The relationship of hepatotoxic risk factors and liver histology in methotrexate therapy for juvenile rheumatoid arthritis

Objective: To examine the relationship between hepatotoxic risk factors and liver histopathology in patients with juvenile rheumatoid arthritis (JRA) treated with methotrexate (MTX). Study design: We graded the histology of 33 percutaneous liver biopsy specimens from 25 patients with JRA treated at Children’s Hospital Medical Center, Cincinnati, Ohio, using the Roenigk Classification Scale. Stepwise linear and logistic regression analyses were performed to examine the relationship of the Roenigk grade and presence of liver fibrosis of biopsy specimens with potential risk factors. Results: Twenty-seven biopsy specimens (82%) were classified as grade I, 4 (12%) as grade II, and 2 (6%) as grade IIIA; none demonstrated significant fibrosis. The frequency of biochemical abnormalities (P < .001) and body mass index (P = .05) were the only risk factors found to significantly relate to the Roenigk grade. The following factors were not significantly associated with the Roenigk grade: age, gender, disease duration, JRA subtype and course, duration of MTX administration, weekly MTX dose, cumulative dose of MTX, route of MTX administration, use of folic acid supplementation, concurrent use of other medications, and potential hepatotoxic comorbidities. Conclusions: Serial biochemical abnormalities are significantly associated with Roenigk grade and the presence of liver fibrosis. These findings concur with studies of patients with rheumatoid arthritis, suggesting that guidelines for monitoring MTX hepatotoxicity in rheumatoid arthritis may be applicable to patients with JRA. (J Pediatr 1999;134:47-52)