@article {Masi986, author = {Laura Masi and Gabriele Simonini and Elisabetta Piscitelli and Francesca Del Monte and Teresa Giani and Rolando Cimaz and Silvia Vierucci and Maria Luisa Brandi and Fernanda Falcini}, title = {Osteoprotegerin (OPG)/RANK-L system in juvenile idiopathic arthritis: is there a potential modulating role for OPG/RANK-L in bone injury?}, volume = {31}, number = {5}, pages = {986--991}, year = {2004}, publisher = {The Journal of Rheumatology}, abstract = {OBJECTIVE: To evaluate serum levels of osteoprotegerin (OPG) and receptor activator of nuclear factor kB-ligand (RANK-L) in patients with juvenile idiopathic arthritis (JIA); to correlate these values with disease activity variables, radiological bone damage, and bone mass; and to correlate OPG gene polymorphisms with bone mass. METHODS: Eighty-four patients (66 girls and 18 boys) with JIA and 40 sex and age-matched controls were enrolled. Serum OPG and RANK-L were measured using an enzyme-linked immunosorbent assay. OPG genotyping was performed by polymerase chain reaction. RESULTS: Patients with JIA had significantly higher levels of serum OPG than controls (p = 0.001) and lower levels of RANK-L in comparison with controls (p = 0.0003). The OPG/RANK-L ratio in patients was higher than in controls (p = 0.004). No significant correlations were found between disease duration, erythrocyte sedimentation rate, and C-reactive protein values with either OPG or RANK-L serum levels. A significant difference in serum OPG levels (but not in RANK-L) was found between patients with and without erosions (p = 0.008). No correlation was found between OPG and RANK-L levels and bone mass (DXA Z scores). A higher prevalence of OPG CC genotype was found in both patients (65.4\%) and controls (82.5\%) (p = 0.006). Subjects with CC genotype had a higher lumbar spine bone mineral density (LS-BMD). CONCLUSION: We evaluated for the first time levels of OPG and RANK-L in children with JIA. The higher OPG/RANK-L ratio in JIA might be the result of a compensatory production of OPG. The presence of the T allele of the OPG gene appears to be associated with low BMD.}, issn = {0315-162X}, URL = {https://www.jrheum.org/content/31/5/986}, eprint = {https://www.jrheum.org/content/31/5/986.full.pdf}, journal = {The Journal of Rheumatology} }