Paget's disease of bone.

Paget's disease of bone is a focal disorder of bone remodeling accompanied initially by an increase in bone resorption, followed by a disorganized and excessive formation of bone, leading to pain, fractures and deformities. It exhibits a marked geographical variation in its prevalence. In Brazil it predominantly affects persons of European descent. The majority of the reported cases of the disease in Brazil are from Recife, owing to its peculiar mixed European colonization over approximately four centuries. The etiology is complex and involves both genetic and environmental factors. The disease is often asymptomatic and diagnosis is usually based on biochemical markers of bone turnover, radionuclide bone scan and radiological examination. Bisphosphonates, in particular zoledronic acid, are regarded as the treatment of choice for Paget's disease of bone.