Turner Syndrome

Order chromosome analysis when a patient has otherwise unexplained short stature, delayed or absent puberty, primary ovarian insufficiency, infertility, or a compatible congenital cardiovascular or renal phenotype. The phenotype is heterogeneous, may evolve over time, and may be limited to growth impairment; Turner syndrome affects approximately 25 to 50 per 100,000 females. PubMed+2PubMedClinical practice guidelines for the care of girls and women with Turner syndrome: proceedings from the 2016 Cincinnati International Turner Syndrome Meeting - PubMedPubMedTurner Syndrome - StatPearls - NCBI BookshelfPubMedTurner Syndrome - StatPearls - NCBI Bookshelf - NIH

In girls with height below the third percentile, include Turner syndrome in the initial genetic differential even when routine blood counts, inflammatory markers, renal function, liver enzymes, and thyroid testing are normal. A normal screening laboratory profile does not exclude Turner syndrome, and diagnostic delay can defer growth treatment and recognition of comorbidities. JAMAJAMATesting the Tests

Prenatal findings that should prompt diagnostic counseling include increased nuchal translucency, cystic hygroma, hydrops, abnormal ductus venosus flow, or low pregnancy-associated plasma protein A. Cell-free DNA is a screening test rather than definitive confirmation; establish the fetal diagnosis with chorionic villus sampling or amniocentesis when clinically indicated. PubMedPubMedTurner Syndrome - StatPearls - NCBI Bookshelf - NIH

Peripheral-blood leukocyte karyotyping is the first diagnostic test for Turner syndrome. The laboratory standard historically includes analysis of at least 20 cells for mosaicism, while analysis of 30 metaphases provides approximately 95% confidence for detecting a 10% mosaic cell line. ScienceDirect+2ScienceDirectGenetic counseling for women with 45,X/46,XX mosaicism: Towards more personalized managementOxford AcademicDiagnosis of Turner Syndrome in the Eighth Decade of LifePubMedTurner Syndrome - StatPearls - NCBI Bookshelf - NIH

Do not infer absence of Turner-associated disease from a mild phenotype or a low proportion of 45,X cells in blood. Women with 45,X mosaicism can have average height and typical timing of menarche and menopause, but karyotype-phenotype correlations remain insufficiently consistent to individualize surveillance solely from the blood mosaic fraction. Nature+1NatureMosaic Turner syndrome shows reduced penetrance in an adult population study | Genetics in MedicineScienceDirectGenetic counseling for women with 45,X/46,XX mosaicism: Towards more personalized management

When 45,X/46,XY mosaicism or other Y-chromosome material is identified, assess gonadal anatomy and involve pediatric/adult endocrinology, gynecology, urology as appropriate, and genetics. Phenotypes range from mixed gonadal dysgenesis and ambiguous genitalia to a Turner phenotype with normal female secondary sexual characteristics; prophylactic gonadectomy is recommended at diagnosis because of gonadal tumor risk. WileyWileyMosaic Turner Syndrome Presenting with a 46,XY Karyotype

At diagnosis, organize care around congenital cardiovascular disease, aortic disease, renal anomalies, ovarian insufficiency, growth, thyroid and other autoimmune disease, hearing, vision, skeletal health, metabolic risk, and neurodevelopmental function. Turner syndrome is associated with congenital cardiovascular and renal anomalies, early sensorineural hearing loss, autoimmune thyroiditis and celiac disease, and a characteristic neurodevelopmental profile. PubMed+1PubMedClinical practice guidelines for the care of girls and women with Turner syndrome: proceedings from the 2016 Cincinnati International Turner Syndrome Meeting - PubMedPubMedTurner Syndrome - StatPearls - NCBI Bookshelf

Prioritize cardiovascular characterization because bicuspid aortic valve, coarctation of the aorta, aortic dilation, and hypertension materially alter pregnancy counseling and aortic risk. In a pregnancy cohort of thoracic aortic disease, most published Turner-associated dissections occurred in patients with congenital or acquired cardiovascular abnormalities, including bicuspid aortic valve, coarctation, or aortic dilation. BMJBMJPregnancy outcome in thoracic aortic disease data from the ...

Use a multidisciplinary longitudinal care model rather than an isolated genetics consultation. Guidelines frame Turner syndrome as a lifelong multisystem condition requiring coordinated pediatric-to-adult transition, with diagnostic/genetic, growth/developmental, cardiovascular, transition/adult-care, and comorbidity domains addressed explicitly. PubMed+1PubMedClinical practice guidelines for the care of girls and women with Turner syndrome: proceedings from the 2016 Cincinnati International Turner Syndrome Meeting - PubMedpublications aapClinical Practice Guidelines for the Care of Girls and Women With Turner Syndrome

Refer children promptly for growth-hormone evaluation after diagnosis or when Turner syndrome is strongly suspected. The 2016 international guideline recommended starting growth hormone at approximately 4 to 6 years of age and preferably before 12 to 13 years, supporting early rather than deferred referral when linear growth is impaired. ScienceDirectScienceDirectGrowth Hormone Treatment to Final Height in Turner ...

Assess spontaneous pubertal progression and ovarian function rather than assuming uniform gonadal failure. Premature ovarian insufficiency, delayed puberty, and infertility occur within the recognized Turner phenotype, while some women with 45,X mosaicism undergo menarche and menopause at average ages. Nature+1NatureMosaic Turner syndrome shows reduced penetrance in an adult population study | Genetics in MedicinePubMedTurner Syndrome - StatPearls - NCBI Bookshelf

Provide reproductive counseling before pregnancy attempts or assisted reproductive technology. International guidance supports comprehensive preconception assessment in women with Turner syndrome, and pregnancy—often requiring assisted reproductive technology—is associated with increased risk of aortic dissection. Wiley+1WileyReproductive health in Turner syndrome: A narrative reviewccjm2018 AHA/ACC Guideline for the Management of Adults ...

Transition planning should explicitly transfer responsibility for cardiovascular surveillance, reproductive and endocrine care, hearing and vision assessment, metabolic and autoimmune screening, bone health, and neurodevelopmental support. Turner syndrome guidelines identify transition and adult care as a dedicated domain because complications persist and may first become clinically consequential after pediatric follow-up ends. PubMed+1PubMedClinical practice guidelines for the care of girls and women with Turner syndrome: proceedings from the 2016 Cincinnati International Turner Syndrome Meeting - PubMedpublications aapClinical Practice Guidelines for the Care of Girls and Women With Turner Syndrome

Reassess cardiovascular status before any pregnancy-related decision, even in patients with prior uncomplicated health or a mosaic karyotype. In the reported thoracic aortic disease cohort, Turner participants included patients with preconception hypertension, bicuspid aortic valve, and documented aortic dilation despite no cardiovascular events during the observed pregnancies. BMJBMJPregnancy outcome in thoracic aortic disease data from the ...

Treat new clinical findings as phenotype changes requiring targeted reassessment rather than as evidence against the diagnosis. Development of hypertension, hearing loss, thyroid disease, celiac disease, metabolic complications, or reproductive problems should prompt condition-specific management within the broader Turner syndrome care plan. PubMed+1PubMedClinical practice guidelines for the care of girls and women with Turner syndrome: proceedings from the 2016 Cincinnati International Turner Syndrome Meeting - PubMedPubMedTurner Syndrome - StatPearls - NCBI Bookshelf