Twenty-nine children with cystic fibrosis (CF) were investigated for quinolone-induced arthropathy. Magnetic resonance imaging (MRI) was performed in 14/14 children treated with ofloxacin or ciprofloxacin and in 10/15 of those never treated with quinolones. The frequency of pathologic MRI findings, concerning cartilage thickness, careful analysis of the cartilage structure, presence of edema, cartilage-bone borderline and the presence of fluid in joints did not show any difference between both groups. Thus the presence of quinolone-induced arthrotoxicity cannot be confirmed in this study.