Radiologic analysis of the effect of tocilizumab on hands and large joints in children with systemic juvenile idiopathic arthritis

Abstract

Objectives: To assess the efficacy of tocilizumab for preventing damage to the joints of systemic juvenile idiopathic arthritis (sJIA) patients, we examined serial radiographs of the hands and large weight-bearing joints of these patients before and after treatment with this agent.

Methods: Nine patients with sJIA receiving 8 mg/kg of tocilizumab intravenously every 2 weeks were studied. The mean follow-up period was 82 months. The number of active joints and laboratory markers of inflammation were assessed before and after tocilizumab treatment, together with radiologic evaluation of the hips, knees, ankles, shoulders, and elbows. The latter examination included soft tissue swelling, juxta-articular osteoporosis, epiphyseal irregularity, joint-space narrowing, cyst formation, erosion, and localized growth abnormalities. Modified Larsen scores for the large joints and the Poznanski score were also recorded.

Results: After tocilizumab treatment, the number of active joints and serum inflammatory markers decreased (p < 0.01). There was a decrease in radiologic abnormalities at the final follow-up (p < 0.01) with the exception of localized growth abnormalities. Radiologic improvement was observed in 47 joints (52%), but ten (11%) worsened. Total Larsen score was decreased from 15.8 to 10.9 at the final follow-up. Although the Poznanski score did not change after tocilizumab treatment, it was closely correlated with the total Larsen score (r = 0.53, p < 0.05).

Conclusions: We describe radiologic improvement of the majority of damaged large joints in sJIA following tocilizumab therapy, but some deteriorated further despite stabilization of systemic inflammatory responses. Further studies with a larger number of patients are needed.