Trisomy 18

Trisomy 18, also known as Edwards syndrome, is a rare genetic disorder caused by an extra copy of chromosome 18. This condition occurs when there is an error in cell division during the formation of reproductive cells or in early fetal development, resulting in an extra chromosome 18.

Causes and Risk Factors

The exact cause of Trisomy 18 is not known, but it is thought to be related to advanced maternal age. Women over the age of 35 are at a higher risk of having a child with Trisomy 18. The condition can also occur in families with no history of genetic disorders.

Symptoms

The symptoms of Trisomy 18 can vary, but common characteristics include:

• Low birth weight
• Small size for gestational age
• Weak cry and poor sucking reflex
• Difficulty feeding
• Vomiting or regurgitation of food
• Slow growth and development
• Intellectual disability
• Physical abnormalities, such as:
• Small head size (microcephaly)
• Overlapping fingers
• Rocker-bottom feet
• Low-set ears
• Cleft lip and palate
• Organ abnormalities, such as:
• Heart defects
• Kidney problems
• Intestinal blockages

Diagnosis

Trisomy 18 can be diagnosed prenatally through:

• Chorionic villus sampling (CVS)
• Amniocentesis
• Ultrasound
• MATERNAL SERUM SCREENING (MSS)

After birth, a physical examination and genetic testing can confirm the diagnosis.

Treatments

Treatment for Trisomy 18 is primarily focused on managing symptoms and preventing complications. This may include:

• Surgical interventions to repair heart defects or other organ abnormalities
• Physical therapy to improve mobility and strength
• Occupational therapy to develop daily living skills
• Speech therapy to improve communication
• Pain management for discomfort or distress
• Nutritional support to ensure adequate nutrition and hydration
• Respiratory care to manage breathing difficulties

Prognosis

The prognosis for Trisomy 18 is generally poor, with a high mortality rate in the first year of life. Only about 5-10% of children with Trisomy 18 survive beyond their first birthday. Those who do survive often have significant developmental delays and disabilities.

Support and Resources

Families affected by Trisomy 18 can find support through organizations such as:

• The Trisomy 18 Foundation
• The National Organization on Rare Disorders (NORD)
• The Genetic Alliance

These organizations provide information, resources, and emotional support to families coping with this condition.