Performance of Non-invasive Blood Parameters for Ruling Out Significant Liver Fibrosis in Patients with Chronic Hepatitis B

Background and Aims: Evaluation of significant liver fibrosis is important for treatment decision and treatment response evaluation in patients with chronic hepatitis B. Since liver biopsy is invasive and transient elastography (TE) has limited availability, various non-invasive blood parameters need evaluation for their capabilities for detection of significant fibrosis. Methods: In this retrospective study, records of patients who had undergone liver biopsy for treatment-naïve chronic hepatitis B were evaluated to obtain various non-invasive blood parameters (aspartate aminotransferase-to-platelet ratio index [referred to as APRI], Fibrosis-4 score [referred to as FIB-4], gamma-glutamyl transpeptidase-to-platelet ratio [referred to as GPR], and gamma-glutamyl transpeptidase-to-albumin ratio [referred to as GAR]), in addition to TE, to assess significant liver fibrosis and compare these to fibrosis stage in liver biopsy. Results: A total of 113 patients were included in the study (median age 33 [interquartile range: 11-82 years], 74% males). Most (75%) patients were HBeAg-negative. The liver biopsy revealed significant fibrosis (Ishak ≥3) in 13% of the patients and nil or mild fibrosis (Ishak <3) in 87% of the patients. TE findings were available for 85 patients, APRI and FIB-4 for 95 patients, GPR for 79 patients, and GAR for 78 patients. The median values of all the parameters were significantly higher in patients with significant fibrosis, as compared to patients with non-significant fibrosis, and all the blood parameters as well as TE were able to identify patients with significant fibrosis significantly well (p<0.05). All non-invasive parameters had low positive predictive value but negative predictive value above 92%. Compared to TE, all the non-invasive blood parameters had similar area under the curve for detecting significant fibrosis, with excellent negative predictive value (≥93%). Conclusions: Non-invasive blood parameters (APRI, FIB-4, GPR, and GAR) with negative predictive values above 93% are excellent parameters for ruling-out significant fibrosis in patients with chronic hepatitis B. These can be used at bedside in place of TE.