Synthetic, amidated, 44 amino acid GH-releasing hormone ( GRH -44) was administered iv at a dose of 5 micrograms/kg to 20 patients with severe GH deficiency (GHD), 6 children and adolescents with partial GHD, and 6 non-GH deficient ( NGHD ) children and adolescents. The 17 patients with severe GHD that responded to GRH -44 had lower peak concentrations of plasma GH than the NGHD individuals (5.0 +/- 1.2 (SEM) vs. 27.2 +/- 3.5 ng/ml; P less than 0.0001). The children and adolescents with severe GHD tended to have higher peak GH responses to GRH -44 than the GHD adults (6.9 +/- 1.7 vs. 2.4 +/- 0.3 ng/ml) although the difference was not significant. The peak GH concentration was attained earlier in the GHD children and adolescents than in the GHD adults (28 +/- 4.7 vs. 69.3 +/- 13 min, P less than 0.004). There was a negative correlation between chronological age and peak plasma GH response to GRH in the children and adolescents with severe GHD (r = -0.758, P less than 0.02). Children and adolescents with partial GHD had a higher mean peak concentration of plasma GH (13. 1 +/- 1.8 ng/ml) than the children, adolescents, and adults with severe GHD (P less than 0.04), but one lower than the NGHD children and adolescents (P less than 0.05). In both severe and partial GHD the GH response to GRH was greater than that elicited by standard pharmacological tests. Serum somatomedin-C did not increase after a single pulse of GRH -44 in the 12 GHD patients studied. PRL increased minimally 30 min after 5 micrograms/kg iv GRH -44 in patients with multiple hypothalamic-pituitary hormone deficiencies but not in patients with isolated GHD or in NGHD individuals. The GH responses to GRH suggest that the majority of patients with isolated GHD as well as those with multiple hypothalamic-pituitary hormone deficiencies have deficiency of hypothalamic GRH . Lack of a GH response to a single pulse of GRH does not exclude GRH deficiency as priming of the somatotrope with multiple pulses of GRH may be necessary to rule out a hypothalamic defect in the nonresponders. The results of this study support the potential usefulness of GRH or its analogs in the diagnosis and treatment of selected patients with disorders of GH secretion.

Significant growth retardation was found in 115 survivors of childhood acute lymphoblastic leukemia (ALL) who had completed their growth. These children were diagnosed before 12 years of age and treated on four protocols in a single institution; all received either cranial (n = 78) or craniospinal (n = 37) prophylactic irradiation. Patients' heights at diagnosis were within expected ranges, but final heights were greater than or equal to 1 SD below population means in 74% of cases and greater than or equal to 2 SD in 37%. Effects on growth were more pronounced for children who had received craniospinal irradiation, but decrements were also significant in the cranial irradiation group, with adult heights greater than or equal to 2 SD below population norms in 32%. Growth retardation was significantly greater (P less than .0001) in children who had earlier disease onset. Growth deceleration occurred not only during chemotherapy but during a later period that followed an interval of improved growth in many cases. Thus, late decrements in growth may be missed in studies that do not follow patients until they have attained final heights. These findings indicate that abnormally short stature among survivors of ALL merits further clinical and research attention.

This study suggests that GH replacement therapy is safe and efficacious for the correction of GH deficiency in survivors of childhood ALL.

Risk factors were identified for abnormally short stature, which was defined to be a decrease of 1.5 SDS in height from diagnosis to age 18 years. These factors include younger age and above-average height for age at diagnosis (height SDS greater than 0), craniospinal irradiation, and greater decrease in height SDS during antileukemic therapy. Risk factors for obesity at age 18 years include weight SDS greater than 0 and greater than height SDS at 1 year after the end of chemotherapy.