Sarabeth Broder-Fingert

Kisspeptin/Gpr54‐Independent Gonadotrophin‐Releasing Hormone Activity in Kiss1 and Gpr54 Mutant Mice

The kisspeptin/Gpr54 signalling pathway plays a critical role in reproduction by stimulating the secretion of gonadotrophin‐releasing hormone (GnRH), yet mice carrying mutations in Kiss1 (which encodes kisspeptin) or Gpr54 exhibit partial sexual maturation. For example, a proportion of female Kiss1−/− and Gpr54−/− mice exhibit vaginal oestrus, and some male Kiss1−/− and Gpr54−/− mice exhibit spermatogenesis. To characterise this partial sexual maturation, we examined the vaginal cytology of female Kiss1−/− and Gpr54−/− mice over time. Almost all mutant mice eventually enter oestrus, and then spontaneously transition from oestrus to dioestrus and back to oestrus again. These transitions are not associated with ovulation, and the frequency of these transitions increases with age. The oestrus exhibited by female Kiss1−/− and Gpr54−/− mice was disrupted by the administration of the competitive GnRH antagonist acyline, which also resulted in lower uterine weights and, in Kiss1−/− mice, lower serum follicle‐stimulating hormone (FSH) and luteinising hormone (LH) concentrations. Similarly, male Kiss1−/− and Gpr54−/− mice treated with acyline had smaller testicular sizes and an absence of mature sperm. In addition to examining intact Kiss1−/− and Gpr54−/− mice, we also assessed the effects of acyline on gonadotrophin concentrations in gonadectomised mice. Gonadectomy resulted in a significant increase in serum FSH concentrations in male Gpr54−/− and Kiss1−/− mice. Acyline administration to gonadectomised Kiss1−/− and Gpr54−/− male mice lowered serum FSH and LH concentrations significantly. By contrast to males, gonadectomy did not result in significant gonadotrophin changes in female Kiss1−/− and Gpr54−/− mice, but acyline administration was followed by a decrease in LH concentrations. These results demonstrate that, although kisspeptin signalling is critical for the high levels of GnRH activity required for normal sexual maturation and for ovulation, Kiss1−/− and Gpr54−/− mice retain some degree of GnRH activity. This GnRH activity is sufficient to produce significant effects on vaginal cytology and uterine weights in female mice and on spermatogenesis and testicular weights in male mice.

Prevalence of overweight and obesity in a large clinical sample of children with autism.

BACKGROUND Overweight and obesity are major pediatric public health problems in the United States; however, limited data exist on the prevalence and correlates of overnutrition in children with autism. METHODS Through a large integrated health care systems patient database, we identified 6672 children ages 2 to 20 years with an assigned ICD-9 code of autism (299.0), Asperger syndrome (299.8), and control subjects from 2008 to 2011 who had at least 1 weight and height recorded in the same visit. We calculated age-adjusted, sex-adjusted body mass index and classified children as overweight (body mass index 85th to 95th percentile) or obese (≥ 95th percentile). We used multinomial logistic regression to compare the odds of overweight and obesity between groups. We then used logistic regression to evaluate factors associated with overweight and obesity in children with autism, including demographic and clinical characteristics. RESULTS Compared to control subjects, children with autism and Asperger syndrome had significantly higher odds of overweight (odds ratio, 95% confidence interval: autism 2.24, 1.74-2.88; Asperger syndrome 1.49, 1.12-1.97) and obesity (autism 4.83, 3.85-6.06; Asperger syndrome 5.69, 4.50-7.21). Among children with autism, we found a higher odds of obesity in older children (aged 12-15 years 1.87, 1.33-2.63; aged 16-20 years 1.94, 1.39-2.71) compared to children aged 6 to 11 years. We also found higher odds of overweight and obesity in those with public insurance (overweight 1.54, 1.25-1.89; obese 1.16, 1.02-1.40) and with co-occurring sleep disorder (obese 1.23, 1.00-1.53). CONCLUSIONS Children with autism and Asperger syndrome had significantly higher odds of overweight and obesity than control subjects. Older age, public insurance, and co-occurring sleep disorder were associated with overweight or obesity in this population.

GnRH-Deficient Phenotypes in Humans and Mice with Heterozygous Variants in KISS1/Kiss1

CONTEXT KISS1 is a candidate gene for GnRH deficiency. OBJECTIVE Our objective was to identify deleterious mutations in KISS1. PATIENTS AND METHODS DNA sequencing and assessment of the effects of rare sequence variants (RSV) were conducted in 1025 probands with GnRH-deficient conditions. RESULTS Fifteen probands harbored 10 heterozygous RSV in KISS1 seen in less than 1% of control subjects. Of the variants that reside within the mature kisspeptin peptide, p.F117L (but not p.S77I, p.Q82K, p.H90D, or p.P110T) reduces inositol phosphate generation. Of the variants that lie within the coding region but outside the mature peptide, p.G35S and p.C53R (but not p.A129V) are predicted in silico to be deleterious. Of the variants that lie outside the coding region, one (g.1-3659C→T) impairs transcription in vitro, and another (c.1-7C→T) lies within the consensus Kozak sequence. Of five probands tested, four had abnormal baseline LH pulse patterns. In mice, testosterone decreases with heterozygous loss of Kiss1 and Kiss1r alleles (wild-type, 274 ± 99, to double heterozygotes, 69 ± 16 ng/dl; r(2) = 0.13; P = 0.03). Kiss1/Kiss1r double-heterozygote males have shorter anogenital distances (13.0 ± 0.2 vs. 15.6 ± 0.2 mm at P34, P < 0.001), females have longer estrous cycles (7.4 ± 0.2 vs. 5.6 ± 0.2 d, P < 0.01), and mating pairs have decreased litter frequency (0.59 ± 0.09 vs. 0.71 ± 0.06 litters/month, P < 0.04) and size (3.5 ± 0.2 vs. 5.4 ± 0.3 pups/litter, P < 0.001) compared with wild-type mice. CONCLUSIONS Deleterious, heterozygous RSV in KISS1 exist at a low frequency in GnRH-deficient patients as well as in the general population in presumably normal individuals. As in Kiss1(+/-)/Kiss1r(+/-) mice, heterozygous KISS1 variants in humans may work with other genetic and/or environmental factors to cause abnormal reproductive function.

Reproductive functions of kisspeptin and Gpr54 across the life cycle of mice and men

The reproductive phenotypes of nearly two dozen patients with mutations in GPR54 have been reported, as have the phenotypes of four mouse lines mutant for Gpr54 and two lines mutant for Kiss1. These phenotypes demonstrate that kisspeptin/Gpr54 function is required at all phases of the life cycle when the secretion of gonadotropin-releasing hormone (GnRH) is robust. Furthermore, there is phenotypic variability ranging from severe hypogonadism to partial sexual development. Collectively, these findings suggest that kisspeptin and Gpr54 serve as an essential conduit for relaying developmental information to the GnRH neuron.

Racial and Ethnic Differences in Subspecialty Service Use by Children With Autism

OBJECTIVE: To describe racial differences in use of specialty care among children with autism spectrum disorder. METHODS: We identified patients ages 2 to 21 years with an International Classification of Diseases, Ninth Revision code of autism (299.0) seen from 2000 to 2011 at a major academic health center by using a research patient data repository and determined rates of specialty provider visits and procedures by race. We then used logistic regression to determine the associations of rates of subspecialty visits and procedures with race and ethnicity, controlling for gender, age, and payer type. RESULTS: We identified 3615 patients (2935 white, 243 Hispanic, 188 African American, and 249 other). The most striking differences were in use of gastroenterology (GI)/nutrition services. Nonwhite children were less likely to use GI/nutrition specialty providers (African American, odds ratio = 0.32 [95th percentile confidence interval: 0.18–0.55]; Hispanic, 0.32 [0.20–0.51]; other, 0.56 [0.34–0.92]) as well as neurology (African American, 0.52 [0.33–0.83]; Hispanic, 0.40 [0.27–0.59]) and psychiatry/psychology (African American, 0.44 [0.27–0.72]; Hispanic, 0.60 [0.41–0.88]; other, 0.62 [0.38–0.99]). Nonwhite children were less likely to have had GI studies: colonoscopy (African American, 0.23 [0.10–0.53]; Hispanic, 0.26 [0.14–0.50]), endoscopy (African American, 0.31 [0.16–0.58]; Hispanic, 0.27 [0.16–0.46]; other, 0.53 [0.31–0.90]), and stool studies (African American, 0.49 [0.30–0.91]). Hispanic children had lower rates of neurologic and other testing: EEG (Hispanic, 0.53 [0.35–0.78]), brain MRI (African American, 0.37 [0.22–0.63]; Hispanic, 0.62 [0.42–0.90]), sleep study (Hispanic, 0.18 [0.04–0.76]), and neuropsychiatric testing (Hispanic, 0.55 [0.32–0.96]). CONCLUSIONS: We found racial and ethnic differences among children diagnosed with autism in use of care and procedures. Possible explanations for these findings include differences in presentation, referral rates, or referral follow through.

Predictors of Gluten Avoidance and Implementation of a Gluten-Free Diet in Children and Adolescents without Confirmed Celiac Disease

OBJECTIVES To determine independent predictors of gluten avoidance and of a physicians decision to initiate a gluten-free diet (GFD) in children and adolescents without confirmed celiac disease. STUDY DESIGN We performed a structured medical record review of 579 patients aged 1-19 years presenting for evaluation of celiac disease between January 2000 and December 2010 at a large Boston teaching hospital. We collected data including demographic information, medical history, serology, small intestinal biopsy, history of gluten avoidance, and the postworkup recommendation of implementation of a GFD. Predictors of gluten-related issues were identified by multivariate logistic regression. RESULTS Among 579 children without a previous diagnosis of celiac disease (mean age, 8.7 years), 43 (7.4%) had ever avoided gluten. Independent predictors of gluten avoidance were irritability or poor temper (OR, 3.2), diarrhea (OR, 2.5), weight issues (OR, 0.4), pervasive developmental disorder (OR, 5.3), and family history of celiac disease (OR, 2.2). Among 143 children without confirmed celiac disease who underwent diagnostic evaluation, several predictive factors were associated with a physician- recommended/parent-initiated GFD: irritability (OR, 6.4), diarrhea (OR, 3.4), pervasive developmental disorder (OR, 7.9), and positive serology before the referral (OR, 4.3). CONCLUSION Gluten avoidance among children and adolescents without a previous diagnosis of celiac disease is relatively common. The identified predictors suggest that gluten avoidance is associated with nonspecific behavioral and gastrointestinal complaints and perhaps with the perceived dietary responses in another family member thought to have celiac disease.

The Needs of Hospitalized Patients With Autism Spectrum Disorders A Parent Survey

Objective. This survey assessed the in-hospital needs of patients diagnosed with autism spectrum disorders (ASDs). Methods. Parents were recruited to complete a 21-item survey about the needs of their child with an ASD while in the hospital. ASD diagnosis was reported by parents at the time of the survey. The results of the survey were analyzed and evaluated in 3 distinct categories of need. Results. We documented a range of responses associated with ASD-specific needs during hospitalization. Common concerns included child safety and the importance of acknowledging individual communication methods. Conclusions. In a population of children with ASDs, parents report a diverse range of needs while in the hospital. These data support the concept that a pragmatic assessment of individual communication and sensory differences is likely to be essential in the development of an appropriate inpatient care plan.

Age-related patterns in clinical presentations and gluten-related issues among children and adolescents with celiac disease.

OBJECTIVES:Celiac disease (CD) is common and often cited as an “iceberg” phenomenon (i.e., an assumed large number of undiagnosed cases). Recently, atypical or asymptomatic manifestations are becoming more commonly described in older children and adolescents. Moreover, CD diagnosis in children can be complicated by several factors, including its diverse clinical presentations, delay in recognizing CD signs and symptoms, and premature dietary gluten avoidance before the formal diagnosis of CD. To date, few studies have directly examined age-related differences in clinical characteristics and gluten-related issues among children with CD. The aim of this study was to determine age-related patterns in clinical characteristics and gluten-related issues among children with confirmed CD.METHODS:We performed a structured medical record review of biopsy-proven CD patients, aged 0–19 years, between 2000 and 2010 at a large Boston teaching hospital. Data collection included demographics, medical history, gluten-related issues, and diagnostic investigations (CD-specific serology, upper gastrointestinal endoscopy, and small intestinal biopsy). The first positive duodenal biopsy with Marsh III classification defined age of diagnosis. Patients were divided into three age groups for comparisons of the aforementioned characteristics: infant-preschool group (0–5 years), school-aged group (6–11 years), and adolescence group (12–19 years).RESULTS:Among 411 children with biopsy-proven CD, the mean age was 9.5 (s.d. 5.1) years. Most were female (63%) and white (96%). All children had positive CD-specific serology. Most children presented with either abdominal complaints or bowel movement changes. Overall, boys were more common among infant-preschool group compared with the other age groups. More distinct clinical manifestations (vomiting, bowel movement changes, and weight issues) were apparent in the youngest group, whereas school-aged children had more subjective abdominal complaints at the initial presentation. Conversely, the adolescents were most likely to present without any gastrointestinal (GI) symptoms, but not when this was combined with absence of weight issues. Age of diagnosis was not associated with atypical extraintestinal CD presentations. Regarding the gluten-related issues, 10% of school-aged children avoided dietary gluten before the formal CD diagnosis, and 27% of the adolescents reported dietary gluten transgression within the first 12 months of diagnosis, significantly higher than the other age groups. Age differences in histopathology were also found. Whereas the infant-preschool group had a higher proportion of total villous atrophy, the older children were more likely to have gross duodenal abnormalities and chronic duodenitis suggestive of CD at the time of diagnosis.CONCLUSIONS:Children and adolescents with CD have age-related patterns in both the clinical presentations and gluten-related issues. More pronounced clinical and histological features were determined in younger children, whereas older children more commonly presented with solely subjective abdominal complaints or even without any GI symptoms. However, silent and atypical extraintestinal CD presentations were comparable between age groups. In addition to the aforementioned presentations, the higher rates of dietary gluten avoidance and transgression in older children make CD diagnosis and management particularly challenging. These age-related patterns may further increase awareness, facilitate early diagnosis, and improve patient care of pediatric CD.

Safety of Frequent Venous Blood Sampling in a Pediatric Research Population

OBJECTIVE To monitor hematological indices in otherwise healthy children with central precocious puberty who underwent frequent venous sampling as part of a longitudinal clinical research study. STUDY DESIGN Thirty-four female subjects underwent frequent venous sampling (every 10-20 minutes for 8-16 hours) every 6 months for >or=3 years during and after their treatment with a gonadotropin-releasing hormone analogue. Hemoglobin (Hgb), mean corpuscular volume, and ferritin levels were measured before and after each phlebotomy session. RESULTS At baseline, the average Hgb level was 12.5+/-0.7 g/L. At the conclusion of the first sampling session, the Hgb level fell 1.2+/-0.1 g/L, remaining within the reference range for age. At the 3-month follow-up, there was complete recovery of Hgb (12.6+/-0.2 g/L). Longitudinal evaluation every 6 months for as long as 3 years showed no significant differences in Hgb, mean corpuscular volume, or ferritin levels from baseline. No clinically significant adverse effects attributable to phlebotomy were reported. CONCLUSION When appropriate safety guidelines were followed, both acute and long-term frequent venous sampling in a pediatric population was safe. Guidelines include monitoring of hematological indices, phlebotomy volume <10 mL/kg/24 hours, and iron replacement.

Predictors of duodenal bulb biopsy performance in the evaluation of coeliac disease in children.

Aims Studies on the role of duodenal bulb biopsy (DBB) in coeliac disease (CD) evaluation have increased in recent years; growing evidence suggests that the disease can present solely in the duodenal bulb. Moreover, recent CD guidelines recommend obtaining a DBB. The study aim was to examine DBB performance in children undergoing CD evaluation and to identify independent predictors of DBB performance. Methods The authors performed a structured chart review of children aged <18 years who underwent CD evaluation between 2000 and 2010 at a large teaching hospital. The authors collected data including demographics, serology, endoscopy and histopathological findings. Predictors of DBB performance (obtained vs not obtained) were determined using multivariable logistic regression. Results Among 616 children who underwent endoscopy, DBB was performed in 103 children (17%, 95% CI 14% to 20%) with an increasing trend in the more recent years (2008–2010, 25%; 2004–2007, 16%; and 2000–2003, 5%, p<0.001). Three independent predictors of DBB performance were older age at endoscopy (OR 1.05 per year of age), gross gastric antral abnormalities (OR 2.81) and gross duodenal abnormalities (OR 5.55). Regarding the DBB histological findings, patchiness of CD was found in 15%. Positive Marsh III biopsy presented solely on the DBB in 6/103 (6%, 95% CI 2% to 12%) children. Conclusions The authors found a significant increase in DBB performance over time, but the overall performance remains suboptimal. Improving education on obtaining a DBB for CD evaluation is crucial, especially among those children in whom DBB is more likely to be omitted.