Turner Syndrome Explained: Causes, Symptoms, Diagnosis and Treatment

What is Turner Syndrome?

Turner syndrome is a rare genetic disorder that affects only females and occurs when one of the two X chromosomes, which controls growth and development, is missing or incomplete. Since the chromosomes carry essential information for the body, this can affect height, features, and organs, and the body systems that are impacted are generally related to the heart and reproductive system.

Turner syndrome is present from birth, and it has variable effects in individuals. Some features of Turner syndrome will present at infancy while other effects will appear in puberty. Turner syndrome cannot be prevented, but early understanding of Turner syndrome and good medical care will enable girls and women with Turner syndrome to live healthy, meaningful lives, reach their goals and dreams, and engage fully in schools, work, friendships, and everyday life.

What Causes Turner Syndrome?

Turner syndrome is not caused by anything a parent did or did not do during pregnancy. It happens by chance when one of the two X chromosomes in a female’s genetic makeup is missing or incomplete. This change can occur in every cell of the body, or in just some cells – a pattern known as mosaic Turner syndrome. Chromosomes carry the instructions that guide our growth and development, so when one is missing or altered, it can affect height, physical traits, and certain aspects of health. Turner syndrome is present from the very start of life, but it is not inherited in most cases. Because it occurs randomly, there is currently no known way to prevent it.

Turner Syndrome | Symptoms

Turner syndrome can affect each person differently, and some signs may be noticed right after birth, while others appear later in childhood or adulthood. Not everyone will have all of these features, but some common ones include:

Because features vary, regular medical check-ups are important for timely support.

How Is Turner Syndrome Diagnosed?

Turner syndrome, a genetic condition caused by the partial or complete absence of one X chromosome in females, can be identified either before or after birth through various diagnostic methods. Early detection is crucial as it enables healthcare providers to develop a tailored care plan that supports the child’s growth, development, and long-term health outcomes. Below is a detailed overview of the diagnostic process.

Prenatal Diagnosis

During pregnancy, Turner syndrome may be suspected based on specific findings observed through routine prenatal screening. These methods are not definitive but can indicate the need for further testing:

• Ultrasound Findings: A routine ultrasound may reveal physical signs suggestive of Turner syndrome, such as lymphedema (swelling around the neck or other areas due to fluid buildup), cystic hygroma (a fluid-filled sac), or abnormalities in the heart or kidneys. These findings are not specific to Turner syndrome but may prompt further investigation.

• Non-Invasive Prenatal Testing (NIPT): NIPT is a screening tool that analyses cell-free fetal DNA circulating in the mother’s blood. This test, typically performed after 10 weeks of pregnancy, can detect chromosomal abnormalities, including those associated with Turner syndrome (e.g., monosomy X). NIPT is highly sensitive but not diagnostic, meaning a positive result requires confirmation with more invasive tests.

• Invasive Diagnostic Tests: If screening tests suggest a chromosomal abnormality, doctors may recommend invasive procedures to confirm the diagnosis:

  • Amniocentesis: This procedure, usually performed between 15 and 20 weeks of pregnancy, involves extracting a small sample of amniotic fluid surrounding the fetus. The fluid contains fetal cells, which are analysed to examine the baby’s chromosomes for abnormalities, such as a missing or altered X chromosome.

  • Chorionic Villus Sampling (CVS): Conducted between 10 and 13 weeks of pregnancy, CVS involves taking a sample of placental tissue (chorionic villi) to analyze the fetus’s genetic makeup. Like amniocentesis, CVS can confirm the presence of Turner syndrome by identifying chromosomal irregularities.

Postnatal Diagnosis

If Turner syndrome is not detected during pregnancy, it may be diagnosed after birth, often due to physical features, growth delays, or health concerns. The primary method for confirming Turner syndrome postnatally is:

• Karyotype Test: A karyotype test is the gold standard for diagnosing Turner syndrome. This blood test examines the number and structure of a person’s chromosomes. In Turner syndrome, the karyotype typically reveals a complete or partial absence of one X chromosome (e.g., 45,X instead of the usual 46,XX in females). Variations, such as mosaic Turner syndrome (where only some cells have an abnormal chromosome count), can also be identified through this test.

Importance of Early Diagnosis

Identifying Turner syndrome as early as possible is critical for several reasons:

• Tailored Care Plans: Early diagnosis allows healthcare teams to create individualised treatment plans that address the child’s specific needs, such as growth hormone therapy or monitoring for associated health conditions.

• Support for Growth and Development: Early interventions can promote healthy physical and emotional development, potentially mitigating challenges like short stature or delayed puberty.

• Family Support: A timely diagnosis provides families with the information and resources they need to understand the condition, make informed decisions, and access support networks, fostering confidence and reassurance.

Treatment Options for Turner Syndrome

While there is no cure for Turner syndrome, a range of treatments can effectively manage symptoms, support healthy development, and improve quality of life. Treatment plans are highly individualised, depending on the person’s specific symptoms and health needs. A multidisciplinary team, including endocrinologists, cardiologists, and other specialists, often oversees care. Below are the primary treatment approaches:

Hormone Therapy

Hormone therapy is a cornerstone of treatment for Turner syndrome, addressing growth, puberty, and long-term health.

• Growth Hormone Therapy: Many girls with Turner syndrome experience short stature due to the condition’s impact on growth. Growth hormone therapy, typically administered through daily injections, can help increase height when started early in childhood (often around ages 4–6). The therapy stimulates bone growth, potentially allowing girls to reach a height closer to their peers. Regular monitoring by an endocrinologist ensures the therapy is effective and safe.

• Estrogen Therapy: Most girls with Turner syndrome do not undergo spontaneous puberty due to ovarian dysfunction. Estrogen therapy, usually initiated in the early teenage years (around ages 11–14), supports the development of secondary sexual characteristics, such as breast development, and promotes healthy bone growth, cardiovascular health, and the onset of menstrual cycles. Estrogen is typically administered as a patch, gel, or oral medication, with doses gradually increased to mimic natural puberty.

• Progestin Therapy: After estrogen therapy has been established, progestin is often introduced to regulate the menstrual cycle and induce a more typical pattern of periods. This combination therapy (estrogen and progestin) also supports uterine health and reduces the risk of complications, such as endometrial hyperplasia, in those with a uterus.

Ongoing Monitoring and Management

Turner syndrome is associated with an increased risk of health issues affecting the heart, kidneys, thyroid, ears, and other systems. Regular monitoring is essential to detect and manage these conditions early, ensuring individuals lead active, healthy lives. Key aspects of ongoing care include:

• Cardiovascular Monitoring: Up to 50% of individuals with Turner syndrome have congenital heart defects, such as bicuspid aortic valve or coarctation of the aorta. Regular echocardiograms or MRIs help monitor heart health and guide interventions if needed.

• Kidney Surveillance: Structural kidney abnormalities, such as horseshoe kidney, are common in Turner syndrome. Regular imaging, such as ultrasounds, ensures proper kidney function and early detection of issues.

• Hearing Assessments: Hearing loss, often due to recurrent ear infections or sensorineural issues, affects many individuals with Turner syndrome. Routine hearing tests allow for timely interventions, such as hearing aids, if necessary.

• Thyroid and Bone Health: Regular blood tests monitor thyroid function, as hypothyroidism is common. Bone density scans may also be recommended to assess bone strength, especially since estrogen therapy plays a critical role in maintaining bone health.

• Psychosocial Support: Turner syndrome can impact emotional and social well-being due to physical differences or fertility challenges. Counselling or support groups can provide valuable emotional support for individuals and families.

Importance of Comprehensive Care

Without appropriate treatment and monitoring, individuals with Turner syndrome may face challenges such as severe short stature, delayed or absent puberty, infertility, or complications from untreated heart or kidney issues. However, with early and consistent interventions, most women with Turner syndrome can lead active, fulfilling lives. Regular follow-ups with a healthcare team ensure that treatments are adjusted as needed and that any emerging health concerns are addressed promptly.

Treatment Options

While there is no cure for Turner syndrome, a range of treatments can help manage symptoms, support healthy development, and address related health concerns. Care is often personalised, with a focus on hormone therapy.

• Growth hormone therapy may be recommended in childhood to help increase height, especially when started early.

• Oestrogen therapy is usually introduced during the teenage years to support the changes of puberty, such as breast development, menstrual cycles, bone strength, and heart health.

• Adding progestin therapy later to develop a more typical menstrual cycle pattern.

If left unchecked, using these treatments cannot help to develop an active monitoring routine for heart, kidneys, hearing, and other organ status. Thus, women with Turner syndrome will not be able to lead active, healthy lives.

Conclusion

Turner syndrome is just one piece of a person’s puzzle; it does not define who they are or what they can do. The condition may cause difficulties, including health issues, but combined with early diagnosis, routine follow-ups, and appropriate treatment, it is possible to maintain health and support your growth. If you or your child has Turner syndrome, being informed and keeping an open dialogue with your healthcare team will enable you to feel comfortable managing the condition and focusing on what is important: the future that is full of possibilities, opportunities, and successes for you as an individual.

If you are showing signs of Turner syndrome, consult our expert specialists at Manipal Hospitals for early diagnosis and personalised treatment plans.