Objectives: Pamidronate has recently been used in SAPHO syndrome due to its anti-osteoclastic effect. The aim of this study is to determine the usefulness of bone remodelling markers for determining the efficacy of pamidronate treatment.
Methods: Thirteen patients with SAPHO syndrome were treated with pamidronate. The treatment evaluation was done using a visual analogue scale (VAS) and also erythrocyte sedimentation rate, C-reactive protein, serum crosslaps (sCTX) and osteocalcin initially and after 3 months. A relevant clinical response was defined as an improvement in VAS of at least 40%.
Results: At 3 months, 7 of 13 patients had a good clinical response, as previously defined. Five of the seven patients maintained the good response over 6 months. Before the first perfusion 6 of the 13 patients had increased sCTX (upper 3250 pmol/l). In this small cohort we tried to analyse whether the increase in bone remodelling markers was associated with a good clinical response. In the responders group the mean levels of sCTX and osteocalcin at baseline were 6783.17 and 24.66, respectively, and in the non-responders group the levels were 2152 and 11.8, respectively. There was a significant difference in sCTX between the responders and the non-responders (P = 0.0044).
Conclusion: Infusion of pamidronate is effective in SAPHO in some patients. Increased sCTX might be a prognostic marker for a good clinical response but results have to be confirmed in a larger cohort.