Effect of human recombinant growth hormone therapy on circulating levels of erythropoietin and granulocyte-colony stimulating factor in short children.

Several reports suggest a role of growth hormone (GH) in the regulation of the haematopoietic system, as regards the normal differentiation and function of blood cells. The aim of this study was to evaluate the influence of rhGH therapy on erythropoietin (Epo) and granulocyte-colony stimulating factor (G-CSF) levels in 18 prepubertal short children with idiopathic GH deficiency (GHD) (n = 8) or without GHD (n = 10), during the first year of treatment. In non-GHD children Epo levels significantly decreased and G-CSF levels increased from basal to 12 months of therapy, whereas in GHD children they did not change significantly. Circulating levels of G-CSF are significantly lower in GHD than in non-GHD children. In non-GHD children the number of red blood cells, haemoglobin and haematocrit values significantly increased after 1 year of rhGH treatment. rhGH therapy influences Epo and G-CSF levels in short non-GHD children, while it shows no effects in GHD children.