Genetics of Bone Mass in Childhood and Adolescence: Effects of Sex and Maturation Interactions

We aimed to determine if adult bone mineral density (BMD) susceptibility loci were associated with pediatric bone mass and density, and if sex and pubertal stage influenced any association. We analyzed prospective areal BMD (aBMD) and bone mineral content (BMC) data from the Bone Mineral Density in Childhood Study (n = 603, European ancestry, 54% female). Linear mixed models were used to assess if 77 single-nucleotide polymorphisms (SNPs) near known adult BMD susceptibility loci interacted with sex and pubertal stage to influence the aBMD/BMC; adjusting for age, BMI, physical activity, and dietary calcium. The strongest main association was observed between an SNP near C7orf58 and distal radius aBMD. However, this association had a significant sex • SNP interaction, revealing a significant association only in females (b = -0.32, p = 1.8 × 10(-6)). Furthermore, the C12orf23 locus had significant interactions with both sex and pubertal stage, revealing associations in females during Tanner stage I for total hip aBMD (b = 0.24, p = 0.001) and femoral neck aBMD (b = 0.27, p = 3.0 × 10(-5)). In contrast, the sex • SNP interactions for loci near LRP5 and WNT16 uncovered associations that were only in males for total body less head BMC (b = 0.22, p = 4.4 × 10(-4)) and distal radius aBMD (b = 0.27, p = 0.001), respectively. Furthermore, the LRP5 locus interacted with both sex and pubertal stage, demonstrating associations that were exclusively in males during Tanner V for total hip aBMD (b = 0.29, p = 0.003). In total, significant sex • SNP interactions were found at 15 loci; pubertal stage • SNP interactions at 23 loci and 19 loci interacted with both sex and pubertal stage. In conclusion, variants originally associated with adult BMD influence bone mass in children of European ancestry, highlighting the fact that many of these loci operate early in life. However, the direction and magnitude of associations for a large number of SNPs only became evident when accounting for sex and maturation.

BMD Loci Contribute to Ethnic and Developmental Differences in Skeletal Fragility across Populations: Assessment of Evolutionary Selection Pressures

Bone mineral density (BMD) is a highly heritable trait used both for the diagnosis of osteoporosis in adults and to assess bone health in children. Ethnic differences in BMD have been documented, with markedly higher levels in individuals of African descent, which partially explain disparity in osteoporosis risk across populations. To date, 63 independent genetic variants have been associated with BMD in adults of Northern-European ancestry. Here, we demonstrate that at least 61 of these variants are predictive of BMD early in life by studying their compound effect within two multiethnic pediatric cohorts. Furthermore, we show that within these cohorts and across populations worldwide the frequency of those alleles associated with increased BMD is systematically elevated in individuals of Sub-Saharan African ancestry. The amount of differentiation in the BMD genetic scores among Sub-Saharan and non-Sub-Saharan populations together with neutrality tests, suggest that these allelic differences are compatible with the hypothesis of selective pressures acting on the genetic determinants of BMD. These findings constitute an explorative contribution to the role of selection on ethnic BMD differences and likely a new example of polygenic adaptation acting on a human trait.

A trans-ethnic genome-wide association study identifies gender-specific loci influencing pediatric aBMD and BMC at the distal radius

Childhood fractures are common, with the forearm being the most common site. Genome-wide association studies (GWAS) have identified more than 60 loci associated with bone mineral density (BMD) in adults but less is known about genetic influences specific to bone in childhood. To identify novel genetic factors that influence pediatric bone strength at a common site for childhood fractures, we performed a sex-stratified trans-ethnic genome-wide association study of areal BMD (aBMD) and bone mineral content (BMC) Z-scores measured by dual energy X-ray absorptiometry at the one-third distal radius, in a cohort of 1399 children without clinical abnormalities in bone health. We tested signals with P < 5 × 10(-6) for replication in an independent, same-age cohort of 486 Caucasian children. Two loci yielded a genome-wide significant combined P-value: rs7797976 within CPED1 in females [P = 2.4 × 10(-11), β =- 0.30 standard deviations (SD) per T allele; aBMD-Z] and rs7035284 at 9p21.3 in males (P = 1.2 × 10(-8), β = 0.28 SD per G allele; BMC-Z). Signals at the CPED1-WNT16-FAM3C locus have been previously associated with BMD at other skeletal sites in adults and children. Our result at the distal radius underscores the importance of this locus at multiple skeletal sites. The 9p21.3 locus is within a gene desert, with the nearest gene flanking each side being MIR31HG and MTAP, neither of which has been implicated in BMD or BMC previously. These findings suggest that genetic determinants of childhood bone accretion at the radius, a skeletal site that is primarily cortical bone, exist and also differ by sex.

Gestational weight gain and obesity, adiposity and body size in African-American and Dominican children in the Bronx and Northern Manhattan

Gestational weight gain (GWG) is potentially modifiable and is associated with infant size and body composition; however, long-term effects on childhood obesity have not been reported among multi-ethnic urban populations. We examined the association between GWG and child anthropometric measures and body composition at 7 years [waist circumference (WC), body mass index z-score (BMIZ), obesity (BMIZ ≥95%ile) and bioelectrical impedance analysis estimates of percentage body fat (%fat)] in African-American and Dominican dyads (n = 323) in the Columbia Center for Children's Environmental Health prospective birth cohort study from 1998 to 2013. Linear and logistic regression evaluated associations between excessive GWG [>Institute of Medicine (IOM) 2009 guidelines] and outcomes, adjusting for pre-pregnancy BMI and covariates. Pre-pregnancy BMI (mean ± standard deviation, all such values) and total GWG were 25.8 ± 6.2 kg m(-2) (45% overweight/obese) and 16.4 ± 7.9 kg (64% > IOM guidelines), respectively. Excessive GWG was associated with higher BMIZ {0.44 [95% confidence interval (CI): 0.2, 0.7], P < 0.001}, WC [β: 2.9 cm (95% CI: 1.1, 4.6), P = 0.002], %fat at 7 years [β: 2.2% (95% CI: 1.0, 3.5), P = 0.001)] and obesity [odds ratio: 2.93 (95% CI: 1.5, 5.8), P = 0.002]. Pre-pregnancy BMI was positively associated with child size, adiposity and obesity (all P < 0.05). Excessive GWG was highly prevalent and was associated with child obesity, greater percentage body fat and abdominal adiposity. Strategies to support healthy GWG are warranted to promote healthy growth and prevent childhood obesity.

An update on childhood bone health: mineral accrual, assessment and treatment

PURPOSE OF REVIEW

To update the reader's knowledge about the factors that influence bone mineral accrual and to review the advances in the assessment of bone health and treatment of bone disorders.

RECENT FINDINGS

Maternal vitamin D status influences neonatal calcium levels, bone mineral density (BMD) and bone size. In turn, BMD z-score tends to track in childhood. These factors highlight the importance of bone health as early as fetal life. Dual-energy x-ray absorptiometry is the mainstay of clinical bone health assessment in this population because of the availability of appropriate reference data. Recently, more information has become available about the assessment and treatment of bone disease in chronically ill pediatric patients.

SUMMARY

Bone health must become a health focus starting prenatally in order to maximize peak bone mass and to prevent osteoporosis-related bone disease in adulthood. Vitamin D, calcium and weight-bearing activity are the factors of key importance throughout childhood in achieving optimal bone health as BMD z-score tracks through childhood and into adulthood. Recent updates of the International Society for Clinical Densitometry focus on the appropriate use of dual-energy x-ray absorptiometry in children of all ages, including children with chronic disease, and on the treatment of pediatric bone disease.

The Relationship of Metabolic Syndrome and Body Composition in Children with Premature Adrenarche: Is It Age Related?

BACKGROUND

Studies that evaluate both body composition and metabolic syndrome (MeS) risk in prepubertal children with premature adrenarche (PA) are limited.

METHODS

Fifty-eight prepubertal children (aged 5-9 years, 33 female and 25 male), 30 with PA and 28 controls, were evaluated for the presence of MeS as defined by age-modified National Cholesterol Education Program Adult Treatment Panel III criteria. A subset had dual-energy X-ray absorptiometry and bone markers (n = 23/58) to evaluate the effect of hyperandrogenism on metabolic abnormalities and body composition.

RESULTS

There was no difference in the prevalence of MeS between PA and controls (p = 0.138). Children with MeS were obese with an increased waist circumference (WC) and decreased high-density lipoprotein levels. Androgens were not associated with having more than one criterion for MeS (p = 0.08) but were associated with triglycerides and WC (p = 0.029 and p = 0.041, respectively). Lean mass was greater in PA subjects (p = 0.039), and androgens correlated with bone mineral density (p = 0.029) and total body fat (p = 0.008). Subjects with a higher percent of body fat were more likely to have more than one MeS risk factor (p = 0.005).

CONCLUSIONS

MeS was seen only in obese subjects whether or not they had PA. Thus, it appears that obesity drives metabolic risk in the prepubertal population rather than PA. Our findings are important in determining how the prepubertal patient with PA should be evaluated for metabolic risk.

Anti-Mullerian hormone may be a useful adjunct in the diagnosis of polycystic ovary syndrome in nonobese adolescents

OBJECTIVES

This study aimed to [1] confirm that nonobese adolescents with polycystic ovary syndrome (PCOS) have higher anti-Mullerian hormone (AMH) than controls; [2] examine the relationship of AMH with PCOS features and hormonal profile; and [3] approximate an AMH value that discriminates between adolescents with PCOS and controls.

DESIGN

Case-control study.

SETTING

Subspecialty ambulatory clinic.

PATIENTS

Thirty-one nonobese adolescent girls (age 13-21 years), 15 with PCOS diagnosed using the National Institutes of Health (NIH) criteria and 16 healthy control subjects. Subjects and controls were comparable for body mass index z-score, age and ethnicity.

MAIN OUTCOME MEASURE(S)

AMH in PCOS subjects and control groups, correlation of AMH with hormonal parameters.

RESULTS

AMH was higher in PCOS subjects (4.4±3.4 ng/mL) than in controls (2.4±1.3 ng/mL), when adjusted for menstrual age. In the entire group (PCOS and controls), AMH correlated with androgens, ovarian size and the presence of polycystic ovary (PCO) appearance. There was no difference in average ovarian size between PCOS (7.1±2.6 cm³) and controls (6.7±1.8 cm³). PCOS subjects were 1.49 times more likely to have AMH >3.4 ng/mL (confidence interval 0.98-2.26 ng/mL).

CONCLUSIONS

Our data suggest that AMH may be a useful adjunct in the diagnosis of PCOS in adolescents.

Outcome analysis of aromatase inhibitor therapy to increase adult height in males with predicted short adult stature and/or rapid pubertal progress: a retrospective chart review

BACKGROUND

Aromatase inhibitors (AIs) have been used off-label to increase adult height in short adolescent males. Studies have shown that AIs increase the predicted adult height (PAH) while delaying bone age (BA) maturation. We sought to determine whether AI therapy increases PAH in boys with short stature or rapid pubertal progression, and to evaluate any untoward effects.

METHODS

The charts of 27 boys with BA ≥ 13 and short stature [height ≥ 2 standard deviation (SD) below the mean or ≥ 2 SD below mid-parental target height (MPTH)] or rapid pubertal progress, treated with anastrozole were reviewed. Outcome measures included anthropomorphic, hormonal, and metabolic data.

RESULTS

The AI therapy averaged 21 months (range 14-30 months) for all, with Rx group 1 receiving <18 months therapy (n=7) and Rx group 2 receiving 18-30 months therapy (n=20). Post-therapy, in Rx group 1 and all subjects, there was no significant change in the PAH, height SDS, or BA/chronological age (CA). In Rx group 2, there was a small, nonsignificant increase in PAH, no change in height SDS, and a small decrease in BA/CA. Post-therapy PAH was different from MPTH in all and in both Rx groups 1 and 2, p<0.02. Eight of them achieved near-final height, averaging 6.73 ± 1.40 cm less than MPTH and 1.91 ± 0.86 cm less than the pre-therapy PAH. Post-therapy, the initially decreased estradiol did not persist but mildly increased testosterone and decreased high-density lipoprotein were noted, as was an increase in hematocrit, and decrease in growth velocity.

CONCLUSIONS

We suggest that although bone age progression may be slightly delayed with longer duration of therapy, an overall short-term AI therapy does not lead to a final height that is greater than the predicted pre-therapy height.

Age-based reference ranges for annual height velocity in US children

OBJECTIVE

Clinicians caring for children rely on measures of linear growth as a biomarker of development and overall health. Current reference ranges for height velocity (HV) for US children are unable to provide HV percentiles or Z-scores for early maturing and late maturing children at ages other than age at peak velocity. We present empirically acquired, age-specific reference ranges for HV from a contemporary sample of US youth.

STUDY DESIGN

Subjects were enrolled in the Bone Mineral Density in Childhood Study, a large, multicenter, multiethnic, contemporary cohort of children (aged 5-19 y at enrollment) from the United States followed for up to 7 years. More than 4000 annual (12 ± 1 mo) HV measurements from approximately 1500 children were available. Pubertal status was determined by breast stage or testicular volume assessed by experienced health providers. Age-specific reference ranges were determined using the LMS method.

RESULTS

Reference ranges (third to 97th percentiles) were generated for the entire cohort and for subgroups whose pubertal timing was defined as "earlier," "average," or "later." African American girls experienced earlier pubertal onset and had greater HV at younger ages and lower HV at older ages, compared to non-African American girls; differences did not persist after adjustment for pubertal timing. These differences were not observed for males.

CONCLUSIONS

These reference ranges for annual HV can be used to assess growth relative to peers of the same age and sex, with consideration of pubertal timing. Z-scores and exact percentiles for HV can also be determined for population studies.

Diagnosis and challenges of polycystic ovary syndrome in adolescence

Although the diagnostic criteria for polycystic ovary syndrome (PCOS) have become less stringent over the years, determination of the minimum diagnostic features in adolescents is still an area of controversy. Of particular concern is that many of the features considered to be diagnostic for PCOS may evolve over time and change during the first few years after menarche. Nonetheless, attempts to define young women who may be at risk for development of PCOS is pertinent since associated morbidity such as obesity, insulin resistance, and dyslipidemia may benefit from early intervention. The relative utility of diagnostic tools such as persistence of anovulatory cycles, hyperandrogenemia, hyperandrogenism (hirsutism, acne, or alopecia), or ovarian findings on ultrasound is not established in adolescents. Some suggest that even using the strictest criteria, the diagnosis of PCOS may not valid in adolescents younger than 18 years. In addition, evidence does not necessarily support that lack of treatment of PCOS in younger adolescents will result in untoward outcomes since features consistent with PCOS often resolve with time. The presented data will help determine if it is possible to establish firm criteria which may be used to reliably diagnose PCOS in adolescents.

Weight loss after bariatric surgery in morbidly obese adolescents with MC4R mutations

OBJECTIVE

To determine the frequency of Melanocortin 4 Receptor (MC4R) mutations in morbidly obese adolescents undergoing bariatric surgery and compare weight loss outcomes in patients with and without mutations.

DESIGN AND METHODS

In this prospective cohort study, 135 adolescent patients evaluated for bariatric surgery were screened for MC4R mutations; 56 had 12-month postoperative data available for analysis.

RESULTS

MC4R mutations were detected in five of the 135 patients (3.7%); four underwent restrictive bariatric surgery. For the three patients with gastric banding, percent excess weight loss (%EWL) postoperatively was 36.0% at 5 years in one, 47% at 4 years in the second, and 85% at 1 year in the third. For the patient with gastric sleeve resection, %EWL of 96% was attained at 1 year postoperatively. The four MC4R cases had a higher, although nonsignificant, %EWL compared to 52 nonmatched controls at 12 months postoperatively (48.6% vs. 23.4%; P < 0.37). When matched by age, sex, and race to 14 controls, there was no significant difference in %EWL (P < 0.31), BMI change (P < 0.27), or absolute weight loss (P < 0.20).

CONCLUSION

The frequency of MC4R mutations is similar to prior studies, with affected patients showing beneficial weight loss outcomes.

Rare inheritance of Leri-Weill Syndrome due to crossover of short stature Homeobox Gene (SHOX) Deletions between X and Y Chromosomes: a case report

Background

Leri-Weill syndrome (LWS) is a genetic disorder caused by deletions or mutations in the SHOX gene or by deletions downstream of the gene and is classically characterized by short stature, mesomelic shortening of forearms and legs, and Madelung deformity. Correct identification of short stature homeobox-containing gene (SHOX) deficiency in children with growth problems is vital for appropriate initiation of growth hormone therapy.

Method

We report a phenotypically normal 23 day old male infant born to a father diagnosed with Leri-Weill syndrome at age 12 years with a documented SHOX deletion on his X chromosome. The patient’s fetal long bones had been found to be about three weeks delayed in growth on prenatal ultrasound during the second trimester.

Results

The infant underwent genetic evaluation at 23 days of life and was found to have a SHOX deletion on Yp11.32 identified using single nucleotide polymorphism microarray (SNP) analysis and confirmed by FISH using a SHOX gene probe.

Conclusion

We report the case of a male infant diagnosed with Leri-Weill syndrome with an unusual documented inheritance between father and son due to crossover between X and Y chromosomes during paternal meiosis. Our case is the youngest patient in literature documented by FISH analysis to have an X to Y chromosome transfer and the first of these patients diagnosed prior to onset of short stature or Madelung deformity. Our patient was identified prior to growth failure and can now be monitored for growth abnormalities with the ability to implement growth augmentation therapy without delay. Our case highlights the importance of advising affected SHOX patients of risks to future offspring and supports screening off-spring of parents carrying SHOX abnormalities regardless of sex.

A retrospective review of newborn screening for congenital hypothyroidism and newborn thyroid disease at a major medical center

Objective. To study the frequency of congenital hypothyroidism (CH)/thyroid disorders at a major, urban medical center. Methods. We conducted a retrospective review of a preexisting database for 2007 to 2011. Infants were classified as having CH, secondary/tertiary hypothyroidism, thyroid-binding globulin deficiency, and other types of newborn thyroid dysfunctions. Results. A total of 353 (50%) abnormal newborn screens were found to be normal and 42% were abnormal on repeat. Of the latter, 14% had true CH, 1% had thyroid-binding globulin deficiency, and 27% had other causes of thyroid dysfunction. The 5-year incidence of CH at NYP Morgan Stanley Children's Hospital was significantly greater than in New York City, New York State, and Upstate New York. Conclusion. The incidence of CH and other thyroid dysfunctions were greater in our population for 2007 to 2010, after which there was an unexplained decline. The study underlines the importance of continued newborn screening for thyroid dysfunction.

Hypercalcemia in children receiving pharmacologic doses of vitamin D

Vitamin D deficiency causes rickets, requiring vitamin D at doses greater than daily dietary intake. Several treatment regimens are found in the literature, with wide dosing ranges, inconsistent monitoring schedules, and lack of age-specific guidelines. We describe 3 children, ages 2 weeks to 2 and 9/12 years, who recently presented to our institution with hypercalcemia and hypervitaminosis D (25-hydroxyvitamin D levels >75 ng/mL), associated with treatment of documented or suspected vitamin D-deficient rickets. The doses of vitamin D used were within accepted guidelines and believed to be safe. The patients required between 6 weeks and 6 months to correct the elevated serum calcium, with time to resolution of hypercalcemia related to age and peak serum calcium, but not to peak 25-hydroxyvitamin D level. With recent widespread use of vitamin D in larger dosages in the general population, we provide evidence that care must be taken when using pharmacologic dosing in small children. With limited dosing guidelines available on a per weight basis, the administration of dosages to infants that are often used in older children and adults has toxic potential, requiring a cautious approach in dose selection and careful follow-up. Dosage recommendations may need to be reassessed, in particular, where follow-up and monitoring may be compromised.

Recommendations for treatment of nonclassic congenital adrenal hyperplasia (NCCAH): an update

Congenital adrenal hyperplasia (CAH) is a family of autosomal recessive disorders. 21-Hydroxylase deficiency, in which there are mutations in CYP21A2 (the gene encoding the adrenal 21-hydroxylase enzyme), is the most common form (90%) of CAH. In classic CAH there is impaired cortisol production with diagnostic increased levels of 17-OH progesterone. Excess androgen production results in virilization and in the newborn female may cause development of ambiguous external genitalia. Three-fourths of patients with classic CAH also have aldosterone insufficiency, which can result in salt-wasting; in infancy this manifests as shock, hyponatremia and hyperkalemia. CAH has a reported incidence of 1:10,000-1:20,000 births although there is an increased prevalence in certain ethnic groups. Nonclassic CAH (NCCAH) is a less severe form of the disorder, in which there is 20-50% of 21-hydroxylase enzyme activity (vs. 0-5% in classic CAH) and no salt wasting. The degree of symptoms related to androgen excess is variable and may be progressive with age, although some individuals are asymptomatic. NCCAH has an incidence of 1:1000-1:2000 births (0.1-0.2% prevalence) in the White population; an even higher prevalence is noted in certain ethnic groups such as Ashkenazi Jews (1-2%). As many as two-thirds of persons with NCCAH are compound heterozygotes and carry a severe and mild mutation on different alleles. This paper discusses the genetics of NCCAH, along with its variable phenotypic expression, and reviews the clinical course in untreated patients, which includes rapid early childhood growth, advanced skeletal age, premature adrenarche, acne, impaired reproductive function in both sexes and hirsutism as well as menstrual disorders in females. Finally, it addresses treatment with glucocorticoids vs. non treatment and other therapies, particularly with respect to long term issues such as adult metabolic disease including insulin resistance, cardiovascular disease, metabolic syndrome, and bone mineral density.

Metabolic manifestations of polycystic ovary syndrome in nonobese adolescents: retinol-binding protein 4 and ectopic fat deposition

OBJECTIVE

To determine whether nonobese adolescents with polycystic ovary syndrome (PCOS) have higher levels of retinol-binding protein 4 (RBP4) and ectopic fat than controls and whether RBP4 and ectopic fat correlate with comorbidities of metabolic disease.

DESIGN

Cross-sectional case-control study.

SETTING

Pediatric clinical research center based in a quaternary care medical center.

PATIENT(S)

Twenty-four nonobese adolescents between the ages of 13 and 21 years, 13 with PCOS and 11 controls.

INTERVENTION(S)

Measurement of RBP4, insulin resistance, lipids, and body composition.

MAIN OUTCOME MEASURE(S)

Retinol-binding protein 4, reproductive and adrenal hormones, insulin resistance, intrahepatic and intramyocellular lipid levels, and visceral adipose tissue.

RESULT(S)

Adolescents with PCOS had higher intrahepatic lipid content and a statistical trend for higher RBP4 compared with controls. Retinol-binding protein 4 correlated with body fat, triglycerides, insulin resistance, and androgens but not intrahepatic lipid content; however, when adjusted for body fat, the correlation between RBP4 and triglycerides weakened to a statistical trend and was no longer statistically significant for the other measures.

CONCLUSION(S)

This small preliminary study of nonobese adolescent girls suggests that RBP4 may be involved in the dyslipidemia associated with PCOS and that there may be an independent relationship between RBP4 and triglycerides but not between RBP4 and insulin resistance. Although intrahepatic lipid content was higher in PCOS, it did not correlate with RBP4, triglycerides, or insulin resistance.

Do women with PCOS have a unique predisposition to obesity?

Women with PCOS are often obese and there is debate in the literature regarding whether women are obese because of their PCOS status or if those who become obese are more predisposed to PCOS. There is support for a predisposition to obesity by some data indicating impaired metabolism in PCOS women compared to weight matched controls but this data is limited. Contrary data also exist that adiposity rates do not vary between women with PCOS and those without, and that differences in obesity rates between countries are more likely due to environmental and lifestyle factors. Until further data are available, lifestyle recommendations for weight reduction in women with PCOS should be similar to those for women without PCOS.

Congenital adrenal hyperplasia: an update in children

PURPOSE OF REVIEW

Congenital adrenal hyperplasia (CAH) in children, the majority of which is due to 21-hydroxylase deficiency, represents a group of disorders in which there is impaired cortisol synthesis and abnormalities in adrenal hormonal profiles. There continues to be debate regarding the optimal management of and treatment for these children. This review will highlight the most recent advances in neonatal screening for CAH, as well as the timeliest recommendations for the treatment and management of 21-hydroxylase deficiency, both the classic and nonclassic forms of the disorder.

RECENT FINDINGS

Substantive advancements have been made with regard to neonatal screening for CAH, allowing for earlier diagnosis, while minimizing the morbidity and mortality associated with delayed detection. Although the achievement of normal growth and development remains the ultimate goal of treatment, recent studies have provided further insight into the management and refinement of therapy in these children.

SUMMARY

The optimal management and treatment for children with CAH is still unclear. Although there have been recent advances in the diagnosis and treatment of this group of disorders, there is still much to learn in order to optimize therapy for these individuals.

Approach to the girl with early onset of pubic hair

Premature pubarche, or the development of pubic hair before the age of 8 in girls or 9 in boys, is most commonly caused by premature adrenarche. Adrenarche is the maturation of the adrenal zona reticularis in both boys and girls, resulting in the development of pubic hair, axillary hair, and adult apocrine body odor. Although originally thought to be a benign variant of normal development, premature adrenarche has been associated with insulin resistance and the later development of metabolic syndrome and polycystic ovary syndrome. Although further studies are needed to confirm these relationships, the case presented herein argues for periodic assessment of children at risk. Indeed, recognition of these associations may allow for early preventive measures.

Bone age advancement in prepubertal children with obesity and premature adrenarche: possible potentiating factors

Obesity and premature adrenarche (PA) are both associated with bone age (BA) advancement of unclear etiology, which may lead to earlier puberty, suboptimal final height and obesity in adulthood. Our objective was to understand the hormonal and anthropometric characteristics of BA advancement in a spectrum of prepubertal children with and without obesity and PA. In this cross-sectional study of 66 prepubertal children (35 PA, 31 control, 5-9 years), BMI z-score, hormonal values and response to an oral glucose tolerance test were the main outcome measures. Subjects were divided into tertiles by BA divided by chronological age (BA/CA), an index of BA advancement. Subjects in the top tertile for BA/CA had the highest dehydroepiandrosterone sulfate (DHEAS), free testosterone (%), hemoglobin A(1C), BMI z-score, and weight (P < 0.05). BMI z-score (r = 0.47), weight (r = 0.40), free testosterone (%) (r = 0.34), and DHEAS (r = 0.30) correlated with BA/CA (P < 0.02). Regression analysis showed greater BA/CA in PA compared to controls after controlling for weight (0.21 ± 0.56, P < 0.004). An exploratory stepwise regression model showed that weight, estradiol, and DHEAS were the strongest predictors of BA/CA accounting for 24% of its variance. Obesity was highly associated with BA advancement in this study of prepubertal children. In addition, children with PA had greater BA/CA at any given weight when compared to controls. These findings suggest a possible hormonal factor, which potentiates the effect of obesity on BA advancement in children with obesity and/or PA.

Paternal uniparental isodisomy of the entire chromosome 20 as a molecular cause of pseudohypoparathyroidism type Ib (PHP-Ib)

Pseudohypoparathyoridism type Ib (PHP-Ib) typically defines the presence of end-organ resistance to parathyroid hormone in the absence of Albright's hereditary osteodystrophy. Patients affected by this disorder present with imprinting defects in the complex GNAS locus. Microdeletions within STX16 or GNAS have been identified in familial cases with PHP-Ib, but the molecular cause of the GNAS imprinting defects in sporadic PHP-Ib cases remains poorly defined. We now report a case with sporadic PHP-Ib for whom a SNPlex analysis revealed loss of the maternal GNAS allele. Further analysis of the entire genome with a 100K SNP chip identified a paternal uniparental isodisomy affecting the entire chromosome 20 without evidence for another chromosomal abnormality. Our findings explain the observed GNAS methylation changes and the patient's hormone resistance, and furthermore suggest that chromosome 20 harbors, besides GNAS, no additional imprinted region that contributes to the clinical and laboratory phenotype.

Retinol-binding protein 4 correlates with triglycerides but not insulin resistance in prepubertal children with and without premature adrenarche

BACKGROUND

Retinol-binding protein 4 (RBP4) has been proposed as an early marker for insulin resistance (IR), but no prior studies have addressed RBP4 in an exclusively prepubertal population. Children with premature adrenarche (PA) are at increased risk for IR and metabolic syndrome (MeS); thus finding an appropriate early marker for IR in this population would allow for early intervention and prevention of morbidity related to IR and MeS.

OBJECTIVE

To determine whether prepubertal children with PA have higher levels of RBP4 than controls and whether RBP4 correlates with comorbidities of metabolic disease in prepubertal children.

SUBJECTS

This study comprised 49 prepubertal children (24 with PA and 25 control subjects), 20 boys and 29 girls, who were between the ages of 5 and 9 years.

METHODS

This was a cross-sectional, case-control study conducted in a subspecialty ambulatory clinic based in a quaternary care center. RBP4 levels, hormonal values, lipids, and response to an oral glucose tolerance test were evaluated in children with PA and controls, and body composition measures were obtained in a subset of patients (n = 18).

RESULTS

RBP4 correlated with triglycerides (r = 0.57, p < 0.0001) but did not correlate with IR in a body mass index z-score-adjusted Pearson correlation analysis. There was no difference in RBP4 levels between the PA and control groups.

CONCLUSIONS

These findings suggest that RBP4 may be an early marker of dyslipidemia, which may herald future onset of hepatic IR, polycystic ovary syndrome, and MeS.

Effect of laparoscopic adjustable gastric banding on metabolic syndrome and its risk factors in morbidly obese adolescents

We examined the effect of laparoscopic adjustable gastric banding (LAGB) on weight loss, inflammatory markers, and components of the Metabolic Syndrome (MeS) in morbidly obese adolescents and determined if those with MeS lose less weight post-LAGB than those without. Data from 14-18 yr adolescents were obtained at baseline, 6 and 12 months following LAGB. Significant weight loss and improvements in MeS components were observed 6 months and one year following LAGB. The incidence of MeS declined 56.8% after 6 months and 69.6% after 12 months. There was no significant difference in amount of weight lost post-LAGB between those with and without MeS at either timepoint. Correlations between change in weight parameters and components of MeS in those with and without MeS at baseline were examined and found to vary by diagnostic category. LAGB is effective for short-term improvement in weight, inflammatory markers, and components of MeS in morbidly obese adolescents.

Congenital adrenal hyperplasia due to steroid 21-hydroxylase deficiency: an Endocrine Society clinical practice guideline

OBJECTIVE

We developed clinical practice guidelines for congenital adrenal hyperplasia (CAH).

PARTICIPANTS

The Task Force included a chair, selected by The Endocrine Society Clinical Guidelines Subcommittee (CGS), ten additional clinicians experienced in treating CAH, a methodologist, and a medical writer. Additional experts were also consulted. The authors received no corporate funding or remuneration.

CONSENSUS PROCESS

Consensus was guided by systematic reviews of evidence and discussions. The guidelines were reviewed and approved sequentially by The Endocrine Society's CGS and Clinical Affairs Core Committee, members responding to a web posting, and The Endocrine Society Council. At each stage, the Task Force incorporated changes in response to written comments.

CONCLUSIONS

We recommend universal newborn screening for severe steroid 21-hydroxylase deficiency followed by confirmatory tests. We recommend that prenatal treatment of CAH continue to be regarded as experimental. The diagnosis rests on clinical and hormonal data; genotyping is reserved for equivocal cases and genetic counseling. Glucocorticoid dosage should be minimized to avoid iatrogenic Cushing's syndrome. Mineralocorticoids and, in infants, supplemental sodium are recommended in classic CAH patients. We recommend against the routine use of experimental therapies to promote growth and delay puberty; we suggest patients avoid adrenalectomy. Surgical guidelines emphasize early single-stage genital repair for severely virilized girls, performed by experienced surgeons. Clinicians should consider patients' quality of life, consulting mental health professionals as appropriate. At the transition to adulthood, we recommend monitoring for potential complications of CAH. Finally, we recommend judicious use of medication during pregnancy and in symptomatic patients with nonclassic CAH.

The diagnosis of polycystic ovary syndrome in adolescents

In women, the definition of polycystic ovary syndrome (PCOS) has become broad and includes several possible phenotypes. Because several features of PCOS may be in evolution in adolescents, we suggest that only firm criteria should be used to make a diagnosis of PCOS during adolescence. Hyperandrogenism, oligomenorrhea, and ovarian morphology change during adolescence and are discussed individually. Adolescents with incomplete criteria for a firm diagnosis of PCOS should be followed up carefully and may be diagnosed at a later time.

Screening markers of impaired glucose tolerance in the obese pediatric population

BACKGROUND

With the epidemic of childhood obesity, it is crucial to devise a simple screening protocol to predict impaired glucose tolerance (IGT) or pre-diabetes. The oral glucose tolerance test (OGTT), which is the gold standard for the diagnosis of IGT, is impractical for screening purposes. This pilot study was designed to formulate a simple, sensitive algorithm to predict IGT using clinical and laboratory parameters.

METHODS

Ethnicity, family history of diabetes, pubertal status, BMI z-score, blood pressure, lipids, hemoglobin A1c (HbA1c) and OGTT data were retrospectively collected from 209 overweight multi-ethnic subjects aged 3-21 years. Multivariate logistic regression was used to determine independent predictors of IGT.

RESULTS

HbA1c was the only significant predictor of IGT (p = 0.001), whereas fasting glucose was not. A cut-off of 5.5% had the best combined sensitivity (85.7%) and specificity (56.9%) with an odds ratio of 7.9 of having IGT when HbA1c is > or =5.5%. The remaining clinical parameters were not significant predictors of IGT.

CONCLUSION

While fasting blood glucose does not seem to be a predictor of IGT, we propose that HbA1c > or =5.5% can be used as a screening test to assess the risk of IGT and to determine who should undergo diagnostic OGTT. Large prospective studies validating our findings are warranted.

Serum anti-mullerian hormone concentrations are elevated in oligomenorrheic girls without evidence of hyperandrogenism

CONTEXT

Serum anti-Müllerian hormone (AMH) levels are significantly elevated in adolescents with polycystic ovary syndrome (PCOS) compared to normal controls. Whether adolescents with oligomenorrhea have elevated AMH levels is unknown.

OBJECTIVE

This study was performed to assess serum AMH levels in oligomenorrheic (OLIGO) girls without evidence of hyperandrogenism.

DESIGN

This was a prospective study comparing AMH levels in OLIGO, PCOS, and normal control adolescents.

SETTING

The study was conducted through four tertiary academic medical centers.

PARTICIPANTS

The study groups were comprised of OLIGO (n = 24), PCOS (n = 153), and normal adolescent girls (n = 39), as well as PCOS (n = 73) and normal adult women (n = 36).

INTERVENTIONS

In each subject, serum AMH levels were assessed in the early to midfollicular phases for regularly menstruating subjects and on an arbitrary day for OLIGO or PCOS subjects.

MAIN OUTCOME MEASURE(S)

Basal serum AMH levels were assessed among OLIGO, PCOS, and normal girls, in addition to PCOS and normal women.

RESULTS

OLIGO girls had serum AMH levels (5.33 +/- 0.47 ng/ml) that were significantly greater than the normal adolescents (3.05 +/- 0.31 ng/ml) and adults (2.33 +/- 0.22 ng/ml), but similar to values seen in the PCOS adolescents (5.28 +/- 0.26 ng/ml) and adults (6.36 +/- 0.47 ng/ml). Obese adolescents and PCOS women had significantly lower AMH levels compared to lean controls (P < 0.02).

CONCLUSION

In OLIGO adolescents, elevated serum AMH levels suggest increased antral follicle number similar to that observed in girls with PCOS.

Utility of early insulin response and proinsulin to assess insulin resistance

OBJECTIVE

To determine whether obesity and premature adrenarche are additive events increasing the risk of insulin resistance and beta-cell failure, using early insulin response (EIR) or the insulinogenic index and proinsulin (PI) as markers.

STUDY DESIGN

This was a prospective case-control study conducted at a tertiary care academic medical center involving 81 prepubertal, predominantly Hispanic children (34 males, 47 females), classified as lean controls (4 males, 6 females; mean age, 6.5 +/- 1.2 years; mean body mass index [BMI] z-score, 0.08 +/- 0.6), obese controls (20 males, 10 females; mean age, 7.2 +/- 1.5 years; mean BMI z-score, 2.5 +/- 0.5), lean premature adrenarche (3 males, 11 females; mean age, 7.1 +/- 1.2 years; mean BMI z-score, 0.09 +/- 0.6), and obese premature adrenarche (7 males, 20 females; mean age, 7.3 +/- 1.0; mean BMI z-score, 2.2 +/- 0.4). Fasting glucose (G(0)), insulin (I(0)), PI(0), androgen levels, insulin-like growth factor 1, insulin-like growth factor binding protein 1, and lipid levels were obtained. An oral glucose tolerance test was performed. EIR was calculated as (I(30) - I(0))/(G(30) - G(0)). Between-group differences were assessed by 2-way analysis of variance, with interactions and associations explored with correlation/regression.

RESULTS

EIR was greater in the obese subjects with and without premature adrenarche. Combined analysis of the independent variables obesity and premature adrenarche showed that the obese premature adrenarche group had the highest EIR. The obese subjects with premature adrenarche had greater fasting PI levels than their lean counterparts. The differences in fasting PI/I ratio among the groups were not statistically significant.

CONCLUSIONS

Using EIR and PI as markers to assess the risk of insulin resistance and impaired insulin secretion indicates that obese children with premature adrenarche may be at greater risk for the development of prediabetes and type 2 diabetes mellitus compared with their lean counterparts.

Body composition in premature adrenarche by structural MRI, 1H MRS and DXA

BACKGROUND

Premature adrenarche (PA) is recognized to be a possible precursor of polycystic ovarian syndrome, type 2 diabetes mellitus and cardiovascular disease. Visceral adiposity and increased intramyocellular lipid (IMCL) are associated with insulin resistance and increased risk of cardiovascular disease.

AIM

To determine whether prepubertal girls with PA have altered visceral adiposity and/or increased muscle lipid content compared to prepubertal girls without PA using proton magnetic resonance imaging (MRI) and spectroscopy (1H MRS).

PATIENTS AND METHODS

We performed total body dual energy X-ray absorptiometry (DXA) scans, MRI of the trunk, and MRS of the tibialis anterior muscle in the right calf on six girls with PA and eight prepubertal controls.

RESULTS

Amount of visceral adipose tissue (VAT), abdominal subcutaneous adipose tissue (SAT), and VAT to SAT ratio did not differ significantly between the PA and control girls. Those with PA, however, had significantly greater IMCL than controls (p = 0.004).

CONCLUSIONS

This study adds further evidence that PA is not a benign condition, and future studies investigating early intervention with dietary and exercise counseling may help diminish potential risk for diabetes mellitus and/or cardiovascular disease.

Prenatal diagnosis of congenital lipoid adrenal hyperplasia (CLAH) by estriol amniotic fluid analysis and molecular genetic testing

OBJECTIVE

Congenital lipoid adrenal hyperplasia is an autosomal recessive condition due to mutations in Steroidogenic Acute Regulatory Protein (StAR) associated with the inability to synthesize all adrenal and gonadal steroids, resulting in adrenal insufficiency and failure to develop male genitalia in affected 46,XY individuals. We used two independent methods of prenatal diagnosis for CLAH.

METHOD

CLAH was diagnosed prenatally by measuring amniotic fluid estriol, adrenal, and gonadal hormone levels, and by mutation analysis for the c.201-202 delCT mutation in StAR.

RESULTS

Prenatal testing diagnosed one affected and three unaffected fetuses in two families at risk for CLAH.

CONCLUSION

Prenatal testing for CLAH is effective, and targeted molecular genetic analysis should be considered in Palestinian families with a fetus with discordant 46,XY karyotype and female genitalia on ultrasound, and low maternal serum estriol.

Role of a founder c.201_202delCT mutation and new phenotypic features of congenital lipoid adrenal hyperplasia in Palestinians

CONTEXT

Congenital lipoid adrenal hyperplasia (CLAH), caused by mutations in steroidogenic acute regulatory protein (StAR), is most frequent in Japanese and Palestinians. We report eight Palestinians from four unrelated families with CLAH.

OBJECTIVE

The objective of the study was to identify the mutation(s) in StAR, correlate genotype with phenotype, and determine whether the common mutation represents a founder mutation.

PATIENTS AND SETTING

Clinical, histopathological, and molecular genetic characterization was performed in these eight patients.

RESULTS

All affected individuals (three XY, five XX) presented neonatally with undetectable adrenocortical hormones and are responding to replacement therapy. Only two sisters had neurodevelopmental deficits. Histopathological findings of excised XY gonads included accumulation of fat in Leydig cells. Significantly, already at 1 yr of age, positive placental alkaline phosphatase and octamer binding transcription factor staining indicated neoplastic potential. Sequence analysis of StAR revealed homozygosity for c.201_202delCT mutation in all eight cases, causing premature termination of the StAR protein. This mutation was confirmed to be a founder mutation using both an intragenic microsatellite and several single nucleotide polymorphism markers. Screening of 100 normal Jerusalem Palestinians detected no carriers of this mutation.

CONCLUSION

CLAH is rare in the general Palestinian population. In most Palestinian cases, a founder c.201_202delCT mutation in StAR is the cause. The observed early neonatal presentation may reflect the major StAR protein truncation caused by this mutation. A crucial role for StAR in the central nervous system was not supported with normal neurological examinations in six of eight cases. Finally, we advocate early gonadectomy in XY CLAH cases, given the early onset of neoplastic changes observed histologically.

Hypocalcemic seizures and secondary bilateral femoral fractures in an adolescent with primary vitamin D deficiency

Nutritional rickets and osteomalacia are reemerging in Western societies, particularly in young children and in adolescents of African or Asian descent. Hypocalcemic seizures resulting from vitamin D deficiency are rare in adolescents, whereas fractures caused by seizures without evidence of direct trauma have not yet been reported in this population. We present an unusual case of secondary bilateral femoral fractures caused by hypocalcemic seizures in a 17-year-old boy with primary vitamin D deficiency. We examine the epidemiology and the clinical presentation of rickets and osteomalacia in the adolescent population, the risk of secondary injuries in patients with seizures, and the evaluation and management of hypocalcemic seizures and primary vitamin D deficiency.

Pseudohypoparathyroidism: a rare cause of bilateral slipped capital femoral epiphysis

Pseudohypoparathyroidism (PHP) type 1b is a rare childhood disorder characterized by renal resistance to parathyroid hormone (PTH) resulting in biochemical hypoparathyroidism but with skeletal sensitivity to PTH. We describe a patient with PHP type 1b who we believe is one of the youngest reported patients with bilateral slipped capital femoral epiphyses (SCFE).

Clinical and metabolic characteristics of an obese, Dominican, pediatric population

The prevalence of obesity is particularly high in Black and Latino pediatric populations. A limited number of metabolic studies suggest that race plays a role in the development of obesity-related co-morbidities. We evaluated clinical and metabolic characteristics of 428 obese (mean BMI z-score 2.63) children and adolescents ranging in age from 2-20 years, of primarily Dominican ancestry attending the obesity clinic at Children's Hospital of New York Presbyterian over a 5-year period (1998-2003). Of 193 patients available for detailed metabolic analysis, abnormalities were found for elevated systolic blood pressure (19%), diastolic blood pressure (11%), total cholesterol (18%), LDL (12%), triglycerides (10%), AST (<1%), ALT (4%), low HDL (47%), impaired fasting glucose (5%), impaired glucose tolerance 7%, diabetes mellitus by fasting criteria(<1%), and metabolic syndrome (14%). Despite extraordinary family histories of obesity and diabetes mellitus, the metabolic syndrome and abnormalities of glucose regulation were relatively infrequent compared to studies of obese, pediatric Latino patients of primarily Mexican and Puerto Rican ancestry. This finding suggests that Latinos from different areas of origin may have different risks of obesity-related conditions.

A review of the effects of therapy on growth and bone mineralization in children with congenital adrenal hyperplasia

The medical management of children with congenital adrenal hyperplasia (CAH) can be challenging with regard to optimizing final height. Insufficient glucocorticoid suppression of adrenal hormone production will result in acceleration of bone maturation and premature epiphyseal fusion, while appropriate or excessive glucocorticoid therapy can be accompanied by suppression of the growth axis. The extent of the growth suppression appears to be affected by the type and dose of glucocorticoid. Some studies suggest that such growth suppression can be ameliorated through concomitant use of growth hormone (GH) therapy. Available data published over the last 10 years on height outcomes in CAH patients treated with glucocorticoids will be reviewed.

Growth hormone therapy in children after cranial/craniospinal radiation therapy: sexually dimorphic outcomes

Radiation therapy (RT) to the craniospinal region in childhood affects final height. The use of GH treatment (GHRx) in children after cranial or craniospinal RT results in variable improvement in final height. Nineteen children (12 males and 7 females) with tumors of the head, treated with cranial or craniospinal RT and subsequently with GHRx, were assessed for final height. Two outcome measures of efficacy of GHRx were used: Y1 = final height SD score (SDS) corrected for genetic potential, using midparental sex-adjusted target height (SATH) SDS, and Y2 = change in height SDS from predicted final height SDS pre-GHRx to actual final height SDS post-GHRx. The median age at diagnosis was 5.4 yr, the median RT to the hypothalamic-pituitary axis was 40 Gy, the median spinal RT dose in 13 of 19 of the subjects treated was 36 Gy, and the median years post-RT to GHRx was 4.8 yr. Adjuvant chemotherapy was used in 12 of 19 patients. All but one (optic glioma) had a lesion anatomically distant from the suprasellar region. The effects of age at diagnosis, sex, L-T4 or GnRH agonist use, conventional vs. hyperfractionated RT, spinal RT, dose of spinal or cranial RT, chemotherapy, peak stimulated GH, dose and duration of GHRx, age at GHRx, time interval between RT and GHRx initiation, bone age, and height SDS at the start of GHRx were also assessed. Y1girls best correlated with younger age at diagnosis and im vs. sc GHRx. Y2girls best correlated with delayed bone age and younger age at diagnosis [Y1girls = -9.95 + 0.38 (age in years at diagnosis) + 3.11[GH method (1 = i.m.; 2 = s.c.)]; r2 = 0.898; P = 0.02; Y2girls = -3.54 + 1.8 (bone age - age in years) + 0.334 (age at diagnosis in years); r2= 0.956; P = 0.02]. Both Y1boys and Y2boys were strongly associated with spinal RT and younger age at diagnosis or treatment [Y1boys = -11.22 + 4.65 [spinal RT (1 = yes; 2 = no)] + 0.396 (age in years at diagnosis); r2= 0.64, P = 0.01; Y2boys = -6.32 + 0.23 (age in years at GH start) + 1.75 [spinal RT (1 = yes; 2 = no)]; r2= 0.646; P < 0.01]. This small historical cohort underscores that final stature is significantly reduced when immature bones are exposed to ionizing radiation. Intramuscular vs. sc use of GHRx is likely to be simply a surrogate marker for earlier methods of treatment. Of note, spinal RT did not significantly impact girls' final heights, whereas in boys, spinal RT strongly predicted ultimate short stature and a reduced response to GHRx. This sexually dichotomous response may be due in part to the greater percentage of spinal growth remaining for boys vs. girls throughout childhood.

Growth hormone treatment in children with familial dysautonomia

OBJECTIVE

To assess experience with growth hormone (GH) therapy in patients with familial dysautonomia (FD). Study design Of 580 patients with FD registered at the Dysautonomia Center at New York University Medical Center, 13 patients (8 males, 5 females) aged 1.10 to 15.10 years received GH treatment. GH doses ranged from 0.2 to 0.3 mg/kg/wk; one patient received 0.14 mg/kg/wk. Information regarding auxologic data, skeletal age, pubertal status, and spinal deformity before and after GH therapy was obtained from center records and treating endocrinologists. Growth velocity was analyzed before and during GH treatment at 0 to 6 months, 6 to 12 months, 1 to 2 years, and >2 years.

RESULTS

Before GH therapy, growth velocity was <5 cm/y in 10 patients and 5 to 6 cm/y in three patients. In the first six months of GH therapy, growth velocity exceeded pretreatment rates in all but one patient; 10 patients achieved an annualized growth rate >7 cm/y. Six of nine patients treated for more than one year grew >5 cm/y. Less than optimal treatment responses were attributed to poor compliance, intercurrent illness, scoliosis, or advanced puberty.

CONCLUSION

The data demonstrate that GH treatment in patients with FD may increase growth velocity, at least in the short term. This experiential data supports a future prospective study.

Early endocrine, metabolic, and sonographic characteristics of polycystic ovary syndrome (PCOS): comparison between nonobese and obese adolescents

Approximately half of all women with polycystic ovary syndrome (PCOS) are overweight or obese, and studies have reported endocrine and metabolic differences between lean and obese women with PCOS. PCOS has not been as extensively investigated in the adolescent population. The objectives of our study were to further characterize early endocrine and metabolic alterations in adolescents with PCOS and to determine whether differences between nonobese and obese women with PCOS are present early in its course. We studied an ethnically heterogeneous group of 48 adolescents: 11 nonobese with PCOS [age, 16.1 +/- 1.9 yr; body mass index (BMI), 22.5 +/- 1.5 kg/m(2)], 22 obese with PCOS (age, 15.5 +/- 1.4 yr; BMI, 35.9 +/- 6.2 kg/m(2)), and 15 obese controls (age, 14.4 +/- 1.5 yr; BMI, 35.8 +/- 7.1 kg/m(2)). Fasting levels of glucose, insulin, proinsulin, hemoglobin A1c, testosterone, SHBG, Delta4-androstenedione (Delta4-A), dehydroepiandrosterone sulfate (DHEAS), LH, FSH, IGF-I, IGF binding protein-1, free IGF-I, and lipids were measured. Six of the 11 nonobese PCOS subjects, 11 of the 22 obese PCOS subjects, and six of the 15 controls underwent standard oral glucose tolerance testing. The insulin response to the oral glucose tolerance test was measured by the insulin area under the curve (I(AUC120)). Measures of insulin sensitivity were calculated as the fasting glucose to insulin ratio, quantitative insulin sensitivity check index, and composite insulin sensitivity index. The nonobese adolescents with PCOS demonstrated higher levels of LH, SHBG, Delta4-A, DHEAS, dihydrotestosterone, free IGF-I, and high-density lipoprotein, and lower low-density lipoprotein, compared with the obese PCOS group. Fasting levels of insulin and proinsulin, I(AUC120), and log I(AUC120) were higher, and the fasting glucose to insulin ratio, quantitative insulin sensitivity check index, and composite insulin sensitivity index were lower in the obese compared with the nonobese PCOS subjects. Greater levels of LH and androgens, including total and free testosterone, Delta4-A, and DHEAS, and lower SHBG levels were found in the obese PCOS group compared with the obese controls. Adolescents with PCOS manifest clinical, metabolic, and endocrine features similar to those of adult women, and differences between nonobese and obese women with PCOS may be detected in adolescence. Our findings indicate a more pronounced alteration in the hypothalamo-pituitary-adrenal axis in nonobese adolescents with PCOS and a more marked dysregulation of insulin levels and impairment of insulin sensitivity in their obese counterparts. Our data also suggest differences in the IGF system between nonobese and obese adolescents with PCOS.

Congenital myopathy, recurrent secretory diarrhea, bullous eruption of skin, microcephaly, and deafness: a new genetic syndrome?

We describe three siblings with congenital myopathy, bullous eruption of the skin, secretory diarrhea, apparent zinc deficiency, failure to thrive, deafness, and microcephaly. The parents are not consanguineous and there are no other affected relatives. This new syndrome, which follows an apparent autosomal recessive pattern, appears to be distinct from known syndromes of secretory diarrhea, myopathy, deafness, microcephaly, and zinc deficiency.

Insulin sensitivity and the insulin-like growth factor system in prepubertal boys with premature adrenarche

Girls with premature adrenarche (PA), similar to women with polycystic ovarian syndrome, display alterations in the IGF system, may have impaired insulin sensitivity, and demonstrate unfavorable lipid profiles. Girls with PA are also at increased risk for functional ovarian hyperandrogenism. Metabolic studies in boys with PA, however, are limited. The objective of this study was to determine whether boys with PA show alterations in insulin sensitivity and the IGF system. We studied an ethnically heterogeneous group of 19 prepubertal boys: 11 with PA (age, 8.2 +/- 0.7 yr; body mass index (BMI)-Z score, 1.8 +/- 1.1) and 8 controls (age, 7.9 +/- 0.8 yr; BMI-Z score, 1.2 +/- 1.0). Fasting levels of glucose, insulin, proinsulin (P(0)), hemoglobin A1c, testosterone, SHBG, delta4-androstenedione, dehydroepiandrosterone sulfate, LH, FSH, IGF-I, IGF-binding protein-1, IGF-binding protein-3, free IGF-I, and lipids were measured. Ten of 11 boys with PA and six of eight controls underwent standard oral glucose tolerance testing. The insulin response to this test was measured by the insulin area under the curve. Measures of insulin sensitivity were calculated as the fasting glucose to insulin ratio, quantitative insulin sensitivity check index, and composite insulin sensitivity index. All values were adjusted for BMI-Z score. Total IGF-I, P(0), ratio of P(0) and fasting insulin level, and log insulin area under the curve were higher, and SHBG was lower in the boys with PA, compared with controls. Decreased insulin sensitivity was suggested by decreased composite insulin sensitivity index. A trend toward greater triglycerides was observed in the boys with PA, compared with the controls. Prepubertal boys with PA show differences in the IGF system and decreased insulin sensitivity, independent of obesity, as observed in girls with PA. These findings suggest that both boys and girls with PA should be monitored for the development of insulin resistance and associated complications, including diabetes mellitus and cardiovascular disease.

Proinsulin in girls: relationship to obesity, hyperinsulinemia, and puberty

In adults with impaired glucose tolerance (IGT) and obesity (OB), an elevated proinsulin (PI) is predictive of type 2 diabetes mellitus (DM) and precedes the diagnosis by 5-20 yr. In type 2 DM, the PI is disproportionately elevated, i.e. increased PI/insulin ratio (PI/I). Few studies have evaluated PI in children at risk for type 2 DM. In the face of the current epidemic, we evaluated the relationship of PI and PI/I to IGT, insulin resistance (IR) defined by homeostasis model of assessment (HOMA), degree of OB, and stage of puberty in 70 girls (mean age 10.8 yr; body mass index z-score 3.5; ethnicity 64% Hispanic, 19% white, 16% African-American, and 1% other). Family history of DM was reported in 83%, and acanthosis nigricans was present in 80%. Subjects underwent a 2-h oral glucose tolerance test with glucose, insulin, and PI determinations every 30 min. All had normal hemoglobin A1c and fasting glucose. Five had IGT. With higher HOMA-IR, PI increased (P < 0.05), yet the ratio of fasting PI/I was lower (P < 0.05). Girls with body mass index z-score greater than 4 (n = 29) had higher PI than nonobese girls (n = 19, P < 0.05), but PI/I ratios were not different. PI-0 was increased in late puberty (n = 29), compared with prepuberty (n = 26, P < 0.05), but PI/I ratios showed no statistical difference. We found PI increased with increasing IR and OB in girls. Overall, PI/I was not different, suggesting the elevated PI reflects increased beta-cell output proportional to the elevated insulin in these groups and not a defect in PI processing or secretion. In fact, the lower fasting PI/I of the highest HOMA-IR quartile vs. the lowest HOMA quartile indicates more efficient conversion of PI to I in the presence of increasing IR in these girls.

5 alpha-reductase and 11 beta-hydroxysteroid dehydrogenase activity in prepubertal Hispanic girls with premature adrenarche

Girls with idiopathic premature adrenarche, characterized by the early appearance of pubic hair and adrenal hyperandrogenism, may be at an increased risk for polycystic ovarian syndrome and its associated complications. Alterations of peripheral metabolism of adrenal steroids, specifically increased 5 alpha-reductase and 11 beta-hydroxysteroid dehydrogenase activities, have been documented in patients with polycystic ovarian syndrome and proposed as an underlying mechanism for the adrenal hyperandrogenism in this syndrome. We sought to investigate whether alterations in 5 alpha-reductase and 11 beta-hydroxysteroid dehydrogenase activities are present in girls with premature adrenarche, suggesting a possible role in the pathogenesis of the hyperandrogenism of this condition. We studied C19 and C21 urinary steroid metabolites, 5 alpha/5 beta and 11 oxo/11 hydroxy metabolite pairs as well as the ratios of the total 5 alpha/total 5 beta and total 11 oxo/total 11 hydroxy metabolites in 24-h urine samples from 17 prepubertal Hispanic girls with premature adrenarche and seven controls. We found no differences in the 5 alpha-reductase or 11 beta-hydroxysteroid dehydrogenase activities in the prepubertal girls with premature adrenarche, compared with the controls. When age and body mass index Z-score were controlled for in the statistical analysis, the results did not change. Total cortisol metabolites were not different in the girls with premature adrenarche, compared with the controls. In conclusion, we did not demonstrate a difference in the peripheral steroid metabolism, specifically 5 alpha-reductase and 11 beta-hydroxysteroid dehydrogenase activities, in prepubertal Hispanic girls with premature adrenarche, compared with controls. Therefore, in this group of young girls, alterations in 5 alpha-reductase or 11 beta-hydroxysteroid dehydrogenase activities do not appear to contribute to their early pubic hair development.

Endocrine sequelae in survivors of childhood cancer

Long-term survival after treatment for childhood cancers has dramatically improved in the past 25 years. Overall 5-year survival rates for childhood cancer are greater than 70%. Residual endocrine disorders are as high as 40% in this population, with the most serious disturbances noted in growth and thyroid function. Dysfunction also is observed in the hypothalamic-pituitary-adrenal axis and the hypothalamic-pituitary-gonadal axis, and recent evidence cites alterations in bone and mineral metabolism, body composition, and lipid disorders. These abnormalities are most likely related directly to prior cancer treatment. This chapter focuses on a description of such disorders and offers suggestions for long-term endocrine management and follow-up evaluation.

Elevated free IGF-I levels in prepubertal Hispanic girls with premature adrenarche: relationship with hyperandrogenism and insulin sensitivity

Girls with premature adrenarche (PA) (the onset of pubic hair before the age of 8 yr associated with elevated levels of adrenal androgens and no evidence of true puberty or adrenal dysfunction) may be at increased risk for development of polycystic ovarian syndrome (PCOS). Alterations in the IGF system, including elevated free IGF-I, have been demonstrated in PCOS and may be involved in its pathogenesis. Hyperinsulinemia, elevated total IGF-I, and decreased IGF-binding protein-1 (IGFBP-1) have also been reported in PA. Dysregulation of the IGF system may be involved in the pathogenesis of PA and its progression to PCOS. We compared the insulin/IGF system in 17 prepubertal girls with PA and nine prepubertal controls. Both groups were predominantly obese. Total and free IGF-I were elevated in the premature adrenarche group. No differences in basal insulin, insulin area under the curve in response to an oral glucose tolerance test, or IGFBP-1 were noted. These effects persisted when adjusted for adiposity using body mass index-Z score. Total and free IGF-I were positively correlated, and IGFBP-1 was negatively correlated with Delta4-androstenedione, but not with dehydroepiandrosterone sulfate. Free IGF-I trended toward higher levels in the insulin-resistant subgroup, compared with the insulin-sensitive subgroup. These results suggest altered regulation of the insulin/IGF system in prepubertal girls with PA and a possible role for free IGF-I in the pathogenesis of the hyperandrogenism of PA as well as its progression to PCOS.

Prepubertal girls with premature adrenarche have greater bone mineral content and density than controls

Body composition in premature adrenarche (PA) has not been described. We hypothesized that the increased adrenal androgens in PA would have a trophic effect on lean body components. We studied 14 PA subjects and 16 controls, all prepubertal Hispanic girls. The body composition parameters tested included height, weight, bone mineral density (BMD), bone mineral content (BMC), nonbone fat-free mass, total body potassium, total body water, and extracellular water. Bone age was determined in all PA subjects. Compared with controls, PA subjects had significantly higher BMC (P = 0.02) and BMD (P = 0.03) when adjusted for age, weight, height, and fat mass, but were not different in the following lean body components: fat-free mass, total body potassium, total body water, and extracellular water. There was no difference in BMD or BMC between the PA subjects with and without advanced bone age. These data suggest a specific effect of PA on bone mineral, but not on other lean body components. The absence of a correlation between bone age and bone mineral in this small group leads us to propose there are separate promoters of bone age advancement and bone mineral accrual. Candidate hormones for these processes include adrenal androgens, E, and IGF-I. The findings of this study suggest that hormonal alterations associated with PA affect bone mineral accrual and may elucidate the mechanisms involved in this process.