Chronic Hepatitis C Patients with Obesity: Do we Need two Operators for Accurate Evaluation of Liver Stiffness?

INTRODUCTION AND AIM: Transient elastography is gaining popularity as a non-invasive method for predicting liver fibrosis, but inter observer agreement and factors influencing reproducibility have not been adequately assessed.

MATERIAL AND METHODS: This cross-sectional study was conducted at Specialized Medical Hospital and the Egyptian Liver Foundation, Mansoura, Egypt. The inclusion criteria were: age older than 18 years and chronic infection by hepatitis C. The exclusion criteria were the presence of ascites, pacemaker or pregnancy. Three hundred and fifty-six patients participated in the study. Therefore, 356 pairs of exams were done by two operators on the same day.

RESULTS: The overall inter observer agreement ICC was 0.921. The correlation the two operators was excellent (Spearman's value q = 0.808, p < 0.001). Inter-observer reliability values were κ = 0.557 (p < 0.001). A not negligible discordance of fibrosis staging between operators was observed (87 cases, 24.4%). Discordance of at least one stage and for two or more stages of fibrosis occurred in 60 (16.9%) and 27 cases (7.6%) respectively. Obesity (BMI ≥ 30 kg/m2) is the main factor associated with discordance (p = 0.002).

CONCLUSION: Although liver stiffness measurement has had an excellent correlation between the two operators, TE presented an inter-observer variability that may not be negligible.