Paget's disease
This is the second most frequent bone disorder, following osteoporosis. It affects 1.5-3% of the population over 65 years of age. It was described by Sir James Paget in 1876. In this disease, the natural process of the destruction of old bone and the formation of new bone (called bone remodelling) is abnormal and disordered. As a consequence, the bone is fragile, it increases in size, and it presents deformity. Thus, it also receives the name of deforming osteitis. It usually affects the cranium, spinal column, and the pelvis. The risk of having this disease increases with age, and it is very rare in young people.
Causes
The underlying cause is not known for sure, but it's known to have an important genetic and family component. Thus, the probability of suffering this disease increases if family member has it. It could also be associated with a viral infection like measles or rubella.
Symptoms and diagnosis
It usually does not produce symptoms. In fact, the diagnosis is usually made based on an unusually high alkaline phosphatase level or findings suggestive of the disease on imaging tests that were ordered for another reason. However, it can cause pain in the affected area that does not improve with rest due to the increase in bone, as well as redness and heat secondary to the increased number of blood vessels in that area. If it affects a joint, it can cause arthrosis. If it compresses nerve roots, it can cause sciatica or even deafness (if the head is affected). It can also cause fractures. A rare complication is the degeneration into bone cancer (osteosarcoma).
Bone scintigraphy is the nuclear medicine technique that reveals which bones are affected by the disease.
Treatment
The medical treatment includes pharmaceuticals to improve pain (analgesics and anti-inflammatory agents) and pharmaceuticals that inhibit bone remodelling, such as biphosphonates (zoledronat, alendronat), which are widely used for osteoporosis. Measures to improve quality of life, such as using a cane if arthrosis is present or using hearing aids if the illness has caused deafness, are very important. If a bone or joint is a severely affected, surgery can be considered. In general, the illness responds well to treatment and has a good prognosis.
