Bile duct strictures after liver transplantation: A changing landscape of the Achilles' heel

Technical complications lead to significant morbidity and increased mortality during the early postoperative period after liver transplantation. Among the technical complications, vena caval and portal vein stenoses and thromboses occur in 1-2% and 2-3% of the liver recipients, respectively. Diagnostic and treatment algorithms for those problems are well standardized with radiologists being an integral part of the diagnostic and therapeutic armamentarium. Hepatic arterial stenosis and thrombosis, the most common vascular complication after liver transplantation, occurs in about 3-9% of adults and children in the more recent series. The clinical sequela of the biliary ischemia from hepatic arterial stenosis and thrombosis vary from none to multiple bile infarcts, necrosis of the extrahepatic bile duct and bile peritonitis, and multiple and often long strictures in both intra and extrahepatic biliary tree. However, the majority of biliary complications after liver transplantation occur without hepatic arterial stenosis and thrombosis. Biliary complications are considered the Achilles’ heel of liver transplantation because of their frequency and their potential lethal effects on the eventual survival of the graft and patients. With the marked decrease in the routine use of T tubes at the time of transplantation, bile leaks usually occur now at the anastomosis within the first few weeks after transplantation. The second major type of biliary complication, stricture, generally occurs later, and 2 reports in this issue of Liver Transplantation address this topic in adult and pediatric liver recipients. Both series are the largest to date that address the outcomes of bile duct strictures (BDS) in adults and children. The incidence of BDS increases, cumulatively, with the length of follow-up. The median interval after transplantation to the diagnosis of BDS was a year in the report of Sunku et al., but in most reports including the current adult series, an overwhelming majority of BDS occur within the first year after transplantation. Bile duct strictures after liver transplantation are easily and conveniently classified as anastomotic strictures (AS) and nonanastomotic strictures (NAS). The clinical outcomes of the 2 groups are markedly different, rendering the classification extremely useful clinically, as well. Among the etiological factors for the AS technical issues are the most important: improper surgical technique, small caliber of the bile ducts, inappropriate suture material, tension at the anastomosis, and infection. Although the evidence to incriminate ischemia as an important etiological factor in the causation of AS is not as strong as it is in the NAS group, ischemia as an indirect result of the donor conditions probably does play a role. With expertise increasing in the techniques of liver transplantation both worldwide and at individual centers, one would expect a decrease in the incidence of biliary complications over time, especially of AS. The overall incidence of biliary complications after liver transplantation appears to be on the decrease, from the 30% in the pioneering years to about 20% in the 1980s to the current levels of 15%, barring an occasional series with a very low incidence. Whether the incidence of AS would decrease further or remain at the current levels would be answered only with more time. In this regard, it would have been informative had the Austrian study, which spanned 11 years, examined whether the incidence of AS differed in the earlier vs. the later part of the authors’ experience.