BILIARY TRACT ANOMALIES—The Utilization of Modern Techniques in Differential Diagnosis

The diagnostic aids used in dealing with biliary disease in adults were applied to the study in infants of the principal congenital anomalies of the biliary tract such as choledochal cyst, biliary atresia and biliary stenosis.Choledochal cysts were distinguished from other upper abdominal masses occurring in childhood by the use of intravenous cholecystography.Since the clinical manifestations in infants with biliary atresia or stenosis are almost identical to those associated with the obstructive phase of neonatal hepatitis, the problem of differentiation is difficult. The serial total serum bilirubin curve, a careful analysis of the pigment content of feces and urine and duodenal intubation for bilirubin determinations were found to be useful in making the distinction. Operative cholangiograms were helpful in some cases. Frozen section examinations of liver tissue during operation were of little value except to demonstrate certain unusual cases of intrahepatic biliary atresia. Routine liver function studies, including serum transaminase determination in a limited number of cases, did not help in differentiation.     

The Diagnostic Value of Serum Leucine Aminopeptidase

Experience with serum leucine aminopeptidase determination in 61 patients led to the following conclusions. The test is no more sensitive than the alkaline phosphatase test in cases of carcinoma of the pancreas. It is elevated in all cases of obstructive and hepatogenous jaundice and serves no useful function in their differentiation. It was a valuable test in cases of calculous biliary tract disease, being more sensitive than either bilirubin or alkaline phosphatase determinations. In three instances of elevated leucine aminopeptidase in disorders apparently not related to the liver or pancreas, laparotomy and autopsy showed involvement of these organs in two.     

Hepatic function following portoenterostomy for extrahepatic biliary atresia.

Liver structure and function in 10 patients with extrahepatic biliary atresia were studied after portoenteric anastomosis (Kasai operation). Bile flow adequate to reduce the serum bilirubin concentration was established in five patients (improved group), three of whom became anicteric. The serum bilirubin concentration did not decrease in the remaining five patients (unimproved group). Hepatic effluent collected postoperatively from both groups contained small amounts of cholesterol and bilirubin; bile salts, however, were present in the hepatic effluent of only the improved patients. Liver biopsy specimens obtained postoperatively from the five improved patients showed partial (in two) or complete (in three) relief of cholestasis; hepatic fibrosis, however, was unchanged (in one) or worse (in four). The serum concentrations of bile salts were markedly elevated, despite normal excretion of sodium sulfobromophthalein and rose bengal, in two anicteric patients studied 14 and 24 months postoperatively. It is concluded that neither structure nor function of the liver is normalized by portoenterostomy even in clinically well, anicteric patients.     

Interleukin-33 overexpression is associated with gamma-glutamyl transferase in biliary atresia

Interleukin-33 (IL-33) plays a crucial role in inflammation. However, it is not clear whether IL-33 levels are of clinical significance for patients with biliary atresia (BA). The purpose of this study was to determine correlations between serum IL-33 levels and the clinicopathologic features of BA. Serum samples were collected from 18 BA infants, 12 nonicteric choledochal cyst (CC) infants with normal liver function, and 10 healthy controls (HCs). Serum IL-33 levels were measured with an enzyme-linked immunosorbent assay (ELISA). Routine liver function tests were performed on the serum samples. qRT-PCR and Western blot analysis were used to detect IL-33 expression in BA liver biopsy tissues. Hepatic lobule localization of IL-33 expression in the hepatic lobule was conducted by immunohistochemistry (IHC). IL-33 levels in serum collected from BA infants were significantly elevated in comparison with CC and HC patients. Furthermore, the elevated serum levels of IL-33 in BA infants were correlated with gamma-glutamyl transferase (GGT) levels. The expression of IL-33 mRNA and protein levels were up-regulated in BA liver biopsy tissues in comparison with CC patients. IHC analysis revealed increased positive immunostaining for IL-33 in BA liver tissues as compared to that in CC tissues. These results suggest that IL-33 may play an important role in the pathogenesis of BA. In addition, the correlation of serum IL-33 levels with GGT levels may provide a novel marker for the diagnosis of BA.     

Identification of HSP90 as Potential Biomarker of Biliary Atresia Using Two-Dimensional Electrophoresis and Mass Spectrometry

Biliary atresia (BA) is a devastating cholestatic liver disease targeting infants. Current diagnosis depends on surgical exploration of the biliary tree. The aim of the present study was to identify potential biomarkers for the diagnosis of biliary atresia (BA). Two-dimensional electrophoresis was utilized for the identification of proteins that were differentially expressed in liver biopsies of 20 BA patients and 12 infants with non-BA neonatal cholestasis (NC) as controls. Using mass spectrometry, we identified 15 proteins with expressions significantly altered. Out of the 15 proteins identified, heat shock protein (HSP) 90 was the most significantly altered and was down-regulated in BA samples compared to NC samples using immunoblotting analysis. Our findings suggest that HSP90 might be a potential biomarker for the diagnosis of BA and may be used for monitoring further development and therapy for BA. This study demonstrated that a comprehensive strategy of proteomic identification combined with further validation should be adopted in biomarker discovery.     

Effect of rotavirus strain on the murine model of biliary atresia

Biliary atresia is a devastating disorder of the newborn in which afflicted infants develop inflammation and fibrosis of the extrahepatic biliary tract, resulting in cirrhosis and end-stage liver disease. Infection with a virus is thought to be a contributing factor in the etiology of biliary atresia. In the murine model of biliary atresia, perinatal exposure to rhesus rotavirus (RRV) results in biliary epithelial cell infection causing bile duct obstruction. The purpose of this study was to determine if tropism for the biliary epithelial cell was unique to RRV. Newborn mice underwent intraperitoneal injection with five strains of rotavirus: RRV (simian), SA11-FM (simian/bovine), SA11-SM (simian), EDIM (murine), and Wa (human). RRV and SA11-FM caused clinical manifestations of bile duct obstruction and high mortality. SA11-SM caused clinical signs of hepatobiliary injury but the mortality was markedly reduced. EDIM and Wa caused no sign of hepatobiliary disease. The systemic and temporal distribution of viral protein and live virus varied according to the injected strain. Immunohistochemistry revealed that RRV and SA11-FM targeted the biliary epithelial cells. In contrast, SA11-SM was found in the liver but in not in the biliary epithelium. These results indicate that strain-specific characteristics dictate tropism for cells of hepatobiliary origin which in turn impact the ability to induce the murine model of biliary atresia.     

Results of surgical treatment for extrahepatic biliary atresia in United Kingdom 1980-2. Survey conducted on behalf of the British Paediatric Association Gastroenterology Group and the British Association of Paediatric Surgeons.

A postal survey identified 114 infants with biliary atresia (roughly one in 21 000 live births). Biliary operations were performed on 107. Of the 105 infants who were followed up, 35 were free of jaundice at 10 months to 3 1/2 years. Good results occurred most often in those operated on by 12 weeks and were also related to the number of cases operated on in each centre. Only two of 18 infants treated in centres dealing with one case a year were free of jaundice compared with 11 of 38 at centres treating two to five cases a year and 22 of 49 in a centre treating more than five cases a year. Jaundice in an infant of more than 2 weeks associated with yellow urine or pale stools is never physiological and requires urgent investigation to identify causes for which effective treatment may be possible. Identification of suspected cases by 4 weeks of age and a greater concentration of investigative and surgical skills should improve the short term results of surgery and the long term prognosis of biliary atresia.     

胆道闭锁患儿血清GPC3、TGF-β1和VEGF水平与肝硬度值和肝功能的关系研究

目的:研究胆道闭锁(BA)患儿血清磷脂酰肌醇蛋白聚糖3(GPC3)、转化生子因子β1(TGF-β1)和血管内皮生长因子(VEGF)水平与肝硬度值和肝功能的关系。方法:选择2016月3月-2019年3月期间在我院接受Kasai手术治疗的62例BA患儿作为研究对象(BA组),并根据总胆红素水平分为黄疸患儿(总胆红素≥34.2μmol/L)、无黄疸患儿(总胆红素<34.2μmol/L);另取同期在本院体检的50例健康儿童作为对照组。检测BA组患儿术后2个月、对照组儿童体检时的血清GPC3、TGF-β1、VEGF及肝功能指标白蛋白(ALB)、丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、γ-谷氨酰转肽酶(GGT)的水平及肝硬度值,采用Pearson相关分析血清GPC3、TGF-β1和VEGF水平与肝硬度值和肝功能的相关性。结果:BA组患儿的血清GPC3、TGF-β1、VEGF、ALT、AST、GGT水平及肝硬度值均明显高于对照组(P<0.05),血清ALB水平与对照组比较无统计学差异(P>0.05);BA组中黄疸患儿的血清GPC3、TGF-β1、VEGF、ALT、AST、GGT水平及肝硬度值均明显高于无黄疸患儿,血清ALB水平明显低于无黄疸患儿(P<0.05);BA组中血清GPC3、TGF-β1、VEGF水平与血清ALT、AST、GGT水平及肝硬度值呈正相关(P<0.05),与血清ALB水平呈负相关(P<0.05)。结论:BA患儿术后GPC3、TGF-β1和VEGF的升高与肝纤维化进程、肝功能破坏有关,未来可能成为研究BA术后肝纤维化发生机制的靶点。     

Measurement of changes in amino acids related to total collagen in fibrotic human liver

In the liver, total collagen accumulation during the fibrotic or cirrhotic process was measured using a methodology based on the determination of collagen amino acids in liver biopsies from adults with alcoholic liver diseases or children with biliary atresia. The results obtained with this methodology were compared to histopathological findings. Thus, it was shown that generally the severity of hepatic injury was dependent on collagen accumulation. In biliary atresia, collagen accumulation increased with the children's age despite reconstructive surgery and restoration of biliary flow.     

Bilirubin excretion into bile after partial hepatectomy in rats

Biliary excretion of bilirubin was studied in Wistar rats at different intervals following two-thirds hepatectomy. Endogenous bilirubin excretion was not significantly modified during liver regeneration. The maximal biliary excretion rate (Tm) of bilirubin, expressed per 100 g of body weight, significantly decreased immediately after hepatectomy with a recovery to presurgery values by 16 days. Values expressed per g of liver were significantly lowered only by 12- and 24h posthepatectomy. In these early periods there was a significant increase in the liver concentration of unconjugated bilirubin and a decrease in bile flow following bile pigment infusion. Maximal excretion of bilirubin in the rat seems to change parallel to the regeneration of liver mass except during the first 24h in which the inhibitory effects exerted by the high load of exogenous bilirubin would cause a decline in its own biliary output with an added cholestatic effect.     

Genetic variability of interleukin4 gene in Taiwanese children with biliary atresia

Biliary atresia (BA) is a neonatal cholangiopathy of unknown etiology that leads to biliary cirrhosis and is the most common cause of liver transplantation in children. A still undetermined hepatobiliary viral infection may elicit an uncontrollable autoimmune response against the biliary epithelial cells in genetically predisposed children and culminates in atresia of the biliary trees. Interleukin 4 (IL4) is crucial for the differentiation of naive T helper cells into the T helper 2 effector cells that promote humoral immunity. This study aims to investigate whether polymorphisms of the IL4 gene are associated with susceptibility to BA. Genomic DNA was extracted from whole blood samples of 53 Taiwanese children with BA and 904 ethnically-matched healthy controls. The IL4 -590 C/T, -33 C/T, and 8375 A/G polymorphisms were genotyped using the Pre-Developed TaqMan Allelic Discrimination Assay in a real-time polymerase chain reaction system. No significant difference between children with BA and healthy controls were found when comparing genotype, allele, carrier, and haplotype frequencies of these IL4 gene variants. These results suggest that the tested polymorphisms of IL4 gene are unlikely to contribute significantly to BA susceptibility in Taiwanese children.     

Alagille Syndrome Mimicking Biliary Atresia in Early Infancy

Alagille syndrome may mimic biliary atresia in early infancy. Since mutations in JAG1 typical for Alagille syndrome type 1 have also been found in biliary atresia, we aimed to identify JAG1 mutations in newborns with proven biliary atresia (n = 72). Five biliary atresia patients with cholestasis, one additional characteristic feature of Alagille syndrome and ambiguous liver histology were single heterozygotes for nonsense or frameshift mutations in JAG1. No mutations were found in the remaining 67 patients. All “biliary atresia” carriers of JAG1 null mutations developed typical Alagille syndrome at the age of three years. Our data do not support association of biliary atresia with JAG1 mutations, at least in Czech patients. Rapid testing for JAG1 mutations could prevent misdiagnosis of Alagille syndrome in early infancy and improve their outcome.     

Extrahepatic biliary atresia with laterality sequence anomalies

The patient was the first child of first cousin parents. He was born at term after an uneventful pregnancy with normal height, weight and head circumference. Jaundice appeared at 15 days of age. Ventricular septal defects and valvular pulmonary stenosis were diagnosed. An hepatic workup revealed extrahepatic biliary atresia and abdominal situs inversus. Hepatic biopsy showed cirrhosis with intrahepatic cholestasis. Genetic factors are suggested in extrahepatic biliary atresia. Analysis of segregation patterns suggested the existence of two major groups, one with various combinations of anomalies within the laterality sequence and the other with one or two anomalies mostly involving the cardiac, gastrointestinal, and urinary systems. This patient belongs to the first group.     

A New Clarification Method to Visualize Biliary Degeneration During Liver Metamorphosis in Sea Lamprey (Petromyzon marinus)

Biliary atresia is a rare disease of infancy, with an estimated 1 in 15,000 frequency in the southeast United States, but more common in East Asian countries, with a reported frequency of 1 in 5,000 in Taiwan. Although much is known about the management of biliary atresia, its pathogenesis is still elusive. The sea lamprey (Petromyzon marinus) provides a unique opportunity to examine the mechanism and progression of biliary degeneration. Sea lamprey develop through three distinct life stages: larval, parasitic, and adult. During the transition from larvae to parasitic juvenile, sea lamprey undergo metamorphosis with dramatic reorganization and remodeling in external morphology and internal organs. In the liver, the entire biliary system is lost, including the gall bladder and the biliary tree. A newly-developed method called “CLARITY” was modified to clarify the entire liver and the junction with the intestine in metamorphic sea lamprey. The process of biliary degeneration was visualized and discerned during sea lamprey metamorphosis by using laser scanning confocal microscopy. This method provides a powerful tool to study biliary atresia in a unique animal model.     

胆总管内注射无水乙醇致胆道闭锁动物模型的建立

目的应用胆总管内注射无水乙醇建立SD大鼠胆道闭锁模型。方法将SD雄性大鼠随机分为实验组和对照组,在实验组中经静脉留置针插入胆总管注入无水乙醇,对照组注入生理盐水。观察SD大鼠的生化及病理结果。结果在实验组中SD大鼠根据病理及生化检测分为肝功能持续恶化组和肝功能修复组,肝功能持续恶化组在8周以后生化明显高于对照组及肝功能修复组。常规HE染色及SMA、Masson染色也出现明显变化。结论胆总管无水乙醇注射诱导胆道闭锁模型是一种可靠的动物模型,此动物模型会帮助人们进一步研究胆道闭锁提供更多的研究手段。     

早期光疗对早产儿黄疸的影响

目的：探讨在经皮胆红素监测下早期蓝光干预对早产儿高胆红素血症的防治作用。方法：选择2009年10月-2011年10月我院新生儿科收治的86例出生体重≤2000g,无出生窒息史的早产儿,按住院号单双号分为观察组46例和对照组40例。对照组按照我国2000年制定的新生儿黄疸干预推荐方案的干预标准进行光疗。观察组于出现黄疸和／或经皮胆红素〉85．50μmol／L,但尚未达方案的干预标准就进行光疗,监测经皮胆红素至黄痘消失。经皮胆红素值达187．5μmol／L以上时同时查静脉血监测血清总胆红素。比较2组早产儿经皮胆红素峰值及恢复正常时间。结果：观察组与对照组比较经皮胆红素峰值较低,黄疸持续时间较短,两组比较P均〈0．05,有统计学差异。结论：早产儿在经皮胆红素监测下进行早期蓝光干预有利于降低早产儿胆红素峰值,缩短黄疸持续时间。有效预防早产儿胆红素脑病。     

Gap junctions and zonulae occludentes of hepatocytes during biliary atresia in the lamprey

Gap junctions and zonulae occludentes of hepatocytes were examined in thin sections and freeze-fracture replicas from livers of larval and juvenile adult lampreys and during the phase of metamorphosis when bile ducts and bile canaliculi disappear (biliary atresia). Larvae possess zonulae occludentes at the canaliculi which are composed of one to five (mean = 2.81) junctional strands that provide a bile-blood barrier. Morphometry demonstrates that during biliary atresia the decreases in number of junctional strands and apico-basal depth of the zonulae occludentes are accompanied by an increase in the frequency of gaps or interruptions in the strands and in a breakdown of the bile-blood barrier. The zonulae occludentes completely disappear during metamorphosis and are not found in the adult liver. Gap junctions of the larval liver occupy 1% of the surface of the plasma membrane and have a mean area of 0.167 micron 2 but, following an initial decline in these parameters during early biliary atresia, they rise sharply in later stages of metamorphosis and in adults are 3.2% and 0.502 micron 2, respectively. The events of alteration in junctional morphology during lamprey biliary atresia is in many ways comparable to the changes in gap junctions and zonulae occludentes during experimental and pathological intra- and extrahepatic cholestasis in mammals.     

The role of albumin in the hepatic transport of bilirubin: studies in mutant analbuminemic rats

Bilirubin and other cholephilic organic anions are bound to albumin in the circulation; their hepatic uptake involves a carrier-mediated process. To investigate the possible role of serum albumin in the transhepatic transport of a cholephilic ligand, plasma clearance of radioactive bilirubin and its biliary excretion as well as its interaction with plasma proteins were compared between normal and mutant analbuminemic rats (NAR). With a tracer amount of 3H-labeled bilirubin, its plasma clearance and biliary excretion were comparable in both animal groups. However, the plasma clearance of a loading dose of the ligand was significantly increased and its biliary recovery was low in NAR as compared with normal animals. In accord with these findings in vivo, gel permeation chromatographic analysis revealed that the bilirubin binding capacity of serum proteins was significantly lower in NAR than in control animals. When bilirubin was administered to NAR as a mixture with equimolar albumin, its plasma disappearance was considerably decreased and its biliary recovery was increased. Similar effects were observed when albumin was replaced by an equimolar amount of glutathione S-transferases (ligandins). These observations indicate that, although ligand-protein interaction in the circulation is important for directing bilirubin to the plasma membranes of the hepatocyte, this mechanism is not specific for albumin.     

胆道梗阻合并胆道感染的病原学特征和危险因素及与肝脏损伤的关系研究

目的:探讨胆道梗阻合并胆道感染的病原学特征和危险因素,并分析胆道感染与肝脏损伤的关系。方法:回顾性分析250例胆道梗阻患者的临床资料,分析胆道梗阻合并胆道感染的病原菌分布和主要病原菌的耐药性,分析胆道梗阻合并胆道感染的危险因素,比较各组的肝功能指标[天冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)、谷氨酰转移酶(GGT)、直接胆红素(DBIL)]和肝纤维化指标[层黏蛋白(LN)、透明质酸(HA)、Ⅲ型前胶原(PCⅢ)、Ⅳ型胶原(Ⅳ-C)]。结果:250例胆道梗阻中共有132例合并胆道感染,感染率为52.80%,共分离出病原菌150株,以革兰阴性菌和革兰阳性菌为主。粪肠球菌对红霉素的耐药率最高,屎肠球菌对林可霉素的耐药率最高,均对万古霉素的耐药率最低;大肠埃希菌和肺炎克雷伯菌均对氨苄西林的耐药率最高,对妥布霉素的耐药率最低。年龄≥60岁、有胆道手术史、肝功能Child-Pugh评分≥11分是胆道梗阻合并胆道感染的危险因素(P<0.05)。胆道感染组的AST、ALT、GGT、DBIL、LN、HA、PCⅢ、Ⅳ-C水平高于无胆道感染组和对照组,且无胆道感染组高于对照组(P<0.05)。结论:胆道梗阻患者胆道感染的发生率较高,并且胆道感染会进一步加重胆道梗阻患者的肝脏损伤,临床应根据其病原学特征和危险因素做好相应的防治工作。     

Screening of newborn infants for cholestatic hepatobiliary disease with tandem mass spectrometry

ObjectiveTo assess the feasibility of screening for cholestatic hepatobiliary disease and extrahepatic biliary atresia by using tandem mass spectrometry to measure conjugated bile acids in dried blood spots obtained from newborn infants at 7-10 days of age for the Guthrie test.SettingThree tertiary referral clinics and regional neonatal screening laboratories.DesignUnused blood spots from the Guthrie test were retrieved for infants presenting with cholestatic hepatobiliary disease and from the two cards stored on either side of each card from an index child. Concentrations of conjugated bile acids measured by tandem mass spectrometry in the two groups were compared.Results218 children with cholestatic hepatobiliary disease were eligible for inclusion in the study. Two children without a final diagnosis and five who presented at <14 days of age were excluded. Usable blood spots were obtained from 177 index children and 708 comparison children. Mean concentrations of all four bile acid species were significantly raised in children with cholestatic hepatobiliary disease and extrahepatic biliary atresia compared with the unaffected children (P<0.0001). Of 177 children with cholestatic hepatobiliary disease, 104 (59%) had a total bile acid concentration >33 μmol/l (97.5th centile value for comparison group). Of the 61 with extrahepatic biliary atresia, 47 (77%) had total bile acid concentrations >33 μmol/l. Taurotrihydroxycholanoate and total bile acid concentrations were the best predictors of both conditions. For all cholestatic hepatobiliary disease, a cut off level of total bile acid concentration of 30 μmol/l gave a sensitivity of 62% and a specificity of 96%, while the corresponding values for extrahepatic biliary atresia were 79% and 96%.ConclusionMost children who present with extrahepatic biliary atresia and other forms of cholestatic hepatobiliary disease have significantly raised concentrations of conjugated bile acids as measured by tandem mass spectrometry at the time when samples are taken for the Guthrie test. Unfortunately the separation between the concentrations in these infants and those in the general population is not sufficient to make mass screening for cholestatic hepatobiliary disease a feasible option with this method alone.

Key messages

• The prognosis of cholestatic hepatobiliary disease in infancy, in particular biliary atresia, is improved by early detection
• Infants destined to present with cholestatic jaundice in the first few months of life have raised concentrations of bile acids in the blood spots obtained at 7-10 days for current neonatal screening programmes
• Tandem mass spectrometry can be used to detect this marker of neonatal cholestasis
• Unfortunately there is too much overlap between bile acid concentrations in infants with cholestasis and those in control infants for this to be used as a single screening test for cholestatic hepatobiliary disease in general and biliary atresia
• Tandem mass spectrometry is a powerful tool for neonatal screening but every potential application must be carefully assessed