| Turner syndrome is a chromosomal disorder that can cause girls to have short stature, a failure to begin puberty and infertility. Children with Turner syndrome only have one functioning X chromosome (unlike normal females who have two functioning X chromosomes [46, X, X]), and the other one may be absent [45, X] in all cells, or just some cells which is called a mosaic [45, X/46, X, X], or there may be a fragment of the second X chromosome present in some cells.
It is not known what causes Turner syndrome and it is not associated with advanced maternal age. Turner syndrome is found in about 1 out of every 2000-3000 live born females.
Other manifestations of Turner syndrome can include having a webbed neck (extra skin folds at the base of the neck), broad chest with widely spaced nipples, lymphedema (puffiness over the fingers and toes), a low posterior hair line, small jaw, prominent ears, a short 4th finger and/or toe, sensorineural hearing impairment, vision problems (strabismus, amblyopia, ptosis), developmental hip dysplasia, obesity, kidney abnormalities (including horseshoe kidney), scoliosis, heart defects and high blood pressure, keloid formation, and mild delays in motor development and early language development, but they usually have normal intelligence.
Many other children with Turner syndrome just have short stature and a failure to begin puberty and have their first period. It is often when a child fails to begin puberty that they are suspected of having Turner syndrome. Or it may be found even later in women evaluated for infertility. Some children are diagnosed prenatally, when prenatal chromosome analysis by chorionic villous sampling or amniocentesis is done for a high risk pregnancy.
Although often small at birth, young children with Turner syndrome usually grow normally until they are about three years old. They then have a decrease in their rate of growth or growth velocity that is less than the usual growth rate of 6 cm/year, and have short stature as compared to other children of the same age. Girls with Turner syndrome also do not begin sexual maturation or puberty as expected, which would be by 13 years of age, although some (10-20%) do have breast development and a smaller percentage have periods.
Among the tests that are commonly performed to evaluate the growth of a child with short stature include determining a bone age, which is the chronological age of your child's bones.
Other tests can include blood tests to check the child's karyotype (number and type of chromosomes) to specifically check for Turner syndrome, gonadptropin levels (FSH and LH), thyroid hormone levels to check for hypothyroidism (T4 and TSH), growth hormone levels (usually by checking IGF-1 and IGF BP3), complete blood counts (CBC to check for anemia), blood chemistries (which can include a SMA 20 to check for liver and liver disease), and a urinalysis.
If your child is diagnosed with Turner syndrome, then she will probably also have an ultrasound of her heart, kidneys and ovaries to look for associated abnormalities and periodic testing of her thyroid hormone levels because of an increased risk of hypothyroidism.
Treatments, usually by a Pediatric Endocrinologist, may include growth hormone replacement, which can increase the final adult height in some children with Turner syndrome and/or treatments with anabolic steroids (oxandrolone). Other treatments include estrogen replacement at the appropriate age, but it is controversial as to when is the best time to start (early at 12-13 years of age vs. later at 14-15 years). Estrogen replacement can help your child to develop secondary sexual characteristics and have periods.
While there are occasional reports of girls with Turner syndrome becoming pregnant, most will require fertility treatments and oocyte or embryo donation and implantation.
Children with Turner syndrome may also benefit from participating in a Turner syndrome support group or counseling.
Growth Disorder Resources:
- The Magic Foundation: "Major Aspects of Growth In Children for Children's Growth and Related Adult Disorders," a nonprofit organization providing support and education regarding growth disorders in children and related adult disorders, including adult growth hormone deficiency.
- Turner Syndrome Society of the US: "a nonprofit organization whose mission is to: Increase public awareness and understanding of Turner Syndrome; Increase understanding of those affected by Turner Syndrome about the condition and its associated problems; Provide a forum where those affected by Turner Syndrome can become acquainted with others in similar situations."
- Health Supervision for Children with Turner Syndrome: policy statement from the American Academy of Pediatrics with guidelines for physicians treating children with Turner syndrome, with a special Turner syndrome growth chart.
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