Basic fibroblast growth factor: a marker predicting the severity of joint destruction in juvenile rheumatoid arthritis

ABSTRACT

To investigate whether serum basic fibroblast growth factor [bFGF], as a representative of angiogenesis, is to be considered a useful marker for predicting joint destruction in juvenile rheumatoid arthritis [JRA]. bFGF was measured by ELISA in 30 serum samples and 8 joint fluid samples obtained from JRA patients. Patients were evaluated at baseline and 12 months later. A] Clinically with the overall articular severity score. B] Laboratory tests including ESR, complete blood count and rheumatoid factor. C] Radiologically using modified Larsen index, mal-alignment and van Rossum's scores. A group of 20 healthy children and another of 10 patients with other collagen vascular diseases were also studied for comparison. Serum bFGF was significantly higher in JRA patients than those with other collagen vascular diseases and the controls with 90% sensitivity and 100% specificity at a cut-off level of 0.203 pg/ml [control mean + 3SD]. Polyarticular JRA patients had a significant higher rate of positive bFGF than those with systemic onset or pauciarticular types. Synovial fluid bFGF levels were significantly higher than the corresponding serum values. Serum bFGF correlated positively with disease activity markers and the articular severity score. Radiological evaluation revealed higher rate of seropositive bFGF in patients with severe joint destruction than in those with mild form of joint affection. Moreover, patients whose serum bFGF levels were >0.231 pg/ml showed deterioration of the clinical and radiological scores of joints when reevaluated after one year. Serum bFGF concentration helps to assess the degree of joint involvement and is a useful prognostic marker for predicting the severity of joint destruction in JRA patients