Biopsy or biochemistry? the monitoring of hepatic fibrosis from methotrexate

ABSTRACT

Hepatic fibrosis is an important consequence of inflammatory disorders affecting the liver, and ultimately progresses to cirrhosis. Here we explore methods for the detection and monitoring of hepatic fibrosis, particularly during methotrexate therapy, in which progressive fibrosis can develop over a number of years in a minority of patients. Liver biopsy remains currently the gold standard to assess fibrosis. However, it has several limitations, including manpower issues, cost, risk of patient injury, including mortality and morbidity, observer variability and sampling variation. Several non-invasive diagnostic tests for fibrosis and cirrhosis have therefore been evaluated. The usefulness of a laboratory test for screening for a pathological abnormality such as fibrosis is critically dependent on the prevalence of the pathology in the population under investigation. When the prevalence is expected to be low, screening tests should have a high negative predictive value, so that large numbers of patients can be spared the next diagnostic step, namely liver biopsy. For the moment, clinicians should use the aspartate aminotransferase [AST] / alanine aminotransferase [ALT] ratio and the AST/platelet [APRI] ratio for monitoring the development of hepatic fibrosis