Assessment of liver fibrosis by transient elastography and procollagen III amino terminal propeptide in rheumatoid arthritis patients treated with methotrexate

Abstract Background Methotrexate (MTX) is well known as the first-line therapy for rheumatoid arthritis (RA) patients. Its prolonged usage necessitates frequent assessing for adverse impacts, most importantly hepatotoxicity. Since there are no set standards for verifying liver damage in RA patients; transient elastography (TE) is emerged as a non-intrusive technique for identifying and evaluating liver fibrosis, alongside with serum procollagen III amino terminus propeptide (PIIINP). The objective of this study is to investigate liver fibrosis in 60 patients with RA patients on MTX therapy and 30 healthy individuals by TE and PIIINP, in addition, to recognize the prognostic indicators for liver fibrosis. Results This study compared 60 adult RA patients who had been on MTX for at least 1 year to 30 matched age and sex heathy individuals. Liver fibrosis was measured using TE and PIIINP. A cutoff point of 7.1 kPa was declared abnormal, suggesting substantial liver fibrosis, while PIIINP > 170 ng/ml indicating elevated PIIINP levels. Based on TE results, liver fibrosis was reported in 20 patients (33.3%) with 14 patients (23.3%) who had significant liver fibrosis, 4 patients (6.7%) had advanced liver fibrosis, and 2 patients (3.3%) had liver cirrhosis. Meanwhile, five of the controls had mild liver fibrosis with highly statistically significant difference between patients and controls. The patient group had significantly higher level of PIIINP when compared to the healthy group with a specificity and sensitivity for detecting liver fibrosis of 85% and 82.5%, respectively. Conclusions MTX usage in RA patients was correlated with an overall increase in liver fibrosis. Cumulative dosage of MTX, the presence of fatty liver and elevated serum PIIINP levels are all significant predictors of liver stiffness in RA. TE is organ specific and could be helpful in assessing true liver status rather than PIIINP level which is not organ specific. TE is superior to serum PIIINP and is recommended as a routine investigation for RA patients on MTX therapy particularly those with fatty liver.