The role of liver biopsies in psoriatic patients receiving long-term methotrexate treatment. Improvement in liver abnormalities after cessation of treatment.

Liver biopsy specimens from 168 patients who underwent a total of 364 biopsies were examined. Of 83 patients receiving biopsies before methotrexate treatment, 14 had one or more risk factors predictive of liver abnormality but they had normal pretreatment biopsy specimens. Among 17 patients with abnormal biopsy specimens before methotrexate treatment, only 1 had an identifiable risk factor and 5 had abnormal results of liver function tests. The probability of a normal biopsy specimen after methotrexate treatment dropped below 50% at a cumulative methotrexate dose of 3115 mg for the 31 patients with biopsy specimens from before and after methotrexate treatment and 5776 mg for those who had biopsies only after methotrexate treatment; this difference was statistically significant and is thought to be related to the fact that the patients who had biopsies before and after methotrexate treatment had received most of their medication by the parenteral rather than the oral route. A significant association existed between biopsy grade after methotrexate treatment and obesity. Other risk factors were not correlated with biopsy grade. Blood chemistry tests were not predictive of histopathologic findings. Eight of 11 patients with fibrosis or cirrhosis showed meaningful improvement in liver histologic findings after methotrexate treatment had been withdrawn for 6 months or more; none had progression of abnormalities.