Usefulness of the American College of Rheumatology recommendations for liver biopsy in methotrexate-treated rheumatoid arthritis patients.

OBJECTIVE

To test the usefulness and cost savings resulting from application of the new American College of Rheumatology (ACR) guidelines for assessing the risk for the development of clinically significant liver disease in rheumatoid arthritis (RA) patients treated with methotrexate (MTX).

METHODS

One-hundred twelve MTX-treated RA patients were prospectively followed up for MTX hepatotoxicity and underwent liver biopsies according to modified guidelines of the Psoriatic Task Force (PTF). All biopsies were graded according to the Roenigk classification. The new ACR recommendations were then retrospectively applied to test their usefulness and cost-effectiveness in this cohort.

RESULTS

Based on the PTF guidelines, 66 patients underwent liver biopsies; a total of 110 liver biopsies were performed. Two patients had biopsy-related complications. Five patients were found to have Roenigk grade IIIB or IV histologic abnormalities. The total cost for this group was $111,380. Applying the new ACR criteria, only 15 patients would have undergone liver biopsies; there would have been a total of 18 biopsies, with no complications. Four of the 5 patients with Roenigk grade IIIB or IV liver abnormalities would have been identified. One patient with insulin-dependent diabetes mellitus (IDDM) who was found to have cirrhosis (Roenigk grade IV) on liver biopsy as a result of use of the PTF guidelines would have been missed with use of the ACR guidelines. The total cost for the group receiving biopsies based on the ACR guidelines would have been $16,956. Overall, the new ACR guidelines had 80% sensitivity and 82% specificity and resulted in a cost savings of $1,430 per patient.

CONCLUSION

The new ACR guidelines on MTX monitoring and biopsy surveillance appear to be clinically useful and result in considerable cost savings. However, 1 IDDM patient with significant liver histologic abnormalities would have been missed. We suggest that IDDM be added to the ACR guidelines as a risk factor for MTX hepatotoxicity.