Etanercept In the treatment of AA-amyloidosis in juvenile rheumatoid arthritis

Abstract

Objective. To study effect of etanercept, an antagonist of serum A amyloid production in the AA amyloidosis treatment in juvenile idiopathic arthritis (JIA). Material and methods. Etanercept was administered to all pts with AA amyloidosis admitted to Garmisch-Paterkirchen pediatric rheumatological clinic beginning with 2000. C-reactive protein (CRP), degree of proteinuria and serum creatinin were used as preliminary outcome measures. Results. 11 pts with seronegative JIA (6 boys and 5 girls) were included in the study. Mean follow up duration was l,9±l.01 years. 8 children had systemic, 2 - olygoarticular and one - polyarticular disease onset. Before the study all pts had CRP level elevation (1,03-8,29 mg/dl, mean 4,53 mg/dl). 8 from 11 had marked proteinuria (364-7400 mg/24 hours, mean 1186 mg/24 hours). 2 from 11 had serum creatinin elevation. During etanercept treatment CRP level normalized in 2 and significantly decreased in 4 pts. Proteinuria decreased in 4 from 8 pts. Significant change of creatinin level was not achieved. One girl who did not have improvement during etanercept treatment showed CRP normalization and decrease of proteinuria when the drug was changed to infliximab. Conclusion. Treatment with etanercept provided improvement in almost 2/3 from 11 pts with JIA and AA amyloidosis. Etanercept may be the drug of choice in pts with normal creatinine level in the absence of proteinuria. When it fails another tumor necrosis factor antagonist such as infliximab should be used. It is necessary to extend volume and duration of the study to get more reliable data on etanercept efficacy in JIA pts with AA amyloidosis.