Development and validation of a computable phenotype for Turner syndrome utilizing electronic health records from a national pediatric network.

Turner syndrome (TS) is a genetic condition occurring in ~1 in 2000 females characterized by the complete or partial absence of the second sex chromosome. TS research faces similar challenges to many other pediatric rare disease conditions, with homogenous, single-center, underpowered studies. Secondary data analyses utilizing electronic health record (EHR) have the potential to address these limitations; however, an algorithm to accurately identify TS cases in EHR data is needed. We developed a computable phenotype to identify patients with TS using PEDSnet, a pediatric research network. This computable phenotype was validated through chart review; true positives and negatives and false positives and negatives were used to assess accuracy at both primary and external validation sites. The optimal algorithm consisted of the following criteria: female sex, ≥1 outpatient encounter, and ≥3 encounters with a diagnosis code that maps to TS, yielding an average sensitivity of 0.97, specificity of 0.88, and C-statistic of 0.93 across all sites. The accuracy of any estradiol prescriptions yielded an average C-statistic of 0.91 across sites and 0.80 for transdermal and oral formulations separately. PEDSnet and computable phenotyping are powerful tools in providing large, diverse samples to pragmatically study rare pediatric conditions like TS.

Inspiring New Science to Guide Healthcare in Turner Syndrome: Rationale, design, and methods for the InsighTS Registry.

Inspiring New Science to Guide Healthcare in Turner Syndrome (InsighTS) Registry is a national, multicenter registry for individuals with Turner syndrome (TS) designed to collect and store validated longitudinal clinical data from a diverse cohort of patients with TS. Herein, we describe the rationale, design, and approach used to develop the InsighTS registry, as well as the demographics of the initial participants to illustrate the registry's diversity and future utility. Multiple stakeholder groups have been involved from project conceptualization through dissemination, ensuring the registry serves the priorities of the TS community. Key features of InsighTS include recruitment strategies to facilitate enrollment of participants that appropriately reflect the population of individuals with TS receiving care in the US, clarity of data ownership and sharing, and sustainability of this resource. The registry gathers clinical data on diagnosis, treatment, comorbidities, health care utilization, clinical practices, and quality of life with the goal of improving health outcomes for this population. Future directions include multiple patient-centered clinical-translational research projects that will use the InsighTS platform. This thorough and thoughtful planning will ensure InsighTS is a valuable and sustainable resource for the TS community for decades to come.

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.

Hepatic abnormalities in youth with Turner syndrome.

BACKGROUND & AIMS: Liver disease in children with Turner Syndrome (TS) is poorly understood relative to associated growth, cardiac and reproductive complications. This study sought to better characterize hepatic abnormalities in a large national cohort of youth with TS. METHODS: Using electronic health record data from PEDSnet institutions, 2145 females with TS were matched to 8580 females without TS on eight demographic variables. Outcomes included liver enzymes (AST and ALT) stratified as normal, 1-2 times above the upper limit of normal (ULN), 2-3 times ULN and >3 times ULN, as well as specific liver disease diagnoses. RESULTS: Fifty-eight percent of youth with TS had elevated liver enzymes. Patients with TS had higher odds of enzymes 1-2 times ULN (OR: 1.7, 95% CI: 1.4-1.9), 2-3 times ULN (OR: 2.7, 95% CI: 1.7-3.3) and >3 times ULN (OR: 1.7, 95% CI: 1.3-2.2). They also had higher odds of any liver diagnosis (OR: 2.4, 95% CI: 1.7-3.3), fatty liver disease (OR: 1.9, 95% CI: 1.1-3.2), hepatitis (OR: 3.7, 95% CI: 1.9-7.1), cirrhosis/fibrosis (OR: 5.8, 95% CI: 1.3-25.0) and liver tumour/malignancy (OR: 4.8, 95% CI: 1.4-17.0). In a multinomial model, age, BMI and presence of cardiovascular disease or diabetes significantly increased the odds of elevated liver enzymes in girls with TS. CONCLUSIONS: Youth with TS have higher odds for elevated liver enzymes and clinically significant liver disease compared with matched controls. These results emphasize the need for clinical screening and additional research into the aetiology and treatment of liver disease in TS. LAY SUMMARY: Turner Syndrome, a chromosomal condition in which females are missing the second sex chromosome, is often associated with short stature, infertility and cardiac complications. Liver abnormalities are less well described in the literature. In this study, nearly 60% of youth with TS have elevated liver enzymes. Furthermore, patients with TS had a diagnosis of liver disease more often than patients without TS. Our results support the importance of early and consistent liver function screening and of additional research to define mechanisms that disrupt liver function in paediatric TS females.

Cell-free DNA screening positive for monosomy X: clinical evaluation and management of suspected maternal or fetal Turner syndrome.

Initially provided as an alternative to evaluation of serum analytes and nuchal translucency for the assessment of pregnancies at high risk of trisomy 21, cell-free DNA screening for fetal aneuploidy, also referred to as noninvasive prenatal screening, can now also screen for fetal sex chromosome anomalies such as monosomy X as early as 9 to 10 weeks of gestation. Early identification of Turner syndrome, a sex chromosome anomaly resulting from the complete or partial absence of the second X chromosome, allows medical interventions such as optimizing obstetrical outcomes, hormone replacement therapy, fertility preservation and support, and improved neurocognitive outcomes. However, cell-free DNA screening for sex chromosome anomalies and monosomy X in particular is associated with high false-positive rates and low positive predictive value. A cell-free DNA result positive for monosomy X may represent fetal Turner syndrome, maternal Turner syndrome, or confined placental mosaicism. A positive screen for monosomy X with discordant results of diagnostic fetal karyotype presents unique interpretation and management challenges because of potential implications for previously unrecognized maternal Turner syndrome. The current international consensus clinical practice guidelines for the care of individuals with Turner syndrome throughout the lifespan do not specifically address management of individuals with a cell-free DNA screen positive for monosomy X. This study aimed to provide context and expert-driven recommendations for maternal and/or fetal evaluation and management when cell-free DNA screening is positive for monosomy X. We highlight unique challenges of cell-free DNA screening that is incidentally positive for monosomy X, present recommendations for determining if the result is a true-positive, and discuss when diagnosis of Turner syndrome is applicable to the fetus vs the mother. Whereas we defer the subsequent management of confirmed Turner syndrome to the clinical practice guidelines, we highlight unique considerations for individuals initially identified through cell-free DNA screening.

The Turner syndrome research registry: Creating equipoise between investigators and participants.

To address knowledge gaps about Turner syndrome (TS) associated disease mechanisms, the Turner Syndrome Society of the United States created the Turner Syndrome Research Registry (TSRR), a patient-powered registry for girls and women with TS. More than 600 participants, parents or guardians completed a 33-item foundational survey that included questions about demographics, medical conditions, psychological conditions, sexuality, hormonal therapy, patient and provider knowledge about TS, and patient satisfaction. The TSRR platform is engineered to allow individuals living with rare conditions and investigators to work side-by-side. The purpose of this article is to introduce the concept, architecture, and currently available content of the TSRR, in anticipation of inviting proposals to utilize registry resources.

The impact of hypocalcemia on full scale IQ in patients with 22q11.2 deletion syndrome.

Hypocalcemia has been reported in ~50% of patients 22q11.2DS and calcium regulation is known to play a role in neuronal development and synaptic plasticity. Because calcium ions play a role in neuronal function and development, we hypothesized that hypocalcemia would be associated with adverse effects on full scale IQ index (FSIQ) in patients with 22q11.2DS. A retrospective chart review cataloguing the presence or absence of hypocalcemia in 1073 subjects with a laboratory confirmed chromosome 22q11.2 deletion evaluated at the Children's Hospital of Philadelphia was conducted. 852/1073 patients had an endocrinology evaluation with laboratory confirmed calcium levels. 466/852 (54.7%) had a diagnosis of hypocalcemia. 265/1073 subjects ranging from 0 to 51 years of age had both calcium levels measured and a neuropsychological evaluation yielding a FSIQ. The mean FSIQ for 146/265 patients with hypocalcemia was 77.09 (SD = 13.56) and the mean FSIQ for 119/265 patients with normocalcemia was 77.27 (SD = 14.25). The distribution of patients with intellectual disability (ID) (FSIQ<69), borderline IQ (FSIQ 70-79), and average IQ (FSIQ>80) between the hypocalcemic and normocalcemic groups was not statistically significant (χ2 = 0.2676, p = 0.8748). Neonatal hypocalcemic seizures were not found to be associated with ID. We found no difference in FSIQ between the hypocalcemic and non-hypocalcemic patients with 22q11.2DS. As our findings differ from a previous report in adult subjects, we speculate that this may reflect a potential benefit from early treatment of hypocalcemia and may support early 22q11.2 deletion detection in order to offer prompt diagnosis and subsequent treatment of hypocalcemia.

Turner Syndrome: Care of the Patient: Birth to Late Adolescence.

Turner syndrome (TS) is a genetic condition occurring in females resulting from the loss of part or all of one of the X chromosomes. The two hallmark features of Turner syndrome include short stature and primary ovarian insufficiency. In addition, Turner syndrome can involve multiple healthcare issues including cardiac and renal anomalies, autoimmune disorders, hearing loss, ophthalmologic issues, bone anomalies, dermatologic issues and psychosocial and educational concerns. The presenting signs of Turner syndrome can vary markedly, leading to delayed or even missed diagnosis. Early identification of TS allows for appropriate screening and surveillance evaluations and more timely treatment intervention. This article will provide an overview of the healthcare issues common to patients with TS, treatments available and the screening and surveillance testing that is recommended.

Turner syndrome: fertility counselling in childhood and through the reproductive lifespan.

PURPOSE OF REVIEW: The potential for fertility in Turner syndrome has improved in recent years. Understanding of associated risks and approaches is important for the care of girls and women with this condition. This review focuses on reproductive health, fertility options and appropriate counselling for women with Turner syndrome and their families. RECENT FINDINGS: Women with Turner syndrome have rapidly declining ovarian function beginning in utero . Therefore, counselling regarding fertility concerns should begin at a young age and involve discussion of options, including ovarian tissue cryopreservation, oocyte preservation and use of nonautologous oocytes. Clinical guidance on fertility management and pregnancy risk assessment based on karyotype, associated comorbidities and fertility is still not fully data driven. Realistic expectations regarding reproductive options and associated outcomes as well as the need for multidisciplinary follow-up during pregnancy are crucial to the ethical and safe care of these patients. SUMMARY: Fertility care in women with Turner syndrome is evolving as current management techniques improve and new approaches are validated. Early counselling and active management of fertility preservation is critical to ensure positive and well tolerated reproductive outcomes.