Clinical analysis of the initial symptoms among 164 synovitis, acne, pustulosis, hyperostosis, osteitis syndrome patients

Objective To explore the initial symptoms of synovitis, acne, pustulosis, hyperostosis, osteitis (SAPHO) syndrome, and to analyze the clinical and laboratory characteristics of these patients. Methods We retrospectively analyzed the initial symptoms of 164 patients diagnosed with SAPHO syndrome presented at Peking Union Medical College Hospital from 2004 to 2015, and their clinical, laboratory, and radiological data were collected. The t test, Mann-Whitney U test and chi-square test were used to compare the clinical differences between the SAPHO patients with different initial symptoms. Results Among the 164 patients recruited, 84(51.2%) had skin lesions before osteoarticular symptoms, whereas 29(17.7%) after and42(25.6%) simultaneously. Nine (5.5%) patients had no skin lesions. The time interval between onset of skin and osteoarticular lesions was less than 2 years in 133(81.1%) patients, but up to 35 years at most. Interestingly, a significantly higher age at onset was observed in patients with osteoarticular symptoms prior to skin lesions than those after [(41±10) years vs (36±11) years, t=-2.174, P=0.032]. Moreover, positive HLA-B27 was more frequently detected in patients having osteoarticular symptoms as the initial presentations (10.3% vs 0, P=0.016). Although treated more aggressively before baseline, patients presented with osteoarticular symptoms prior to skin lesions had significantly higher level of hs-CRP at baseline compared with those after [5.42(1.88, 12.70) mg/L vs 11.60(3.76, 22.08) mg/L, Z=-2.096, P=0.036]. Conclusion Skin lesions tend to appear prior to osteoarticular symptoms in most SAPHO syndrome patients. The percentage of patients who developed skin lesions after osteoarticular symptoms increase with age at onset. Key words: Acquired hyperostosis syndrome; Signs and symptoms; Skin manifestations