LT). Post-biliary transplantation strictures (BSs) are a severe problem with a high risk of graft failure. However, management of these BSs has remained controversial, and consid¬erable variability has been reported in Percutaneous Transhepatic Radiological Interventions (PTRIs) related to broad differences in technical procedures.

Objective

This study aimed to evaluate the efficacy of percutaneous treatments in managing post-LT BSs in a center in Shiraz.

Methods

PTRIs including balloon dilatation, metallic stent, and internal or internal-external hand-made plastic stent insertion were done for 34 transplanted patients with BSs referring to the Interventional Radiology Unit of Shiraz Namazi Hospital. Technical success rate, patency rates, and complications were evaluated.

Results

The. In this study, 31 strictures were successfully treated without any significant difference between the anastomotic and non-anastomotic types of stricture (success rate: 91.2%). Based on the results, 12- , 24-, and 36-month primary patency rates were 90.1%, 84.5%, and 76.8%, respectively. The secondary patency rate was 100% at 12 and 24 months and 93.3% at 36 and 60 months. The rate of minor complica¬tions (mild cholangitis and hemobilia) was 6.4%, and no major complications were detected.

Conclusion

According to the findings, PTRI is an effective method for treating anastomotic and non-anas- tomotic strictures with a high success rate and low complications.