Changes in lifestyle improve body composition, thyroid function, and structure in obese children.

BACKGROUND: Alterations in thyroid function and structure have been reported in obesity. Function reverses to normal after weight loss, but nothing is known about structure. AIM: To evaluate the effect of weight loss on thyroid function and structure in obese children. SUBJECTS AND METHODS: The study was conducted in 72 overweight and obese children. Measurement of free T(3) (fT(3)), free T4 (fT(4)), TSH, antithyroid- antibodies and a thyroid ultrasound was performed at the beginning (phase 1) and after a period of 1.8±1.0 yr of lifestyle intervention (phase 2). RESULTS: Height SD score (SDS), body mass index SDS, total fat mass did not change from phase 1 to phase 2. Percentage of fat free mass decreased significantly (p<0.05). Waist/height ratio decreased (0.6±0.1 vs 0.5±0.1; p<0.05) as well as waist/hip ratio (0.9±0.1 vs 0.8±0.1; p<0.05). In phase 1, TSH was 2.8±1.7 mU/l; in phase 2, it was 2.2±0.9 mU/l (p<0.05); 17.2% of children showed a TSH level above the normal range (3.6 mU/l) in phase 1, and 6.2% in phase 2 (p<0.05). fT(4) was 10.8±2.2 pg/ml in phase 1 and 10.7±1.9 pg/ml in phase 2. fT(3) was 4.4±1.3 pg/ml (phase 1) and 3.9±1.1 pg/ml (phase 2) (p<0.05). Thyroid volume was -0.5±0.8 SDS (phase 1) and -0.5±1 SDS (phase 2). A non-significant improvement in thyroid structure was observed. CONCLUSIONS: In conclusion, healthier lifestyle improves body composition, thyroid function, and structure.

GH secretion in a cohort of children with pseudohypoparathyroidism type Ia.

Pseudohypoparathyroidism type Ia (PHP-Ia) is characterized by Albright's hereditary osteodistrophy (AHO) and resistance to hormones that act via the alpha subunit of the Gs protein (Gsalpha) protein, ie PTH, TSH, FSH/LH, and, as recently described in limited series, GHRH. However, the current lack of data on GHRH secretion, obesity and short stature included in the AHO phenotype hampers interpretation of GH secretory status and its effects on these subjects. We evaluated GH secretion after GHRH plus arginine (Arg) stimulus, IGF-I levels and anthropometric features in an exclusively pediatric population of 10 PHP-Ia subjects. Of our PHP-Ia children, 5 out of 10 (50%) showed impaired GH responsiveness to the provocative test, with a lower prevalence than the 75-100% previously reported. A negative correlation (p=0.024) was found between GH secretion and body mass index (BMI), whereas no correlation emerged between GH and IGF-I values (p=0.948). Height and growth velocity did not significantly differ between GH-deficient and GH-sufficient subjects. In the 5 GH-deficient patients, GHRH resistance could arguably be responsible for hormonal impairment; however, 3 of them were obese, showing normal stature and IGF-I levels: the increased BMI in these subjects could influence GH secretion and its effects. In conclusion, GH deficiency is frequent among PHP-Ia children and its prevalence is variable, two factors indicating that GH secretory testing should be part of the routine management of this patient group. It could be argued that GHRH resistance is the pathogenetic mechanism in most patients, but further studies on GHRH secretion are needed to define which values can be considered as raised. Lastly, because BMI has been indicated as a major determinant of evoked adult GH response to provocative testing, GH levels related to increased BMI also in childhood could be helpful in defining GH assessment in obese or overweight PHP-Ia children.

Common polymorphisms of the growth hormone (GH) receptor do not correlate with the growth response to exogenous recombinant human GH in GH-deficient children.

CONTEXT: GH acts through the GH receptor (GHR), whose polymorphisms might affect the growth response to recombinant human GH (rhGH). OBJECTIVE: The objective of this study was to investigate possible influences of GHR polymorphisms on the growth response to rhGH in GH-deficient (GHD) children. DESIGN: This was a 2-yr study (first year, spontaneous growth; second year, growth during rhGH treatment). SETTING: This study was performed at a referral center. PATIENTS: Fifty-four prepubertal GHD children (11 females; mean age, 7.8 yr; sd, 3.96) were studied. INTERVENTION: Patients were treated with rhGH (0.2 mg/kg.wk) for at least 1 yr after diagnosis. Growth velocity (GV) was measured 1 yr before treatment and during the first treatment year. GHR exons were amplified by PCR using pairs of intronic primers. The presence of single or multiple mismatches in the PCR products was revealed by denaturing high-pressure liquid chromatography. For exons in which mismatches were found by denaturing high-pressure liquid chromatography, direct sequencing was performed by automatic sequencer. MAIN OUTCOME MEASURES: Before the start of treatment, the mean height (Ht) sd score was -1.93 (sd, 0.70), and the mean GV sd score was -1.49 (sd, 1.26). RESULTS: The posttreatment (first 12 months) mean GV sd score was 3.55 (sd, 3.27). Molecular analysis revealed a high frequency of GHR polymorphisms; in particular: exon 3 deletion (Del 3) in 26 subjects (48%), polymorphism 504 A>G at codon 168 of exon 6 in 44 (82%), and polymorphism 1576 A>C at codon 526 of exon 10 in 35 (65%). In most patients, these different polymorphisms recurred in association. We found no significant differences in GV between the groups of subjects defined by the polymorphic genotypes. CONCLUSION: The most common GHR polymorphisms, alone or in association, do not appear to affect the growth response to rhGH in GHD children.

Geometry and bone density.

Bone development is a key process in the growing child. It is, therefore, of paramount importance to survey this process, which is characterized by increasing length and size of the bone together with its progressive mineralization. The bone status can be evaluated by different techniques, each of them having its pros and cons. Furthermore, it should be underlined that the results of bone assessment depend not only from the employed technique but also from the auxological characteristics of the subjects. It is, therefore, the aim of this review to examine the characteristics of the various methods of bone evaluation, such as dual energy X-ray absorptiometry (DEXA), peripheral quantitative computed tomography (pQCT), ultrasound and metacarpal index and to explain how changes in bone structure and geometry may influence the results.

Overnight growth hormone secretion in short children: independence of the sleep pattern.

PURPOSE: to analyze the interrelationships between GH secretion and pattern of sleep. PATIENTS: 18 children (10 male, 8 female; mean age 9.1 yr, range 5.1-14.3 yr), with short stature (mean height standard deviation score (SDS) -2.52, range -3.86-(-)1.88; mean height velocity SDS -1.1, range -2.40-(-)0.08), including 9 children with genetic short stature and 9 with idiopathic short stature. METHODS: blood samples were taken every 15 min from 2000 h-0800 h, and GH profiles were analyzed by the PULSAR computerized peak identification algorithm; simultaneous sleep was analyzed by electroencephalogram recording. RESULTS: no significant correlation was noted between GH secretion parameters and any of the electroencephalogram parameters evaluated: stage 1 (S1) percent, stage 2 (S2) percent, slow-wave sleep (SWS) percent, rapid eye movement sleep percent, wakefulness (W) percent, and sleep efficiency (EFF); there was no significant difference in GH secretion between children with EFF less than 76% and those with EFF more than 76% (P > 0.5). Maximal GH peak coincided 9 times (50%) with SWS, 3 times (17%) with S2, 3 times with W, twice (11%) with S1, and once (6%) with rapid eye movement sleep. First GH peak coincided 12 times (67%) with W, 3 times with S2, twice with SWS, and once with S1. There was no significant difference comparing the percentage of sleep stages occurring in the 15 min of maximal GH increment, in the 15 min preceding it, and in those following it; there was no significant difference comparing the percentage of sleep stages occurring in the 15 min preceding the onset of a GH peak and in those following it. CONCLUSIONS: GH secretion in short children seems independent of the sleep stage and efficiency; in children it is possible that GH secretion relates with sleep per se and with neurohormonal changes occurring at nighttime rather than with a specific sleep stage or sleep stage sequence.

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy syndrome: time to review diagnostic criteria?

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is an autosomal-recessive syndrome defined by two of the following conditions: chronic mucocutaneous candidiasis, hypoparathyroidism, or Addison's disease. Other autoimmune conditions may be associated, such as hypothyroidism, hypogonadism, insulin-dependent diabetes mellitus, chronic active hepatitis, pernicious anemia, vitiligo, alopecia, biliary cirrhosis, and ectodermal dysplasia. APECED is caused by mutations in the autoimmune regulator gene, mapping to 21q22.3. We report on three patients whose clinical and molecular features challenge the currently used diagnostic criteria for APECED. AR presented at 15 yr of age with a history of recurrent infections and mucocutaneous candidiasis. He is now 21 yr old, and no other signs or symptoms of APECED have appeared to date. DR presented at 7 yr of age with hypocalcemia and a prolonged Q-T interval on the electrocardiogram. He also had minor facial dysmorphisms and mild mental retardation. Serum calcium levels were low, PTH levels were undetectable, and hypoparathyroidism was therefore diagnosed. All other biochemical, immunological, and endocrinological tests were normal. DR is now 8 yr old with no other signs or symptoms of APECED. ST presented at 14 yr of age for alopecia aerata and pitted nail dystrophy and goiter. Thyroid function was normal in the presence of thyroid-specific antibodies. No other signs or symptoms of APECED have appeared to date. Genetic analysis revealed a typical mutation (R257X) on a single allele in both AP and DR; in ST, heterozygosity for a novel mutation (V484M) involving one of the zinc fingers of the plant homeodomain of the protein was found. The finding of a typical APECED mutation in two patients presenting with one isolated major clinical APECED feature and of a novel mutation in a patient presenting with atypical features of APECED onset suggests that the time might have come for updating the diagnostic criteria of this syndrome.

Prenatal diagnosis of thyroid hormone resistance.

A 29-yr-old woman with pituitary resistance to thyroid hormones (PRTH) was found to harbor a novel point mutation (T337A) on exon 9 of the thyroid hormone receptor beta (TRbeta) gene. She presented with symptoms and signs of hyperthyroidism and was successfully treated with 3,5,3'-triiodothyroacetic acid (TRIAC) until the onset of pregnancy. This therapy was then discontinued in order to prevent TRIAC, a compound that crosses the placental barrier, from exerting adverse effects on normal fetal development. However, as the patient showed a recurrence of thyrotoxic features after TRIAC withdrawal, we sought to verify, by means of genetic analysis and hormone measurements, whether the fetus was also affected by RTH, in order to rapidly reinstitute TRIAC therapy, which could potentially be beneficial to both the mother and fetus. At 17 weeks gestation, fetal DNA was extracted from chorionic villi and was used as a template for PCR and restriction analysis together with direct sequencing of the TRbeta gene. The results indicated that the fetus was also heterozygous for the T337A mutation. Accordingly, TRIAC treatment at a dose of 2.1 mg/day was restarted at 20 weeks gestation. The mother rapidly became euthyroid, and the fetus grew normally up to 24 weeks gestation. At 29 weeks gestation mild growth retardation and fetal goiter were observed, prompting cordocentesis. Circulating fetal TSH was very high (287 mU/L) with a markedly reduced TSH bioactivity (B/I: 1.1 +/- 0.4 vs 12.7 +/- 1.2), while fetal FT4 concentrations were normal (8.7 pmol/L; normal values in age-matched fetuses: 5-22 pmol/L). Fetal FT3 levels were raised (7.1 pmol/L; normal values in age-matched fetuses: <4 pmol/L), as a consequence of 100% cross-reactivity of TRIAC in the FT3 assay method. To reduce the extremely high circulating TSH levels and fetal goiter, the dose of TRIAC was increased to 3.5 mg/day. To monitor the possible intrauterine hypothyroidism, another cordocentesis was performed at 33 weeks gestation, showing that TSH levels were reduced by 50% (from 287 to 144 mU/L). Furthermore, a simultaneous ultrasound examination revealed a clear reduction in fetal goiter. After this latter cordocentesis, acute complications occured, prompting delivery by cesarean section. The female neonate was critically ill, with multiple-organ failure and respiratory distress syndrome. In addition, a small goiter and biochemical features ofhypothyroidism were noted transiently and probably related to the prematurity of the infant. At present, the baby is clinically euthyroid, without goiter, and only exhibits biochemical features of RTH. In summary, although further fetal studies in cases of RTH are necessary to determine whether elevated TSH levels with a markedly reduced bioactivity are a common finding, our data suggest transient biochemical hypothyroidism in RTH during fetal development. Furthermore, we advocate prenatal diagnosis of RTH and adequate treatment of the disease in case of maternal hyperthyroidism, to avoid fetal thyrotrope hyperplasia, reduce fetal goiter, and maintain maternal euthyroidism during pregnancy.

A four year dose-response study of recombinant human growth hormone treatment of growth hormone deficient children: effects on growth, bone growth and bone mineralization.

To evaluate the effects of two regimens of recombinant human GH (rhGH) on growth, bone growth and bone mineralization in GH deficient children, we studied two groups (A and B), each including 16 GH deficient children matched for sex, age, body mass index, height, height velocity and bone age/chronological age ratio (BA/CA). Group A was treated with a weekly rhGH dose of 1IU/kg and group B with 0.5IU/kg. After four years of therapy, we evaluated the auxological outcome, bone morphometry (metacarpal index: MI) and bone mineralization by quantitative roentgen microdensitometry at the middle region of the II metacarpal and ultra-distal radius. Height increased significantly in both groups, being significantly higher in group A after four years of therapy, while BA/CA remained similar in the two groups. Bone growth (measured by the MI), and bone mineral density at the metacarpal (mostly trabecular bone) and at the ultra-distal radial (mostly cortical bone) site did not differ in the two groups, nor did these three parameters differ from normal controls. In conclusion, after four years a greater height gain was achieved by the higher dose of rhGH compared with the conventional dose, but there were no differences in bone growth and mineralization.

Pseudohypoaldosteronism: report of a case presenting as failure to thrive.

We report a 2 month-old infant referred for failure to thrive. At birth, weight was 3820 g and length 52 cm. After physiologic weight loss, the patient showed no further weight gain for the next two months. On admittance (age 2 mo), weight was 3340 g and length 53 cm; the infant had severe dystrophy, generalized hypotonia and dehydration; blood chemistry showed hyponatremia, hyperkalemia and hypochloremia. A salt losing syndrome of adrenal origin was hypothesized. However, rehydration and hydrocortisone administration failed to correct hyponatremia and hyperkalemia. Endocrine assessment showed high levels of aldosterone and plasma renin activity, suggesting pseudohypoaldosteronism. Oral sodium chloride supplementation normalized electrolyte balance and the patient showed progressive weight gain and catch-up growth, confirming the diagnosis.

Idiopathic short stature.

Idiopathic short stature (ISS) is a term used to describe the status of children with short stature that cannot be attributed to a specific cause. Many children diagnosed as having ISS have partial GH insensitivity, which can result from disturbances at various points of the GH-IGF-I axis. Several clinical studies on spontaneous growth in ISS showed that adult height was almost in the range of target height. GH treatment led to adult height not significantly higher than the pretreatment predicted adult height in most reports. No metabolic side effects have been observed, even when the dose was higher than in GH deficiency. Manipulation of puberty with gonadotrophin releasing hormone analogues reported by a few authors in a small number of children has shown conflicting results. Long-term psychological benefits of GH therapy for short normal children have not been demonstrated to date.

Optimal therapy of pubertal disorders in precocious/early puberty.

GnRHa have been used in the treatment of central precocious puberty (CPP) for a decade and some final results of this therapy are now available. Treatment preserves height potential in younger patients and a complete recovery of the hypothalamic-pituitary-gonadal axis occurs at the end of treatment. However, some aspects of the management of CPP are still debated. Probably the age limits between normal and precocious puberty have to be lowered, and new diagnostic tools will modify and simplify diagnostic criteria. The possibility of progression of premature thelarche into precocious puberty, the pathogenesis of organic and idiopathic precocious puberty, the criteria for decision to treat and to stop treatment and the utility of an association with GH treatment will be better understood in the future. Follow-up of patients after stopping therapy includes frequency and characteristics of menses, the possible higher incidence of polycystic ovary-like syndrome and the correct achievement of a normal peak bone mass and body composition. In this review we discuss some of these points, with particular attention to precocious puberty in girls.

McCune-Albright syndrome: a longitudinal clinical study of 32 patients.

We report the diagnostic clinical features and their long term evolution in 32 patients with McCune-Albright syndrome. Patient data are made up of two periods: the first, classified as personal history, is from birth until the time when the diagnosis of McCune-Albright syndrome was made; the second, classified as clinical observation, is from the first observation until the end of follow up. The total duration of these two periods was 9.6+/-2.9 yr; mean age at first observation was 5.7 yr (range 0.7-11 yr). The probability of manifesting main clinical signs according to age was calculated: almost all had skin dysplasia at birth, 50% probability of peripheral precocious puberty in females at 4 years and 50% of bone dysplasia at 8 years of age were found. Other clinical signs had diagnostic relevance when preceding the main signs leading to diagnosis of McCune-Albright syndrome even without specific genetic investigation. The most important clinical manifestations have different evolutions: skin lesions increase in dimensions according to body growth; precocious puberty in females evolves rapidly but periods of regression can be seen in some patients; bone dysplasia in most patients evolves with an increase both in the number of affected bones and in the severity of lesions.

Growth hormone/IGF-I axis and growth hormone receptor mutations in idiopathic short stature.

BACKGROUND/AIMS: It was hypothesized that some children with idiopathic short stature (ISS) may have partial insensitivity to growth hormone (GH). In this study analysis of the GH/IGF-I axis as well as GH receptor (GHR) gene was done in children with ISS to determine the possible underlying factor(s) to their short stature. METHODS: Forty-eight patients with a diagnosis of ISS were studied; 33 boys and 15 girls aged 13.6 ± 3.7 years. Molecular analysis of the GHR was performed and GH sensitivity was tested by the IGF-I generation test. RESULTS: Basal IGF-I levels were <-2 SD in 22.9%, and 53.5% showed an IGF-I response below 40% (0-38%) to GH stimulation. GH-binding protein (GHBP) levels were below the normative mean in almost all patients. Mutations in the region of the GHR gene that codes for the extracellular domain of the receptor were found in 15.5%; one newly described mutation was recorded. CONCLUSION: With the possible exception of the novel G62V mutation, functional studies of the other 2 heterozygous mutations found in 6 of our patients are needed in order to prove their impact on short stature.

Menstrual disorders in adolescence.

Altered frequency of the menstrual cycle accompanied by pain are manifestations of functional anomalies of the female reproductive system. These symptoms require prompt and accurate diagnosis and therapy to prevent a chronic condition that can seriously disturb the adolescent's psychic well being. The most common anomalies of the menstrual cycle and the causes of altered cycle frequency are outlined, as are useful criteria for diagnosing premenstrual syndrome dysmenorrhea and for distinguishing the causes and alterations in frequency and amount of menstrual discharge from other disturbances, including amenorrhea and abnormal uterine bleeding. The treatment of dysmenorrhea and quantitative alterations of the menstrual cycle is the focus of this article.

The effect of cyproterone acetate on the growth of children with central precocious puberty.

We have examined the growth and skeletal maturation of 19 children (6 male, 13 female) with central precocious puberty. The aetiology in nine patients (5 male, 4 female) was secondary to a hypothalamic hamartoma. Six children (2 male, 4 female) received no treatment whereas 13 children (4 male, 9 female) were treated with cyproterone acetate in a mean dose of 68 mg/m2 per day (range, 34-260) for a mean duration of 4.5 years (range, 0.8-7.9). There was no significant difference between height SDS for bone age at the beginning and end of observation in either treated or untreated groups. No significant relationship between the mean dose of cyproterone acetate used and change in height SDS for bone age could be determined. We conclude that cyproterone acetate has no beneficial effect on the growth prognosis of children with central precocious puberty.

Growth hormone (GH) isoforms following acute 22-kDa GH injection: is it useful to detect GH abuse?

The aim of the study was to investigate the influence of an acute administration of 22-kDa hGH (22-kDa GH) on 22-kDa GH and 20-kDa GH serum levels, biological activity of GH (Nb2-GH) and on 22-kDa/20-kDa GH ratio, in order to verify whether the assessment of the GH isoforms could be a potential tool for diagnosing GH abuse. Twenty-eight children (21 M, 7 F), age 10.4 +/- 0.8 y, affected by idiopathic isolated GH deficiency and 10 children (8 M, 2 F), age 9.2 +/- 2.3 y affected by constitutional growth delay, were evaluated. After an overnight fast, a basal blood sample was obtained between 8 a.m. and 9 a.m. and a dose of 22-kDa GH was then administered subcutaneously (0.1 U/Kg). Blood was drawn after 2, 4 and 6 h, for the evaluation of 22-kDa GH, Nb2-GH and 20-kDa GH serum levels. Similar results were obtained in patients and controls: a significant rise, although of variable amplitude, of 22-kDa GH and Nb2-GH was found (p < 0.001) and the maximum peak was detected after 4 h in the majority of subjects. No acute changes in 20-kDa GH serum levels were observed. The 22-kDa/20-kDa GH ratio increased progressively, due to the rising levels of 22-kDa GH. A positive correlation was seen between 22-kDa GH and Nb2-GH levels at baseline and at 2, 4 and 6 h (p < 0.014, r = 0.99). Since in normal subjects the ratio of endogenous 22-kDa GH and 20-kDa GH is constant, an altered ratio of 22-kDa/20-kDa GH is highly suggestive of GH abuse. The short period of time available for the evaluation however (within 3 h from GH injection), severely limits this investigational tool in athletes.