Pediatric liver transplantation: fourteen years of experience at the children institute in São Paulo, Brazil

Microsurgical arterial anastomosis in young and adult rats: an evolutive and comparative study

Purpose:

To evaluate the caliber of an arterial micro-anastomosis in the young growing animal using a continuous suture technique. Additionally, late morphological changes and blood flows distal to the anastomosis were evaluated.

Methods:

Seventy-four Wistar rats were submitted to laparotomy to access the aorta for blood flow measurement. The aorta was sectioned using microsurgery technique and an end-to-end anastomosis with continuous suture. After a period of six months to one year, the anastomosis was checked.

Results:

Regarding the size of the aortas, comparing the pre- and postoperative values, there was an increase of 13.33% in adult animals and 25% in young animals, without any difference in the blood flows.

Conclusions:

The arteries of young rats show signs of growth at the site of the anastomosis performed with continuous suture.

Vascular Complications in Pediatric Liver Transplants and Their Management

OBJECTIVES

The blood supply of the liver occurs through the hepatic artery and portal vein. Outflow of blood circulation in the liver is via the hepatic veins. Any disruption in this blood circulation results in deterioration of liver functions. In this study, we evaluated early vascular complications in pediatric liver transplant recipients seen at our center.

MATERIALS AND METHODS

From November 1988 to December 2021, our team has performed 701 liver transplant procedures, which have included 334 pediatric liver transplants. Among these pediatric liver transplant recipients (mean age of 7.34 y), 176 were male patients. Nineteen patients (5.7%) were recipients of deceased donors. Reason for liver failure was mainly biliary atresia (n = 169). Mean weight of recipients was 23.3 kg. Most graft types were left lateral grafts (n = 204).

RESULTS

Three patients had hepatic vein complications. All 3 patients were successfully treated with interventional radiological methods by placing a stent in the anastomosis region. Portal vein complications occurred in 3 patients. One patient had hemostasis performed surgically. The second patient had surgically revision of the anastomosis because of thrombus formation. Because of stenosis of more than 50% in the portal vein anastomosis, the third patient required stent placement in the anastomosis region. Hepatic artery complications occurred in 54 patients: 31 patients had hepatic artery thrombosis, 13 patients had hepatic artery stenosis, 7 patients had bleeding from hepatic artery anastomosis, 2 patients had hepatic artery dissection, and 1 patient had pseudoaneurysm in the hepatic artery. Forty-three of these patients were successfully treated with interventional radiological methods and 11 required surgical treatment.

CONCLUSIONS

Vascular complications after liver transplant can cause deterioration in hepatic functions and acute liver failure. Vascular complications can be successfully treated in experienced organ transplant centers.

Percutaneous transhepatic interventional therapy of portal vein stenosis in paediatric liver transplantation: A systematic review of efficacy and safety

PURPOSE OF THE SYSTEMATIC REVIEW

To determine the efficacy and safety of percutaneous trans-hepatic balloon and/or stent angioplasty (PTA) in the management of portal vein (PV) stenosis following paediatric liver transplantation.

METHODS

Articles were included from a systematic search of Medline, Embase, Cochrane CENTRAL, ClinicalTrials.gov and International Clinical Trials Registry from inception to the 29th of August 2020.

RESULTS

There were 213 paediatric liver recipients who underwent PTA for PV stenosis in 19 included studies published between 1991 and 2019. Balloon angioplasty was the initial treatment in the majority (n = 153). Primary stent placement (n = 34) was performed for elastic recoil, intimal tears and PV kinks and rescue stent placement (n = 14) for recurrent PV stenosis following primary balloon angioplasty. The technical success was 97.6%-100% overall, 97.6%-100% for balloon-angioplasty-only and 100% for primary stenting. The clinical success was 50%-100% overall, 50%-100% for balloon-angioplasty-only and 100% for primary stenting. Long-term PV patency was 50%-100% overall, 37.5%-100% for balloon-angioplasty-only and 100% for primary stenting. Primary balloon angioplasty was successful in 78% of the cases. Of the recurrent PV stenoses, 9% resolved with stent placement and one required a meso-Rex shunt. There was one re-transplantation without stenting. The complication rate was 2.6% for balloon-angioplasty-only (bleeding, liver abscess, 2 PV thromboses) and 5.9% for primary stenting (bleeding, stent-fracture). There was no procedure-related mortality.

CONCLUSION

Percutaneous transhepatic balloon angioplasty may be the initial management of portal vein stenosis in paediatric liver recipients. Stent placement may be a primary option in selected cases and a reliable rescue option for recurrent portal vein stenosis following balloon-angioplasty-only.

Portal vein obstruction after pediatric liver transplantation: A systematic review of current treatment strategies

INTRODUCTION

Portal vein obstruction (PVO) is a significant vascular complication after liver transplantation (LT) in pediatric patients. Current treatment strategies include percutaneous transluminal angioplasty (PTA), with or without stent placement, mesorex bypass (MRB), splenorenal shunt, mesocaval shunt, endovascular recanalization (EVR), splenic artery embolization and splenectomy. However, specific characteristics of patients undergoing intervention and selection of individual treatment and its efficacy have remained unclear. This review systematically analyzed biochemical and clinical characteristics, selection of treatment, efficacy, and post-procedural complications.

METHODS

We systematically searched PubMed and Embase between January 1995 and March 2021 for studies on the management of PVO after LT. We analyzed the reports for biochemical and clinical characteristics at the timing of the intervention in different patients, selection of treatment, and reported efficacies.

RESULTS

We found 22 cohort studies with 362 patients who had the following characteristics: biliary atresia (83%), living-donor LT (85%), thrombocytopenia (73%), splenomegaly (40%), ascites (16%), or gastrointestinal bleeding (26%). The 3-year primary patency of PTA without stent placement was similar to that with stent placement (70%-80% and 43%-94%, respectively). MRB was used as an initial treatment with a 3-year patency of 75% to 100%. One study showed that 5-year primary patency of EVR was 80%. Secondary patency was 90% to 100% after 3 years in all studies with PTA alone, PTA/stent placement, and stent placement alone.

CONCLUSION

This is the first review of all treatment protocols in PVO after pediatric LT. We showed that an important group of patients has severe symptoms of portal hypertension. Efficacy of all treatment modalities was high in the included studies which make them important modalities for these patients.

Therapeutic effect of portal vein stenting for portal vein stenosis after upper-abdominal surgery

BACKGROUND

The therapeutic effect of portal vein (PV) stenting for PV stenosis following nontransplant hepato-pancreato-biliary (HPB) surgery has not been fully investigated.

METHODS

Changes in portal venous pressure (PVP) gradient before and after stenting, complications, symptomatic improvement, and stent patency were evaluated.

RESULTS

We identified 14 consecutive patients undergoing PV stenting for malignant (n = 8) and benign (n = 6) PV stenosis. Signs of PV stenosis were composed of refractory ascites in 6 patients, varices with hemorrhagic tendencies in 5, and abnormal liver function in 5. The median PVP gradient after PV stenting was 3.0 cm H₂O (range, 1.5-3.0), which was significantly smaller than that before PV stenting (median, 15 cm H₂O [range, 2.5-25]; P < 0.01). Thirteen out of 14 (93%) achieved clinical success with symptomatic improvement, except one patient with sustained refractory ascites because of peritoneal seeding. During the median follow-up time of 7.3 months (range, 1.0-87), stent occlusion occurred in two patients (14%) because of intrastent tumor growth. The 1-year cumulative stent patency rate was 76% in the entire cohort.

CONCLUSIONS

Based on durable effect on patency, we deemed PV stenting for PV stenosis after HPB surgery to be safe and beneficial for improving symptoms.

Antithrombotic management and thrombosis rates in children post-liver transplantation: A case series and literature review

Thrombosis is a major postoperative complication in pediatric liver transplantation. There is marked heterogeneity in prophylactic antithrombotic therapies used, without established guidelines. This review summarizes current worldwide incidence of thrombotic events and compares antithrombotic therapies in children post-liver transplant, with comparison to our institution's experience. Of the twenty-three articles with sufficient detail to compare antithrombotic regimens, the overall incidence of thrombosis ranged from 2.4% to 17.3%. Incidence of HAT ranged from 0% to 28.1%, of HVT from 0% to 4.7%, of PVT from 1.5% to 11.2%, and of IVC thrombosis from 0% to 2.8%. Re-transplantation due to thrombosis ranged from 0% to 4.8%. Prophylactic antithrombotic therapies varied between studies, and bleeding complications were infrequently reported. Since 2010, 96 children underwent 100 liver transplants at our institution with thrombosis incidence comparable to international literature (HAT 6%, PVT 5%, IVC 1%, and HVT 0%). Re-transplantation due to thrombosis occurred in 2% and major bleeding occurred in 10%. The prophylactic antithrombotic therapies used post-liver transplantation in children remain varied. Low rates of thrombosis have been reported with antiplatelet use both with and without anticoagulation. Standard definitions and consistent reporting of bleeding complications are required, in addition to thrombosis rates, so that true risk-benefit assessment of reported regimes can be understood.

Living Donor Liver Transplantation in Biliary Atresia Children with Pulmonary Hypertension

OBJECTIVE

Though living donor liver transplantation (LDLT) is commonly performed for pediatric patients with biliary atresia (BA), pulmonary hypertension (PH) is seldom encountered or reported previously. The aim of this study is mainly to identify the prevalence of PH in pediatric patients undergoing liver transplantation and assess whether PH significantly augment the operative risk and evaluate the outcomes in this series of patients.

DESIGN

Retrospectively cohort study.

SETTING

Renji hospital, Shanghai, China.

PARTICIPANTS

This study comprised 161 pediatric patients undergoing LDLT.

INTERVENTIONS

Patient diagnosed of PH in preoperative examination was compared to those without PH in intra- or post- operative complications or outcomes.

MEASUREMENTS AND MAIN RESULTS

We collected clinical records of LDLT surgery for pediatric patients during the year of 2016 in our hospital. Results suggested that pediatric patients undergoing LDLT had a substantial number of PH with a prevalence of 16.1% in this study. No significant difference was identified between two groups of patients regarding intraoperative outcomes and postoperative complications and mortality.

CONCLUSION

LDLT is a safe procedure in a selected group of BA patients with PH, however, further long-term clinical investigations and mechanical researches are needed.

Current management of biliary atresia based on 35 years of experience at a single center

OBJECTIVE

The prognosis of patients with biliary atresia undergoing Kasai portoenterostomy is related to the timing of the diagnosis and the indication for the procedure. The purpose of the present study is to present a practical flowchart based on 257 children who underwent Kasai portoenterostomy.

METHODS

We conducted a retrospective cohort study of patients who underwent Kasai portoenterostomy between 1981 and 2016.

RESULTS

During the first period (1981 to 2009), 230 infants were treated, and the median age at the time of surgery was 84 days; jaundice was resolved in 77 patients (33.5%). During the second period, from 2010 to 2016, a new diagnostic approach was adopted to shorten the wait time for portoenterostomy; an ultrasonography examination suggestive of the disease was followed by primary surgical exploration of the biliary tract without complementary examination or liver biopsy. Once the diagnosis of biliary atresia was confirmed, a portoenterostomy was performed during the same surgery. During this period, 27 infants underwent operations; the median age at the time of surgery was 66 days (p<0.001), and jaundice was resolved in 15 patients (55.6% - p=0.021), with a survival rate of the native liver of 66.7%.

CONCLUSION

Primary surgical exploration of the biliary tract without previous biopsy was effective at improving the prognostic indicators of patients with biliary atresia undergoing Kasai portoenterostomy.

Single Center Long-Term Results of Pediatric Liver Transplantation

OBJECTIVES

Liver replacement continues to be the only definitive mode of therapy for children with end-stage liver disease. However, it remains challenging because of the rare donor organs, complex surgical demands, and the necessity to prevent long-term complications. Our objectives were to analyze 16 years of experience in the Shiraz University Organ Transplant Center.

MATERIALS AND METHODS

We retrospectively analyzed the records of 752 patients (< 18 years old) who underwent orthotopic liver transplant at our center over a 16-year period. Mean age was 90 months, and male-to-female ratio was 1.25. Of the 752 transplants, 354 were whole organs, 311 were from living related donors, and 87 were in situ split liver allografts. Patient and graft survival rates were determined at 1, 3, and 5 years, and results between groups were compared.

RESULTS

Overall mortality was 31.8%. The 1-, 3-, and 5-year patient survival rates were 77%, 69%, and 66%, respectively, whereas the respective graft survival rates were 75%, 68%, and 65%. We observed significant differences in survival according to graft type (log-rank test, P < .001). We also observed significant differences in survival probabilities according to age (log-rank test, P < .001). Cox regression was used to simultaneously analyze effects of age and graft type on survival. Both graft type and age significantly affected survival (P < .001). The 1-, 3, and 5-year survival rates for patients having whole organ transplants were 88%, 81%, and 78%. Patients who received living donor grafts had respective survival rates of 66%, 60%, and 58%, with rates of 65%, 47%, and 47% for patients who received split grafts.

CONCLUSIONS

Our results were similar to those observed in the literature in terms of indication for transplant and posttransplant survival.

Portal Vein Stenting for Delayed Jejunal Varix Bleeding Associated with Portal Venous Occlusion after Hepatobiliary and Pancreatic Surgery

Objective

The study aimed to describe portal stenting for postoperative portal occlusion with delayed (≥ 3 months) variceal bleeding in the afferent jejunal loop.

Materials and Methods

Eleven consecutive patients (age range, 2–79 years; eight men and three women) who underwent portal stenting between April 2009 and December 2015 were included in the study. Preoperative medical history and the postoperative clinical course were reviewed. Characteristics of portal occlusion and details of procedures were also investigated. Technical success, treatment efficacy (defined as disappearance of jejunal varix on follow-up CT), and clinical success were analyzed. Primary stent patency rate was plotted using the Kaplan-Meier method.

Results

All patients underwent hepatobiliary-pancreatic cancer surgery except two children with liver transplantation for biliary atresia. Portal occlusion was caused by benign postoperative change (n = 6) and local tumor recurrence (n = 5). Variceal bleeding occurred at 27 months (4 to 72 months) and portal stenting was performed at 37 months (4 to 121 months), on average, postoperatively. Technical success, treatment efficacy, and clinical success rates were 90.9, 100, and 81.8%, respectively. The primary patency rate of portal stent was 88.9% during the mean follow-up period of 9 months. Neither procedure-related complication nor mortality occurred.

Conclusion

Interventional portal stenting is an effective treatment for delayed jejunal variceal bleeding due to portal occlusion after hepatobiliary-pancreatic surgery.

Amlodipine-induced gingival overgrowth in a child after liver transplant

Drug-induced gingival overgrowth (GO) has been associated with phenytoin, cyclosporine, and calcium channel blocker therapies. This study reports the case of an 11-year-old girl who was referred for evaluation of GO, which had occurred over the last 6 months. Her medical history included a liver transplant due to biliary atresia 3 years ago, immunosuppressive therapy, and hypertension, which is why she was started on a daily intake of amlodipine. The intraoral examination showed generalized GO, and the treatment consisted of a gingivectomy. Subsequently, amlodipine was replaced with captopril and oral hygiene instructions. There was no recurrence of GO after 28 months of follow-up. Although GO may be related to the chronic use of amlodipine, such an association is uncommon in pediatrics, and the treatment consists of the replacement of medication combined with a surgical approach and plaque control.

Early type I collagen deposition is associated with prognosis in biliary atresia

BACKGROUND

Biliary atresia (BA) is a cholestatic liver disease of children that progresses to hepatic fibrosis. BA is the main indication of pediatric liver transplantation (LTx). Histopathological markers in liver biopsies could be useful for predicting progression to end-stage disease.

OBJECTIVE

To establish histopathological or immunohistochemical markers in liver biopsies of BA patients and correlate those markers with prognosis.

METHOD

Histological analysis of biliary alterations and morphometric assessment of liver fibrosis were performed, in addition to indirect immunofluorescence assays (IF) for type I, III, IV and V collagens in initial and final liver biopsies of 36 patients with BA who underwent Kasai hepatoportoenterostomy (KPE) and LTx in the last 20years at a single center.

RESULTS

Histopathological markers had no correlation with evolutive time until LTx. The perisinusoidal deposition of type III and V collagens was more prominent in the initial biopsies (p<0.01), whereas deposition of type I and IV collagens indicated progression (p<0.01). Patients with large amounts of perisinusoidal type I collagen in the initial biopsies had worse progression time curves until LTx (p=0.04).

CONCLUSION

Morphometric assessment of perisinusoidal deposition of type I collagen by IF in the initial biopsy can correlate with progression time to LTx in post-surgical BA.

Dynamic expression of desmin, α-SMA and TGF-β1 during hepatic fibrogenesis induced by selective bile duct ligation in young rats

We previously described a selective bile duct ligation model to elucidate the process of hepatic fibrogenesis in children with biliary atresia or intrahepatic biliary stenosis. Using this model, we identified changes in the expression of alpha smooth muscle actin (α-SMA) both in the obstructed parenchyma and in the hepatic parenchyma adjacent to the obstruction. However, the expression profiles of desmin and TGF-β1, molecules known to be involved in hepatic fibrogenesis, were unchanged when analyzed by semiquantitative polymerase chain reaction (RT-PCR). Thus, the molecular mechanisms involved in the modulation of liver fibrosis in this experimental model are not fully understood. This study aimed to evaluate the molecular changes in an experimental model of selective bile duct ligation and to compare the gene expression changes observed in RT-PCR and in real-time quantitative PCR (qRT‐PCR). Twenty-eight Wistar rats of both sexes and weaning age (21-23 days old) were used. The rats were separated into groups that were assessed 7 or 60 days after selective biliary duct ligation. The expression of desmin, α-SMA and TGF-β1 was examined in tissue from hepatic parenchyma with biliary obstruction (BO) and in hepatic parenchyma without biliary obstruction (WBO), using RT-PCR and qRT‐PCR. The results obtained in this study using these two methods were significantly different. The BO parenchyma had a more severe fibrogenic reaction, with increased α-SMA and TGF-β1 expression after 7 days. The WBO parenchyma presented a later, fibrotic response, with increased desmin expression 7 days after surgery and increased α-SMA 60 days after surgery. The qRT‐PCR technique was more sensitive to expression changes than the semiquantitative method.

Postoperative care in pediatric liver transplantation

In the last 25 years, liver transplantation in children has become an effective, definitive, and universally accepted treatment for terminal liver diseases. Long-term survival exceeds 80% and improves each year as the result of constant technical advancements and improvements in immediate postoperative intensive care and clinical control.

Stent placement versus angioplasty for hepatic artery stenosis after liver transplant: a meta-analysis of case series

BACKGROUND

Hepatic artery stenosis (HAS) is a serious complication of liver transplantation but data on the most effective endovascular management are lacking. We aimed to compare percutaneous balloon angioplasty (PBA) with stent placement.

METHODS

We searched MEDLINE, Cochrane, Web of Science, EMBASE, SCOPUS, and Biosis Previews between 1970 and December 2011 and performed meta-analysis of short-term (procedural success, complications) and long-term outcomes (liver function, arterial patency, survival, re-intervention, re-transplantation). Random effects models were used for the analysis and meta-regression performed for the year of study.

RESULTS

A total of 263 liver transplants in 257 patients [age 43 (±8) years] underwent 147 PBAs and 116 stents. Transplanted livers were from deceased donors in 240 (91 %). Follow-up was 1 month to 4.5 years (median 17 months). PBA and stent had similar procedural success (89 % vs. 98 %), complications (16 % vs. 19 %), normal liver function tests (80 % vs. 68 %), arterial patency (76 % vs. 68 %), survival (80 % vs. 82 %), and requirement for re-intervention (22 % vs. 25 %) or re-transplantation (20 % vs. 24 %) (P non-significant). In the most recent studies re-transplantation was reported less compared to older series (P = 0.04).

CONCLUSION

Both PBA and stent offer comparable results for HAS. These techniques have contributed to a recent decline in re-transplantation.

KEY POINTS

• Interventional radiological procedures are often used to treat post-transplant hepatic artery stenosis. • Meta-analysis shows that percutaneous balloon angioplasty and stent placement are both efficacious. • Percutaneous balloon angioplasty and stent placement appear to have similar complication rates. • Re-transplantation rates have declined, partly due to interventional management for arterial stenosis.

Centrilobular necrosis as a manifestation of venous outflow block in pediatric malnourished liver transplant recipients--case reports

CLN is a frequent histological finding in biopsies after pediatric: LT, and its pathogenesis has not yet been fully clarified and has different causes. Among the vascular causes, VOB is sometimes difficult to diagnose, especially when technical variants such as split-liver, reduced-liver, or living-related LT are utilized. Three liver-transplanted malnourished children (ages 12, 20, and 28 months) developed altered LFTs and post-operative ascites with right pleural effusion (two cases) and jaundice (one case). Doppler ultrasound examinations were normal and liver biopsies showed CLN interpreted as severe ACR. There were no responses to the medical treatment. Additional investigation with CT angiography suggested obstructed hepatic vein drainage, which was confirmed by interventional radiology and angioplasty of the anastomosis between the hepatic vein and the inferior vena cava, with clinical and histological resolution. It is concluded that in malnourished children undergoing LT with technical variations, in which the occurrence of severe ACR is usually less common because of the severity of the patient condition, the finding of CLN should raise the possibility of VOB, so that excessive immunosuppression and its consequences can be avoided.

Long-term results of the percutaneous transhepatic venoplasty of portal vein stenoses after pediatric liver transplantation

  This paper has the objective to evaluate retrospectively the long-term results of transhepatic treatment of PV stenoses after pediatric LT. During an eight-yr period, 15 children with PV stenoses underwent PTA with balloon dilation or stent placement in case of PTA failure after LT. Patients' body weights ranged from 9.3 to 46kg (mean, 15.5kg). PV patency was evaluated in the balloon dilation and in the stent placement groups. Technical and clinical successes were achieved in all cases with no complication. Eleven patients (11/15; 73.3%) were successfully treated by single balloon dilation. Four patients (4/15; 26.7%) needed stent placement. One patient was submitted to stent placement during the same procedure because of PTA failure. The other three developed clinical signs of portal hypertension because of PV restenoses two, eight, and twenty-eight months after the first PTA. They had to be submitted to a new procedure with stent placement. The follow-up time ranged from 3 to 8.1 yr (mean, 6.3 yr). In conclusion, transhepatic treatment of PV stenoses after pediatric LT with balloon dilation or stent placement demonstrated to be a safe and effective treatment that results in long-term patency.

Which is the best technique for hepatic venous reconstruction in pediatric living-donor liver transplantation? Experience from a single center

BACKGROUND/PURPOSE

The introduction of the piggyback technique for reconstruction of the liver outflow in reduced-size liver transplants for pediatric patients has increased the incidence of hepatic venous outflow block (HVOB). Here, we proposed a new technique for hepatic venous reconstruction in pediatric living-donor liver transplantation.

METHODS

Three techniques were used: direct anastomosis of the orifice of the donor hepatic veins and the orifice of the recipient hepatic veins (group 1); triangular anastomosis after creating a wide triangular orifice in the recipient inferior vena cava at the confluence of all the hepatic veins (group 2); and a new technique, which is a wide longitudinal anastomosis performed at the anterior wall of the inferior vena cava (group 3).

RESULTS

In groups 1 and 2, the incidences of HVOB were 27.7% and 5.7%, respectively. In group 3, no patient presented HVOB (P = .001). No difference was noted between groups 2 and 3.

CONCLUSIONS

Hepatic venous reconstruction in pediatric living-donor liver transplantation must be preferentially performed by using a wide longitudinal incision at the anterior wall of the recipient inferior vena cava. As an alternative technique, triangulation of the recipient inferior vena cava, including the orifices of the 3 hepatic veins, may be used.

Hepatic artery reconstruction in pediatric living donor liver transplantation under 10 kg, without microscope use

Arterial reconstructions are pivotal, particularly in pediatric LDLT. We describe microsurgical reconstruction technique with 6x loupes and the clinical course of the first 23 less than 10 kg recipients in an initial LDLT program at a developing country. From March 2002 to October 2008, 286 liver transplantation were performed in 279 patients at our unit. There were 73 children and 206 adults. Among the children, 23 weighing less than 10 kg were recipients from living donors. Arterial reconstructions were with end-to-end interrupted suture using a 6x magnification loupe, according to the untied suture technique. All patients were prospectively followed by color Doppler ultrasound protocol. In our initial experience there were no arterial complications. With mean 24 months of follow-up, 19 patients (82%) are alive with good graft function. Hepatic artery in LDLT can be safely reconstructed with microsurgical techniques without microscope using, with 6x loupe magnification, and can achieve good results in patients under 10 kg.

Surgical treatment of hepatic tumors in children: lessons learned from liver transplantation

PURPOSE

Hepatectomy remains a complex operation even in experienced hands. The objective of the present study was to describe our experience in liver resections, in the light of liver transplantation, emphasizing the indications for surgery, surgical techniques, complications, and results.

METHODS

The medical records of 53 children who underwent liver resection for primary or metastatic hepatic tumors were reviewed. Ultrasonography, computed tomographic (CT) scan, and needle biopsy were the initial methods used to diagnose malignant tumors. After neoadjuvant chemotherapy, tumor resectability was evaluated by another CT scan. Surgery was performed by surgeons competent in liver transplantation. As in liver living donor operation, vascular anomalies were investigated. The main arterial anomalies found were the right hepatic artery emerging from the superior mesenteric artery and left hepatic artery from left gastric artery. Hilar structures were dissected very close to liver parenchyma. The hepatic artery and portal vein were dissected and ligated near their entrance to the liver parenchyma to avoid damaging the hilar vessels of the other lobe. During dissection of the suprahepatic veins, the venous infusion was decreased to reduce central venous pressure and potential bleeding from hepatic veins and the vena cava.

RESULTS

Fifty-three children with hepatic tumors underwent surgical treatment, 47 patients underwent liver resections, and in 6 cases, liver transplantation was performed because the tumor was considered unresectable. There were 31 cases of hepatoblastoma, with a 9.6% mortality rate. Ten children presented with other malignant tumors-3 undifferentiated sarcomas, 2 hepatocellular carcinomas, 2 fibrolamellar hepatocellular carcinomas, a rhabdomyosarcoma, an immature ovarian teratoma, and a single neuroblastoma. These cases had a 50% mortality rate. Six children had benign tumors-4 mesenchymal hamartoma, 1 focal nodular hyperplasia, and a mucinous cystadenoma. All of these children had a favorable outcome. Hepatic resections included 22 right lobectomies, 9 right trisegmentectomies, 8 left lobectomies, 5 left trisegmentectomies, 2 left segmentectomies, and 1 case of monosegment (segment IV) resection. The overall mortality rate was 14.9%, and all deaths were related to recurrence of malignant disease. The mortality rate of hepatoblastoma patients was less than other malignant tumors (P = .04).

CONCLUSION

The resection of hepatic tumors in children requires expertise in pediatric surgical practice, and many lessons learned from liver transplantation can be applied to hepatectomies. The present series showed no mortality directly related to the surgery and a low complication rate.

Ursodeoxycholic acid in neonatal hepatitis and infantile paucity of intrahepatic bile ducts: review of a historical cohort

We retrospectively reviewed the role of ursodeoxycholic acid in infants having nonsurgical cholestasis attending the Hepatology Clinic, New Children Hospital, Cairo University, Egypt, from 1985 until 2005. Files of 496 infants with neonatal hepatitis and 97 with intrahepatic bile duct paucity were included; of them 241 (48.6%) and 52 (46.4%) received 20-40 mg/kg/day ursodeoxycholic acid for 319.2 +/- 506.9 days and 480.3 +/- 583.3 days, respectively. The outcome of infants with neonatal hepatitis with intake of ursodeoxycholic acid and those without was: 108 (44.8%) and 179 (70.2%) successful (P = 0.000), 11 (4.6%) and 13 (5.1%) improved (P = 0. 474), 112 (46.5%) and 61 (23.9%) suffered failed outcome (P = 0.000), and 10 (4.1%) and 2 (0.78%) died (P = 0.014), respectively. Likelihood of successful outcome with ursodeoxycholic acid intake was 0.345 (P = 0.000), and that of deterioration was 2.76 (P = 0.000). For those having intrahepatic bile duct paucity likelihood of successful outcome with ursodeoxycholic acid intake was 0.418 (P = 0.040) and that of deterioration was 2.64 (P = 0.028). Ursodeoxycholic acid failed in management of this cohort of infants with nonsurgical cholestasis.

Selection of live-related liver transplantation candidates

PURPOSE

Living donor liver transplantation (LR) is an important alternative for children. We compared our outcomes of LR and cadaveric (CAD) graft recipients, with attention to the pediatric end-stage liver disease (PELD) score and perioperative morbidity and mortality to identify appropriate candidates for LR.

METHODS

Our transplant database and electronic medical records were searched for demographics and outcome measures.

RESULTS

From 2000 to 2008, 81 children underwent liver transplantation from 37 LR and 44 CAD donors. There were no significant differences in graft or overall survival at 3 months or 1 year. The LR group was significantly younger (4.46 +/- 5.2 years vs 7.41 +/- 6.6 years; P = .03) and had a significantly lower PELD score (12.7 +/- 13 vs 22 +/- 12; P = .001) at the time of transplantation. Ten patients were transplanted for unresectable tumor in the LR group vs 4 CAD (P = .03). Significantly fewer LR recipients required return to the operating room in the first 30 days posttransplant (13.9% vs 34.1%; P = .03). The LR recipients had a higher rate of biliary stricture requiring reoperation (22.2% vs 2.3%; P = .005).

CONCLUSIONS

The LR liver transplantation is highly selected for patients with a parent donor who will need transplant but do not yet have a high PELD score. A lower PELD score at operation may have contributed to the lower incidence of postoperative complications requiring reoperation.

Registry of Hospital das Clínicas of the University of São Paulo Medical School: first official solid organ and tissue transplantation report - 2008

OBJECTIVE

The aim of this study was to report a single center experience of organ and tissue transplantation

INTRODUCTION

This is the first report of organ and tissue transplantation at the Hospital das Clínicas of the University of Sao Paulo Medical School.

METHODS

We collected data from each type of organ transplantation from 2002 to 2007. The data collected were patient characteristics and actuarial survival Kaplan-Meier curves at 30 days, one year, and five years

RESULTS

There were a total of 3,321 transplants at our institution and the 5-year survival curve ranged from 53% to 88%.

CONCLUSION

This report shows that solid organ and tissue transplants are feasible within the institution and allow us to expect that the quality of transplantation will improve in the future.

Review of historical cohort: ursodeoxycholic acid in extrahepatic biliary atresia

BACKGROUND

Ursodeoxycholic acid is a bile acid that was found to increase bile flow, protect hepatocytes, and dissolve gallstones.

PURPOSE

The objective of this study is to review ursodeoxycholic acid in infants and children with extrahepatic biliary atresia.

METHODS

We used a statistical analysis of data of records of infants and children having extrahepatic biliary atresia who underwent Kasai portoenterostomy and attended Hepatology Clinic, New Children's Hospital, Cairo University, Egypt, from May 1985 until June 2005.

RESULTS

Of 141 infants with extrahepatic biliary atresia, 108 received ursodeoxycholic acid for mean duration +/- SD of 252.6 +/- 544.9 days in a dosage of 20 mg/kg per day. The outcome of infants who did not receive ursodeoxycholic acid and those who did was the following: 8 (24.2%) and 11 (10.18%) had a successful outcome (P = .043), 0 (0%) and 7 (6.4%) improved (P = .148), 25 (75.7%) and 84 (77.7%) had a failed outcome (P = .489), and none vs 5 died (4.6%) (P = .135), respectively. The predictors of successful outcomes were age less than 65 days at portoenterostomy (P = .008) and absence of ursodeoxycholic acid intake (P = .04) with a likelihood of a successful outcome that was 2.8, that associated with ursodeoxycholic acid intake.

CONCLUSION

In this cohort of infants with extrahepatic biliary atresia, ursodeoxycholic acid was not shown to be effective, and its use was associated with a plethora of hepatic and extrahepatic complications.

Effect of the immunosuppressants on hepatocyte proliferation and apoptosis in a young animal model of liver regeneration: an immunohistochemical study using tissue microarrays

Hepatocyte proliferation and apoptosis (programmed cell death) occur during the liver parenchyma regeneration and the liver size modeling is mainly controlled by hepatocyte apoptosis. The purpose of the present study was to verify the influence of immunosuppressant drugs on these phenomena by utilizing tissue microarray techniques. Thirty-six weaning rats (age 21-23 days, weight 30-50 g) were divided into six groups: control, sham, hepatectomy, hepatectomy plus solumedrol, hepatectomy plus CsA, and hepatectomy plus Tac. The animals were killed one day after hepatectomy, and the remnant livers were weighed and harvested for tissue microarray sections. Liver cell proliferation was evaluated by staining for PCNA and apoptosis was detected by the TUNEL method. It was verified that CsA promoted a decrease in the liver weight, Tac and CsA decreased the proliferation index of hepatocytes, and glucocorticoid had no significant effects. The apoptosis index was not altered by hepatectomy or immunosuppressants. Our data indicate that, in the growing rat, CsA and Tac have negative effects on hepatocyte proliferation and have no effect on the hepatocyte apoptosis.

Congenital heart disease and pediatric liver transplantation: complications and outcome

Mild and moderate CHD in infants do not always need surgical correction but possibly augment the operative risk of patients with ESLD undergoing OLT. The aim of this study is to assess the intraoperative and post-operative complications and evaluate the outcome of these patients. The records of 196 patients were reviewed retrospectively in a cohort study, 50 CHD were found in 36 patients undergoing 41 OLT procedures. The prevalence of CHD during pediatric OLT was 18%. Our data identified no significant differences between the two groups of patients, regarding hypotension, desaturation, acidosis, and bleeding during the procedure. Post-operatively, no differences were observed in the hemodynamic, respiratory, and renal systems as no differences were detected for graft failure, surgical complications, infection, and rejection rates. Mortality is comparable in the two groups as are re-transplantation and recovery rates. The above mentioned results indicate that minor cardiac defects do not significantly influence the operative risk of these patients.

Experimental models of hepatectomy and liver regeneration using newborn and weaning rats

OBJECTIVES

Liver regeneration is a complex process that has not been completely elucidated. The model most frequently used to study this phenomenon is 70% hepatectomy in adult rats; however, no papers have examined this effect in developing animals. The aims of the present study were: 1) to standardize two models of partial hepatectomy and liver regeneration in newborn suckling and weaning rats, and 2) to study the evolution of remnant liver weight and histological changes of hepatic parenchyma on the days that follow partial hepatectomy.

METHODS

Fifty newborn and forty-four weaning rats underwent 70% hepatectomy. After a midline incision, compression on both sides of the upper abdomen was performed to exteriorize the right medial, left medial and left lateral hepatic lobes, which were tied inferiorly and resected en bloc. The animals were sacrificed on days 0 (just after hepatectomy), 1, 2, 3, 4 and 7 after the operation. Body and liver weight were determined, and hepatic parenchyma was submitted to histological analysis.

RESULTS

Mortality rates of the newborn and weaning groups were 30% and 0%, respectively. There was a significant decrease in liver mass soon after partial hepatectomy, which completely recovered on the seventh day in both groups. Newborn rat regenerating liver showed marked steatosis on the second day. In the weaning rat liver, mitotic figures were observed earlier, and their amount was greater than in the newborn.

CONCLUSIONS

Suckling and weaning rat models of partial hepatectomy are feasible and can be used for studies of liver regeneration. Although similar, the process of hepatic regeneration in developing animals is different from adults.

Prevalence of antibodies against hepatitis A virus among the Kuikuro and Kaiabi Indians of Xingu National Park, Brazil

A seroprevalence study to detect total antibodies against Hepatitis A Virus was done with 220 samples from 589 Native Indians from Xingu National Park, Brazil, in five Kaiabi and Kuikuro villages, the most populous ethnic groups. Using a commercial immunoassay kit we detected 97.7% positive samples (95% Confidence Interval: 95%-99%). We noticed a precocious seroconversion, before the age of six years, when the disease is usually asymptomatic. These results are similar to those found in the literature in non-Indian population studies of the Northern, Northeastern and West Central regions of Brazil. They suggest that it is not necessary to introduce vaccination against Hepatitis A in these highly endemic populations.

Expression of interleukin 6 and apoptosis-related genes in suckling and weaning rat models of hepatectomy and liver regeneration

BACKGROUND/PURPOSE

The most commonly used model to study the mechanisms of liver regeneration is the adult rat submitted to 70% to 80% hepatectomy. However, there are no studies using newborn or weaning rat models. The process of liver regeneration includes both the hypertrophy and hyperplasia of cells (processes regulated by growth factors and cytokines, mainly interleukin 6 [IL-6]) as well as apoptosis, or programmed cell death (a process regulated mainly by the Bcl-2 family of proteins). Proapoptotic proteins in this family include Bax and Bak. Conversely, Bcl-2 and Bcl-XL are antiapoptotic regulators. Therefore, to expand our understanding of liver regeneration, our study had 2 goals: first, to standardize 2 animal models of hepatectomy and liver regeneration using the newborn suckling and the weaning rat and second, to quantitate the expression levels of IL-6 and several members of the Bcl-2 gene family during the regeneration process.

METHODS

To create the experimental models, newborn suckling rats (age, 5-7 days; weight, 6-10 g) and weaning rats (age, 21-23 days; weight, 30-50 g) underwent 70% hepatectomy. The animals were subsequently sacrificed at days 1, 2, 3, 4, and 7 after hepatectomy, and the remnant liver lobes were harvested for routine histologic examination. Groups of healthy animals not operated on served as controls. For the experimental study, 6 newborn rats and 6 weaning rats underwent hepatectomy. The animals were killed 1 day after liver resection and the remnant livers were harvested to assess gene expression by quantitative reverse transcription-polymerase chain reaction. The hepatectomized groups were compared with control and sham groups.

RESULTS

During the creation of the experimental models, 70% of the suckling animals and all the weaning animals survived the hepatectomy. The decreased liver weight was completely restored to control levels by day 7 after hepatectomy. Histologically, the remnant livers of both hepatectomy groups exhibited steatosis, tumefaction of hepatocytes, and mitosis, which ceased at 7 days after the hepatectomy. The weaning rat model showed more robust gene expression responses. Specifically, expression levels of IL-6 gene were significantly increased after both surgical insult (sham group) and hepatectomy. However, this increase was significantly higher in the latter group. Furthermore, hepatectomy promoted a decrease in the expression levels of the proapoptotic genes and an increase in the expression levels of Bcl-2.

CONCLUSIONS

Our data indicate that regulation of both IL-6 and genes involved in apoptosis are strongly implicated in the mechanisms of liver regeneration and that the weaning rat model represents an attractive model system for future investigations in this area.

Living donor liver transplantation for biliary atresia: a single-center experience with first 100 cases

The aim of this study is to present our institutional experience in living donor liver transplantation (LDLT) as a treatment for end-stage liver disease in children with biliary atresia (BA). A retrospective review of transplant records was performed. One hundred BA patients (52 males and 48 females) underwent LDLT. The mean follow-up period was 85.5 months. The mean age was 2.4 years. The mean preoperative weight, height, and computed GFR were 12.2 kg, 82.5 cm, and 116.4 ml/min/1.73 m2, respectively. Twenty-seven patients were below 1 year of age, and 49 patients were below 10 kg at the time of transplantation. Ninety-six had had previous Kasai operation prior to transplant. The mean recipient operative time was 628 min. The mean recipient intraoperative blood loss was 176 ml. Thirty-five did not require blood or blood component transfusion. The left lateral segment (64) was the most common type of graft used. There were 27 operative complications which included 3 reoperations for postoperative bleeding, 9 portal vein, 4 hepatic vein, 4 hepatic artery, and 7 biliary complications. There was one in-hospital mortality and one retransplantation. The overall rejection rate was 20%. The overall mortality rate was 3%. The 6-month, 1-year and 5-year actual recipient survival rates were 99%, 98% and 98%, respectively.

Management of a cadaveric orthotopic liver transplantation in a pediatric patient with complex congenital heart disease

Pediatric orthotopic liver transplantations (OLT) are commonly performed nowadays. Two primary reasons for OLT in children are complications from either extrahepatic biliary atresia (EHBA) or inborn errors of metabolism. However, congenital liver disease may be associated with significant other congenital abnormalities. We present a case of a successful OLT in a pediatric patient with a history of EHBA, situs inversus, and complex congenital heart disease. The cardiac anomalies include dextrocardia, absence of the atrial septum (single atrium), single atrioventricular valve (a-v canal), and an incomplete ventricular septum. Prior surgery include a Kasai procedure for EHBA, banding of the proximal main pulmonary artery, and Broviac catheter placement. We present the anesthesia concerns and management for this complicated case.

Successful treatment of de novo autoimmune hepatitis and cirrhosis after pediatric liver transplantation

Over a 15-yr period of observation, among the 205 children who underwent liver transplantations, one of them developed a particular type of late graft dysfunction with clinical and histological similarity to autoimmune hepatitis. The patient had alpha1-antitrypsin deficiency and did not previously have autoimmune hepatitis or any other autoimmune disease before transplantation. Infectious and surgical complications were excluded. After repeated episodes of unexplained fluctuations of liver function tests and liver biopsies demonstrating reactive or a biliary pattern, without any corresponding alteration of percutaneous cholangiography, a liver-biopsy sample taken 4 yr after the transplant showed active chronic hepatitis progressing to cirrhosis, portal lymphocyte aggregates, and a large number of plasma cells. At that time, autoantibodies (gastric parietal cell antibody, liver-kidney microsomal antibody, and anti-hepatic cytosol) were positive and serum IgG levels were high. Based on these findings of autoimmune disease, a diagnosis of 'de novo autoimmune hepatitis' was made. The treatment consisted of reducing the dose of cyclosporine, reintroduction of corticosteroids, and addition of mycophenolate mofetil. After 19 months of treatment, a new liver-biopsy sample showed marked reduction of portal and lobular inflammatory infiltrate, with regression of fibrosis and of the architectural disruption. At that time, serum autoantibodies became negative. The last liver-biopsy sample showed inactive cirrhosis and disappearance of interface hepatitis and of plasma cell infiltrate. Presently, 9 yr after the transplantation, the patient is doing well, with normal liver function tests and no evidence of cirrhosis. Her immunosuppressive therapy consists of tacrolimus, mycophenolate mofetil, and prednisolone. In conclusion, the present case demonstrates that de novo autoimmune hepatitis can appear in liver-transplant patients despite appropriate anti-rejection immunosuppression, and triple therapy with tacrolimus, mycophenolate mofetil, and prednisolone could sustain the graft and prevent retransplantation.

Nonvascular complications in pediatric liver recipients: multidetector computed tomography evaluation

In pediatric liver transplantation postoperative diagnosis of complications is crucial for graft salvage. Multidetector computed tomography (MDCT) is a technique to evaluate complications. In this study we present nonvascular abdominal complications encountered in pediatric recipients after liver transplantation. We retrospectively examined 113 MDCT examinations in 43 pediatric patients who underwent liver transplantation between 1997 and 2005. Computed tomography (CT) examinations were made by a 16-detector multislice CT scanner. The pathological findings on CT images were: intraperitoneal free fluid, intrahepatic bile duct dilatation, graft liver infarction, perihepatic and intraperitoneal fluid collections (six biloma), colonic and/or intestinal dilatation, splenic infarction, perihepatic hematoma, right adrenal hemorrhage, perihepatic abscess, incisional hernia, intrahepatic biloma and periportal collar. In one patient intestinal hemorrhage was suspected. Intestinal perforation was suspected in three patients. Among these three patients, one patient died before any surgical intervention. In two patients the diagnosis was confirmed at surgery. In pediatric patients, the short examination time, brief sedation duration, and high-resolution images make MDCT an effective radiological method to evaluate nonvascular transplant complications.

An alternative method of arterial reconstruction in pediatric living donor liver transplantation with the recipient right gastroepiploic artery

The classical method for arterial reconstruction in pediatric living donor liver transplantation using left lateral segment consists of end-to-end anastomosis between the donor left hepatic artery and the recipient right hepatic artery. In the present case, an intra-operative hepatic artery thrombosis occurred because of extensive intima wall dissection of the recipient hepatic artery. The patient was a 6-yr-old boy with fulminant hepatic failure, who underwent living donor partial liver transplantation with left lateral segment from his father. The graft was irrigated by a left hepatic artery and an accessory left hepatic artery from gastric artery, both arteries with diameter of <2 mm. These arteries were anastomosed to the recipient right and left hepatic arteries, respectively. Before performing the bile duct reconstruction it was noted that these anastomoses were occluded by clots of blood. An extensive subintimal dissection of the recipient hepatic artery was the cause of this problem. The creation of a new anastomosis by using a more proximal part of this artery without subintimal dissection was judged impossible. Then, the right gastroepiploic artery was mobilized and an anastomosis was performed with the donor left hepatic artery in an end-to-end fashion. Arterial blood flow to the graft was established successfully and the patient's postoperative recovery was excellent. Fifteen days after the transplantation, an angiotomography demonstrated a good hepatic arterial blood flow. The patient is now alive and well, 4 months after the transplantation. In conclusion, the method of hepatic graft arterialization described here is an important option for patients who undergo living donor or split liver transplantation.

Post-portoenterostomy triangular cord sign prognostic value in biliary atresia: a prospective study

The triangular cord sign (TC sign) is a sensitive and specific tool in prompt diagnosis of extrahepatic biliary atresia. The objective of this study is to evaluate post-operative TC sign presence in outcome prediction of infants with biliary atresia after Kasai hepato-portoenterostomy 27 infants and children with biliary atresia underwent 122 ultrasound examinations using both 5 MHz and 7 MHz convex linear transducers in 33 months follow up. For all infants TC sign identification was included pre-operatively, ultrasound was done 2 weeks post-operatively then bimonthly for 3 months, monthly for 2 months and every 3 months thereafter. 14 (53.8%) had post-operative TC sign. Once post-operatively positive, it remained positive throughout the study. It did not reappear in an initially post-operatively TC sign negative infant. Those having post-operative TC sign had statistically worse outcomes (0 became anicteric, 2 improved, 7 had progressive disease and 6 died) than those with a negative TC sign (p = 0.04) (3 became anicteric, 5 improved, 2 progressed and 1 died). Presence of TC sign post-operatively correlated with measure of removal of all fibrous cone at porta-hepatis during portoenterostomy (p = 0.026). Post-portoenterostomy TC sign is associated with more morbidity and mortality; and reflects inadequate surgical technique.

Complicações biliares pós-transplante hepático intervivos

OBJETIVO: A reconstituição biliar no transplante hepático intervivos é associada à elevada taxa de complicações. O objetivo do presente estudo é apresentar a nossa experiência com as complicações biliares pós-transplante hepático intervivos e o seu tratamento. MÉTODO: De um total de 300 transplantes hepáticos, 51 (17%) foram com doadores vivos. Todos receptores tinham o grupo sangüíneo ABO idêntico aos dos doadores. Os prontuários eletrônicos dos receptores foram avaliados para determinar a presença e o tipo de anomalia da via biliar, o tipo de reconstituição da via biliar, presença de complicações vasculares e biliares e o método e o resultado do tratamento das complicações. RESULTADOS: A via biliar era dupla em sete enxertos (16,7%) e tripla em dois (4,8%) enxertos do lobo hepático direito. Nos demais, ela era única. O tipo de reconstituição mais comum foi a hepaticohepaticostomia única ou dupla (38 transplantes; 75%). Complicações biliares ocorreram em 21 pacientes (41,2%) e incluíram fístula biliar em 11 (21,6%), estenose biliar em seis (11,8%) e fístula com estenose em quatro (7,8%). O local da fístula foi na anastomose biliar em 11 pacientes (21,6%) e na superfície cruenta do fígado em quatro (7,8%). O tratamento consistiu de inserção de prótese biliar em oito, papilotomia em um, retransplante em dois que tinham trombose da artéria hepática e sutura do ducto em um. A fístula fechou com o tratamento conservador em três pacientes. A maioria dos pacientes com estenose biliar foi tratada com dilatação seguida da colocação de prótese biliar. CONCLUSÕES: As complicações biliares são freqüentes após o transplante hepático intervivos e são associadas à elevada taxa de morbidade e mortalidade.