TBA (22W156)

Angiopoietin 2 – A Potential Biomarker of Fibrosis in Chronic Liver Disease

Author(s)

C Walker 1, T Butler 2, C Deane 1, F O’Hara 1,2, B Ryan 1, A O’Connor 1, S O’Donnell 1, N Breslin 1, D Mc Namara 1,2

Department(s)/Institutions

Department of Gastroenterology, Tallaght University Hospital, Dublin, Ireland 1 Trinity Academic Gastroenterology Group, Trinity College Dublin, Dublin, Ireland 2

Introduction

Angiogenesis is associated with fibrosis in liver disease. Angiopoietin-2 (Ang2) is a key factor in the angiopoietin / tyrosine kinase signalling pathway, and higher levels may reflect fibrosis.

Aims/Background

Examine the relationship between Ang2 and fibrosis in people with known and suspected liver disease.

Method

A prospective single centre comparison of Ang2 levels with fibrosis scores. All patients referred for fibroscan were consecutively recruited. Following informed consent, subjects underwent standard liver elastography and blood tests for FIB-4 and Ang2 assessment. Exclusion criteria: medications and conditions known to alter Ang2 or over-estimate fibrosis. Serum Ang2 levels were determined in batches using a commercially available ELISA. Basic demographics, CAP, FIB4, fibrosis score, and disease specific fibrosis category (F0-F4) were compared with Ang-2 levels, using Pearson’s correlation coefficient and Tukey’s test as appropriate.

Results

In all, 61 patients were recruited. Indications included NAFLD(n=21), ALD(n=18), haemochromatosis(n=6), autoimmune hepatitis(n=5), PBC(n=4), drug induced liver injury(n=2), and hepatitis B(n=1). Of these 34, 14, 13 had F1, F1-3 and F4 scores respectively. There was a positive correlation with increased levels of Ang2 and higher fibrosis scores, Pearson’s r=0.628,p<0.0000001, 95%CI 0.4467-0.7596. Ang2 levels were not affected by age, CAP or FIB-4 scores. Ang2 levels increased according to disease specific fibrosis category. Mean Ang2 levels were statistically higher in the F4 group (6051pg/ml) compared to F1-3 (3169pg/ml,p<0.0003, 95%CI -4531 to -1232) and F0 (2858pg/ml,p< 0.0001, 95%CI -4589 to -1796) cohorts.

Conclusions

Increased Ang2 levels correlate with liver fibrosis irrespective of aetiology. Further investigation of Ang2 as a potential biomarker for fibrosis is warranted.