Performance of low-cost noninvasive blood markers of liver cirrhosis in adults with chronic hepatitis B infection with and without comorbid alcohol use in Zambia: A cross-sectional hospital-based study

Diagnosing liver cirrhosis in patients with chronic hepatitis B (CHB) remains challenging due to the infrequent use of biopsy. In low-and-middle-income countries, access to transient elastography (TE), a recommended noninvasive imaging modality for cirrhosis assessment, is limited. It is against this backdrop that we investigated the diagnostic performance of several low-cost and readily accessible blood-based liver fibrosis markers among patients with CHB infection in Zambia. We performed a hospital-based cross-sectional study in Lusaka, Zambia, among consecutive treatment naive adults presenting at the university teaching hospital with CHB mono-infection (i.e., human immunodeficiency virus-negative). The reference test for cirrhosis was TE of ≥9.6 kilopascals. Low-cost markers were the aspartate transaminase-to-platelet ratio index (APRI) at the recommended threshold >2, as well as lower proposed alternative thresholds for Africa, >0.5 and >0.65, aspartate transaminase/alanine transferase ratio, and fibrosis 4 index (FIB-4 index) >3.25. We evaluated the performance of each marker versus TE. In a secondary analysis, we evaluated marker performance in participants with current alcohol use versus lifetime abstinence. A total of 239 adults with HBV mono-infection were included in this analysis. The mean age was 34.7 years. About 22.2% (n = 53) reported current alcohol use. The prevalence of cirrhosis by TE was 16.3% (95% confidence interval: 11.87-21.63). The area under the receiver operating characteristic curve was 0.83, 0.80, 0.79 and 0.73 for FIB-4, APRI >0.5, APRI >0.65, and APRI >2, respectively. Virtually all indices performed less well in people with current alcohol use. These findings suggest the use of a lower APRI threshold in African settings and the use of the FIB-4 index for diagnosing cirrhosis among patients with CHB. The currently recommended APRI threshold may fail to identify some individuals with cirrhosis who would benefit from antiviral treatment. Clinicians using these markers should routinely screen for alcohol use and consider reevaluating cirrhosis status following reductions in alcohol consumption.