The short-term changes of bone mineral metabolism following bone marrow transplantation

Organ transplantation is now the treatment of choice for many patients with life-threatening chronic diseases. A new set of side effects unique to these groups of patients has become recognized, and bone disease is one of these complications. However, little is known about the effects of myeloablative treatment followed by bone marrow transplantation (BMT) on bone mineral metabolism. We have prospectively investigated 31 patients undergoing BMT for hematologic diseases. Serum concentrations of calcium, phosphorus, creatinine, gonadotropins, sex hormones, and the biochemical markers of bone turnover were measured. The samples were collected before BMT and 1, 2, 3, 4, and 12 weeks, 6 months, and 1 year after BMT. Bone mineral density (BMD) was measured with dual-energy X-ray absorptiometry before BMT and 1 year after BMT. The serum carboxy-terminal cross-linked telopeptide of type I collagen increased progressively until 4 weeks after BMT. Thereafter, it began to decrease and reached basal values after 1 year. Serum osteocalcin decreased progressively until 3 weeks after BMT. After that, it increased and reached basal values after 3 months. No distinct differences were observed in the serum biochemical turnover markers between males and females, or between patients who received total body irradiation and those who did not. One year after BMT, lumbar spine BMD had decreased by 2.2%, and total proximal femoral BMD had decreased by 6.2%. Eighty-six percent of the women (12/14) went into a menopausal state immediately after BMT. This was caused by high gonadotropin levels and low estradiol levels. In contrast, gonadotropin levels and testosterone levels did not change significantly in the male patients after BMT. In conclusion, the rapid impairment of bone formation and the increase in bone resorption, as shown by the biochemical markers in this study, might play a role in post-BMT bone loss.