Paget's Disease of Bone

Paget's disease of bone is a chronic disorder that can result in enlarged and misshapen bones. The excessive breakdown and formation of bone tissue causes affected bone to weaken, resulting in pain, misshapen bones, fractures, and arthritis in the joints near the affected bones. Paget's disease typically is localized, affecting just one or a few bones, as opposed to osteoporosis, for example, which usually affects all the bones in the body. Decisions about treating Paget's disease can be complicated because 1) no two people are affected in exactly the same way by the disease, and 2) it is sometimes difficult to predict whether a person with Paget's disease who shows no signs of the disorder will develop symptoms or complications (such as a bone fracture) at a later date. Although there is no cure for Paget's disease, medications (bisphosphonates and calcitonin) can help control the disorder and lessen pain and other symptoms. Paget's disease experts recommend that these medications be taken by people with Paget's disease who

• have bone pain, headache, back pain, or a nerve-related symptom (such as "shooting" pains in the leg) that is directly associated with the disease;
• have elevated levels of serum alkaline phosphatase (ALP) in their blood;
• display evidence that a bone fracture will occur;
• require pretreatment therapy for affected bones that require surgery;
• have active symptoms in the skull, long bones, or vertebrae (spine);
• have the disease in bones located next to major joints, placing them at risk of developing osteoarthritis;
• develop hypercalcemia that occurs when a person with several bones affected by Paget's disease and a high serum alkaline phosphtase level is immobilized.

Today's medications, especially when started before complications begin, are often successful in controlling the disorder. Paget's disease is rarely diagnosed in people less than 40 years of age. Men are more commonly affected than women (3:2). Prevalence of Paget's disease ranges from 1.5 to 8.0 percent, depending on age and country of residence. Prevalence of familial Paget's disease (where more than one family member has the disease) ranges from 10 to 40 percent in different parts of the world. Because early diagnosis and treatment is important, after age 40, siblings and children of someone with Paget's disease may wish to have an alkaline phosphatase blood test every two or three years. If the alkaline phosphatase level is above normal, other tests such as a bone-specific alkaline phosphatase test, bone scan, or X-ray can be performed.