Handbook of Genetic Counseling/Cleft Palate - Pierre Robin Sequence-2
Pierre Robin Sequence
Contracting
edit- How have things been going since your last visit to genetics?
- What questions or concerns would you like to discuss today?
- Set agenda for session
Etiology
edit- Association of micrognathia, cleft palate, and glossoptosis
- Multiple anomalies caused secondarily by a structural anomaly
- Micrognathia or retrognathia at 9-11 weeks of embryonic development prevents tongue from descending from between palatal shelves
- Tongue prevents palatal shelves from growing together horizontally and fusing
- Causes tongue to be displaced, blocking airway
- About 80% of cases may be caused by a multiple anomaly syndrome
- 34% of Pierre Robin due to Stickler syndrome
- Due to mutations in COL2A1 gene usually at 12q13
- Also could be due to mutations in COL11A1 (1p21) or COL11A2 (6p21)
- Autosomal dominant disorder with 50% recurrence risk
- 11% of Pierre Robin due to VCF
- Deletion of 22q11
- Recurrence risk 50% if one parent has deletion
- Many other single gene disorders, some X-linked recessive disorders, recessive disorders
- Teratogenic exposure
- Fetal alcohol syndrome
- Fetal hydantoin syndrome
- Retinoic acid embryopathy
- Isolated Pierre Robin sequence
- May be due to fetal crowding due to presence of multiple fetuses, abnormal fetal position, uterine anomalies, or oligohydramnios
- Associated deformities may also occur
- Multifactorial inheritance
- Recurrence risk if one child with cleft palate 3-5%
- Recurrence risk if two children with cleft palate 10-12%
- Affected individual has 3-5% chance of having a child with cleft palate
- Incidence is about 1/2500 births for cleft palate
Clinical Features and Natural History
edit- Craniofacial
- Often U-shaped cleft involving both hard and soft palate
- Small and symmetrically receded mandible
- May cause dental crowding
- Jaw may "catch up" in adolescence if due to mechanical constraint
- Flattened base of nose
- Growth and Feeding difficulties (long-term feeding problems 50%)
- Failure to thrive evident in neonatal period
- Poor suck due to cleft palate
- Inability to nurse, irritability, aspiration
- Often due to respiratory difficulties
- Respiratory complications
- Upper airway obstruction often present at birth or shortly after
- Deep pectus excavatum
- Cyanosis not common but may occur
- May be due to glossoptosis obstructing the epiglottis
- Complications of continuing airway disorder may include sudden death, failure to thrive, persistent deformation of sternum, decreased pulmonary function, cognitive effects of hypoxia
- Ears and Hearing
- Middle ear disease due to cleft palate
- Chronic ear infections may lead to conductive hearing loss
- Cognitive and motor development normal in isolated Pierre Robin sequence
Testing Options
edit- Genetic testing may be offered if genetic syndrome is suspected
- Chromosome analysis
- FISH for deletion of 22q11
- DNA testing for mutations in collagen genes indicated in Stickler syndrome
- Level II ultrasound prenatally at 18-20 weeks gestation for cleft palate but difficult to identify
Management and Treatment
edit- Overcoming feeding difficulties
- Important that baby learns to actively suckle
- Establish feeding routine that requires short feeding time
- Use special cleft palate nursing bottle
- Reflux may be treated with medication or regular breaks to burp
- May require NG tube or g-tube
- Cleft palate repaired surgically 9-18 months
- Weight, size of airway are factors in when surgery performed
- Must be sure lower jaw is wide enough to accommodate tongue once palate repaired
- Usually requires 1-3 day hospital stay
- Jaw distraction surgery now being performed on infants in some hospitals
- Tracheostomy may e required if severe airway issues
- Special services
- Speech therapy to prevent speech and language delays
- May require IEP from school or other services, particularly if caused by underlying genetic syndrome
- Chronic middle ear infections treated aggressively with antibiotics or PE tubes to avoid conductive hearing loss, speech and language delays
Differential Diagnosis
edit- Most commonly associated with VCF or Stickler syndrome
- Some other associated syndromes include Myotonic Dystrophy, Campomelic dysplasia, Lenz syndrome, Nager syndrome, Treacher Collins syndrome, and Turner syndrome
Psychosocial
edit- Frustration, impatience due to feeding difficulties in newborns
- Difficulty relating to baby due to physical appearance, inability to breastfeed
- Guilt, anxiety, depression, anger about diagnosis
- Assess support system
Resources
edit- Pierre Robin Network
- American Cleft Palate-Craniofacial Association
- http://www.cleft.com/
- 800-242-5338
References
edit- "Orofacial Clefting Syndromes: General Aspects." Syndromes of the Head and Neck (1990) 693-704.
- "Pierre Robin Fact Sheet." Pierre Robin Network. http://www.pierrerobin.org/
- Shprintzen RJ. "Robin Sequence." Management of Genetic Syndromes (2001) 323-336.
Notes
editThe information in this outline was last updated in 2000.