Increased levels of matrix metalloproteinase-3 in the sera and synovial fluids of patients with pustulotic arthro-osteitis associated with palmoplantar pustulosis: report of 2 cases

Pustulotic arthro-osteitis (PAO) is occasionally seen in patients with palmoplantar pustulosis (PPP); however, its pathogenesis is still obscure. Herein, two patients with PAO associated with PPP were described. Both patients developed hydrarthrosis on the knees, along with sternocostoclavicular pain. Detail examination revealed odontogenic infection in both cases. Matrix metalloproteinase-3 (MMP-3) is a useful marker reflecting the activity of rheumatoid arthritis. In this study, MMP-3 levels in the sera as well as joint fluids were examined. Serum MMP-3 levels were increased in both cases (274 ng/ml in Case 1 and 242 ng/ml in Case 2, normal; 17.3-59.7). Also, MMP-3 concentration in the joint fluids was markedly elevated (Case 1 > 80,000 ng/ml and 48,000 ng/ml in Case 2). Our studies suggest that MMP-3 may play a role in the pathogenesis of joint involvement of PPP.