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D Larizza

Publications and source records attributed to D Larizza.

At least 37 records · Page 2Linked to original sources
PubMed1996

Growth hormone response to growth hormone-releasing hormone varies with the hypothalamic-pituitary abnormalities.

We determined growth hormone (GH) and insulin-like growth factor I (IGF-I) levels after a 3 h infusion of escalating doses of growth hormone-releasing hormone (GHRH(1-29)) followed by a bolus injection in hypopituitary patients with marked differences in pituitary features at magnetic resonance imaging (MRI) in order to evaluate further the contribution of MRI in the definition of pituitary GH reserve in GH-deficient patients. Twenty-nine patients (mean age 14.5 +/- 4.0 years) were studied. Group I comprised 13 patients: seven with isolated GH deficiency (IGHD) (group Ia) and six with multiple pituitary hormone deficiency (MPHD) (group Ib) who had anterior pituitary hypoplasia, unidentified pituitary stalk and ectopic posterior pituitary at MRI, Group II consisted of eight patients with IGHD and small anterior pituitary/empty sella, while in group III eight had IGHD and normal morphology of the pituitary gland. Growth hormone and IGF-I levels were measured during saline infusion at 08.30-09.00 h, as well as after infusion of GHRH (1-29) at escalating doses for 3h: 0.2 micrograms/kg at 09.00-10.00 h, 0.4 micrograms/kg at 10.00-11.00 h, 0.6 micrograms/kg at 11.00-12.00 h and an intravenous bolus of 2 micrograms/ kg at 12.00 h. In the group I patients, the peak GH response to GHRH(1-29) was delayed (135-180 min) and extremely low (median 2mU/l). In group II it was delayed (135-180 min), high (median 34.8 mU/l) and persistent (median 37.4 mU/l at 185-210 min). In group III the peak response was high (median 30.8 mU/l) and relatively early (75-120 min) but it declined rapidly (median 14.4 mU/l at 185-210 min). In one group I patient, GH response increased to 34.6 mU/l. The mean basal value of IGF-I levels was significantly lower in group I (0.23 +/- 0.05 U/ml) than in groups II (0.39 +/- 0.13U/ ml, p < 0.01) and III (1.54 +/- 0.46 U/ml, p < 0.001) and did not vary significantly during the GHRH(1-29) infusion. The present study demonstrates that the impaired GH response to 3 h of continuous infusion of escalating doses of GHRH(1-29) was strikingly indicative for pituitary stalk abnormality, strengthening the case for use of GHRH in the differential diagnosis of GH deficiency. The low GH response, more severe in MPHD patients, might be dependent on the residual somatotrope cells, while the better response (34.6 mU/l) in the group Ia patients might suggest that prolonged GHRH infusion could help in evaluating the amount of residual GH pituitary tissue. Pituitary GH reserve, given the GH response to GHRH infusion in GH-deficient patients with small anterior pituitary/empty sella, seems to be maintained.

Diagnosis, Differential↗
PubMed1994

Balanced autosomal translocations and ovarian dysgenesis.

We report two unrelated women with gonadal dysgenesis, and a (6;15)(p21.3;q15) and a (8;9)(p11.2;q12) balanced translocation, respectively. The patients were of normal stature and showed no phenotypic abnormality or malformation other than ovarian failure. We are not aware of other reports of balanced autosomal translocations associated with gonadal dysgenesis in women. The occurrence of chromosome anomaly and sterility in the two females may be coincidental. However, studies on mouse gametic progression indicate that balanced autosomal translocations can cause oocyte degeneration and reduction of reproductive lifespan. On the basis of these observations, we cannot exclude that the ovarian failure in our patients is the result of oocyte degeneration because of as yet unidentified consequences of the balanced translocations.

Adolescent↗
PubMed1994

Adrenocorticotrophin stimulation and HLA polymorphisms suggest a high frequency of heterozygosity for steroid 21-hydroxylase deficiency in patients with Turner's syndrome and their families.

OBJECTIVE: Following the chance observation of congenital adrenal hyperplasia in a patient with Turner's syndrome we decided to evaluate the incidence of 21-hydroxylase deficiency (21-OHD) in patients with Turner's syndrome and in their relatives. SUBJECTS: Fifty-two patients with Turner's syndrome (mean age +/- SD 14.7 +/- 5.6 years) and 26 relatives were studied. MEASUREMENTS: 17-Hydroxyprogesterone (17-OHP) serum levels before and after i.m. administration of 0.25 mg of ACTH(1-24) were evaluated in patients with Turner's syndrome and relatives. In Turner patients basal testosterone and dehydroepiandrosterone concentrations were determined. The results of ACTH tests were analysed according to HLA class I and II alleles of subjects. RESULTS: The baseline 17-OHP was in the range of the classical form of 21-OHD in one Turner patient, who had severe clitoral enlargement since birth. In 11 patients the stimulated 17-OHP serum level was higher than in normal controls and similar to that found in 21-OHD heterozygous subjects. Clitoral enlargement was significantly more frequent in patients with high stimulated 17-OHP levels (P < 0.001). The frequency of heterozygous-type responses was higher in Turner subjects (1:4.6) than in the Italian population (1:47 for the classic form and 1:9.5 for the non-classic form of the disease). In our patients the frequencies of HLA antigens and haplotypes, usually associated with 21-OHD, were different compared to the controls. HLA-B8, which is negatively associated to 21-OHD, was less frequent in Turner patients than in controls and absent in those with an elevated 17-OHP level. HLA-B14, B22 and B35 were more frequent, though not significantly so, in Turner patients than in controls and even more so in the group with an elevated 17-OHP level. The same investigations performed in 26 relatives of the Turner patients showed a high frequency of carriers of 21-OHD and three subjects with the cryptic form of the disease. CONCLUSIONS: Although in the literature there are only two reports of the association of Turner's syndrome and 21-OHD, on the basis of our experience this association was more frequent, in the Italian population. Since some of the typical signs of 21-OHD (short final stature, varying degrees of virilization, menstrual irregularities, amenorrhoea, infertility) in patients with Turner's syndrome could also be attributed to the chromosomal abnormality, it is therefore more difficult to diagnose 21-OHD in Turner subjects. Adrenal function should be assessed, at least in the presence of clitoral enlargement, in patients with Turner's syndrome, particularly if their karyotype does not contain a Y chromosome. The hypothesis of the presence of cryptic Y chromosome material in these patients should also be considered.

17-alpha-Hydroxyprogesterone↗
PubMed1994

Turner's syndrome in Italy: familial characteristics, neonatal data, standards for birth weight and for height and weight from infancy to adulthood.

In 1990, the Italian Study Group for Turner's Syndrome (ISGTS) undertook a nationwide survey, involving the retrospective collection of cross-sectional data and longitudinal growth profiles of 772 girls with Turner's syndrome born between 1950 and 1990. The study was carried out in 29 pediatric endocrinological centers. In this first report, the familial characteristics and neonatal data of Turner girls are described, compared to those of the general population, and related to postnatal somatic development. Furthermore, charts for birth weight and growth standards for height and weight from infancy to adulthood are presented (these are the first charts based on a large sample from the Mediterranean area). The main findings were: (1) incidence of Turner births increases with parental age or parity; (2) most of the neonates are small for dates; (3) girls with normal birth weight tend to be both taller and heavier than girls with low birth weight during the whole growth period; and (4) a 10-cm difference in midparental height leads to a 6.5-cm difference in adult stature.

Adolescent↗
PubMed1994

Molecular analysis of CYP21 gene mutations carried on HLA-B14 positive haplotypes.

HLA-B14 positive haplotypes have increased frequencies in a group of patients with puberty disorders, IgA deficiency and cancer of the ovary. Clinical investigations demonstrated that all these patients have high values of 170H progesteron after the ACTH test which suggests an alterated function of 21 hydroxylase enzyme. In order to investigate whether these B14 positive haplotypes carry the same CYP21 mutation in the various diseases and controls, we have amplified by polymerase chain reaction (PCR) the sections of CYP21B gene which include amino acid positions 172 and 281 where typical mutations are known to occur in 21 hydroxylase deficiency. The presence or absence of the defined mutations was tested by oligonucleotide hybridization using oligonucleotides, labelled with DIG-ddUTP, designed to hybridize with the mutated or with the normal sequence. It was found that regardless of whether the subject tested was a patient or a healthy control the mutation at position 281 was found in all cases carrying HLA-B14, DR1 haplotype. Interestingly, this mutation does not seem to be in association with HLA-B14, DR7 haplotype. These findings suggest that CYP21 gene plays a role in all these differing diseases although it must be stressed that there may be alternative explanations for the observed data.

Adolescent↗
PubMed1993

Hypogonadism in a patient with balanced X/18 translocation and pituitary hormone deficiency.

The case of a girl carrying a balanced X/autosome translocation: 46,X,t(X;18)(q22.3;q23),inv(9)(p11q13) and pituitary hormone deficiency (growth hormone and gonadotropin) is described. The patient had a doll-like facies, with frontal bossing and poor development of the nasal bridge, increased adipose tissue especially of the trunk, short stature and absence of pubertal development without Ullrich-Turner stigmata apart from urinary tract malformation. The lack of spontaneous puberty seems related both with gonadotropin deficiency, as suggested by hormonal data and MRI of the pituitary region, and with gonadal dysgenesis, due to the X/autosome translocation, involving the critical region of the X chromosome essential for normal ovarian function. Growth velocity was unsatisfactory during growth hormone treatment; a higher dose of growth hormone similar to that used in Ullrich-Turner patients, would probably have improved her growth rate.

Child, Preschool↗
PubMed1993

Diagnosing growth hormone deficiency: the value of short-term hypocaloric diet.

In the attempt to define possible causes of false positive GH deficiency, the role of caloric intake on GH determination was explored. The serum GH responses to insulin-induced hypoglycemia or arginine were assessed before and after 3 days of a hypocaloric diet in 23 prepubertal children of normal weight, aged 6.7-11.9 yr. Seventeen had short stature and a GH response to insulin and arginine below 10 micrograms/L, and 6 controls had normal stature and a GH peak above 10 micrograms/L in response to arginine. After diet, the serum peak GH and the area under the curve increased in both the patients (P < 0.0005 and P < 0.0005) and the controls (P < 0.005 and P < 0.025) with a GH peak greater than 10 micrograms/L in 11 of 17 patients. The patients with a persistent GH response below 10 micrograms/L also had lower mean 12-h overnight GH levels (P < 0.0005), whereas those with a normal GH response after diet had an overnight GH level greater than 3 micrograms/L. In the patients, the mean nighttime GH concentrations correlated with the serum GH peak (r = 0.85; P < 0.005) and with the area under the curve after the diet (r = 0.65; P < 0.025). The diet induced changes in plasma insulin-like growth factor-I, GH-releasing hormone levels, basal blood sugar and the nadir level obtained during insulin stimulation, total T3, and rT3. Height increased significantly during 1 and 2 yr (P < 0.005) of GH treatment only in patients with a GH response below 10 micrograms/L after the diet. These data are consistent with the hypothesis that the GH response to stimulation is strongly calorie dependent and that 3 days of a hypocaloric diet can increase the number and height of GH peaks and the total GH responses to insulin and arginine. The clear correlation of the GH response to stimulation after a hypocaloric diet with the mean nighttime GH and also with the growth response to GH treatment indicates that GH deficiency may be overdiagnosed in many children with short stature.

Arginine↗
PubMed1992

Influence of HLA genotype on birth weight of patients with Turner syndrome.

Growth failure starting before birth is a common characteristic in Turner syndrome, and its pathogenesis is still not completely explained. Experiments performed in mice and rats to test whether a genetic disparity between mothers and offspring and maternal immunological status have any influence on litter size have demonstrated that allogenic litters are significantly larger in size than genetically compatible ones. Studies in humans have given contrasting results, but some authors have found that heterozygosity at enzyme loci and in blood groups is positively correlated with intrauterine growth. HLA class I and II polymorphisms were defined in 53 patients with Turner syndrome and in their parents, and lymphocytotoxic antibody detection was performed in 36 mothers. These data were related to the patients' birth weight. The frequency of the HLA-B16 allele in patients with a birth weight greater than 10th centile was significantly higher in comparison with those less than 10th centile. HLA antigen sharing was present in 43 couples (81.1%). Mean birth weight was 2934 +/- 472 g in patients without HLA antigen parental sharing and 2721 +/- 529 g in those whose parents shared HLA antigens. The mean birth weight of the 10 patients whose parents do not share HLA antigens was significantly higher than that of the patients with parental HLA-B+ DR sharing (P less than 0.05) and not significantly highe than in those patients with parental HLA sharing at other HLA loci. Patients whose parents shared B+DR antigens also had significantly smaller birth weights than those with B and A+B+DR sharing (P less than 0.025 and P less than 0.025). No significant difference in mean birth weight was found in relation to other parameters, such as mother-child histocompatibility, HLA homozygosity and lymphocytotoxic production in the mothers.

Antibody Formation↗
PubMed1992

Correlation between magnetic resonance imaging of posterior pituitary and neurohypophyseal function in children with diabetes insipidus.

The posterior pituitary lobe and stalk were studied by magnetic resonance imaging in 20 children with diabetes insipidus of different origins: primary familial autosomal dominant (n = 2) or idiopathic (n = 2), and secondary to craniopharyngioma (n = 6, resected in 5), to Langerhans cell histiocytosis (n = 5), to excessive water intake (dipsogenic; n = 3), to renal vasopressin insensitivity (n = 1), and to osmoreceptor dysfunction (n = 1). Of the four children with primary diabetes insipidus, the posterior bright signal was recognizable in two with the familial autosomal dominant form and one with the idiopathic form; in the latter, the pituitary stalk was thin, while it was normal in the first two patients; no posterior hyperintense signal with enlarged and gadolinium-enhanced pituitary stalk was observed in the fourth. The posterior hyperintense signal was absent without evidence of ectopic posterior pituitary tissue regeneration in five children with surgically removed craniopharyngioma and was doubtful in the child with unresected craniopharyngioma; the stalk was unrecognizable in all patients. In the five children with Langherans cell histiocytosis, the posterior bright signal was absent, while the stalk was normal in two and unexpectedly enlarged in three (uniformly in two and mainly at the level of median eminence and hypothalamus in one). All five patients with dipsogenic or nephrogenic diabetes insipidus or osmoreceptor dysfunction had normal images of posterior pituitary lobe and stalk. Normal posterior pituitary bright signal and stalk were found in all 25 healthy control children. Plasma vasopressin was undetectable in all patients except in nephrogenic one, in the child with osmoreceptor dysfunction, and in two of three dipsogenic children, the third mimicking partial neurogenic diabetes insipidus.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1991

Effects of short-term administration of human chorionic gonadotropin on immune functions in cryptorchid children.

To delineate the effects of human chorionic gonadotropin (hCG) administration on immune responsiveness, immunological parameters including serum immunoglobulins, total and differential white blood cell count T and B lymphocyte membrane phenotype, in vitro, proliferative response to phytohaemagglutinin, Concanavalin A (ConA) and pokeweed mitogen were studied in 13 prepubertal cryptorchid boys before, during, and 3 months after hCG therapy. Before treatment, all the immunological parameters were normal except for an unexpected high percentage of T suppressor-cytotoxic cells (CD8+). During therapy, the absolute number of total peripheral blood lymphocytes, and that of total T-cells, T helper-inducer cells and of CD8+ subsets were diminished. The percentage of CD8+ cells and lymphocyte response to ConA decreased significantly and returned to normal after hCG withdrawal. The possible effects of long-term hCG treatment remain to be determined.

Child↗
PubMed1991

Hypopituitarism and stalk agenesis: a congenital syndrome worsened by breech delivery?

Thirty-seven patients with idiopathic hypopituitarism, of whom 12 had multiple pituitary hormone deficiencies (MPHD) and 25 isolated growth hormone deficiency (IGHD), were evaluated by magnetic resonance imaging (MRI). Twenty-two of the 37 showed congenital anterior pituitary hypoplasia, stalk agenesis and ectopic posterior pituitary gland at the infundibular recess (group A), while the remaining 15 presented isolated anterior pituitary hypoplasia (group B). Perinatal histories obtained from all patients demonstrated that 18/22 children of group A (81.81%) had histories of adverse perinatal events, with breech presentation in 15 (68.18%). Twelve of 12 children of group A born by breech delivery developed MPHD; 3 born by cesarean section for breech presentation had only IGHD. Patients of group B had also a high incidence of perinatal insults (12/15, 80%), but breech delivery was markedly less frequent (13.33 vs. 68.18% of group A) and responsible for only IGHD. Group B had also higher percentages of maternal spontaneous abortion and low birth weight. Our study suggests that several factors may play a role in the development of growth hormone deficiency. Some patients had severe perinatal insults apparently leading to hypopituitarism. We were able to define by MRI a group of patients with congenital abnormalities, such as anterior pituitary hypoplasia, stalk agenesis and posterior pituitary ectopia, among whom breech presentation was very common. In this group, breech delivery was always followed by MPHD while cesarean or normal delivery in such patients was followed by IGHD only.

Adult↗
PubMed1991

Hypothalamic-pituitary dysfunction in growth hormone-deficient patients with pituitary abnormalities.

Hypothalamic-pituitary function was studied in 45 patients with idiopathic GH deficiency (GHD), 33 of whom had pituitary abnormalities on magnetic resonance imaging: pituitary hypoplasia, undescended stalk and ectopia of the posterior lobe in 8 patients with isolated GHD (IGHD) (group I) and in 12 patients with multiple pituitary hormone deficiency (MPHD) (group II); isolated pituitary hypoplasia in 13 patients with IGHD (group III); no evidence of pituitary abnormalities in the remaining 12 patients with IGHD (group IV). Sellar and pituitary volumes were significantly lower in groups I, II, and III than in group IV (P less than 0.001). No significant differences were observed between group I and group II in the GH response to GHRH1-44 expressed both as peak serum GH and area under the curve. Mean GH peak in group III and IV was significantly higher than that in group I (P less than 0.005) and II (P less than 0.001), as were the mean AUC (P less than 0.005), suggesting hypothalamic defect. Delayed peak serum TSH after TRH was found in all patients of group II, and overt hypothyroidism in 11 of them. Furthermore, basal hyperprolactinemia was present in 6 patients and adrenal insufficiency in 7 cases of group II. Finally, a reduced response of FSH to GnRH was observed in all these patients (P less than 0.005 vs. each of the other groups), and clinical hypogonadism was present in all of them. We suggest that: 1) A high incidence of pituitary abnormalities seems to be present in idiopathic GHD patients; 2) Pituitary hormone deficiencies are more dependent on the type of the hypothalamic-pituitary abnormality than on the size of the pituitary per se: the association of pituitary hypoplasia, undescended stalk and ectopia of the posterior lobe should possibly be considered a distinct entity reflecting an early abnormality in hypothalamic development; 3) The majority of patients with IGHD or MPHD probably have a primary hypothalamic releasing hormone deficiency even if pituitary hypoplasia is associated; 4) Magnetic resonance imaging may have a role in the diagnosis and prognosis of patients with GHD through differentiation between patients who are at risk for developing MPHD vs. those who are candidates for having a persistently isolated GHD.

Adolescent↗
PubMed1990

Hypothalamic-pituitary dwarfism: comparison between MR imaging and CT findings.

Magnetic Resonance (MR) imaging was carried out on 33 patients with idiopathic growth hormone deficiency, in 22 of whom CT scan had been carried-out previously. Twenty-one patients presented some complications at birth. Both MR and CT were positive in the evaluation of the sella. MR imaging exhibited a higher degree of accuracy than CT in the evaluation of pituitary gland, pituitary stalk and brain anomalies. On the basis of pituitary morphology demonstrated by MR imaging, and perinatal histories, a classification is proposed which divides our patients into three group: A) a first group of 13 patients presenting severe hypoplasia of the anterior pituitary lobe, hypoplasia of the stalk and ectopia of posterior lobe. The underlying cause of these anatomic defects might be developmental in origin, and date from early intrauterine life, probably worsened at birth. B) a second group of 10 patients presenting severe hypoplasia of the anterior pituitary lobe. A perinatal event and birth trauma might be responsible for pituitary damage. C) a third group of 10 patients with no morphological abnormalities of the pituitary gland. A derangement of the neuroendocrine mechanism which control the growth hormone secretion might account for these patients.

Adolescent↗
PubMed1990

The influence of dietary education in diabetic children.

The aim of our study was to evaluate the efficacy of dietary education in inducing modification of the diet and to measure biochemical parameters in 36 children and adolescents with IDDM. At the beginning of the study, each patient was evaluated as follows: food intake (by the method of the 24-h recall for 3 days), auxological parameters, biochemical parameters. Thereafter a program of nutritional guidelines was provided. Subsequent meetings took place at 1-month-intervals. The study ended 3 months later, when all the parameters were completely revalued. We observed improved nutrition in our patients both in terms of total caloric intake and calorie distribution. In particular there was an increase in carbohydrates and a reduction in lipids, reaching the percentage levels recently recommended. With a reduction in lipid intake a significant decrease in LDL cholesterol and a significant increase in HDL cholesterol were noticed in our patients. These modifications are very important for the prevention of arteriosclerosis and thus macrovascular disease. We maintain that dietary education plays an important role in helping children and adolescents with IDDM to follow a suitable diet.

Adolescent↗