Growth, growth hormone and final height after BMT. Possible recovery of irradiation-induced growth hormone insufficiency.

The aim of the present study was to assess growth, final height, growth hormone (GH) secretion and growth factors after BMT including TBI in childhood. The median age of the 25 participants was 11.3 years at BMT, and a median of 7.5 years had elapsed since BMT. The median height standard deviation score (SDS) declined significantly from diagnosis until 4 years after BMT (n = 25, P = 0.015), and decreased 1.08 SDS from diagnosis until final height (n = 14, P = 0.030). Sitting height to standing height ratio was impaired, -0.64 SDS, P < 0.05. GH insufficiency was found in 32% at follow-up. Repeated assessments of GH production over the years indicated improvement in GH secretion in nine individuals. Evaluation of spontaneous 24-h GH secretion indicated a secretory pattern similar to controls, although the total amount of GH secreted was lower. Neither insulin-like growth factor-1 (IGF-1) nor IGF binding protein-3 (IGFBP-3) alone could be used as a marker of GH insufficiency. IGF-1 was low: -1.18 SDS; (P < 0.001). In conclusion, our study demonstrated the impact on growth, final height, body proportions, GH secretion and growth factors after BMT including TBI. We hypothesize that children who receive BMT at a younger age are more at risk of loss of final height and abnormal body proportions. Our data indicate that some improvement in GH production may occur over the years.