Turner syndrome

Turner syndrome (TS), commonly referred to as 45,X or 45,X0, is a hereditary condition in which a female lacks either all or part of her X chromosome. It is also called by the term known as congenital ovarian hypoplasia. Turner syndrome often does not run in families, rather, it develops during the production of a parent's reproductive cells or during the first cell division stage of development. There is no role for environmental factors in its development, and mother's age also has no significant effect. When the chromosomal aberration only affects a small number of cells, it is referred to as Turner syndrome with mosaicism. Mostly there would not be any symptoms in this condition, but in some cases fewer symptoms might be seen. Even though the disease is typically detected at an advanced stage, it is crucial to diagnose girls with Turner syndrome as soon as possible in order to manage the condition. Early disease detection is largely achieved through prenatal diagnostics.

A genetic disorder affecting only females & causes a wide range of abnormalities such as short stature, & delayed puberty.

Symptoms

Turner's syndrome has a wide range of symptoms that vary with age. The predominant symptoms include:

• accumulation of fluid (lymph) in the extremities that develops early in life

• abnormal growth of the nails

• folding of the skin is seen in the lateral aspect of  the neck (webbed neck)

• short stature

• broad chest with extensively spaced nipples (shield chest)

• short fourth metacarpals or metatarsals

• narrow, high-arched palate

• deformity in the elbow (cubitus valgus)

• Deformity at the base of the neck with  a low hairline a low hairline  

• genetic defects in the development of the ovaries

• delayed puberty and infertility

• reduction in the secretion of sex hormones by gonads

• narrowing of the aorta

• impairment of cognitive function

• heart anomalies acquired at birth like congenital heart disease

• diabetes mellitus (type I and II)

• disorders of the autoimmune system like osteoporosis

Diagnosis

1. The diagnosis of Turner's syndrome can be done both prenatally and postnatally. Amniocentesis (removal of amniotic fluid for testing) or chorionic-villus sampling (biopsy of the placental tissue) are the methods used to detect Turner's syndrome before birth.

2. The mother's womb should be checked for physical signs such as fetal hydrops (severe swelling during the fetal stage), cardiac defects, or a cystic hygroma (a fluid-filled sac caused by a blockage in the lymphatic system), and if they are present, karyotype testing should be done to rule out Turner's syndrome.

3. Karyotype testing involves looking at all of the chromosomes that are present in the patient's cells to see if they are abnormal. It is recommended to use peripheral blood mononuclear cells for a karyotype study.

4. Occasionally, in Turner syndrome mosaicism cases, the karyotype may appear normal. In those cases, fluorescence in situ hybridization (FISH) can be carried out if there is a strong suspicion despite normal karyotype testing from various tissues. FISH can reveal irregularities in even a small portion of the DNA sequence or chromosomes.

5. After-birth diagnoses can be made by observing the typical clinical symptoms of delayed puberty onset in adolescent patients. Examining the level of follicle-stimulating hormone (FSH), is the laboratory test that can be done to confirm the existence of Turner syndrome. It is elevated in this condition.

6. Defect in the ovaries leading to failure in secreting the hormones is the characteristic feature of this syndrome. This feature can be better assessed by n anti-Mullerian hormone test ( test that measures the levels of AMH).

Management

There is no cure for Turner's syndrome. The patient should be given symptomatic treatment to reduce its severity. The following are the different types of treatments that are done to reduce the symptoms of this syndrome:

• Treatment of short height in Turner syndrome-affected girls can be done with growth hormone therapy in an early age.

• Surgical correction can be done for coarctation of  the aorta( a birth condition characterised by a narrower-than-normal aorta). Cardiovascular MRI or an echocardiography are continuously used to monitor individuals for aortic dilatation throughout their lives.

• Beta-blockers and ACE inhibitors should be used to control blood pressure , and patients should be closely watched to reduce the risk of aortic dilatation and dissection.

• If no breast development occurs by the ages of 11 to 12 years, estrogen replacement therapy should be started.

• Through their whole lifespan, Turner syndrome patients should receive serial audiology assessments, which are advised to be performed every three years in children and every five years in adults. In high-risk hearing disability groups, intensive patient education, immunizations, and antibiotic therapy are advised.

• In case of any abnormalities in the renal system, the patient should be referred to a nephrologist for a complete renal assessment.

• Oestrogen therapy, as well as extra calcium and vitamin D, can be administered to reduce the risk of bone mineral density degeneration.

• Patients should be encouraged to engage in physical activity and quit undesirable habits like smoking by providing them medical counselling as well as integrative therapy guidance.

• There is little information available regarding the incidence and management of severe scoliosis and other spinal deformities in Turner's syndrome (TS) patients. These patients' spinal curvature improved to some extent following posterior spinal fusion (PSF) therapy without any problems.

Knowing the clinical and genetic features of Turner's syndrome is crucial for prompt case discovery and effective therapy of the co-morbidities linked to this inherited disorder.