Immunosuppressive therapy and bone metabolism after kidney transplantation

The success of transplant medicine due to improvements of immunosuppressive therapy has led to a significant increase of patient and organ survival. With the increasing number of transplantations, however, long term complications, often affecting the skeletal system, are becoming more frequent. Bone alterations often exist prior to transplantation in patients with chronic renal failure. There are two types of renal osteopathy, including "low-turnover bone disease", consisting of osteomalacia, and adynamic bone disease, and "high-turnover bone disease" due to the development of secondary hyperparathyroidism. Many patients show evidence of both disorders (mixed bone disease). During the first months after transplantation patients lose bone mass rapidly. One of the major factors responsible for the development of osteoporosis is thought to be the intensive immunosuppressive therapy during that period, steroids in particular seem to play an important role. To what extent other medications influence bone metabolism has not been established. Currently there are no studies about a standardized therapy and treatment relies mainly on experience with other forms of osteoporosis.