The Concept of Hepatic Artery-Bile Duct Parallelism in the Diagnosis of Ductopenia in Liver Biopsy Samples
RK Moreira, W Chopp, MK Washington. Columbia University, New York, NY; Vanderbilt University, Nashville, TN
Background: “Absence of bile ducts (BD) in >50% of portal tracts” is currently the most widely accepted criterion for the diagnosis of ductopenia. The potential use of hepatic artery (HA) branches as landmark structures for a more precise quantitative assessment of interlobular BDs in ductopenic disorders is explored in this study.
Design: In the first part of the study, 500 portal tracts from histologically normal liver resection specimens were studied and a database of morphometric parameters was created. An “unpaired HA” was defined as a) a HA branch of any size within a complete portal tract not accompanied by a BD; b) a HA branch measuring >20 μm in an incomplete portal tract with no BD present within a radius of 10 HA diameters. In the second part, biopsies from patients with hepatitis C, autoimmune hepatitis, steatohepatitis, and post-perfusion liver allograft biopsies (group 1, n=30) were analyzed and the following diagnostic criteria for ductopenia were defined: 1-presence of at least one unpaired HA in >10% of all portal tracts; 2-At least 2 unpaired HAs present in different portal tracts in a given sample, regardless of the total number of portal tracts. These criteria were then applied to biopsies from patients with PBC and suspected chronic allograft rejection (group 2, n=32).
Results: HA-BD parallelism was seen in 96.6% of normal portal tracts. The mean HA-BD distance was 4 + 2.8 HA diameters. BD loss was detected in 59.4% of patients in group 2 by the unpaired HA method compared to 43.7% (P=0.31), 21.9% (P=0.005), and 12.5% (P=0.001) by the traditional method, depending on specific adequacy criteria utilized (no adequacy criteria, >10 portal tracts, or >5 complete portal tracts per biopsy, respectively). The percentage of portal tracts containing BDs was significantly affected by the degree of portal inflammation, fibrosis stage, percentage of complete portal tracts, and biopsy width, while none of these factors influenced the prevalence of unpaired arteries.
Conclusions: The concept of HA-BD parallelism can be used to reliably identify bile duct loss and establish the presence of ductopenia in biopsy samples. The unpaired hepatic artery method described in this study is not influenced by factors that can affect the percentage of portal tracts containing BDs and may be useful in the evaluation of ductopenia, as mild degrees of bile duct loss may be more accurately detected by this method compared to traditional criteria.
Category: Liver & Pancreas
Monday, March 22, 2010 1:00 PM
Poster Session II # 181, Monday Afternoon