Biliary complications after transplantation in children: role of imaging modalities

Portal Venous Flow Alterations in Hepatic Artery Thrombosis Following Liver Transplant

OBJECTIVES

The hepatic vasculature is a unique system due to a dual supply that includes the hepatic artery and portal vein, which interact when the liver vascular supply is decreased. Hepatic artery buffer response, an intrinsic regulatory mechanism that compensates for blood supply, maintains increased hepatic artery flow and caliber in response to portal vein failure. Previous studies revealed that portal vein flow showed no alterations to establish adequate blood supply in response to hepatic artery occlusion. Here, we analyzed portal vein flow changes in patients with hepatic artery thrombosis after liver transplant.

MATERIALS AND METHODS

From December 1988 to October 2017, our center performed 580 liver transplant procedures. Those diagnosed with hepatic artery thrombosis (19 females, 24 males) by Doppler ultrasonography during postoperative week 1 were analyzed. Patients received either surgery or endovascular treatment for hepatic artery thrombosis, with patency confirmed by Doppler ultrasonography. We compared portal vein flow velocity and caliber before and after treatment using Wilcoxon signed rank and Mann Whitney U tests.

RESULTS

Mean patient age was 18.9 ± 21.4 years. Portal vein flow velocity pretreatment (median of 70 cm/ s) was significantly higher than posttreatment (median of 52 cm/ s) in all patients (P < .001). Median flow velocity decreased significantly after treatment when subgroups were compared, including age (adult vs child), transplant type (orthotopic transplant vs living donor), and treatment (surgery vs endovascular). However, portal vein flow velocity showed a significantly higher decrease in the surgery subgroup than in the endovascular treatment subgroup (P = .018). There was no significant relationship between portal vein calibers before and after treatment (P = .36).

CONCLUSIONS

The significant decrease in portal vein flow velocity after successful treatment of hepatic artery thrombosis may represent a compensatory flow change of the portal vein in response to diminished hepatic artery flow.

Hepatobiliary scintigraphy for the assessment of biliary strictures after pediatric liver transplantation

HBS is used in the management of liver transplantation, a significant complication of which is biliary stricture. Strictures may be intraparenchymal within segments and main duct (non-anastomotic) or at the biliary-enteric anastomosis (anastomotic). Strictures are definitively diagnosed, and often managed, by PTC. This is invasive, technically challenging, and requires general anesthesia in young children. HBS may allow early detection of these complications and is non-invasive. The aim of this study was to review the scintigraphic pattern of biliary strictures using (99m)TcDISIDA HBS following pediatric orthotopic liver transplantation, and to assess its role in the diagnostic algorithm of suspected biliary strictures. All available hepatobiliary studies performed post-transplant in 101 episodes of liver transplantation in 92 pediatric patients were reviewed. Twenty-three (23%) patients had known biliary strictures. Twenty-two patients had adequate studies available for review; five had intrahepatic (non-anastomotic) strictures alone, nine had a stricture of the anastomosis alone, and eight had both intrahepatic and anastomotic strictures. HBS patterns (either segmental or global changes) correlated very highly with clinically significant biliary strictures. All patients with known strictures had abnormal HBS; hence, in patients with abnormal liver function tests post-liver transplant, a normal HBS makes strictures very unlikely. We propose that HBS can thus be used to determine if further investigation is required.

Diagnosis and interventional radiological treatment of vascular and biliary complications after liver transplantation in children with biliary atresia

OBJECTIVE

Early diagnosis and appropriate management of vascular and biliary complications after living donor liver transplantation (LDLT) result in longer survival. We report our institutional experience regarding radiological management of these complications among patients with biliary atresia (BA) who underwent LDLT.

METHODS

We analyzed the records of 116 children. All patients underwent Doppler ultrasound (US) at operation, daily for the first 2 postoperative weeks, and when necessary thereafter. After primary evaluation using US, the definite diagnosis of postoperative complication was confirmed using computed tomography, magnetic resonance imaging, and/or operation.

RESULTS

There were 61 boys and 55 girls. The overall mean age was 2.69 years. The overall mean preoperative weight and height were 13.06 kg and 83.79 cm, respectively. There were 28 (24.13%) biliary and vascular complications. These were cases of biliary stricture (n = 5), bile leakage (n = 3), hepatic artery stenosis (n = 6), hepatic vein stenosis (n = 4), and portal vein thrombosis (n = 17). The diagnostic accuracy of US in detecting biliary complication, hepatic artery stenosis, hepatic venous stenosis, and portal vein thrombosis was 95.69%, 97.41%, 100%, and 100%, respectively. US in combination with multiple imaging modalities and clinical suspicion resulted in 100% diagnostic accuracy. Percutaneous transhepatic cholangiography, thrombolysis, balloon angioplasty, and stent placement were performed for the complications noted. There was an early mortality due to multiple-organ failure after failed radiological invention and subsequent surgical management.

CONCLUSIONS

Doppler US is accurate in detecting postoperative complications after pediatric LDLT for BA. Radiological interventions for vascular and biliary complications are effective and safe alternatives to reconstructive surgery.

Cystic duct remnant mucocele in a liver transplant recipient

Cystic duct remnant mucocele is an extremely rare complication of liver transplantation in children. Surgical correction is usually required for cystic duct remnant mucocele when it causes biliary obstruction. We describe a 14-month-old liver transplant recipient who presented with biliary obstruction 1 month after orthotopic liver transplantation with an end-to-end choledochocholedocal biliary anastomosis for hepatoblastoma. US, CT and cholangiography findings were consistent with mucocele of the allograft cystic duct remnant. Surgery was not needed in our patient because the mucocele and biliary obstruction had resolved on repeat imaging most likely due to guidewire manipulation during cholangiography, resulting in opening of the cystic duct remnant orifice and drainage into the common duct.

Surgical complications and outcome of pediatric liver transplantation in Hong Kong

PURPOSE

The aim of this study was to analyze the early and late results of pediatric liver transplantation, with particular reference to complications that required surgical or radiologic intervention.

METHODS

The records and code sheets of children who underwent liver transplantation in the authors' institution between September 1993 and December 2001 were reviewed.

RESULTS

Twenty-nine children (16 boys and 13 girls) underwent 31 liver transplantations (23 living donor, 8 cadaveric donor) during the study period. The ages of the children ranged from 4 months to 132 months (median, 16 months). Eighteen children had complications that required surgical or radiologic interventional procedures. Complications included, among others, hepatic vein thrombosis (n = 1, 3%), hepatic vein stenosis (n = 2, 7%), portal vein thrombosis (n = 2, 7%), biliary stricture (n = 3, 10%), bile leakage (n = 2, 7%), hepatic artery pseudoaneurysm (n = 1, 3%), jejuno-jejunostomy leakage (n = 1, 3%), graft hepatitis (n = 1, 3%), and posttransplant lymphoproliferative disorder (n = 2, 7%). In addition, 6 children (21%) suffered from intraabdominal bleeding from a variety of causes. After appropriate interventions, at a median follow-up of 38 months (range, 1 to 96 months), patient and graft survival rates were 79% and 74%, respectively. The retransplantation rate was only 7%. There was no incidence of hepatic artery thrombosis. All living donors remain alive and well.

CONCLUSIONS

Complications are inevitable in pediatric liver transplantation. However, with timely recognition and active intervention, a good outcome can be achieved.

Imaging of biliary complications following paediatric liver transplantation

Biliary complications (BC) are well recognised following paediatric liver transplantation. We reviewed retrospectively 169 consecutive liver transplants performed in 139 children. BC occurred in 36/169 grafts (21 %) in 35/139 patients (25 %). Biliary obstruction was present in 18/169 grafts (11 %), biliary leakage in 14/169 grafts (8 %) and a combination of obstruction and leakage was present in 4/169 (2 %) grafts. BC were as likely to present radiologically as they were with either clinical and/or biochemical abnormalities. Most BC (26/36, i. e. 72 %) occurred in the first 2 weeks following transplantation. Ultrasound and cholangiography were the principle imaging modalities used for detection of these complications. False negative ultrasound examinations occurred in three patients with biliary obstruction and in three patients with biliary leakage. False negative cholangiograms occurred in two patients with biliary leakage. Ultrasound is important in the post-operative surveillance of paediatric liver transplants, with cholangiography having a complementary role in those with BC.

Diagnostic and therapeutic endoscopic retrograde cholangiography after liver transplantation

BACKGROUND

We report our current experience using endoscopic retrograde cholangiography in the management of post-transplantation biliary tract complications.

METHODS

Twenty-three patients among 109 adult liver transplant recipients underwent retrograde cholangiography because of cholestasis (18 patients) or bile leaks (5 patients).

RESULTS

Eleven of 18 patients developed anastomotic strictures, all successfully dilated by plastic stents; one patient required Roux-en-Y revision due to recurrent cholangitis while stented. Three had biliary calculi extracted following sphincterotomy. Two developed intrahepatic ductal strictures secondary to severe rejection. One patient had hepatic artery thrombosis with a hilar stricture. One cholangiogram was normal. Three patients developed bile peritonitis following T-tube removal, all treated by sphincterotomy and nasobiliary drainage. Choledochal perforation resulting from an impacted T-tube limb was detected in two patients, both treated with sphincterotomy and nasobiliary drainage.

CONCLUSIONS

Strictures within 3 months of surgery required 3 months of stenting; those occurring later required longer periods of time to respond. Bile leaks responded uniformly and rapidly to drainage. Endoscopic retrograde cholangiography is a useful diagnostic and therapeutic intervention for post-transplantation biliary tract complications.

Biliary complications after paediatric liver transplantation: Birmingham's experience

Between 1983 and 1992, 112 children underwent liver transplantation. Of 138 grafts, 60 (43.4%) were whole livers, 77 (55.6%) were reduced livers, and 1 (0.7%) was a split liver. Biliary complications (BC) were defined as any abnormality, even minor, related to the biliary tract. Results were analysed with a minimum follow-up of 9 months. Some 36 grafts (26.1%) in 34 patients (30.4%) presented with BC: bile leaks (17 grafts), biliary obstructions or dilatations (16 grafts), and other complications (3 grafts). Management was mainly surgical with biliary reconstruction via a Roux-en-Y loop. Interventional radiology had an increasing role in recent years. BC were associated with a mortality of 1.8% (2/112), a graft loss rate of 4.3% (6/138), and significant morbidity. Among the various factors whose association with BC was studied, the date of transplantation, the use of reduced grafts and the use of gallbladder conduits appeared to be the main determining factors for BC. From multivariate analysis the use of reduced grafts emerged as the most important factor in reducing BC. We therefore conclude that BC are associated with significant morbidity, but general improvements in both surgical and medical management seem to account for better results in recent years.

Ultrasound-guided pediatric liver transplant biopsy using a spring-propelled cutting needle (biopsy gun)

Biopsy is the best way to diagnose allograft rejection, the most common complication following liver transplantation. The authors reviewed 99 consecutive ultrasound-guided cutting needle biopsies in 19 infants and children. Conscious sedation was used with 95 biopsies. General anesthesia was used with four biopsies, all in patients undergoing percutaneous biliary procedures at the same time. Ninety-eight biopsies were diagnostic. Only one major complication occurred: biloma. Ultrasound-guided cutting needle biopsy of pediatric liver transplant patients can be performed safely and efficaciously.

Biliary tract complications in pediatric orthotopic liver transplantation

Biliary tract complications are reported in 15% to 30% of orthotopic liver transplantations (OLTs). Since 1986, 53 OLTs were done in 48 children with a mean age and weight of 5.3 years and 18.9 kg, respectively. Twenty-seven transplantations (51%) were reduced liver grafts (RLG) and 26 (49%) were whole liver grafts (WLG). Since 1988, 70% of transplantations have been RLG. Choledochocholedochostomy (mean weight, 25 kg) with a T-tube (CC) or choledochojejunostomy (CJ) (mean weight, 14.5 kg) were done in 24 (45%) and 29 (55%) cases, respectively. The overall mortality was 19% but none of the deaths were related to biliary problems. There were 13 biliary tract complications (24.5%) in 11 patients including 7 leaks, 5 obstructions, and 1 intrahepatic biloma. Leaks leading to bile peritonitis were managed with simple suture and drainage and were related to the T-tube (4), to the Roux-en-Y loop (2), and to the transection margin of a RLG (1). Obstruction was documented in 5 cases with none associated with hepatic artery thrombosis (HAT). Stenosis after CC reconstruction (2) required conversion to CJ. Two patients had revision of CJ because of kinking of the common bile duct after a left lateral segment graft and an anastomotic stricture 46 months after OLT. The last patient developed a vanishing bile duct syndrome 4 months posttransplant and is awaiting retransplantation. One patient had multiple episodes of cholangitis after HAT and was retransplanted. Neither the type of grafts (RLG 25.9% v WLG 23.1%) nor the type of biliary reconstruction (CC 25% v CJ 24%) influenced the rate of biliary complications.(ABSTRACT TRUNCATED AT 250 WORDS)