GROWTH-HORMONE THERAPY IN PRE-PUBERTAL CHILDREN WITH NOONAN-SYNDROME - FIRST YEAR GROWTH-RESPONSE AND COMPARISON WITH TURNER-SYNDROME

We studied the growth-promoting effect of treatment with recombinant h uman growth hormone in 23 prepubertal children with Noonan syndrome, a ged between 5.4 and 14.3 y, and all with a height < 1.4 SD for Tanner standards. The growth response and skeletal maturation after ly of rec ombinant human growth hormone treatment (0.15 U/kg/day given by daily injection) in the Noonan syndrome patients was compared with the auxol ogical changes observed in a group of 17 girls with Turner syndrome wi th a comparable age and height deficit who were treated with recombina nt human growth hormone in a similar way. During 1 y of treatment, the mean +/- SD height velocity increased by 4.0 +/- 1.6 cm/y in the Noon an syndrome group and by 3.6 +/- 1.3 cm/y in the Turner syndrome group . Height SDS for chronological age in the Noonan syndrome group increa sed by 0.53 +/- 0.46 (p < 0.001). In the Noonan syndrome patients the changes in height velocity were positively related to birthweight (r = 0.48, p < 0.05). The changes in height velocity or height SDS were no t related to the age, height deficit or a delay in bone age maturation at start of treatment. In neither the patients with Noonan syndrome n or Turner syndrome was an acceleration of bone maturation found. We co nclude that treatment with recombinant human growth hormone in pre-pub ertal NS patients induces an increase in height velocity and height SD S comparable to that observed in Turner syndrome girls.