DiGeorge Syndrome Flashcards
What is the frequency of DiGeorge Syndrome?
1/4000 live births.
True or false: DiGeorge is the second most common cause of developmental delay and congenital heart disease after Down Syndrome
True
What causes DiGeorge Syndrome?
Deletion of 22q11.2 (3MB interstitial deletion on band 11 of the long arm of chromosome 22)
What does a deletion of 22q11.2 cause from a fetal development standpoint?
Deletion leads to disturbance of cervical neural crest migration into the pharyngeal arches/pouches.
How is DiGeorge syndrome inherited?
Typically a de novo mutation, but can be inherited in an AD fashion in 10% of cases (Mothers>fathers)
What does CATCH22 stand for?
C- cardiac abnormalities A- abnormal facies T- T-cells decreased C- Cleft palate H- Hypocalcemia 22q11.2 deletion
What is the main group of cardiac abnormalities seen in DiGeorge syndrome? Name 3 examples.
75% of patients have conotruncal malformations including:
- Tetralogy of Fallot
- Truncus arteriosis
- Interrupted aortic arch
Name 6 characteristic facial features of DiGeorge Syndrome
- Short philtrium
- Small chin/mouth
- Prominent nose
- Long face
- Protruding or microcytic ears
- Narrow almond shaped eyes
Why do children with 22q11 have impaired T cell production?
Due to hypoplasia/atresia of the thymus.
Recurrent infections, and increased risk of autoimmune diseases like JIA, ITP, hemolytic anemia
Name 8 ENT features of 22q11
- Cleft palate/velopharyngeal insufficiency
- Hypernasal voice
- Poor sucking/regurgitation
- Bifid uvula
- Nasopharynx hypoplasia
- Frequent ear infxns
- Conductive hearing loss
- Laryngeal abnormalities
Name 3 endocrine features of DiGeorge
- Hypocalcemia caused by parathyroid hypoplasia (often self limited–>resolves by 1 yr age)
- Short stature (small % have GH deficiency)
- Hypothyroidism
Name 8 Mental Health conditions individuals with 22q11 are at increased risk for
- Average IQ 75 (range 50-100)
- Learning disabilities (90%)
- Autism
- ADHD
- Schizophrenia
- Bipolar
- Depression
- Anxiety
How do you diagnose DiGeorge syndrome?
Microarray
How often should individual with DiGeorge be tested for hypocalcemia?
every 3-6mos as an infant, then every 5 yrs through childhood, and every 1-2 yrs as an adolescent/adult.
What 6 things should be tested/monitored in individuals w 22q11 other than calcium?
- Thyroid testing q yearly
- CBC q yearly
- Immunology-testing at birth then prior to live vaccines
- Cervical spine Xray every 4 years and prior to neck manipulation
- Echo and renal US at diagnosis
- Monitor hearing/vision
