Weight deficit at birth and Turner's syndrome

Transition from pediatrics to adult health care in girls with turner syndrome

INTRODUCTION

Turner Syndrome is a rare condition secondary to a complete or partial loss of one X chromosome, leading to a wide spectrum of clinical manifestations. Short stature, gonadal dysgenesis, cardiovascular malformations, and dysmorphic features characterize its common clinical picture.

AREAS COVERED

The main endocrine challenges in adolescent girls with Turner Syndrome are puberty induction (closely intertwined with growth) and fertility preservation. We discuss the most important clinical aspects that should be faced when planning an appropriate and seamless transition for girls with Turner Syndrome.

EXPERT OPINION

Adolescence is a complex time for girls and boys: the passage to young adulthood is characterized by changes in the social, emotional, and educational environment. Adolescence is the ideal time to encourage the development of independent self-care behaviors and to make the growing girl aware of her health, thus promoting healthy lifestyle behaviors. During adulthood, diet and exercise are of utmost importance to manage some of the common complications that can emerge with aging. All clinicians involved in the multidisciplinary team must consider that transition is more than hormone replacement therapy: transition in a modern Healthcare Provider is a proactive process, shared between pediatric and adult endocrinologists.

Increased interstage morbidity and mortality following stage 1 palliation in patients with genetic abnormalities

BACKGROUND

Hypoplastic left heart syndrome and single ventricle variants with aortic hypoplasia are commonly classified as severe forms of CHD. We hypothesised patients with these severe defects and reported genetic abnormalities have increased morbidity and mortality during the interstage period.

METHODS AND RESULTS

This was a retrospective review of the National Pediatric Cardiology Quality Improvement Collaborative Phase I registry. Three patient groups were identified: major syndromes, other genetic abnormalities, and no reported genetic abnormality. Tukey post hoc test was applied for pairwise group comparisons of length of stay, death, and combined outcome of death, not a candidate for stage 2 palliation, and heart transplant. Participating centres received a survey to establish genetic testing and reporting practices. Of the 2182 patients, 110 (5%) had major genetic syndromes, 126 (6%) had other genetic abnormalities, and 1946 (89%) had no genetic abnormality. Those with major genetic syndromes weighed less at birth and stage 1 palliation. Patients with no reported genetic abnormalities reached full oral feeds sooner and discharged earlier. The combined outcome of death, not a candidate for stage 2 palliation, and heart transplant was more common in those with major syndromes. Survey response was low (n = 23, 38%) with only 14 (61%) routinely performing and reporting genetic testing.

CONCLUSIONS

Patients with genetic abnormalities experienced greater morbidity and mortality during the interstage period than those with no reported genetic abnormalities. Genetic testing and reporting practices vary significantly between participating centres.

Sex dimorphism of weight and length at birth: evidence based on disorders of sex development

BACKGROUND

Males have higher weight and length at birth than females.

AIM

To verify the influence of the Y chromosome and the action of intrauterine androgens on weight and length at birth of children with Disorders of Sex Development (DSD).

SUBJECTS AND METHODS

A cross-sectional and retrospective study. Patients with Turner syndrome (TS), complete (XX and XY), mixed (45,X/46,XY) and partial (XY) gonadal dysgenesis (GD), complete (CAIS) and partial (PAIS) androgen insensitivity syndromes and XX and XY congenital adrenal hyperplasia (CAH) were included. Weight and length at birth were evaluated.

RESULTS

Weight and length at birth were lower in TS and mixed GD when compared to XY and XX DSD cases. In turn, patients with increased androgen action (117 cases) had higher weight and length at birth when compared to those with absent (108 cases) and decreased (68 cases) production/action. In birthweight, there was a negative influence of the 45,X/46,XY karyotype and a positive influence of increased androgen and gestational age. In birth length, there was a negative influence of the 45,X and 45,X/46,XY karyotypes and also a positive influence of increased androgen and gestational age.

CONCLUSIONS

The sex dimorphism of weight and length at birth could possibly be influenced by intrauterine androgenic action.

Association between clinical variations and copy number variations in cases with Turner syndrome

OBJECTIVES

Turner syndrome (TS) is one of the most common chromosomal abnormalities with an incidence of approximately one in 2,500 live births. Short stature and primary ovarian insufficiency are two most important characteristic findings of TS. Turner syndrome karyotypes include monosomy X, mosaic structure and X chromosome structural anomalies. Genotypic and phenotypic characteristics vary among cases. This study aimed to evaluate the clinical variations observed in TS cases with the copy number variations (CNV) detected by microarray study.

METHODS

Fifty-three patients diagnosed with TS, between the ages of 0-18 were included in the study. Peripheral blood samples were taken from 36 cases for microarray study.

RESULTS

Karyotypes were as follows: thirty-three of cases were 45,X, 7 were 45,X/46,XX, 6 were 45,X/46,Xi(Xq), 2 were 46,Xi(Xq), 2 were 45,X/46,r(X), 1 was 45,X/46,Xi(Xp), 1 was 45,X/46,XY and 1 was 45,X/46,X+mar(idicY) karyotype. A significant correlation was found between karyotype groups and FSH values of the cases (p=0.034). In monosomy X and mosaic isochromosome Xq cases, the FSH value was found to be significantly higher than those with 45,X/46,XX mosaic karyotype. CNVs were found in 8 (22.2%) out of 36 cases whose microarray study was performed. Unexpected atypical findings were discussed in the light of the characteristics of CNVs.

CONCLUSIONS

In conclusion, the microarray method has a great contribution in explaining many unexpected findings in TS cases. Moreover, those CNV findings may contribute for the explanation of the underlying mechanisms of those anomalies.

The Hypothesis of the Prolonged Cell Cycle in Turner Syndrome

Turner syndrome (TS) is a chromosomal disorder that is caused by a missing or structurally abnormal second sex chromosome. Subjects with TS are at an increased risk of developing intrauterine growth retardation, low birth weight, short stature, congenital heart diseases, infertility, obesity, dyslipidemia, hypertension, insulin resistance, type 2 diabetes mellitus, metabolic syndrome, and cardiovascular diseases (stroke and myocardial infarction). The underlying pathogenetic mechanism of TS is unknown. The assumption that X chromosome-linked gene haploinsufficiency is associated with the TS phenotype is questioned since such genes have not been identified. Thus, other pathogenic mechanisms have been suggested to explain this phenotype. Morphogenesis encompasses a series of events that includes cell division, the production of migratory precursors and their progeny, differentiation, programmed cell death, and integration into organs and systems. The precise control of the growth and differentiation of cells is essential for normal development. The cell cycle frequency and the number of proliferating cells are essential in cell growth. 45,X cells have a failure to proliferate at a normal rate, leading to a decreased cell number in a given tissue during organogenesis. A convergence of data indicates an association between a prolonged cell cycle and the phenotypical features in Turner syndrome. This review aims to examine old and new findings concerning the relationship between a prolonged cell cycle and TS phenotype. These studies reveal a diversity of phenotypic features in TS that could be explained by reduced cell proliferation. The implications of this hypothesis for our understanding of the TS phenotype and its pathogenesis are discussed. It is not surprising that 45,X monosomy leads to cellular growth pathway dysregulation with profound deleterious effects on both embryonic and later stages of development. The prolonged cell cycle could represent the beginning of the pathogenesis of TS, leading to a series of phenotypic consequences in embryonic/fetal, neonatal, pediatric, adolescence, and adulthood life.

PPARGC1A promoter DNA-methylation level and glucose metabolism in Ecuadorian women with Turner syndrome

OBJECTIVES

Reduced gene expression of PPARGC1A in subjects with insulin resistance (IR) has been reported. Insulin resistance occurs early on the course of Turner syndrome (TS). The main objective of this study was to evaluate the relationship between PPARGC1A promoter DNA methylation status in lymphocytes and insulin sensitivity and secretion in Ecuadorian females with TS.

METHODS

We examined a cohort of 34 Ecuadorian patients with TS along with a sex-, age- and BMI-matched reference group. All subjects received a standard 75 g oral glucose tolerance test. Insulin resistance and secretion indices were calculated. The PPARGC1A methylated DNA/unmethylated DNA ratio and mitochondrial content (mtDNA/nDNA ratio) were further determined.

RESULTS

Notably, the PPARGC1A DNA methylation level was significantly higher in TS subjects than the reference group and correlated with IR indices. Conversely, mitochondrial content was significantly lower in the study group than healthy controls and negatively correlated with the PPARGC1A methylated DNA/unmethylated DNA ratio in TS individuals. PPARGC1A promoter DNA methylation status contributed to 20% of the total variability in Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) independently of BMI or age in TS subjects.

CONCLUSIONS

Our collective findings suggest that expression of PPARGC1A and lower mitochondrial number affect the metabolic phenotype in TS subjects.

Turner Syndrome: for successful treatment it is necessary to diagnose it early

BACKGROUND

Turner Syndrome (TS) is a chromosomal disorder with short stature as the most common feature. The aim of this paper was to show the characteristics of TS patients treated at our Clinic, with an emphasis on their age at diagnosis and the effect of growth hormone therapy on their final height and height gain.

METHODS

This retrospective study is based on the medical records of 37 female pediatric patients aged 0-18 years treated at the Pediatric Department of the Sestre Milosrdnice University Hospital Center from 1997 to 2017.

RESULTS

Mean age at diagnosis is 7.55±5.13 years. In the observed period a trend towards later diagnosis was shown (P=0.004). Most patients (26) were treated with rhGH. The average height of all patients who reached their final height (N.=30) was 151.49±6.49 cm (standard deviation score [SDS]: -1.73±1.11). The initial height SDS was significantly lower in the treated compared to the untreated patients (P=0.02). The final height was 151.59±7.21 cm (SDS: -1.72±1.3) in the treated and 151.12±5.85 cm (SDS: -1.77±0.94) in the untreated patients. The difference between the initial and final height was significantly greater in the treated patients compared to the untreated patients (30.46 and 16.28 cm, P=0.039). The same was true for the difference between the initial and final height SDS (0.78, or -0.3, P=0.042).

CONCLUSIONS

Based on the results of this research, TS is increasingly diagnosed at a later age. The effect of rhGH therapy was favorable and resulted in a greater height gain in the treated patients.

Metabolic Syndrome as a Risk Factor for Sensorineural Hearing Loss in Adult Patients with Turner Syndrome

BACKGROUND AND PURPOSE

Metabolic syndrome (MetS) is a disorder associated with an increased risk of cardiovascular disease. The frequency of each component of MetS in Turner syndrome (TS) subjects is high. An elevated incidence of hearing loss has also been reported in TS. Sensorineural hearing loss (SNHL) affects at least half of young women with TS. The association between MetS and SNHL has not been previously considered in TS. The aim of this study is to evaluate the association between these two conditions.

PATIENTS AND METHODS

Cross-sectional anthropometric, cardio-metabolic and audiological data were obtained from a cohort consisting of unrelated TS subjects (>20 years of age; n = 93). Metabolic syndrome was defined according to the International Diabetes Federation criteria. Types and severity of hearing loss were based on the American Speech Hearing Association guidelines.

RESULTS

Hearing loss was detected in 74% of ears from adult TS subjects and SNHL was observed in half of our TS subjects. The prevalence of MetS in TS subjects with or without SNHL was 64% and 11%, respectively (P < 0.05). After adjusting for age, MetS was related to a ninefold increase in the odds of SNHL. This odds increased in a stepwise manner as the number of MetS components increased.

CONCLUSION

MetS and its individual components were associated factors for SNHL in TS subjects. A reduction in the number and severity of the components of MetS might potentially contribute to decreasing the progression of SNHL at younger ages, but further studies will be needed to explain the underlying pathological mechanism connecting MetS and SNHL.

Epigenetics in Turner syndrome

Background

Monosomy of the X chromosome is the most frequent genetic abnormality in human as it is present in approximately 2% of all conceptions, although 99% of these embryos are spontaneously miscarried. In postnatal life, clinical features of Turner syndrome may include typical dysmorphic stigmata, short stature, sexual infantilism, and renal, cardiac, skeletal, endocrine and metabolic abnormalities.

Main text

Turner syndrome is due to a partial or total loss of the second sexual chromosome, resulting in the development of highly variable clinical features. This phenotype may not merely be due to genomic imbalance from deleted genes but may also result from additive influences on associated genes within a given gene network, with an altered regulation of gene expression triggered by the absence of the second sex chromosome. Current studies in human and mouse models have demonstrated that this chromosomal abnormality leads to epigenetic changes, including differential DNA methylation in specific groups of downstream target genes in pathways associated with several clinical and metabolic features, mostly on autosomal chromosomes. In this article, we begin exploring the potential involvement of both genetic and epigenetic factors in the origin of X chromosome monosomy. We review the dispute between the meiotic and post-zygotic origins of 45,X monosomy, by mainly analyzing the findings from several studies that compare gene expression of the 45,X monosomy to their euploid and/or 47,XXX trisomic cell counterparts on peripheral blood mononuclear cells, amniotic fluid, human fibroblast cells, and induced pluripotent human cell lines. From these studies, a profile of epigenetic changes seems to emerge in response to chromosomal imbalance. An interesting finding of all these studies is that methylation-based and expression-based pathway analyses are complementary, rather than overlapping, and are correlated with the clinical picture displayed by TS subjects.

Conclusions

The clarification of these possible causal pathways may have future implications in increasing the life expectancy of these patients and may provide informative targets for early pharmaceutical intervention.

Turner Syndrome: Diagnostic and Management Considerations for Perinatal Clinicians

The perinatal clinician needs to understand certain essential concepts when encountering an infant with a suspected or confirmed diagnosis of Turner syndrome. This article describes the key clinical features that should prompt testing, the appropriate diagnostic workup, the necessary screening required after diagnosis, and how to best approach family counseling.

Clinical and cytogenetic features of 516 patients with suspected Turner syndrome - a single-center experience

BACKGROUND

Clinical suspicion of Turner syndrome (TS) may be challenging. Short stature and absent puberty are not mandatory and the dysmorphic picture is widely variable. The aim of the study was to describe a representative sample of patients with suspected TS in a single center and to verify which set of features may help discriminate those with TS.

METHODS

This was a retrospective study of patients with suspected TS evaluated between 1989 and 2012 with the same clinical and cytogenetic protocols. Data regarding reason for referral, age and height at diagnosis, birth data, pubertal features and dysmorphisms were analyzed.

RESULTS

TS was diagnosed in 36% of 516 patients; structural chromosome anomalies predominated (42%). Short stature was the main reason for referral of patients with and without TS. The mean age of patients at first visit, with TS or without TS was similar (11.89 and 11.35 years, respectively), however, infants and adolescents predominated in the TS group. The mean full-term birth weight was lower in patients with TS as well as height at diagnosis, but normal height z-score was found in 17% of patients. Spontaneous puberty occurred in 30% of TS patients aged 13 years or more, but most had pubertal delay. Residual lymphedema, webbed neck, cubitus valgus, hyperconvex nails, shield chest, abnormal nipples, pigmented nevi, short fourth metacarpal and shorter height were the best discriminators for girls with TS.

CONCLUSIONS

Though short stature, pubertal delay and typical stigmata should prompt investigation of TS, lack of one of these features should not exclude this hypothesis. Dysmorphisms other than those considered "typical" should be sought on physical examination.

Secular Trends on Birth Parameters, Growth, and Pubertal Timing in Girls with Turner Syndrome

BACKGROUND

Whether children with chromosomal disorders of growth and puberty are affected by secular trends (STs) as observed in the general population remains unanswered, but this question has relevance for expectations of spontaneous development and treatment responses.

OBJECTIVES

The aim of the study was to evaluate STs in birth parameters, growth, and pubertal development in girls with Turner syndrome (TS).

STUDY DESIGN

Retrospective analysis of KIGS data (Pfizer International Growth Database). We included all TS patients who entered KIGS between 1987 and 2012 and were born from 1975 to 2004, who were prepubertal and growth treatment naïve at first entry (total number: 7,219). Pretreatment height and ages at the start of treatment were compared across 5-year birth year groups, with subgroup analyses stratified by induced or spontaneous puberty start.

RESULTS

We observed significant STs across the birth year groups for birth weight [+0.18 SD score (SDS), p < 0.001], pretreatment height at mean age 8 years (+0.73 SDS, p < 0.001), height at the start of growth hormone (GH) therapy (+0.38 SDS, p < 0.001) and start of puberty (+0.42 SDS, p < 0.001). Spontaneous puberty onset increased from 15 to 30% (p < 0.001). Mean age at the start of GH treatment decreased from 10.8 to 7.4 years (-3.4 years; p < 0.001), and substantial declines were seen in ages at onset of spontaneous and induced puberty (-2.0 years; p < 0.001) and menarche (-2.1 years; p < 0.001).

CONCLUSION

Environmental changes leading to increased height and earlier and also more common, spontaneous puberty are applicable in TS as in normal girls. In addition, greater awareness for TS may underlie trends to earlier start of GH therapy and induction of puberty at a more physiological age.

Anthropometric findings from birth to adulthood and their relation with karyotpye distribution in Turkish girls with Turner syndrome

To evaluate the anthropometric features of girls with Turner syndrome (TS) at birth and presentation and the effect of karyotype on these parameters. Data were collected from 842 patients with TS from 35 different centers, who were followed-up between 1984 and 2014 and whose diagnosis age ranged from birth to 18 years. Of the 842 patients, 122 girls who received growth hormone, estrogen or oxandrolone were excluded, and 720 girls were included in the study. In this cohort, the frequency of small for gestational age (SGA) birth was 33%. The frequency of SGA birth was 4.2% (2/48) in preterm and 36% (174/483) in term neonates (P < 0.001). The mean birth length was 1.3 cm shorter and mean birth weight was 0.36 kg lower than that of the normal population. The mean age at diagnosis was 10.1 ± 4.4 years. Mean height, weight and body mass index standard deviation scores at presentation were -3.1 ± 1.7, -1.4 ± 1.5, and 0.4 ± 1.7, respectively. Patients with isochromosome Xq were significantly heavier than those with other karyotype groups (P = 0.007). Age at presentation was negatively correlated and mid-parental height was positively correlated with height at presentation. Mid-parental height and age at presentation were the only parameters that were associated with height of children with TS. The frequency of SGA birth was found higher in preterm than term neonates but the mechanism could not be clarified. We found no effect of karyotype on height of girls with TS, whereas weight was greater in 46,X,i(Xq) and 45,X/46,X,i(Xq) karyotype groups.

Prematurity, smallness-for-gestational age and later hospital admissions: a nation-wide registry study

INTRODUCTION

Being born premature or small for gestational age (SGA) is known to be associated with diseases later in life, such as gestational diabetes, hypertension and pre-eclampsia. In this study we examined the association between being born premature or SGA and all diseases diagnosed during hospital admissions later in life.

METHODS

Using Danish nation-wide registries we created a cohort of 1,348,106 persons born 1974-1996 and assessed all unique diagnoses registered in the Danish Patient Registry (DPR) for hospital admissions in the period 1994-2007 (n=27,910,558). We determined the odds ratios for persons born premature or SGA using multivariate logistic regression.

RESULTS

A total of 15,059 unique ICD-10 diagnosis codes were represented in the period. Only diagnoses used at least 100 times were included in the analysis (n=4175). Of these 838 showed an odds ratio that was statistically significantly different from unity for people born premature or SGA. After correcting for multiple testing, 250 remained significant. The diagnoses covered diseases in most organ systems, including cardiovascular, endocrinological, infectious, neurological/neurosurgical, obstetric, orthopedic, psychiatric, lung & urological diseases, and occurred throughout childhood and early adulthood. Novel findings included increased risks for delayed puberty, neurofibromatosis type 1 and ileus and decreased risks of mononucleosis, peritonsillar abscesses, chronic hypothyroidism and several types of fractures and contusions later in life.

CONCLUSION

Being born premature or SGA was associated with significantly altered risks of being admitted to a hospital with a wide range of diseases later in life, affecting almost all organ systems throughout childhood and early adulthood. Our findings may motivate testing in other cohorts and search for novel mechanisms of pathogenesis.

Turner syndrome and metabolic derangements: another example of fetal programming

BACKGROUND AND AIM

Turner syndrome (TS) patients have an increased risk of weight gain and metabolic syndrome. To date, it is unknown what factors are involved in this metabolic process, even though it is recognized that TS patients are frequently born small-for-gestational age. The aim of this study was to evaluate the correlation between lipid and glucose profiles with being overweight and birth weight and length in TS patients.

STUDY DESIGN

This was a cross-sectional study.

SUBJECTS AND OUTCOME MEASURES

Serum glucose, insulin (HOMA-IR), total cholesterol, and triglycerides were measured in 64 patients with TS. Data regarding birth weight and length and current body mass index (BMI) were also evaluated.

RESULTS

Total cholesterol showed a significant negative correlation with birth weight and a positive correlation with BMI; triglycerides showed significant negative correlation with birth weight and length and a positive correlation with BMI; and HOMA-IR showed a significant negative correlation with birth weight and length. Low birth weight and a high BMI were predictive for 28% of total cholesterol and triglycerides; and low birth weight for 22% of HOMA-IR.

CONCLUSIONS

Lipid profile was correlated with a high current BMI and low birth weight and length in TS patients and glucose profile only with low birth weight. Thus far, growth retardation may play a role in metabolic derangements in this group of patients, being considered another example of fetal programming.

Birth weight in children with birth defects

BACKGROUND

Birth defects (BDs) are a serious public health problem in Mexico. The objective of this paper was to identify the frequency of newborns (NBs) that are born small for gestational age with a birth defect.

MATERIALS AND METHODS

A cross-sectional study of NBs from hospitals part of the Mexican Institute of Social Security in Chihuahua, Mexico, was conducted. NBs were classified according to the presence or absence of a BD and according to their weight percentile using regional standards of birth weight.

RESULTS

NBs diagnosed with (n = 263) or without BDs (n = 64,626) were included in this study. A greater proportion of NBs small for gestational age were identified in cases involving BDs (20%), compared with NBs without BDs (9%). Moreover, the average decrease in birth weights of NBs with BDs associated with their digestive system was 210 grams (95% confidence interval [CI], -436/-12), with their genital organs 440 grams (95% CI, -730/-151), involving chromosomal abnormalities 230 grams (95% CI, -435/-26), or with their musculoskeletal system 289 grams (95% CI, -43/-147) according to the gestational age, sex, and condition of the NB (p < 0.05).

CONCLUSIONS

A greater proportion of NBs with BDs were associated with a low birth rate for their gestational age. In addition, some BDs were found to be associated with an impaired birth weight more often than others This suggests that clinical decisions regarding NBs with congenital defects and a lower birth weight for their gestational age should be diagnosed and treated for additional nutritional considerations as needed. Birth Defects Research (Part A), 2011. © 2011 Wiley-Liss, Inc.

The evolutionary social brain: From genes to psychiatric conditions

The commentaries on our target article, “Psychosis and Autism as Diametrical Disorders of the Social Brain,” reflect the multidisciplinary yet highly fragmented state of current studies of human social cognition. Progress in our understanding of the human social brain must come from studies that integrate across diverse analytic levels, using conceptual frameworks grounded in evolutionary biology.