A pediatric patient with prolonged seronegative polyarticular juvenile idiopathic arthritis (JIA) and concomitant aggressive, anterior uveitis refractory to any conventional antirheumatic therapy was treated with infliximab. Arthritis and C-reactive protein (CRP) values showed prompt positive effects but, after 6 weeks, returned gradually to initial values despite ongoing therapy. In contrast, a more sustained therapeutic effect was observed on the uveitis, with increased visual acuity and reduced inflammatory signs of the affected eye. However, this benefit was also lost at week 30, after which infliximab had to be discontinued due to side effects. To conclude, in polyarticular seronegative JIA, infliximab showed a transient beneficial effect which was more pronounced on uveitis than arthritis.