22q11.2 Deletion Syndrome (DiGeorge Syndrome)
What is DiGeorge syndrome?
22q11.2 deletion syndrome (22q11.2DS), also known as DiGeorge syndrome, is a genetic disorder that occurs when a small piece of one of the baby’s chromosomes – chromosome 22 – is missing.
This missing genetic material alters the way the body develops and functions, causing a wide range of physical characteristics, health problems and developmental issues.
22q11.2DS (DiGeorge syndrome) can affect almost every part of the body. While the impact on each child varies greatly, common complications include heart defects, a cleft palate, frequent infections, low calcium levels in the neonatal period, feeding difficulties, developmental delays, and mental health and behavioral issues.
Treatment is focused on each child’s symptoms. Early diagnosis and intervention are important to help optimize outcomes.
What causes 22q11.2 deletion syndrome (DiGeorge Syndrome)?
Typically, a baby is born with 46 chromosomes in every cell in their body, arranged in 23 matching pairs – one copy from the mother, the other from the father. These chromosomes contain our DNA which make up our genes, the instructions for the human body. Our genes are responsible for how we look and how our body develops and functions.
In babies with 22q11.2DS, a small piece of one copy of chromosome 22 is missing. That missing piece is estimated to contain 30 to 40 genes. Without those genes, or “instructions,” the baby doesn’t develop as expected, leading to the signs and symptoms associated with 22q11.2DS.
In most cases, 22q11.2DS (DiGeorge Syndrome)occurs randomly during conception or early fetal growth. In an estimated 7 percent of cases the condition is inherited from the mother or the father. Genetic counseling is recommended in all cases.
22q11.2DS is caused by a very specific region of chromosome 22 being absent. The name 22q11.2 refers to the chromosome affected (22) and the specific area on the 22nd chromosome where the piece is missing (a location known as q11.2).
How will 22q11.2 deletion syndrome affect my baby?
22q11.2DS (DiGeorge Syndrome) can cause a widely diverse group of symptoms. Each child will have their own unique set and severity of symptoms.
Common complications include:
- Heart defects, which can be severe including tetralogy of Fallot, truncus arteriosus, ventricular septal defect, or others
- Cleft palate
- Facial features such as almond-shaped eyes, hooded eyelids, small mouth and underdeveloped chin, small ears
- Frequent infections caused by immune system problems
- Low levels of calcium in the blood leading to seizures
- Feeding difficulties or gastrointestinal problems
- Speech difficulties
- Hearing loss
- Kidney abnormalities, including a malformed or missing kidney
- Spine abnormalities such as curvature of the spine (scoliosis)
- Developmental delays, including delayed growth and speech
- Learning disabilities
- Thrombocytopenia (low platelet count)
- Breathing difficulties caused by palate abnormalities
- Mild intellectual disability
- Increased risk of attention deficit hyperactivity disorder (ADHD), autism and mental health issues, including schizophrenia
22q11.2DS (DiGeorge Syndrome) may be suspected during pregnancy based on a family history and/or prenatal imaging that detects a cardiac defect in combination with other abnormalities such as a cleft palate, skeletal anomalies, kidney anomalies, and polyhydramnios (too much amniotic fluid).
Testing to confirm the diagnosis involves taking a sample of genetic material and analyzing the chromosomes. Routine diagnostic tests include:
- Chorionic villus sampling (CVS) – genetic testing of a sample of tissue taken from the placenta in the first trimester
- Amniocentesis – genetic testing of a sample of the amniotic fluid taken from the womb in the second trimester
These diagnostic tests carry a small risk of complications, including the risk of pregnancy loss. Talk with your doctor about the risks involved before undergoing testing.
At birth or during childhood
22q11.2DS may be suspected at birth if symptoms and features associated with the disorder are evident. Genetic testing can confirm the diagnosis.
In some cases, the disorder may not be detected until later in childhood, for example if speech is delayed, or during a routine pediatric well-visit that identifies health issues associated with 22q11.2DS. Some parents are not aware they carry the same deletion until their child receives a diagnosis of 22q11.2DS.
Specialized Prenatal Evaluation and Care
If 22q11.2DS (DiGeorge syndrome) is suspected or diagnosed during pregnancy, you may be referred to a fetal center for a comprehensive evaluation and specialized care.
At Texas Children’s Fetal Center, we arrange for you to visit as quickly as possible with a team of specialists experienced in diagnosing and treating these chromosomal disorders, including maternal-fetal medicine physicians (OB/GYNs specializing in high-risk pregnancies), fetal imaging experts, geneticists and genetic counselors, neonatologists, and pediatric cardiologists.
Additional testing may be performed using state-of-the-art imaging technologies and techniques, including:
- High-resolution anatomy ultrasound to evaluate the baby’s condition and identify any associated abnormalities
- Ultra-fast MRI for a more detailed view of fetal anatomy
- Fetal echocardiogram to assess the baby’s heart structure and function
- Amniocentesis and chromosomal analysis to diagnose chromosomal disorders
Our specialists will then meet with you about the results, discuss treatment recommendations, and answer any questions your family has, to help you make the most informed decisions.
A diagnosis during pregnancy enables your family and your healthcare team to plan ahead for the specialized care your child may require at birth, for the best possible outcomes.
Pregnancy and Delivery
Mother and baby will be closely monitored throughout pregnancy with regular ultrasounds to assess fetal growth and watch for signs of complications.
For the best possible outcomes, we recommend delivery at a center with the resources and expertise to treat these complex conditions, including the highest level neonatal intensive care unit (NICU) and the highest quality congenital heart program, if needed.
Delivery and postnatal care should be carefully planned and coordinated with a team of maternal-fetal medicine physicians, neonatologists, and pediatric specialists experienced in working together to treat babies with chromosomal disorders.
Our Fetal Center team works closely with pediatric experts from Texas Children’s Hospital, avoiding the need to transfer your newborn during the critical postnatal period. Texas Children’s is consistently ranked one of the best children’s hospitals in the nation by U.S. News & World Report, and is a national leader in pediatric cardiology and heart surgery.
Treatment for 22q11.2DS (DiGeorge Syndrome) depends on each child’s symptoms and complications. Early intervention is key to optimizing outcomes.
In general, treatment strategies for children with 22q11.2DS may include:
- Surgery to repair a congenital heart defect
- Surgery to repair a cleft palate/cleft lip
- Tube feeding for babies with severe feeding problems
- Calcium supplements to treat low calcium levels
- Treatment of infections and immune system complications
- Speech therapy to help with language delays
- Physical and occupational therapy to help children meet developmental milestones
- Support for learning difficulties
- Mental health care for behavioral or mental health concerns
- Regular checkups for early detection of new health complications or developmental issues as the child ages
Postnatal Care Team
Children with 22q11.2DS (DiGeorge Syndrome) typically require coordinated care by a diverse team of healthcare providers.
While the needs vary for each child, postnatal care team members may include:
- Primary care pediatrician
- Geneticist/genetic counselor
- Pediatric cardiologist
- Pediatric plastic and craniofacial surgeon
- Pediatric endocrinologist (hormone specialist)
- Developmental pediatrician
- Otolaryngologist (ear, nose and throat specialist)
- Nephrologist (kidney specialist)
- Speech pathologist
- Physical and occupational therapist
- Social worker
- Pediatric psychologist
Why Texas Children’s Fetal Center?
- A single location for expert maternal, fetal, and pediatric care. At Texas Children’s Hospital, mother and baby receive the specialized care required for the diagnosis and treatment of 22q11.2DS all in one location, including immediate access to our level IV NICU, if needed.
- A skilled, experienced team with proven outcomes. We have a dedicated team of maternal-fetal medicine specialists, fetal imaging experts, geneticists and genetic counselors, neonatologists, and pediatric specialists who work in concert to care for you and your baby every step of the way, using proven protocols we’ve developed over the years. With their combined expertise and unified approach, this team offers the best possible care for babies with 22q11.2DS.
- We care for your child’s needs at every stage of life. Our comprehensive approach starts with your first prenatal visit and continues through delivery, postnatal care, childhood and adolescence, thanks to one of the nation’s leading teams of fetal and pediatric specialists for the care and treatment of chromosomal disorders.
For more information or to schedule an appointment,
call Texas Children’s Fetal Center at 832-822-2229 or 1-877-FetalRx (338-2579) toll-free.
Our phones are answered 24/7. Immediate appointments are often available.