NS
With special care and counselling, the majority of children with NS will grow up and function normally in the adult world. Management should address feeding problems in early childhood, evaluation of cardiac function and assessment of growth and motor development. Physiotherapy and/or speech therapy should be offered if indicated. A complete eye examination and hearing evaluation should be performed during the first few years of schooling. Preoperative coagulation studies are indicated. Signs and symptoms lessen with age and most adults with NS do not require special medical care.
Associated disease
Complications
Spontaneous chylothorax (a type of pleural effusion, results from lymph formed in the digestive system called chyle accumulating in the pleural cavity due to either disruption or obstruction of the thoracic duct) may occur in childhood and chylous effusion is a known complication of cardiac surgery and surgery for thoracic deformity.
Hearing loss due to otitis media is also a frequent complication.
Risk factors
New medical problems are not expected to appear in adulthood. However, males who were born with undescended testes may have fertility problems due to azoospermia (a man not having any measurable level of sperm in his semen).
In the past, men with azoospermia were classified as infertile, and a sperm donor was initially considered one of the best options for conceiving. Currently, the knowledge that many causes of azoospermia can be reversed is widespread in the medical literature and practice. Thus, any trusted specialized assisted reproductive center will request a urologist/andrologist to provide sperm for an ART procedure.
There is no evidence for gynaecological or childbearing complications in females with NS.
Preimplantation genetic diagnosis (PGD) allows genetic diagnosis of embryos in very early stages, with the purpose of avoiding the transmission of genetic diseases to offspring. PGD represents an alternative to prenatal diagnosis and termination of pregnancy, in couples at risk of transmitting these disorders.
Symptoms of Noonan syndrome may include the following:
Heart
Up to ~85% of people with NS have one of the following heart defects:
Lungs
Genito-urinary system
Stature
Lymphatic system
Musculoskeletal
Neurological
Eyes
Ears and hearing
There is no self therapy for Noonan syndrome.
The majority of children with NS will grow up and function normally in the adult world. However, they need special care and counselling. Familiarity with the characteristic features of NS is clearly important for clinical geneticists, cardiologists, surgeons, anaesthetists, gynaecologists, paediatricians and dermatologists.
Pharmacotherapy
Growth hormone (GH)
Short stature is a frequent feature of Noonan syndrome (NS), a disease caused by mutations of genes encoding components protein signalling pathway. To date numerous patients have been treated with growth hormone (GH) in various countries. However this treatment is still controversial, as its efficacy is a matter of debate. The final height gain of GH therapy represents 5 to 10 cm, at best, which is disappointing considering the length and burden of the treatment.
Surgical therapy
There is no surgical therapy for this condition.
Assisted reproductive technology (ART) is the technology used to achieve pregnancy in procedures such as fertility medication, artificial insemination, in vitro fertilization and surrogacy. Some forms of ART are also used with regard to fertile couples for genetic reasons (preimplantation genetic diagnosis).
Among women with older reproductive age, with history of repetitive abortions or genetic disorders, genetic analysis is highly recommended. The PGS/PGD allows studying the DNA of eggs or embryos to select those that carry certain damaging characteristics. It is useful when there are previous chromosomal or genetic disorders in the family, within the context of in vitro fertilization programs.
Men with cryptorchidism had a good chance of sperm retrieval when undergoing micro-TESE (testicular sper extraction). The concept of micro-TESE is to identify the areas of probable sperm production within the testes based on the size and appearance of the seminiferous tubules, with the aid of optical magnification. Micro-TESE is advocated to be more efficient to other methods of sperm acquisition, such as TESE and Testicular Sperm Aspiration (TESA). The reasons are the greater success in obtaining sperm and lower tissue removal that facilitates sperm processing and lessens testicular damage.
In fact, cryptorchid men tended to have slightly higher sperm retrieval rates relative to all other men with nonobstructive azoospermia, although the difference in pregnancy rates was not statistically significant. In men with cryptorchidism, there is a correlation with both testicular volume and age at orchiopexy (a surgery to move an undescended testicle into the scrotum and permanently fix it there).
If all efforts to extract vital sperm cells fails, then donated ones may be recommended.
The inability (that lasts more than 6 months) to develop or maintain an erection of the penis during sexual activity.
A medical term which describes a diminished functional activity of the gonads – the testes and ovaries.
Decrease of facial and body hair in males.
Process by which a woman donates eggs for purposes of assisted reproduction or biomedical research.
A micromanipulative fertilization technique in which a single sperm is injected directly into an egg.
The procedure in which a man (sperm donor) provides his sperm for fertility treatment.
A process in which an egg is fertilised by sperm outside the body: in vitro. Own or donated gametes may be used.
