Significant Correlation Between Liver Stiffness, Liver Histology, and APRI Score

Abstract

Purpose: The role of liver biopsy as the gold standard in the evaluation of liver fibrosis has been challenged by the development of biological markers, such as the APRI índex and mechanical methods such as transient elastography. To determine the correlation between liver histology, transient elastography (TE), and the APRI index score in the evaluation of the grade of fibrosis and to ascertain the correlation between serum levels of ferritin, total cholesterol, triglycerides, and grade of liver steatosis in abdominal ultrasound with liver histology. Methods: Seventy-three patients were evaluated over a period of 18 months. These were all submitted to TE, blood tests, abdominal ultrasound and liver biopsy during a maximum intervalo of 6 months. Histology was classified according to the METAVIR score. Cut-off values established were: 7.1 kPa for F ≥ 2, 9.5 kPa for F ≥ 3, and 12.5 kPa for F=4. For APRI, o cut-off for significant fibrosis (F2-4) was 1.5. Correlations were calculated using the Pearson's exact test. Results: The average patient's age was 48 years ± 12 with a majority of men (60%). In 10% of the cases, an XL probe was used. The causes of liver disease were varied: 25% with chronic hepatitis C, 20% with NAFLD/NASH, 11% with chronic hepatitis B, 10% with alcoholic liver disease, among other causes. There is a significant correlation between METAVIR score and TE (p<0,001), between APRI and TE (p<0,001), and METAVIR and APRI (p<0,001). High levels of serum ferritin p=0.013) and low platelet count p=0.013) were associated with significant fibrosis. There were no significant correlations between METAVIR, levels of triglycerides and cholesterol, nor grade of steatosis in abdominal ultrasound. Conclusion: Liver histology, liver stiffness, and APRI index correlate significantly. Ferritin levels and platelet count correlate significantly with the stage of fibrosis.