Relationship between vasoactive intestinal peptide and intrapulmonary vascular dilatation in children with various liver diseases

AIM: To evaluate the potential of vasoactive intestinal peptide (VIP) as a pathogenic factor of intrapulmonary vascular dilatation (IVD) in hepatopulmonary syndrome (HPS). BACKGROUND: HPS comprises a triad comprising liver dysfunction, IVD and hypoxaemia. Although the pathogenesis of the process has not been elucidated, many vasodilating substances, such as VIP, have been implicated in the development of pulmonary vascular abnormalities. IVD can be detected by contrast-enhanced echocardiography (CEE) before the development of abnormal gas exchange. METHODS: Forty-two children (20M, 22F; mean age 4.39 +/- 4.17 y) with various liver diseases who attended the paediatric liver clinic of King Chulalongkorn Memorial Hospital between March 2000 and February 2001 were recruited to the study. Each patient was tested for transcutaneous O2 saturation, CEE (applying the agitated normal saline technique), liver function test and serum VIP level. RESULTS: Fourteen of the 42 patients (33%) were CEE positive. Only one of the 14 patients had associated hypoxia and clinical cyanosis. The serum VIP levels of children with liver disease were significantly higher than those of the controls (60.21 +/- 35.04 pg/ml vs 43.71 +/- 34.61 pg/ml, p = 0.03). CEE-positive children tended to have higher serum VIP levels than CEE-negative children (72.65 +/- 40.31 vs 53.99 +/- 31 pg/ml, p = 0.3). The serum VIP levels of biliary atresia (BA) patients with favourable outcomes (serum bilirubin < or = 34 micromol/L) were not significantly different from those with unfavourable outcomes (serum bilirubin > 34 micromol/L) (42.95 +/- 14.53 pg/ml vs 66.07 +/- 32.17 pg/ml, p = 0.5). CONCLUSIONS: CEE is a non-invasive test for early detection of IVD in children with liver disease. VIP is not solely responsible for the pathogenesis of IVD in HPS. Further studies are required to determine which substances cause the development of IVD.     

Preoperative pulmonary assessment of children for liver transplantation

Abstract:  Pulmonary assessment should be part of the preoperative investigation of pediatric patients with chronic liver disease undergoing liver transplantation, as it allows the identification of pulmonary alterations that influence candidacy for transplantation and survival. To describe pulmonary changes found in pediatric patients who were candidates for liver transplantation. Retrospective study of 17 pediatric liver transplant candidates undergoing preoperative pulmonary evaluation assessing pulmonary clinical data, arterial blood gas analysis, CXR, respiratory function test by spirometry, pulmonary scintigraphy, and CEE. Ten patients presented normal chest roentgenograms. The most common radiographic change was interstitial infiltrate in the lung bases. Of the five patients with PaO₂ <70 mmHg, four had cyanosis and dyspnea and two were diagnosed with HPS with intrapulmonary shunt evidenced by contrast echocardiogram. Two patients presented with intrapulmonary shunt but without hypoxemia. Spirometry was normal in six patients, restrictive disturbance was evidenced in one patient, obstructive in three, and combined in two. The most common scintigraphic change was heterogeneous pulmonary perfusion. Pulmonary assessment should be performed routinely in pediatric patients prior to liver transplantation, even in asymptomatic patients. Pulmonary assessment may indicate changes such as HPS that can increase postoperative morbidity/mortality.     

Onset ages of hepatopulmonary syndrome and pulmonary hypertension in patients with biliary atresia

Purpose

Hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PoPH) are extrahepatic complications of biliary atresia (BA). Their detection is sometimes delayed, which may result in missed opportunities for liver transplantation. The aim of this study was to determine the onset ages of HPS and PoPH in BA patients.

Methods

BA patients followed at our institution were identified. Patients visited our clinic for routine blood work, as well as regular electrocardiography, chest X-rays, and arterial blood gas tests. Lung perfusion scintigraphy and cardiac ultrasound were performed to diagnose HPS. Cardiac catheterization was conducted to diagnose PoPH.

Results

The study population consisted of 88 BA patients. The median follow-up duration was 11.6 years (range 0.8–26.0 years). Six patients (6.8%) developed HPS and three patients (3.4%) developed PoPH. The median age of onset of HPS was significantly younger than that of PoPH (HPS: 4 years, PoPH: 15 years, P < 0.019). Two patients (66%) with PoPH died, while all patients with HPS survivied.

Conclusion

The onset of HPS was significantly earlier than that of PoPH. The mortality rate was high in patients with PoPH. Teenagers with BA should receive routine cardiac echocardiograms to detect PH in its early stages.

     

Development of hepatopulmonary syndrome and portopulmonary hypertension in a paediatric liver transplant patient

BACKGROUND: Hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PPH) are pulmonary vascular disorders which occur in patients with severe liver disease and/or portal hypertension. Although these syndromes are frequently diagnosed in patients undergoing assessment for liver transplantation, they seldom occur in the same patient. METHOD: This report describes a female paediatric patient, born with extra-hepatic biliary atresia, who required liver transplantation, at the age of 15, for secondary biliary cirrhosis. She had severe HPS prior to her first liver transplant, which resolved rapidly following surgery, as well as indirect evidence for PPH. She required a second liver transplant 1 yr later for chronic rejection. Whilst evaluating the patient for a third liver transplant, 4 yr later, severe PPH was discovered. The patient died 3 months later from right heart failure. CONCLUSION: HPS and PPH may coexist however they may show differing responses to liver transplantation with progression of PPH despite the resolution of HPS.     

Long‐term outcome and management of hepatopulmonary syndrome in children

Al‐Hussaini A, Taylor RM, Samyn M, Bansal S, Heaton N, Rela M, Mieli‐Vergani G, Dhawan A. Long‐term outcome and management of hepatopulmonary syndrome in children.
Pediatr Transplantation 2010:14:276–282. © 2009 John Wiley & Sons A/S. Abstract: We aim to report a single center experience of the management and long term outcome of HPS in pediatric liver transplant recipients. A retrospective review of children with HPS from 1990 to 2004. Inclusion criteria: liver disease or portal hypertension, hypoxemia (PaO₂ < 70 mmHg or SaO₂ < 95%) and intrapulmonary shunting documented by macroaggregated albumin scan ratio of >4% (classified mild group [<20%], moderate group [20–40%] and severe group [>40%]). Resolution of HPS post‐liver transplant was defined as PaO₂ > 70 mmHg or SaO₂ > 95%. Eighteen children (six male [34%], median age at diagnosis of HPS 8.6 [1–15.5] yr) had HPS: biliary atresia (n = 8), idiopathic biliary cirrhosis (n = 4), progressive intrahepatic cholestasis (n = 2), miscellaneous (n = 4). The majority had mild shunting (n = 8). Fourteen underwent transplantation with resolution of HPS in 13. Six developed complications: hepatic artery thrombosis (n = 4), biliary (n = 2). Four children died (28%), two pretransplant. There was a tendency towards shunt fraction worsening to a slower degree over time. One‐yr survival rate post‐transplant was 93%. Median PaO₂ was significantly lower in non‐survivors compared to survivors (43 vs. 55.2 mmHg, p = 0.03). There was correlation between oxygen parameters pretransplant and time to HPS resolution post‐transplant. HPS is reversible after transplant, but is associated with increasing mortality and morbidity.     

Brain abscess in hepatopulmonary syndrome associated with biliary atresia

The first‐choice therapy for biliary atresia (BA) is Kasai hepatoportoenterostomy, which has been shown to greatly improve outcome. Various long‐term complications, however, such as portal hypertension and hepatopulmonary syndrome (HPS), can occur in patients with native liver. A rare case of brain abscess in an 11‐year‐old girl with HPS associated with BA is reported. The patient underwent hepatoportoenterostomy for BA at 53 days of age, with resolution of hyperbilirubinemia. At 10 years of age, she was diagnosed with severe HPS with right‐to‐left shunting, and preparations for liver transplantation proceeded. Three months after the diagnosis, she had a right parietal brain abscess. Given that the brain abscess enlarged in size, surgical drainage of the brain abscess was performed. The postoperative course was uneventful, but a slight left hemiplegia remained at discharge. The presumed mechanism of abscess formation in HPS may be right‐to‐left bacterial transit through intrapulmonary vascular dilatations and/or arteriovenous fistulae.     

Successful liver retransplantation for recurrent hepatopulmonary syndrome

HPS is defined as arterial hypoxemia because of pulmonary vasodilation as a result of cirrhotic or non-cirrhotic portal hypertension. This report describes a teenager with HPS because of primary sclerosing cholangitis/autoimmune hepatitis overlap syndrome requiring OLT. HPS resolved completely within three months of OLT, but recurred again at 12 months post-OLT following liver dysfunction secondary to a biliary stricture. She underwent a second OLT successfully and remains well two yr and three months post-second OLT. Recurrent HPS after OLT may occur because of graft dysfunction and as this novel case illustrates, retransplantation may lead to a successful outcome.     

Late complications of biliary atresia: hepatopulmonary syndrome and portopulmonary hypertension

Children with biliary atresia (BA) following Kasai portoenterostomy have a high risk for portal hypertension, however, while variceal and hemorrhagic complications have been more commonly studied, less frequent but no less possibly devastating complications of hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PPH) remain less well understood. HPS and PPH both occur in a setting of portal hypertension, however, paradoxically patients with HPS develop pulmonic vasculature dilation leading to shunting and hypoxia, while those with PPH develop an opposite progression of pulmonary vasoconstriction eventually leading to cor pulmonale and decompensation. Given the near diametric evolution of diseases, HPS and PPH differ widely in therapy, though liver transplantation can have a role for treatment in either disease state. We reviewed our series of 320 pediatric patients with biliary atresia treated at our institution over 44 years, highlighting two cases that developed HPS and PPH, respectively, using these cases in further discussion of hepatopulmonary syndrome and portopulmonary hypertension regarding disease etiology, diagnosis, management, and prognosis. The complicated nature of these processes demand a careful multidisciplinary approach to optimize patient outcomes, including mindful evaluation for when transplantation may offer benefit.     

Nitric oxide for post‐liver‐transplantation hypoxemia in pediatric hepatopulmonary syndrome: Case report and review

Schiller O, Avitzur Y, Kadmon G, Nahum E, Steinberg RM, Nachmias V, Schonfeld T. Nitric oxide for post‐liver‐transplantation hypoxemia in pediatric hepatopulmonary syndrome: Case report and review.
Pediatr Transplantation 2011: 15: E130–E134. © 2010 John Wiley & Sons A/S. Abstract: HPS is rare in the pediatric population. Liver transplantation is the ultimate treatment for severe HPS. There are only a few case reports and one series of children in whom HPS was the main indication for liver transplantation. Outcome was good in most of them, with full regression of the pulmonary process. However, hypoxemia in the early post‐operative course can have severe consequences, and effective treatment modalities are needed. There are rare instances of the use of iNO for the treatment of post‐operative hypoxemia. We describe a 10.5‐yr‐old boy with severe HPS owing to chronic liver disease after bone marrow transplantation. Liver transplantation from a living related donor (the same sister who donated the bone marrow) was complicated by severe hypoxemia on POD 2. iNO was administered via the ventilator circuit and, after extubation, through nasal prongs. It was slowly tapered down and stopped on POD 10. The child had an otherwise uneventful course and was discharged home on POD 21 with normal oxygen saturation. Liver transplantation should be offered to children with severe HPS. iNO can reverse the hypoxemia that may occur after the operation.     

Upper gastro-intestinal tract bleeding in cirrhotic children candidates for liver transplantation

Signs of portal hypertension, history of upper gastro-intestinal tract bleeding episodes and outcome of the latter were recorded in 76 cirrhotic children evaluated for liver transplantation. Fifty-three (70%) had varices and 22 (29%) had experienced upper gastro-intestinal tract bleeding. Of these 22, 19 bled from varices and 3 from ulcers. Non bleeding ulcers were also found in five patients bleeding from varices. Iterative sclerotherapy controlled acute variceal bleeding in all but one patient in whom emergency transplantation was performed. Six of the eight patients with ulcers were successfully treated by the H2 histamine receptor antagonist ranitidine. We conclude that iterative sclerotherapy is efficient to control acute variceal bleeding and prevents recurrent bleeding in children with end-stage liver diseases awaiting liver replacement. Bleeding asymptomatic ulcers are frequent and respond to H2 histamine receptor antagonists.     

Hepatopulmonary syndrome associated with nodular regenerative hyperplasia after liver transplantation in a child

HPS is a significant complication of portal hypertension in children with chronic liver disease and is an established indication for LT. It is characterized clinically by the triad of pulmonary vascular dilatation causing hypoxemia in the setting of advanced liver disease. NRH, a cause of non‐cirrhotic portal hypertension, is characterized by diffuse benign transformation of the hepatic parenchyma into small regenerative nodules with minimal or no fibrosis. Development of NRH and HPS in pediatric LT recipients has not been reported, although occasional cases have been reported in adult LT recipients. In this report, we discuss a case of a three‐yr‐old male who developed HPS, two yr after LT. Pulmonary and cardiac causes for hypoxemia were ruled out by appropriate investigations including a chest X ray, echocardiogram, cardiac catheterization, and a CT angiographic study. The diagnosis of HPS was confirmed via bubble echocardiogram that demonstrated intrapulmonary shunting. Open liver biopsy revealed marked NRH. The patient underwent liver retransplantation that resulted in complete reversal of his pulmonary symptoms and normal oxygen saturations within three months after LT.     

Autoimmune hepatitis in a child presenting with hepatopulmonary syndrome (HPS)

HPS has been described in 9–20% of children with end‐stage liver disease. We present a case of a previously, asymptomatic nine‐yr‐old incidentally found to have low oxygen saturation. Physical exam was remarkable for digital clubbing, splenomegaly and orthodeoxia. Laboratory evaluation revealed a low platelet count, hyperammonemia, and prolonged coagulation studies. Sonography showed evidence of splenomegaly and portal venous hypertension. High resolution CT thorax and CTA were normal. HPS was confirmed by agitated saline contrast enhanced echocardiography and Tc‐99m MAA scan with evidence of intrapulmonary vascular dilatations. Liver biopsy was performed and consistent with autoimmune hepatitis. A high clinical index of suspicion should be maintained for HPS in pediatric patients who have unexplained hypoxemia as typical signs and symptoms of severe liver disease are often absent. In this report, we discuss a case of HPS complicated AIH in a pediatric patient and review the relevant literature.     

Sudden death caused by unsuspected pulmonary arterial hypertension, 10 years after surgery for extrahepatic biliary atresia

A case of extrahepatic biliary atresia presenting with an acute respiratory episode and rapid deterioration, 10 years after a successful portoenterostomy and a very active life, was the setting of unsuspected severe pulmonary arterial hypertension leading to sudden death. The pulmonary arteries showed widespread plexiform lesions, thickening of the muscular media, and subendothelial proliferation. Occasionally, eccentric arterial obstructive lesions and fibrinous thrombi were observed. There was marked reduction of preacinar arterioles with a consequent increase in the alveolar/arterial ratio. The pulmonary veins showed arterialization of their walls. There was marked hypertrophy of myocardial fibres in the right ventricle together with foci of myocardial degeneration and fibrosis. Areas of endocardial thickening were observed in both ventricles. The absence of clinical indicators of pulmonary arterial hypertension at any but the terminal stages of the disease precluded any form of conservative management. Lung-heart and presumably liver transplantation might have been the only option. Prospective assessment of pulmonary function and haemodynamic studies should be considered in cirrhotic patients with portal hypertension.     

移植物体重比对左外叶小儿活体肝移植术后短期肝功能的影响

目的 探讨移植物体重比(Graft recipient body weight ratio,GRBW)对小儿活体左外叶肝移植术后短期肝功能恢复的影响.方法 2006年6月至2009年3月共施行活体肝移植25例,其中17例左外叶活体肝移植患儿作为研究对象.分别于术后1～7 d测量患儿肝脏功能,采用SPSS15.0统计软件分析了解GRBW与术后短期肝功能恢复的相关性.结果 ①肝移植术后肝功能恢复良好(P<0.000 1);②GRBW与术后谷丙转氨酶(ALT)变化呈正相关(P<0.05)、与AST变化呈负相关(P<0.05).结论 左外叶小儿活体肝移植GRBW对于术后肝功能恢复意义重大,移植术中应充分保证足够的GRBW比值.     

Pediatric living donor liver transplantation for biliary atresia with hepatopulmonary syndrome: the gift of a second wind

Purpose

Hepatopulmonary syndrome (HPS) is a progressive, deteriorating complication of end-stage liver disease (ESLD) that occurs in 13?C47% of liver transplant candidates. Although LT is the only therapeutic option for HPS, it has a high morbidity and mortality, especially in patients with severe hypoxemia before transplantation, but the course of HPS after living donor liver transplantation (LDLT), especially for biliary atresia (BA) patients is not well established.

Patients and methods

The present study evaluated 122 patients who received an LDLT for BA and of these, 3 patients had HPS at the time of LDLT in a single-center series.

Results

Two patients of the HPS patients them had biliary and/or vascular complications, but they recovered uneventfully with interventional treatment. None of the patients required supplemental oxygen and had no residual cardiopulmonary abnormalities at a follow-up of more than 24?months.

Conclusion

Although a series of three patients is too small for definitive conclusion and further investigations must be conducted, pediatric LDLT can be a favorable therapeutic option for HPS.     

Liver transplantation in very small infants

BACKGROUND: This study examines the results of liver transplantation (LT) in children 5 kg or less. Reports suggest an increased morbidity and mortality in children weighing 5 kg or less as compared to larger children. However, over half of all children needing LT are <1 year old. Improving outcomes in very small children is a major goal of liver transplantation. METHODS: All children under 21 years of age transplanted from January 1990 to June 2005 were included in this study. One hundred sixty-eight primary liver transplants were done: 61 in children less than one year of age and 20 in infants weighing 5 kg or less at LT (2 to 5 kg). These 20 infants underwent 23 transplants. Whole organs were used in 39% of transplants, and reduced or split grafts were used in 61%. Arterial reconstruction using aortic conduits was done in 22%. Analysis included Fischer's exact or Chi square test for non-parametric analysis while patient survival was calculated using the Kaplan-Meier method test with differences in survival assessed using the log rank test. RESULTS: Five-year survival for infants 5 kg or less was 74%, and graft survival was 60%, which was not different from patients transplanted that were >5 kg. There were three perioperative deaths, one from primary graft non-function, and two from portal vein thrombosis. There were no bile leaks or hepatic artery thromboses. Bacterial, fungal, and viral infections made up the vast majority of the postoperative complications (65%), with viral infections resulting in two graft losses requiring re-transplantation. Rejection occurred in 25% of patients, of which one required OKT3. Five of the 23 liver transplants in infants less than 5 kg were done prior to 1996, with a five-year graft survival of only 20%. Improvements in technique and postoperative care after 1996 led to improved graft and patient survival of 77% and 86% respectively. CONCLUSIONS: Liver transplantation for infants weighing less than 5 kilograms can be technically challenging but can have equivalent graft and patient survival when compared to larger children requiring liver transplantation. Infants should not be denied liver transplantation based on weight alone.     

儿童肾血管性高血压29例诊断方法的回顾性分析

目的 探讨儿童肾血管性高血压（RVH）的早期诊断方法。 方法 回顾性分析北京大学第一医院1996年1月至2011年6月确诊的RVH患儿,分析贻误诊治情况,以及临床症状、影像学检查结果对RVH的诊断价值。 结果 ①29例确诊RVH患儿进入分析,其中男18例,女11例。起病年龄0.5~15岁,平均年龄（7.0±4.4）岁。从首发症状出现至确诊时间为15 d至7年,平均确诊时间11个月。9例（31.0%）患儿起病6个月后确诊,曾分别被误诊为胃肠炎、癫、肾脏和心脏疾病等。3例患儿以头痛伴呕吐起病,补液出现抽搐后发现高血压。首发症状以头痛（10例,34.5%）、呕吐（10例,34.5%）和抽搐（9例,31.0%）多见。起病时平均收缩压和舒张压分别为182和127 mmHg。②单侧肾动脉狭窄25例,双侧肾动脉狭窄4例。23例通过肾动脉造影确诊,其中17例单侧肾动脉狭窄患儿中10例超声检查显示双肾长径相差>1.5 cm;血管超声对肾动脉狭窄检出率为31.3%（5/16例）;CT对肾动脉狭窄检出率为50.0%（3/6例）;肾动态显像对肾功能受损检出率为93.8%（15/16例）。通过肾血管超声检查确诊4例,通过肾动脉超声检查及CT检查确诊1例,通过肾动脉超声检查和肾动脉MRA检查确诊1例。③16/18例（88.9％）卧位血浆肾素和血管紧张素水平增高。12/29例（41.4%）存在低钾血症。10/29例（34.5%）确诊为多发性大动脉炎。 结论 儿童RVH贻误诊断率较高,对于有头痛、呕吐和抽搐者应首先测量血压,尤其在补液治疗前。肾动态显像有助于早期发现患侧肾功能受损,血浆肾素和血管紧张素增高、低钾血症、双肾大小不对称对于诊断具有提示意义,肾血管超声和CT检查敏感度有限,可疑患儿应尽早行肾动脉造影检查。确诊RVH后应尽可能进行病因诊断,尤其应确定是否存在大动脉炎以指导治疗。     

Alpha1-antitrypsin deficiency-associated liver disease progresses slowly in some children

BACKGROUND: A prospective nationwide screening study initiated more than 20 years ago in Sweden has shown that clinically significant liver disease develops in only 10% to 15% of alpha1-antitrypsin (AT)-deficient children. This study provides information about 85% to 90% of those children, many of whom had elevated serum transaminases in infancy but have no evidence of liver injury by age 18 years. However, there is relatively limited information about the course of alpha1-AT-deficient children who have cirrhosis or portal hypertension. Based on several anecdotal experiences, we have been impressed by the relatively slow progression and stable course of the liver disease in some of these children. METHODS: We reviewed the course of patients with homozygous PIZZ alpha1-antitrypsin deficiency seen at this institution since establishing a patient database 16 years ago. RESULTS: Of 44 patients with alpha1-AT deficiency, 17 had cirrhosis, portal hypertension, or both. Nine of the 17 patients with cirrhosis or portal hypertension had a prolonged, relatively uneventful course for at least 4 years after the diagnosis of cirrhosis or portal hypertension. Two of these patients eventually underwent liver transplantation, but seven are leading relatively healthy lives for up to 23 years while carrying a diagnosis of severe alpha1-AT deficiency-associated liver disease. Patients with the prolonged stable course could be distinguished from those with a rapidly progressive course on the basis of overall life functioning but not on the basis of any other more conventional clinical or biochemical criteria. CONCLUSIONS: These data provide further evidence for the variable severity of liver disease associated with alpha1-AT deficiency and indicate that some patients have chronic, slowly progressing or nonprogressing cirrhosis.     

Morbidity and mortality of children with chronic liver diseases who were listed for liver transplantation in Iran

Liver transplantation is the treatment of choice for end-stage liver disease in children, but donor shortage is still a main problem in this age group. The aim of the present study is to evaluate the complications and mortality of liver disease in children waiting for transplantation. We analyzed medical records of 83 children aged <18 yr, who were listed for liver transplantation but the organ was not available for them between 1999 and 2006. The outcome was assessed from their records or follow-up data. Among the children (mean age, 8 +/- 5 yr; 50.5% boys) listed for liver transplantation, but the organ was not available for them, the common causes of cirrhosis were biliary atresia (27.7%) and cryptogenic (24.1%). The mean follow-up duration was 14 +/- 13.4 months (range 0.5-54 months). Sixty-seven (80.7%) patients developed one or more complications while awaiting transplantation. The most common complications were gastrointestinal bleeding (44.6%), spontaneous bacterial peritonitis (36.1%), infectious complications (28.9%), encephalopathy (24.1%), renal (18.1%), and pulmonary problems (10.8%). Fifty-one (61.4%) patients needed hospital admission because of complications and 26 (31.3%) patients died while awaiting transplantation. About two-thirds of children listed for liver transplantation needed hospital admission because of complications and one-third of them died without any liver transplantation. It seems that more split liver transplantation as well as the introduction of a live-related program in our center will provide many benefits to our children.     

Outcome of bowel perforation after pediatric liver transplantation

Abstract:  Bowel perforation is one of the causes of mortality after pediatric liver transplantation. The aim of this study was to evaluate the incidence, risk factors, clinical presentations, and outcomes of bowel perforation in pediatric liver recipients. This is a retrospective analysis of all pediatric patients who underwent liver transplantation at a single liver transplant center in Iran between 1999 and 2006. During this period 72 liver transplantations were performed in children <18 yr. Twenty-two children underwent 33 re-explorations after liver transplantation. Five bowel perforations occurred in four children (incidence, 6.9%). One patient required two re-explorations. The median time between liver transplantation and the diagnosis of the bowel perforation was seven days. All patients had abdominal distention before re-exploration. The sites of perforation were jejunum (n = 3) and ileum (n = 2), and simple repair was performed in all cases. Three children had a history of prior Kasai operation. One of them received high dose of methylprednisolone before bowel perforation. Two children expired after bowel perforation (mortality rate, 50%). Bowel perforation is relatively frequent after pediatric liver transplantation. Among risk factors, prior Kasai operation may have a role. We observed that abdominal distention is a sign of bowel perforation and a high index of suspicion is required for rapidly diagnosis of this complication. The outcome of bowel perforation is poor and its mortality is high. Further studies are needed to establish real risk factors for this complication.