Endoscopic management of post-liver transplant biliary complications

Comparison of time-to-event machine learning models in predicting biliary complication and mortality rate in liver transplant patients

Post-Liver transplantation (LT) survival rates stagnate, with biliary complications (BC) as a major cause of death. We analyzed longitudinal data with a median 19-month follow-up. BC was diagnosed with ultrasounds and MRCP. Missing data was imputed using mean and median. Data preprocessing involved feature scaling and one-hot encoding. Survival analysis used filter (Cox-P, Cox-c) and embedded (RSF, LASSO) feature selection methods. Seven survival machine learning algorithms were used: LASSO, Ridge, RSF, E-NET, GBS, C-GBS, and FS-SVM. Model development employed 5-fold cross-validation, random oversampling, and hyperparameter tuning. Random oversampling addressed data imbalance. Optimal hyperparameters were determined based on average C-index. Features importance was assessed using standardized regression coefficients and permutation importance for top models. Stability was evaluated using 5-fold cross-validation standard deviation. Finally, 1799 observations with 40 outcome predictors were included. RSF with Ridge achieved the highest performance (C-index: 0.699) for BC prediction, while RSF with RSF had the highest performance (C-index: 0.784) for mortality prediction. Top BC predictors were LT graft types, IBD in recipients, recipient's BMI, recipient's history of PVT, and previous LT history. For mortality, they were post-transplant AST, creatinine, recipient's age, post-transplant ALT, and tacrolimus consumption. We identified BC and mortality risk factors, improving decision-making and outcomes.

Comparison of Biliary Complications Between Living and Deceased Donor Liver Transplantations: A Systematic Review and Meta-analysis

To understand if the risk of biliary complications is higher with living donor liver transplantation (LDLT) compared to deceased donor liver transplantation (DDLT), the present meta-analysis was conducted to analyze the differences between these two types of liver transplantations. Three databases were searched from inception to September 2023 for comparative studies reporting biliary complications with LDLT and DDLT. Odds ratios (OR) with 95% confidence intervals were calculated for all the dichotomous outcomes. Twenty-eight studies were included in the final analysis. LDLT was associated with a significantly higher incidence of biliary complications than DDLT (OR 1.96, 95% CI: 1.56-2.47). However, on subgroup analysis, only studies published in or before 2014 reported a higher incidence of biliary complications with LDLT, but not with studies published after 2014. An analysis of individual adverse events showed that LDLT was associated with a higher incidence of both bile leak (OR 3.38, 95% CI: 2.52-4.53) and biliary stricture (OR 1.75, 95% CI: 1.20-2.55). LDLT was associated with a higher incidence of overall biliary complications, including bile leak and biliary stricture. With advances in surgical techniques, there has been a reduction in the risk of biliary complications.

Management of biliary complications in liver transplant recipients using a fully covered self-expandable metal stent with antimigration features

BACKGROUND

Following liver transplant (LT) with duct-to-duct anastomosis, biliary strictures and leaks are typically managed with endoscopic retrograde cholangiopancreatography (ERCP) and stenting. While multiple side-by-side plastic stents are typically used for management of anastomotic strictures, fully covered self-expandable metal stents (FCSEMS) can be used to decrease the number of ERCPs with longer periods of stent patency. The risk of migration can limit their use. FCSEMS with antimigration fins to manage benign biliary complications following LT may provide stricture resolution with limited adverse events (AEs).

METHODS

Single center retrospective study of LT patients who required FCSEMS from 1/2014 to 4/2022. Primary outcomes included stricture resolution and recurrence. Secondary outcomes were stent migration, occlusion, removability, and number of ERCPs.

RESULTS

Forty-three patients (mean age 55.5 years) with anastomotic strictures (N.=37), bile leaks (N.=4) or both (N.=2) were included. The median time from LT to FCSEMS placement was 125 days. Within one year of LT, 31 patients required intervention; early intervention at less than 30 and 90 days was needed in 7 and 19 patients, respectively. The median length of follow-up was 816.5 days. Stricture resolution was seen in 35 patients (81%) after a median stent dwell time of 130.5 days; recurrence occurred in 8 patients. There were three instances of partial stent migration that did not require reintervention or interfere with removability. The mean number of ERCPs required was 2.5.

CONCLUSIONS

The use of a FCSEMS with antimigration features yields effective stricture resolution with longer stent dwell times and fewer ERCPs.

Post-liver transplant biliary complications

Biliary complications (BCs) are the most frequent complications following liver transplantation (LT). They are a major source of morbidity after LT. The incidence of BCs after LT is reported to range from 5% to 45%. The main post-LT biliary complications are strictures, biliary fistulas and bilomas, cholelithiasis, sphincter of Oddi dysfunction, hemobilia, and mucocele. Risk factors for biliary complications are diverse. In this article we seek to review the main types of biliary complications and modern approaches to their diagnosis and treatment.

Innovative Water-Wire Cannulation Technique for Managing Near-Complete Obstruction Due to Post-orthotopic Liver Transplant Anastomotic Strictures: A Report of Two Cases

This report presents an innovative water-wire cannulation technique for managing challenging anastomotic strictures in post-orthotopic liver transplant patients, highlighting its successful application in two distinct cases. Anastomotic strictures pose a significant hurdle in hepatobiliary medicine, often complicating the course post-liver transplantation. Standard endoscopic retrograde cholangiopancreatography (ERCP) methods frequently encounter limitations in severe stricture cases, necessitating alternative approaches. The water-wire cannulation technique, introduced in this report, innovatively utilizes water injection to gently dilate the stricture, enabling successful guidewire insertion and subsequent standard endoscopic interventions. This method was effectively applied in two patients with severe anastomotic strictures, where conventional ERCP techniques were unsuccessful. The technique's effectiveness, demonstrated in these cases, offers a less invasive and potentially safer alternative to traditional options like cholangioscopy, percutaneous transhepatic cholangiography (PTC), or surgical revision, which carry higher risks and complexities. The water-wire cannulation technique's success emphasizes the need for innovative and adaptable strategies in hepatobiliary medicine, especially for managing post-transplant complications. Its potential applicability in a broader spectrum of biliary strictures warrants further exploration. Overall, this technique represents a significant advancement in the endoscopic management of complex biliary strictures, promising to enhance patient care and outcomes in hepatobiliary medicine.

Biliary and Vascular Complications after Liver Transplantation-From Diagnosis to Treatment

The last decades have brought impressive advances in liver transplantation. As a result, there was a notable rise in the number of liver transplants globally. Advances in surgical techniques, immunosuppressive therapies and radiologically guided treatments have led to an improvement in the prognosis of these patients. However, the risk of complications remains significant, and the management of liver transplant patients requires multidisciplinary teams. The most frequent and severe complications are biliary and vascular complications. Compared to vascular complications, biliary complications have higher incidence rates but a better prognosis. The early diagnosis and selection of the optimal treatment are crucial to avoid the loss of the graft and even the death of the patient. The development of minimally invasive techniques prevents surgical reinterventions with their associated risks. Liver retransplantation remains the last therapeutic solution for graft dysfunction, one of the main problems, in this case, being the low number of donors.

Post-transplant biliary complications: advances in pathophysiology, diagnosis, and treatment

Liver transplantation (LT) is the only curative therapy in patients with end-stage liver disease. Long-term survival is excellent, yet LT recipients are at risk of significant complications. Biliary complications are an important source of morbidity after LT, with an estimated incidence of 5%-32%. Post-LT biliary complications include strictures (anastomotic and non-anastomotic), bile leaks, stones, and sphincter of Oddi dysfunction. Prompt recognition and management is critical as these complications are associated with mortality rates up to 20% and retransplantation rates up to 13%. This review aims to summarise our current understanding of risk factors, natural history, diagnostic testing, and treatment options for post-transplant biliary complications.

Post-liver transplant biliary complications: Current knowledge and therapeutic advances

Liver transplantation is the current standard of care for end-stage liver disease and an accepted therapeutic option for acute liver failure and primary liver tumors. Despite the remarkable advances in the surgical techniques and immunosuppressive therapy, the postoperative morbidity and mortality still remain high and the leading causes are biliary complications, which affect up to one quarter of recipients. The most common biliary complications are anastomotic and non-anastomotic biliary strictures, leaks, bile duct stones, sludge and casts. Despite the absence of a recommended treatment algorithm many options are available, such as surgery, percutaneous techniques and interventional endoscopy. In the last few years, endoscopic techniques have widely replaced the more aggressive percutaneous and surgical approaches. Endoscopic retrograde cholangiography is the preferred technique when duct-to-duct anastomosis has been performed. Recently, new devices and techniques have been developed and this has led to a remarkable increase in the success rate of minimally invasive procedures. Understanding the mechanisms of biliary complications helps in their early recognition which is the prerequisite for successful treatment. Aggressive endoscopic therapy is essential for the reduction of morbidity and mortality in these cases. This article focuses on the common post-transplant biliary complications and the available interventional treatment modalities.

Efficacy and safety of device-assisted enteroscopy ERCP in liver transplantation: A systematic review and meta-analysis

BACKGROUND

Enterobiliary anastomoses are the main source of complications after liver transplantation. An endoscopic approach combining device-assisted enteroscopy and ERCP (DAE-ERCP) is technically feasible in postsurgical anatomy.

AIMS

This study aimed at assessing the efficacy, feasibility, and safety of DAE-ERCP in liver-transplanted patients (LT) and other subsets (non-LT).

METHODS

A systematic review and meta-analysis of studies involving DAE procedures in LT patients (between January 2000 and May 2017) was conducted. The main endpoints were as follows: endoscopic, diagnostic, therapeutic, and overall success rates, complications, and the need for surgery.

RESULTS

A total of 155 studies were retrieved, and 6 relevant trials were analyzed. Overall, 132 subjects (72 LT and 60 non-LT) undergoing 257 DAE-ERCP (135 and 122) were included. Complications were rare (4/257), and no deaths occurred. These are the pooled success rates among LT and non-LT patients: 80%-100% and 82%-95% (enteroscopic), 75%-100% and 89%-100% (diagnostic), 67%-100% and 92%-100% (therapeutic), and 60%-100% and 79%-83% (overall results). The requirement for surgery was similar in the two subgroups.

CONCLUSION

In managing biliary complications, the high diagnostic and therapeutic success rates of DAE-ERCP combined with its safety and feasibility encourage its application as a first-line approach to transplanted patients.

Management of Post-Transplant Anastomotic Stricture Using Self-Expandable Metal Stent

Anastomotic stricture (AS) is one of the complications of liver transplantation (LT) and can occur in up to 40% of living-donor LTs. Endoscopic management has become the first-line treatment of AS, and multiple plastic stents insertion has been mainly used in the past. Recently, many treatments utilizing fully covered self-expandable metal stents (cSEMSs) have been attempted, and results showing adequate treatment outcome have been reported. In this review, we look into the treatment performance and cautionary steps needed when using cSEMS as a treatment for AS.

Assessing the utility, findings, and outcomes of percutaneous transhepatic cholangioscopy with SpyglassTM Direct visualization system: a case series

Bile duct stones, indeterminate biliary strictures and other biliary duct pathologies represent a significant surgical and endoscopic challenge in patients with altered luminal or biliary anatomy. Traditional endoscopic retrograde cholangiopancreatography (ERCP) is not feasible and alternative approach is usually required. A novel alternative approach of addressing these challenging cases is assessed by this case series. All patients who underwent percutaneous transhepatic cholangioscopy (PTCS) and Spyglass^TM Direct visualization system (SDVS) between December 2016 and February 2018 were studied. The indications for procedure, interventions performed, outcomes and complications were reviewed for each case. Spyglass^TM marketed by Boston Scientific Corporation, Marlborough, Massachusetts was utilized by interventional endoscopists and radiologists through a 12 French (Fr) percutaneous vascular sheath. Five patients had altered biliary and/or luminal anatomy: two with Roux-en-Y gastric bypass and three with Roux-en-Y hepaticojejunostomy. All patients had unsuccessful previous ERCP attempts. All PTCS with SDVS procedures were technically successful. Indications for this unusual approach were: ascending cholangitis, abnormal liver function tests and biliary dilation on imaging. SDVS was utilized to conduct electrohydraulic lithotripsy (EHL) for biliary stone management in four patients and intraductal biopsies for indeterminate strictures in two of them. PTCS with SDVS can be beneficial for multiple diagnostic and therapeutic indications in patients with altered biliary or luminal anatomy. SDVS allows direct evaluation and management of different biliary pathologies in challenging cases where traditional ERCP is not feasible. Some indications for PTCS with SDVS include evaluation of biliary strictures and biliary stasis, biliary tract biopsy and lithotripsy for management of biliary stones.

Intra-abdominal infections in solid organ transplant recipients: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

This new guideline from the AST IDCOP reviews intra-abdominal infections (IAIs), which cause substantial morbidity and mortality among abdominal SOT recipients. Each transplant type carries unique risks for IAI, though peritonitis occurs in all abdominal transplant recipients. Biliary infections, bilomas, and intra-abdominal and intrahepatic abscesses are common after liver transplantation and are associated with the type of biliary anastomosis, the presence of vascular thrombosis or ischemia, and biliary leaks or strictures. IAIs after kidney transplantation include renal and perinephric abscesses and graft-site candidiasis, which is uncommon but may require allograft nephrectomy. Among pancreas transplant recipients, duodenal anastomotic leaks can have catastrophic consequences, and polymicrobial abscesses can lead to graft loss and death. Intestinal transplant recipients are at the highest risk for sepsis, infection due to multidrug-resistant organisms, and death from IAI, as the transplanted intestine is a contaminated, highly immunological, pathogen-rich organ. Source control and antibiotics are the cornerstone of the management of IAIs. Empiric antimicrobial regimens should be tailored to local susceptibility patterns and pathogens with which the patient is known to be colonized, with subsequent optimization once the results of cultures are reported.

Endoscopic management of biliary strictures post-liver transplantation

Biliary complications play a significant role in morbidity of liver transplant recipients. Biliary strictures occur between 10%-25% of patients with a higher incidence in living donor recipients compared to deceased donors. Strictures can be classified as either anastomotic or non-anastomotic and may be related to ischemic events. Endoscopic management of biliary strictures in the post-transplant setting has become the preferred initial approach due to adequate rates of resolution of anastomotic and non-anastomotic strictures (NAS). However, several factors may increase complexity of the endoscopic approach including surgical anatomy, location, number, and severity of bile duct strictures. Many endoscopic tools are available, however, the approach to management of anastomotic and NAS has not been standardized. Multi-disciplinary techniques may be necessary to achieve optimal outcomes in select patients. We will review the risk factors associated with the development of bile duct strictures in the post-transplant setting along with the efficacy and complications of current endoscopic approaches available for the management of bile duct strictures.

A Review on the Management of Biliary Complications after Orthotopic Liver Transplantation

Orthotopic liver transplantation is the definitive treatment for end-stage liver disease and hepatocellular carcinomas. Biliary complications are the most common complications seen after transplantation, with an incidence of 10-25%. These complications are seen both in deceased donor liver transplant and living donor liver transplant. Endoscopic treatment of biliary complications with endoscopic retrograde cholangiopancreatography (commonly known as ERCP) has become a mainstay in the management post-transplantation. The success rate has reached 80% in an experienced endoscopist's hands. If unsuccessful with ERCP, percutaneous transhepatic cholangiography can be an alternative therapy. Early recognition and treatment has been shown to improve morbidity and mortality in post-liver transplant patients. The focus of this review will be a learned discussion on the types, diagnosis, and treatment of biliary complications post-orthotopic liver transplantation.

Ischemic Cholangiopathy 11 Years after Liver Transplantation from Asymptomatic Chronic Hepatic Artery Thrombosis

Hepatic artery thrombosis is a concerning complication of orthotopic liver transplantation, and it most often occurs early in the posttransplant period. However, on rare occasions it can occur at a time remote from transplant. We present a case of ischemic cholangiopathy complicated by stricture and anastomotic bile leak from chronic hepatic artery thrombosis that occurred 11 years after the transplant. The initial biliary stenting helped with the resolution of the leak but she was found to have stones, sludge and copious pus at the time of stent exchange. Hepatic arteriography demonstrated complete occlusion of the transplant hepatic artery with periportal collaterals reconstituting intrahepatic hepatic arterial branches. The patient was subsequently referred for repeat liver transplantation.

Bleeding after Percutaneous Transhepatic Biliary Drainage: Incidence, Causes and Treatments

Of all procedures in interventional radiology, percutaneous transhepatic biliary drainage (PTBD) is amongst the most technically challenging. Successful placement requires a high level of assorted skills. While this procedure can be life-saving, it can also lead to significant iatrogenic harm, often manifesting as bleeding. Readers of this article will come to understand the pathophysiology and anatomy underlying post-PTBD bleeding, its incidence, its varied clinical manifestations and its initial management. Additionally, a structured approach to its treatment emphasizing endovascular and percutaneous methods is given.

Role of endoscopy in the conservative management of biliary complications after deceased donor liver transplantation

The clinical outcome of patients receiving liver transplantation could be significantly affected by biliary complications, including strictures, leaks, stones and bilomas; early diagnosis and treatment of these conditions lead to markedly reduction in morbidity and mortality. Therapeutic gold standard is represented by conservative approaches, both endoscopic and percutaneous, based on the type of biliary reconstruction, the local availability of the procedures and specific expertise. In patients with previous transplantation, the difficult biliary access and the possible presence of concomitant complications (mainly strictures) further restrict the efficacy of the endoscopic and percutaneous treatments; on the other hand, surgery should generally be avoided because of the even increased morbidity and mortality due to technical and clinical issues. Here we review the most common biliary complications occurring after liver transplantation and discuss available treatment options including future perspectives such as endoscopic ultrasound-guided biliary access in patients with Roux-en-Y choledocho-jejunostomy or extracorporeal shock wave lithotripsy for difficult stones.