Ischemic-type biliary lesion post liver-transplantation

A 57-year-old male presented with progressive jaundice, itchiness and dark urine. The patient had a history of liver transplantation 4 months prior due to hepatitis B virus related cirrhosis.

Laboratory tests showed elevated serum levels of total bilirubine, transaminase, alkaline phosphatase and gamma glutamyltransferase.

Magnetic resonance imaging (MRI) was performed using a 3 T scanner before and after the administration of hepatobiliary contrast agent (Gd-EOB-DTPA).

MRI did not visualize on T2-weighted images the main biliary confluence, due to the presence of endoluminal biliary sludge/stones better appreciable on T1-weighted images (Figures 1 and 2). Above the obstruction, a mild dilation of the intrahepatic biliary system was observed, associated with mild periportal edema extending to the right and left portal branches (Figure 3). Two large fluid collections originating from the round liver ligament region were found in the subhepatic space (Figure 4).

One hour after the administration of Gd-EOB-DTPA, a slow and poor excretion was observed, without any biliary leak within the two collections (Figure 5).

The term ischemic-type biliary lesion (ITBL) refers to a non-anastomotic intra- or extra-hepatic biliary stricture post orthotopic liver-transplantation (OLT), without evidence of perfusion restriction (e.g., hepatic artery stenosis) or other causes of biliary damage (e.g., organ rejection) [1].

The reported incidence of ITBL greatly varies between different series, ranging from 1% to 19% [2,3]. The exact pathophysiological mechanism underlying the development of ITBL in liver-recipients is still unknown. However, a multifactorial origin has been suggested, and the three main components were referred to ischemia-related injury, immunologically-mediated injury and cytotoxic-related injury, induced by bile salts [1].

The typical clinical presentation of ITBL is not specific and may include fever, jaundice, dark urine, pale stools itchiness and abdominal pain [4]. Symptomatology usually begins 6 months after OLT. However, many patients are asymptomatic and the first sign of ITBL is the elevation of serum alkaline phosphatase and/or gamma glutamyl transferase [2].

The gold standard for ITBL diagnosis is the direct visualization of bile ducts using invasive techniques such as endoscopic retrograde cholangiopancreatography (ERCP) or percutaneous trans-hepatic cholangiography (PTC) [5]. However, these techniques are not free from various complications (1-7% ERPC, 3.4% PTC) and may also be unsuccessful due to technical challenges [6].

Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive alternative with an excellent diagnostic accuracy in post-OLT biliary obstruction [7].

On MRCP, ITBL appear on T2-weighted images as a lengthy stricture of the main biliary confluence frequently extending to the right and left hepatic ducts [8]. This finding is usually associated with biliary sludge/stones/casts at the level of the stricture hyperintense better appreciable on T1-weighted images. Another characteristic imaging finding of ITBL is represented by wall-thickening of the donor common bile duct.

The administration of hepatobiliary-contrast agents may provide additional functional information, as the time needed for the contrast agent excretion seems to be in correlation with the degree of ITBL [9].

The treatment of ITBL has to be individualized according to the severity and the localization of the stricture [10]. Medical treatment with ursodeoxycholic acid may be administered, but the efficacy of this strategy has never been properly demonstrated [11].

Direct treatment of strictures through dilatation and stenting via endoscopy or percutaneous were successful in 50-70% of patients with ITBL [12]. However, when these techniques fail, surgery may be proposed and when the main biliary confluence is involved, Roux-en-Y hepaticojejunostomy should be considered [12]. If all the previous treatment options were unsuccessful, retransplantation may be unavoidable.

To date, ITBL is associated with a decrease in graft survival, and almost 30% of the patients with ITBL either die or are retransplanted [13].

All patient data have been completely anonymized throughout the entire manuscript and related files.