Pagets Disease: A Comprehensive Guide

Epidemiology

Demographics:

• Peak incidence in the 5th decade of life
• Common in Caucasians (northern European / Anglo-Saxon descent)
• Males = females

Anatomic location:

• May be monostotic or polyostotic
• Common sites include femur, pelvis, tibia, skull, and spine

Etiology

Pathophysiology:

• Increased osteoclastic bone resorption is the primary cellular abnormality
• Cause is thought to be a slow virus infection (intra-nuclear nucleocapsid-like structure)
• Paramyxovirus
• Respiratory syncytial virus

Genetics:

• Most cases are spontaneous
• Hereditary
• Familial clusters have been described with ~40% autosomal dominant transmission

Clinical Presentation

Most patients with Paget's disease are asymptomatic. Symptomatic patients may present with:

• Bone pain
• Fractures
• Deformities
• Headache
• Hearing loss
• Neurologic symptoms (if spinal involvement)

Diagnosis

Diagnostic tests:

• Alkaline phosphatase (ALP) level: Elevated in up to 90% of patients (marker of increased bone turnover)
• X-rays: Show a widened bone and areas of sclerosis
• Bone scan: Shows increase in activity and uptake
• Biopsy: Not usually needed for diagnosis, reserved for atypical cases or suspicion of malignancy

Treatment

Non-pharmacological:

• Physical therapy for pain relief and to strengthen muscles around affected bones
• Assistive devices (cane, walker) for mobility and to reduce risk of falls
• Weight-bearing exercises to maintain bone strength

Pharmacological:

• Bisphosphonates (e.g. alendronate, risedronate) to reduce bone resorption
• Calcitonin to inhibit bone resorption
• Pain medications (NSAIDs, acetaminophen) for pain relief

Prognosis

With appropriate treatment, most patients with Paget's disease have a good prognosis and can live normal lives. However, complications such as fractures and deformities can occur if the disease is not properly managed.