This is a rare genetic disorder that affects several parts of the body that include the heart, skin, hair and the face. Several genes are identified to be the cause of this syndrome which mostly develops as the result of new genetic mutation. As this is a rare condition, the real prevalence among the population is not known but is estimated that around 200 to 300 individuals globally are affected.
Causes
Cardiofaciocutaneous syndrome is believed to be the result of a new genetic mutation with no history of its presence in the affected individual’s family. However, few cases were reported to be inherited in an autosomal dominant pattern meaning one copy of the defective gene in each cell is sufficient to cause this condition. Mutation in the gene BRAF accounts for 75 to 80% of all the cases, 10 to 15% is the result of a genetic mutation in one of the two genes; MAP2K1 and MAP2K2 and defect in the gene KRAS affects 5% of the cases. All these genes are responsible for the chemical signalling pathway that is vital for the healthy development of the fetus. The mutation in any one of this gene can affect the chemical signalling process which interferes with the normal development process of tissues and organs resulting in the features that are characteristics of this condition.
Symptoms
The infants present feeding difficulties, weak muscle tone (hypotonia), inability to gain weight, large head (macrocephaly), exhibiting delayed development and may be short in stature. The distinct facial features can include a high forehead, widely spaced eyes, droopy eyelids, low-set ears and downward pointed outer corner of the eyes. The curly scalp hair may be dry or brittle, inadequate or lack of eyebrows and eyelashes, skin that is rough or abnormally dry, moles called nevi and a skin condition known as keratosis pilaris which presents small bumps on the limbs and the face. The congenital heart condition is evident in about 77% of the cases that can include abnormal heart rhythm, thickening of the heart muscle (cardiomyopathy), impaired heart values that causes problems with blood flow to the lungs (pulmonic stenosis) and an abnormal opening in a section of the heart that divides the upper chambers (atrial septal defects). The endocrine problems can include growth hormone deficiency along with early puberty. The additional abnormalities can consist of urogenital anomalies, undescended testes in males (cryptorchidism) and webbed neck.
Diagnosis
The diagnosis is based on identifying the features associated with this syndrome and in confirming it with various clinical examinations. Some of the tests to detect abnormality of the heart include the echocardiography, electrocardiography, cardiac catheterization and x-rays. The respiratory functions may also be evaluated along with a CT scan to assess the degeneration of the brain’s outer layer and electroencephalograph to monitor the brain’s electrical impulses if seizures are suspected. To determine any abnormalities of the eyes various diagnostic tests may be necessary and can include ophthalmoscopy that visualizes the inside of the eyes. Additional tests can include a complete abdominal ultrasound to determine the presence of any anomalies of the urogenital system, dermatologic evaluation and endocrine assessment when the problem with growth occurs.
Treatment
The treatment for this syndrome usually focuses on treating the various symptoms that are evident in each person. The congenital heart abnormalities may require medications or surgery to correct the defects. The respiratory infections are treated with antibiotics and anticonvulsant medications to treat or prevent seizures. Children with feeding difficulties may require feeding tubes and abnormalities of the eyes may be corrected with glasses, lenses or surgery to improve vision. The skin conditions may require ointments such as petroleum jelly to keep the skin moist. The other forms of treatments includes speech therapy, occupational therapy and special remedial education.
References
https://rarediseases.org/rare-diseases/cardiofaciocutaneous-syndrome/
https://ghr.nlm.nih.gov/condition/cardiofaciocutaneous-syndrome#genes
