Background systemic juvenile idiopathic arthritis (sJIA) is an arthritis with systemic manifestations (fever, rash, lymphadenopathy, hepatosplenomegaly) in children up to 16 years. In juvenile arthritis often occur growth disorders. Prior to the widespread use of biologic agents in 10–20% of children with sJIA was noted growth retardation. Currently it is of importance to investigate the influence of biologic agents on growth.
Objectives To evaluate the effect of tocilizumab (TCZ) the growth of children with sJIA.
Methods the study included 25 children with sJIA, all children with high clinical and laboratory activity. All patients received active anti-rheumatic therapy, including therapy with glucocorticoids (GC): all patients (100%) – pulse therapy; oral - 12 children (48%). The age of the onset was 6,2±2,4years (from 9 months to 13,6years). 9 children (36%) before tocilizumab received anti-rheumatic therapy, 5 (20%) children – another biological agent. The duration of such therapy was 2,9±2,9 years (1 month to 12 years), 11 children (44%) began receiving tocilizumab during the year from the onset of the disease. The average age of initiation: 9,4±3,4 years (4 to 14 years old). The study evaluated growth SDS, growth rate and growth rate SDS prior of the therapy with tocilizumab after 6 months, after 1 year and after 2 years of therapy.
Results In 22 children (88%) with sJIA prior TCZ growth SDS was normal: -0,03±1,2 (-1,4 to 2,6). In 3 patients (12%) identified growth retardation: growth SDS from -2,6 to -6,0. These children were transferred tocilizumab via 7,6±3,0 years from the onset of the disease.
After 6 months of TCZ therapy in all children the average rate of growth amounted to 5,0±2,4 cm/yr, growth rate SDS was -0.2±2,4 (from -4,8 to 6,4). After 1 year growth rate was 6,5±3,2cm/yr, growth rate SDS was 2,5±2,8 (6,61 to -2.9). After 2 years of therapy growth rate amounted 6,5±2,5 cm/yr. Growth rate SDS on the 2nd year amounted to 2,8±2,8 (6,4 to -2,1).
In children previously treated with anti-rheumatic therapy and other biological agent, the average rate of growth prior to the TCZ initiation was 4,3±2,3 cm/year, growth rate SDS was -2,3±2,3 (-5,5 to 0,06). After 6 months of TCZ therapy growth rate was 5,9±2,8cm/year, growth rate SDS was 0,9±1,9 (-2,2 to 3,9). After 2 years of therapy growth rate was 6,1±3,1cm/year, growth rate SDS was 2.9±2,7 (from 1,7 to 6,2). Growth rate SDS was significantly higher than the previous one as after 6 months as after 2 years of TCZ therapy.
Growth SDS in all children after 2 years of TCZ therapy was -0,1±1,5 (-4,3 to 2,3). In children with growth retardation growth SDS has improved significantly -2,6 up to -1,7, -3,5 to -3,2, and -6,0 to -4,2 respectively.
Conclusions Treatment with tocilizumab increases growth rate not only in the first year, but in the subsequent period of treatment. Timely therapy sJIA with TCZ prevents growth retardation in children with normal growth and reduces existing growth retardation.
Uettwiller F., Perlbarg J., Pinto G./Effect of biologic treatments on growth in children with juvenile idiopathic arthritis. // J Rheumatol. 2014 Jan;41(1):128–35.
Acknowledgement The staff of rheumatologic department of Pediatric Clinic of 1st Medical state University named after Sechenov
Disclosure of Interest None declared