Jana was brought in by her parents to see the GP because she was almost sixteen and had not yet had commenced menstruation. Jana had no medical problems and otherwise appeared normal. The GP noted that the girl was significantly shorter than her mother and was slight in build. On examination, Jana had sparse axillary hair and would not have needed to shave very often. Her breasts were small and her nipples were under developed. The GP initially organised a transabdominal pelvic ultrasound and this showed absence of the ovaries and an unusually small uterus, even for a pre-pubertal teenager. The GP arranged a referral to a Paediatric endocrinologist and Turner Syndrome was diagnosed.
Turner’s Syndrome is the genetic absence of the second X chromosome (or part of it) and so instead of being 46XX, the individual is 45X0 (non-dysjunction). Rarely, the condition may be mosaic (some cells have normal XX chromosomes, some have 45X0), may be caused by a translocation and/or partial deletion of one X chromosome. Turner Syndrome occurs in approximately one in 2,000 births in Australia.1
The most common signs of the condition are infertility, reduced total height, absent menstruation and a reduction in secondary sexual characteristics, such as pubic hair and breast development. Intelligence is usually normal but there may be some impairment in spatial ability and non-verbal learning. There is an increased incidence of congenital heart disease, especially coarctation of the aorta and aortic valve abnormalities, which occur in a significant number of individuals with the condition.1 There may also be an increased carrying angle at the elbow (cubitus valgus). There is a great deal of variation in the clinical presentation of Turner Syndrome.
It is important for GPs to be aware of some of the signs of Turner syndrome that may suggest the diagnosis before delayed puberty is suspected. These include short stature in childhood, puffiness of hands and feet, a low hairline at the back of the neck and loose skin folds around the neck. Hormonal therapy is required to bring on puberty in the vast majority of these girls and usually the oral contraceptive is used to support secondary sexual characteristics and to avoid the development of osteoporosis.
1. Centre for Genetics Education. Fact Sheet 40: Turner Syndrome, NSW Government, 8 December 2015
2. Turner Syndrome Association of Australia