Turner syndrome is characterised by gonadal dysgenesis and short stature. The diagnosis is confirmed with the karyotype 45 XO, though mosaicism is common.
The main presenting feature could be short stature, absent or delayed puberty, or primary or secondary amenorrhoea. Alternatively, the patient may be seeking fertility.
Detailed history, including pubertal development, is mandatory in all patients as this may reduce the differential diagnoses considerably.
Specific lines of questioning are indicated according to the exact problem (see below).
Check whether the patient is known to have any cardiac or renal abnormalities. There is also an increased risk of deafness, thyroid dysfunction and coeliac disease.
Puberty before 8 years in girls is likely to be precocious and further assessment is necessary. Between 8-13 years most girls will be either ‘Prepuberty’ or ‘In puberty’. If there are no signs of puberty by 13 years, then puberty is delayed and further assessment is indicated. From 13-16 years most girls will be either ‘In puberty’ or ‘Completing puberty’. After 16 years girls will usually be ‘Completing puberty’. If this is not the case, maturation is delayed and further assessment is required.
Puberty before 9 years in boys is likely to be precocious and further assessment is necessary. Between 9-14 years most boys will be either ‘Pre- puberty’ or ‘In puberty’. If there are no signs of puberty by 14 years, then puberty is delayed and further assessment is indicated. From 14-17 years most boys will be either ‘In puberty’ or ‘Completing puberty’. After 17 years boys will usually be ‘Completing puberty’. If this is not the case, maturation is delayed and further assessment may be needed.
Girls with Turner mosaicism generally have a milder phenotype and may undergo apparently normal pubertal development, but then present with secondary amenorrhoea.
Some patients with Turner mosaicism will present with secondary amenorrhoea. However, other differential diagnoses should be considered in such patients, for example polycystic ovarian syndrome as well as hyperprolactinaemia and thyroid dysfunction (see below).
Various auditory problems are very common in patients with Turner syndrome.
High arched palate is more common in Turner syndrome and may cause feeding problems at birth.
Dental hypoplasia is associated with Kallmann's syndrome which also presents with hypogonadism, and micrognathia may occur in Turner syndrome leading to orthodontic problems.
Hypertension and coarctation of the aorta are both associated with Turner syndrome. Other cardiac abnormalities may also occur.
Anatomical abnormalities of the urogenital tract is commonly associated with Turner syndrome.
Thyroid dysfunction is commonly associated with Turner syndrome.
Diabetes has an increased incidence in Turner syndrome.
Various medications can interfere with the hypothalamic-pituitary-gonadal function.
Patients presenting with hypogonadotropic hypogonadism should be assessed for other possible causes unless the diagnosis of Turner syndrome has been confirmed.
Anorexia nervosa and very low BMI of any cause may result in hypothalamic dysfunction.
Soya is known to contain large amounts of phytoestrogens which may interfere with the hypothalamic-pituitary-gonadal axis. Steroids also interact with the hypothalamo-pituitary-gonadal axis and may occasionally be found in preparations thought by the patient to be 'natural' or 'herbal'.
Problems of coordination are common in girls with Turner syndrome.