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G Chiumello

Publications and source records attributed to G Chiumello.

At least 91 records · Page 5Linked to original sources
PubMed1995

Role of magnetic resonance imaging in hypothalamic-pituitary disorders.

Improvement of MRI diagnostic accuracy in the study of the hypothalamic-pituitary region provides precise anatomic details. In pituitary dwarfism, MRI reveals severe sella/pituitary gland and stalk hypoplasia with or without posterior pituitary ectopia, and empty sella, and this more frequently in patients with multiple pituitary hormone deficiency. Two main hypotheses have been proposed to explain these findings: traumatic stalk transection during breech delivery, and abnormal embryonic development of the pituitary gland. The association between neuroradiological findings and type/severity of endocrine alteration has not yet been clarified. In diabetes insipidus, MRI findings are normal picture, posterior lobe not visible, and thickened stalk (as expression of preclinical/initial histocytosis). Patients with central precocious puberty or hypogonadotropic hypogonadism rarely show morphologic abnormalities (hamartoma of the tuber cinereum, partially empty sella). So far, MRI permits one to identify morphologic pictures in diseases previously considered 'idiopathic'.

Humans↗
PubMed1994

Disseminated intravascular coagulation and severe peripheral neuropathy complicating ketoacidosis in a newly diagnosed diabetic child.

Disseminated intravascular coagulation is a very rare complication of diabetic ketoacidosis. Central nervous system palsy but not peripheral neuropathy has been reported in these patients. On the other hand, signs of peripheral neuropathy may also be present at the onset of diabetes, but they are usually reversible within a few days after correction of the metabolic derangement. We describe an unusual case of mononeuritis multiplex syndrome still present after 2 months of follow-up in a child with diabetic ketoacidosis complicated by disseminated intravascular coagulation at the onset of insulin-dependent diabetes. These neurological impairments may be consistent with functional neural lesions due to vasa nervorum thrombosis and prolonged ischaemia.

Blood Pressure↗
PubMed1994

Indications for a more aggressive disease process in newly diagnosed insulin-dependent diabetic children in northern than in southern Europe.

Finland and Sweden have the highest incidence of insulin-dependent diabetes in children in the world, about 3-4 times that of countries in the Mediterranean area, with the exception of Sardinia. We have collected information from several European clinics and from Pittsburgh, USA, in order to find out whether this difference incidence is associated with corresponding differences of the disease pattern. Patients in Finland or Sweden ('North') and Pittsburgh were younger (< 10 years old) at diagnosis compared with those in the other clinics in Europe (P < 0.05 versus P < 0.02). In the North, boys were in excess (58%) in contrast to France (40%) and Pittsburgh (46%). Patients in the North had a shorter duration of symptoms (< 8 days; P < 0.001) and higher blood glucose (> 20 mmol/l; P < 0.05) than those attending the other European clinics. Irrespective of age, there were more ICA-positive patients in the North (94%) than in Berlin-Vienna (67%; P < 0.01) or in France (70%; P < 0.01). There was a tendency for non-diabetic parents and siblings in the North to have lower C-peptide values (< 0.26 pmol/ml) at the time of diagnosis of the proband and to be ICA-positive more often than relatives in the other European clinics. The seasonal variation of diagnosis showed no obvious geographical differences, with recorded diagnosis always lowest during the summer. We conclude that certain factors seem to cause not only a high incidence of diabetes in children in Finland and Sweden but perhaps also a more aggressive early disease process.

Adolescent↗
PubMed1994

A dosage sensitive locus at chromosome Xp21 is involved in male to female sex reversal.

Male to female sex reversal has been observed in individuals with duplications of the short arm of the X chromosome. Here we demonstrate that sex reversal results from the presence of two active copies of an Xp locus rather than from its rearrangement and that alterations at this locus constitute one of the causes of sex reversal in individuals with a normal 46,XY karyotype. We have named this locus DSS (Dosage Sensitive Sex reversal) and localized it to a 160 kilobase region of chromosome Xp21, adjacent to the adrenal hypoplasia congenita locus. The identification of male individuals deleted for DSS suggests that this locus is not required for testis differentiation. We propose that DSS has a role in ovarian development and/or functions as a link between ovary and testis formation.

Chromosome Mapping↗
PubMed1994

Post-exercise albuminuria does not predict microalbuminuria in type 1 diabetic patients.

To investigate whether post-exercise urinary albumin excretion in Type 1 diabetic children and adolescents may prospectively predict the development of microalbuminuria, we have assessed post-exercise urinary albumin excretion before and after 6.2 +/- 1.7 years of follow-up in 66 diabetic children and adolescents. Post-exercise urinary albumin excretion rose significantly above the pre-exercise values in diabetic patients by 2.7 (-3.8 to 84.2) micrograms min-1 (p < 0.001) and in a group of 9 healthy individuals by 3.9 (-0.7 to 13.7) micrograms min-1 (p < 0.02) without significant differences between groups. Post-exercise albuminuria was greater in postpubertal than prepubertal 9.8 vs 4.3 micrograms min-1 (p < 0.03) and pubertal 9.8 vs 6.0 micrograms min-1 (p < 0.02) patients; post-exercise changes in urinary albumin excretion were also positively related to glycated haemoglobin (r = 0.293; p < 0.05). Eight out of 66 patients developed microalbuminuria at follow-up. Urinary albumin excretion at follow-up was comparable between patients with normal and abnormal post-exercise urinary albumin excretion; moreover post-exercise urinary albumin excretion was within the normal range in 5 out of 8 patients with microalbuminuria at follow-up. In conclusion post-exercise albuminuria does not seem to be a useful predictor of the onset of microalbuminuria in Type 1 diabetic children and adolescents.

Adolescent↗
PubMed1994

Spontaneous growth and pubertal development in Turner's syndrome with different karyotypes.

We studied spontaneous growth and pubertal development in 205 girls with Turner's syndrome, aged 1 month to 28.16 years, according to different karyotypes: 45,X (52%), X-mosaicism (12%), X-structural abnormalities (36%). Data on height, weight, height velocity, bone age and pubertal development were collected yearly in a mixed longitudinal and cross-sectional mode. Pelvic ultrasonography was performed in 133 patients, 46 of whom had contact breast thermography. Standards for height and height velocity (1-20 years) showed no differences when compared with other studies. Some differences were found when these data were subdivided by karyotype. In fact, X-mosaicism subjects had a pubertal growth spurt between 8 and 12 years of age. The spurt observed in this group cannot be justified by the more frequent presence of residual ovarian activity alone. It also appears in patients without ovaries and confirms the influence of a genetic factor on the X-chromosome. In spite of this spurt, the greatest final height was reached by 45,X subjects. X-mosaicism girls had more frequent spontaneous breast development linked to a higher percentage of visible ovaries. In this group the age of the first pubertal signs was similar to that of normal subjects and occurred much earlier than in the other groups.

Adolescent↗
PubMed1994

Persisting functional connection in growth-hormone-deficient patients with a transected stalk.

Prolactin response after domperidone (DOM) stimulus was used to investigate the functional status of the hypothalamo-hypophyseal axis in 57 congenital growth-hormone-deficient (GHD) children with and without magnetic resonance imaging (MRI) abnormalities. Response to DOM was significantly lower in the GHD children compared with controls, using maximum peak (p < 0.0001), increase (p < 0.0001) or percentage increase (p < 0.05). The lowest values were observed in patients with hypophyseal stalk transection. Thus, the DOM test revealed reduced dopaminergic transmission in GHD subjects, more severe in the transected group, in whom, however, a response to the stimulus was still present. Therefore, it seems that a residual hypothalamo-hypophyseal connection is preserved even if it is not detectable with MRI.

Adolescent↗
PubMed1994

[Thyroid autoimmunity and congenital hypothyroidism].

The involvement of thyroid autoimmunity in the pathogenesis of sporadic congenital hypothyroidism is still incompletely understood. While antithyroglobulin and anti-thyroperoxidase antibodies are harmless, the transplacental passage of TSH receptor antibodies with blocking activity from a mother with autoimmune thyroiditis to the fetus is responsible of transient neonatal hypothyroidism in the baby. This is however a rare condition. Thyroid growth blocking antibodies have been described in healthy mothers of children with permanent congenital hypothyroidism due to thyroid dysgenesis, but this observation was not confirmed in other studies including our own. Antibodies producing cell mediated cytotoxicity (ADCC), either transferred from the mother or due to an autoimmune thyroiditis developing in utero, might be involved in the pathogenesis of permanent congenital hypothyroidism. However, this hypothesis requires confirmation in more extensive studies.

Autoimmune Diseases↗
PubMed1994

Peripheral and abdominal adiposity in childhood obesity.

The aim of this work was to evaluate peripheral and abdominal adipose tissue (AT) content detected by MRI in normal weight and obese children, to compare MRI data with simple anthropometric indexes and to estimate intrabdominal adipose tissue (IAT) influence on cardiovascular risk factors. The subjects were 23 obese and 21 normal weight children aged 10 to 15 years. The following measurements were carried out: MRI analysis at lumbar level with definition of subcutaneous adipose tissue (SAT) area and IAT area; arm fat area (AFA); thigh fat area (TFA) and waist/hip ratio from anthropometry. SAT (353 +/- 94 cm2) was predominant compared with IAT (49 +/- 21 cm2) in obese as well as in controls (SAT: 79 +/- 61 cm2; IAT: 22 +/- 11 cm2). No differences in SAT/IAT ratio were found for sex and puberty, either in obese subjects or in controls. SAT and IAT were significantly related in controls (r = 0.77, P < 0.0001), but not in obese subjects (r = 0.12, P = 0.59). IAT was related to total and LDL cholesterol and triglycerides levels (r = 0.54, P < 0.02, r = 0.60, P < 0.01, r = 0.46, P < 0.04, respectively) in obese children. AFA and TFA from anthropometry significantly underestimated AT compared with MRI in both groups. Methods agreement analysis showed unacceptable results for anthropometry. It was concluded that childhood obesity has a subcutaneous adipose pattern with no differences between the sexes. IAT already begins to have clinical significance since it has a relationship to some cardiovascular risk factors.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdomen↗
PubMed1994

Evidence of a congenital midline brain anomaly in pituitary dwarfs: a magnetic resonance imaging study in 101 patients.

BACKGROUND: Magnetic resonance imaging (MRI) of the brain in pituitary dwarfs has revealed a previously unknown entity: ectopia of the posterior pituitary (PPE), absence or hypoplasia of the pituitary stalk and hypoplasia of the anterior pituitary. The pathogenesis of these findings was explained originally by a traumatic transection of the pituitary stalk during delivery. A high incidence of breech delivery has been reported in these groups, but the traumatic hypothesis cannot explain the findings in the relatively high percentage of patients with normal delivery, nor account for a different feature also found in other pituitary dwarfs consisting of pituitary hypoplasia with normal posterior pituitary. A second hypothesis could then been proposed, based on dysgenesis or abnormal embryonic development of both adenohypophysis and neurohypophysis. OBJECTIVE: To review the value and significance of these two different etiopathogenetic hypotheses by analyzing clinical, endocrinological, and MRI findings in a large population of pituitary dwarfs. METHODS: One hundred and one consecutive patients with congenital idiopathic growth hormone deficiency (CIGHD) were studied by MRI; they were compared with a control group of 46 healthy short children. A complete clinico-endocrinological evaluation was obtained in both patients and controls to assess the perinatal history, the pituitary-hypothalamic function, and the neurological status. MRI studies were evaluated both qualitatively and quantitatively and the pituitary volume (PV) was calculated in both patients and controls. Quantitative data were statistically analyzed to compare the mean PV of the patients with the mean PV of controls, the hormonal therapy, the single or multiple pituitary hormone deficiency, and the presence of breech delivery. RESULTS: MRI revealed PPE in 59 patients and a normal posterior pituitary (NPP) in 42. PV was extremely small in patients with PPE and in patients with NPP associated with a severely narrowed pituitary stalk; mean PV was significantly lower in CIGHD patients when compared with that of healthy short children. PV was not influenced by hormonal therapy and did not differ between patients with single and multiple pituitary hormone deficiency and between patients with normal and breech delivery. PPE patients differed from NPP patients for a higher male/female ratio (3:1 vs 1:1) and for a greater frequency of multiple pituitary hormone deficiency (49% vs 12%), breech delivery (32% vs 7%), and associated congenital brain anomalies (12% vs 7%). In PPE patients breech delivery was strongly associated with multiple pituitary hormone deficiency. CONCLUSION: On the basis of this study the traumatic hypothesis could theoretically explain the pathogenesis of PPE only in 32% of the patients with this condition. On the basis of modern understanding of embryogenesis of anterior and posterior pituitary, it is then justified to propose that a defective induction of mediobasal structure of the brain in the early embryo could account for both the complex morphological MRI abnormality and the clinico-endocrinological features encountered in all PPE patients. The close contiguity between the future pituitary and hypothalamus, the peculiar association with congenital midline brain anomalies, and the recent data about a possible role of Pit-1 gene, all support the hypothesis of a congenital defect. Finally, breech delivery can be considered not as a cause of PPE, but as an effect of the embryonic pituitary-hypothalamic abnormalities.

Adolescent↗
PubMed1993

Effect of gluten-free diet on bone mineral content in growing patients with celiac disease.

Osteoporosis is a complication of celiac disease in adulthood, but little is known about the influence of the disease on bone mineralization in children. In the present study we evaluated radial bone mineral content (BMC) in celiac children and adolescents at diagnosis and after they consumed a gluten-free diet (GFD). The BMC values of 33 celiac patients at diagnosis were significantly lower than those of 255 control subjects (P < 0.001). There was no difference between diabetic and non-diabetic celiac patients. In 14 patients the BMC increased significantly (P < 0.05, ANCOVA) after 1.28 y of GFD. In these patients the mean annual BMC increment was 0.07 g/cm, significantly greater (P < 0.05) than the increment of normal growing children (0.05 g.cm-1.y-1). Our data indicate that although osteoporosis complicates celiac disease during childhood and adolescence, GFD alone is able to remarkably improve bone mineralization.

Bone Density↗
PubMed1993

Types, stability, and phenotypic consequences of chromosome rearrangements leading to interstitial telomeric sequences.

Using in situ hybridisation, we identified interstitial telomeric sequences in seven chromosomal translocations present in normal and in syndromic subjects. Telomeric sequences were also found at the centromeric ends of a 4p and a 4q caused by centric fission of one chromosome 4. We found that rearrangements leading to interstitial telomeric sequences were of three types: (1) termino-terminal rearrangements with fusion of the telomeres of two chromosomes, of which we report one case; (2) rearrangements in which an acentric fragment of one chromosome fuses to the telomere of another chromosome. We describe four cases of Prader-Willi syndrome with the 15q1-qter transposed to the telomeric repeats of different recipient chromosomes; (3) telomere-centromere rearrangements in which telomeric sequences of one chromosome fuse with the centromere of another chromosome. We describe two examples of these rearrangements in which not only telomeric sequences but also remnants of alphoid sequences were found at the fusion point. Instability at the fusion point of the derivative chromosome was found in the Prader-Willi translocations but we were unable to correlate this instability with culture conditions. The two subjects with the termino-terminal rearrangement and the centric fission respectively have normal phenotypes. The two patients with telomere-centromere fusions were unbalanced for the short arm of an acrocentric chromosome and had failure to thrive; one of them also had dysmorphic facies. We postulate that these phenotypes could be the result of uniparental disomy.

Chromosome Aberrations↗
PubMed1993

Decrease of glomerular hyperfiltration in short-term diabetic adolescents without microalbuminuria.

OBJECTIVE: This study has been designed to follow prospectively the GFR and UAE of young patients with short-term IDDM and normal UAE. RESEARCH DESIGN AND METHODS: The study population consisted of 19 patients with glomerular hyperfiltration and 19 patients with normal GFR, matched for duration of diabetes and age. GFR has been assessed by radioisotopic tracer and UAE by RIA at the beginning of the study and after 30.5 +/- 10.4 mo of follow-up. RESULTS: GFR decreased in the two groups btt delta GFR of patients with glomerular hyperfiltration was greater than delta GFR of patients with normal GFR (0.83 +/- 0.55 vs. 0.28 +/- 0.63 ml.min-1.mo-1; P < 0.01). UAE, BP, and prevalence of microalbuminuria were comparable between the two groups at follow-up. Rate of fall of GFR was positively correlated with initial GFR (r = 0.59, P < 0.001) but not with initial UAE, BP, or changes in HbA1C, UAE, BP, or pubertal development during follow-up. CONCLUSIONS: Investigation of kidney function in children and adolescents with IDDM over a 3-yr follow-up period shows that glomerular hyperfiltration is characterized by a greater decline in GFR without an increased rate of appearance of microalbuminuria, than in patients with normal GFR.

Adolescent↗