Short-term therapy with recombinant growth hormone in polytransfused thalassaemia major patients with growth deficiency.

Growth failure is commonly described in polytransfused thalassaemia major patients (Th) with or without growth hormone (GH) releasing hormone-GH axis impairment. We have investigated the efficacy of short-term recombinant GH (rhGH) therapy (Saizen [Serono] 0.1 IU/kg/day 6 evenings/week administered s.c. for 12 months) on growth and predicted final height in 28 (19M, 9F) regularly transfused Th with growth deficiency (aged 14.8 +/- 2.0 yr) on long term desferrioxamine s.c. therapy. All Th had no evidence of congestive heart failure, hypothyroidism or impaired glucose tolerance; in all patients the GH peak (evaluated during both insulin and clonidine test) was < or = 20 mIU/l; hypergonadotropic hypogonadism was excluded in Th with delayed puberty. At the start of therapy height age (HA)/bone age (BA) ratio was 0.92 +/- 0.12. Bone age delay was positively correlated to chronological age (CA), serum ferritin levels (mean of the last three years), the age at the start of chelation therapy, growth velocity calculated for CA during the last year; a positive correlation was also found between circulating IGF-I levels and age at the start of chelation therapy. After 1 year on rhGH therapy there was a significant increase of height calculated for CA (not for BA), of growth velocity calculated for both CA and BA and of circulating IGF-I levels; the HA variation/BA variation ratio was 1.85 +/- 1.71, without any significant difference between predicted final height at the start (-1.08 +/- 1.28 SDS) and at the end of rhGH therapy (-0.88 +/- 1.13). The variation of height calculated for CA was positively correlated to both CA and growth velocity during the last year before rhGH therapy (calculated for CA) and negatively to the height at the start (calculated for CA). There were no side effects and haematological parameters did not show significant changes. In conclusion, our data, obtained in a relatively large group of Th, confirm the emerging results of short-term (12 months) rhGH therapy on growth, as shown by the increase of both growth velocity and height calculated for CA. With regard to final height, although the mean variation of HA/variation of BA ratio was 1.85, no significant increase of the predicted final height was found between the start and the end of rhGH therapy. We are evaluating the effect of long-term rhGH therapy on growth in these patients.