Two siblings with Paget's disease of bone

Paget's disease of bone (PDB) is a chronic disorder characterised by focal areas of excessive osteoclastic bone resorption with a secondary increase in osteoblastic bone formation. First-degree relatives of patients with PDB are at seven times higher risk of developing this disorder, with a tendency towards earlier age at onset. We report two siblings who presented with features of polyostotic Paget's disease. They presented with features of non-inflammatory back pain. Biochemical evaluation was unremarkable except for elevated serum alkaline phosphatase. Subsequently, radiology and bone scans were diagnostic of polyostotic PDB. They were treated with bisphosphonates with which they improved.