Replacement of growth hormone (GH) in normally growing GH-deficient patients operated for craniopharyngioma.

Abstract

Removal of a craniopharyngioma usually results in panhypopituitarism. Some children, however, grow normally or even excessively after extirpation of the tumor despite a proven lack of GH and have so far not been treated with hGH. We studied the effects of short (2-day) and long term (1-yr) administration of hGH on metabolism and growth in six patients receiving regular hormonal replacement therapy. During short term human (h) GH treatment, 15N retention was not significantly increased (mean +/- SEM, 115.4 +/- 9.6% of basal balance) and was not different from the control value. In contrast, 15N retention was 210.3 +/- 20.7% in children with GH deficiency from other causes. Long term administration of hGH (2 IU/m2.day, sc, for 12 months) did not influence growth velocity, but increased the calf circumference and decreased the body mass index and skinfold thickness in prepubertal patients. Insulin-like growth factor-I (IGF-I), IGF-binding protein-3 (IGFBP-3), and the 150-kilodalton IGFBP complex were decreased before and restored to normal during treatment. The reverse was observed for the 50-kilodalton IGFBP complex. Growth (velocity) in these patients did not correlate with any of the usual indicators of the growth status and remains unexplained. Although hGH did not affect growth, it had other beneficial effects and is recommended for these patients.