Paget's disease of bone, also known as osteitis deformans, is a chronic condition characterized by abnormal bone remodeling that results in bone enlargement and deformity. The exact cause of Paget's disease is not well understood, but it is believed to be related to a viral infection or genetic factors.

Symptoms of Paget's disease can vary, but may include:

• Bone pain
• Bone deformity
• Fractures
• Hearing loss
• Headaches
• Numbness or tingling in the limbs
• Arthritis
• Bowing of the legs

Diagnosis of Paget's disease is typically made based on a combination of clinical symptoms, radiographic imaging, and laboratory tests, including blood tests to assess bone turnover markers.

Treatment of Paget's disease may involve medications to regulate bone turnover and reduce the risk of complications such as fractures, pain, and deformity. These may include bisphosphonates, calcitonin, or other medications that can help to slow down the bone remodeling process. In severe cases or when complications occur, surgery may be necessary.

Prevention of Paget's disease is not currently possible, as the underlying cause is not fully understood. However, early detection and treatment can help to manage symptoms and prevent complications. It is important for individuals who are at risk for Paget's disease, such as those with a family history or who have had previous bone fractures, to discuss screening and prevention strategies with their healthcare provider.

The cause of Paget's disease of bone is unknown. Scientists suspect a combination of environmental and genetic factors contribute to the disease. Several genes appear to be linked to getting the disease.

Some scientists believe Paget's disease of bone is related to a viral infection in your bone cells, but this theory is controversial.

If you don't have symptoms, you might not need treatment. However, if the disease is active — indicated by an elevated alkaline phosphatase level — and is affecting high-risk sites in your body, such as your skull or spine, your doctor might recommend treatment to prevent complications, even if you don't have symptoms.

Medications

Osteoporosis drugs (bisphosphonates) are the most common treatment for Paget's disease of bone. Bisphosphonates are typically given by injection into a vein, but they can also be taken by mouth. When taken orally, bisphosphonates are generally well tolerated but can irritate the stomach.

Bisphosphonates that are given intravenously include:

• Zoledronic acid (Zometa, Reclast)
• Pamidronate (Aredia)
• Ibandronate (Boniva)

Oral bisphosphonates include:

• Alendronate (Fosamax, Binosto)
• Risedronate (Actonel, Atelvia)

Rarely, bisphosphonate therapy has been linked to severe muscle, joint or bone pain, which might not resolve when the medication is discontinued. Bisphosphonates can also increase the risk of a rare condition in which a section of jawbone dies and deteriorates, usually associated with active dental disease or oral surgery.

If you can't tolerate bisphosphonates, your doctor might prescribe calcitonin (Miacalcin), a naturally occurring hormone involved in calcium regulation and bone metabolism. Calcitonin is a drug that you administer to yourself by injection or nasal spray. Side effects may include nausea, facial flushing and irritation at the injection site.

Surgery

In rare cases, surgery might be required to:

• Help fractures heal
• Replace joints damaged by severe arthritis
• Realign deformed bones
• Reduce pressure on nerves

Paget's disease of bone often causes the body to produce too many blood vessels in the affected bones, increasing the risk of serious blood loss during an operation.

If you're scheduled for surgery that involves bones affected by Paget's disease of bone, your doctor might prescribe medications to reduce the activity of the disease, which may help reduce blood loss during surgery.