Association between prenatal glucocorticoid exposure and adolescent neurodevelopment: An observational follow-up study.

INTRODUCTION: Prenatal exposure to supraphysiological glucocorticoid (GC) levels may lead to long-lasting developmental changes in numerous biological systems. Our prior study identified an association between prenatal GC prophylaxis and reduced cognitive performance, electrocortical changes, and altered autonomic nervous system (ANS) activity in children aged 8-9 years. This follow-up study aimed to examine whether these findings persisted into adolescence. MATERIAL AND METHODS: Prospective observational follow-up study involving twenty-one 14- to 15-year-old adolescents born to mothers who received betamethasone for induction of fetal lung maturation in threatened preterm birth, but who were born with a normal weight appropriate for their gestational age (median 37+4 gestational weeks). Thirty-five children not exposed to betamethasone served as the reference group (median 37+6 gestational weeks). The primary endpoint was cognitive performance, measured by intelligence quotient (IQ). Key secondary endpoints included symptoms of attention-deficit/hyperactivity disorder (ADHD) and metabolic markers. Additionally, we determined electrocortical (electroencephalogram), hypothalamus-pituitary-adrenal axis (HPAA), and ANS activity in response to a standardized stress paradigm. RESULTS: No statistically significant group difference was observed in global IQ (adjusted mean: betamethasone 103.9 vs references 105.9, mean difference -2.0, 95% confidence interval [CI]: -7.12 to 3.12, p = 0.44). Similarly, ADHD symptoms, metabolic markers, the overall and stress-induced activity of the HPAA and the ANS did not differ significantly between groups. However, the betamethasone group exhibited reduced electrocortical activity in the frontal brain region (spectral edge frequency-adjusted means: 16.0 Hz vs 17.8 Hz, mean difference -1.83 Hz, 95% CI: -3.21 to -0.45, p = 0.01). CONCLUSIONS: In 14- to 15-year-old adolescents, prenatal GC exposure was not associated with differences in IQ scores or ANS activity compared to unexposed controls. However, decelerated electrocortical activity in the frontal region potentially reflects disturbances in the maturation of cortical and/or subcortical brain structures. The clinical significance of these changes remains unknown. Given the small sample size, selective participation/loss of follow-up and potential residual confounding, these findings should be interpreted cautiously. Further research is required to replicate these results in larger cohorts before drawing firm clinical conclusions.

Associations of a metal mixture with iron status in U.S. adolescents: Evidence from the National Health and Nutrition Examination Survey.

Iron is needed for normal development in adolescence. Exposure to individual environmental metals (e.g., lead) has been associated with altered iron status in adolescence, but little is known about the cumulative associations of multiple metals with Fe status. We used data from the 2017-2018 National Health and Nutrition Examination Survey (NHANES) to examine associations between a metal mixture (lead, manganese, cadmium, selenium) and iron status in 588 U.S. adolescents (12-17 years). We estimated cumulative and interactive associations of the metal mixture with five iron status metrics using Bayesian Kernel Machine Regression (BKMR). Higher concentrations of manganese and cadmium were associated with lower log-transformed ferritin concentrations. Interactions were observed between manganese, cadmium, and lead for ferritin and the transferrin receptor, where iron status tended to be worse at higher concentrations of all metals. These results may reflect competition between environmental metals and iron for cellular uptake. Mixed metal exposures may alter normal iron function, which has implications for adolescent development.

ADHD and Drug Holidays: Effects on Anthropometric Changes during Methylpenidate Treatment.

Objectives: The current study evaluated the long-term effects of methylphenidate (MPH) discontinuation on growth parameters in Turkish children and adolescents with attention-deficit/hyperactivity disorder (ADHD). Experimental design: 432 children and adolescents (aged 6-18 years) with ADHD receiving MPH for at least 1 year between March 2012 and January 2019 were included in a retrospective cohort study. We analyzed weight, height, and body mass index (BMI) standard deviation z scores (SDS) of groups that either did (ADHD-C) or did not (ADHD-DC) discontinue MPH. Growth parameters were converted to z scores as normative values for the Turkish population to compare the measurements at baseline and the last follow-up visit by using the paired sample t-test. Principal observations: In patients from the ADHD-C group, statistically significant negative correlations were found between age at starting MPH and differences in weight and height SDS between baseline and follow-up. Children had a greater reduction in weight and height compared to adolescents. When we evaluated the differences in pre-and post-treatment growth factors, we found no significant differences between the groups in terms of growth parameters. Conclusions: Our data showed that chronic use of MPH was likely responsible for changes in height and weight parameters.

Inhibition of BET Proteins during Adolescence Affects Prefrontal Cortical Development: Relevance to Schizophrenia.

BACKGROUND: The present study investigated the role of proteins from the bromodomain and extra-terminal (BET) family in schizophrenia-like abnormalities in a neurodevelopmental model of schizophrenia induced by prenatal methylazoxymethanol (MAM) administration (MAM-E17). METHODS: An inhibitor of BET proteins, JQ1, was administered during adolescence on postnatal days (P) 23-P29, and behavioural responses (sensorimotor gating, recognition memory) and prefrontal cortical (mPFC) function (long-term potentiation (LTP), molecular and proteomic analyses) studies were performed in adult males and females. RESULTS: Deficits in sensorimotor gating and recognition memory were observed only in MAM-treated males. However, adolescent JQ1 treatment affected animals of both sexes in the control but not MAM-treated groups and reduced behavioural responses in both sexes. An electrophysiological study showed LTP impairments only in male MAM-treated animals, and JQ1 did not affect LTP in the mPFC. In contrast, MAM did not affect activity-dependent gene expression, but JQ1 altered gene expression in both sexes. A proteomic study revealed alterations in MAM-treated groups mainly in males, while JQ1 affected both sexes. CONCLUSIONS: MAM-induced schizophrenia-like abnormalities were observed only in males, while adolescent JQ1 treatment affected memory recognition and altered the molecular and proteomic landscape in the mPFC of both sexes. Thus, transient adolescent inhibition of the BET family might prompt permanent alterations in the mPFC.

Toxic and Teratogenic Effects of Prenatal Alcohol Exposure on Fetal Development, Adolescence, and Adulthood.

Prenatal alcohol exposure (PAE) can have immediate and long-lasting toxic and teratogenic effects on an individual's development and health. As a toxicant, alcohol can lead to a variety of physical and neurological anomalies in the fetus that can lead to behavioral and other impairments which may last a lifetime. Recent studies have focused on identifying mechanisms that mediate the immediate teratogenic effects of alcohol on fetal development and mechanisms that facilitate the persistent toxic effects of alcohol on health and predisposition to disease later in life. This review focuses on the contribution of epigenetic modifications and intercellular transporters like extracellular vesicles to the toxicity of PAE and to immediate and long-term consequences on an individual's health and risk of disease.

Evaluation of Growth Hormone Results in Different Diagnosis and Trend Over 10 Year of Follow-up: A Single Center Experience

Objective: The aim was to evaluate the results of diagnosis, follow-up and treatment of the patients who recieved growth hormone (GH) treatment for the last 10 years and to determine the differences in the process and results over the years. Methods: Anthropometric, clinical, laboratory data, treatment adherence and side effects were evaluated retrospectively in 767 patients who recieved GH treatment between 2009-2018. Patients were grouped as isolated GH deficiency (IGHD), multiple pituitary hormone deficiency (MPHD), small for gestational age (SGA), and Turner syndrome (TS) depending on diagnosis. Results: GH treatment was started in 689 cases (89.8%) with IGHD, 24 (3.1%) with MPHD, 26 (3.4%) with SGA and 28 (3.7%) with TS. Median age of GH treatment onset was the earliest in SGA (8.4 years) and the latest in the IGHD group (12.0 years). At the time of treatment cessation, height standard deviation score (SDS) in IGHD and MPHD was significantly higher than treatment initiation time, whereas there was no significant difference in TS and SGA. One hundred eighty-nine cases reached the final height. Final heights for girls/boys were: IGHD 154/164.9 cm; MPHD 156.2/163.5 cm; TS 146.7 cm; and SGA 145.7/-cm, respectively. Target height SDS-final height SDS median values were IGHD: 0.1, MPHD: 0.6, SGA: 0.5, TS: 2.4 respectively. The patients' treatment compliance was high (92%) and the incidence of side effects was low (2.7%). Conclusion: In our cohort, GH treatment start age was late and no difference in this was observed in the last 10 years. The improvement in the height SDS was most marked in the IGHD and MPHD groups, the least in the TS and SGA groups.

Effect of long-chain polyunsaturated fatty acids in infant formula on long-term cognitive function in childhood: A systematic review and meta-analysis of randomised controlled trials.

STUDY REGISTRATION: PROSPERO registration numbers CRD42018105196 and CRD42018088868.

Phthalate Exposure, Adolescent Health, and the Need for Primary Prevention.

Phthalates, a class of endocrine-disrupting chemicals, are used widely in many consumer products, and exposure can interfere with a range of hormonal functions during early life. These disruptions may alter development during late childhood and adolescence. This article discusses the potential effects of phthalate exposure on adiposity, puberty, and neurodevelopment during late childhood and adolescence. It also highlights studies of behavioral interventions to reduce phthalate exposures and the roles of health care professionals and policy makers in preventing phthalate exposure.

Pubertal development and adult height in patients with congenital hypothyroidism detected by neonatal screening in southern Brazil.

Objectives Adequate treatment of congenital hypothyroidism (CH) is required for normal growth and sexual development. To evaluate pubertal development in patients with permanent CH detected by a statewide Neonatal Screening Program of Paraná and, secondly, to evaluate adult height (AH) in a subgroup of patients. Methods Clinical, laboratory, and auxological data obtained from medical records of 174 patients (123 girls). Results Median chronological age (CA) at treatment initiation was 24 days, and mean initial levothyroxine dose was 11.7 ± 1.9 µg/kg/day; mean CA at puberty onset was 11.5 ± 1.3 years (boys) and 9.7 ± 1.2 years (girls); mean CA in girls who underwent menarche (n=81) was 12.1 ± 1.1 years. Thyroid-stimulating hormone (TSH) values above the normal range were observed in 36.4% of the boys and 32.7% of the girls on puberty onset, and in 44.6% around menarche. Among 15 boys and 66 girls who had reached the AH, the median height z-score value was significantly greater than the target height (TH) z-score value in boys (p=0.01) and in girls (p<0.001). Boys with normal TSH values at puberty onset had greater mean AH z-score compared with boys with TSH values above the normal range (p=0.04). Conclusions In this group, pubertal development in girls with CH was not different from that reported in healthy girls in the general Brazilian population. Boys with higher TSH at puberty onset may have an increased risk of not reaching their potential height compared with those with normal TSH during this period. In a subgroup who attained AH, the median AH z-score was greater than the median TH z-score.

Bone Development in Transgender Adolescents Treated With GnRH Analogues and Subsequent Gender-Affirming Hormones.

CONTEXT: Hormonal interventions in adolescents with gender dysphoria may have adverse effects, such as reduced bone mineral accrual. OBJECTIVE: To describe bone mass development in adolescents with gender dysphoria treated with gonadotropin-releasing hormone analogues (GnRHa), subsequently combined with gender-affirming hormones. DESIGN: Observational prospective study. SUBJECTS: 51 transgirls and 70 transboys receiving GnRHa and 36 transgirls and 42 transboys receiving GnRHa and gender-affirming hormones, subdivided into early- and late-pubertal groups. MAIN OUTCOME MEASURES: Bone mineral apparent density (BMAD), age- and sex-specific BMAD z-scores, and serum bone markers. RESULTS: At the start of GnRHa treatment, mean areal bone mineral density (aBMD) and BMAD values were within the normal range in all groups. In transgirls, the mean z-scores were well below the population mean. During 2 years of GnRHa treatment, BMAD stabilized or showed a small decrease, whereas z-scores decreased in all groups. During 3 years of combined administration of GnRHa and gender-affirming hormones, a significant increase of BMAD was found. Z-scores normalized in transboys but remained below zero in transgirls. In transgirls and early pubertal transboys, all bone markers decreased during GnRHa treatment. CONCLUSIONS: BMAD z-scores decreased during GnRHa treatment and increased during gender-affirming hormone treatment. Transboys had normal z-scores at baseline and at the end of the study. However, transgirls had relatively low z-scores, both at baseline and after 3 years of estrogen treatment. It is currently unclear whether this results in adverse outcomes, such as increased fracture risk, in transgirls as they grow older.

AMPed-up adolescents: The role of age in the abuse of amphetamines and its consequences on cognition and prefrontal cortex development.

Adolescent use of amphetamine and its closely related, methylated version methamphetamine, is alarmingly high in those who use drugs for nonmedical purposes. This raises serious concerns about the potential for this drug use to have a long-lasting, detrimental impact on the normal development of the brain and behavior that is ongoing during adolescence. In this review, we explore recent findings from both human and laboratory animal studies that investigate the consequences of amphetamine and methamphetamine exposure during this stage of life. We highlight studies that assess sex differences in adolescence, as well as those that are designed specifically to address the potential unique effects of adolescent exposure by including groups at other life stages (typically young adulthood). We consider epidemiological studies on age and sex as vulnerability factors for developing problems with the use of amphetamines, as well as human and animal laboratory studies that tap into age differences in use, its short-term effects on behavior, and the long-lasting consequences of this exposure on cognition. We also focus on studies of drug effects in the prefrontal cortex, which is known to be critically important for cognition and is among the later maturing brain regions. Finally, we discuss important issues that should be addressed in future studies so that the field can further our understanding of the mechanisms underlying adolescent use of amphetamines and its outcomes on the developing brain and behavior.

In utero exposure to thiopurines/anti-TNF agents and long-term health outcomes during childhood and adolescence in Denmark.

BACKGROUND: Data on long-term health outcomes of children exposed in utero to thiopurines and anti-TNF medications are lacking. AIMS: To examine the association between in utero exposure to thiopurines and anti-TNF medications and child health outcomes of site-specific groups of infections, using a composite endpoint including psychiatric diagnoses/autism spectrum disorder (ASD)/attention deficit hyperactivity disorder (ADHD), and malignancies during childhood/adolescence. METHODS: A nationwide cohort study based on Danish health registries included 1 311 009 live born children during 1995 through 2015. Outcomes were based on hospital diagnoses (in-patients/out-patients/emergency department contacts). RESULTS: In total, 1048 children were exposed in utero to thiopurines and 1 309 961 were unexposed. The adjusted hazard ratios (HRs) for site-specific groups of infections in the first 3 years of life were close to unity. The adjusted HR of psychiatric diagnoses/ASD/ADHD was 1.11 (95% CI 0.81-1.52). The HR of malignancies was not calculated (only two events among the exposed). In total, 493 children were exposed in utero to anti-TNF medications and 728 055 were unexposed. Within the first year of life, the adjusted HR of respiratory, urological/gynaecological infections and other infections were 1.34 (95% CI 1.03-1.74), 2.36 (95% CI 1.15-4.81) and 1.61 (95% CI 1.21-2.13), respectively. We found no increased risk of other adverse outcomes. CONCLUSIONS: After in utero exposure to thiopurines, we found no increased risk of infections, psychiatric diagnoses/ASD/ADHD, or malignancies during childhood/adolescence. After in utero exposure to anti-TNF medications, the risk of respiratory, urological/gynaecological infections and other infections was increased during the first year of life.

Neuropsychological Effects of Mercury Exposure in Children and Adolescents of the Amazon Region, Brazil.

BACKGROUND: Studies with children exposed to methylmercury (MeHg) through fish consumption in the Brazilian Amazon region report that the high levels of hair Hg are associated with significant decreases in intelligence, memory, attention, and visuospatial processing. OBJECTIVE: To investigate the relationship between mercury exposure and neuropsychological functions in riverside communities of the Brazilian Amazon. METHOD: 263 participants aged 6 to 14 years old were assessed, from resettlement regions, near the Madeira river, Rondônia, Brazil. To assess the neuropsychological functions we used the following instruments: intelligence (WASI), working memory (Corsi Block-Tapping Task and Digit Span), verbal fluency (Word Generation - NEPSY II), inhibitory control (Inhibition Errors - NEPSY II), shifting (Trail Making Test) and manual motor dexterity (Grooved PegBoard Test). Socioeconomic status was obtained through household surveys. Total Hg levels were quantified hair samples (Total HgH) collected from the occipital region of the scalp and analyzed by Cold Vapor Atomic Absorption Spectrometry. RESULTS: The group in the upper quartile of Total HgH levels presented lower scores on the tasks that assessed estimated IQ, visuospatial working memory, semantic knowledge and phonological verbal fluency, when compared to the group in the lower quartile level. A regression analysis controlled for age, sex, and maternal education showed that for each increase of 10 µg/g of Total HgH, there was a decrease around half standard deviation in Verbal IQ, estimated IQ scores, semantic knowledge, phonological verbal fluency and for verbal and visuospatial working memory. CONCLUSIONS: High concentrations of Total Hg in hair were associated with a lower performance in neuropsychological functions tests. The results show that environmental exposure to Hg is associated to children and adolescents' lower neuropsychological performance in the riverine and resettled areas of the Brazilian Amazon region.

Effects of air pollution on the nervous system and its possible role in neurodevelopmental and neurodegenerative disorders.

Recent extensive evidence indicates that air pollution, in addition to causing respiratory and cardiovascular diseases, may also negatively affect the brain and contribute to central nervous system diseases. Air pollution is comprised of ambient particulate matter (PM) of different sizes, gases, organic compounds, and metals. An important contributor to PM is represented by traffic-related air pollution, mostly ascribed to diesel exhaust (DE). Epidemiological and animal studies have shown that exposure to air pollution may be associated with multiple adverse effects on the central nervous system. In addition to a variety of behavioral abnormalities, the most prominent effects caused by air pollution are oxidative stress and neuro-inflammation, which are seen in both humans and animals, and are supported by in vitro studies. Among factors which can affect neurotoxic outcomes, age is considered most relevant. Human and animal studies suggest that air pollution may cause developmental neurotoxicity, and may contribute to the etiology of neurodevelopmental disorders, including autism spectrum disorder. In addition, air pollution exposure has been associated with increased expression of markers of neurodegenerative disease pathologies, such as alpha-synuclein or beta-amyloid, and may thus contribute to the etiopathogenesis of neurodegenerative diseases, particularly Alzheimer's disease and Parkinson's disease.

US Adults' Perceptions About the Harms of Nicotine in Electronic Vapor Products on the Adolescent Brain, United States, 2016-2017.

We used data from the 2016 and 2017 SummerStyles survey (N = 4,186 and 4,066, respectively) to assess US adults' perceptions about the harms of nicotine in electronic vapor products (EVP) to the developing adolescent brain. Of respondents in 2016, 68.5% agreed exposure to nicotine in EVP was harmful, and of respondents in 2017, 62.6% agreed (P < .001). This agreement varied by several covariates. Continued efforts are warranted to educate the public about the risks of EVP use among youth, including the harmful effects of nicotine exposure on the developing adolescent brain.

Exploring Cannabis and Alcohol Co-Use in Adolescents: A Narrative Review of the Evidence.

Objective: Amidst the evolving policy surrounding cannabis legalization in the United States, cannabis use is becoming increasingly prevalent as perceptions of harm decrease, particularly among adolescents. Cannabis and alcohol are commonly used by adolescents and are often used together. However, developmental research has historically taken a "single substance" approach to examine the association of substance use and adolescent brain and behavior rather than examining co-(or poly-substance) use of multiple substances, such as cannabis and alcohol. Thus, the acute effects of cannabis and alcohol, and the impact of co-use of cannabis and alcohol on the adolescent brain, cognitive function and subsequent psychosocial outcomes remains understudied. This narrative review aims to examine the effects of cannabis and alcohol on adolescents across a number of behavioral and neurobiological outcomes. Methods: The PubMed and Google Scholar databases were searched for the last 10 years to identify articles reporting on acute effects of cannabis and alcohol administration, and the effects of cannabis and alcohol on neuropsychological, neurodevelopmental, neural (e.g., structural and functional neuroimaging), and psychosocial outcomes in adolescents. When adolescent data were not available, adult studies were included as support for potential areas of future direction in adolescent work. Results: Current studies of the impact of cannabis and alcohol on adolescent brain and behavior have yielded a complicated pattern. Some suggest that the use of cannabis in addition to alcohol during adolescence may have a "protective" effect, yielding neuropsychological and structural brain outcomes that are better than those for adolescents who use only alcohol. However, other adolescent studies suggest that cannabis and alcohol co-use is associated with negative health and social outcomes such as poorer academic performance and impaired driving. Conclusion: Variation in study methodologies, policy-level limitations and our limited understanding of the developmental neurobiological effects of cannabis preclude the straightforward interpretation of the existing data on adolescent cannabis and alcohol use. Further research on this topic is requisite to inform the development of effective intervention and prevention programs for adolescent substance users, which hinge on a more comprehensive understanding of how cannabis-and its intersection with alcohol-impacts the developing brain and behavior.

Subchronic MK-801 treatment during adolescence induces long-term, not permanent, excitatory-inhibitory imbalance in the rat hippocampus.

Adolescence is a critical neurodevelopmental period for both excitatory and inhibitory (E/I) neurotransmission and often witnesses the typical onsets of schizophrenia. One possibility is that disruptions in adolescent neurodevelopmental processes may produce schizophrenia-like behavioral and neurobiological abnormalities. We previously reported that subchronic treatment of adolescent animals with the N-methyl-D-aspartate (NMDA) receptor antagonist MK-801 induced cognitive deficits and reduced interneuron densities in rat medial prefrontal cortex, and these changes persisted one week after MK-801 exposure. However, it remains unclear how this treatment may affect E/I balance in hippocampus, which has long been associated with the pathophysiology of schizophrenia. Here, we examined hippocampal E/I biomarkers in adolescent rats treated with MK-801 (0.2 mg/kg, i.p., 14 days) and found increases in the ratio of the expression levels of vesicular glutamate transporter-1 (VGluT1) and vesicular gamma-aminobutyric acid (GABA) transporter (VGAT) 24 h and 7 days after MK-801 exposure. Interestingly, the increased VGluT1/VGAT ratio at the two time points was driven by upregulated VGluT1 expression and downregulated VGAT expression, respectively. The decrease in VGAT expression persisted 14 days after MK-801 exposure and recovered two weeks later. No alterations in hippocampal interneuron densities were observed. Behaviorally, the treatment decreased prepulse inhibition at 24 h but not 14 days, after MK-801 exposure. Taken together, these results demonstrate that subchronic NMDA receptor blockade during adolescence induces long-term, but not permanent, E/I imbalance in the rat hippocampus, which could be attributed to the dysregulation of glutamatergic transmission in the short term and of GABAergic transmission in the long term.

Adolescent development and psychosocial functioning after starting cross-sex hormones for gender dysphoria.

Purpose: To assess how adolescent development progresses and psychiatric symptoms develop among transsexual adolescents after starting cross-sex hormone treatment.Materials and methods: Retrospective chart review among 52 adolescents who came into gender identity assessment before age 18, were diagnosed with transsexualism and started hormonal gender reassignment. The subjects were followed over the so-called real-life phase of gender reassignment.Results: Those who did well in terms of psychiatric symptoms and functioning before cross-sex hormones mainly did well during real-life. Those who had psychiatric treatment needs or problems in school, peer relationships and managing everyday matters outside of home continued to have problems during real-life.Conclusion: Medical gender reassignment is not enough to improve functioning and relieve psychiatric comorbidities among adolescents with gender dysphoria. Appropriate interventions are warranted for psychiatric comorbidities and problems in adolescent development.

Developmental fluoride neurotoxicity: an updated review.

BACKGROUND: After the discovery of fluoride as a caries-preventing agent in the mid-twentieth century, fluoridation of community water has become a widespread intervention, sometimes hailed as a mainstay of modern public health. However, this practice results in elevated fluoride intake and has become controversial for two reasons. First, topical fluoride application in the oral cavity appears to be a more direct and appropriate means of preventing caries. Second, systemic fluoride uptake is suspected of causing adverse effects, in particular neurotoxicity during early development. The latter is supported by experimental neurotoxicity findings and toxicokinetic evidence of fluoride passing into the brain. METHOD: An integrated literature review was conducted on fluoride exposure and intellectual disability, with a main focus on studies on children published subsequent to a meta-analysis from 2012. RESULTS: Fourteen recent cross-sectional studies from endemic areas with naturally high fluoride concentrations in groundwater supported the previous findings of cognitive deficits in children with elevated fluoride exposures. Three recent prospective studies from Mexico and Canada with individual exposure data showed that early-life exposures were negatively associated with children's performance on cognitive tests. Neurotoxicity appeared to be dose-dependent, and tentative benchmark dose calculations suggest that safe exposures are likely to be below currently accepted or recommended fluoride concentrations in drinking water. CONCLUSION: The recent epidemiological results support the notion that elevated fluoride intake during early development can result in IQ deficits that may be considerable. Recognition of neurotoxic risks is necessary when determining the safety of fluoride-contaminated drinking water and fluoride uses for preventive dentistry purposes.

Growth and Clinical Characteristics of Children with Floating-Harbor Syndrome: Analysis of Current Original Data and a Review of the Literature.

BACKGROUND: Floating-Harbor syndrome (FHS) is a rare condition characterized by dysmorphic facial features, short stature, and expressive language delay. OBJECTIVE: The aim of this study was to describe a cohort of patients with FHS and review the literature about the response to recombinant human growth hormone (rhGH) therapy. METHODS: Anthropometric and laboratory data from 7 patients with FHS were described. The molecular diagnosis was established by multigene analysis. Moreover, we reviewed the literature concerning patients with FHS treated with rhGH. RESULTS: All 7 patients were born small for gestational age. At first evaluation, 6 patients had a height standard deviation score (SDS) ≤-2 and 1 had short stature in relation to their target height. Bone age was usually delayed, which rapidly advanced during puberty. Nonspecific skeletal abnormalities were frequently noticed, and normal to elevated plasma IGF-I levels were observed in all except 1 patient with growth hormone deficiency. Information about 20 patients with FHS treated with rhGH was analyzed (4 from our cohort and 16 from the literature). The median height changes during the treatment period (approx. 2.9 years) were 1.1 SDS (range from -0.4 to 3.1). Nontreated patients had an adult height SDS of -4.1 ± 1.2 (n = 10) versus -2.6 ± 0.8 SDS (n = 7, p 0.012) for treated patients. CONCLUSION: We observed a laboratory profile compatible with IGF-1 insensitivity in some patients with FHS. Nevertheless, our study suggests that children with FHS may be considered as candidates for rhGH therapy. Further studies are necessary to establish the real benefit and safety of rhGH therapy in these patients.