Efficacy of bisphosphonates in patients with synovitis, acne, pustulosis, hyperostosis, and osteitis syndrome: a prospective open study

OBJECTIVES: To evaluate the clinical efficacy of bisphosphonates treatment for spinal bone marrow oedema (BME) in patients with synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome. METHODS: SAPHO syndrome patients presenting to Peking Union Medical College Hospital from 2015 to 2016 were recruited. Patients were administered pamidronate disodium 1 mg/kg/d intravenously, for 3 days, at baseline and 3 months later. The symptoms were evaluated using the Visual Analog Score (VAS) for pain, and other clinical measures including, spinal BME scores, β-crosslaps, osteocalcin, and inflammatory factors, were collected. RESULTS: A total of 30 patients (20 women and 10 men) with a median age of 47.2 (interquartile range 8.8) years were recruited. In a short time, the patients showed a significant decrease in VAS (before vs. after; first treatment: 5.70±1.62 vs. 2.30±1.29 cm, second treatment: 4.03±1.88 vs. 2.17±1.23 cm) and β-crosslaps (first treatment: 0.4441±0.1923 vs. 0.0859±0.0374 pg/ml, second treatment: 0.2891±0.1983 vs. 0.0962±0.0324 pg/ml) (all p<0.05). At 12-month follow-up, compared with the baseline, we noticed a significant drop in the VAS (5.70±1.62 vs. 2.43±1.25 cm), erythrocyte sedimentation rate (28.87±25.26 vs. 18.00±18.65 mm/h), high-sensitivity C-reactive protein level (11.76±10.19 vs. 5.84±5.88 mg/L), osteocalcin (2.30±1.27 vs. 1.65±0.80 ng/ml), and BME (30.50±24.09 vs. 22.13±27.79) (all p<0.05). No one had serious adverse events. CONCLUSIONS: Bisphosphonates can significantly and rapidly relieve symptoms in patients with SAPHO syndrome and have a long-term effect on inflammation and spinal BME. We suggest that bisphosphonates could be used as the first-line therapeutic drug for SAPHO syndrome, especially in patients with spinal BME.