Noninvasive Evaluation of Liver Fibrosis in a Sample of Putative Inactive HBV Carriers in Rome, Italy

Background: Noninvasive methods are useful for investigating patients with chronic HBV infection. The severity of liver disease in inactive HBsAg carriers can be noninvasively assessed by transient elastography (TE) alone or in association with biochemical markers of fibrosis. Objectives: The study evaluates the effectiveness of the TE compared to common fibrosis scores (FSs), APRI, Forns Index, and FIB4, for identifying significant fibrosis in Italian and foreigner HBsAg carriers. To investigate the risk of progression of the liver disease, liver stiffness (LS) and HBV-DNA were monitored over time. Methods: Viral load, biochemical parameters, and LS have been retrospectively evaluated in 125 putative inactive HBV carriers, who visited two outpatient departments (Colleferro Hospital and INMP) from 01/03/2014 to 31/12/2019. Differences in clinical, biochemical, and demographic variables between Italians and foreigners were analyzed. 66 of 125 patients were followed up for 24 months by monitoring liver stiffness and HBV-DNA. Results: Mean overall LS was 5.55 ± 1.92 kPa; 18 (14.4%) patients had a LS ≥7.5 kPa. Mean of APRI, Forns, and FIB4 was 0.29 ± 0.11, 4.15 ± 1.63, and 1.16 ± 0.59, respectively. FS did not differ between the patients with LS <7.5 kPa and those with LS ≥7.5 kPa. Italians displayed a significant lower ALT (0.53 ± 0.18 vs. 0.67 ± 0.33, p < 0.05) and AST (0.59 ± 0.16 vs. 0.70 ± 0.21, p < 0.01) value than foreigners. No differences in LS and HBV-DNA levels were observed. In 66 patients followed up for 24 months, HBV-DNA increased by ≥2000 UI/ml after 12 months in 15 individuals and remained ≥2000 UI/ml after 24 months in 10/15 individuals. 7/10 patients showed LS ≥ 7.5 kPa after 24 months, and 4 of them underwent antiviral therapy for HBV. Patients with HBV-DNA <2000 IU/ml had a significantly lower LS than those with HBV-DNA ≥2000 IU/ml (5.30 ± 1.43 vs. 7.69 ± 1.07, p < 0.0001). Conclusions: Analysis shows lower effectiveness of FS vs. TE in the assessment of putative inactive HBV carriers. Furthermore, using FibroScan® and HBV-DNA can identify "false" inactive carriers.