Abstract
In view of the high observed frequency of bone events following allogeneic haematopoietic stem cell transplantation (allo-SCT), the aim of this prospective study was to evaluate pre-transplant bone status in allo-SCT patients. In the month before transplantation, bone-loss risk factors were documented for 27 patients. We measured the levels of bone remodelling markers (BRMs: plasma osteocalcin and bone & total alkaline phosphatases for bone formation; CTX and telopeptides for bone resorption), together with plasma creatinine, intact PTH, TSH, testosterone, LH, FSH, 25 OH vitamin D, serum calcium & phosphorus and calciuria. In addition, bone mineral density (BMD) at the lumbar spine, femoral neck and hips was measured using double-energy X-ray absorptiometry (DEXA). Spine X-ray measurements were also made. Bisphosphonate, oral calcium and vitamin D or testosterone were administered according to the results of the evaluation.Between June 2006 and March 2007, 13 males and 14 females underwent allo-CST for haematological malignancies. The median age at transplantation was 44 years (range: 22–60). Eighteen had received prior corticosteroid therapy, 10 were smokers and 2 had a history of alcohol abuse. All had received prior chemotherapy, including 2 patients having already undergone autologous SCT. Ten of the 14 women were post-menopausal but none was on hormone replacement therapy. The median BMI was 24 kg/m2 (19–35). The daily calcium intake was low, with a median value of 950 mg/day (467–1852). While serum calcium, phosphorus and creatinine levels were within the corresponding normal ranges for all patients, 15 individuals displayed vitamin D deficiency and 6 had calciuria < 100 mg/day. Two patients suffered from hyperparathyroidism. In terms of BRMs, the patients respectively displayed a normal profile (n=9), high bone resorption activity (n=12) or high bone formation/resorption activity (n=5). One patient had hyperthyroidism and another presented hypotestosteronaemia. Bone density results were normal in 16 patients and abnormal in 11 (41%), including 8 with osteopaenia and 3 with osteoporosis. Vertebral fractures were observed in 4 patients. Overall, 18 patients (67%) were considered as having a pathological bone status and required treatment with bisphosphonate alone (n=5), vitamin D supplementation alone (n=11) or both (n=2).This study revealed that a large proportion of allo-CST patients have pre-existing abnormal bone status and thus demonstrates the importance of pre-transplant bone status evaluation in allo-CST candidates. The implementation of appropriate bone-related treatments may reduce the frequency of post-transplant bone events.
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