Paget disease of bone in Japanese patients: a report of three cases.

Paget disease of bone (PDB) is a bone metabolic disorder causing pain, fractures, and deformity. Its incidence is estimated to be 1 to 2% in Caucasians older than 55 years, but in Asian populations the incidence is rare. We report on 2 female and one male Japanese patients aged 46 to 73 years with PDB. One patient had monostotic disease with pain around the shoulder and the other 2 were asymptomatic. All patients had elevated alkaline phosphatase (ALP) levels (range, 629-957 U/L). Two patients responded to oral bisphosphonate treatment and achieved normalised ALP levels and pain relief. One patient with polyostotic disease did not show any change in ALP levels. The diagnosis of the disease and the indications for bisphosphonate treatment are discussed.