Liver Elastography for the Detection of Methotrexate-Induced Liver Injury: A Retrospective Study

Abstract

Background: Liver biopsy, the gold standard for monitoring of methotrexate-induced liver injury, is associated with significant morbidity and mortality. Transient elastography (TE) has been used as a non-invasive alternative to detect liver stiffness. Aim: To assess the utility of TE in detecting liver fibrosis in patients with methotrexate use. Methods: A retrospective chart review was performed for 35 patients referred to the liver clinic for evaluation of suspected methotrexate-induced liver injury. Demographic, clinical, histopathological, and elastographic data were collected and interpreted. Liver stiffness measurement (LSM) and controlled attenuation parameter were recorded from TE results. Results: Thirty-five patients with a mean age of 58 years, including 23 females (66%), were included. The median LSM by TE was 10.8 kPa and the median controlled attenuation parameter was 303 dB/m. A total of 12 out of 35 patients (34%) had evidence of clinical and pathological advanced fibrosis. Using a cut-off elastography value of 10 kPa, the TE yielded 92% sensitivity and 93% negative predictive value for ruling out methotrexate-induced advanced liver fibrosis. Using a higher LSM cut-off point of kPa ≥15.0, specificity was calculated at 87% and positive predictive value at 80%. Area under the receiver operating characteristic curve was 0.80 (95% confidence interval). Conclusion: FibroScan® (Echosens, Paris, France) has a high sensitivity and specificity for kPa 10 and 15, respectively, for detecting advanced liver fibrosis in patients on methotrexate.