Melissa K. Crocker

Pediatric Obesity: Etiology and Treatment

This article reviews factors that contribute to excessive weight gain in children and outlines current knowledge regarding approaches for treating pediatric obesity. Most of the known genetic causes of obesity primarily increase energy intake. Genes regulating the leptin signaling pathway are particularly important for human energy homeostasis. Obesity is a chronic disorder that requires long-term strategies for management. The foundation for all treatments for pediatric obesity remains restriction of energy intake with lifestyle modification. There are few long-term studies of pharmacotherapeutic interventions for pediatric obesity. Bariatric surgical approaches are the most efficacious treatment but, because of their potential risks, are reserved for those with the most significant complications of obesity.

Pediatric obesity: etiology and treatment.

This article reviews factors that contribute to excessive weight gain in children and outlines current knowledge regarding approaches for treating pediatric obesity. Most of the known genetic causes of obesity primarily increase energy intake. Genes regulating the leptin signaling pathway are particularly important for human energy homeostasis. Obesity is a chronic disorder that requires long-term strategies for management. The foundation for all treatments for pediatric obesity remains restriction of energy intake with lifestyle modification. There are few long-term studies of pharmacotherapeutic interventions for pediatric obesity. Bariatric surgical approaches are the most efficacious treatment but, because of their potential risks, are reserved for those with the most significant complications of obesity.

Use of PET/CT with cosyntropin stimulation to identify and localize adrenal rest tissue following adrenalectomy in a woman with congenital adrenal hyperplasia.

CONTEXT Adrenalectomy is an experimental treatment option for select patients with congenital adrenal hyperplasia who have failed medical therapy. After adrenalectomy, adrenal rest tissue can remain in extraadrenal locations, cause recurrent hyperandrogenism, and be difficult to localize. OBJECTIVE The aim of the study was to investigate the usefulness of positron emission tomography/computerized tomography (PET/CT) in identifying adrenal rest tissue. SUBJECT A female with salt-wasting 21-hydroxylase deficiency who had bilateral adrenalectomy at age 17 yr presented with hyperandrogenism at age 32 yr. Pelvic magnetic resonance imaging and ultrasound imaging were nondiagnostic for the source of androgen production. METHODS AND RESULTS A baseline F-18 labeled fluoro-2-deoxy-d-glucose (18F-FDG) PET/CT scan showed no active uptake; however, a second scan preceded by a 250-μg cosyntropin injection identified three areas of active uptake near both ovaries. Subsequent ovarian venous sampling showed elevations in 17-hydroxyprogesterone, androstenedione, and 21-deoxycortisol in both ovarian veins compared to a peripheral vein at baseline and more so after cosyntropin administration. At laparoscopy, three well-circumscribed nodules (2.4 × 0.9 × 1.3 cm, 1.2 × 1.5 × 1.5 cm, and 2 × 1.5 × 1 cm) lying lateral to the fallopian tubes adjacent to the broad ligaments were removed. The paraovarian nodules and previously removed adrenal glands had similar histology and immunohistochemistry. Postoperatively, androgen concentrations were undetectable, with no response to cosyntropin stimulation. CONCLUSIONS Patients with CAH after an adrenalectomy may experience recurrent hyperandrogenism due to adrenal rest tissue. 18F-FDG PET/CT with cosyntropin stimulation accurately identified adrenal rest tissue not visualized with conventional imaging, allowing for successful surgical resection.

Acute effects of betahistine hydrochloride on food intake and appetite in obese women: a randomized, placebo-controlled trial

BACKGROUND Central nervous system histaminergic tone is thought to play a role in appetite regulation. In animal models, histamine receptor 1 (HRH1) agonists and histamine receptor 3 (HRH3) antagonists decrease food intake. OBJECTIVE The objective of this study was to examine the acute effects of betahistine hydrochloride (an HRH1 agonist and HRH3 antagonist) on food intakes and appetites. DESIGN The study was a proof-of-concept, randomized, double-blinded, placebo-controlled, dose-ranging study performed to examine the effects of betahistine in women with class I or II obesity [body mass index (BMI; in kg/m²) of 30-39.99]. After a 24-h placebo run-in period, subjects received a placebo (n = 19) or 48 (n = 19), 96 (n = 17), or 144 (n = 21) mg betahistine/d for 24 h. Treatment was followed by a buffet test meal to assess energy intake. Hunger, satiety, and desire to eat were measured after consuming the meal by using visual analog scales. Data were analyzed by using regression models with the assumption that there would be an increasing effect of betahistine doses. Analyses were adjusted for age, log fat and lean mass, food preferences, and intake during a buffet test meal obtained during the placebo run-in period. RESULTS Of the 79 obese women (mean ± SD age: 42 ± 11 y; BMI: 35 ± 3) enrolled in the study, 76 women completed the study. The betahistine dose did not significantly change intakes from those observed during the run-in period of the buffet test meal (P = 0.78). Hunger, fullness, and desire to eat (all P > 0.62) similarly showed no differences according to the betahistine dose. CONCLUSIONS Betahistine did not produce an effect on food intakes or appetites. More potent histaminergic modulators may be required to elucidate the possible role of histaminergic pathways in human obesity. This trial was registered at clinicaltrials.gov as NCT00459992.

Clinical characterization of patients with autosomal dominant short stature due to aggrecan mutations

Context: Heterozygous mutations in the aggrecan gene (ACAN) cause autosomal dominant short stature with accelerated skeletal maturation. Objective: We sought to characterize the phenotypic spectrum and response to growth-promoting therapies. Patients and Methods: One hundred three individuals (57 females, 46 males) from 20 families with autosomal dominant short stature and heterozygous ACAN mutations were identified and confirmed using whole-exome sequencing, targeted next-generation sequencing, and/or Sanger sequencing. Clinical information was collected from the medical records. Results: Identified ACAN variants showed perfect cosegregation with phenotype. Adult individuals had mildly disproportionate short stature [median height, −2.8 standard deviation score (SDS); range, −5.9 to −0.9] and a history of early growth cessation. The condition was frequently associated with early-onset osteoarthritis (12 families) and intervertebral disc disease (9 families). No apparent genotype–phenotype correlation was found between the type of ACAN mutation and the presence of joint complaints. Childhood height was less affected (median height, −2.0 SDS; range, −4.2 to −0.6). Most children with ACAN mutations had advanced bone age (bone age − chronologic age; median, +1.3 years; range, +0.0 to +3.7 years). Nineteen individuals had received growth hormone therapy with some evidence of increased growth velocity. Conclusions: Heterozygous ACAN mutations result in a phenotypic spectrum ranging from mild and proportionate short stature to a mild skeletal dysplasia with disproportionate short stature and brachydactyly. Many affected individuals developed early-onset osteoarthritis and degenerative disc disease, suggesting dysfunction of the articular cartilage and intervertebral disc cartilage. Additional studies are needed to determine the optimal treatment strategy for these patients.

Treatment of paediatric hyperthyroidism but not hypothyroidism has a significant effect on weight

Objective  Thyroid hormones are involved in metabolic regulation, but the degree to which they affect body weight and body mass index (BMI) in children is unclear. We examined the effect of hypo‐ and hyperthyroidism on weight and BMI at the time of diagnosis and after appropriate treatment.

A pilot study of the effects of niacin administration on free fatty acid and growth hormone concentrations in children with obesity.

Children with obesity have low spontaneous growth hormone (GH) secretion. High circulating free fatty acid (FFA) concentration is believed to inhibit GH secretion in those with obesity. In adults, lipolytic inhibition with niacin lowers FFA and increases GH, but there are no prior studies in children with obesity.

Use of Aromatase Inhibitors in Large Cell Calcifying Sertoli Cell Tumors: Effects on Gynecomastia, Growth Velocity, and Bone Age

CONTEXT Large cell calcifying Sertoli cell tumors (LCCSCT) present in isolation or, especially in children, in association with Carney Complex (CNC) or Peutz-Jeghers Syndrome (PJS). These tumors overexpress aromatase (CYP19A1), which leads to increased conversion of delta-4-androstenedione to estrone and testosterone to estradiol. Prepubertal boys may present with growth acceleration, advanced bone age, and gynecomastia. OBJECTIVE To investigate the outcomes of aromatase inhibitor therapy (AIT) in prepubertal boys with LCCSCTs. DESIGN Case series of a very rare tumor and chart review of cases treated at other institutions. SETTING Tertiary care and referral center. PATIENTS Six boys, five with PJS and one with CNC, were referred to the National Institutes of Health for treatment of LCCSCT. All patients had gynecomastia, testicular enlargement, and advanced bone ages, and were being treated by their referring physicians with AIT. INTERVENTIONS Patients were treated for a total of 6-60 months on AIT. MAIN OUTCOME MEASURES Height, breast tissue mass, and testicular size were all followed; physical examination, scrotal ultrasounds, and bone ages were obtained, and hormonal concentrations and tumor markers were measured. RESULTS Tumor markers were negative. All patients had decreases in breast tissue while on therapy. Height percentiles declined, and predicted adult height moved closer to midparental height as bone age advancement slowed. Testicular enlargement stabilized until entry into central puberty. Only one patient required unilateral orchiectomy. CONCLUSIONS Patients with LCCSCT benefit from AIT with reduction and/or elimination of gynecomastia and slowing of linear growth and bone age advancement. Further study of long-term outcomes and safety monitoring are needed but these preliminary data suggest that mammoplasty and/or orchiectomy may be foregone in light of the availability of medical therapy.

Isolated Large Cell Calcifying Sertoli Cell Tumor in a Young Boy, not Associated with Peutz-Jeghers Syndrome or Carney Complex

BACKGROUND Large cell calcifying sertoli cell tumor (LCCSCT) is an exceedingly rare lesion of the testicle. It is most often seen in patients with Carney complex (CNC) or Peutz-Jeghers syndrome (PJS). We now report the first pediatric patient with what appears to be bilateral LCCSCT and no other conditions or a genetic syndrome, such as PJS or CNC, have been associated with it. METHODS A 10-year-old boy was found to have a right testicular mass during a routine pediatric examination; he underwent right orchiectomy. He was then evaluated clinically for PJS or CNC and underwent genetic testing. His tumor was studied by immunohistochemistry for the expression of calretinin, NY-ESO-1, inhibin, CD99, S100, PLAP, AE1/AE3, Bcl-2, p53, and Mib1. RESULTS Patient did not have clinical features or genetic abnormalities of CNC and PJS. Microscopic features showed large, round or cubical intratubular and aggregated tumor cells with prominent nuclear atypia, large and prominent nucleoli and extensive calcification. In the Immunohistochemical studies, calretinin and inhibin alpha were up regulated in LCCSCT as compared to the adjacent benign Sertoli cells. Meanwhile, NY-ESO-1 and CD99 were down-regulated in LCCSCT. Focally and weakly positive S100 was found in the tumor tissue, but no S100 expression was present in the adjacent Sertoli cells. There was no expression of PLAP, P53, Bcl-2, Mib1 and AE1/AE3 in LCCSCT and adjacent Sertoli cells. Micro-calcifications were found in the other gonad by ultrasonography, suggesting LCCSCT. CONCLUSION LCCSCT is a rare testicular neoplasm, and may present in isolated rather than in more typical association with syndromes such as CNC and PJS.