Endocrine Abstracts

Paget’s disease of bone is the second most common metabolic bone disease after osteoporosis. It is a condition characterised by abnormal bone cellular activity resulting in the formation of disorganised (and weaker) bone. Paget’s disease can affect single or multiple bones. In many cases it may be asymptomatic, however it can often be associated with pain affecting the pagetic bone or there may be ‘peri-pagetic’ pain related to altered biomechanics due to changes in bone shape or to stress put on adjacent joints leading to the development of osteoarthritis. The primary pathological change is an increase in bone turnover. This increase in turnover can be assessed by measurement of alkaline phosphatase which often correlates with both the extent of the pagetic bone load and the degree of pagetic activity. Aside from pain, Paget’s disease can be associated with a variety of complications. These include bone deformity and fractures, compressive neurological problems leading to e.g. spinal stenosis and deafness. Cardiovascular and metabolic complications are rare and transformation to osteosarcoma is particularly rare. The primary aims of treatment are to manage pain and/or associated complications. Antiresorptive treatment is the mainstay of therapy with IV zoledronic acid being the treatment of choice. Antiresorptive therapy will both reduce bone vascularity and be associated with falls in alkaline phosphatase. There has been some recent interest in other bone turnover markers as tools to assess pagetic activity however the role for these markers remains uncertain. It had been hoped that aggressive targeting of alkaline phosphatase suppression might be associated in less in the way of longer-term pagetic complications but data from PRISM and PRISM-EZ studies suggest this approach is probably not beneficial.