Expression of osteopontin correlates with portal biliary proliferation and fibrosis in biliary atresia

The acquired or perinatal form of biliary atresia is a Th1 fibro-inflammatory disease affecting both the extrahepatic and intrahepatic bile ducts. Osteopontin (OPN) is a Th1 cytokine implicated in several fibro-inflammatory and autoimmune diseases. We examined the expression of OPN in acquired biliary atresia in comparison to normal liver and several pediatric cholestatic liver diseases. We also assessed OPN expression by cultured human bile duct epithelial cells. We found that liver OPN mRNA and protein expression were significantly increased in biliary atresia versus normal and other cholestatic diseases. OPN expression in biliary atresia was localized to epithelium of proliferating biliary structures (ductules and/or ducts) and bile plugs contained therein. No portal biliary OPN expression could be demonstrated in normal liver, syndromic biliary atresia, biliary obstruction not due to biliary atresia, and idiopathic neonatal hepatitis. OPN expression by human bile duct epithelial cells in culture was responsive to IL-2 and TNF-alpha. Our results demonstrate an up-regulation of OPN expression by interlobular biliary epithelium in biliary atresia, which correlates with biliary proliferation and portal fibrosis. These findings suggest a role for OPN in the pathogenesis of biliary atresia.     

Type I biliary atresia without extrahepatic biliary cyst

Currently, magnetic resonance cholangiography (MRC) is used for the differentiation of biliary atresia (BA) from other causes of infantile cholestasis. The authors present a case of type I BA without an extrahepatic biliary cyst in a 2-month-old girl. MRC clearly visualized the patency of the gallbladder, cystic duct, and hepatic ducts with disappearance of the common bile duct. Intraoperative cholangiography demonstrated a cloudy appearance of the intrahepatic bile ducts, confirming the diagnosis of type I BA. We believe that this is the first reported case of type I BA without an extrahepatic biliary cyst diagnosed by MRC.     

Biliary atresia: cellular dynamics and immune dysregulation

The cause of biliary atresia is unknown; in the past few decades, the majority of investigations related to its pathogenesis have centered on viral infections and immunity. The acquired or perinatal form of biliary atresia entails a progressive inflammatory injury of bile ducts, leading to fibrosis and obliteration of both the extrahepatic and intrahepatic bile ducts. Theories of pathogenesis include viral infection, chronic inflammatory or autoimmune-mediated bile duct injury, and abnormalities in bile duct development. This review will focus solely on human studies pertaining to a potential viral trigger of bile duct injury at diagnosis and provide insight into the interplay of the innate and adaptive immune responses in the pathogenesis of disease.     

Evolving biliary atresia with cytomegalovirus

Multiple studies have been conducted to demonstrate the role of viruses in causing biliary atresia. Although cytomegalovirus (CMV) is known to cause intrahepatic bile duct destruction, its role in biliary atresia is not proven. We report two cases of CMV infection, initially presenting with intrahepatic cholestasis, who subsequently developed biliary atresia.     

Significance of the anomalous arrangement of the pancreaticobiliary duct in the etiology of biliary atresia.

BACKGROUND/PURPOSE: The anomalous arrangement of the pancreaticobiliary duct (AAPBD) is one theory used to explain the etiology of biliary atresia. We investigated whether AAPBD could be involved and evaluated its significance for the etiology of biliary atresia. MATERIALS AND METHODS: Of 43 patients with biliary atresia, the area between the common bile duct and the duodenum could be visualized by operative cholangiogram in 5 patients with an uncorrectable type of biliary atresia. Three of the 5 showed an anomalous arrangement of the pancreaticobiliary duct. In these 3 patients, the type of anomalous arrangement of the pancreaticobiliary duct and the length of the common channel were studied by operative cholangiogram. Histological findings of the gallbladder and the common bile duct were examined in addition to the measurement of the serum amylase levels. RESULTS: All 3 patients showed AAPBD with the P-C type of pancreaticobiliary junction. The length of the common channel ranged from 7 mm to 12 mm. Two of the 3 cases did not show an elevated serum amylase level. Epithelial hyperplasia of the gallbladder was observed in one patient, while the other two showed no hyperplasia. Inflammatory changes in the mucosa of the gallbladder and the common bile duct were not remarkable in these 3 patients. CONCLUSIONS: From these results it seems that AAPBD in biliary atresia might not be an etiological factor for atresia of the extrahepatic bile duct, but might be an associated anomaly in biliary atresia. Other factors should be examined to clarify the etiological factor leading to lumenal obstruction of the extrahepatic bile duct.     

Atypical morphologic presentation of biliary atresia and value of serial liver biopsies

BACKGROUND: Liver biopsy findings are important in diagnosing extrahepatic biliary atresia. Diffuse ductular proliferation is a characteristic finding. We describe four patients with conjugated hyperbilirubinemia in whom the initial liver biopsy findings showed a lack of ductular proliferation, despite subsequent development of biliary atresia. RESULTS: On initial biopsy, paucity of intrahepatic bile ducts was present in three of four patients, with a bile duct to portal space ratio of 0.3 to 0.4 (normal, 0.9-1.8). A normal bile duct to portal space ratio of 1.0 was observed in the fourth patient. Ductular proliferation became apparent in three subjects between 9 and 12 weeks of age, and biliary atresia was noted at the time of a Kasai portoenterostomy. The fourth child had well-developed biliary cirrhosis at liver transplantation. CONCLUSIONS: Changes characteristic of biliary atresia may appear even after 9 weeks of age. Bile duct paucity and normal bile duct to portal space ratio do not preclude the subsequent development of biliary atresia. Infants with unexplained conjugated hyperbilirubinemia and acholic stools should undergo sequential liver biopsies until clinical improvement occurs or until biliary atresia can be excluded from the differential diagnosis.     

The role of reovirus type 3 infection in an established murine model for biliary atresia.

AIM OF THE STUDY: Infection of newborn Balb/c-mice with Rhesus rotavirus (RRV) leads to cholestasis and biliary atresia. In this current model, Reovirus Type 3 was investigated to ascertain whether Reovirus Type 3 causes the same or similar hepatobiliary lesions as RRV. METHODS: Newborn Balb/c-mice were infected with Reovirus Type 3 Dearing and Reovirus Type 3 Abney on the first day of life. Clinical observation followed for a period of at least 10 days. Cholestatic and/or dystrophic mice were prepared and specimens were taken for histological examination. RESULTS: Infection with RRV showed a 85 % morbidity for biliary atresia as described before. Clinical disease, following an infection with Reovirus T3 Dearing, showed neurological symptoms such as ataxia, and all mice died within 3 weeks. No obstructive or atretic changes of the hepatobiliary ducts could be seen either macroscopically or histomorphologically. 60 % of the mice having been infected with Reovirus T3 Abney showed signs of cholestasis and oily fur syndrome, but almost 15 % recovered from the disease. Although the histological findings did not reveal biliary atresia, inflammation and destruction of bile ducts could be observed. CONCLUSION: In comparison to the RRV infection in a Balb/c-mice model, where biliary atresia could be induced, infection with Reovirus T3 in this model did not lead to biliary atresia. But Reovirus T3 Abney infection revealed inflammatory signs as described in the literature before. The question as to why different hepatotrophic viruses lead to different changes in the murine hepatobiliary tract has to be investigated in further studies.     

The use of ultrasonography in the diagnosis of biliary atresia

Preoperative upper abdominal ultrasonograms of babies with biliary atresia were reviewed in order to determine the efficacy of this technique in the differential diagnosis of biliary atresia and neonatal hepatitis. In 4 patients with neonatal hepatitis and 8 normal controls, ultrasonograms showed echoes of the gallbladder. In 14 patients with biliary atresia, echoes of the gallbladder were not apparent. It is concluded that preoperative ultrasonograms provide an efficient diagnostic method for differentiating biliary atresia from neonatal hepatitis.Offprint requests to: T. Okasora     

Apparent gut excretion of Tc-99m-DISIDA in a case of extrahepatic biliary atresia

Our patient had DISIDA scan at 39 days of age to exclude biliary atresia. Gut excretion was seen 18h after injection and the diagnosis of neonatal hepatitis was made. Because of continued elevated liver function values, liver biopsy was performed and demonstrated findings consistent with biliary atresia. Exploratory laparotomy performed 8 days after the scan showed patent cystic duct, bile duct, and gall-bladder, but an atretic common hepatic duct. This case is an example of documented biliary atresia demonstrating gut excretion on the DISIDA scan.     

Time course of the intrahepatic lesion of extrahepatic biliary atresia: a morphometric study

The time course of the intrahepatic lesions of untreated extrahepatic biliary atresia was evaluated by morphometric analysis of 49 specimens from 27 patients. The data show an early phase of rapid bile ductular proliferation, with peak in this material at 205 days, followed by rapid duct regression to approximately 400 days, and slower progressive intrahepatic duct loss thereafter. The ratio of ducts to connective tissue in portal tracts follows a similar course. Connective tissue in portal tracts rises on a slower course and continues to increase after maximum duct regression is reached, so the ratio of parenchyma to fibrous septa falls over the later course of the process. Although duct and connective tissue proliferation in hepatic portal tracts is associated in many liver diseases, the data of this study demonstrate dissociability of the relationships, with the fibrosis in the later stages of the intrahepatic process in extrahepatic biliary atresia apparently neither responsive to nor inducing biliary ductular proliferation.     

Hazards of hepatic portocholecystostomy in biliary atresia.

A hepatic portocholecystostomy (HPC) has been recommended to avoid postoperative cholangitis in the case of a patent distal extrahepatic bile duct (PDEBD) for the treatment of biliary atresia (BA). We investigated the efficacy and clinical problems of HPC in BA. The clinical records of eight patients with BA and PDEBD were reviewed. The diameter of the common bile duct was compared between the patients with BA and PDEBD and age-matched patients with neonatal hepatitis (NH). Five of 8 patients with PDEBD underwent HPC. One patient had to be converted to a cholecystojejunostomy because of common bile duct stenosis at 19 years of age. The other two patients underwent a reoperation by a hepatic portojejunostomy due to poor bile drainage after HPC. Another patient became jaundice-free one month after HPC, but died of sepsis due to bile leakage 3 months thereafter. The mean diameter of the common bile duct in BA with PDEBD was significantly smaller than that of NH (0.76 +/- 0.16 mm (n = 8) in BA vs. 1.90 +/- 0.39 mm (n = 11) in NH, p<0.01). HPC was thus found to be an excellent operative method for preventing postoperative cholangitis in BA, however, many clinical problems still need to be overcome for such a narrow distal duct.     

胆道闭锁Kasai术后糖皮质激素治疗的研究进展

胆道闭锁是累及肝内外胆管的一种进行性疾病,目前广泛采用的治疗策略是行肝门-空肠吻合术(Kasai手术),术后辅以包括糖皮质激素、抗生素等多种药物治疗,然而糖皮质激素在胆道闭锁的治疗中争议较多,其应用方案也多种多样,现将糖皮质激素在胆道闭锁Kasai术后的应用进展进行综述。     

Yellow is pale: The complications and challenges of late diagnosis of extrahepatic biliary atresia

Extrahepatic biliary atresia classically presents in the neonatal period with jaundice and pale stools. The lack of bile pigment in stool can be unrecognised, delaying diagnosis and surgical treatment. Vitamin K is given at birth to reduce the risk of haemorrhagic disease of the newborn, but this may be inadequate to prevent the development of coagulopathy secondary to fat soluble vitamin malabsorption. We present the case of a 3 month old infant who presented with an intracerebral haemorrhage and coagulopathy thought to be secondary to fat malabsorption resulting from delayed diagnosis of extrahepatic biliary atresia. This was despite the perinatal administration of intramuscular vitamin K. His parents did not recognise the stool pallor as being abnormal. This case illustrates the importance of educating parents on the significance of pale stools, and also the risk of coagulopathy in extrahepatic biliary atresia despite perinatal intramuscular vitamin K.     

Intrahepatic biliary tract abnormalities in children with corrected extrahepatic biliary atresia

Three children with surgically corrected extrahepatic biliary atresia developed recurrent cholangitis associated with bile lakes that failed to drain via the hepatoportoenterostomy. Surgical or percutaneous drainage of these cysts was followed by both resolution of the infection and spontaneous internal drainage. We postulate that the ongoing inflammatory process resulted in intrahepatic biliary obstruction, which caused cholangitis and bile cysts. Successful treatment required not only antibiotics but drainage of the bile lakes. Development of bile cysts is a new cause of recurrent cholangitis seen in extrahepatic biliary atresia.     

胆道闭锁患儿肝组织细胞因子及相关基因表达的研究

目的 研究胆道闭锁(BA)患儿肝脏组织中上皮-间充质转化过程中特异性细胞因子的表达及胚胎期发育相关基因的表达激活.旨在探讨BA肝脏纤维化等系列改变的分子机制.方法 取经手术证实为BA患儿的8例肝活检组织(年龄2～3个月),以无消化道疾病尸检婴儿8例肝脏组织做正常对照(年龄0～2个月),RT-PCR半定量法检测胆管上皮细胞特异性因子CK19,纤维化早期指标Ⅰ型胶原蛋白COL1A1,发育相关基因Notch基因受体HES1,TGF-β及其阳性信号分子Smad3的表达水平变化.结果 BA患儿肝脏组织中CK-19,COL1A1、HES1、TGF-β及Smad3等基因表达水平均明显提高,实验组及对照组差异显著.结论 BA患儿肝脏组织胶原组织增生,同时有胆管上皮细胞增生,胚胎期肝脏组织发育相关基因Notch信号通路系统重新激活,TGF-β及其阳性信号分子Smad3在这一过程中发挥作用.     

胆道闭锁与上皮间质转化机制的研究进展

胆道闭锁是危及婴幼儿生命的肝胆系统疾病,以肝内外胆管进行性炎症和纤维化为特征,导致胆汁淤积以及进行性肝纤维化和肝硬化,最终进展为肝功能衰竭,是婴幼儿时期肝移植的主要指征.Kasai手术的广泛开展,使胆道闭锁患儿获得更多的生存机会,但术后60％的患儿1年内需行肝移植,只有25％的患儿自体肝存活至10岁.证据表明上皮间质转化在胆管纤维化中扮演着非常重要的角色,并且TGF-β1表达增强与胆道闭锁发生具有一定的相关性;而肝细胞生长因子(HGF)可明显抑制纤维化促进因子TGF-β1的表达,从而抑制组织纤维化.本文就胆道闭锁可能的发病机制、上皮间质转化在组织纤维化中的作用、针对上皮间质转化的抗纤维化治疗以及胆道闭锁治疗方法的展望作一综述.     

Hepatic calcification in an anicteric patient with biliary atresia after hepatic portoenterostomy

Hepatic calcification was found in an anicteric infant with biliary atresia after hepatic portoenterostomy. When she was 2 years of age, ultrasonography detected an echogenic structure with acoustic shadowing. Computerized tomography located it at the proximal portion of Segment 6 in the right lobe. Although both techniques failed to exhibit dilatation of the peripheral bile ducts, we believe intrahepatic cholelithiasis provides the most likely diagnosis. Although seven cases with biliary atresia were reported to have this complication, all of them were icteric when the diagnosis was confirmed. The patient should be carefully followed up since the succeeding stones may cause jaundice by obstructing the main duct.     

Type-I but not type-II interferon receptor knockout mice are susceptible to biliary atresia

The etiology of biliary atresia (BA) is not yet understood, but recent studies have shown inflammation with an up-regulated interferon (IFN) activity in the intra- and extrahepatic bile ducts of patients with BA. These findings support an inflammatory/infectious cause of BA as mimicked in our infective murine model. To study the role of the IFN receptors in our model, we used mice with inactivated INF-alpha/beta receptor A129, with inactivated IFN-gamma receptor G129, or inactivation of both interferon receptors AG129 as well as the wild type controls W129. Mice were infected with rotavirus within 48h of birth and 7 d postpartum. The incidence of BA in each group was determined during a 3 wk period. In the second week the virus load was measured. BA incidence was 76% in A129 and 67% in AG129 animals, whereas in the G129 group only 33% of the pups developed BA. The wild type presented with a BA-incidence of 15%, while 7 d old mice failed to develop BA. There was no significant difference in the virus load of the livers between the groups independent of clinical symptoms. In conclusion, inactivation of type I INF-receptor significantly increases the incidence of BA following postpartal rotavirus infection. This effect is independent of the presence of type II-INF-receptors. Thus, in our model a type I IFN-linked deregulation of the innate immune system appears to be crucial for the induction of biliary atresia.     

Serial ultrasonic examination to differentiate biliary atresia from neonatal hepatitis — special reference to changes in size of the gallbladder

We performed serial ultrasonic examinations to differentiate biliary atresia from neonatal hepatitis. The subjects studied were 144 children (100 normal neonates and infants, 31 patients with neonatal hepatitis and 13 patients with biliary atresia). They were examined by ultrasound before, during and after feeding. In 97 out of 100 normal children and all patients with neonatal hepatitis, the gallbladder was identified, and the change in size following oral feeding was observed. In four children with severe neonatal hepatitis which could not be differentiated from biliary atresia by clinical and laboratory data, we readily identified the gallbladder and observed the change in the size following oral feeding. In 8 of 13 patients with biliary atresia, we identified a small gallbladder whose size was not affected by oral feeding. In the other patients the gallbladder was not identified before, during or after oral feeding. On the basis of these results, we consider that serial ultrasonic examination with oral feeding aids in a differential diagnosis of biliary atresia and neonatal hepatits.