Biliary atresia: unity in diversity

The Impact of Male Gender and Thrombophilia on Disease Progression in Children with Biliary Atresia—A Single-Centre Cohort Study

Epidemiological evidence suggests that thrombophilic factors, including male sex, non-O blood type, MTHFRnt677TT mutation, factor V Leiden G1691A mutation, and prothrombin G20210A polymorphism, may contribute to the progression of fibrosis and occurrence of portal vein thrombosis in liver disease. We retrospectively investigated the effect of potentially thrombophilic factors on native liver survival as a patient-relevant endpoint of disease progression in a cohort of 142 children being followed up for biliary atresia at Hannover Medical School from April 2017 to October 2019. No significant association could be determined. There was no evidence for relevant differences in native liver survival for the Factor V Leiden G1691A mutation (hazard ratio [HR] = 0.86, 95% confidence interval [CI] 0.38–1.98, p = 0.73), prothrombin G20210A polymorphism (HR = 0.96, 95%CI 0.24–3.65, p = 0.96), non-O blood type (HR = 0.79, 95%CI 0.51–1.21, p = 0.28) or MTHFRnt677TT mutation (HR = 1.24, 95%CI 0.60–2.56, p = 0.56). A certain, albeit not strong, evidence of reduced native liver survival in male patients after Kasai hepatoportoenterostomy, particularly during the first 2000 days (42%; HR = 1.41, 95%CI 0.92–2.18, p = 0.11) was found. All children with pre-transplant portal vein thrombosis (n = 7) had non-O blood types. Larger multi-centre studies are necessary to show if the male sex or other thrombophilic factors could be potentially associated with reduced native liver survival.

Centralization of Biliary Atresia: Has Germany Learned Its Lessons?

INTRODUCTION

 The majority of pediatric surgeons and hepatologists recommend the centralization of biliary atresia (BA) treatment within experienced liver units. We aimed to investigate whether voluntary self-restriction and acceptance of the need for this change in practice changed the BA referral policy in Germany during the last decade.

MATERIALS AND METHODS

 In cooperation with pediatric surgeons, gastroenterologists or hepatologists, and pediatric liver transplant units, the 2-year follow-up data of infants with BA born in Germany between 2010 and 2014 were collected using www.bard-online.com or pseudonymized data transfer. Results were compared with our previous analysis of the outcome data of infants with BA born between 2001 and 2005 in Germany.

RESULT

 Overall, 173 infants with BA were identified, of whom 160 underwent Kasai portoenterostomy (KPE; 92.5%) and 13 (7.5%) underwent primary liver transplantation at 21 German centers. At 2-year follow-up, overall survival was 87.7% (vs. 81.9% in 2001-2005 [p = 0.19]), survival with native liver post-KPE was 29.2% (vs. 22.8% in 2001-2005 [p = 0.24]), and jaundice-free survival with native liver post-KPE was 24.0% (vs. 20.1% in 2001-2005 [p = 0.5]). Compared with the 2001-2005 analysis, all criteria showed improvement but the differences are statistically not significant.

CONCLUSION

 Our observation shows that KPE management requires improvement in Germany. Centralization of BA patients to German reference liver units is not yet mandatory. However, European and national efforts with regard to the centralization of rare diseases support our common endeavor in this direction.

Adjuvant Therapy with Budesonide Post-Kasai Reduces the Need for Liver Transplantation in Biliary Atresia

Based on the hypothesis that autoimmunological factors coregulate the pathomechanism in biliary atresia (BA), adjuvant therapy with steroids has become routine, although its efficacy has never been proven. In 2010, a study on the advantages of budesonide compared to prednisolone in autoimmune hepatitis gave rise to experimental therapy using budesonide as an adjuvant BA treatment. Ninety-five BA patients prospectively received a budesonide 2 mg/dose rectal foam daily for three months (SG). A case-matched control group (CG: 81) was retrospectively recruited. The outcome measures were survival with native liver (SNL), determined at six months and two years after the Kasai procedure. The follow-up rate was 100%. At six months, SNL was statistically not different but became so after two years (SG: 54%; CG: 32%; p < 0.001). No steroid-related side effects were observed, except for eight patients with finally caught-up growth retardation. This study demonstrates for the first time a significantly longer survival with native liver in patients with BA after adjuvant therapy. However, indication, dosage, and duration of any budesonide application is not given in neonates with BA. Hence, we suggest extending the postoperative use of budesonide in a multicenter observational study with a clearly defined follow-up protocol, particularly in terms of potentially underestimated side effects.

Severity of Ascites Is Associated with Increased Mortality in Patients with Cirrhosis Secondary to Biliary Atresia

BACKGROUND

Very few prior studies have investigated the presence of ascites as a prognostic factor in children with cirrhosis. To the best of our knowledge, there are no prior studies evaluating the relationship between severity of ascites and patient survival in children with biliary atresia and cirrhosis.

AIMS

To evaluate the association between severity of ascites and survival of children with cirrhosis and biliary atresia.

METHODS

All children with cirrhosis secondary to biliary atresia evaluated at our institution from 2000 to 2014 were included in this study. Patients were classified into four groups: NA = no ascites; A1 = grade 1 ascites; A2 = grade 2 ascites; and A3 = grade 3 ascites. The primary endpoint of the study was mortality within the first year after patient inclusion. Ninety-day mortality was also evaluated. Prognostic factors related to both endpoints also were studied.

RESULTS

One-year patient survival for NA was 97.1%, versus 80.8% for A1, versus 52% for A2, versus 13.6 for A3 (p < 0.001). The presence of ascites increased mortality by 17 times. In the multivariate analysis, clinically detectable ascites (HR 3.14, 95% CI 1.14-8.60, p = 0.026), lower sodium (HR 1.15, 95% CI 1.04-1.27, p = 0.006), higher bilirubin (HR 1.06, 95% CI 1.00-1.12, p = 0.023), and higher PELD score (HR 1.05, 95% CI 1.02-1.08, p = 0.001) were all associated with decreased survival. Lower serum sodium (HR 1.20, 95% CI 1.09-1.32, p < 0.001) and higher PELD score (HR 1.03, 95% CI 1.001-1.063, p = 0.043) were associated with increased 90-day mortality.

CONCLUSIONS

Clinically detectable ascites is associated with decreased 1-year survival of children with biliary atresia. These patients should be treated with caution and prioritized for liver transplantation.

Biliary atresia: pathology, etiology and pathogenesis

Biliary atresia is a progressive fibrosing obstructive cholangiopathy of the intrahepatic and extrahepatic biliary system, resulting in obstruction of bile flow and neonatal jaundice. Histopathological findings in liver biopsies include the expansion of the portal tracts, with edematous fibroplasia and bile ductular proliferation, with bile plugs in duct lumen. Lobular morphological features may include variable multinucleate giant cells, bilirubinostasis and hemopoiesis. The etiopathogenesis of biliary atresia is multifactorial and multiple pathomechanisms have been proposed. Experimental and clinical studies have suggested that viral infection initiates biliary epithelium destruction and release of antigens that trigger a Th1 immune response, which leads to further injury of the bile duct, resulting in inflammation and obstructive scarring of the biliary tree. It has also been postulated that biliary atresia is caused by a defect in the normal remodelling process. Genetic predisposition has also been proposed as a factor for the development of biliary atresia.