Quantitative ultrasound detects bone changes following bone marrow transplantation in pediatric subjects with hematological diseases: a longitudinal study.

BACKGROUND

Bone marrow transplantation (BMT) is associated with bone morbidity. We investigated bone status with quantitative ultrasound (QUS) in pediatric patients with hematological diseases prior to and up to 3 yr following BMT.

METHODS

Phalangeal QUS measures for amplitude- dependent speed of sound (Ad-SoS) and bone transmission time (BTT) were obtained in 40 hematological patients (25 with malignant, 15 with non-malignant disease; 9.7+/-4.9 yr) before BMT and 6, 12, 24, and 36 months after BMT. Bone parameters were expressed as Z-scores based on age-sex-matched normal controls.

RESULTS

Mean Ad-SoS and BTT Z-scores were normal before BMT and reduced at 36 months (analysis of variance: p=0.0542 and p=0.0233). Ad-SoS and BTT Z-scores remained relatively stable in the first 6 months after BMT and then progressively decreased reaching a plateau at 12-36 months. In non-malignant patients, BTT Z-score decreased at 6-12 months (p=0.029) and subsequently increased, while in malignant patients BTT Z-score showed a decrease at 12-24 months. Pre-pubertal subjects displayed a drop of BTT Z-Score values at both 12 (p=0.023) and 36 months after BMT (p=0.049), while BTT Z-score remained relatively unchanged in pubertal subjects. Early impairment of BTT Z-score was found in patients who suffered acute graft versus host disease (GVHD) compared to patients without this clinical condition; BTT Z-score was lower at 36 months (p=0.045).

CONCLUSIONS

Longitudinal assessment by QUS of pediatric BMT survivors evidenced that bone status is mildly affected up to 36 months after BMT, mainly in malignant patients, in pre-pubertal subjects at BMT and in patients who suffered acute GVHD.