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.     

Histological assessment of bile lake formation after hepatic portoenterostomy for biliary atresia

Bile lakes develop after hepatic portoenterostomy in some patients with biliary atresia, and have been regarded as an indication of poor prognosis. We reported that bile lakes have no epithelium of the bile duct on their wall, and are surrounded by bile ducts; however, the mechanism of bile lake formation is little known. We investigated histologically how bile ducts are formed using whole removed liver, and the characteristics of bile ducts around bile lakes. From April 1980 to July 2006, we encountered 84 patients with biliary atresia. Bile lakes were analyzed histologically in 11 patients who underwent liver transplantation in our hospital. Bile lakes had a fibrotic cyst wall and lacked epithelia. In most cases, bile stasis, calculi formation, damaged bile ducts, and invasion of inflammatory cells were observed around the bile lakes. Bile ducts around bile lakes were not stained by CD56, but bile ducts around liver lobuli were stained by CD56. The present study speculates that bile lakes would arise from original bile ducts, which are damaged, and fuse together after calculi are formed in bile ducts.     

Abnormal activation of OPN inflammation pathway in livers of children with biliary atresia and relationship to hepatic fibrosis

OBJECTIVE: Aim of the study was to investigate the expression of OPN (osteopontin) and its upper-downstream regulating factors in the biliary atretic liver and explore the relationship to progressive intrahepatic fibro-inflammation. METHOD: OPN expression in the livers of 18 children with biliary atresia (BA), 15 children with congenital biliary dilatation (CBD) and 8 normal controls were examined by immunostaining. Masson's trichrome stain was used to evaluate the level of hepatic fibrosis in each group. Western blotting and RT-polymerase chain reaction were respectively used to semiquantitatively analyze the NF-kappaB (nuclear factor-kappaB) and the TGF-beta1mRNA (transforming growth factor-beta1) expression in each group. RESULTS: OPN expression was found in the epithelial cells of the intrahepatic bile duct in the BA group, and its intensity was 0.33 +/- 0.10, while there was only little expression of OPN in the epithelial cells of the intrahepatic bile ducts in the CBD group and normal controls. There was a positive correlation between the intensity of OPN and the level of hepatic fibrosis in BA livers (r = 0.97). The intensity of NF-kappaB expression in BA livers (0.76 +/- 0.07) was much higher than that in CBD livers (0.25 +/- 0.04) or the livers of normal controls (0.22 +/- 0.02). A positive correlation was detected between the intensity of NF-kappaB and OPN in BA livers (r = 0.94). The expression of TGF-beta1mRNA in BA livers (1.46 +/- 0.17) was much higher than that in CBD livers (0.68 +/- 0.11). Little expression of TGF-beta1mRNA was detected in the livers of normal controls. A positive correlation was detected between the expression of TGF-beta1mRNA and the intensity of OPN in BA livers (r = 0.88). CONCLUSION: The abnormal activation of the OPN inflammation pathway might play a key role in the generation of intrahepatic fibrosis in BA. This progressive fibro-inflammation might be controlled by OPN and its upper-downstream regulating factors NF-kappaB and TGF-beta1.     

Coincidental cases of primary sclerosing cholangitis and biliary atresia in siblings?

Familial cases of primary sclerosing cholangitis or biliary atresia have been reported, although genetic influences and immunopathological abnormalities in these diseases are considered to be obscure. We report a case of primary sclerosing cholangitis and biliary atresia in siblings with the observation of HLA-DR antigen expression in the abnormal bile duct epithelial cells.     

The remodeling of the primitive human biliary system

From 12 weeks of gestation on, a progressive remodeling of the human primitive biliary structure or ductal plate occurs. A few parts of the primitive biliary structure (peripheral tubular or ductular structures) dilate, migrate toward the center of the portal tract, and transform into mature bile ducts, while most of them gradually disappear. To the best of our knowledge, quantitative studies have been performed only to evaluate the ratio between the number of remodeled bile ducts and portal tracts during human fetal development. We studied the remodeling of the intrahepatic fetal biliary structures as well as the bile duct to portal tract ratio in the developing human liver by immunohistochemistry with monoclonal antibodies anti-bile duct type cytokeratins and using a computer-based image-analysis system. We found that the surface and the perimeter of the portal tracts, the longest axis of the migrating peripheral tubular structures, and the maturation of bile ducts follow a process continuous and active up to term, but they slow between the 20th and the 32nd week of gestation, when intraportal granulopoiesis of the liver is active.     

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.     

Experimental hepatoportoenterostomy: duct mucosal healing with hybrid biliary-intestinal epithelium forming an autoanastomosis

Permanent bile flow following hepatoportoenterostomy for biliary atresia is presumed to follow mucosal healing of the biliary tract to the intestinal epithelium, but the morphology of the anastomosis and the histology of the neo-biliary duct is not known. Experimental portoenterostomies were constructed in five normal 10-kg mini-pigs at approximately 3 months of age to study the healing of the anastomosis. The extrahepatic bile duct was resected in continuity with an en-bloc 1.5 × 0.3-cm segment of liver at the porta hepatis and biliary drainage was achieved with a Roux-en-Y jejunal limb. The bile duct remnant at the porta hepatis measured 3 mm in diameter. HIDA scan performed at 2 months showed prompt excretion of the radioisotope and normal function of the jejunal limb. Animals were killed at 2 weeks, 1 month, and 3 months following operation and the intact hepatobiliary anastomosis examined by routine histology and histochemical staining for acid and neutral mucins. At 2 weeks the biliary epithelial ducts were hyperplastic and showed evidence of cellular regeneration and cholangitis. By 1 month the biliary and intestinal epithelia were in close approximation. At 3 months the biliary-intestinal epithelium was healed, forming a funnel-like autoanastomosis with normal proximal biliary epithelium and distal intestinal epithelium. An intervening zone of hybrid biliary-intestinal epithelium showed basal crypts with characteristics of biliary epithelium, while the superficial glandular epithelium resembled intestinal villi. Mucin histochemistry of the hybrid epithelial lining revealed predominantly neutral mucins in the basal region of the mucosa characteristic of biliary mucosa. The luminal epithelium revealed a high acid mucin content, including goblet cells. A microvillus brush border, rich in neutral mucin, was also present apically on the luminal most cells. We conclude that: (1) hepatoportoenterostomy in normal mini-pigs is a reproducible model to study healing of the anastomosis; (2) a continuous, intact hepatobiliary-intestinal mucosa is present within 3 months following portoenterostomy; and (3) the neo-epithelium has a hybrid biliary-intestinal appearance. This study may have application to understanding the cause of cholangitis following portoenterostomy for biliary atresia.     

Cytokeratin immunohistochemical examination of liver biopsies in infants with Alagille syndrome and biliary atresia.

Identifying bile duct epithelium is sometimes difficult with standard histologic techniques. The availability of antibodies to specific cytokeratin (CK) intermediate filaments has allowed identification of CK expressed by bile duct epithelium. Formalin-fixed, paraffin-embedded liver tissue from five infants (aged 1-12 months) with Alagille syndrome and five infants with biliary atresia (aged 1.5-11 months) were pepsin digested then reacted with a combination of anti-cytokeratin monoclonal antibodies using an avidin-biotin immunoperoxidase technique. Liver tissue obtained at autopsy from infants without primary liver disease (aged 22 weeks gestation to 24 months) was treated similarly for comparison. Control specimens showed progression from prominent immunoreactivity of the ductal plate cells at the rim of the portal tract (22-24 weeks gestation) to incorporation of tubular ductal structures into portal tract mesenchymal tissue (26-34 weeks gestation) and formation of intensely immunoreactive mature discrete interlobular ducts with progressive loss of cytokeratin immunoreactivity of the ductal plate cells (1-24 months). In contrast, biopsies from infants with Alagille syndrome showed few immunoreactive interlobular ducts. Biopsies from infants with Alagille syndrome less than 2 months old showed only immunoreactivity of single ductal plate cells or small ductules at the periphery of the portal tracts. Biopsies from some infants greater than 3 months old showed increased numbers of immunoreactive cells in groups and anastomosing bands lacking true lumens and extending into the fibrous bridges between adjacent portal areas (neoductular proliferation).(ABSTRACT TRUNCATED AT 250 WORDS)     

Clinical and pathological characteristics of cystic lesions of extrahepatic bile duct in neonates

Aim: To investigate the differences in clinical and pathological manifestations between biliary atresia with extrahepatic biliary cyst and choledochal cyst in neonates. Methods: Symptoms and clinical signs in 5 neonates with biliary atresia with extrahepatic biliary cyst (4 of type I and 1 of type III) and 17 neonates with choledochal cyst were recorded. The levels of serum alkaline phosphatase, bilirubin, direct bilirubin, transaminase, gamma-glutamyl transpeptidase were analysed. Width and length of gallbladder and choledochal cyst were measured on B-mode ultrasound before surgery. Intrahepatic or extrahepatic biliary ducts were visualized with intraoperative cholangiography. The pathologic features in specimens of the liver were studied with light- and electron transmission microscopy. Results: All malformations occurred more commonly in girls, and obstructive jaundice was the main manifestation in both groups. Laboratory tests showed similar results for all patients in this study. With regard to pathological features, no significant difference was seen in either light microscopy or transmission electron microscopy, but it was shown with ultrasound that the length and width of the cysts and the gallbladder in neonates with biliary atresia were all shorter than the measurements in patients with choledochal cyst. The intrahepatic bile ducts could not be visualized on intraoperative cholangiography in type III biliary atresia. Deformation of the biliary ducts within the liver and stricture of the portal bile duct were the predominant features in type I biliary atresia, while the bile duct within the liver was normal or dilated in neonates with choledochal cyst.

Conclusions: Cystic lesions of the extrahepatic bile duct might be a common manifestation of biliary atresia and choledochal cyst. Intraoperative cholangiography is a precise and effective technique in the differential diagnosis of those lesions and helps decide on the most rational method of treatment.     

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.     

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.     

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.     

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.     

胆道闭锁肝内外胆系组织病理形态学分析

目的 通过胆道闭锁（BA）肝门纤维块、肝脏组织的病理及其超微结构观察，对肝门成纤维细胞分化程度进行评分，并与肝纤维化分级进行相关分析。方法 选取BA患儿作为研究对象，术中取肝门纤维块及肝脏组织标本；研究同期选取疑似BA经术中胆道造影除外BA，诊断为胆汁淤积综合征和先天性胆管扩张症患儿作为对照组，留取肝脏组织标本。在光镜和电镜下观察标本的病理改变，以及肝细胞、毛细胆管和肝门成纤维细胞的超微结构。采用SPSS 14.0软件，半定量比较BA与对照组肝脏纤维化的差异，检验肝门纤维块成纤维细胞活跃程度与肝纤维化分级的相关性。结果 2005年7月至2006年5月复旦大学附属儿科医院收治的21例BA Kasai根治术病例，手术平均年龄（66±20）d；对照组为5例胆汁淤积综合征和10例先天性胆管扩张症患儿。BA组肝组织病理改变主要是肝内门脉区胆管炎症及纤维化形成，肝纤维化程度明显高于同年龄胆汁淤积综合征和先天性胆管扩张症患儿；肝门纤维块毛细胆管增生，部分管腔闭锁、狭窄，腔内炎细胞浸润及部分淤胆，大量间质成分增生；电镜下肝门成纤维细胞活跃、肝脏毛细胆管上皮微绒毛缺失、肝细胞及肝血窦内电子致密物质增多及部分毛细胆管扩张；肝门成纤维细胞分化程度与肝组织纤维化程度相关（P=0.04）。结论 BA肝组织病理改变主要是肝内门脉区胆管炎症及严重纤维化形成；超微结构改变提示肝门部成纤维细胞活跃，其分化程度与肝纤维化程度相关。     

γ-谷氨酰转肽酶在胆道闭锁诊断和预后评价中的研究进展

胆道闭锁是小儿外科常见疾病,早期诊断困难,预后差.γ-谷氨酰转肽酶(gamma-glu-tamyltransferase,GGT)是谷胱甘肽代谢的关键酶,广泛存在于人体各组织中,主要位于细胞膜外表面.肝脏中GGT主要分布于肝细胞胞质与肝内胆管上皮细胞中.胆道闭锁引起的胆管系统堵塞会导致过多的GGT在肝脏中不断淤积并进入...     

Bile acids in serum and bile of infants with cholestatic syndromes

The concentration of individual bile acids in serum was measured in 18 neonates and infants with various cholestatic conditions (extrahepatic biliary atresia, neonatal hepatitis syndrome, chronic intrahepatic cholestasis and posthemolytic cholestasis). The cholate/chenodeoxycholate ratio in serum was smaller than one in all patients with neonatal hepatitis syndrome or extrahepatic biliary atresia, cholestatic conditions which were accompanied by signs of liver cell injury. It was greater than one in the patients with chronic intrahepatic cholestasis. Administration of cholestyramine to patients with patent extrahepatic bile ducts decreased the total concentration bile acids in serum and elevated the cholate/chenodeoxycholate ratio. Thus, cholestyramine administration may be of diagnostic value for evaluation of bile duct patency in cholestasis of infancy. Differences between the bile acid pattern in serum and bile were observed. Thus, the cholate/chenodeoxycholate ratio was always higher in bile than in serum. 3beta-hydroxy-5-cholenoic acid found in serum was not detectable in bile. This finding suggests that impairment of biliary excretion rather than increased hepatic synthesis is responsible for elevation of this monohydroxy bile acid in serum.     

EpCAM阳性的不成熟胆道上皮细胞促进胆道闭锁肝纤维化的研究

目的 分析在胆道闭锁患儿肝组织中增生的EpCAM阳性的不成熟胆道上皮细胞与肝纤维化形成的关系,从而探讨不成熟的胆道上皮细胞在胆道闭锁病程进展中的作用.方法 选取2012年1月至2015年6月于我院就治的患儿肝石蜡标本进行连续切片,其中胆道闭锁(biliary atresia,BA) 65例,胆总管囊肿(choledochal cyst,CC) 27例,门静脉海绵样病变(cavernous transformation of portal vein,CTPV) 15例,应用CK19、EpCAM免疫组织化学染色及饱和苦味酸天狼星红染色方法,分析肝组织中增生的胆道上皮细胞的成熟性、EpCAM阳性的不成熟胆道上皮细胞与肝纤维化在位置上的关系,并应用Image-pro对400倍视野下肝组织切片中EpCAM阳性细胞进行计数,观察其增生数量与肝纤维化分级间的关系.结果 在CTPV组可见由CK19阳性的胆道上皮细胞组成的正常成熟的胆管,未见明显增生的胆道上皮细胞.在BA组及有纤维化的CC组可见胆道上皮细胞增生明显,邻近肝纤维化部位的胆道上皮细胞主要为EpCAM阳性的不成熟胆道上皮细胞,与肝纤维化存在位置上的关联.在胆道闭锁肝组织中随着肝纤维化的程度越高,EpCAM阳性的不成熟胆道上皮细胞的数量越多,且不同肝纤维化分期中EpCAM阳性细胞增生的数量存在显著差异(r=0.56,P＜0.001).结论 在小儿胆道闭锁疾病中,EpCAM阳性的不成熟胆道上皮细胞在短时间内迅速增生,可能是胆道闭锁患儿肝纤维化进展迅速的主要原因.     

Portal vein phlebolithiasis found post-liver transplantation in the native liver of a child with biliary atresia

Biliary atresia is defined as partial or total obliteration of the extra-hepatic bile ducts. In advanced cases, liver transplantation (LTx) is considered the most appropriate treatment. This report describes a female patient whose biliary atresia and subsequent cirrhosis required LTx at 1 yr of age. Macroscopic inspection of the hilar region of the native liver post-Tx revealed the formation of a pouch in the hepatic duct and a stone in the lumen of the portal vein. X-ray diffraction analysis showed that the stone was composed of cholesteryl cinnamate, gluconic acid phenylhydrazide, Na beta broma-allyl mercaptomethyl penicillinate, and Al2O3 crystals. While the cholesterol component is a known element of gallstones, we attributed the Na beta broma-allyl mercaptomethyl penicillinate to the patient's drug therapy. Our literature search revealed no previous record or crystallographic analysis of portal vein phlebolithiasis. In this report we describe this rare finding.