Gonadotropin secretion in girls with turner syndrome measured by an ultrasensitive immunochemiluminometric assay.

BACKGROUND/AIM: Gonadotropin levels measured by radioimmunoassays are high in girls with Turner syndrome (TS), but overlap significantly with those of normal girls. We hypothesized that gonadotropin levels would be above the normal range in TS when measured by ultrasensitive assays. METHODS: Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were measured in 68 TS, and 133 control girls using ultrasensitive immunochemiluminometric assays (ICMA). RESULTS: FSH levels in TS and normal girls were highest in early childhood (56.0 +/- 39.7 and 2.3 +/- 1.8 IU/l, respectively), declined at 6-10 years of age (11.3 +/- 13.1 and 1.8 +/- 0.9 IU/l, respectively), and then increased again (104.4 +/- 68.9 and 4.9 +/- 2.4 IU/l, respectively). FSH was in the normal range on 11 of 27 occasions in TS girls with ages 5-10 years, and on 3 of 44 occasions in >10 years. Although average LH values were higher than those of controls, they often overlapped the normal range. CONCLUSION: A significant number of TS girls have normal gonadotropins by ICMA. Spontaneous gonadotropin levels are not an adequate screening test for the diagnosis of TS but may prove useful for predicting the gonadal function and determining the appropriate timing of estrogen replacement therapy.

Risk factors for congenital hypothyroidism: results of a population case-control study (1997-2003).

OBJECTIVE: To identify risk factors for permanent and transient congenital hypothyroidism (CH). DESIGN: A population-based case-control study was carried out by using the network created in Italy for the National Register of Infants with CH. METHODS: Four controls were enrolled for each new CH infant; 173 cases and 690 controls were enrolled in 4 years. In order to distinguish among risk factors for permanent and transient CH, diagnosis was re-evaluated 3 years after enrollment when there was a suspicion of transient CH being present. Familial, maternal, neonatal and environmental influences were investigated. RESULTS: An increased risk for permanent CH was detected in twins by a multivariate analysis (odds ratio (OR) = 12.2, 95% confidence interval (CI): 2.4-62.3). A statistically significant association with additional birth defects, female gender and gestational age >40 weeks was also confirmed. Although not significant, an increased risk of CH was observed among infants with a family history of thyroid diseases among parents (OR = 1.9, 95% CI: 0.7-5.2). Maternal diabetes was also found to be slightly associated with permanent CH (OR = 15.7, 95% CI: 0.9-523) in infants who were large for gestational age. With regard to transient CH, intrauterine growth retardation and preterm delivery were independent risk factors for this form of CH. CONCLUSION: This study showed that many risk factors contribute to the aetiology of CH. In particular, our results suggested a multifactorial origin of CH in which genetic and environmental factors play a role in the development of the disease.

Growth and adult height in atypical coeliac patients, with or without growth hormone deficiency.

OBJECTIVE: To evaluate the effect of a gluten-free diet on growth and adult height, when available, in coeliac children without gastrointestinal symptoms. PATIENTS AND METHODS: Sixty-one coeliac children without gastro-intestinal symptoms were included in the study. The age at diagnosis was 9.50 +/- 3.3 years. Thirty-eight had short stature at diagnosis (< 10th percentile) and 23 had normal stature. Thirty-seven reached adult height. RESULTS: After beginning the diet an increase in growth velocity was seen in 30 patients (responders) (20 with initial short stature), while in 31 patients (18 with short stature) there was no catch-up growth (non-responders). Bone age at diagnosis was significantly more delayed in the responders than in the non-responders. Target height was significantly higher in children with normal stature at diagnosis than those with short stature. Growth hormone (GH) deficiency was found and confirmed after 6-12 months of diet in 12 of the 38 patients (32%) with short stature. In the group of the 30 'short' patients who attained final height, target height was attained or improved in 12 patients (40%): in eight of the 16 (50%) responders and in four of the 14 (29%) non-responders; in eight (all responders) out of 22 (36%) without GH deficiency, and in four out of eight (50%) patients with GH deficiency treated with GH (all non-responders). CONCLUSIONS: In children in whom coeliac disease is diagnosed because of short stature, a gluten-free diet will be successful if at diagnosis there is a delay of bone age and in the first year of diet there is an evident catch-up growth. When this does not occur, i.e. in half of the patients (18 out of 38), it may be because of an associated and transient GH deficiency. In these patients a period of GH replacement therapy as well as a gluten-free diet may improve their final height.

SRD5A2 gene analysis in an Italian population of under-masculinized 46,XY subjects.

OBJECTIVE: The differential diagnosis of male under-masculinization, including a wide spectrum of phenotypes and a heterogeneous genetic basis, is crucial for the correct management of the patients. To characterize an Italian population of under-masculinized males, we performed the molecular analysis of the SRD5A2 gene (2p23), encoding the 5alpha-reductase-2 enzyme that converts testosterone (T) to dihydrotestosterone (DHT), and is required for full masculinization of the male foetus. DESIGN AND PATIENTS: Twenty-six Italian patients with 46,XY kariotype and various degrees of ambiguous genitalia were retrospectively selected for this study. Twelve of these patients, 10 of whom were referred for partial androgen insensitivity syndrome (PAIS), were raised as females; 15 were raised as males and all had a severe hypospadias. For most of the patients, the case histories and hormonal findings were incomplete but all could be included in the clinical characteristics of under-masculinization. MEASUREMENT: For hormonal evaluation, T and DHT were measured by means of radioimmunoassay (RIA) and high-performance liquid chromatography (HPLC)-RIA methods, respectively. Genomic DNA of all patients and relatives was extracted from peripheral blood, the five exons of the SRD5A2 gene were amplified by polymerase chain reaction (PCR) and submitted to automatic sequencing. RESULTS: Five known mutations affecting the NADPH binding function and one new mutation affecting the enzyme C-terminus were identified in a total of eight patients (two of whom were sisters). Five families were characterized, and in two patients only one affected allele was observed. The extension of the analysis to the regions flanking exons allowed the identification of a new polymorphism in intron 2, whose frequency was determined. CONCLUSION: This first report of an Italian population underlines the importance of differential diagnoses in patients with under-masculinization. The lack of precise genotype-phenotype correlation in some of the mutations highlights the necessity to improve knowledge about the biochemical aspects of steroid 5alpha-reductase action and about the interactions of genetic and environmental factors.

Gonadoblastoma in Turner syndrome and Y-chromosome-derived material.

The identification of Y-chromosome material is important in females with Ullrich-Turner syndrome (UTS) due to the risk of developing gonadoblastoma or other gonadal tumors. There is controversy regarding the frequency of the Y-chromosome-derived material and the occurrence of gonadoblastoma in these patients. The aim of our study was to evaluate a large number of patients with UTS, followed before and during the pubertal age for the prevalence of Y-chromosome derived material, the occurrence of gonadoblastoma, and the incidence of possible neoplastic degeneration. An unselected series of 171 patients with UTS (1-34 years old), diagnosed cytogenetically, was studied for Y-chromosome markers (SRY and Y-centromeric DYZ3 repeats). The follow-up was of 2-22 years; 101 of these patients were followed during pubertal age. Y-chromosome material was found in 14 patients (8%): 12 of these were gonadectomized (2.8-25.9 years). A gonadoblastoma was detected in four patients under 16 years of age: in two, Y-material was detected only at molecular analysis (at conventional cytogenetic analysis, one was included in the 45,X group and one in the X + mar group) and one had also an immature teratoma and an endodermal sinus carcinoma. The prevalence of gonadoblastoma in our series of gonadectomized UTS patients with Y-positive material was of 33.3% (4/12). Our data suggest that the age of appearance and the possibility of malignant degeneration of gonadoblastoma can occur early in life. These patients, in particular those with 45,X or a marker chromosome may benefit from molecular screening to detect the presence of Y-chromosome material; PCR is a rapid and inexpensive technique. At the moment, laparoscopy and preventive gonadectomy performed as soon as possible remain the procedures of choice for patients with UTS, when Y-chromosome has been identified, as we are still unable to predict a future malignant evolution of gonadoblastoma.

Active and total ghrelin concentrations in the newborn.

BACKGROUND: Ghrelin is a peptide with a potent capacity to release GH and other metabolic activities. An acyl modification is indispensable for biological activity. Acylated and desacylated forms of ghrelin are both present in the blood. No data exist about the ratio between active ghrelin and total ghrelin in the first period of life. OBJECTIVE: To investigate whether ghrelin may be involved in physiological roles during fetal life. INFANTS AND METHODS: Ghrelin, growth hormone (GH), and leptin concentrations were measured in cord plasma in 98 newborns of healthy mothers. Acyl-ghrelin and the sum of acylated and desacylated forms of ghrelin (total ghrelin) were measured using specific radioimmunoassays. RESULTS: Acylated ghrelin and total ghrelin did not correlate with birth weight, gestational age, body mass index, head circumference, birth length, leptin or GH in plasma cord blood. CONCLUSIONS: The absence of clinically significant correlations between both active and total ghrelin and GH, leptin or anthropometric data does not enable us to ascribe a precise role to ghrelin in prenatal life.

Lung function in children with diabetes mellitus.

A cross-sectional study design was undertaken to assess pulmonary function in children with insulin-dependent diabetes mellitus (IDDM), and to establish if there is any relationship with diabetic factors and complications. Thirty-eight children (10 +/- 1.8 years) with IDDM and without clinical or radiological evidence of lung involvement, and 41 healthy age-matched reference subjects, underwent a pulmonary function study. Thirteen (34%) of 38 subjects with IDDM were studied at the onset of their disease. Adjusted values expressed as SD score of forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV(1)), and the transfer factor for carbon monoxide (TLCO) were found to be significantly lower than in controls (-0.54 +/- 0.87 vs. 0.40 +/- 1.10, P = 0.0008; -0.11 +/- 0.96 vs. 0.52 +/- 1.07, P = 0.01; -1.60 +/- 1.07 vs. -0.57 +/- 1.28, P = 0.001, respectively). These differences also existed in the group investigated at onset of diabetes. Residual volume (RV) and RV/total lung capacity ratio (RV/TLC) were significantly higher in the whole group of patients with IDDM than in controls (-0.20 +/- 0.83 vs. -0.80 +/- 0.88, P = 0.003; and 26 +/- 6.2 vs. 21 +/- 5.0, P = 0.0002, respectively). Seventeen patients (45%) had abnormal pulmonary function (SD score, less than -1.64): 16 subjects had reduced TLCO, 4 had reduced FVC, and in 3 of the 17, both functional indices were abnormal. There was no significant relationship between pulmonary function indices and diabetic factors or complications. The only significant association was between abnormal TLCO and females (P = 0.03), suggesting that sex may be a predisposing factor for the development of pulmonary complications. This study supports the view that the lung is functionally involved in children with IDDM early on in the course of the disease.

CYP21 genotype, adult height, and pubertal development in 55 patients treated for 21-hydroxylase deficiency.

In a retrospective study we evaluated long-term growth, pubertal developmental patterns to final height (FH), and medication in 55 patients (35 females) affected by 21-hydroxylase deficiency. The patients were classified into 3 groups according to predicted mutation severity: group A (11 women and 9 men), homozygous or compound heterozygous for null or In2 splice mutations [residual enzymatic activity (RA), <1%]; group B (11 women and 4 men), homozygous for I172N or R341P or R426H mutations (RA, approximately 2-3%) or compound heterozygous with any of the group A or B mutations; and group C (13 women and 7 men), homozygous for P30L or V281L or P453S mutations (RA, >30%) or compound heterozygous with any of the group A, B, or C mutations. Three patients showed unclassifiable genotypes. FH was similar in the female groups, whereas male patients in group B were shorter than males in groups A and C. Fifty-five percent of patients in group A, 33% in group B, and 40% in group C reached an FH within 0.5 SD of target height. Four of the 7 patients diagnosed via neonatal screening achieved an FH equal to or above the target height. In the entire group, early diagnosis (<1 yr) improved height outcome. Early diagnosed CAH patients who received lower cortisol equivalent doses during the first year of life reached a better FH. Our results underline the importance of mineralocorticoid therapy, as CAH subjects in groups A and B who did not receive this treatment showed reduced FH. Early diagnosis, the use of more physiological cortisol equivalent dosages during the first year of life, and the extension of mineralocorticoid therapy to all classical patients are shown to improve the auxological outcome. Genotypic analysis helped to interpret the height results of our cases and prospectively may represent a useful tool for improving the therapeutic choice and the height outcome.

The severity of clinical presentation of type 1 diabetes in children does not significantly influence the pattern of residual beta-cell function and long-term metabolic control.

AIM: The purpose of the present study was to compare relationships between the clinical presentation of type 1 diabetes in children and residual beta-cell secretion and long-term metabolic control. METHODS: This retrospective study was conducted in 66 diabetic children with age at diagnosis ranging from 0.7 to 14.8 yr. The patients showed contrasting characteristics at diagnosis: either diabetic ketoacidosis (DKA) (group 1, n = 29) or absence of metabolic derangement (group 2, n = 37) associated with marked (group 2A, n = 12) or mild hyperglycemia (group 2B, n = 25). A regular follow-up was available for at least 10 yr (10-32 yr) in all cases and for 20 yr in 23 cases. C-peptide levels were measured from diagnosis and thereafter at intervals for the first years of disease until becoming permanently undetectable. RESULTS: C-peptide levels at diagnosis were undetectable in about 20% of the cases both with and without DKA. C-peptide levels at diagnosis, the duration of measurable C-peptide levels and the maximum value found during follow-up were not significantly different in the three groups and were not correlated with glycated hemoglobin (GHb) calculated throughout the whole period. No differences were found between the groups of patients concerning GHb values and insulin dose at 10, 15 and 20 yr of disease. The patients of group 2A, characterized by an extremely high glycemic level without ketoacidosis, had a significantly higher prevalence of HLA DR3/4 heterozygosity. CONCLUSIONS: The severity of clinical presentation at diagnosis does not significantly influence residual beta-cell function, and long-term metabolic control.

Selecting girls with precocious puberty for brain imaging: validation of European evidence-based diagnosis rule.

OBJECTIVES: To test the sensitivities of recently published American recommendations predicting occult intracranial lesion (OICL) in girls with central precocious puberty (CPP), and to validate a previously derived diagnosis rule predicting OICL based on age at puberty onset and estradiol (E2) level. STUDY DESIGN: A retrospective, multicenter, hospital-based, cohort study was performed, including all girls with CPP seen in 7 centers in 6 European countries during given periods. American recommendations and the previously derived diagnosis rule were tested. RESULTS: Girls with CPP (n=443), including 35 with OICL, were recruited. American recommendations did not identify all OICL. Previously identified independent risk factors for OICL were confirmed: age <6 years (adjusted odds ratio 20.5; 95% CI, 8.1-52.1) and E2 >45th percentile (3.0; 95% CI, 1.3-7.1). The previously derived diagnosis rule had 100% sensitivity (95% CI, 90-100): all girls with OICL had either an age <6 years or an E2 level >45th percentile. The specificity was 39% (95% CI, 34-44). CONCLUSIONS: American recommendations do not seem safe to select European girls with CPP who require brain imaging. In settings where systematic brain imaging is not possible, the proposed diagnosis rule could safely help to avoid more than one third of unnecessary brain imaging.

Treatment for congenital hypothyroidism: thyroxine alone or thyroxine plus triiodothyronine?

OBJECTIVE: To compare the effects of therapy with thyroxine (T4) plus triiodothyronine (T3) versus T4 alone from the first days of life in screened congenital hypothyroid (CH) infants. METHODS: We examined 14 CH infants diagnosed by neonatal screening and a group of control infants. CH patients were divided randomly into 2 groups, 1 treated with T4 alone (group 1) and the other treated with T4 plus T3 (liothyronine; group 2). In all patients electrocardiography and thyroid hormone evaluations were performed before and 15 and 30 days and 3, 6, and 12 months after the beginning of therapy. Psychological tests were also performed at 6 and 12 months of age in CH patients and in other matched controls. RESULTS: After 15 days of treatment, serum thyrotropin (TSH) levels become normal in 5 of 7 cases of group 1 (median TSH level 10.7 micro U/ml) and in 1 of 7 cases of group 2 (median TSH level 72.5 micro U/ml). At the same period, serum-free thyroid hormone levels were within the normal range in both groups, but free T4 values were significantly higher in group 1 than in group 2 and in controls. At the subsequent examinations, free T4 values were within the upper normal limit in group 1, whereas they remained within the normal range in group 2. No clinical or electrocardiographic signs of heart disease were found in any of the patients. The psychometric quotient in CH infants was significantly lower than in controls, but similar in patients of group 1 and group 2. CONCLUSIONS: The combined treatment with T4 plus T3 seems not to show significant advantages, at least in our experimental conditions, compared with the traditional treatment with T4 alone in early treated CH infants. A further longer and more extensive follow-up is mandatory.

Noonan-like syndrome with loose anagen hair: a new syndrome?

We present three children with short stature, the same facial phenotype, macrocephaly, enlarged cerebral spinal fluid spaces, short neck with redundant skin, severe GH deficiency, mild psychomotor delay with attention deficit/hyperactivity disorder (ADHD), mild dilatation of the pulmonary root in two of them, and a unique combination of ectodermal abnormalities. Their appearance, not completely typical of Noonan syndrome, the behavioral phenotype, GH deficiency, darkly pigmented and hairless skin, and the unusual aspect of the hair, defined as loose anagen hair syndrome did not fit any known condition. We postulate that these children may represent a distinct, previously unreported syndrome that we would name "Noonan-like syndrome with loose anagen hair".

Low birth weight for gestational age and subsequent male gonadal function.

OBJECTIVE: To verify whether a reduced birth weight for gestational age was associated with a testicular dysfunction in postpubertal boys. STUDY DESIGN: Boys born small for gestational age (SGA) (n = 25) were compared to 24 born with an appropriate weight. All subjects were postpubertal (mean age 17.5 +/- 1.3 and 17.6 +/- 2.0 years, respectively). The following clinical and endocrinologic variables were evaluated: final height, target height, body mass index, testicular volume, follicle-stimulating hormone, luteinizing hormone, testosterone, and inhibin B. RESULTS: The SGA group had reduced testicular size (16.3 +/- 2.7 mL vs 22.8 +/- 3.2 mL; P <.0001) with a lower testosterone level (3.76 +/- 1.35 ng/mL vs 4.77 +/- 1.55 ng/mL; P <.05) and a higher LH value (4.41 +/- 1.61 IU/L vs 3.44 +/- 1.29 IU/L; P <.05). Among the SGA group, 54% had a mean testicular volume >2 SD below the control mean (ie, <16 mL) and in these subjects, the inhibin B level was low (143 +/- 46 pg/mL vs 229 +/- 76 pg/mL; P <.0001). SGA patients with smaller testes had lower final height relative to target height(P <.05 vs patients with larger testes) and for the SGA group, inhibin B correlated with testicular size (P <.0001). Positive correlations also were found between the reduction of final height relative to target height and testicular volume (P <.005) and inhibin B values (P <.05). CONCLUSIONS: SGA subjects have pituitary-gonadal axis function that tends toward hypogonadism. There is a disruption of the exocrine function in subjects with smaller testicular size who failed to show a complete height catch-up growth. This study supports a link between low birth weight and lower fertility in adult males.

The glucose area under the profiles obtained with continuous glucose monitoring system relationships with HbA(lc) in pediatric type 1 diabetic patients.

OBJECTIVE: The purpose of this study was to determine whether the continuous glucose monitoring system (CGMS) (MiniMed, Sylmar, CA) 1) is sufficiently representative of the overall metabolic control as assessed by HbA(1c), 2) could be used to identify a particular blood glucose threshold value affecting hemoglobin glycation; and 3) is able to show any relationship between particular glycemic profiles and HbA(1c) levels. RESEARCH DESIGN AND METHODS: Of 44 pediatric patients with type 1 diabetes who wore CGMS devices, 28 subjects were selected for the study. Criteria for inclusion were high levels of HbA(1c) (> or =8%) for more than 1 year or a history of frequent hypoglycemic episodes and a complete CGMS registration for 72 h. Age of the subjects ranged from 5.7 to 24.8 years, the mean duration of disease was 7.63 +/- 4.75 years, and the mean HbA(1c) value was 8.7 +/- 1.3%. CGMS data were downloaded and glucose profiles were analyzed. The area under each glucose profile was calculated by means of a professional digital planimeter. RESULTS: The glucose profiles showed a high frequency of prolonged hyperglycemic periods (80% of subjects) and a low frequency of postmeal glycemic peaks (29% of subjects). Postlunch values were significantly correlated with HbA(1c) levels, but the correlation disappeared when controlling for glucose area values. Glucose area values significantly correlated with HbA(1c) levels both when considered as a whole (40-400 mg/dl; r = 0.53, P = 0.002) and when considered fractioned (40-150, 40-200, 40-250, 40-300 mg/dl), apart from the 40-90 mg/dl partial area. HbA(1c) levels were significantly decreased 3 and 6 months after use of CGMS (P = 0.05 and 0.03, respectively, paired Student's t test). CONCLUSIONS: HbA(1c) levels may be decreased by using the information obtained with the CGMS. Three-day glucose profiles are representative of the overall glucose control, because glucose area values correlate with HbA(1c) levels. The only glucose threshold below which there seems to be no correlation with HbA(1c) is 90 mg/dl. Only glucose area, and not postprandial glucose values, are directly and independently correlated with HbA(1c). Therefore, to improve metabolic control, it is necessary to lower the whole mean 24-h glycemia and not just the postprandial glucose values.

Inhibin B levels in adolescents and young adults with type 1 diabetes.

OBJECTIVE/METHODS: To assess exocrine and endocrine testicular function in subjects with diabetes, we evaluated serum inhibin B, gonadotrophins and testosterone levels in 33 male adolescent and young adult patients affected by type-1 diabetes (age 21.0 +/- 5 years; range 14.2-33.3), with a mean disease duration of 12.7 +/- 5.8 years (range 1.5-25.3) and various metabolic control (HbA1c 7.8 +/- 1.5%; range 5.5-13.2) and compared them with those of an age-matched group of 36 healthy control subjects (age 19.5 +/- 4.1 years; range 13.6-28.1). Both patients and controls had a testicular volume >or=15 ml. Inhibin B was measured by ELISA method. RESULTS/CONCLUSION: Diabetics and controls had comparable inhibin B (203 +/- 74 vs. 221 +/- 69 pg/ml, respectively) and follicle-stimulating hormone (FSH) levels, while luteinizing hormone (LH) and testosterone levels were significantly higher in the diabetic group. Inhibin B was negatively correlated both in patients and controls with FSH, while a negative correlation with LH was found only in the diabetic group. We conclude that our young diabetic males, after a mean disease duration of 12 years and various metabolic control, had inhibin B and FSH levels comparable to those of normal subjects. Therefore, they seem to have a regular testicular function and in particular a normal seminiferous tubule/Sertoli cell activity despite sustained hyperglycemia.

Enhanced activity of the plasma membrane oxidoreductase in circulating lymphocytes from insulin-dependent diabetes mellitus patients.

Circulating human lymphocytes contain a transmembrane oxidoreductase (PMOR) capable of reducing dichlorophenol indophenol (DCIP) by endogenous reductants, presumably NADH. Membranes from lymphocytes obtained from buffy coats contain a NADH DCIP reductase having a K(m) of about 1 microM and almost insensible to dicoumarol. The PMOR of lymphocytes from insulin-dependent diabetic patients is higher than that from age-matched controls and, in addition, has a dicoumarol-sensitive component, lacking in most controls, presumably due to membrane association of DT-diaphorase. The increase of PMOR in diabetes is likely due to overexpression of the enzyme, in view of the very low K(m) for NADH indicating that, in intact cells, the enzyme is practically saturated with the reductant substrate.