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Madisons Foundation - Moms And Dads In Search Of Needed Support
Turner Syndrome (TS)
Sunday, 14 August 2005
Last Updated Sunday, 14 August 2005
What
Turner Syndrome (TS) is a genetic condition caused by the absence of a portion or all of one of the X chromosomes in a person’s cells. Turner syndrome patients are female and usually have a characteristic physical appearance (also known as “phenotype”) that includes short stature, immature internal sexual organs and lack of signs of external sexual maturity (to be discussed in further detail in “Signs & Symptoms).Who
Turner Syndrome is only present in females, and it occurs in about 1 out of 2,500 live births. In the United States, there are approximately 50,000-75,000 females with Turner Syndrome. The incidence does not vary among ethnic groups.Signs and Symptoms
Naturally, the phenotype (physical appearance) of the individual often leads to the diagnosis of Turner Syndrome. The diagnosis can be made at any age, including before birth. There may be suspicion of Turner Syndrome before an infant is born if on prenatal ultrasound there is evidence of thickened neck folds which later progress to a webbed neck; nuchal cystic hygromas which are collections of fluid in the neck; or a short femur (upper leg bone). In infancy and in young children, characteristics which may be suggestive of Turner Syndrome include: slow growth with short stature and poor weight gain; loose neck skin (pterygium colli) and/or swelling of the hands and feet; flattened midsection of the face and redundant skin around the eyes; high-arching palate; low-set hairline; wide-spaced nipples; heart problems (including a heart murmur from aortic stenosis or bicuspid aortic valve or decreased lower body pulses from aortic coarctation); and structural problems with the kidneys including abnormal shape or location. Sometimes girls with Turner Syndrome go undiagnosed until the teen years when they fail to undergo the normal adolescent growth spurt and do not undergo usual pubertal development. Lacking ovaries, they do not usually develop breasts. Although many girls with Turner Syndrome will not begin having their menstrual cycle due to immature ovaries, a small number do have enough ovarian development to have periods (menarche). In adulthood, there are signs of osteopenia (poor bone mineralization) or osteoporosis due to lack of hormonal stimulation from immature ovaries.Possible Causes
Turner Syndrome is caused by the absence of a portion or all of one of the X chromosomes, and this variation gives way to the variety of physical presentations. Usually a person has 23 pairs of chromosomes (a total of 46), one set of which is the sex chromosomes. In most patients with Turner Syndrome their genetic make-up is designated as 45,X which indicates that one of the X chromosomes is absent. It is uncertain why the X chromosome is not inherited in these cases but does not appear to be related to maternal age. About 30-40% of girls with Turner Syndrome actually have a mixture of 45,X chromosomes and normal cells with both chromosomes present (46,XX). This is referred to as mosaicism, and the severity of Turner Syndrome in these patients depends on the proportion of affected cells.Diagnosis
Although physical characteristics may suggest Turner Syndrome, the diagnosis requires examining the patient’s chromosomes from either blood or skin cells using a karyotype. A karyotype a picture of a person’s chromosomes. To evaluate for the presence and development of internal sexual organs, a pelvic or abdominal ultrasound may be used. Some girls may have undergone a work-up for short stature or lack of menstrual periods prior to officially being diagnosed with Turner Syndrome via the karyotype.Treatment
Because Turner Syndrome involves many different parts of the body, the child will usually have more than one doctor. There will be a primary care doctor as well as specialists who focus on more specific issues such as the heart, kidneys, and endocrine system (lack of menstrual periods, thyroid concerns, and slow growth). Other specific concerns for which the children may receive special care include developmental delays and learning disabilities. As short stature is one of the most characteristic features of Turner Syndrome, research has been done using recombinant human growth hormone therapy to help increase height. This therapy has been shown to be effective in most but not all children with some reaching normal adult height after therapy. Some doctors believe that growth hormone treatment should be started in early childhood, while other doctors believe in waiting until there is evidence of slow growth before starting therapy. Estrogen replacement therapy is sometimes started in early adolescence (around 13-14 years old) to help with puberty; however, there is some discrepancy as to the best age at which to start this therapy. The psychological preparedness of the child and her family to accept therapy must be taken into account. As exposure to estrogen can lead to decreased growth, the timing of starting estrogen therapy needs to be coordinated with growth hormone therapy. Estrogen also may provide some benefit in terms of cognitive and motor function and also long-term benefit in preventing osteoporosis. Concerns about fertility may be raised as the child ages. Some experts believe it is best to advise the child between the age of 8 and adolescence that she will probably not have children. However, successful pregnancies have been carried to term using egg donation and in vitro fertilization. If learning disabilities are suspected, further testing to evaluate intelligence, aptitude, behavior, and emotional reactions should be performed as early as possible to provide the most support available. Girls with Turner Syndrome have been shown to have trouble with spatial relationships leading to more difficulty with tasks such as driving and math problems.Prognosis
Although puberty concerns and growth problems tend to be some of the more noticeable components of Turner Syndrome, it is important to realize that the child may have additional medical concerns which need to be addressed in order to live a healthy life. In the absence of severe heart defects at birth, most girls with Turner Syndrome survive into adulthood and have normal intelligence. About 2-5% of women with Turner syndrome have some ovarian function and may spontaneously start menstruating. As mentioned above in “Treatment,” methods such as in-vitro fertilization and embryo transfer have assisted women with Turner Syndrome in becoming pregnant. As with many childhood diseases, psychological problems may result from the stigma associated with the condition and its symptoms, especially considering that teenagers with Turner Syndrome will not physically mature like their peers. These issues should be addressed early on to minimize long-term effects on emotional development and overall health and wellness. In adults with Turner Syndrome, it is important to monitor for high cholesterol, osteoporosis, thyroid problems, obesity, elevated blood pressure, and diabetes mellitus. These are best addressed by routine healthcare, and early intervention provides the best prognosis. Many females with Turner Syndrome lead relatively normal lives, although coupled with long-term health management.Connect with other parents
In the spirit of community and support, Madisons Foundation offers the unique service of connecting parents of children with rare diseases. If you would like to be connected to other parents of children with this disease, please fill out this brief form.Weblinks
Turner Syndrome Society of the United States
A great website committed to providing support to individuals with Turner Syndrome, as well as advancing research into this condition and promoting education and learning. Links are provided to connect patients and their families with local chapters.
Turner Syndrome
This site does a thorough job in explaining some of the basics of Turner Syndrome. It includes a diagram of a karyotype and illustrates the abnormality involving the sex chromosomes (the 23rd pair). It also provides information on ongoing clinical trials.
Turner Syndrome Support Society
A great site which is dedicated to providing support for anyone affected by the Syndrome. Additional website links are provided.
National Institute of Child Health and Development
This site provides general information about Turner syndrome, as well as sharing information about clinical studies of Turner Syndrome being conducted at the NIH.