Phenotype, ovarian function, and growth in patients with 45,X/47,XXX Turner mosaicism: implications for prenatal counseling and estrogen therapy at puberty

Prevalence, diagnostic features, and medical outcomes of females with Turner syndrome with a trisomy X cell line (45,X/47,XXX): Results from the InsighTS Registry

Turner syndrome (TS) is defined by partial or complete absence of a sex chromosome. Little is known about the phenotype of individuals with TS mosaic with trisomy X (45,X/47,XXX or 45,X/46,XX/47,XXX) (~3% of TS). We compared the diagnostic, perinatal, medical, and neurodevelopmental comorbidities of mosaic 45,X/47,XXX (n = 35, 9.4%) with nonmosaic 45,X (n = 142) and mosaic 45,X/46,XX (n = 66). Females with 45,X/47,XXX had fewer neonatal concerns and lower prevalence of several TS-related diagnoses compared with 45,X; however the prevalence of neurodevelopmental and psychiatric diagnoses were not different. Compared to females with 45,X/46,XX, the 45,X/47,XXX group was significantly more likely to have structural renal anomalies (18% vs. 3%; p = 0.03). They were twice as likely to have congenital heart disease (32% vs. 15%, p = 0.08) and less likely to experience spontaneous menarche (46% vs. 75% of those over age 10, p = 0.06), although not statistically significant. Congenital anomalies, hypertension, and hearing loss were primarily attributable to a higher proportion of 45,X cells, while preserved ovarian function was most associated with a higher proportion of 46,XX cells. In this large TS cohort, 45,X/47,XXX was more common than previously reported, individuals were phenotypically less affected than those with 45,X, but did have trends for several more TS-related diagnoses than individuals with 45,X/46,XX.

Chromosomal Abnormalities of Interest in Turner Syndrome: An Update

Turner syndrome (TS) is caused by the total or partial loss of the second sex chromosome; it occurs in 1 every 2,500-3,000 live births. The clinical phenotype is highly variable and includes short stature and gonadal dysgenesis. In 1959, the chromosomal origin of the syndrome was recognized; patients had 45 chromosomes with a single X chromosome. TS presents numerical and structural abnormalities in the sex chromosomes, interestingly only 40% have a 45, X karyotype. The rest of the chromosomal abnormalities include mosaics, deletions of the short and long arms of the X chromosome, rings, and isochromosomes. Despite multiple studies to establish a relationship between the clinical characteristics and the different chromosomal variants in TS, a clear association cannot yet be established. Currently, different mechanisms involved in the phenotype have been explored. This review focuses to analyze the different chromosomal abnormalities and phenotypes in TS and discusses the possible mechanisms that lead to these abnormalities.

Ovarian dysfunction in women with Turner syndrome

Ovarian dysfunction is one of the most common features of women with Turner syndrome. In these women, oocyte apoptosis is markedly accelerated from the early stage of fetal life. Reduction in the number of germ cells disturbs primordial follicle development and thereby leads to the formation of streak gonads. There are three possible causes of accelerated germ cell loss in 45,X ovaries. First, chromosomal pairing failure due to X chromosomal aneuploidy is believed to induce meiotic arrest. Indeed, it has been suggested that the dosage of the X chromosome is more critical for the survival of the oocytes than for other cells in the ovary. Second, impaired coupling between oocytes and granulosa cells may also contribute to germ cell apoptosis. Previous studies have shown that 45,X ovaries may tend to lose tight junctions which are essential for intercellular interactions. Lastly, ovarian dysfunction in women with Turner syndrome is partly attributable to the reduced dosage of several genes on the X chromosome. Specifically, BMP15, PGRMC1, and some other genes on the X chromosome have been implicated in ovarian function. Further studies on the mechanisms of ovarian dysfunction are necessary to improve the reproductive outcomes of women with Turner syndrome.

Human sex chromosome aneuploidies: The hypothalamic-pituitary-gonadal axis

Sex chromosome aneuploidies (SCA) are relatively common as a group, perhaps 1 per 500 births, but much more common at conception. Many syndromes have been noted in those with these conditions, but not so many data are available concerning the hypothalamic-pituitary-gonadal (HPG) axis. The physiology of the HPG axis is first reviewed at four epochs in time: fetal, birth and mini-puberty, childhood, and adolescence (puberty). Those sections are followed by detailed analysis of the functioning of the HPG axis in individuals with specific SCA with chromosomal numbers ranging from 45 to 49. Robust data are available for the chromosomal complements 47,XXY and 47,XXX with fewer data available for many of the others.

Primary gonadal failure

The term primary gonadal failure encompasses not only testicular insufficiency in 46,XY males and ovarian insufficiency in 46,XX females, but also those disorders of sex development (DSD) which result in gender assignment that is at variance with the genotype and gonadal type. In boys, causes of gonadal failure include Klinefelter and other aneuploidy syndromes, bilateral cryptorchidism, testicular torsion, and forms of 46,XY DSD such as partial androgen insensitivity. Causes in girls include Turner syndrome and other aneuploidies, galactosemia, and autoimmune ovarian failure. Iatrogenic causes in both boys and girls include the late effects of childhood cancer treatment, total body irradiation prior to bone marrow transplantation, and iron overload in transfusion-dependent thalassaemia. In this paper, a brief description of the physiology of testicular and ovarian development is followed by a section on the causes and practical management of gonadal impairment in boys and girls. Protocols for pubertal induction and post-pubertal hormone replacement - intramuscular, oral and transdermal testosterone in boys; oral and transdermal oestrogen in girls - are then given. Finally, current and future strategies for assisted conception and fertility preservation are discussed.

Ovarian reserve evaluation in a woman with 45,X/47,XXX mosaicism: A case report and a review of literature

Background

Turner syndrome (TS) is a common chromosomal disorder affecting approximately 1:2,500 live female births. Mosaic 47,XXX karyotype is found in 3%–4% of TS patients. TS phenotype in rare 45,X/47,XXX mosaicism patients is milder than in classic TS, however their ovarian function, especially in the mature age, has not been described in detail.

Methods

A case report and literature review.

Results

A 30‐year‐old woman with menstrual irregularity and primary infertility presented with short stature and multiple nevi on the face without other common TS clinical features. She had spontaneous puberty and menarche but diminished ovarian reserve at the age of 30. Fluorescence in situ hybridization (FISH) indicated 45,X/47,XXX mosaicism, which was once misdiagnosed as 45,X monosomy. Literature review revealed the prevalence of short stature in only 64.3% of 45,X/47,XXX mosaicism cases, that is, much less frequently than in pure 45,X monosomy. The risk of premature ovarian insufficiency in 45,X/47,XXX mosaicism patients is higher, and ovarian failure is usually observed at around 30 years of age.

Conclusion

FISH should be recommended to evaluate low proportion mosaicism in similar cases. Due to the risk of ovarian failure, fertility preservation for patients with 45,X/47,XXX mosaicism at a younger age must be considered.

A Spontaneous Pregnancy in a Patient with Turner Syndrome with 45,X/47,XXX Mosaicism: A Case Report and Review of the Literature

BACKGROUND

Turner syndrome is a chromosomal abnormality, due to a total or partial loss of 1 of the X chromosomes and is mostly characterized clinically by short stature and primary ovarian insufficiency. Spontaneous pregnancies are rare (5%) and of relatively high risk. This is 1 of few reported cases of spontaneous conception and favorable prognosis in a patient with Turner syndrome and a 45,X/47,XXX karyotype.

CASE

A 21-year-old woman with Turner mosaicism (45,X/47,XXX) who had a full-term, uncomplicated pregnancy after spontaneous conception, gave birth to a healthy female (46,XX) infant.

SUMMARY AND CONCLUSION

Spontaneous pregnancies in women with Turner syndrome are a rarity. Fertility preservation methods are being discussed. Due to the high reported incidence of neonatal, obstetric, maternal, and especially cardiovascular complications in those pregnancies, close monitoring is essential.

Measured parental height in Turner syndrome-a valuable but underused diagnostic tool

Early diagnosis of Turner syndrome (TS) is necessary to facilitate appropriate management, including growth promotion. Not all girls with TS have overt short stature, and comparison with parental height (Ht) is needed for appropriate evaluation. We examined both the prevalence and diagnostic sensitivity of measured parental Ht in a dedicated TS clinic between 1989 and 2013. Lower end of parental target range (LTR) was calculated as mid-parental Ht (correction factor 12.5 cm minus 8.5 cm) and converted to standard deviation scores (SDS) using UK 1990 data, then compared with patient Ht SDS at first accurate measurement aged > 1 year. Information was available in 172 girls of whom 142 (82.6%) were short at first measurement. However, both parents had been measured in only 94 girls (54.6%). In 92 of these girls age at measurement was 6.93 ± 3.9 years, Ht SDS vs LTR SDS - 2.63 ± 0.94 vs - 1.77 ± 0.81 (p < 0.001), Ht SDS < LTR in 78/92 (85%). Eleven of the remaining 14 girls were < 5 years, while karyotype was 45,X/46,XX in 2 and 45,X/47,XXX in 3.

CONCLUSION

This study confirms the sensitivity of evaluating height status against parental height but shows that the latter is not being consistently measured. What is Known: • Girls with Turner syndrome are short in relation to parental heights, with untreated final height approximately 20 cm below female population mean. • Measured parental height is more accurate than reported height. What is New: • In a dedicated Turner clinic, there was 85% sensitivity when comparing patient height standard deviation score at first accurate measurement beyond 1 year of age with the lower end of the parental target range standard deviation. • However, measured height in both parents had been recorded in only 54.6% of the Turner girls attending the clinic. This indicates the need to improve the quality of growth assessment in tertiary care.

Incidence, puberty, and fertility in 45,X/47,XXX mosaicism: Report of a patient and a literature review

Turner syndrome (TS), characterized by short stature and premature ovarian failure, is caused by chromosomal aberrations with total or partial loss of one of the two X chromosomes. Spontaneous puberty, menarche, and pregnancy occur in some patients depending on the abnormality of the X. Moreover, spontaneous pregnancy is uncommon (<0.5%) for TS with 45,X monosomy. Among TS patients, 45,X/47,XXX karyotype is extremely rare. Previous reports have demonstrated that TS with 45,X/47,XXX is less severe than common TS due to higher occurrence of puberty (83%), menarche (57-67%), and fertility (14%) and lower occurrence of congenital anomalies (<5%). However, TS mosaicism may not reduce the frequency of short stature. We diagnosed a 10-year-girl with TS with 45,X/47,XXX mosaicism who presented with short stature. She showed mild TS phenotype including short stature but had spontaneous puberty. Based on our case and previous reports, we expect that girls with 45,X/47,XXX mosaicism may progress through puberty normally, without estrogen therapy. Therefore, it is necessary to consider specific guidelines for clinical decisions surrounding pubertal development and fertility in TS with 45,X/47,XXX karyotype.

The Turner syndrome in patient with 45X/47XXX mosaic karyotype--case report

BACKGROUND

Turner syndrome (TS) is a gonadal dysgenesis related to partial or total lack of one of the X chromosomes. It this report we describe a young patient presenting some somatic features of TS, who underwent spontaneous puberty and was eumenoorheic up to the age of 23.

METHODS

Using fluorescent in situ hybridization (FISH) mosaic karyotype (45X[131]/47XXX[9]) of TS and triple X syndrome was found.

RESULTS

She presented uncommon for TS somatic hemihypotrophy and underwent growth hormone and surgical therapy. The patient was diagnosed with premature ovarian failure when she was 23, with absent follicular reserve. Clinical features of this case and a few published cases will be reviewed briefly.

45,X/47,XXX Mosaicism and Short Stature

We describe the case of a ten-year-old girl with short stature and 45,X/47,XXX genotype. She also suffered from vesicoureteric reflux and kidney dysfunction prior to having surgery on her ureters. Otherwise, she does not have any of the characteristics of Turner nor Triple X syndrome. It has been shown that this mosaic condition as well as other varieties creates a milder phenotype than typical Turner syndrome, which is what we mostly see in our patient. However, this patient is a special case, because she is exceptionally short. Overall, one cannot predict the resultant phenotype in these mosaic conditions. This creates difficulty in counseling parents whose children or fetuses have these karyotypes.

Cholesteatoma has a high prevalence in Turner syndrome, highlighting the need for earlier diagnosis and the potential benefits of otoscopy training for paediatricians

AIM

Girls with Turner syndrome are prone to cholesteatoma, a serious suppurative middle ear disease. We aimed to confirm its high prevalence in Turner syndrome, identify risk factors and suggest possible strategies for earlier detection.

METHODS

We reviewed 179 girls with Turner syndrome between 1989 and 2012 to identify cases of cholesteatoma.

RESULTS

Seven girls (3.9%) had cholesteatoma (index girls) and each was compared with three age-matched girls without cholesteatoma (comparison girls). All the index girls had either the 45,X or 45,X/46X,i(Xq) karyotypes. Nine ears were initially affected, with three recurrences in two girls. Median age at first cholesteatoma presentation was 11.9 years (range: 7.5-15.2), with otorrhoea for three (range: one to seven) months in all 12 affected ears. Index girls had a significantly higher proportion of previous recurrent acute (p = 0.007) and chronic otitis media (p = 0.008), chronic perforation (p = 0.038) aural polyps (p < 0.0001) and tympanic membrane retraction (p = 0.0001) than comparison girls.

CONCLUSION

Cholesteatoma has a high prevalence in Turner syndrome. Risk factors include 45,X and 46,XiXq karyotypes; a history of chronic otitis media, tympanic membrane retraction and persistent otorrhoea; and older age. Earlier recognition of ear disease is needed and otoscopy training for paediatricians caring for Turner syndrome patients may be beneficial.

Fertility in Turner syndrome

There is increasing interest in fertility and use of assisted reproductive technologies for women with Turner syndrome (TS). Current parenting options include adoption, surrogacy, and spontaneous and assisted reproduction. For women with TS, specific risks of pregnancy include higher than usual rates of spontaneous abortion, foetal anomaly, maternal morbidity and mortality. Heterologous fertility assistance using oocytes from related or unrelated donors is an established technique for women with TS. Homologous fertility preservation includes cryopreservation of the patient's own gametes prior to the progressive ovarian atresia known to occur: preserving either mature oocytes or ovarian tissue containing primordial follicles. Mature oocyte cryopreservation requires ovarian stimulation and can be performed only in postpubertal individuals, when few women with TS have viable oocytes. Ovarian tissue cryopreservation, however, can be performed in younger girls prior to ovarian atresia - over 30 pregnancies have resulted using this technique, however, none in women with TS. We recommend consideration of homologous fertility preservation techniques in children only within specialized centres, with informed consent using protocols approved by a research or clinical ethics board. It is essential that further research is performed to improve maternal and foetal outcomes for women with TS.

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.

Effect of oxandrolone and timing of pubertal induction on final height in Turner's syndrome: randomised, double blind, placebo controlled trial

OBJECTIVE

To examine the effect of oxandrolone and the timing of pubertal induction on final height in girls with Turner's syndrome receiving a standard dose of growth hormone.

DESIGN

Randomised, double blind, placebo controlled trial. Setting 36 paediatric endocrinology departments in UK hospitals.

PARTICIPANTS

Girls with Turner's syndrome aged 7-13 years at recruitment, receiving recombinant growth hormone therapy (10 mg/m(2)/week).

INTERVENTIONS

Participants were randomised to oxandrolone (0.05 mg/kg/day, maximum 2.5 mg/day) or placebo from 9 years of age. Those with evidence of ovarian failure at 12 years were further randomised to oral ethinylestradiol (year 1, 2 µg daily; year 2, 4 μg daily; year 3, 4 months each of 6, 8, and 10 μg daily) or placebo; participants who received placebo and those recruited after the age of 12.25 years started ethinylestradiol at age 14.

MAIN OUTCOME MEASURE

Final height. Results 106 participants were recruited, of whom 14 withdrew and 82/92 reached final height. Both oxandrolone and late pubertal induction increased final height: by 4.6 (95% confidence interval 1.9 to 7.2) cm (P = 0.001, n = 82) for oxandrolone and 3.8 (0.0 to 7.5) cm (P = 0.05, n = 48) for late pubertal induction with ethinylestradiol. In the 48 children who were randomised twice, the effects on final height (compared with placebo and early induction of puberty) of oxandrolone alone, late induction alone, and oxandrolone plus late induction were similar, averaging 7.1 (3.4 to 10.8) cm (P < 0.001). No cases of virilisation were reported.

CONCLUSION

Oxandrolone had a positive effect on final height in girls with Turner's syndrome treated with growth hormone, as did late pubertal induction with ethinylestradiol at age 14 years. However, these effects were not additive, so using both had no advantage. Oxandrolone could, therefore, be offered as an alternative to late pubertal induction for increasing final height in Turner's syndrome. Trial registration Current Controlled Trials ISRCTN50343149.

Turner's syndrome and pregnancy: has the 45,X/47,XXX mosaicism a different prognosis? Own clinical experience and literature review

Turner's syndrome is characterized by an ovarian failure which occurs in most cases before puberty and leads to infertility. In less than 10% of women with Turner syndrome, puberty may occur and spontaneous pregnancies is possible but with a high risk of fetal loss, chromosomal and congenital abnormalities. We present the case of a 33-year-old woman with a mosaic Turner's syndrome karyotype 45,X/47,XXX who conceived spontaneously and had two successful pregnancies. Short stature was the only manifestation of Turner's syndrome. In the present report, we reviewed the available literature on the fertility of women with Turner's syndrome and the phenotypic effects of mosaicism for a 47,XXX cell line in Turner's syndrome.

Optimising management in Turner syndrome: from infancy to adult transfer

Turner syndrome can be defined as loss or abnormality of the second X chromosome in at least one cell line in a phenotypic female. The condition occurs in approximately 1 in every 2000 live female births,(1) so that in the UK the prevalence for any year of life is in the region of 200 girls. The condition is much more common in utero, it being estimated that 1-2% of all conceptuses are affected, of whom only 1% will survive to term.

Prader-Willi syndrome and mosaic Turner's syndrome

We present a female with both Prader-Willi syndrome and Turner's syndrome, a combination not previously reported. We review her clinical presentation and discuss her growth pattern, mental development, and puberty, in relation to her mosaic Turner and Prader-Willi syndromes.

Poor uterine development in Turner syndrome with oral oestrogen therapy

OBJECTIVE

To evaluate uterine development in Turner syndrome (TS) patients in relation to treatment with oral ethinyl oestradiol (E2 ) for pubertal induction.

DESIGN AND PATIENTS

Pelvic ultrasound data for 96 TS patients scanned since 1989 were analysed. Patients were classified into three groups: (1) untreated (n = 48); (2) complete spontaneous puberty (n = 10); and (3) treated with ethinyl oestradiol (n = 38). Uterine development was described in the three groups and compared with the normal data.

MEASUREMENTS

Uterine length, fundal-cervical ratio (FCR) and shape were recorded, and presence or absence of ovaries noted. In the treated group, cross-sectional and longitudinal data were combined to compare uterine development with Tanner breast stage.

RESULTS

In untreated girls up to age 10 years there was a variable distribution of uterine length and FCR about the mean. Thereafter, the uterus failed to grow and mature normally. Girls with complete spontaneous puberty had morphologically normal ovaries and uteri, but of 7 girls who attained menarche, 3 subsequently developed secondary oligomenorrhoea or amenorrhoea. In the treated group, in general, breast development and uterine length progressed with increasing E2 dose. However, only 50% of girls with complete secondary sexual development had a mature heart-shaped uterine configuration.

CONCLUSIONS

Our current E2 treatment regimen for TS girls gives rise to satisfactory pubertal induction and maintenance, but failed to induce a fully mature uterus in half the cohort. In view of the high risk of miscarriage in TS in both spontaneous and assisted pregnancies, the effect of more physiological methods of E2 replacement on uterine development should be investigated.