CEUS detection of biliary ischaemia during the first 4 weeks after liver transplantation predicts non-anastomotic biliary stricture

Article type: Research Article

Authors: Zheng, Bo-wen^{a; 1} | Yi, Shu-hong^{b; 1} | Wu, Tao^a | Liao, Mei^a | Zhang, Ying-cai^b | Yuan, Lian-xiong^c | Zheng, Rong-qin^a | Yang, Yang^b | Ren, Jie^{a; *}

Affiliations: [a] Department of Medical Ultrasonics, The Third Affiliated Hospital of Sun Yat-sen University, Guangdong Province Key Laboratory of Hepatology Research, Guangzhou, Guangdong, People’s Republic of China | [b] Department of Liver Transplantation, The Third Affiliated Hospital of Sun Yat-Sen University, Guangdong Province Key Laboratory of Hepatology Research, Guangzhou, Guangdong, People’s Republic of China | [c] Department of Scientific Research, The Third Affiliated Hospital of Sun Yat-Sen University, Guangdong Province Key Laboratory of Hepatology Research, Guangzhou, Guangdong, People’s Republic of China

Correspondence: [*] Corresponding author: Jie Ren, Department of Medical Ultrasonics, The Third Affiliated Hospital of Sun Yat-sen University, Guangdong Province Key Laboratory of Hepatology Research, 600 Tianhe Road, Guangzhou, Guangdong, People’s Republic of China. Tel.: +86 020 85253333; Fax: +86 020 85253336; E-mail: [email protected].

Note: [1] These authors contributed equally to this work.

Abstract: BACKGROUND:Biliary ischaemia is an important factor in the pathogenesis of non-anastomotic biliary stricture (NAS) after liver transplantation (LT). Contrast-enhanced ultrasound (CEUS) can be used to detect biliary ischaemia, but no study has examined the utility of CEUS in predicting NAS. OBJECTIVE:To evaluate whether repeated CEUS as a non-invasive method of biliary ischaemia can identify NAS. METHODS:Consecutive LT patients who underwent CEUS examinations at 1–4 weeks after LT from September 2012 to December 2015 at our institution were included. The CEUS images and clinical data were analysed. RESULTS:Among 116 eligible LT patients, 39 (33.6%) were diagnosed with NAS within 1 year after LT. The patients with NAS had a significantly higher CEUS score at weeks 2–4 (all P < 0.05) and a higher slope of CEUS score progression (0.480 vs –0.044, P < 0.001). The accuracy of CEUS in identifying NAS improved over time after LT, reaching its maximum at week 4, with a sensitivity of 66.7%, a specificity of 87.9%, a positive predictive value (PPV) of 75.9%, a negative predictive value (NPV) of 82.3%, and an accuracy of 80.2%in the full cohort when a CEUS score≥3 was used as the cut-off. Multivariate analysis identified gamma-glutamyl transpeptidase (GGT), alanine transaminase (ALT) and the CEUS score at week 4 as independent predictors of NAS. In the task of identifying NAS, an NAS score combining the above 3 variables at week 4 showed areas under the receiver operating characteristic curve of 0.88 (95%CI, 0.78–0.99) in the estimation group (n = 60) and 0.82 (95%CI, 0.69–0.96) in the validation group (n = 56). An NAS score cut-off of 0.396 identified 87.2%of NAS cases in the estimation group, with a PPV of 93.3%; and 75.0%of NAS cases in the validation group, with a PPV of 58.8%. CONCLUSIONS:CEUS examination during the first 4 weeks is useful in assessing the risk of NAS within 1 year after LT. In particular, an NAS score combining the CEUS score, GGT level, and ALT level at week 4 can be used to accurately predict the risk of NAS in LT patients.

Keywords: Ultrasonography, contrast agent BR1, liver transplantation, microcirculation, ischemia, biliary tract diseases

DOI: 10.3233/CH-211097

Journal: Clinical Hemorheology and Microcirculation, vol. 79, no. 4, pp. 519-530, 2021