Paget’s disease
Paget’s disease refers to the bone disease characterized by increased bone tissue resorption at a cellular level and disorganized formation of new bone tissue. The disorderly bone remodeling and chaotic construction of structurally abnormal bone weaken the bone, causing bone pain and bone deformity. Paget’s disease is also called osteitis deformans(1).
Studies by Van D. and Mortiers (2020) found that paget’s disease is more prevalent in Britain than Australia and North America (2). Van D. and Mortiers (2020) found an incidence rate of 0.3% among British men and women older than 55. The incidence rate is higher among the elderly, with 5.4% and 7.6% reported among women and men more aged than 85 years of age, respectively (2-3). From the studies mentioned above, men are slightly more affected than women of all ages.
The exact cause of Paget’s disease is unknown (4). In the opinion of Reid R., both genetic predisposition and environmental exposures contribute to the pathogenesis of Paget’s disease (5). Initially, in the course of the disease, the activity of the osteoclasts increases. Osteoclasts are bone cells that are involved primarily in bone resorption. The next pathological process is an increase in the action of the osteoblasts. Osteoblasts are large bone cells that lay down osteoid that later transforms into the mineralized bone. Osteoclasts are normal bone cells critical in bone physiology. However, in Paget’s disease, the osteoblastic activity progresses in a disorganized manner, leading to structurally abnormal, weak bone tissue. Reid R. describes that increased cellular activity of osteoblastic cells is accompanied by increased deposition of fibrous tissues and the formation of new blood vessels that replace the normal bone marrow (5). Replacement of normal bone marrow leads to increased bone density (6).
Patients with paget’s disease present with bone pain, deformity of the limbs and facial bones and fractures. Early disease may be asymptomatic (4). Clinical history and physical examination initially point to the condition, but a diagnosis is established radiologically and by laboratory tests. Skeletal survey radiographs, where x-rays of the skeletal system is obtained, is vital in diagnosis. Laboratory tests include assay of serum alkaline phosphatase, serum calcium level and aminotransferase. A radionuclide bone scan is recommended for assessment of the severity of the condition (7).
Treatment involves a multidisciplinary team of physicians, orthopedic surgeons and endocrinologists who assess the extent of disease and prescribe medication and procedures. Bisphosphonates and calcitonin are commonly prescribed to reduce osteoclast cells’ activity, thus inhibiting bone resorption (8). Klemm P. et al. (2020) recommend early initiation of bisphosphonates to prevent the development of any secondary complications of the disease (4). Surgical procedures aim to correct deformities and open bonny canals narrowed by the disease process, usually the cranial foramina (9).
In conclusion, early diagnosis and treatment of Paget’s disease helps prevent severe complications and is the therapy goal (10). Van D. and Mortiers (2020) have documented improving care in Europe for patients with Paget disease in the recent past. With early diagnosis and prompt treatment, the deformities from Paget’s disease are preventable and treatable.