Takayasu arteritis (TAK) is often associated with other inflammatory diseases. Here, we describe two Japanese patients with TAK complicated by synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome. Both patients presented with anterior chest pain as their chief complaint and were diagnosed with TAK following SAPHO syndrome. Treatment with glucocorticoids and biological agents led to a rapid improvement in symptoms. A review of the literature identified 11 additional cases of TAK complicated by SAPHO syndrome. SAPHO syndrome frequently precedes TAK, with the diagnostic interval between the two diseases ranging from 1 month to 12 years. No clear association was found between the sites of osteoarticular and vascular involvement. These findings suggest that SAPHO syndrome may be a comorbid condition in patients with TAK. As TAK may develop several years after the diagnosis of SAPHO syndrome, clinicians should consider the possibility of TAK in patients presenting with severe inflammation that cannot be fully explained by SAPHO syndrome alone.
