Paget’s Disease of Bone (PDB) Flashcards
What is Paget’s Disease of Bone (PDB)?
Chronic disease characterized by abnormal bone remodeling
First described by Sir James Paget in 1876 as osteitis deformans.
What are the pathological features of PDB?
Overactive, enlarged osteoclasts leading to excessive bone resorption and compensatory osteoblast activity causing disorganized, weak bone.
What factors are believed to cause Paget’s Disease of Bone?
Unknown, likely involves genetic and environmental factors
Genetic factors include mutations in SQSTM1 gene.
Which gene mutations are associated with familial cases of PDB?
Mutations in the SQSTM1 gene (40–50% of familial cases).
What is the epidemiological trend of PDB?
Decreasing incidence worldwide; more common in older adults (>40 years), men, and individuals of European descent.
What percentage of PDB cases are asymptomatic?
60–70% of cases are asymptomatic.
What are common symptoms of PDB?
Bone pain, skeletal deformities, fractures, osteoarthritis.
What laboratory test is elevated in PDB?
Elevated serum alkaline phosphatase (ALP).
What are the common sites of bone involvement in PDB?
Pelvis, femur, lumbar spine, skull, tibia.
What are the three phases of disease progression in PDB?
- Osteolytic Phase 2. Mixed Phase 3. Sclerotic Phase.
Describe the Osteolytic Phase of PDB.
Increased osteoclast activity leading to bone resorption and radiographic findings of bone loss, lytic lesions.
What is the most sensitive imaging technique for detecting PDB lesions?
Bone Scan.
What is the first-line therapy for PDB?
Bisphosphonates.
Name a bisphosphonate that is considered the most effective for PDB.
Zoledronate (IV).
What are indications for treatment of PDB?
Bone pain, high risk of complications, pre-surgical preparation, hypercalcemia during immobilization.
What are common side effects of bisphosphonate therapy?
Acute-phase response, esophagitis, dyspepsia, hypocalcemia, rare osteonecrosis of the jaw, atypical femoral fractures.
What are the complications associated with PDB?
Osteoarthritis, fractures, pseudofractures, bone deformities, neurologic issues, rare high-output cardiac failure, hypercalcemia, osteosarcoma.
What is the risk of osteosarcoma in PDB?
Rare (<1% of PDB cases).
What symptoms may indicate osteosarcoma in a patient with PDB?
Increased pain, swelling, new mass, or fracture at pagetic site.
How is PDB diagnosed?
Based on elevated ALP and radiographic findings.
What is the prevalence of PDB in U.S. adults over 55 years?
2–3%.
What are the common laboratory tests for PDB?
ALP, calcium, albumin, liver function tests, 25-OH vitamin D.
Fill in the blank: The most common site of bone involvement in PDB is the _______.
Pelvis.
True or False: PDB is more common in women than men.
False.
