Epidemiological, endocrine and metabolic features in Turner syndrome

Genetic Basis for Sex Differences in Obesity and Lipid Metabolism

Men and women exhibit significant differences in obesity, cardiovascular disease, and diabetes. To provide better diagnosis and treatment for both sexes, it is important to identify factors that underlie the observed sex differences. Traditionally, sex differences have been attributed to the differential effects of male and female gonadal secretions (commonly referred to as sex hormones), which substantially influence many aspects of metabolism and related diseases. Less appreciated as a contributor to sex differences are the fundamental genetic differences between males and females, which are ultimately determined by the presence of an XX or XY sex chromosome complement. Here, we review the mechanisms by which gonadal hormones and sex chromosome complement each contribute to lipid metabolism and associated diseases, and the current approaches that are used to study them. We focus particularly on genetic approaches including genome-wide association studies in humans and mice, -omics and systems genetics approaches, and unique experimental mouse models that allow distinction between gonadal and sex chromosome effects.

Clinical and genetic characteristics in a group of 45 patients with Turner syndrome (monocentric study)

Introduction

Recent years have seen a shift in perspective on Turner syndrome, as it is no longer considered a significant disability due to therapeutic advances. The delay of diagnosis and the underdiagnosis are common in Turner syndrome, especially because of the great phenotypic variability and lack of firm diagnostic criteria.

Aim

Our first aim was to assess the clinical and the cytogenetic characteristics and growth rate in growth hormone (GH)-treated patients as compared to those with spontaneous growth. The second aim was to analyze the Y chromosomal sequences.

Materials and methods

We analyzed 45 patients diagnosed with Turner syndrome in Genetic Pathology Centre of Cluj Emergency Children’s Hospital. We carried out a study of the clinical features, the correlations between the karyotype and the phenotype, and we also made a research of Y chromosome sequences.

Results

The average age at diagnosis was 8.9±5.4 years. A significant association was observed between the number of external phenotypical abnormalities and internal malformations (r=0.45), particularly the cardiovascular ones (r=0.44). Patients treated with GH showed improvement in growth rate, with final stature significantly better than in untreated patients; benefits following treatment were greater if diagnosis was made before the age of 5 years. Thirteen percent of patients experienced spontaneous and complete puberty, whereas 30% experienced incomplete puberty. Patients with the 45,X genotype had a greater stature deficit and a higher incidence of cardiac malformations, compared with patients with 45,X/46,XX mosaic karyotype. Y chromosome sequences were found in only one patient, who subsequently underwent gonadectomy.

Conclusion

The importance of this study resides, to the best of our knowledge, in the fact that the largest group of patients in Romania was analyzed and assessed. To draw firm conclusions on the most valuable clinical indicators for Turner syndrome diagnosis in clinical practice, studies on large groups of patients should be conducted.

Selenium Status in Patients with Turner Syndrome: a Biochemical Assessment Related with Body Composition

Studies about selenium status in patients with Turner syndrome (TS) are non-existent in the literature. The aim of this study was to evaluate selenium status in patients with TS, while considering the different ages of the studied population and the relation with body composition. In total, 33 patients with TS were evaluated and grouped according to their developmental stages (children, adolescents, and adults). Selenium concentrations in their plasma, erythrocytes, urine, and nails were determined by using hydride generation atomic absorption spectrometry and erythrocyte glutathione peroxidase activity were measured by using Randox commercial kits. Additionally, height, weight, body fat percentage, waist circumference, and waist-height ratio were measured to characterize the patients. No differences in the selenium concentrations in the plasma, erythrocyte, urine, and nails or in the glutathione peroxidase activity were observed among the age groups (p > 0.05). The evaluated selenium levels were less than the established normal ones. The patients with larger waist circumference, body fat percentage, body mass index, and waist-height ratio showed lower glutathione peroxidase enzyme activity (p = 0.023). The present study shows that most patients with TS are deficient in selenium and that those with a greater accumulation of body fat have a lower GPx activity.

Gradually increasing ethinyl estradiol for Turner syndrome may produce good final height but not ideal BMD

Estrogen replacement therapy in Turner syndrome should theoretically mimic the physiology of healthy girls. The objective of this study was to describe final height and bone mineral density (BMD) in a group of 17 Turner syndrome patients (group E) who started their ethinyl estradiol therapy with an ultra-low dosage (1-5 ng/kg/day) from 9.8-13.7 years. The subjects in group E had been treated with GH 0.35 mg/kg/week since the average age of 7.4 years. The 30 subjects in group L, one of the historical groups, were given comparable doses of GH, and conjugated estrogen 0.3125 mg/week ∼0.3125 mg/day was initiated at 12.2-18.7 years. The subjects in group S, the other historical group, were 21 patients who experienced breast development and menarche spontaneously. Final height (height gain < 2 cm/year) in group E was 152.4 ± 3.4 cm and the standard deviation (SD) was 2.02 ± 0.62 for Turner syndrome. The final height in group L was 148.5 ± 3.0 cm with a SD of 1.30 ± 0.55, which was significantly different from the values for group E. The volumetric BMD of group S (0.290 ± 0.026 g/cm³) was significantly different from that of group L or E (0.262 or 0.262 g/cm³ as a mean, respectively). This is the first study of patients with Turner syndrome where estrogen was administered initially in an ultra-low dose and then increased gradually. Our estrogen therapy in group E produced good final height but not ideal BMD.

Concomitant occurrence of Turner syndrome and growth hormone deficiency

Turner syndrome (TS) is a genetic disorder in phenotypic females that has characteristic physical features and presents as partial or complete absence of the second sex chromosome. Growth hormone deficiency (GHD) is a condition caused by insufficient release of growth hormone from the pituitary gland. The concomitant occurrence of TS and GHD is rare and has not yet been reported in Korea. Here we report 2 cases of TS and GHD. In case 1, GHD was initially diagnosed. Karyotyping was performed because of the presence of the typical phenotype and poor response to growth hormone therapy, which revealed 45,X/45,X+mar. The patient showed increased growth velocity after the growth hormone dose was increased. In case 2, a growth hormone provocation test and chromosomal analysis were performed simultaneously because of decreased growth velocity and the typical TS phenotype, which showed GHD and a mosaic karyotype of 45,X/46,XX. The patient showed spontaneous pubertal development. In female patients with short stature, it is important to perform a throughout physical examination and test for hormonal and chromosomal abnormalities because diagnostic accuracy is important for treatment and prognosis.

Sexuality and quality of life in congenital hypogonadisms

Turner syndrome and idiopathic congenital hypogonadism including Kallmann syndrome are conditions associated to a large number of widely known comorbidities that need a medical support forever. One of the characteristics shared by both conditions is the lack of sexual development that influencing the sexuality functioning and quality of life of the affected women. Few studies have been conducted to assess these topics, but they need to be considered in the treatment to all women with hypogonadism. This review on the major medical issues and psychological aspects, also focus in the present knowledge about sexual function and quality of life of women with Turner syndrome and idiopathic congenital hypogonadism, which aims to help in the comprehensive management of these patients.

A 6-year Follow-up survey of health status in middle-aged women with Turner syndrome

OBJECTIVE

Studies suggest younger women with Turner syndrome (TS) have good quality of life. Less is known about everyday functioning in adults with TS. In a 6-year follow-up study, multiple areas of functioning were compared between TS women and controls.

DESIGN

Women with TS and controls were mailed a self-report survey 6 years after a baseline study.

PATIENTS

Fifty-seven women with TS (M age 40·6 ± 11·1 years) and 101 controls (M age 38·8 ± 10·6 years, ns) responded.

MEASUREMENTS

Measures of background information, experienced life strain and presence/impact of health conditions were developed for this study. The QPS Nordic measured perceived workload challenges. The LiSat-9 measured life satisfaction. The Rosenberg Self-Esteem Scale measured self-esteem.

RESULTS

More TS women lived alone, fewer had biological children, and more had adoptive children. TS women reported fewer sex partners and less sexual confidence. Controls had higher education. There was no difference in employment status. More TS women received disability pensions. TS women reported their work as more physically challenging, less positively challenging and requiring less knowledge skills. TS women experienced more life strain in school, adolescence and late working life. Controls reported higher overall life satisfaction, with no difference between samples on specific domains. TS women reported lower self-esteem. For TS women only, physical health at baseline predicted length of education and mental health at baseline predicted self-esteem.

CONCLUSIONS

Women with TS face more challenges than controls on several domains of functioning. Early physical and mental health may influence later educational achievement and self-esteem for women with TS.

Familial Turner syndrome: the importance of information

Turner syndrome is a common genetic disorder with an incidence of 1 in 2500 live births. Spontaneous fertility is rare in such patients and is most likely in women with mosaicism or very distal Xp deletions. The authors report an unusual case of familial Turner syndrome in a woman with mosaicism 45,X/46,Xdel(Xp) karyotype with three documented spontaneous pregnancies, which resulted in two daughters with 46,Xdel(X)(p11.4)mat karyotype and a healthy son. The mother was first diagnosed by the age of 11 and did not receive contraceptive medication, due to information that she would be infertile. Both daughters were referred to an endocrinology unit and are now under growth hormone treatment, and have been growing in the 3rd percentile. This family illustrates the complexity and difficulties in counseling, follow-up and treatment in Turner syndrome, namely referring to a tertiary center, fertility and treatment such as growth hormone and hormonal replacement, due to the heterogeneity of the clinical spectrum.

X-chromosome gene dosage as a determinant of impaired pre and postnatal growth and adult height in Turner syndrome

OBJECTIVE

Short stature is a key aspect of the phenotype of patients with Turner syndrome (TS). SHOX haploinsufficiency is responsible for about two-thirds of the height deficit. The aim was to investigate the effect of X-chromosome gene dosage on anthropometric parameters at birth, spontaneous height, and adult height (AH) after growth hormone (GH) treatment.

DESIGN

We conducted a national observational multicenter study.

METHODS

Birth parameter SDS for gestational age, height, and AH before and after GH treatment respectively, and height deficit with respect to target height (SDS) were classified by karyotype subgroup in a cohort of 1501 patients with TS: 45,X (36%), isoXq (19%), 45,X/46,XX (15%), XrX (7%), presence of Y (6%), or other karyotypes (17%).

RESULTS

Birth weight, length (P<0.0001), and head circumference (P<0.001), height and height deficit with respect to target height (SDS) before GH treatment, at a median age of 8.8 (5.3-11.8) years and after adjustment for age and correction for multiple testing (P<0.0001), and AH deficit with respect to target height at a median age of 19.3 (18.0-21.8) years and with additional adjustment for dose and duration of GH treatment (P=0.006), were significantly associated with karyotype subgroup. Growth retardation tended to be more severe in patients with XrX, isoXq, and, to a lesser extent, 45,X karyotypes than in patients with 45,X/46,XX karyotypes or a Y chromosome.

CONCLUSION

These data suggest that haploinsufficiency for an unknown Xp gene increases the risk of fetal and postnatal growth deficit and short AH with respect to target height after GH therapy.

The Deep Correlation between Energy Metabolism and Reproduction: A View on the Effects of Nutrition for Women Fertility

In female mammals, mechanisms have been developed, throughout evolution, to integrate environmental, nutritional and hormonal cues in order to guarantee reproduction in favorable energetic conditions and to inhibit it in case of food scarcity. This metabolic strategy could be an advantage in nutritionally poor environments, but nowadays is affecting women's health. The unlimited availability of nutrients, in association with reduced energy expenditure, leads to alterations in many metabolic pathways and to impairments in the finely tuned inter-relation between energy metabolism and reproduction, thereby affecting female fertility. Many energetic states could influence female reproductive health being under- and over-weight, obesity and strenuous physical activity are all conditions that alter the profiles of specific hormones, such as insulin and adipokines, thus impairing women fertility. Furthermore, specific classes of nutrients might affect female fertility by acting on particular signaling pathways. Dietary fatty acids, carbohydrates, proteins and food-associated components (such as endocrine disruptors) have per se physiological activities and their unbalanced intake, both in quantitative and qualitative terms, might impair metabolic homeostasis and fertility in premenopausal women. Even though we are far from identifying a "fertility diet", lifestyle and dietary interventions might represent a promising and invaluable strategy to manage infertility in premenopausal women.

The Biology and Evolution of Mammalian Y Chromosomes

Mammals have the oldest sex chromosome system known: the mammalian X and Y chromosomes evolved from ordinary autosomes beginning at least 180 million years ago. Despite their shared ancestry, mammalian Y chromosomes display enormous variation among species in size, gene content, and structural complexity. Several unique features of the Y chromosome--its lack of a homologous partner for crossing over, its functional specialization for spermatogenesis, and its high degree of sequence amplification--contribute to this extreme variation. However, amid this evolutionary turmoil many commonalities have been revealed that have contributed to our understanding of the selective pressures driving the evolution and biology of the Y chromosome. Two biological themes have defined Y-chromosome research over the past six decades: testis determination and spermatogenesis. A third biological theme begins to emerge from recent insights into the Y chromosome's roles beyond the reproductive tract--a theme that promises to broaden the reach of Y-chromosome research by shedding light on fundamental sex differences in human health and disease.

Cytogenetic and Clinical Features in Children Suspected With Congenital Abnormalities in 1 Medical Center of Zhejiang Province From 2011 to 2014

This study aimed to investigate the detection rate of chromosome abnormalities in children suspected with congenital disorders in 1 single center, identify any differences according to different classification criteria, and try to enlighten the medical professionals what clinical features should be transferred for cytogenetic analysis.From January 1, 2011 to March 31, 2014, children who were suspected with chromosomal disorders were included. All the cytogenetic analyses were performed in the Medical Biology and Genetic Department Laboratory in Zhejiang DIAN Diagnostics. We evaluated the variants of clinical indications, and incidence and types of chromosomal abnormalities among groups.During the study period, 4129 samples were collected and analyzed. Among them, 769 children were detected with chromosome abnormalities, accounting for 18.62% of all referral cases. The ratio of sex-linked chromosomal abnormalities to autosomal ones was 1:3.2. The detection rates were 19.66% (365/1857) for boys and 17.78% (404/2272) for girls. Most of trisomy 21 were found before the age of 1 year old, while most of children with Turner syndrome were found after 6 years old. The group presenting with specific clinical stigmata had highest detection rate of 59.1%.We demonstrated the detection rates of chromosome abnormalities in children who were suspected with chromosomal disorders. Combined with previous report, we established a database of common chromosomal anomalies and the clinical features that could be useful for genetic counseling and remind the medical professionals what kind of patients should be transferred to genetic analysis.

TRANSITION IN ENDOCRINOLOGY: Hypogonadism in adolescence

Puberty is a remarkable developmental process with the activation of the hypothalamic-pituitary-gonadal axis culminating in reproductive capacity. It is accompanied by cognitive, psychological, emotional, and sociocultural changes. There is wide variation in the timing of pubertal onset, and this process is affected by genetic and environmental influences. Disrupted puberty (delayed or absent) leading to hypogonadism may be caused by congenital or acquired etiologies and can have significant impact on both physical and psychosocial well-being. While adolescence is a time of growing autonomy and independence, it is also a time of vulnerability and thus, the impact of hypogonadism can have lasting effects. This review highlights the various forms of hypogonadism in adolescence and the clinical challenges in differentiating normal variants of puberty from pathological states. In addition, hormonal treatment, concerns regarding fertility, emotional support, and effective transition to adult care are discussed.

Low myocardial glucose uptake in Turner syndrome is unaffected by growth hormone: a randomized, placebo-controlled FDG-PET study

BACKGROUND

An unfavourable cardiovascular and metabolic phenotype causes threefold excess mortality in Turner syndrome (TS), and perturbed cardiac substrate metabolism is increasingly recognized as a common component of cardiovascular and metabolic diseases. We therefore hypothesized that myocardial glucose uptake (MGU) is reduced in TS and that growth hormone (GH) treatment improves MGU. To this end, this controlled trial elucidates MGU in TS and the impact of 6 months of growth hormone treatment on MGU.

METHODS AND RESULTS

Women with TS (n = 9) were examined at baseline, sequentially treated with either Norditropin(®) SimpleXx or placebo and re-examined after 6 months. MGU and myocardial blood flow (MBF) were measured using 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography (FDG-PET) during a hyperinsulinaemic euglycaemic clamp (at baseline and 6 months). Blood pressure measurement, blood sampling, echocardiography and dual energy X-ray absorptiometry scan were also performed. Age-matched female controls (n = 9) were examined once. Baseline MGU was reduced in TS (0.24 ± 0.08 vs. 0.36 ± 0.13 μmol/g/min in controls; P = 0.036) despite similar insulin sensitivity (whole body glucose uptake (M-value): 9.69 ± 1.86 vs. 9.86 ± 2.58 mg/(min*kg) in controls; P = 0.9). Six months of GH carried no impact on MGU (0.25 ± 0.08 vs. 0.26 ± 0.12 μmol/g/min in the placebo group; P = 0.8). Plasma glucose, low-density cholesterol and triglycerides increased, while M-value and exercise capacity decreased during 6 months of GH treatment.

CONCLUSION

MGU is reduced in TS despite normal insulin sensitivity. GH treatment does not alter MGU despite decreased whole body insulin sensitivity. A perturbed cardiac glucose uptake appears to be a feature of TS.

Perspectives in Pediatric Pathology, Chapter 5. Gonadal Dysgenesis

One of the most challenging areas in pediatric testicular pathology is the appropriate understanding and pathological diagnosis of disorders of sexual development (DSD), and in particular, the issue of gonadal dysgenesis. Here we present the main concepts necessary for their understanding and appropriate classification, with extensive genetic correlations.

Cardiometabolic and vascular risks in young and adolescent girls with Turner syndrome

BACKGROUND

Turner syndrome (TS) is the most common chromosomal abnormality in females and is associated with several co-morbidities. It commonly results from X monosomy which is diagnosed on a 30 cell karyotype. Congenital heart disease is a clinical feature in 30% of cases. It is becoming evident that TS patients have an increased risk of cardiovascular and cerebrovascular diseases.

SCOPE OF REVIEW

This review provides a detailed overview of the literature surrounding cardiometabolic health in childhood and adolescent TS. In addition, the review also summarises the current data on the impact of growth hormone (GH) therapy on cardiometabolic risk in paediatric TS patients.

MAJOR CONCLUSIONS

Current epidemiological evidence suggests that young women and girls with TS have unfavourable cardiometabolic risk factors which predispose them to adverse cardiac and cerebrovascular outcomes in young adulthood. It remains unclear whether this risk is the result of unidentified factors which are intrinsic to TS, or whether modifiable risk factors (obesity, hypertension, hyperglycaemia) are contributing to this risk.

GENERAL SIGNIFICANCE

From a clinical perspective, this review highlights the importance of regular screening and pro-active management of cardiometabolic risk from childhood in TS cohorts and that future research should aim to address whether modification of these variables at a young age can alter the disease process and atherosclerotic outcomes in adulthood.

Amelioration of oxidative stress and insulin resistance by soy isoflavones (from Glycine max) in ovariectomized Wistar rats fed with high fat diet: the molecular mechanisms

Estrogen deficiency after menopause accelerates the redox imbalance and insulin signaling, leading to oxidative stress (OS) and insulin resistance (IR). The molecular mechanisms by which the loss of ovarian hormone leads to OS and IR remain unclear. In the present study we found that rats when subjected to ovariectomy (OVX) resulted in reduction of whole blood antioxidants and elevation of oxidant markers. The expression of anti-oxidant enzymes, superoxide dismutase (SOD1) and glutathione peroxidase (GPX1) was suppressed whereas the pro-oxidative enzyme NADPH oxidase (NOX4) and mitogen activated protein (MAP) kinases ERK 1/2 and p38 were increased at different tissues. Treatment with soy (SIF, 150 mg/kg BW for 12 weeks) extract markedly reversed these metabolic changes and improved OS. Ovariectomized rats also displayed glucose intolerance (GI) and IR as evident from the impaired glucose tolerance test, and reduced expression of adipose and hepatic insulin receptor beta (IRβ) and adipose tissue GLUT4. Treatment with SIF reversed the ovariectomy induced GI and IR. On the other hand, all these metabolic changes were further augmented when ovariectomy was followed by a high fat diet, and these changes were also reversed by SIF. Taken together, these findings emphasized the antioxidant property and anti-diabetic effects of soy isoflavones suggesting the use of this natural phytoestrogen as a strategy for relieving oxidative stress and insulin resistance in postmenopausal women.

Turner syndrome and associated problems in Turkish children: a multicenter study

OBJECTIVE

Turner syndrome (TS) is a chromosomal disorder caused by complete or partial X chromosome monosomy that manifests various clinical features depending on the karyotype and on the genetic background of affected girls. This study aimed to systematically investigate the key clinical features of TS in relationship to karyotype in a large pediatric Turkish patient population.

METHODS

Our retrospective study included 842 karyotype-proven TS patients aged 0-18 years who were evaluated in 35 different centers in Turkey in the years 2013-2014.

RESULTS

The most common karyotype was 45,X (50.7%), followed by 45,X/46,XX (10.8%), 46,X,i(Xq) (10.1%) and 45,X/46,X,i(Xq) (9.5%). Mean age at diagnosis was 10.2±4.4 years. The most common presenting complaints were short stature and delayed puberty. Among patients diagnosed before age one year, the ratio of karyotype 45,X was significantly higher than that of other karyotype groups. Cardiac defects (bicuspid aortic valve, coarctation of the aorta and aortic stenosis) were the most common congenital anomalies, occurring in 25% of the TS cases. This was followed by urinary system anomalies (horseshoe kidney, double collector duct system and renal rotation) detected in 16.3%. Hashimoto's thyroiditis was found in 11.1% of patients, gastrointestinal abnormalities in 8.9%, ear nose and throat problems in 22.6%, dermatologic problems in 21.8% and osteoporosis in 15.3%. Learning difficulties and/or psychosocial problems were encountered in 39.1%. Insulin resistance and impaired fasting glucose were detected in 3.4% and 2.2%, respectively. Dyslipidemia prevalence was 11.4%.

CONCLUSION

This comprehensive study systematically evaluated the largest group of karyotype-proven TS girls to date. The karyotype distribution, congenital anomaly and comorbidity profile closely parallel that from other countries and support the need for close medical surveillance of these complex patients throughout their lifespan.

An unusual occurrence of hepatic granulomas and secondary sitosterolemia in turner syndrome

Although abnormal liver function tests occur in 50–80% of cases with Turner syndrome, there are no previous reports of overt hepatic disease or hepatic granulomas associated with Turner's syndrome. We report three cases of Turner syndrome associated with hepatic granulomas with a wide range of liver dysfunction. Of the three patients, first patient underwent liver transplantation; second patient remained stable on immunosuppressants; and third patient died from complications of decompensated liver cirrhosis as she declined liver transplantation due to multiple comorbidities. One patient had sitosterolemia, a rare inherited autosomal recessive disorder of cholesterol metabolism, after she ingested β-sitosterol supplement and had worsening liver function tests and lipid panel. She had remarkably abnormal lipid panel that responded to ezetimibe and by stopping the β-sitosterol supplement.

The proportion of diploid 46,XX cells increases with time in women with Turner syndrome--a 10-year follow-up study

In the normal population, loss of one of the sex chromosomes leading to monosomy (45,X) is a part of the aging process. In Turner syndrome (TS), the classic karyotype 45,X is found in up to 50% at birth, and others have a second cell line; mosaicism. The aim was to study if the chromosomal pattern in TS women changes over time. Fluorescence in situ hybridization was performed on buccal smear cells obtained twice, 10 years apart, from 42 women with TS aged 26-66 years (mean±standard deviation: 42.0±11.6). DNA probes specific for chromosomes X (DXZ1) and Y (DYZ3) were used and >100 cells were analyzed/patient. Nineteen women had monosomy (45,X) (<10% 46,XX), nine had 45,X/46,XX mosaicism, and 14 had iso, ring, or a marker chromosome at baseline. At 10 years, the percentage of diploid cells had increased in 29 of 42 women (69%), with an average increase of 5.7±13.0%. There was a positive correlation between age and % change in diploid 46,XX or 46,XY cells (r=0.38, p=0.023). This new finding might have relevance for the life expectancy in TS.

Bone status in genetic syndromes: a review

More and more data seem to indicate the presence of an increasing number of syndromes and genetic diseases characterized by impaired bone mass and quality. Meanwhile, the improvement of etiopathogenetic knowledge and the employment of more adequate treatments have generated a significant increase in survival related to these syndromes and diseases. It is thus important to identify and treat bone impairment in these patients in order to assure a better quality of life. This review provides an updated overview of bone pathophysiology and characteristics in patients with Down, Turner, Klinefelter, Marfan, Williams, Prader-Willi, Noonan, and 22q11 deletions syndrome. In addition, some options for the treatment of the bone status impairment in these patients will be briefly discussed.

Pubertal timing, bone acquisition, and risk of fracture throughout life

Pubertal maturation plays a fundamental role in bone acquisition. In retrospective epidemiological surveys in pre- and postmenopausal women, relatively later menarcheal age was associated with low bone mineral mass and increased risk of osteoporotic fracture. This association was usually ascribed to shorter time exposure to estrogen from the onset of pubertal maturation to peak bone mass attainment. Recent prospective studies in healthy children and adolescents do not corroborate the limited estrogen exposure hypothesis. In prepubertal girls who will experience later menarche, a reduced bone mineral density was observed before the onset of pubertal maturation, with no further accumulated deficit until peak bone mass attainment. In young adulthood, later menarche is associated with impaired microstructural bone components and reduced mechanical resistance. This intrinsic bone deficit can explain the fact that later menarche increases fracture risk during childhood and adolescence. In healthy individuals, both pubertal timing and bone development share several similar characteristics including wide physiological variability and strong effect of heritable factors but moderate influence of environmental determinants such as nutrition and physical activity. Several conditions modify pubertal timing and bone acquisition, a certain number of them acting in concert on both traits. Taken together, these facts should prompt the search for common genetic regulators of pubertal timing and bone acquisition. It should also open epigenetic investigation avenues to pinpoint which environmental exposure in fetal and infancy life, such as vitamin D, calcium, and/or protein supplies, influences both pubertal timing and bone acquisition.

Amniotic fluid RNA gene expression profiling provides insights into the phenotype of Turner syndrome

Turner syndrome is a sex chromosome aneuploidy with characteristic malformations. Amniotic fluid, a complex biological material, could contribute to the understanding of Turner syndrome pathogenesis. In this pilot study, global gene expression analysis of cell-free RNA in amniotic fluid supernatant was utilized to identify specific genes/organ systems that may play a role in Turner syndrome pathophysiology. Cell-free RNA from amniotic fluid of five mid-trimester Turner syndrome fetuses and five euploid female fetuses matched for gestational age was extracted, amplified, and hybridized onto Affymetrix(®) U133 Plus 2.0 arrays. Significantly differentially regulated genes were identified using paired t tests. Biological interpretation was performed using Ingenuity Pathway Analysis and BioGPS gene expression atlas. There were 470 statistically significantly differentially expressed genes identified. They were widely distributed across the genome. XIST was significantly down-regulated (p < 0.0001); SHOX was not differentially expressed. One of the most highly represented organ systems was the hematologic/immune system, distinguishing the Turner syndrome transcriptome from other aneuploidies we previously studied. Manual curation of the differentially expressed gene list identified genes of possible pathologic significance, including NFATC3, IGFBP5, and LDLR. Transcriptomic differences in the amniotic fluid of Turner syndrome fetuses are due to genome-wide dysregulation. The hematologic/immune system differences may play a role in early-onset autoimmune dysfunction. Other genes identified with possible pathologic significance are associated with cardiac and skeletal systems, which are known to be affected in females with Turner syndrome. The discovery-driven approach described here may be useful in elucidating novel mechanisms of disease in Turner syndrome.

Current concepts surrounding bone health and osteoporosis in Turner syndrome

Although Turner syndrome is the most common chromosomal disorder in women, a great deal remains to be understood in terms of optimal patient care, particularly as it relates to bone health. These women are known to be at risk for osteoporosis and fracture later in life as a result of a multitude of risk factors. While estrogen replacement and childhood growth hormone treatment are now considered standard of care, little is known of the role of further interventions to prevent and treat osteoporosis in these women. This review aims to highlight the specifics of bone health in Turner syndrome. We explore the bone diagnostic modalities and therapeutic interventions available and their role in the coming years of bone health management in this unique population.

Pregnancy and Cardiovascular Risk for Women with Turner Syndrome

Most women with Turner syndrome (TS) are infertile due to primary ovarian failure. However, approximately 5% experience spontaneous pregnancy, and recently, more women with TS have used assisted reproductive technology with donated oocytes (ART-OD) to become pregnant. The first generation of Turner patients undergoing ART-OD demonstrated a high rate of fatal aortic dissection in late pregnancy or postpartum. More recent observations, particularly from Nordic countries, suggest a lesser risk of dissection, but confirm a high rate of pre-eclampsia in ART-OD pregnancies. This article reviews publications since 2000 concerning maternal outcomes for pregnancies in women with TS to determine if specific risk factors such as type of pregnancy, age, or presence of underlying congenital cardiovascular disease may identify women at special risk.

Estrogen replacement therapy regulation of energy metabolism in female mouse hypothalamus

Estrogens play an important role in the regulation of energy homeostasis in female mammals and a reduced ovarian function, due to natural aging or surgery, is associated with body weight increase and fat redistribution. This disruption of energy homeostasis may constitute a trigger for several pathologies known to be associated with climacterium; however, so far, limited attention has been devoted to the ability of estrogen replacement therapies (ERT) to reinstate the balanced energy metabolism characteristic of cycling female mammals. The purpose of the present study was to compare the efficacy of selected ERTs in reversing the ovariectomy-induced gain in body weight. To this aim female ERE-Luc mice were ovariectomized and, after 3 weeks, treated per os for 21 days with: conjugated estrogens, two selective estrogen receptor modulators (bazedoxifene and raloxifene), and the combination of bazedoxifene plus conjugated estrogens (tissue-selective estrogen complex, TSEC). The study shows that the therapy based on TSEC was the most efficacious in reducing the body weight accrued by ovariectomy (OVX). In addition, by means of in vivo imaging, the TSEC treatment was shown to increase estrogen receptor (ER) transcriptional activity selectively in the arcuate nucleus, which is a key area for the control of energy homeostasis. Finally, quantitative analysis of the mRNAs encoding orexigenic and anorexigenic peptides indicated that following ERT with TSEC there was a significant change in Agrp, NPY, and Kiss-1 mRNA accumulation in the whole hypothalamus. Considering that prior studies showed that ERT with TSEC was able to mimic the rhythm of ER oscillatory activity during the reproductive cycle and that such fluctuations were relevant for energy metabolism, the present observations further point to the ER tetradian oscillation as an important component of the ER signaling necessary for the full hormone action and therefore for an efficacious ERT.

Hearing loss among patients with Turner's syndrome: literature review1

Introduction

Turner's syndrome (TS) is caused by a partial or total deletion of an X chromosome, occurring in 1:2,000 to 1:5,000 live born females. Hearing loss is one of its major clinical manifestations. However, there are few studies investigating this problem.

Objectives

To review the current knowledge regarding the epidemiology, etiology, clinical manifestations and diagnosis of hearing impairment in patients with TS.

Methods

A bibliographic search was performed in the Medline and Lilacs databanks (1980-2012) to identify the main papers associating Turner's syndrome, hearing impairment and its clinical outcomes.

Conclusions

Recurrent otitis media, dysfunction of the Eustachian tube, conductive hearing loss during infancy and sensorineural hearing loss in adolescence are the audiologic disorders more common in ST. The karyotype appears to be important in the hearing loss, with studies demonstrating an increased prevalence in patients with monosomy 45,X or isochromosome 46,i(Xq). Morphologic studies of the cochlea are necessary to help out in the clarifying the etiology of the sensorineural hearing loss.

Comparative cytogenetic analysis in two tissues with different lineage in Turner's syndrome patients: correlation with phenotype

OBJECTIVE

To analyze karyotype of Turner's syndrome (TS) patients in two tissues of different lineage, and to correlate them with phenotype.

STUDY DESIGN

An observational study was designed at the Gynaecological Endocrinology Unit of Hospital Clinic in Barcelona. Patients diagnosed with TS by blood karyotype were included, between 20 and 50 years of age. A new 50-cell count blood karyotype and a urethral cell karyotype from urine samples were performed. Data on some TS-related comorbidities were collected.

RESULTS

Twenty-seven TS patients were included. Urine cultures of 12 patients were contaminated by microorganisms. With 50-cell count blood karyotype, three cryptic mosaicisms were found. Six patients with mosaicism in blood karyotype showed pure monosomy in urine karyotype. Correlations exist between blood karyotype and phenotype where spontaneous menarche, height, dysmorphology, congenital malformations and hypothyroidism are concerned, whereas they did not appear in urine analysis.

CONCLUSIONS

Karyotyping T-lymphocytes in blood samples is the gold standard technique. 50-cell count may be considered if TS or ovarian failure is suspected, in order to detect cryptic mosaicisms. Urethral cell culture from urine samples presents technical difficulties and some limitations, due to the easier lost of abnormal X-chromosome. A partial correlation between blood karyotype and phenotype exists.

The etiology of short stature affects the clinical outcome of lower limb lengthening using external fixation. A systematic review of 18 trials involving 547 patients

BACKGROUND AND PURPOSE

Distraction osteogenesis (DO) has been used to gain height in short statured individuals. However, there have been no studies comparing the clinical outcome of limb lengthening based on the etiology of the short stature. We assessed whether different underlying diagnoses are associated with varied clinical outcomes in these patients.

METHODS

We performed a systematic review of the literature pertaining to lower limb lengthening using external fixation for short stature. Clinical outcomes including amount of lengthening, healing index (HI), and complications based on the underlying diagnosis for the short stature were documented.

RESULTS

18 clinical studies were included, with 547 patients who underwent 1,581 lower limb segment lengthening procedures. Mean follow-up was 4.3 years. The average age at lengthening was less for individuals with achondroplasia/hypochondroplasia (A/H) (14.5 years) than for those with Turner's syndrome (TS) (18.2 years) or with constitutional short stature (CSS) (21.7 years). Mean height gained was greater in patients with A/H (9.5 cm) than in those with TS (7.7 cm) or CSS (6.1 cm) group. The HI was better in A/H (30.8 days/cm) and CSS (32 days/cm) than in TS (45.1 days/cm). The reported complication rate per segment was lower for A/H (0.68) and TS (0.71) than for CSS (1.06).

INTERPRETATION

Patients with A/H tolerated larger amounts of lengthening with fewer complications than those with other diagnoses.

Turner's syndrome: challenges of late diagnosis

Girls and women with Turner's syndrome who come to medical attention older than 12 years present a challenge of medical management. Puberty is already delayed and some compromises have to be made in adjusting the timing of artificially induced puberty to optimise overall outcome with respect to stature, secondary sex characteristics, and psychosocial endpoints. Additionally, individuals who present with primary amenorrhoea to adult services might miss the opportunity for effective growth hormone treatment. Further, induction of puberty regimens lack an evidence base or even clear guidelines for the timing and dose of oestrogen replacement. We have searched the scientific literature to inform management of Turner's syndrome.

Spuriously elevated free thyroxine associated with autoantibodies, a result of laboratory methodology: case report and literature review

OBJECTIVE

We describe a case of spurious hyperthyroxinemia secondary to thyroid hormone autoantibodies (THAAbs) in a clinically euthyroid patient with Turner mosaic syndrome.

METHODS

Several commonly available laboratory-based approaches were used, which indicated a disproportionate elevation of free thyroxine (T4) and ultimately led to the diagnosis of THAAbs. A literature review was undertaken to examine the clinical and laboratory associations of THAAbs.

RESULTS

The free T4 result of the patient was highly discrepant when measured using an Advia Centaur platform (5.89 ng/dL) as compared with the Vitros 5600 and DxI 800 platforms (1.03 and 0.74 ng/dL, respectively). Polyethylene glycol precipitation of the patient's sample showed reduced free T4 recovery (26%), suggesting the presence of a high-molecular-weight interfering substance. Rheumatoid factor and heterophile blocking tube studies were negative. These results suggested a presumptive diagnosis of THAAbs. Direct detection of THAAbs using a radiobinding method confirmed the diagnosis. A review of the literature showed that THAAbs are prevalent among patients with (autoimmune and nonautoimmune) thyroid disorders and nonthyroid autoimmune disorders but rarely cause spurious measurements. Possible pathogenesis includes molecular mimicry, exposure of the antigenic surfaces of iodinated thyroglobulin molecules to B lymphocytes in injurious or inflammatory conditions involving the thyroid gland. Free thyroid hormone methods using one-step analog and labeled antibody designs are prone to falsely high measurements, whereas two-step analog designs may produce spuriously low results.

CONCLUSION

THAAbs are an underrecognized cause of laboratory interference that is best approached by joint clinical-laboratory efforts. The routine laboratory techniques described above can suggest preliminary diagnosis of this rare entity.

Energy metabolism and fertility: a balance preserved for female health

In female animals, energy metabolism and fertility are tightly connected, and reciprocally regulated. However, the relative contributions of metabolic and reproductive pathways have changed over the course of evolution. In oviparous animals, metabolic factors take precedence over fertility, enabling egg production to be inhibited in a nutritionally poor environment. By contrast, in placental mammals, the opposite occurs: the need to feed a developing embryo and neonate forces metabolic pathways to adapt to these reproductive needs. This physiological necessity explains why in female mammals alterations of gonadal activity, including age-dependent cessation of ovarian functions, are associated with a disruption of metabolic homeostasis and consequent inflammatory reactions that trigger the onset of metabolic, cardiovascular, skeletal and neural pathologies. This Review discusses how metabolic homeostasis and reproductive functions interact to optimize female fertility and explains the pathogenic mechanisms underlying the disordered energy metabolism associated with human ovarian dysfunction owing to menopause, polycystic ovary syndrome and Turner syndrome. Finally, this article highlights how hormone replacement therapy might aid the restoration of metabolic homeostasis in women with ovarian dysfunction.

Evaluation of cardiovascular anomalies in patients with asymptomatic turner syndrome using multidetector computed tomography

Turner syndrome is well known to be associated with significant cardiovascular abnormalities. This paper studied the incidence of cardiovascular abnormalities in asymptomatic adolescent patients with Turner syndrome using multidetector computed tomography (MDCT) instead of echocardiography. Twenty subjects diagnosed with Turner syndrome who had no cardiac symptoms were included. Blood pressure and electrocardiography (ECG) was checked. Cardiovascular abnormalities were checked by MDCT. According to the ECG results, 11 had a prolonged QTc interval, 5 had a posterior fascicular block, 3 had a ventricular conduction disorder. MDCT revealed vascular abnormalities in 13 patients (65%). Three patients had an aberrant right subclavian artery, 2 had dilatation of left subclavian artery, and others had an aortic root dilatation, aortic diverticulum, and abnormal left vertebral artery. As for venous abnormalities, 3 patients had partial anomalous pulmonary venous return and 2 had a persistent left superior vena cava. This study found cardiovascular abnormalities in 65% of asymptomatic Turner syndrome patients using MDCT. Even though, there are no cardiac symptoms in Turner syndrome patients, a complete evaluation of the heart with echocardiography or MDCT at transition period to adults must be performed.

Long QT interval in Turner syndrome--a high prevalence of LQTS gene mutations

Objectives

QT-interval prolongation of unknown aetiology is common in Turner syndrome. This study set out to explore the presence of known long QT mutations in Turner syndrome and to examine the corrected QT-interval (QTc) over time and relate the findings to the Turner syndrome phenotype.

Methods

Adult women with Turner syndrome (n = 88) were examined thrice and 68 age-matched healthy controls were examined once. QTc was measured by one blinded reader (intra-reader variability: 0.7%), and adjusted for influence of heart rate by Bazett’s (bQTc) and Hodges’s formula (hQTc). The prevalence of mutations in genes related to Long QT syndrome was determined in women with Turner syndrome and a QTc >432.0 milliseconds (ms). Echocardiographic assessment of aortic valve morphology, 24-hour blood pressures and blood samples were done.

Results

The mean hQTc in women with Turner syndrome (414.0±25.5 ms) compared to controls (390.4±17.8 ms) was prolonged (p<0.001) and did not change over time (416.9±22.6 vs. 415.6±25.5 ms; p = 0.4). 45,X karyotype was associated with increased hQTc prolongation compared to other Turner syndrome karyotypes (418.2±24.8 vs. 407.6±25.5 ms; p = 0.055). In women with Turner syndrome and a bQTc >432 ms, 7 had mutations in major Long QT syndrome genes (SCN5A and KCNH2) and one in a minor Long QT syndrome gene (KCNE2).

Conclusion

There is a high prevalence of mutations in the major LQTS genes in women with TS and prolonged QTc. It remains to be settled, whether these findings are related to the unexplained excess mortality in Turner women.

Clinical Trial Registration

NCT00624949. https://register.clinicaltrials.gov/prs/app/action/SelectProtocol/sid/S0001FLI/selectaction/View/ts/3/uid/U000099E.

Turner syndrome patients' ultrasound profile

OBJECTIVE

Evaluate the uterus and ovary by ultrasonography, considering the genotype, pubertal development and hormonal levels.

MATERIALS AND METHODS

Cross-sectional study of 53 (7-53 years old) patients with Turner syndrome considering pubertal development by Tanner stage, puberty induced or not and the ultrasound examination.

RESULTS

The patients were 10 prepubertal and 43 with pubertal signs. Uterus was found adequate in 12 (57.1%) patients and all had spontaneous puberty. Hypoplasic uterus was found in all prepubertal patients and in 28 (52.8%) patients pubescent. The ovaries were visualized bilaterally in 32 (60%) patients and unilaterally in 15 (27.7%). Ovaries were appropriate bilaterally in eight (15.1%). In pubertal patients, the average volume being significantly higher in those with spontaneous puberty (p = 0.04 and 0.03, respectively). We found no significant difference in uterine volume, when considered estrogen route and karyotype.

CONCLUSION

The ultrasonographic pattern in patients with spontaneous puberty without secondary failure was appropriate. The karyotype and the route estrogen therapy were not related to the standard of ultrasound study of the uterus and ovary.

Individualised vs fixed dose of oral 17β-oestradiol for induction of puberty in girls with Turner syndrome: an open-randomised parallel trial

CONTEXT

Oestrogen induction of pubertal changes in Turner girls may reinforce their psychological well-being and may also optimise final height; however, oestrogen type, dose, and route are not well established.

OBJECTIVE

To induce normal pubertal development in Turner girls and ovarian insufficiency with oral 17β-oestradiol (E(2)), either as individualised dose (ID) or as fixed dose (FD), and to determine whether growth is affected.

DESIGN

Open-label randomised, parallel groups, multicentre clinical trial in 48 GH-treated Turner girls. Oral E(2) was given in tablets, either as an ID of 5-15 μg/kg per day during 2 years or as a FD of 0.2 mg daily during the first year followed by 0.5 mg daily during the second year. Main outcome measures were the event of attaining a Tanner breast staging ≥4 (primary), FSH, and auxological variables (secondary).

RESULTS

Shorter median time to Tanner staging ≥ B4 in the FD group (733 days) compared with the ID group (818 days) (P=0.046). Higher proportion of girls with Tanner staging ≥ B4 (65%) in the FD group compared with the ID group (42%) (P=0.068). Bone age did not show inadequate acceleration and adult height prediction was maintained in both groups. No oestrogen-related adverse events were reported.

CONCLUSIONS

Two-year treatment with oral E(2) can progressively induce normal pubertal development in Turner syndrome. Low-dose oral E(2) given as a FD produces a satisfactory pubertal development not inferior to ID. Treatment was well tolerated and did not interfere with the growth-promoting effect of GH.

Cardiovascular phenotype in Turner syndrome--integrating cardiology, genetics, and endocrinology

Cardiovascular disease is emerging as a cardinal trait of Turner syndrome, being responsible for half of the 3-fold excess mortality. Turner syndrome has been proposed as an independent risk marker for cardiovascular disease that manifests as congenital heart disease, aortic dilation and dissection, valvular heart disease, hypertension, thromboembolism, myocardial infarction, and stroke. Risk stratification is unfortunately not straightforward because risk markers derived from the general population inadequately identify the subset of females with Turner syndrome who will suffer events. A high prevalence of endocrine disorders adds to the complexity, exacerbating cardiovascular prognosis. Mounting knowledge about the prevalence and interplay of cardiovascular and endocrine disease in Turner syndrome is paralleled by improved understanding of the genetics of the X-chromosome in both normal health and disease. At present in Turner syndrome, this is most advanced for the SHOX gene, which partly explains the growth deficit. This review provides an up-to-date condensation of current state-of-the-art knowledge in Turner syndrome, the main focus being cardiovascular morbidity and mortality. The aim is to provide insight into pathogenesis of Turner syndrome with perspectives to advances in the understanding of genetics of the X-chromosome. The review also incorporates important endocrine features, in order to comprehensively explain the cardiovascular phenotype and to highlight how raised attention to endocrinology and genetics is important in the identification and modification of cardiovascular risk.

Management of Turner's syndrome in adult life: case-series and systematic review

OBJECTIVE

To assess the symptoms and outcomes of clinical management in adult patients with Turner's Syndrome.

DESIGN

Retrospective case-series and systematic review of the literature.

SETTING

Gynaecological Endocrinology Unit in a teaching hospital.

PATIENTS

Patients followed in the Gynaecological Endocrinology Unit.

INTERVENTIONS

Review of medical records and a computer search via several databases to identify journals relevant to the subject were performed.

MAIN OUTCOME MEASURES

Final height, weight, previous treatments with growth hormone, cardiac or renal malformations, metabolic profile, and additional treatment for osteoporosis.

RESULTS

Thirty-one patients were analysed. Differences in final height were found between groups with monosomy and other karyotypes. Four patients bore congenital cardiac malformations, and six, renal congenital malformations. Nine patients had a previous diagnosis of hypercholesterolemia. The most abnormal hepatic parameter was GGT, with fifteen patients having values over the normality limit. Ten patients were receiving treatment for osteopenia or osteoporosis.

CONCLUSIONS

This case-series provides recommendations for the management of adult patients with Turner's syndrome and insight into the different medical complaints of this syndrome. A link between karyotypes and clinical features suggests a novel hypothesis to explain the different phenotypes and clinical abnormalities of these patients.

Cornelia de Lange syndrome with NIPBL mutation and mosaic Turner syndrome in the same individual

Background

Cornelia de Lange syndrome (CdLS) is a dominantly inherited disorder characterized by facial dysmorphism, growth and cognitive impairment, limb malformations and multiple organ involvement. Mutations in NIPBL gene account for about 60% of patients with CdLS. This gene encodes a key regulator of the Cohesin complex, which controls sister chromatid segregation during both mitosis and meiosis. Turner syndrome (TS) results from the partial or complete absence of one of the X chromosomes, usually associated with congenital lymphedema, short stature, and gonadal dysgenesis.

Case presentation

Here we report a four-year-old female with CdLS due to a frameshift mutation in the NIPBL gene (c.1445_1448delGAGA), who also had a tissue-specific mosaic 45,X/46,XX karyotype. The patient showed a severe form of CdLS with craniofacial dysmorphism, pre- and post-natal growth delay, cardiovascular abnormalities, hirsutism and severe psychomotor retardation with behavioural problems. She also presented with minor clinical features consistent with TS, including peripheral lymphedema and webbed neck. The NIPBL mutation was present in the two tissues analysed from different embryonic origins (peripheral blood lymphocytes and oral mucosa epithelial cells). However, the percentage of cells with monosomy X was low and variable in tissues. These findings indicate that, ontogenically, the NIPBL mutation may have appeared before the mosaic monosomy X.

Conclusions

The coexistence in several patients of these two rare disorders raises the issue of whether there is indeed a cause-effect association. The detailed clinical descriptions indicate predominant CdLS phenotype, although additional TS manifestations may appear in adolescence.

Prosthodontic treatment and medical considerations for a patient with Turner syndrome: a clinical report

This clinical report describes a multidisciplinary approach in the rehabilitation of a 23-year-old Caucasian woman affected with Turner's syndrome and subsequently diagnosed with T4 Giant cell reparative granuloma of the right maxillary sinus. The surgical treatment included a maxillectomy and infratemporal fossa dissection followed by a free fibula palatal reconstruction, fibula bone graft of the orbital floor, dental implant placement, and prosthodontic rehabilitation. Prosthodontic planning and treatment considerations in an adult patient with Turner Syndrome are discussed.

C677T and A1298C polymorphisms of MTHFR gene and their relation to homocysteine levels in Turner syndrome

AIMS

To determine the frequency of C677T and A1298C polymorphisms of the MTHFR gene and correlate them with homocysteine serum levels in patients with Turner syndrome (TS) and controls.

METHODS

This case-control study included 78 women with TS and a control group of 372 healthy individuals without personal or family history of cardiovascular disease and cancer. C677T (rs1801133) and A1298C (rs1801131) polymorphisms were detected by polymerase chain reaction-restriction fragment-length polymorphism and the TaqMan system, respectively. Homocysteine serum levels were determined by high-performance liquid chromatography. The results were analyzed statistically, and p<0.05 was considered to represent a significant difference.

RESULTS

The homocysteine levels change was 13.9+3.3 nM in patients with TS and 8.8+3.2 nM in the control group. No significant difference between groups was found (p=0.348). Single-marker analysis revealed no association between MTHFR C677T polymorphism and TS when genotype (p=0.063) or allelic (p=0.277) distribution was considered. Regarding MTHFR A1298C polymorphism, a statistical difference was found between the TS group and the control group, for both genotype (p<0.0001) and allele (p<0.0001) distribution. Haplotype analysis of 2 MTHFR polymorphisms identified 2 haplotypes-CC and TC-associated with TS (p<0.001 and p=0.0165, respectively). However, homocysteine levels were not higher in patients with haplotype risk.

CONCLUSION

The results suggest that the C677T and A1298C polymorphisms of the MTHFR gene are not related to homocysteine levels in Brazilian patients with TS, despite the differential distribution of the mutated allele C (A1298C) in these patients. Further studies are needed to investigate the possible genetic interaction with homocysteine levels in TS.

Coagulation and fibrinolytic disturbances are related to carotid intima thickness and arterial blood pressure in Turner syndrome

OBJECTIVE

Turner syndrome (TS) is characterized by growth retardation, hypogonadism and a high risk of cardiovascular complications and atherosclerosis; case reports suggest that thrombo-embolic complications may be present.

DESIGN

Cross-sectional study.

PATIENTS

Sixty women with TS.

MEASUREMENTS

We characterized the activities of the haemostatic system, elucidated by the assessment of a panel of clotting factors and thrombosis risk factors and related these findings to carotid intima thickness (CIMT) and blood pressure.

RESULTS

Most (81%) received hormone replacement therapy. The medians of all measured factors and inflammatory parameters were not different from normative data, but many cases displayed values of C-reactive protein (CRP) (40%), fibrinogen (15%), fibrin D-dimer (15%), factor VIII (25%), von Willebrand factor (vWF) (15%), cholesterol and liver parameters that were greater than normative limits. CRP, fibrinogen, vWF, factor VIII and liver parameters were highly and positively correlated. Haemostatic variables were positively related to both CIMT and blood pressure. The Factor V Leiden G1691A gene polymorphism heterozygosity was detected in 12·5%.

CONCLUSION

We describe a significant proportion of individual TS females having high levels of vWF, factor VIII, fibrinogen and CRP (15-40%) and an increased frequency of the Leiden mutation, with important associations with CIMT and blood pressure, suggesting that a subset of TS may have an unfavourable haemostatic balance, which may contribute to the increased risk of premature ischaemic heart disease and possibly increase the risk of deep venous and portal vein thrombosis.