Epidemiological, endocrine and metabolic features in Turner syndrome

Sex hormone replacement in Turner syndrome

The cardinal features of Turner syndrome (TS) are short stature, congenital abnormalities, infertility due to gonadal dysgenesis, with sex hormone insufficiency ensuing from premature ovarian failure, which is involved in lack of proper development of secondary sex characteristics and the frequent osteoporosis seen in Turner syndrome. But sex hormone insufficiency is also involved in the increased cardiovascular risk, state of physical fitness, insulin resistance, body composition, and may play a role in the increased incidence of autoimmunity. Severe morbidity and mortality affects females with Turner syndrome. Recent research emphasizes the need for proper sex hormone replacement therapy (HRT) during the entire lifespan of females with TS and new hypotheses concerning estrogen receptors, genetics and the timing of HRT offers valuable new information. In this review, we will discuss the effects of estrogen and androgen insufficiency as well as the effects of sex HRT on morbidity and mortality with special emphasis on evidence based research and areas needing further studies.

Anti-Mullerian hormone as a predictor of follicular reserve in ovarian insufficiency: special emphasis on FSH-resistant ovaries

BACKGROUND

Anti-Müllerian hormone (AMH) is secreted by ovarian granulosa cells and its serum levels reflect ovarian follicle reserve. The main objective of this study was to test the use of AMH assay in identifying women with primary amenorrhea (PA) and existing follicles and to study follicle phase dependent AMH secretion.

METHODS

Serum levels of AMH were measured in subjects with FSH-resistant ovaries (FSHRO, n= 12), primary ovarian insufficiency (POI) with PA (n= 11) or secondary amenorrhea (SA n= 20) of unknown etiology, and controls (n= 23), and in Turner syndrome (TS) [45,X (n= 18), mosaicism (n= 7), structural X chromosome abnormalities (SCA, n= 10)], and healthy controls (n= 34).

RESULTS

Serum levels of AMH in women with FSHRO were comparable with those in control women (2.76 ± 2.37 versus 3.77 ± 2.36 ng/ml) and significantly higher than in women with PA (0.05 ± 0.04 ng/ml; P < 0.001) or SA of unknown origin (0.12 ± 0.20 ng/ml; P < 0.001). TS girls/women with 45,X or SCA had low serum AMH levels (0.13 ± 0.09 and 0.27 ± 0.19 ng/ml) compared with their controls (3.34 ± 2.23 ng/ml) or subjects with mosaicism (2.33 ± 2.81 ng/ml). AMH expression was detected in granulosa cells of women with FSHRO but not in any of the 45,X fetal ovarian specimens.

CONCLUSIONS

A serum AMH assay could be used to identify patients with decreasing ovarian reserves and POI. Moreover, our results support the notion that AMH is secreted mainly by small non-selected follicles, since follicular granulosa cells were AMH-positive and serum AMH levels were normal/low normal in women with FSHRO, who lack follicle development beyond the small antral stage.

Autoimmunity and Turner's syndrome

Turner Syndrome (TS) is a common genetic disorder, affecting female individuals, resulting from the partial or complete absence of one sex chromosome, and occurring in approximately 50 per 100,000 liveborn girls. TS is associated with reduced adult height and with gonadal dysgenesis, leading to insufficient circulating levels of female sex steroids and to infertility. Morbidity and mortality are increased in TS but average intellectual performance is within the normal range. TS is closely associated to the presence of autoantibodies and autoimmune diseases (AID), especially autoimmune thyroiditis and inflammatory bowel disease. Despite the fact that the strong association between TS and AID is well known and has been widely studied, the underlying immunopathogenic mechanism remains partially unexplained. Recent studies have displayed how TS patients do not show an excess of immunogenic risk markers. This is evocative for a higher responsibility of X-chromosome abnormalities in the development of AID, and particularly of X-genes involved in immune response. For instance, the long arm of the X chromosome hosts a MHC-locus, so the loss of that region may lead to a deficiency in immune regulation. Currently no firm guidelines for diagnosis exist. In conclusion, TS is a condition associated with a number of autoimmune manifestations. Individuals with TS need life-long medical attention. As a consequence of these findings, early diagnosis and regular screening for potential associated autoimmune conditions are essential in the medical follow-up of TS patients.

Reduced sebum production in Turner syndrome: a study of twenty-two patients

Turner's syndrome (TS) is a genetic disorder caused by numeric and/or structural abnormalities of the X chromosome. In a previous study it was observed that acne is less frequent in TS than in the general population. Since the onset of acne in pre-pubertal or pubertal age is related to sebum production, this study evaluates sebum secretion in TS patients, comparing the results with those of a control group of age-matched healthy female subjects. A total of 22 patients affected by TS (mean age 26.56±7.89 years) and a control group of 23 age-matched healthy females were studied. Sebum production was measured using a Sebumeter SM810. Mean sebum secretion in TS subjects was significantly lower than in the control group (81.35±66.44 UA vs 147.09±33.62 UA, p<0.001) and this significant difference was found in every facial zone. The reduction of sebum secretion may explain, using a simple and non-invasive method, the absence or the low incidence of acne in TS patients.

The influence of sex-linked genetic mechanisms on attention and impulsivity

It is now generally agreed that there are inherent sex differences in healthy individuals across a number of neurobiological domains (including brain structure, neurochemistry, and cognition). Moreover, there is a burgeoning body of evidence highlighting sex differences within neuropsychiatric populations (in terms of the rates of incidence, clinical features/progression, neurobiology and pathology). Here, we consider the extent to which attention and impulsivity are sexually dimorphic in healthy populations and the extent to which sex might modulate the expression of disorders characterised by abnormalities in attention and/or impulsivity such as attention deficit hyperactivity disorder (ADHD), autism and addiction. We then discuss general genetic mechanisms that might underlie sex differences in attention and impulsivity before focussing on specific positional and functional candidate sex-linked genes that are likely to influence these cognitive processes. Identifying novel sex-modulated molecular targets should ultimately enable us to develop more effective therapies in disorders associated with attentional/impulsive dysfunction.

Cardiovascular disease and primary ovarian insufficiency

Cardiovascular disease (CVD) is the number-one killer of women. Women with primary ovarian insufficiency (POI) may be more burdened by cardiovascular disease, such as myocardial infarction and stroke, as compared with women with normal menopause. The increased burden may be mediated by a worsening of cardiovascular risk factors, such as lipids, corresponding with the loss of ovarian function. In contrast, the increased burden may be caused by factors that precede and potentially contribute to both CVD events and ovarian decline, such as X-chromosome abnormalities and smoking. Regardless of the cause, women with POI may serve as an important population to target for CVD screening and prevention strategies. These strategies should include the use of CVD risk stratification tools to identify women that may benefit from lifestyle modification and pharmacological therapy to prevent CVD. Sex steroid therapy for the sole purpose of CVD prevention in women with POI cannot be recommended, based on a lack of evidence.

Standardized multidisciplinary evaluation yields significant previously undiagnosed morbidity in adult women with Turner syndrome

CONTEXT

Besides short stature and gonadal dysgenesis, Turner syndrome (TS) is associated with various abnormalities. Adults with TS have a reduced life expectancy, mainly related to structural abnormalities of the heart and aorta, and an increased risk of atherosclerosis.

OBJECTIVE

Our objective was to investigate the yield of an initial standardized multidisciplinary screening in adult TS patients.

DESIGN AND SETTING

This was an observational study at a multidisciplinary care unit for adult women with TS.

PARTICIPANTS

Participants were adult women with TS (n = 150). Mean age was 31.0 ± 10.4 yr, with 47% karyotype 45,X.

INTERVENTIONS

All women were consulted by an endocrinologist, a gynecologist, a cardiologist, an otorhinolaryngologist, and when indicated, a psychologist. The screening included magnetic resonance imaging of the heart and aorta, echocardiography, electrocardiogram, dual-energy x-ray absorptiometry, renal ultrasound, audiogram, and laboratory investigations according to international expert recommendations.

MAIN OUTCOME MEASURES

New diagnoses and prevalence of TS-associated morbidity were evaluated.

RESULTS

Thirty percent of patients currently lacked medical follow-up, and 15% lacked estrogen replacement therapy in the recent last years. The following disorders were newly diagnosed: bicuspid aortic valve (n = 13), coarctation of the aorta (n = 9), elongation of the transverse aortic arch (n = 27), dilation of the aorta (n = 34), osteoporosis (n = 8), osteopenia (n = 56), renal abnormalities (n = 7), subclinical hypothyroidism (n = 33), celiac disease (n = 3), glucose intolerance (n = 12), dyslipidemia (n = 52), hypertension (n = 39), and hearing loss warranting a hearing aid (n = 8). Psychological consultation was needed in 23 cases.

CONCLUSIONS

Standardized multidisciplinary evaluation of adult women with TS as advocated by expert opinion is effective and identifies significant morbidity. Girls with TS benefit from a careful transition to ongoing adult medical care.

Endotelium in Turner syndrome with capillaroscopy

OBJECTIVE: The aim of this study was to assess the endothelium function in patients with Turner syndrome using videocapillaroscopy and to compare the results with healthy control. METHODS: Subjects and controls were studied in a temperature-controlled room, 20 days after no nailfold manipulations. The capillaries were visualized by a microscope connected to a television and a computer. The test of post-occlusive reactive hyperemia was performed using a sphygmomanometer attached to the fourth left finger, 20mmHg above maximum arterial pressure during 1 minute, and the following patterns were studied: area of transverse segment, maximal post-ischemia area and time to reach maximal post-ischemia area. RESULTS: The value of measure of transverse segment projected area , the maximal postischemia area of hand nailfold capillary loops using computerized videophotometry and the time to reach maximal post ischemia area were studied in 40 patients with Turner syndrome and 26 healthy women controls of comparable age (20±7.5 versus 18±8.1 years old; p=0.57). There were differences between transverse segment area (706.8±139.1 versus 548.8±117.2; p=0.001). Maximal post-ischemia area (891.3±226.1 versus 643.5±134.3; p=0.001) and the time to reach it (10.8±4.3 versus 5.5±2.5; p=0.001) were different between patients and controls. CONCLUSIONS: Changes of capillary response to ischemia could be observed in patients with Turner syndrome using videocapillaroscopy when they were compared to a healthy control group.

Uterus and ovaries in girls and young women with Turner syndrome evaluated by ultrasound and magnetic resonance imaging

OBJECTIVE

To determine uterine and ovarian size in Turner syndrome (TS) and to compare uterine and ovarian size evaluated by transabdominal ultrasound (US) and magnetic resonance imaging (MRI) in girls with TS and two groups of controls.

DESIGN

A cross-sectional study.

PATIENTS

Forty-one girls with TS (17·0 ± 3·3 years, range 11·2-24·9 years), 50 healthy age-matched controls (16·9 ± 3·2 years, range 12·5-25·0 years) and 107 Tanner-stage-matched controls (15·0 ± 3·2 years, range 10·1-24·2).

MEASUREMENTS

Uterine and ovarian volume by US and MRI.

RESULTS

Ovaries were detected in 37% in TS by US and in 55% in TS by MRI (P = 0·1). Total ovarian volume was lower in TS compared to both groups of controls (TS vs C-US: median 1·1 ml (range 0·1-29·3) vs 11·52 ml (1·9-77·9), P = 0·001, TS vs C-MRI: 1·0 ml (0·1-34·2) vs 13·2 ml (2·4-30·1), P < 0·0005). Mean difference in total ovarian volume measured by MRI and US in patients with TS was 2·3 ± 3·8 ml (P = 0·01). Mean uterine volume by MRI was lower in TS compared to controls (29·5 ± 25·1 vs 54·3 ± 23·3 ml, P < 0·0005). Uterine volume by US was lower in TS at Tanner stage B5 compared to controls (TS vs C: 33·6 ± 18·2 vs 50·2 ± 18·0 ml, P = 0·007).

CONCLUSIONS

A larger ovarian volume was detected by MRI in TS compared to US. This finding is important with the advancements of performing ovarian biopsies for cryopreservation and later reimplantation. Mean uterine volumes by MRI and US in fully matured TS were lower compared to controls despite appropriate hormonal replacement therapy in TS.

Metabolic and cardiovascular outcomes in a group of adult patients with Turner's syndrome under hormonal replacement therapy

OBJECTIVE

Turner's syndrome (TS) is a rare genetic disorder caused by complete or partial X chromosome monosomy in a phenotypic female, and it is associated with increased morbidity and mortality for cardiovascular diseases, impaired glucose tolerance, and dyslipidemia.

SUBJECTS AND METHODS

In 30 adult TS patients under chronic hormonal replacement therapy (HRT), 17β-estradiol (E(2)), body mass index (BMI), waist circumference, fasting glucose and insulin, homeostatic model assessment (HOMA) index, serum lipids, oral glucose tolerance test (OGTT), 24 h ambulatory blood pressure monitoring (ABPM), and intima-media thickness (IMT) were evaluated and compared with those in 30 age- and sex-matched controls (CS).

RESULTS

No difference was found between TS and CS in E(2) and BMI, whereas waist circumference was higher (P<0.05) in TS (77.7±2.5 cm) than in CS (69.8±1.0 cm). Fasting glucose in TS and in CS was similar, whereas fasting insulin, HOMA index, and 2 h glucose after OGTT were higher (P<0.0005) in TS (13.2±0.8 mUI/l, 2.5±0.2, and 108.9±5.5 mg/dl respectively) than in CS (9.1±0.5 mUI/l, 1.8±0.1, and 94.5 ± 3.8 mg/dl respectively). Total cholesterol was higher (P<0.05) in TS (199.4 ± 6.6 mg/dl) than in CS (173.9±4.6 mg/dl), whereas no significant differences in high-density lipoprotein, low-density lipoprotein, and triglycerides were found between the two groups. In 13% of TS, ABPM showed arterial hypertension, whereas IMT was <0.9 mm in all TS and CS. A negative correlation between insulin levels, HOMA index, or 2 h glucose after OGTT and E(2) was present in TS.

CONCLUSIONS

Our results indicate that adult patients with TS under HRT are connoted by higher frequency of central obesity, insulin resistance, hypercholesterolemia, and hypertension.

A highly sensitive, high-throughput assay for the detection of Turner syndrome

OBJECTIVE

Turner syndrome (TS) occurs when an X-chromosome is completely or partially deleted or when X-chromosomal mosaicism is present. Girls with TS benefit from early diagnosis and treatment with GH; however, many girls with TS are not detected until after 10 yr of age, resulting in delayed evaluation and treatment.

METHODS

We developed a high-throughput test for TS, based on a quantitative method of genotyping to detect X-chromosome abnormalities. This test uses pyrosequencing to quantitate relative allele strength (RAS) from single-nucleotide polymorphisms using 18 informative single-nucleotide polymorphisms markers that span the X-chromosome and one marker for the detection of Y-chromosome material.

RESULTS

Cutoff ranges for heterozygous, homozygous, or out-of-range RAS values were established from a cohort of 496 males and females. Positive TS scoring criteria were defined as the presence of homozygosity for all 18 markers or the presence of at least one out-of-range RAS value. To determine the validity of this rapid test for TS detection, we undertook a large-scale study using DNA from 132 females without TS and 74 females with TS for whom karyotypes were available. TS was identified with 96.0% sensitivity and 97.0% specificity in this cohort. We also tested buccal swab DNA from a group of 19 females without TS and 69 females with TS. In this group, TS was identified with 97.1% sensitivity and 84.2% specificity.

CONCLUSIONS

These results demonstrate the validity of a high-throughput, pyrosequencing based test for the accurate detection of TS, providing a potential alternative to karyotype testing.

Fibroscan: a new noninvasive method for evaluation of liver dysfunction in Turner syndrome

BACKGROUND

Raised liver enzyme value is frequently detected in patients with Turner syndrome (TS), but its clinical importance is still unclear.

OBJECTIVE

To investigate the entity of liver involvement in TS and to avoid the invasiveness of liver biopsy, we planned to measure liver stiffness by transient elastography (TE).

DESIGN

Cross-sectional study.

PATIENTS AND METHODS

Twenty-five consecutive patients with TS and a chronological age ≥ 12·5 years (mean age = 21·7 years), full pubertal development and final height's achievement were enrolled and investigated by blood biochemical analyses [glucose, insulin, aspartate-aminotransferase (AST), alanine-aminotransferase (ALT), gamma-glutamil transferase (GGT), alkaline phosphatase, cholesterol, triglyceride, HDL-cholesterol], ultrasonography and TE of the liver.

RESULTS

Of 25, 7 subjects (28%) showed liver enzyme levels higher than the normal upper limit. Mean liver stiffness value in the entire study group was 4·5 ± 1·7 kPa, being significantly higher in patients with abnormal liver enzymes than in those with normal liver biochemistry (6·0 ± 2·9 vs. 4·0 ± 0·9, P < 0·05). Strong correlations were found between TE values and ALT (P < 0·005), GGT (P < 0·0001), Body mass index (P < 0·05), HOMA index (P < 0·05), HDL-cholesterol (P < 0·05) and triglycerides (P < 0·0001).

CONCLUSIONS

We can assert that (i) liver stiffness, measured by TE, strongly correlates with liver enzyme levels in patients with TS ; (ii) the increased liver stiffness in patients with TS with biochemical signs of liver dysfunction is significantly related to metabolic syndrome parameters; (iii) TE may be an useful tool to select among patients with TS with elevated liver enzymes or other metabolic risk factors, those who deserve more invasive diagnostic procedures, namely liver biopsy, for the best characterisation of liver damage.

Vitamin D receptor genotypes are associated with bone mass in patients with Turner syndrome

BACKGROUND

Turner syndrome (TS) patients present low bone mineral density (BMD) and increased fracture risk, probably due to a genetic defect aggravated by hormonal deficiency.

AIM

To study the relationship between vitamin D receptor (VDR) gene polymorphisms and BMD and bone parameters in TS patients.

METHODS

DNA from 65 TS patients and 110 controls was amplified by PCR and digested with FokI, BsmI and ApaI restrictases. Lumbar and femoral BMD were determined by DEXA and serum intact parathyroid hormone, osteocalcin and beta-CrossLaps by electrochemiluminescence.

RESULTS

Genotype distribution within the ApaI site was different in both groups: genotype Aa was more abundant in TS (63.8% vs. 41.3%; p<0.01), whereas AA predominated in controls (33.9% vs. 15.5%; p<0.01). Patients carrying genotype bb (BsmI) or ff (FokI) had lower BMD than those with other genotypes (p<0.01 and p<0.05, respectively).

CONCLUSION

BsmI and FokI polymorphic sites of VDR could be genetic determinants of BMD in TS patients.

[The inclusion of new techniques of chromosome analysis has improved the cytogenetic profile of Turner syndrome]

OBJECTIVE

To evaluate the effect of the improvement of chromosome analysis on the cytogenetic findings of Turner syndrome (TS) patients.

METHODS

Retrospective study of the results of the karyotypes of 260 patients with TS, regarding banding techniques, number of cells analyzed and results of investigation of Y-chromosome sequences. According to karyotype, divided in 45,X; sex chromosome mosaicism without Y; structural aberrations of sex chromosomes with or without mosaicism; sex chromosome mosaicism with Y.

RESULTS

45,X was the most frequent karyotype (108), followed by structural aberrations (88) and mosaics (58 without Y and 6 with Y). Introduction of banding techniques and increase in the number of cells analyzed resulted in progressive decrease of 45,X karyotype and increase of structural aberrations. The study of Y-chromosome sequences was performed in 96 cases of which 10 resulted positive.

CONCLUSIONS

Improvement of chromosome analysis over the years has modified the cytogenetic profile of TS.

Somatotropin in the treatment of growth hormone deficiency and Turner syndrome in pediatric patients: a review

Growth hormone (GH), also known as somatotropin, is a peptide hormone that is synthesized and secreted by the somatotrophs of the anterior pituitary gland. The main action of GH is to stimulate linear growth in children; however, it also fosters a healthy body composition by increasing muscle and reducing fat mass, maintains normal blood glucose levels, and promotes a favorable lipid profile. This article provides an overview of the normal pathophysiology of GH production and action. We discuss the history of GH therapy and the development of the current formulation of recombinant human GH given as daily subcutaneous injections. This paper reviews two of the longest standing FDA-approved indications for GH treatment, GH deficiency and Turner syndrome. We will highlight the pathogenesis of these disorders, including presentations, presumed mechanism(s) for the associated short stature, and diagnostic criteria, with a review of stimulation test benefits and pitfalls. This review also includes current recommendations for GH therapy to help maximize final height in these children, as well as data demonstrating the efficacy and safety of GH treatment in these populations.

Health status in women with Turner syndrome: a questionnaire study on health status, education, work participation and aspects of sexual functioning

CONTEXT

Turner syndrome (TS) is a complex medical condition with specific cognitive and psychosocial characteristics and frequent medical morbidity. Few studies have investigated the influence this has on health status, education and ability to work.

OBJECTIVE

To explore health status, level of education, work participation, medical conditions, physical activity, satisfaction with life and aspects of sexual functioning in adult TS women and compare with a matched control group.

DESIGN

A questionnaire was sent to 168 adult women with TS >18 years registered in a database of Frambu Resource Centre for Rare Disorders and The TS Association in Norway. We assessed health status with Short Form 36, education with Norwegian Standard Classification of Education, and employment with The General Nordic Questionnaire. Life satisfaction was measured with LiSat-9, and questions on psychological strain during life phases were included.

RESULTS

Eighty women with TS (34.0 +/- 11.7 years) and 214 controls (32.9 +/- 10.6) responded. The TS group reported significantly more health problems and impaired health status in the two subscales "physical functioning" and "general health" (P < 0.001). Level of education and work participation was similar among TS and controls. TS moved away from their parents' home later than controls (20.4 +/- 4.0 vs. 18.7 +/- 2.1, P = 0.001). Age at sexual debut differed significantly (21.2 +/- 4.3 vs. 17.3 +/- 2.4 years, P < 0.001).

CONCLUSION

TS attains the same level of education and level of employment as controls, they report more frequent occurrence of medical conditions, but scored lower on only two subscales in the SF-36. Despite considerable medical morbidity, TS seem to cope well with life.

Discontinuation of hormone replacement therapy in young GH-treated hypopituitary women increases liver enzymes

OBJECTIVE

Hypopituitarism, often characterized by hypogonadism, is associated with central obesity, increased cardiovascular and endocrine morbidity and mortality. In Turner syndrome, which is also characterized by hypogonadism liver enzymes are often elevated, but readily suppressed by a short course of hormone replacement therapy (HRT). We investigated the effect of HRT on liver enzymes, lipid levels and measures of insulin sensitivity 26 in hypopituitary women.

DESIGN

We studied 26 hypopituitary women (age 38.8+/-11.0 (mean+/-SD years), BMI 27.4+/-5.1kg/m(2)) during HRT and 28days off therapy.

METHODS

We measured liver enzymes, fasting levels of lipids, insulin and glucose as well as adiponectin and leptin levels. Body composition was assessed by means of anthropometry and bioimpedance.

RESULTS

Alanine transaminase (ALT) and aspartate transaminase (AST) increased after discontinuation of HRT (ALT; treated: 22.3+/-11.5 vs. untreated: 27.1+/-11.1 (U/L) (P<0.02); AST; treated: 20.4+/-6.1 vs. untreated: 24.6+/-8.9 (U/L) (P<0.002)), whereas other liver function tests remained unchanged. Measures of insulin sensitivity and fasting lipids were also unaffected by HRT, whereas leptin levels decreased with cessation of HRT (leptin; treated: 23 (8-71) vs. untreated: 20 (8-64) (mug/L) (P<0.0005)).

CONCLUSION

Short time discontinuation of HRT in young hypopituitary women increased liver enzymes, whereas measures of insulin sensitivity and lipid levels remained unchanged. We speculate that the estrogen component of HRT has beneficial effects on hepatic metabolism through various pathways. Further studies including liver imaging and with a time-dependent design are needed to clarify the role of HRT on liver enzyme levels, metabolic variables and liver fat content.

Severe XIST hypomethylation clearly distinguishes (SRY+) 46,XX-maleness from Klinefelter syndrome

OBJECTIVE

46,XX-maleness affects 1 in 20 000 live male newborns resulting in infertility and hypergonadotrophic hypogonadism. Although the phenotypes of XX-males have been well described, the molecular nature of the X chromosomes remains elusive. We assessed the X inactivation status by DNA methylation analysis of four informative loci and compared those to Klinefelter syndrome (KS) and Turner syndrome.

DESIGN AND METHODS

Patient cohort consisted of ten sex-determining region of the Y (SRY+) XX-males, two (SRY-) XX-males, ten 47,XXY Klinefelter men, six 45,X Turner females and ten male and female control individuals each. Methylation analysis was carried out by bisulphite sequencing of DNA from peripheral blood lymphocytes analysing X-inactive-specific transcript (XIST), phosphoglycerate kinase 1 (PGK1), ferritin, heavy peptide-like 17 (FTHL17) and short stature homeobox (SHOX).

RESULTS

XIST methylation was 18% in (SRY+) XX-males, and thus they were severely hypomethylated compared to (SRY-) XX-males (48%; P<0.01), Klinefelter men (44%; P<0.01) and female controls (47%; P<0.01). Turner females and male controls displayed a high degree of XIST methylation of 98 and 94% respectively. Methylation of PGK1, undergoing X inactivation, was not significantly reduced in (SRY+) XX-males compared to female controls in spite of severe XIST hypomethylation (51 vs 69%; P>0.05). FTHL17, escaping X inactivation, but undergoing cell-type-specific inactivation was similarly methylated in XX-males (89%), KS patients (87%) and female controls (90%). SHOX, an X inactivation escapee located in the pseudoautosomal region, displays similarly low degrees of methylation for XX-males (7%), KS patients (7%) and female controls (9%).

CONCLUSIONS

XIST hypomethylation clearly distinguishes (SRY+) XX-males from Klinefelter men. It does not, however, impair appropriate epigenetic regulation of representative X-linked loci.

Y chromosome in Turner syndrome: review of the literature

Turner syndrome (TS) is one of the most common types of aneuploidy among humans, and is present in 1:2000 newborns with female phenotype. Cytogenetically, the syndrome is characterized by sex chromosome monosomy (45,X), which is present in 50-60% of the cases. The other cases present mosaicism, with a 45,X cell line accompanied by one or more other cell lines with a complete or structurally abnormal X or Y chromosome. The presence of Y-chromosome material in patients with dysgenetic gonads increases the risk of gonadal tumors, especially gonadoblastoma. The greatest concern is the high risk of developing gonadoblastoma or other tumors and virilization during puberty if chromosome Y-specific sequences are present. The role of the Y chromosome in human oncogenesis is still controversial. Even though gonadoblastoma is a benign tumor, it can undergo transformation into invasive dysgerminoma in 60% of the cases, and also into other, malignant forms of germ cell tumors. Although some authors have questioned the high incidence of gonadoblastoma (around 30%), the risk of developing any kind of gonadal lesion, whether tumoral or not, justifies investigation of Y-chromosome sequences by means of the polymerase chain reaction (PCR), a highly sensitive, low-cost and easy-to-perform technique. In conclusion, mosaicism of both the X and the Y chromosome is a common finding in TS, and detection of Y-chromosome-specific sequences in patients, regardless of their karyotype, is necessary in order to prevent the development of gonadal lesions.

Increased prevalence of autoimmunity in Turner syndrome--influence of age

Individuals with Turner syndrome (TS) are prone to develop autoimmune conditions such as coeliac disease (CD), thyroiditis and type 1 diabetes (T1DM). The objective of the present study was to examine TS of various karyotypes for autoantibodies and corresponding diseases. This was investigated in a prospective cross-sectional study of Danish TS patients (n = 107, median age 36.7 years, range: 6-60 years). A medical history was recorded and a blood sample was analysed for autoantibodies against gliadin, transglutaminase, adrenal cortex, intrinsic factor, anti-thyroid peroxidase (anti-TPO) and glutamic-acid-decarboxylase 65 (GAD-65). Autoantibodies were present in 58% (n = 61) of all patients, whereof 18% (11) had autoantibodies targeting more than one organ. Patients with autoantibodies were significantly older than those without (P = 0.001). Anti-TPO was present in 45% (48) of patients, of whom 33% (16) were hypothyroid. Overall, 18% (19) presented with CD autoantibodies, of whom 26% (five) had CD. Anti-TPO and CD autoantibodies co-existed in 9% (10). Immunoglobulin A deficiency was found in 3% (three) of patients, who all had CD autoantibodies without disease. Among four patients with anti-GAD-65 none had T1DM, but two were classified as having T2DM. One patient had adrenocortical autoantibodies but not adrenal failure. Autoantibodies against intrinsic factor were absent. Anti-GAD-65 was increased in isochromosomal karyotypes (3/23 versus 1/84, P = 0.008) with no other association found between autoantibodies and karyotype. In conclusion, TS girls and women face a high prevalence of autoimmunity and associated disease with a preponderance towards hypothyroidism and CD. Thus, health care providers dealing with this patient group should be observant and test liberally for these conditions even before clinical symptoms emerge.

Fertility preservation in girls with turner syndrome: prognostic signs of the presence of ovarian follicles

CONTEXT

Many girls with Turner syndrome have follicles in their ovaries at adolescence.

OBJECTIVE

Our objective was to study which girls might benefit from ovarian tissue freezing for fertility preservation.

DESIGN

Clinical and laboratory parameters and ovarian follicle counts were analyzed among girls referred by 25 pediatric endocrinologists.

SUBJECTS AND SETTING

Fifty-seven girls with Turner syndrome, aged 8-19.8 yr, were studied at a university hospital.

INTERVENTIONS

Ovarian tissue was biopsied laparoscopically, studied for the presence of follicles, and cryopreserved. Blood samples were drawn for hormone measurements.

MAIN OUTCOME MEASURES

Presence of follicles in the biopsied tissue related to age, signs of spontaneous puberty, karyotype, and serum concentrations of gonadotropins and anti-Müllerian hormone were assessed.

RESULTS

Ovarian biopsy was feasible in 47 of the 57 girls. In 15 of the 57 girls (26%), there were follicles in the tissue piece analyzed histologically. Six of seven girls (86%) with mosaicism, six of 22 (27%) with structural chromosomal abnormalities, and three of 28 with karyotype 45X (10.7%) had follicles. Eight of the 13 girls (62%) with spontaneous menarche had follicles, and 11 of the 19 girls (58%) who had signs of spontaneous puberty had follicles. The age group 12-16 yr had the highest proportion of girls with follicles. Normal FSH and anti-Müllerian hormone concentrations for age and pubertal stage were more frequent in girls with follicles.

CONCLUSIONS

Signs of spontaneous puberty, mosaicism, and normal hormone concentrations were positive and statistically significant but not exclusive prognostic factors as regards finding follicles.

Acromegaly accompanied by Turner syndrome with 47,XXX/45,X/46,XX mosaicism

A 33-year-old woman was hospitalized for examination of edematous laryngopharynx. She was acromegalic. A pituitary adenoma with elevated serum levels of growth hormone (GH) and insulin-like growth factor-I (IGF-I) was detected, indicating acromegaly caused by GH-secreting pituitary adenoma. Multiple pigmented nevi were also noted without overt short stature and cubitus valgus. Chromosome analysis revealed that she had contracted Turner syndrome with 47,XXX/45,X/46,XX mosaicism. Transsphenoidal resection of the tumor decreased serum GH and IGF-I levels, but the edema was not improved. Both premature ovarian failure and hypertension appeared after surgery. This case may indicate the important relationships between GH/IGF-I and Turner syndrome.

Trends in age and anthropometric data at start of growth hormone treatment for girls with Turner syndrome in Japan

The purpose of this study is to evaluate the trends in age and anthropometric data for girls with Turner syndrome (TS) at start of growth hormone (GH) treatment in Japan. The data for analysis were obtained from a retrospective cohort, the Foundation for Growth Science, Japan. We analyzed trends in starting age of GH treatment for girls with TS in Japan after dividing subjects (n=1,478) into three registration periods: 1991-1994, 1995-1999 and 2000-2004. We also assessed the ratio of the subpopulation of subjects under five years of age. As results, the mean age (standard deviation (SD)) at start of GH treatment was significantly different among the three groups (10.95 (3.63), 10.15 (3.39) and 8.78 (3.61), p<0.0001). The proportion of the subjects under five years of age increased significantly over time (5.11%, 7.11% and 16.85%, p<0.0001). Mean (SD) height SD scores were also significantly different (-3.41 (0.87), -3.26 (0.81) and -3.17 (0.79), p<0.0001). However, the proportions of the karyotype of 45,X were not significantly different among the three groups (p=0.25). We concluded that age and shortness at initiation of GH treatment had been improving over time. However, these favorable trends have not fully met the conditions recommended by international clinical guidelines for TS.

Atherogenic lipid profile and systolic blood pressure are associated with carotid artery intima-media thickness in children with Turner syndrome

OBJECTIVE

Women with Turner syndrome (TS) have greater carotid artery intima-media thickness (cIMT) known to be a risk factor for atherosclerosis in adults. To determine whether there are risk factors for atherosclerosis in children with TS, we compared cIMT, anthropometric and metabolic parameters between children with TS and healthy controls.

METHODS

Data of children with TS with XO karyotype (n=24, mean age: 11.6±3.6) were compared with those of healthy children (n=24, mean age: 10.5±3.6) with respect to anthropometric parameters, lipid levels, insulin resistance and cIMT which was measured by high resolution B-mode ultrasonography.

RESULTS

Mean age and cIMT values were similar in the two groups of children. However in children with TS, fasting glucose (p=0.01), total cholesterol (p=0.006), triglyceride (p=0.04) levels and HDL-cholesterol (p=0.002) levels were higher than those of controls. In the TS group, cIMT correlated positively with LDL-cholesterol (r=0.435, p=0.034) and with systolic blood pressure (r=0.430, p=0.036) and negatively with HDL-cholesterol (r=-0.518, p=0.01). In stepwise regression analysis, HDL-cholesterol emerged as a significant predictor of cIMT (b= -0.518, p=0.01) contributing to 26.8 % of its variability.

CONCLUSION

The systolic blood pressure and dyslipidaemia were shown to be risk factors for atherosclerosis in children with TS.

Startling mosaicism of the Y-chromosome and tandem duplication of the SRY and DAZ genes in patients with Turner Syndrome

Presence of the human Y-chromosome in females with Turner Syndrome (TS) enhances the risk of development of gonadoblastoma besides causing several other phenotypic abnormalities. In the present study, we have analyzed the Y chromosome in 15 clinically diagnosed Turner Syndrome (TS) patients and detected high level of mosaicisms ranging from 45,XO:46,XY = 100:0% in 4; 45,XO:46,XY:46XX = 4:94:2 in 8; and 45,XO:46,XY:46XX = 50:30:20 cells in 3 TS patients, unlike previous reports showing 5-8% cells with Y- material. Also, no ring, marker or di-centric Y was observed in any of the cases. Of the two TS patients having intact Y chromosome in >85% cells, one was exceptionally tall. Both the patients were positive for SRY, DAZ, CDY1, DBY, UTY and AZFa, b and c specific STSs. Real Time PCR and FISH demonstrated tandem duplication/multiplication of the SRY and DAZ genes. At sequence level, the SRY was normal in 8 TS patients while the remaining 7 showed either absence of this gene or known and novel mutations within and outside of the HMG box. SNV/SFV analysis showed normal four copies of the DAZ genes in these 8 patients. All the TS patients showed aplastic uterus with no ovaries and no symptom of gonadoblastoma. Present study demonstrates new types of polymorphisms indicating that no two TS patients have identical genotype-phenotype. Thus, a comprehensive analysis of more number of samples is warranted to uncover consensus on the loci affected, to be able to use them as potential diagnostic markers.

Hearing loss in Turner syndrome: results of a multicentric study

The purpose of this article was to evaluate otological diseases in 173 patients (pts) with Turner syndrome (TS).

STUDY DESIGN

One hundred and seventy-three pts, mean chronological age (CA) 12+/-6.2 yr. Patients were submitted to different therapies: GH, estrogen therapy (EE), no therapy (no tx). Seventy-nine pts (CA 11 yr) had no otological diseases. Conductive hearing loss (CHL) occurred in 38.7% (CA 11 yr) and otoscopy was: persistent secretory otitis media in 55.2%, chronic otitis media in 10.4%, pars flaccida retraction pocket in 19.4%, mostly bilateral. Cholesteatoma was present in 15%. Sensorineurinal hearing loss (SNHL) occurred in 15.6% (CA 16 yr), 11 of whom were affected by high tone loss, and 15 by loss in midfrequencies (dip between 0.5-3 kHz), bilateral in 93%. Degree of hearing loss (HL) was mild [20-40 decibel hearing level (dBHL)] in 15%, moderate (45-60 dBHL) in 31%, severe (65-80 dBHL) in 8%, profound (dBHL>85) in 2%. We found a significant association between CHL and karyotype 45, X (p<0.025), congenital cranio-facial abnormalities, prevalently with low-set ears (p<0.04), narrow and/or high arched palate (p<0.018), and micrognathia (p<0.004). Our study confirms that the high prevalence of middle ear infections and CHL in TS are probably due to growth disturbances of the structures from the first and second branchial arches. We did not find any association between EE, GH, and HL. We recommend a regular audiological follow-up, especially during childhood, to prevent important middle ear anatomic sequele and to identify HL at an early stage, as the impact on social functioning may be significant.

O hormônio de crescimento na síndrome de Turner: dados e reflexões

A baixa estatura é a principal característica na síndrome de Turner (ST). O agravo estatural na ST é precoce e torna-se mais evidente na puberdade. A haploinsuficiência do gene SHOX tem sido implicada como principal fator na definição da estatura de mulheres, no entanto, ainda que a maioria das pacientes não tenha deficiência do hormônio de crescimento, a terapia com GHr melhora a altura final. Recentemente, tem-se chamado a atenção para a associação entre GH e câncer. O risco de câncer nessas pacientes está associado à presença de fragmentos do cromossomo Y que pode levar ao desenvolvimento de gonadoblastoma. Dessa forma, a administração de GHr na ST deve ser feita com cautela. A investigação de seqüências do cromossomo Y deve ser realizada, bem como a gonadectomia profilática nos casos positivos, conferindo maior segurança ao tratamento.

[Genetic analysis of Turner syndrome: 89 cases in Tunisia]

Turner's syndrome (TS) affects about 1/2500 female infants born alive. The syndrome results from total or partial absence of one of the two X chromosomes normally present in females. We report the results of a retrospective analysis of 89 cases of TS observed during a six-year period (2000-2005). The patients' age ranged from two days to 51 years at the time of this analysis. Most patients were adults (48%). The aim of this study is to ascertain the principal clinical features leading to a request for a karyotype, searching for a possible relationship between chromosomal anomalies and clinical expression of TS. Pediatric patients were referred for statural retardation or dysmorphic features, while reproduction anomalies were the main indication for karyotyping in patients aged over 20 years. Mosaicism was prevalent (47%), whereas the homogeneous karyotype 45,X was found in only 32% of the patients; structural anomalies were found in 21%. Regarding the advanced age of our patients, we established a relationship between chromosome anomalies and the clinical expression of TS, based on an analysis of stature and reproduction disorders. Short stature and primary amenorrhea were correlated with total deletion of one chromosome X or imbalanced gene dosage due to structural X anomalies. Whereas cases of infertility, recurrent miscarriages and secondary amenorrhea were associated with a mosaic karyotype pattern (45,X/46,XX or 45,X/46,XX/47,XXX ...), with a slight mosaicism in most cases. Thus, chromosome investigations should be performed in cases of reproduction failure even for women with normal stature.

Elevated liver enzymes in Turner syndrome during a 5-year follow-up study

OBJECTIVES

To study the prevalence and incidence of elevated liver enzymes and their relationship with body weight, metabolic factors and other diseases in Turner syndrome (TS).

DESIGN

Five-year follow-up.

PATIENTS

Women with TS (n = 218, mean age 33 +/- 13, range 16-71 years) from outpatient clinics at university hospitals in Sweden.

MEASUREMENTS

Fasting blood samples for aspartate (AST) and alanine aminotransferase (ALT), bilirubin, alkaline phosphatase (ALP), gamma-glutamyl transferase (GT), viral hepatitis serology and hepatic auto-antibodies, vitamin B12, blood glucose, lipids and hormones.

RESULTS

Seventy-nine subjects (36%) had one or more liver enzyme levels higher than the reference level, the most prevalent being GT. Karyotype 45,X was present in 51% of all TS women and in 48% of those with elevated liver enzymes. Body weight, body mass index (BMI), total cholesterol, triglycerides, and apolipoproteins A and B at start were higher in TS women with elevated liver enzymes than in TS women with normal levels. At 5 years, AST, ALT and GT were increased and another 23% of patients had developed elevated liver enzymes, that is, 59% in total (36% + 23%), while in 6%, the elevated liver enzymes had been normalized and all 6% also had lowered cholesterol levels. Multivariate analysis showed that GT was correlated with total cholesterol; P = 0.0032 at start and P = 0.0005 at 5 years, independently of other factors. Liver biopsy in six TS women showed one cholangitis, one hepatitis C, two steatosis and two normal biopsies. Withdrawal of oestrogen substitution did not influence the liver enzymes.

CONCLUSIONS

Pathological liver enzymes were common in TS women, with a prevalence of 36% at 33 years of age, an annual incidence over 5 years of 3.4%. There was no relation to karyotype, alcohol, viral hepatitis, E(2) or autoimmunity, but a connection with total serum cholesterol.

Hormonal therapy in a patient with a delayed diagnosis of Turner's syndrome

BACKGROUND

A 15-year-old girl presented to our clinic with short stature and delayed puberty. On examination her height was 139.3 cm, which is 13.2 cm below the 3(rd) percentile on a standard growth chart, and she had no clinical signs of puberty. A number of typical features of Turner's syndrome were found, including a short webbed neck, cubitus valgus, shield chest, multiple pigmented nevi, lymphedema, epicanthus and micrognathia.

INVESTIGATIONS

Plasma follicle-stimulating hormone and luteinizing hormone levels were increased. A pelvic ultrasound demonstrated a small uterus, but the ovaries could not be visualized. The patient's bone age was 12-13 years. A horseshoe kidney was seen on renal ultrasound and an echocardiography revealed aortic coarctation. The 45,X karyotype confirmed the diagnosis.

DIAGNOSIS

Turner's syndrome.

MANAGEMENT

Growth hormone therapy (1 IU/kg/week; approximately 0.05 mg/kg/day) was started together with oxandrolone (0.05 mg/kg/day) and transdermal estrogen. The dose of estrogen was gradually increased from 12.5 microg/day to 25.0 microg/day and then to 50.0 microg/day over a period of 12 months. Growth hormone and oxandrolone were withdrawn after 1 year, when the patient's epiphyses had fused. Hormonal replacement therapy with estrogens was continued and the patient has reached stage 3 of pubertal development and a final height of 148.5 cm.

Nailfold video capillaroscopy in Turner syndrome: a descriptive study

BACKGROUND: An increased prevalence of impaired glucose homeostasis is reported in Turner syndrome. Endothelial changes are described in patients with insulin resistance, which may be present in patients with Turner syndrome. Video capillaroscopy is a noninvasive examination that allows assessment of vascular patency. OBJECTIVE: To describe the nailfold morphology of capillaries in Turner syndrome using video capillaroscopy. METHODS: Subjects were studied in a temperature-controlled room, 20 days after no nailfold manipulations. The capillaries were visualized by microscope connected to a television and computer and were studied and classified according to these patterns: loop distribution, papilla, avascular fields, edema, form, capillary limbs, flow and hemorrhagic extravasation. RESULTS: Fifty patients aged between 6-37 years with Turner syndrome were studied. Eighteen (36%) patients had normal capillaroscopy with hairpin pattern in loop distribution and no avascular fields. The papilla was ratified in 13 (26%) and enlarged in four (8%). Edema occurred in 22 (44%) cases. There were three (6%) macrocapillaries and three (6%) were branched. Tortuosity was present in five (10%) patients. Hemorrhagic extravasation occurred in one (2%) case. Flow was fast in seven (14%), granulous in five (10%) and slow in six (12%). CONCLUSION: There was a high prevalence of nailfold capillaroscopy changes in Turner syndrome and the most prevalent alterations found were edema and ratified papilla.

Growth hormone (GH) treatment reduces peripheral thyroid hormone action in girls with Turner syndrome

OBJECTIVE

Turner syndrome (TS) is an indication for GH therapy in spite of the modest growth response. Somatic growth depends not only on GH insulin-like growth factor I (IGF-I) axis but also on thyroid hormone (TH) status. We have previously reported that supraphysiological IGF-I levels diminished TH actions in rat tissues by reducing the nuclear TH receptor (TR). GH treatment to TS patients induces high IGF-I levels and therefore a reduction of TH action in tissues may be expected. We aimed at evaluating the effect of GH therapy in TS girls on peripheral TH action.

DESIGN AND PATIENTS

We set up a reverse transcription-polymerase chain reaction (RT-PCR) for TR mRNA estimation in peripheral blood mononuclear cells (PBMC) and compared TR mRNA levels from 10 normal, 10 TS and 10 TS girls under GH therapy (0.33 mg/kg/week for 0.5-2 years).

MEASUREMENTS

After RNA extraction from PBMC, TR and beta-actin mRNAs were coamplified by RT-PCR. In addition serum biochemical markers of TH action were measured: thyrotropin (TSH), sex hormone binding globulin (SHBG), osteocalcin (OC), beta-crosslaps (beta-CL), iodothyronines by electrochemiluminescency and IGF-I by immunoradiometric assay (IRMA) with extraction.

RESULTS

TR mRNAs from PBMC were reduced in TS patients under GH treatment. In turn, serum TSH, OC, beta-CL and IGF-I were increased while SHBG was reduced by GH treatment in TS patients.

CONCLUSIONS

GH treatment reduced TR expression in PBMC and biochemical serum markers of TH action. These results suggest that GH treatment in TS patients impair peripheral TH action at tissue level and prompt a role in the reduced growth response to the therapy.

Growth hormone treatment of early growth failure in toddlers with Turner syndrome: a randomized, controlled, multicenter trial

CONTEXT

Typically, growth failure in Turner syndrome (TS) begins prenatally, and height sd score (SDS) declines progressively from birth.

OBJECTIVE

This study aimed to determine whether GH treatment initiated before 4 yr of age in girls with TS could prevent subsequent growth failure. Secondary objectives were to identify factors associated with treatment response, to determine whether outcome could be predicted by a regression model using these factors, and to assess the safety of GH treatment in this young cohort.

DESIGN

This study was a prospective, randomized, controlled, open-label, multicenter clinical trial (Toddler Turner Study, August 1999 to August 2003).

SETTING

The study was conducted at 11 U.S. pediatric endocrine centers.

SUBJECTS

Eighty-eight girls with TS, aged 9 months to 4 yr, were enrolled.

INTERVENTIONS

Interventions comprised recombinant GH (50 mug/kg.d; n = 45) or no treatment (n = 43) for 2 yr.

MAIN OUTCOME MEASURE

The main outcome measure was baseline-to-2-yr change in height SDS.

RESULTS

Short stature was evident at baseline (mean length/height SDS = -1.6 +/- 1.0 at mean age 24.0 +/- 12.1 months). Mean height SDS increased in the GH group from -1.4 +/- 1.0 to -0.3 +/- 1.1 (1.1 SDS gain), whereas it decreased in the control group from -1.8 +/- 1.1 to -2.2 +/- 1.2 (0.5 SDS decline), resulting in a 2-yr between-group difference of 1.6 +/- 0.6 SDS (P < 0.0001). The baseline variable that correlated most strongly with 2-yr height gain was the difference between mid-parental height SDS and subjects' height SDS (r = 0.32; P = 0.04). Although attained height SDS at 2 yr could be predicted with good accuracy using baseline variables alone (R(2) = 0.81; P < 0.0001), prediction of 2-yr change in height SDS required inclusion of initial treatment response data (4-month or 1-yr height velocity) in the model (R(2) = 0.54; P < 0.0001). No new or unexpected safety signals associated with GH treatment were detected.

CONCLUSION

Early GH treatment can correct growth failure and normalize height in infants and toddlers with TS.

IGF-I, IGFBP-3 and ALS generation test in Turner syndrome

OBJECTIVES

The pathophysiology of the short stature in girls with Turner syndrome (TS) is not well understood. The "IGF-I generation test" is used to assess the sensitivity to growth hormone. We compared the biochemical response to four days of growth hormone of TS and controls.

STUDY DESIGN

Pre-pubertal TS were recruited to participate in the study. Their siblings served as controls. IGF-I, IGFBP-3 and ALS were measured before and 5 days after using hGH (0.05mg/kg/day). Student-t test was used to compare the differences in their responses.

RESULTS

Eleven TS (mean age of 8.5+/-2.4) and 11 siblings (6 females and 5 males) (mean age of 7.0+/-2.0) participated in the study. The basal serum levels of IGF-I, IGFBP-3 and ALS were normal and not different between groups (p=0.62 for IGF-I, p=0.91 for IGFBP-3 and p=0.51 for ALS). The IGF-I generation test was positive in all controls and in 10/11 TS. The IGFBP-3 generation test was positive in 6/11 controls and 4/11 TS. After hGH the mean IGFBP-3 was lower in TS than in controls (p=0.08). The ALS response to hGH was not uniform between groups.

CONCLUSIONS

The IGF-I and ALS generation test results were not different between controls and TS. The IGFBP-3 results were higher in the control group but more than 50% of tested children did not pass. The IGF-I/IGFBP-3 generation tests, as presently done, did not help in the understanding of the short stature in TS. The use of different GH dosages and number of doses need to be investigated.

Chromosomal mosaicism mitigates stigmata and cardiovascular risk factors in Turner syndrome

OBJECTIVE

To study genotype-phenotype correlations in Turner syndrome (TS) regarding body composition, cardiovascular risk factors, stigmata and age at diagnosis vs. degree of mosaicism estimated as the percentage of 45,X and 46,XX cells.

METHODS

One hundred and twenty-six TS women, mean age 31 years, were examined by three specialists, who reported stigmata independent of each other. Dual energy X-ray absorptiometry (DXA) was used to measure bone mineral density (BMD). The karyotype was blinded. Fluorescence in situ hybridization (FISH) was performed on buccal cells. A random population sample served as controls.

RESULTS

Forty-four per cent exhibited a 45,X karyotype and 56% a second-cell line, while 27% of all had a 45,X/46,XX mosaicism. Five 45,X cases with a conventional karyotype were 45,X/46,XX mosaic according to FISH. At diagnosis, 45,X cases were younger (P < 0.05) and had more stigmata per person (P < 0.01) than the mosaics. TS with marker chromosome X or Y, iso or ring, did not differ from 45,X in this aspect. The mosaics had higher BMD and SHBG and lower total cholesterol and FSH than TS with 45,X and did not differ compared with controls in terms of body mass index (BMI), waist/hip ratio, BMD, blood pressure, cholesterol, triglycerides, SHBG, diabetes or osteoporosis. The number of stigmata correlated positively to BMI, waist/hip ratio, cholesterol and %45,X and inversely to height and %46,XX according to FISH.

CONCLUSIONS

Mosaicism seems to mitigate the TS phenotype and the cardiovascular risk factor profile. Mosaics were diagnosed 8 years later than 45,X cases. This emphasizes the necessity for a stricter genotype categorization not only in the clinic but also in research on TS than previously adopted.

Hearing loss in Turner syndrome

OBJECTIVE

To address the characteristics of hearing loss in patients with Turner syndrome (TS), we evaluated hearing levels of patients with TS and analyzed causative factors.

STUDY DESIGN

Thirty-three patients with TS (8 to 40 years of age) were studied through the use of audiological measurements, and causative factors were explored.

RESULTS

Twenty cases (35 of 66 ears tested) showed high-frequency (8 kHz) sensory neural hearing loss (HFQ-SNHL). Fifteen cases (26 ears) and 15 cases (24 ears) of the impaired 20 cases were unresponsive to distortion-product otoacoustic emissions and transient-evoked otoacoustic emissions, respectively. HFQ-SNHL showed little relation to the history of middle ear infection and puberty, although middle ear infections were seen in 11 of the 20 cases. The hearing thresholds at high frequencies were correlated with age and body height (P < .001). The age-dependent increase in hearing thresholds in the high frequencies was more apparent in patients with TS with monosomic 45, X than in those with the mosaic type (P < .05).

CONCLUSIONS

More than 60% of patients with TS had HFQ-SNHL. Because the increase in hearing threshold at high frequencies was shown to depend on karyotype and aging, regular otological examination is important for the determination of proper treatment.

Insulin resistance and body composition in Turner syndrome: Effect of sequential change in the route of estrogen administration

The aim of the present study was to examine the impact of sequential change in the route of estrogen administration on body composition and insulin resistance in patients with Turner syndrome (TS) using cyclical hormone replacement therapy (HRT) with conjugated equine estrogens (CEE) plus medroxyprogesterone acetate (MPA). We carried out a self-controlled study of nine non-obese patients with TS, with an average age of 23 +/- 4.9 years. Body mass index (BMI), waist-to-hip ratio (WHR), fasting glycemia, insulin tolerance (glucose disappearance constant during an insulin tolerance test, kITT) and body composition (dual-energy X-ray absorptiometry) were studied after 1 year's use of CEE plus MPA and repeated after 1 year's use of 17beta-estradiol gel with the same schedule of MPA administration. We did not observe any difference between the oral and percutaneous HRT with regard to BMI, WHR and insulin tolerance (kITT: 4.9 +/- 1.5 vs. 5.3 +/- 1.5%/min, p = 0.8). During administration of the 17beta-estradiol gel a tendency to increased total lean mass (p = 0.054) was observed. We conclude that sequential change in the route of estrogen administration in TS patients using cyclical HRT with CEE and MPA does not affect insulin resistance, although use of percutaneous 17beta-estradiol gel seems to exert favorable changes in body composition.

The correlation of the IGF-I, IGFBP-3, and ALS generation test to height velocity after 6 months of recombinant growth hormone therapy in girls with Turner syndrome

BACKGROUND/AIMS

Girls with Turner syndrome (TS) have short stature and benefit from growth hormone therapy (hGH). Some TS present a significant change in height velocity in response to hGH while others have only a mild increment. Our objective was to correlate the response to hGH (height velocity after 6 months of therapy) to biochemical data prior to and after the beginning of hGH to try to define a tool to predict the response to hGH.

METHODS

Thirteen TS participated in the study (ages 3.5-14 years). Levels of IGF-I and IGFBP-3 were measured before and 5, 30 and 90 days after starting hGH (0.05 mg/kg/day), ALS levels were measured only prior and after 5 days.

RESULTS

The mean height velocity (+/-SD) increased from 4.27 (+/-1.18) cm/year to 8.46 (+/-2.17) cm/year (p=0.0001). There was no correlation between the height velocity encountered and the expected height velocity using published mathematical models. Basal ALS values correlated to height velocity SDS and IGF-I and IGFBP-3, after 90 days, correlated to height velocity. Most of the data was too scattered to be used individually for each patient.

CONCLUSIONS

Even though we observed a relationship between biochemical markers and height velocity in TS treated with hGH, the response to hGH therapy in this condition is highly variable.