Presentation: Clinical suspicion of Turner syndrome
Girls with Turner syndrome have one normal X chromosome, rather than the usual two. They can present pre- or postnatally with a range of clinical features.
Example clinical scenario
A 14-year-old girl is referred to the paediatric clinic by her GP because she hasn’t yet started her period.
When to consider genomic testing
Turner syndrome may be suspected at different ages following different presentations.
- Prenatally:
- a raised nuchal translucency (often this is significantly raised and may be the result of a cystic hygroma) – see Presentation: Patient with raised nuchal translucency;
- fetal oedema (hydrops); and
- cardiac and/or renal anomalies, particularly coarctation of the aorta and/or horseshoe kidney.
- Neonatally:
- lymphoedema, with puffy hands and feet;
- webbed neck with extra skin fold crease; and
- cardiac and/or renal anomalies, particularly coarctation of the aorta and/or horseshoe kidney.
- Childhood:
- short stature;
- webbed neck and unusual habitus, with widened carrying angle and widely spaced nipples; and
- cardiac and/or renal anomalies, particularly coarctation of the aorta and/or horseshoe kidney.
- Teenage years:
- the features listed under the childhood period apply here, plus:
- no signs of puberty or absent menarche.
What do you need to do?
- Consult the National Genomic Test Directory. From here you can access the rare and inherited disease eligibility criteria, which provides information about individual tests and their associated eligibility criteria. You can also access a spreadsheet containing details of all available tests.
- For information about how to arrange testing in Wales, Scotland or Northern Ireland, see our dedicated Knowledge Hub resource.
- To find out which genes are included on different gene panels, see the NHS Genomic Medicine Service (GMS) Signed Off Panels Resource.
- Decide which of the panels best suits the needs of your patient or family.
- R26 Likely common aneuploidy: This is a common aneuploidy (QF-PCR) test that looks for trisomy 13, trisomy 18, trisomy 21 and Turner syndrome.
- R265 Chromosomal mosaicism – karyotype: This may be considered if the clinical picture is strongly suggestive of Turner Syndrome but R26 is negative. The test involves karyotyping an extended number of cells in order to identify mosaicism.
- R137 Congenital heart disease – microarray: This should be considered if you are investigating a chromosomal cause for congenital heart disease. The test looks for Turner syndrome, as well as other chromosomal causes.
- R27 Paediatric disorders: This should be considered if there is developmental delay or intellectual disability in association with congenital malformation or overgrowth, and you would like to investigate chromosomal and single-gene causes. The test is a whole genome sequencing (WGS) ‘super panel’ (a panel comprised of several different constituent panels forming one large panel).
- For tests that are undertaken using WGS, including R27, you will need to:
- complete an NHS GMS test order form with details of the affected child (proband) and their parents, including details of the phenotype (using human phenotype ontology (HPO) terms) and the appropriate panel name(s) with associated R number (see How to complete a test order form for WGS for support in completing WGS-specific forms);
- complete an NHS GMS record of discussion (RoD) form for each person being tested – for example, if you are undertaking trio testing of an affected child and their parents, you will need three RoD forms (see How to complete a record of discussion form for support); and
- submit parental samples alongside the child’s sample (this is trio testing) to aid interpretation, especially for the larger WGS panels (where this is not possible, for example because the child is in care or the parents are unavailable for testing, the child may be submitted as a singleton).
- For tests that do not include WGS, including R26, R265 and R137:
- you can use your local Genomic Laboratory Hub test order and consent (RoD) forms; and
- parental samples may be needed for interpretation of the child’s result. Parental samples can be taken alongside that of the child, and their DNA stored, or can be requested at a later date if needed.
- The majority of tests are DNA-based, and an EDTA sample (purple-topped tube) is required. Exceptions include karyotype testing and DNA repair defect testing (for chromosome breakage), which require lithium heparin (green-topped tube).
- R27 is a large WGS super panel, and requesting it currently requires authorisation from clinical genetics.
- Information about patient eligibility and test indications was correct at the time of writing. When requesting a test, please refer to the National Genomic Test Directory to confirm the right test for your patient.
Resources
For clinicians
- Genomics England: NHS Genomic Medicine Service (GMS) Signed Off Panels Resource
- NHS England: National Genomic Test Directory
- NHS Health A to Z: Turner syndrome
References:
- Gravholt CH, Viuff MH, Brun S and others. ‘Turner syndrome: mechanisms and management’. Nature Reviews Endocrinology 2019: volume 15, pages 601–614. DOI: 10.1038/s41574-019-0224-4
For patients
- NHS England: Whole genome sequencing patient information leaflets
- NHS Health A to Z: Turner syndrome
- National Organization for Rare Disorders: Turner syndrome
- Turner Syndrome Support Society