Comprehensive Approach to Detect Liver Fibrosis by Indirect Serum Biomarkers

The diagnostic accuracy of three serum-derived markers-aspartate aminotransferase-to-platelet ratio index (APRI), Fibrosis-4 (FIB-4), and the aspartate aminotransferase-to-alanine aminotransferase (AST/ALT) ratio-was investigated as noninvasive alternatives in this study for assessing liver fibrosis severity and correlating these scores with FibroScan-derived liver stiffness measurements in patients with chronic liver disease (CLD).

We enrolled 100 adult patients with a confirmed diagnosis of CLD for this cross-sectional analysis at GMC Kota. Consenting patients received clinical evaluations, ultrasound, and biochemical screenings [complete blood count (CBC), liver function tests (LFTs), glucose, and viral serology]. We staged liver stiffness (F0-F4) via FibroScan and computed indirect indices, including FIB-4, APRI, and AST/ALT, using validated equations.

The average participant age was 47 years, with males comprising 67% of the study population. FibroScan showed that 73% of patients had F4 fibrosis, followed by F3 (10%), F2 (12%), and F0-F1 (5%). Etiologies included alcohol-related liver disease (34%), hepatitis B (15%), hepatitis C (4%), autoimmune hepatitis (2%), and diabetes-associated nonalcoholic fatty liver disease (NAFLD) (38%). Significant positive correlations were found between liver stiffness and the AST/ALT ratio (r = 0.658), APRI (r = 0.639), and FIB-4 (r = 0.444), all with p < 0.0001. Diagnostic thresholds revealed that lower cutoff values (e.g., APRI > 0.5, FIB-4 ≥ 1) had high sensitivity, whereas higher cutoff values (e.g., AST/ALT > 1, APRI ≥ 1, FIB-4 ≥ 3.24) achieved excellent specificity. A stepwise diagnostic approach using these thresholds improved detection accuracy and reduced reliance on liver biopsy.

The study validates simple, cost-effective biomarkers as reliable tools for fibrosis detection. Their integration into clinical practice may enhance early diagnosis, optimize resource use, and improve outcomes in patients with CLD, especially in low-resource settings.