Epidemiology of biliary atresia in France: a national study 1986-96

Nonobstructive neonatal cholestasis: clinical outcome and scoring of the histopathological changes in liver biopsies

The clinical outcome of nonobstructive neonatal cholestasis (NC) cases varies greatly and the prognosis is generally unpredictable. In this study, we aimed to evaluate the prognostic benefits of qualitative analysis of histopathological changes in nonobstructive NC cases. A total of 28 nonobstructive NC cases (18 neonatal hepatitis; 10 intrahepatic bile duct paucity) were studied. We analyzed the relationship between histopathological and clinical parameters. Hepatic inflammation, bridging necrosis, pericellular fibrosis, giant cell transformation, and extramedullary hematopoiesis were evaluated and scored according to their absence or presence in each case. The sum of the histopathological scores was accepted as "total pathological injury score." The height percentiles, the presence and the degree of hepatomegaly and ascites, and serum alanine aminotransferase (ALT), albumin, and bilirubin levels and prothrombin time were also evaluated and scored. The patients were divided into 2 clinical course groups considered "good" or "bad" according to the total clinical scores. For statistical analysis, Pearson's chi-square test, Mann-Whitney U-test, and receiver operating characteristic curve were used. We found a statistically significant negative relation between the clinical course and total pathological injury score (P = 0.042) and pericellular fibrosis (P = 0.016). In conclusion, during the interpretation of liver biopsies of nonobstructive NC, scoring of histopathological changes should be done for assessing the clinical prognostic outcome.

Unraveling the pathogenesis and etiology of biliary atresia

Biliary atresia (BA) is the most common and important neonatal hepatobiliary disorder. Because current treatment is inadequate, there is an urgent need to better understand the etiology and pathogenesis of BA. Two major forms of BA are recognized: an embryonic form associated with other congenital anomalies and a perinatal form in which bile ducts were presumably formed normally but underwent fibro-obliteration in the perinatal period. There are currently several proposed pathogenic pathways leading to the phenotype of BA, including an immune or autoimmune response to a perinatal insult (e.g. cholangiotropic viral infection) and dysregulated embryonic development of the extra- or intrahepatic biliary system. Recent advances in developmental biology, genomics and genetics, and cell immunology and biology, coupled with the development of appropriate animal models, have provided support for these postulated mechanisms. Future investigations combining animal model work and evaluation of clinical specimens holds the promise of identifying the etiology of BA and providing a scientific basis for treatment and preventative interventions.

Neonatal surgical jaundice revisited

Neonatal hyperbilirubinemia is a common problem in newborn nurseries and manifest clinically as jaundice. Nearly 25-50% of all newborns and a much higher percentage of premature babies develop hyperbilirubinemia. This is mostly physiological, but a small percentage of these babies have pathological jaundice, requiring detailed investigations and management. It is also absolutely essential to consider a possibility of extra-hepatic biliary atresia early, during management of a case of neonatal direct hyperbilirubinemia as early surgical intervention results in a better outcome in EHBA. This article aims to describe the diagnostic approach to neonatal hyperbilirubinemia with special emphasis on conditions requiring surgical intervention also it throws light on present status of EHBA in Indian circumstances.

Human leukocyte antigens in Japanese patients with biliary atresia: Retrospective analysis of patients who underwent living donor liver transplantation

Biliary atresia (BA) is a neonatal obstructive cholangiopathy characterized by a fibrosclerosing obliteration of the extrahepatic bile duct. The aim of this study was to investigate the relationship between human leukocyte antigens (HLA) and susceptibility to BA. We retrospectively analyzed 392 Japanese patients with BA and without extrahepatic anomalies who underwent living donor liver transplantations at our institute. Healthy Japanese volunteers (n = 828) served as normal controls. A significant positive association was observed between BA and HLA-DR2 (39.0% of patients vs. 30.4% of controls, odds ratio = 1.46, p = 0.029). Two-locus analyses disclosed that DR2 was not independently associated with BA, but the increased frequency of HLA-A24 and -B52 reflected the linkage disequilibrium between -A24, -B52, and -DR2. Moreover, the frequency of the haplotype HLA-A24-B52-DR2 was significantly higher in patients with BA than in the general Japanese populations described in the literature (odds ratio = 2.20, p = 0.00124). These results indicate that the gene for BA susceptibility is in close linkage disequilibrium with the HLA-A24-B52-DR2 haplotype observed in the Japanese population. We speculate that a gene at the locus close to HLA plays an important role in the pathogenesis of BA.

Outcome in adulthood of biliary atresia: a study of 63 patients who survived for over 20 years with their native liver

To define the long-term prognosis of children undergoing the Kasai operation for biliary atresia, a retrospective study was undertaken comprising 271 patients operated between 1968 and 1983. Twenty years after surgery, 63 (23%) were alive with their native liver. Serum bilirubin was normal in 21 of these patients, 12 also had normal serum aminotransferase and gamma-glutamyltransferase activities, all but 2 had signs of cirrhosis, 44 had signs of portal hypertension, 19 had late bacterial cholangitis, and 6 had gallstones. Seven female patients gave birth to 9 children, and 3 male patients fathered 6 children. After age 20, 2 patients died of liver failure and 14 underwent or are awaiting liver transplantation. Twenty-year survival with native liver was significantly better in children with biliary atresia restricted to the hepatic ducts or with cysts at the porta hepatis. In conclusion, in the long term, less than 18% of infants with biliary atresia who are treated with corrective surgery may avoid liver transplantation, but even these patients require assiduous lifelong care.

Detection of Helicobacter ganmani-like 16S rDNA in pediatric liver tissue

BACKGROUND

To determine the presence of Helicobacter species in the liver biopsy specimens from children with various chronic liver diseases as data in adult literature suggests a possible role of these bacteria in their pathogenesis.

MATERIALS AND METHODS

Paraffin sections of 61 liver biopsies of pediatric patients with miscellaneous diseases and autopsy liver tissue from 10 control subjects with no evidence of preexisting liver disease were examined for the presence of Helicobacter species by a genus-specific seminested polymerase chain reaction (PCR) assay. PCR-products of positive samples were further characterized by denaturing gradient gel electrophoresis (DGGE) and DNA-sequence analysis. Based on those results, a seminested PCR assay for H. ganmani was developed and applied to the samples.

RESULTS

On analysis, 40/61 patient samples were positive in the genus-specific Helicobacter PCR and 4/10 from the control group. The nucleotide sequences of 16S rDNA fragments were 99-100% similar to mainly Helicobacter sp. 'liver' and H. ganmani. PCR-products similar to H. canis and H. bilis were also found. The 16S rDNAs of control specimens showed similarity to Helicobacter sp. 'liver'. In the H. ganmani-specific PCR analysis 19 patients, but none of the controls, were positive.

CONCLUSIONS

Amplified Helicobacter 16S rDNAs were related to Helicobacter sp. 'liver' or H. ganmani in liver biopsy specimens of pediatric patients. The possible significance of Helicobacter species in pediatric liver diseases needs to be evaluated further in prospective studies.

The epidemiology of extrahepatic biliary atresia in New York State, 1983-98

The aetiology of biliary atresia, the leading cause of neonatal extrahepatic jaundice and the main indication for liver transplantation in children, is unknown. Recent research has focused on an infectious aetiology and the development of viral models in animals. The few published epidemiological studies report conflicting results for seasonal, geographical, and racial variations in incidence. In this study, New York State (NYS) Congenital Malformations Registry data from 1983 to 1998 were compared with resident live birth certificate data. County of residence, birth date, gestational age, birthweight, gender, maternal race and maternal age were extracted from the birth certificate data. Isolated and sequence cases were combined for analysis. Observed and expected numbers of cases were calculated by NYS region. Overall, 369 biliary atresia cases were reported in the 16-year study period, a rate of 0.85 [95% CI 0.76, 0.93] per 10,000 live births. Of these, 249 isolated/sequence cases were ascertained, a rate of 0.57 [95% CI 0.50, 0.64] per 10,000 live births. The rate ratio of biliary atresia in New York City (NYC) compared with other NYS was 2.19 [95% CI 1.69, 2.84]. Seasonal patterns varied by region with spring births at highest risk in NYC and September to November births at highest risk in other NYS. The rate ratio in black vs. white mothers was 1.94 [95% CI 1.48, 2.54]. Birthweight and gestational age were associated with biliary atresia with preterm low-birthweight infants at highest risk [RR 3.24, 95% CI 2.20, 4.76]. The association of isolated/sequence biliary atresia with season, preterm birth, and low birthweight in our study supports an infectious disease hypothesis.

Biliary atresia revisited

Extrahepatic biliary atresia (EHBA) is an inflammatory fibrosing process affecting the extrahepatic and intrahepatic biliary tree resulting in fibrous obliteration of the extrahepatic biliary tract, ductopenia of intrahepatic bile ducts, and biliary cirrhosis. EHBA is divided into a correctable and a noncorrectable type with focal patency of the otherwise atretic biliary tree in the former and no patency of the biliary tree in the noncorrectable type. EHBA is divided in a fetal, prenatal or embryonic, and a more common, perinatal, acquired form. The symptoms of the former start shortly after birth and there is frequently an association with a variety of congenital anomalies. Children with the perinatal form become jaundiced several weeks after birth; no associated congenital anomalies are present. Morphologically, an inflammatory and fibrosing process of the extrahepatic biliary tree leads to complete lumenal obliteration. The liver is characterized by a nonspecific giant cell transformation, and portal expansion by fibrous connective tissue with marked ductular proliferation. With time, ductopenia and biliary cirrhosis develop. The diffential diagnosis with other conditions with similar microscopic patterns such as as alpha-1 antitrypsin deficiency, total parental nutrition, obstruction by a choledochal cyst, arteriohepatic dysplasia, familial progressive intrahepatic cholestasis, and alteration of the bile acid metabolism is discussed. In the fetal group, abnormalities in different genes seem to play a role; ductal plate malformation is another possibility. Different etiologies have been postulated in the perinatal form of EHBA: genetic susceptibility, vascular factors, toxins, and infections mainly by rotavirus and reovirus. The pathogenesis is complex. EHBA is a heterogenous disease, resulting from a combination of genetic factors, insults, and activation of different genetic and immunologic pathways. The treatment of EHBA is surgical, with anastomosis between the biliary tree and the intestine in the correctable type and a hepatic portoenterostomy (HPE) for the noncorrectable group. HPE is a temporizing treatment allowing the infant to develop and grow, followed in the majority of the patients by liver transplantation.

Biliary atresia

BA is a rare disease of unclear etiology; nevertheless, its impact in the field of pediatric hepatology is significant. It is the most common surgically correctable cause of neonatal cholestasis and is the most common pediatric disease referred for liver transplantation. Little progress has been made with regard to improving outcome or understanding its pathogenesis in the past decade. Fortunately, however, a national, government-sponsored collaborative endeavor has begun that will hopefully make a significant impact upon the progress of designing new treatments for BA and develop a better understanding of its pathogenesis.

Altered expression of genes involved in hepatic morphogenesis and fibrogenesis are identified by cDNA microarray analysis in biliary atresia

Biliary atresia (BA) is characterized by a progressive, sclerosing, inflammatory process that leads to cirrhosis in infancy. Although it is the most common indication for liver transplantation in early childhood, little is known about its etiopathogenesis. To elucidate factors involved in this process, we performed comprehensive genome-wide gene expression analysis using complementary DNA (cDNA) microarrays. We compared messenger RNA expression levels of approximately 18,000 human genes from normal, diseased control, and end-stage BA livers. Reverse-transcription polymerase chain reaction (RT-PCR) and Northern blot analysis were performed to confirm changes in gene expression. Cluster and principal component analysis showed that all BA samples clustered together, forming a distinct group well separated from normal and diseased controls. We further identified 35 genes and ESTs whose expression differentiated BA from normal and diseased controls. Most of these genes are known to be associated with cell signaling, transcription regulation, hepatic development, morphogenesis, and fibrogenesis. In conclusion, this study serves to delineate processes that are involved in the pathogenesis of BA.

Five- and 10-year survival rates after surgery for biliary atresia: a report from the Japanese Biliary Atresia Registry

PURPOSE

The aim of this study was to elucidate the epidemiology and short- and long-term results of biliary atresia in Japan analyzing the data of the Japanese Biliary Atresia Registry (JBAR).

METHODS

In 1989, the Japanese Biliary Atresia Society started a nationwide registry, JBAR, to investigate all aspects of biliary atresia. A total of 1,381 patients, 863 girls, 507 boys, and 11 unknown, were registered between 1989 and 1999. JBAR includes an initial and follow-up questionnaires. Using these patients' data, the incidence, sex distribution, associated anomalies, the type of obstruction, the type of operation, and the surgical results were evaluated. The 5- and the 10-year results of 735 patients who were registered initially in or before 1994 also were analyzed.

RESULTS

The incidence of biliary atresia was 1 in 9,640 live births. One hundred sixty-four patients (11.9%) had type I atresia of the common bile duct, 34 (2.5%) had type II atresia of the hepatic ducts, and 1,162 (84.1%) had type III atresia at the porta hepatis. Congenital associated anomalies were found in 19.6% of the patients including 33 cases associated with polysplenia. Impact of the age at operation on bile flow was not clear until 90 days of age, and after 90 days the bile flow rate worsened. The original Roux-en-Y procedure had been used in more than 50% of the patients since 1995. In 1999, 96% of the patients underwent the original Roux-en-Y procedure or the Roux-en-Y with an intestinal valve, and only 3 patients (3.5%) underwent other modifications. There were no significant differences in either the rate of disappearance of jaundice or the incidence of cholangitis among these 3 procedures. Of the 735 patients registered in or before 1994, 19 patients (2.6%) were lost to follow-up. The 5-year survival rates of patients registered in 1989, 1990, 1991, 1992, 1993, and 1994 were 62%, 64.5%, 61.3%, 59.0%, 58.7%, and 52.7% without liver transplantation (LTx), and 69.4%, 74.2%, 75.2%, 79.5%, 78%, and 78.3% with LTx, respectively. Although the overall 5-year survival rate changed from 69.4% to 78.3%, the difference was not statistically significant. According to the 10-year follow-up results of the 108 patients initially registered in 1989, 72 (66.7%) and 57 (52.8%) survived with and without the aid of LTx, respectively.

CONCLUSIONS

The overall 5- and 10-year survival rates were 75.3% (553 of 734) and 66.7% (72 of 108), respectively. In spite of the increasing number of survivors after LTx, there was no significant improvement in the 5-year survival rate. It was shown that the JBAR system was functioning well with only 19 patients lost to follow-up among the 743 patients registered from 1989 to 1994.

A population-based study on the incidence and possible pre- and perinatal etiologic risk factors of biliary atresia

OBJECTIVE

To study the incidence, etiologic risk factors, and outcome of biliary atresia.

STUDY DESIGN

Register study using Swedish national health databases. The study population consisted of 1,204,791 children, corresponding to 99% of the entire cohort of Swedish children born between 1987 and 1997, with an end point of follow-up at 2 years of age. Cases with biliary atresia with and without major heart malformations were identified with indicators from various national health databases.

RESULTS

Eighty-five cases with biliary atresia were identified, the incidence being 1 in 14,000. A major heart malformation was found in 13 (15%) cases. In a multivariate analysis, 4 independent risk factors were identified: high maternal age (odds ratio [OR] = 3.0), parity of at least 4 (OR = 2.2), prematurity (OR = 2.9), and low birth weight for gestational age (OR = 4.7). No significant differences were found in the distribution of birth months. The outcome did not differ between the two groups with and without major heart malformations, nor with respect to any of the risk factors.

CONCLUSIONS

The Swedish incidence of biliary atresia is similar to that found in other European countries. The identified risk factors may suggest the existence of a maternal vulnerability and the importance of viral infections transmitted from mother to fetus/neonate.

Biliary atresia: an update on our understanding of the disorder

Biliary atresia is the leading cause of cholestasis in infants younger than 3 months. It is also the leading indication for liver transplantation in children. This review focuses on recent advances in the etiology, diagnosis, and management of biliary atresia.

[Analysis of delay in diagnosis of extrahepatic biliary atresia]

Prognosis of extrahepatic biliary atresia depends on an early surgical treatment. This survey studied the delay to surgery of infants treated for biliary atresia and analysed the causes of late diagnosis and referral.

MATERIAL AND METHODS

Medical files of 21 infants treated for biliary atresia between 1988 and 1998 were retrospectively analysed.

RESULTS

Median age at biliary operation was 57 days and did not change during time. In only 3/21 cases, surgery was performed before 45 days of age. The first clinical or biological sign of cholestasis was noted at a median age of 12 days. In eight cases, the first medical visit for cholestasis (median age of 21 days) was not followed by a blood test. In 11 cases, infants presenting with biological cholestasis were referred to hospital more than seven days later. False diagnosis was noted in seven cases and delayed significantly the operation.

CONCLUSION

The delay to surgical treatment is too long and does not decrease whereas a majority of infants visit their physician early. Medical information is mandatory for all physicians taking care of infants.

Cholestatic syndromes

Continued advances in the field of liver cell biology and molecular biology have provided further insights into the normal physiology of bile secretion and the pathogenesis and therapy for cholestatic syndromes. Important new data have also been published about pathogenesis, clinical features, and treatment of primary biliary cirrhosis, primary sclerosing cholangitis, drug-induced cholestasis, and cholestatic syndromes caused by viral infections.