Turner Syndrome

Turner Syndrome

Definition

• Turner syndrome is a genetic disorder in females caused by partial or complete absence of one X chromosome, most commonly 45,XO

• It results in gonadal dysgenesis and oestrogen deficiency, affecting multiple systems

Pathophysiology

• Loss of genetic material from the absent or abnormal X chromosome leads to impaired ovarian development

• The degree of mosaicism influences the variability of clinical features

Presentation

• Short stature, with an average adult height around 143 cm

• Delayed puberty and primary amenorrhoea due to gonadal failure

• Characteristic physical features include a webbed neck, low hairline, and extra skin on the neck

• Broad chest with widely spaced nipples is typical

• Congenital cardiac anomalies such as coarctation of the aorta and bicuspid aortic valve

• Additional features may include puffy hands and feet, and subtle skeletal abnormalities

• Learning difficulties, particularly with spatial awareness and mathematics, may be present

Diagnosis

• Confirm diagnosis with karyotype analysis, showing 45,XO or mosaicism

• Elevated FSH and LH levels indicating gonadal failure

• Low oestradiol levels consistent with oestrogen deficiency

• Cardiac screening and endocrine evaluations are recommended as part of the workup

Management

• Initiate growth hormone therapy in childhood to optimise final adult height

• Begin oestrogen replacement therapy to induce puberty and maintain bone health, continuing until the age of natural menopause

• Regular cardiovascular monitoring, including echocardiography and blood pressure assessment, to detect congenital heart disease and hypertension

• Provide psychosocial support and counselling to address learning, social and emotional challenges

• Offer multidisciplinary follow-up involving endocrinologists, cardiologists and genetic counsellors

• Contraceptive counselling is essential, as HRT is not contraceptive

Notes

• Turner syndrome may be diagnosed prenatally via amniocentesis or CVS, or later in childhood/adolescence based on growth failure and pubertal delay

• Fertility is significantly impaired; spontaneous ovarian function is rare, and assisted reproductive techniques may be required

• Early intervention with growth hormone and timely initiation of HRT are key to improving long-term outcomes

• Ongoing monitoring for cardiovascular, metabolic and skeletal complications is essential throughout life

• A multidisciplinary approach ensures comprehensive management and supports overall quality of life