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Objective: Birth weight influences both postnatal growth and the initial response to GH therapy in GH-deficient subjects, but its relationship to final height is uncertain. Therefore, we examined final height results in a group of subjects treated for GH deficiency who were born small, appropriate or large for gestational age (GA)., Design: Retrospective study., Patients: 108 GH-treated patients (age at diagnosis 11.1 +/- 2.0 years) affected by idiopathic and isolated GH deficiency (peak < 8 microg/l after pharmacological and/or nocturnal mean GH concentration

Aims: To evaluate the developmental pattern of fetal growth hormone (GH), insulin-like growth factor I (IGF-I), GH binding protein (GHBP) and IGF binding protein-3 (IGF-3); to determine the implications for fetal growth., Methods: Serum GH, IGF-I, GHBP and IGFBP-3 were measured in 53 fetuses, 41 aged 20-26 weeks (group A) and 12 aged 31-38 weeks (group B). Fetal blood samples were obtained by direct puncture of the umbilical vein in utero. Fetal blood samples were taken to rule out beta thalassaemia, chromosome alterations, mother to fetus transmissible infections, and for maternal rhesus factor. GHBP was determined by gel filtration chromatography of serum incubated overnight with 125I-GH. GH, IGF-I and IGFBP-3 were determined by radioimmunoassay., Results: Fetal serum GH concentrations in group A (median 29 micrograms/l, range 11-92) were significantly higher (P < 0.01) than those of group B (median 16.7 micrograms/l, range 4.5-29). IGF-I in group A (median 20 micrograms/l, range 4.1-53.3) was significantly lower (P < 0.01) than in group B (median 75.2 micrograms/l, range 27.8-122.3). Similarly, IGFBP-3 concentrations in group A (median 950 micrograms/l, range 580-1260) were significantly lower than those of group B (median 1920 micrograms/l, range 1070-1770). There was no significant difference between GHBP values in group A (median 8.6%, range 6.6-12.6) and group B (median 8.3%, range 6-14.3). Gestational age correlated positively with IGF-I concentrations (P < 0.0001) and IGFBP-3 (P < 0.0001) and negatively with GH (P < 0.0001). GHBP values did not correlate with gestational age. Multiple regression analysis showed a negative correlation between GH:IGF-I ratio and fetal growth indices, Conclusions: The simultaneous evaluation of fetal GH, IGF-I, IGFBP-3 and GHBP suggests that the GH-IGF-I axis might already be functional in utero. The progressive improvement in the efficiency of this axis in the last part of gestation does not seem to be due to an increase in GH receptors.

Urinary growth hormone was measured in 54 children with short stature who had growth hormone deficiency that was initially diagnosed pharmacologically (arginine and L-dopa) and physiologically (mean growth hormone concentration during sleep evaluated twice). Based on the growth hormone response to pharmacological tests the subjects were subdivided into three groups: group A, 20 subjects with normal response (peak concentration > 8 micrograms/l); group B, 20 subjects with response between 4 and 8 micrograms/l; and group C, 14 subjects with response < 4 micrograms/l. In group A four subjects had an abnormally low nocturnal mean growth hormone concentration (< or = 3.3 micrograms/l). In group C seven subjects had multiple pituitary hormone deficiency and abnormal magnetic resonance imaging. All subjects had urine collected from 8.00 pm to 8.00 am for 4-5 consecutive nights. A positive correlation was found between serum nocturnal mean growth hormone values and urinary growth hormone in all subjects. Mean (SD) concentrations of urinary growth hormone were similar in groups A (18.0 (9.5) ng/g creatinine) and B (13.6 (5.9) ng/g creatinine), but significantly higher than that of group C (3.4 (3.7) ng/g creatinine). Considering as abnormal urinary growth hormones below the lower limit of the range in group A, specificity and sensitivity of urinary growth hormone was 100% and 35% respectively. Sensitivity for groups B and C were 5% and 78% respectively. When considering only the subjects of group C with pathological magnetic resonance findings, sensitivity increased to 100%. In the four subjects of group A with mean growth hormone concentration < or = 3.3 micrograms/l, specificity decreased to 80%. It is concluded that urinary growth hormone assay is characterised by a sensitivity too low to be regarded as improving the traditional diagnostic approach to define growth hormone deficiency, unless it is used to identify subjects with the most severe deficiencies.

The aim of the study was to evaluate the immunogenicity of different commercial recombinant-growth hormone preparations. The presence of antibodies to growth hormone was tested in 210 growth hormone-deficient children at 6-month intervals during treatment for 6-66 months. The patients were treated with three preparations (groups A, B and C of 70 cases each) having the authentic growth hormone sequence. Groups A and B received hormone synthesized by the recombinant DNA technique in E. coli, while the group C preparation was produced in a mammalian cell line. The preparations showed poor immunogenicity and antibodies were found as follows: 1.4% in patients of group A (1 case: binding capacity 0.2 mg/l and Ka 3.5 10(7) l M-1), 2.8% in patients of group B (2 cases; case 1 binding capacity 0.7 mg/l and Ka 1.5 10(7) l M-1; case 2 binding capacity 0.04 mg/l and Ka of 1.8 10(8) and 6.5 10(6) l M-1), and 8.5% in group C (6 cases; binding capacity from 0.4 to less than 0.02 mg/l, Ka from 1.6 10(7) to 3.8 10(8) l M-1). Only two patients of group C presented the antibodies in two subsequent examinations; in the other patients the positivity was found once. In all patients positive samples were found at intervals of 6-24 months after the start of therapy. In all antibody-positive patients growth velocity presented no decrease at the time of antibody detection and was never different to that of negative patients. We conclude that the three commercial preparations examined showed poor immunogenicity without clinical relevance.

Objective: To determine long-term growth response to growth hormone (GH) therapy in patients with isolated GH deficiency who had been small for gestational age and in those who had been appropriate in size for gestational age., Design: Longitudinal, case-control study., Setting: Pediatric clinic, endocrinology center, University of Bologna, Italy., Patients: Sixteen GH-deficient children, small for gestational age with unknown cause, and 16 GH-deficient children, appropriate in size for gestational age, who were matched for chronologic age, bone age, pubertal stage, and target height at the beginning of treatment and were treated for 36 months., Intervention: Recombinant human GH given subcutaneously at a dose of 20 IU/m2 per week in six doses per week for 36 months., Measurements: Growth hormone levels (fluoroimmunoenzymatic method), levels of insulin-like growth factor I (radioimmunoassay), and complete 36-months auxologic follow-up., Results: Patients who were small for gestational age had a modest improvement in height for chronologic age but no increase in predicted final height. Patients who were appropriate in size for gestational age had significantly better improvement in both measurements (multivariate analysis of variance: F = 6.3 (p < 0.001) and F = 3.8 (p < 0.05), respectively). Catch-up growth was similar during the first year of therapy for the two groups, after which the linear growth velocity decreased more rapidly in the small-for-gestational-age patients (multivariate analysis of variance: F = 4.9 (p < 0.05))., Conclusions: The constitutional component of the statural deficiency of small-for-gestational-age children seemed to prevail over hormonal deficiency during treatment with GH. Further follow-up to final height is necessary to evaluate these different responses.

There is currently a debate about the use of pharmacological and physiological tests to define GH deficiency and predict response to GH therapy. In addition, a good response to therapy has also been described in subjects without GH deficiency. For further information, we reevaluated GH secretion during replacement therapy in a group of children defined as GH deficient and examined response to therapy in the subjects subdivided according to secretion. One hundred eighty four children (113 boys and 71 girls) initially diagnosed with GH deficiency by means of pharmacological (peak < 8 micrograms/L after arginine and L-dopa tests) and physiological tests (mean nocturnal concentration < or = 3.3 micrograms/L during sleep test) underwent the same tests 2.8 +/- 1.1 yr after start of GH therapy. Sixty eight patients were retested 1.5 +/- 0.4 yr after first retesting. At diagnosis 122 subjects had pathological pharmacological and physiological tests (group A), 30 subjects normal sleep test with pathological pharmacological tests (group B), and 32 subjects pathological sleep test with normal pharmacological tests (group C). At diagnosis 140 subjects were prepubertal and 44 pubertal. To evaluate response to therapy in relation to GH secretion at diagnosis and at both retestings, a number of auxological parameters were calculated during treatment. At first retesting, 107 subjects (58.1%) changed initial group of diagnosis, 34 of whom (18.5%) presented normal secretion in both pharmacological and physiological tests (group D). At second retesting, 31 of the 68 subjects reexamined (45.6%) changed first test results, and 33 (48.5%) reverted to the initial group of diagnosis; none of the 6 subjects of group D maintained normal secretion. Although the percentage of normalized subjects was higher in pubertal subjects (36.4%; P = 0.0003) than prepubertal subjects (8.9%), puberty did not prevent a reduction of secretion in some subjects. Response treatment during the first year of therapy was similar in the various groups. GH secretion seems to change in both prepubertal and pubertal children diagnosed with GH deficiency when pharmacological and physiological tests are repeated over time. Moreover, such tests may not represent a reliable tool for predicting response to treatment. GH secretion normalization at retesting may not necessarily represent the end of a transient secretory defect.

The growth hormone (GH) gene (hGH-N) cluster was analysed using polymerase chain reaction, Southern and polymorphism analysis in five patients (including two pairs of siblings) with extreme short stature and absence of GH secretion. Patients 1 and 2 (siblings) were homozygous for a large deletion removing four genes of the cluster: hGH-N, hCS-L, hCS-A and hGH-V. Both siblings produced high anti-GH antibody levels in response to exogenous GH therapy, followed by growth arrest a few months after starting replacement therapy. In patient 3 we detected a heterozygous deletion which involved three genes of the cluster (hCS-A, hGH-V, hCS-B) and left an intact hGH-N gene. Direct sequencing of hGH-N specific amplified fragments excluded the presence of any point mutations in exons and splicing regions. In patients 4 and 5 (sisters) our study did not demonstrate any gene deletions. Analysis of polymorphic restriction patterns in this family demonstrated that both sisters inherited the same alleles from the father but different alleles from the mother, suggesting that the defect was not linked to the hGH-N gene. These results confirm the difficulty of clinical identification of subjects with hGH-N deletion and underline the importance of DNA analysis in patients with absence of GH secretion and extreme growth retardation.

11 patients with 21-hydroxylase deficiency were treated with three different corticosteroids and two different distributions of therapy during daytime. We found that: 1) a higher dose of steroid in the evening had a markedly inhibitory effect on nocturnal GH secretion; 2) of the steroids we used, dexamethasone caused the greatest reduction in nocturnal GH secretion; 3) in this study adrenal hormones seem less influenced by the different distribution of the corticosteroids during the 24 hours period.

Objective: To determine the effects of 18-Gy cranial irradiation on growth, growth hormone (GH) secretion, and pituitary magnetic resonance imaging in children who underwent previous irradiation for treatment of acute lymphoblastic leukemia., Design: Clinical survey., Setting: Department of Pediatrics of the University of Bologna (Italy)., Patients: Ten boys and 18 girls who were treated for acute lymphoblastic leukemia; median age at diagnosis was 3.1 years and at the end of follow-up was 11.5 years., Measurements and Results: Height was periodically measured from diagnosis until the end of follow-up, when GH secretion study and magnetic resonance imaging were performed. The mean height SD score was significantly lower than at diagnosis only at the end of treatment. Nocturnal mean GH concentration and GH response to pharmacological tests (arginine and levodopa [L-dopa]) were pathological in 22 cases (81.5%) and 18 cases (64.3%), respectively. Sixteen cases (59.2%) had a blunted GH release to the three tests. Mean pituitary anterior lobe height was reduced and seven subjects (25%) showed an empty sella., Conclusions: Cranial irradiation with 18 Gy does not seem to influence the growth pattern of most children who are treated for acute lymphoblastic leukemia, despite severe impairment of GH secretion and morphological abnormalities of the sellar area. However, a follow-up until final height is necessary.

We examined the effect of growth hormone (GH) therapy on thyroid function in 57 children with isolated GH deficiency and whether this effect could influence their growth response. Thyroid function and insulin-like growth factor I levels were measured before and after 3, 6, and 12 months of recombinant-GH therapy (20 U/m2 per week, given subcutaneously), after a 1-month withdrawal from therapy, and after a further 6 months of GH administration. The serum concentration of triiodothyronine (T3) and the T3/T4 (thyroxine) ratio increased after 12 months of GH treatment, whereas total T4 and free T4 levels decreased; thyrotropin levels did not change significantly during treatment but increased after a 1-month withdrawal. After a further 6 months of GH therapy, an increase in T3 levels and in the T3/T4 ratio and a decrease in total T4 and free T4 levels were found again, and thyrotropin levels decreased. The increment in growth velocity after 12 months of therapy correlated positively with the T3/T4 ratio and negatively with total T4 and free T4 values. These data confirm in children a GH-induced enhancement of peripheral conversion of T4 to T3. This effect appears to be more evident in children who are most sensitive to GH in terms of growth-promoting activity.

Possible causes of error in the diagnosis of isolated GH deficiency are the variability of GH response to repeated tests, the existence of transient GH deficiencies, and the low GH levels found in short statured children with delayed puberty. Sixty-three patients with variously expressed GH deficiency were retested (1 sleep test and 2 pharmacological tests) after 1-3.9 yr of GH therapy (dose, 15 U/m2.week). Forty-eight subjects had arginine, L-dopa, and sleep tests (mean serum GH concentration) twice, while 15 had only arginine and L-dopa tests. All patients were retested 1 month after withdrawal from therapy. The criteria used to subdivide the patients were pubertal development and response to pharmacological and sleep tests at first diagnosis and on retesting. The initial diagnosis in 33 subjects (52.4%) was not confirmed, and 13 (20.6%) were no longer deficient on retesting. The percentage of normalization was high for the sleep test (43.9%), lower for the pharmacological test (24.5%), and lower still (12.9%) for pharmacological and sleep tests considered together. While none of the 28 subjects who remained prepubertal at retesting normalized in any of the tests, 13 of the 35 subjects retested during puberty did. When normalization was observed in pubertal subjects, it occurred predominantly in the sleep test. Growth velocity and height age/bone age increment ratio after the first year of therapy were no different for the groups of subjects classified according to GH secretion on retesting. Our study demonstrates that a number of children diagnosed as GH deficient do not have a true deficiency. However, such a diagnostic error seems to have little effect, at least in the first year of therapy, on the effectiveness of GH treatment.

In five clinical studies performed in Austria, France, the FRG, Italy, Switzerland, the UK and the USA, 304 growth hormone (GH)-deficient children were treated with recombinant human GH (rhGH) of mammalian cell origin. Two hundred and twenty-five patients were previously untreated (naive patients), and 79 were transferred from pituitary hGH after interruption of therapy for at least 6 months (transfer patients). Two treatment protocols, differing in both dose and frequency of injections, were used: (1) a dose of 0.6 IU/kg body weight per week was administered in 3 s.c. injections to 203 patients (178 naive, 25 transfer; group 1); and (2) a dose of 0.45 IU/kg body weight per week was administered in 7 s.c. injections to 101 patients (47 naive, 54 transfer; group 2). After 1 and 2 years of treatment, 143 and 109 naive, and 51 and 46 transfer patients, respectively, were still prepubertal, and their data were analyzed for efficacy. During the 1st year of treatment, both naive and transfer patients on daily injections (group 2) demonstrated better growth than those on 3 injections per week (group 1), with height velocities (HVs) of 10.6 +/- 2.7 cm/year (group 2) versus 8.6 +/- 2.0 cm/year (group 1) for naive patients (p < 0.001), and 9.9 +/- 1.9 cm/year (group 2) versus 7.2 +/- 2.7 cm/year (group 1) for transfer patients (p < 0.001). The corresponding changes in height standard deviation score (delta H SDS) for chronological age (CA) were +1.3 +/- 0.6 (group 2) versus +0.8 +/- 0.5 (group 1) for naive patients (p < 0.01), and +1.1 +/- 0.3 (group 2) versus +0.6 +/- 0.4 (group 1) for transfer patients (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Serum growth hormone (GH), insulin-like growth factor (IGF-I), insulin and C-peptide were measured by RIA in fetal blood collected in utero by umbilical cord puncture performed for a variety of indications. Eighty-four fetuses were aged 19-25 weeks and 14 were 26-37 weeks. IGF-I values were lower than the sensitivity of the method. The range for GH was 3-197 micrograms/l (GH-micrograms/l x 2 = mU/l), for insulin 14.3-117 pmol/l, for C-peptide 66.2-827.5 pmol/l. GH significantly increased from week 19 to 25; insulin and C-peptide levels increased from week 19 to 37. GH levels at 19-25 weeks were significantly higher in fetuses with femoral length less than the 5th compared with those with femoral length greater than the 95th centile for that age. GH and insulin levels did not correlate with weight at birth or with maternal hormone levels. These data provide evidence for a presence in living fetuses, from the 19th week, of high levels of GH and of insulin levels not very different from those in adults but these hormones do not seem to be directly responsible for fetal growth.

Forty-nine children with short stature (age range, 4.1-15.9 yr) were examined. Twenty-four (group 1) were submitted twice to an arginine and a sleep test (12-h overnight GH profile). Twenty-five patients (group 2) were submitted twice to an arginine and L-dopa test. Coefficients of variation were calculated between both the results of pharmacological (peak and area under the curve) and sleep tests [mean GH concentration (MGHC), peak, area under the curve, number of peaks above 5 micrograms/L, and peak area]. In group 1 the coefficient of variation of sleep test parameters was significantly lower than that of pharmacological tests (P less than 0.01 to less than 0.001). In the sleep test the area under the curve and MGHC were the most constant parameters. Group 2 showed no difference between the coefficients of variation of the two pharmacological tests. Considering groups 1 and 2 together, the coefficients of variation of the sleep test, in particular the MGHC and area under the curve, were lower than those of the two pharmacological tests. Eight of 24 subjects in group 1 showed a low GH level in 1 series of tests, and a normal level in the other series. Five of 18 subjects in group 2 showed an abnormally low GH response to the arginine and L-dopa tests and a normal response to the 2 repeated tests. Therefore, to prevent an erroneous interpretation of the GH test results, it is very important to perform a sleep test and repeat it whenever GH secretion seems to be deficient or at the lower limits of normalcy.

Urinary albumin excretion (UAE) was determined by radioimmunoassay in two 24 h urine collections from 125 diabetic children and adolescents and from 71 normal children matched for age and sex. Thirteen patients (10.4%) aged greater than 12 years had microalbuminuria, i.e. log transformed UAE levels above the upper normal range (24.5 mg/24 h). UAE values were positively correlated with age, GH secretion, but not with duration of disease, glycosylated hemoglobin, renal size or N-acetyl-beta-glucosaminidase excretion. Diabetic normoalbuminuric children aged 10 years and older had significantly higher UAE than controls and than younger diabetic patients matched for duration of disease. HLA DR3/DR4 heterozygosity frequency was significantly higher (p less than 0.01) in the microalbuminuric group than in the normoalbuminuric. All microalbuminuric subjects (n = 8) with short duration of disease (3.92 +/- 3.43 yr) developed diabetes at puberty. In conclusion, our cross-sectional study suggests: if a number of factors are combined, i.e. HLA DR3/DR4 heterozygosity, onset of disease at puberty and higher GH values, the probability of developing abnormal levels of UAE will increase.

Twenty-five GH-deficient children were treated with GHRH (1-44), once daily sc for 6-24 months. At the 6th month of therapy, 40% of our patients showed a catch-up growth (responders), while the remaining 60% did not (nonresponders). No differences in auxological and biological variables at inclusion were found between the two groups. However, integrated GH secretion elicited by iv GHRH at inclusion was significantly (p less than 0.025) higher in responders than in non responders. During GHRH therapy, no significant increase in IGF 1/SmC was found in both groups. In all patients treatment was discontinued after 6-24 months, when its effect on growth rate failed. After a wash-out period of at least 6 months, patients were submitted to biosynthetic GH therapy. After 6 months of GH treatment a significant catch-up growth was found in both responder and non-responder children. Although the majority of GH-deficient children have hypothalamic rather than pituitary dysfunction, GHRH therapy is found to be less effective than GH treatment. Other methods of GHRH administration are worth investigating.

The thymus produces humoral factors that induce the proliferation and differentiation of T cells which are responsible for cell-mediated immunity. Experimental data have suggested that this thymic hormone production is modulated by the neuroendocrine network and, in particular, by growth hormone (GH) and thyroid hormones. To study the role played by GH in thymic endocrine activity in humans, the circulating level of one of the best known thymic peptides, i.e. thymulin (Zn-FTS), has been determined, after a washout period of 2 weeks without GH treatment, in GH-deficient children before and after a single injection of GH. The basal thymulin level is consistently lower in GH-deficient children than in healthy age-matched controls. A single injection of GH induces a significant increment of the thymulin level for at least 48 h. Since thymulin activity may also depend on zinc bioavailability, on thyroid hormone turnover and on the eventual presence of thymulin-inhibitory substances, all these aspects have been checked. No supporting evidence regarding the existence of these kinds of interferences in GH-deficient children has been substantiated. A positive correlation has been found between the serum level of insulin-like growth factor I, but not of GH, and thymulin activity. These data suggest that GH may directly or indirectly modulate the thymic endocrine function in humans. Whether and to what extent such a modulation is relevant to the functioning of the immune system remains to be ascertained.

IGF-I, testosterone and estradiol levels were evaluated in 8 girls with androgen insensitivity immediately before and from 1 to 3 months after bilateral gonadectomy. In 6 patients GH secretion was evaluated before and after gonadectomy by means of an arginine test and in 3 a sleep test was also performed. Mean IGF-I level before surgery was significantly higher than that of normal controls (2850 +/- 1230 vs 1680 +/- 1040 U/l, p less than 0.025). After gonadectomy a significant decrease was evident for testosterone, estradiol and IGF-I levels. A positive correlation between IGF-I and estradiol levels was present before surgery (p less than 0.005). The presence of a correlation with estradiol, but not with testosterone, and the knowledge that this syndrome is due to an insensitivity to androgens, but not to estradiol, support the hypothesis that the estradiol level is the major determinant for the control of IGF-I values in these patients. After gonadectomy, a substantial decrease of the 12-h nocturnal GH secretion was evident. Comparison of the nocturnal GH levels before surgery of the 3 patients with those of normal subjects of the same age showed hormonal values higher than 1 SD over the mean values of control subjects. Even if the number of patients studied is too small to draw any definitive conclusion, these data may suggest that sex hormones play a role in the control of IGF-I levels, a function which seems to be mediated through GH secretion.

We used the radioimmunoassay (RIA) method to determine somatomedin-C (SmC) basal values in 59 diabetic children and adolescents (20 prepubertal and 39 pubertal subjects; age range 2.75-20.16 yr; duration of diabetes 0.08-15.83 yr) and in 274 control subjects. In comparing diabetic subjects with controls, we considered only those 50 diabetic subjects who were age matched with the controls, i.e., those not over 16 yr chronological age. SmC basal levels in pubertal diabetic patients were no different from those of pubertal age-matched control children, whereas in prepubertal diabetic patients SmC was significantly lower than in the respective control children (P less than .001). No correlation was found between the z score for SmC (i.e., the number of standard deviations each SmC level is from the age- and sex-normalized mean) and duration of disease, velocity standard deviation score, severity of fluoroangiographic retinal changes, basal C-peptide values and HbA1 levels. No differences were encountered in mean SmC and SmC z-score values in the separate groups of poorly, fairly, and well-controlled diabetic children, in the groups with and without residual pancreatic activity, and in the group with and without retinal changes. In 16 of the pubertal diabetics and in 15 pubertal controls, serum glucose, growth hormone (GH), and SmC concentrations were determined during the night. The integrated nocturnal secretion of SmC was no different in diabetics than in controls, whereas the integrated nocturnal secretion of GH was significantly (P less than .025) higher in diabetics than in controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Twenty-four euthyroid children with idiopathic pituitary dwarfism were studied. The euthyroid state for seven of these patients was determined by negative physical examinations, normal plasma T4 assays and normal 131I uptakes. For the other children, thyroid function was evaluated with T3 and T4 assays and on the basis of the TRH test. Each of the children was treated with HGH in one of three different ways. The first group (five cases) was given a HGH dose, ranging from 12.4 to 17.2 IU/m2//week. The second and third groups (nine and ten cases, respectively) were treated with 10 and 20 IU/m2/week, respectively. Treatment was carried out for periods ranging from 6 months to 6 years. After no less than 6 months of treatment, and at intervals of 6 months (or some multiple of 6 months) plasma T3 and T4 assays, as well as a TRH test were performed in each patient. In some patients one of the indices was once beyond the upper or lower limit of the normal range (none of the children presented simultaneous abnormal levels of more than one index during the controls). This value, however, returned to within normal limits at the following control. There was no correlation between T3, T4 and TSH with the duration of HGH therapy. There was no significant difference between the groups of children treated with the different HGH doses. These data seem to demonstrate that the risk of inducing an alteration in thyroid function in hypopituitary patients during HGH treatment is very slight, and that the irregularly abnormal thyroid indices observed in some of the children during one of the controls might be an expression of their metabolic status at that moment.

Human beings have essentially two peptides with somatomedinic effect: insulin-like growth factor I (IGF I), somatomedin C (SmC) and IGF II. IGF II does not seem to play a significant role in postnatal growth. IGF I/SmC assay has been used in an attempt to identify GH-deficient subjects. A significant overlap in IGF I/SmC values between subjects with GH deficiency and normal children does not permit screening of pituitary patients. In addition to GH deficiency, low SmC values have been found in some short children with normal GH release to pharmacologic tests. It has been hypothesized that insufficient GH release in these subjects is not detected by the traditional tests. Replacement therapy has been suggested but the results are indefinite. IGF I/SmC assay is highly useful in the diagnosis and monitoring treatment for acromegaly.

The behavior of the secretion of ACTH, GH, and plasma cortisol during the insulin-induced hypoglycemia test on normal and obese children was studied. The secretion of the above-mentioned hormones was determined by calculating the integrals of the curves. The mean values of the integrals of the plasma cortisol and ACTH curves do not show any significant differences between the two groups of children. The mean values of the ratios between the integrals of the plasma cortisol and ACTH curves show a significant difference between the two groups (P smaller than 0.01). Since the mean values of the integrals of the plasma cortisol curves are practically the same in both groups, the difference in the above-mentioned ratios refers to the lower values of the integrals of the ACTH curves found in the obese children. This enables us to make the hypothesis that in the obese child the function of the pituitary-adrenal axis, at least during the insulin test, does not differ from the norm thanks to the adaptation of the ACTH secretion to the greater sensitivity of the adrenal glands to this hormone. In both the groups examined there was no correlation between the secretion of ACTH and plasma cortisol, between ACTH and GH, and between plasma cortisol and GH.

A case of congenital hypopituitarism with microphallus and severe neonatal hypoglycemia is described. The results of the clinical examination and of the tests of hypothalamo-pituitary function are discussed. It is reported that with GH replacement therapy a considerable growth of the penile size was obtained. The importance of evaluating the pituitary function in patients with micropenis and neonatal hypoglycemia is emphasized.

To evaluate the effects of two different doses of cranial irradiation on growth and growth hormone (GH) release, we studied 61 children with acute lymphocytic leukemia who had survived at least five years in continuous complete remission. Forty-three children received 24 Gy (group 1) and 18 children received 18 Gy (group 2). Height was evaluated at diagnosis, at the end of treatment, and 6, 12, and 24 months later. Growth hormone release was evaluated by arginine and levodopa tests after the end of treatment. After diagnosis, the height SD score decreased significantly in both groups; two years after the end of treatment, only group 1 showed an SD score for height that was still significantly lower than at diagnosis. Group 1 showed impaired GH responses to the tests and, compared with controls, group 1 in fact included a percentage of subjects with a normal response to levodopa (ie, greater than 8 micrograms/L) that was significantly lower (56.4% vs 83.3%) and a percentage of nonresponders to both tests that was significantly higher (21.6% vs 0%). These data indicate that only patients treated with lower cranial irradiation dosage (18 Gy) had complete growth recovery and normal GH responses to pharmacologic tests.

Twenty-one prepubertal children of small stature, 10 boys and 11 girls, aged from 4-3 to 12-8 years, were studied. Their height was less than 3rd centile, and during the preceding year all had a growth rate less than 4-5 cm/year. Arginine and L-dopa tests were given, and the release of growth hormone (GH) during monitored sleep was investigated. On the basis of the electroencephalogram and horizontal electro-oculogram, sleep was divided into stages 1-2-3-4 and rapid-eye-movement. All the children had a GH response greater than 8 ng/ml in at least one of the two pharmacological tests, and were therefore accepted as not suffering from GH deficiency. In all 21 children during sleep there was at least one secretory peak with GH greater than 8 ng/ml. Of a total of 46 secretory peaks recorded, 22 (48%) took place during deep, slow sleep (stages 3-4), 10 (22%) during light sleep (stage 2), 10 (22%) during REM sleep, and 4 (8%) during wakening. In 4 patients (19%) no secretory peak was observed during stages 3-4, even though there were peaks at other times. The data (a) show that it is essential to monitor GH throughout the night to ascertain with certainty the presence or absence of physiological secretory peaks of GH; (b) emphasise the rare disagreement between pharmacological and physiological tests; (c) suggest the use of this physiological test for GH secretion in those cases where the insulin test may be hazardous.

Growth hormone (GH) release with pharmacological tests and sleep test, somatomedin C and auxological features were studied in 10 patients affected by Duchenne Muscular Dystrophy. GH release in these patients seems to be lower than normal; moreover some of them are of short stature without an evident relationship with GH deficit. The possible significance of the data obtained is discussed, particularly in relation to the clinical course of the disease, and to current therapeutic trials with a GH release inhibitor (mazindol).

--43 neonates, born vaginally after spontaneous labor between the 38th and the 42nd week of pregnancy, were examined. GH and ACTH levels were assayed in 14 newborn infants. LH and FSH were determined in the remaining 29 patients (16 boys and 13 girls). Samples were collected from all infants for the assay of the above mentioned hormones at the 2nd, 6th, 12th and 24th hour of life, then every day for 7 consecutive days. During the whole first week of life plasma GH gave values that were significantly higher than those found in subjects over four years of age. The highest mean value of plasma ACTH was found at the 2nd hour of life (162.2 +/- 34.1 pg/ml). Then, there is a significant fall in the hormone level beginning with the 12th hour (p less than 0.01). Minimum level was reached on the 7th day. Plasma hCG-LH presents its maximum mean value at the 2nd hour, both in boys and girls (48.5 +/- 16.2 and 33.0 +/- 24.9 mU/ML, respectively). after this, plasma hCG-LH decreases progressively. No significant differences between the two sexes were found. Even though the mean values of plasma FSH do not change significantly during the whole test period, they do demonstrate a sex difference (significantly higher values in the females) from the fifth day afterwards.