DiGeorge Syndrome (22q11.2 Deletion Syndrome)

DiGeorge syndrome, also known as 22q11.2 deletion syndrome, is a rare genetic disorder that occurs when a small part of chromosome 22 is deleted. This deletion affects the development of various body systems and can lead to a range of physical, developmental, and health problems.

Causes and Risk Factors

The cause of DiGeorge syndrome is a deletion of a small segment of chromosome 22, specifically at position q11.2. This deletion occurs spontaneously in most cases, meaning it is not inherited from either parent. However, in some cases, the deletion can be inherited from a parent who carries a balanced translocation or deletion.

Symptoms and Characteristics

Individuals with DiGeorge syndrome may exhibit a range of symptoms and characteristics, including:

• Heart defects, such as tetralogy of Fallot, truncus arteriosus, and interrupted aortic arch
• Cleft palate or velopharyngeal insufficiency (VPI)
• Immunodeficiency due to thymic hypoplasia or aplasia, leading to increased susceptibility to infections
• Hypocalcemia (low calcium levels) and hypoparathyroidism (underactive parathyroid glands)
• Developmental delays and learning disabilities
• Facial abnormalities, such as a long face, prominent forehead, and small ears
• Hearing loss or vision problems

Diagnosis

DiGeorge syndrome is typically diagnosed through a combination of physical examination, medical history, and genetic testing. The diagnosis may be suspected based on the presence of characteristic facial features, heart defects, or immunodeficiency.

Genetic testing, such as fluorescence in situ hybridization (FISH) or chromosomal microarray analysis, can confirm the diagnosis by detecting the deletion at chromosome 22q11.2.

Treatment and Management

Treatment for DiGeorge syndrome depends on the individual's specific symptoms and characteristics. It may involve a multidisciplinary team of healthcare professionals, including cardiologists, immunologists, endocrinologists, and speech therapists.

Interventions may include:

• Surgical repair of heart defects
• Cleft palate repair and speech therapy for VPI
• Immunoglobulin replacement therapy to boost the immune system
• Calcium and vitamin D supplements to manage hypocalcemia
• Developmental therapies, such as physical, occupational, and speech therapy, to support developmental progress

Prognosis and Outlook

The prognosis for individuals with DiGeorge syndrome varies depending on the severity of their symptoms and the effectiveness of treatment. With proper management and care, many people with DiGeorge syndrome can lead active and fulfilling lives.

However, some individuals may experience significant health challenges and developmental delays, which can impact their quality of life and life expectancy.