Histological study of the remnant of porta hepatis in patients with extrahepatic biliary atresia - A computed picture analysis of 30 cases

Portal plate bile duct diameter in biliary atresia is associated with long-term outcome

PURPOSE

Kasai portoenterostomy (KPE) is the only treatment currently available for biliary atresia (BA). Age at KPE and surgical experience are prognostic factors for a successful KPE. Here, we aimed to assess whether the size of bile ductules at the porta hepatis during KPE correlates with KPE success and transplant-free survival (TFS).

METHODS

A retrospective analysis of patients diagnosed with BA during 2000-2019. Porta hepatis biopsies were reviewed for diameters of five representative ducts, and a mean ductal diameter (MDD) was calculated. Laboratory values including pre- and postoperative bilirubin levels were analyzed.

RESULTS

The cohort included 77 patients; for 33, ductal plate biopsy was available. KPE was successful in six of eight patients with MDD ≥ 50 µm, and in five of 25 with MDD < 50 µm, p = 0.008, OR = 12.0 (95% CI 1.83-78.3). Ten-year survival with native liver was higher in patients with MDD ≥ 50 µm than in patients with MDD < 50 µm, p < 0.001, HR 0.038 (95% CI 0.007-0.207). Direct bilirubin < 1 mg/dl 3 months post-KPE was associated with improved 2-year post-KPE TFS (27.7% vs. 13.9%, p < 0.0001).

CONCLUSIONS

MDD ≥ 50 µm correlates with KPE success and a higher rate of TFS. Direct bilirubin < 1 mg/dl 3 months post-operation may serve as a marker of successful biliary excretion, and a predictor of 2-year TFS.

Hepatic expression of multidrug resistance protein 2 in biliary atresia

Background

Biliary atresia (BA) is an idiopathic inflammatory obliterative cholangiopathy of neonates, leading to progressive biliary cirrhosis. Hepatoportoenterostomy (Kasai procedure) can cure jaundice in 30% to 80% of patients. Postoperative clearance of jaundice is one of the most important factors influencing long-term outcomes of BA patients. Multidrug resistance protein 2 (MRP2) is one of the canalicular export pumps located in hepatocytes; it exports organic anions and their conjugates (e.g., bilirubin) into bile canaliculus. Although MRP2 is an essential transporter for the excretion of bilirubin, its role in the clinical course of BA patients is unclear. The present study investigated the relationship between hepatic MRP2 expression and clinical course in BA patients, with particular emphasis in curing jaundice after hepatoportoenterostomy.

Results

No significant differences in hepatic MRP2 expression level were observed between BA and controls groups. There was no correlation between MRP2 expression and age at time of surgery in BA and control groups. In BA patients, MRP2 expression level in the jaundice and jaundice-free group did not differ significantly (2.0 × 10^-4 vs 3.1 × 10^-4, p = 0.094). Although the serum level of total bilirubin just before surgery did not correlate with MRP2 expression level (rs = 0.031, p = 0.914), the serum level of total bilirubin measured at 2 weeks (rs = -0.569, p = 0.034) and 4 weeks after surgery (rs = -0.620, p = 0.018) were significantly correlated with MRP2 expression level. Furthermore, MRP2 expression level was inversely correlated with ratio of change in serum total bilirubin level over 4 weeks (rs = -0.676, p = 0.008), which represents the serum bilirubin level measured at 4 weeks after surgery divided by value just before surgery. There was no correlation between expression level of MRP2 and nuclear receptors, such as retinoid × receptor α, farnesoid × receptor, pregnane × receptor, or constitutive androstane receptor.

Conclusions

Hepatic MRP2 expression level was associated with postoperative clearance of jaundice in BA patients, at least within 1 month after hepatoportoenterostomy. This finding suggests that not only morphological appearance of the liver tissue but also the biological status of hepatocytes is important for BA pathophysiology.

Liver and portal histopathological correlation with age and survival in extra hepatic biliary atresia

AIM

To grade histopathological parameters in biliary atresia (BA) and correlate it with advancing age and outcome.

METHOD

Liver and porta hepatis biopsies of 18 BA cases were graded for cholestasis (C), hepatocellular degeneration (HD), bile duct proliferation (BDP), bile duct fibrosis (BDF), bile duct inflammation (BDI), portal edema (PE), portal inflammation (PI) and portal fibrosis (PF) with a total histopathological score (THS) of 25. Confidence intervals were calculated. Image analysis at porta hepatis for largest subhepatic bile ductule diameter (BDD) and area was correlated with liver histopathology. Patients were followed up to at least 1 year after surgery. Four cases of neonatal autopsies were taken as control.

RESULTS

Mean age at Kasai was 95.5 + 32.03 (51-172) days. Mean THS was 16.83 + 2.57 (13-23) with no significant difference in relation to age <90; >90 days (p = 0.4410) or age <60; 61-90; 91-120; >121 days (p = 0.6549). There was no significant difference with relation to age in grading of parameters; C (p = 1.000) HD (p = 0.638), BDP (p = 0.530), BDF (p = 0.342), BDI (p = 0.395), PE (p = 0.476), PI (p = 0.342), PF (p = 0.530), BDD (p = 0.1097) and area (p = 0.1097). There was no significant difference between survival and age at operation (p = 0.4178) or THS (p = 0.3025).

CONCLUSION

Advanced histopathological findings even at younger age suggests the need to consider BA as an emergency.

[New developments in pediatric surgery]

New concepts in pediatric surgery have been developed concerning inter-disciplinary problems such as ureter implantation or urinary undiversion as well as deformities of abdominal organs such as biliary atresia, anorectal malformations, adrenogenital syndrome and sinus urogenitalis. Considerable improvements in fetal surgery as a part of pediatric surgery were achieved. For diagnostic, surgical and ethical reasons, however, these efforts are, for the time being, only of theoretical interest.