# Handbook of Genetic Counseling/Cerebral Palsy

Cerebral palsy

## Contracting

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## Etiology

* Heterogeneous group of conditions usually leading to ataxia
* Sometimes inherited in autosomal dominant, autosomal recessive, or X-linked form in familial cerebellar hypoplasia
| Inheritance | Condition | Features |
| Autosomal Dominant | Cerebellar Vermis Aplasia | Female Sex Bias |
| Autosomal recessive | Cerebellar hypoplasia with or without retinal pigment abnormality | Presents in infancy |
| | Cerebellar granule cell hypoplasia | 2 or more types, one with severe microcephaly |
| | Cerebellar ataxia with neuronal migration defect | Absence of muscle disease |
| | Pontoneocerebellar atrophy with extrapyramidal dyskinesia | |
| | Fatal infantile olivopontocerebellar hypoplasia | Neronal loss in olives and pontine nuclei, white matter gliosis, microcephaly |
| | Cerebellar atrophy with infantile striatal degeneration | Progressive epilepsy, mental handicap, death after febrile illness |
| | Gillespie syndrome | Cerebellar atrophy, aniridia, mental handicap |
| | Cerebellar atrophy and anterior horn cell disease | Neuromuscular condition similar to type I SMA |
| | Cerebellar hypoplasia with progressive pancytopenia (Hyoyeraal-Hreidarsson) | Males with growth retardation, microcephaly, pancytopaenia (X-linked?) |
| | Cerebellar atrophy, renal and liver disease | Carbohydrate-deficient glycoprotein syndrome |
| X-linked (possibly) | Paine syndrome | Hypoplasia of pons and olives, microcephaly, epilepsy, mental handicap, spasticity |
| | X-linked dominant vermis aplasia | Preponderance of female-to-female transmission |
| | Cerebellar vermis aplasia, holoprosencephaly syndrome | Male sibs affected by holoprosencephaly and/or vermis aplasia |
** Congenital and childhood-onset ataxias tend to be autosomal recessive
** Adult-onset conditions tend to be autosomal dominant
* May also be due to teratogenic insults
** Methymercury
** Retinoic acid
** Anticonvulsants
* Most common cause is hypoxic/ischemic injury in perinatal period or early childhood
** Anoxia
** Trauma to the brain at birth
* Can be caused by cerebral injury later in life

## Clinical Features

* Several classes with different features
* Spastic diplegia
** Onset several weeks or months after birth
*** Delay in normal development, especially motor skills
*** Results from prenatal or perinatal insult
** Walking attempted much later and results in characteristic stance and gait
*** Legs advanced stiffly in short steps like arc of circle
*** May have scissors gait with crossing over of legs
*** Lower legs splayed out, feet flexed and turned in, heels not touching ground
*** Posture alternates between extremes of supination and pronation
*** Walking accompanied often by rotary movements of neck and facial grimacing
** Legs short and small but muscles not atrophic
** Arms may also be mildly affected
* Hemiplegia
** Difference in function of right and left extremities noticed after birth or 6-12 months
** Accounts for about 1/3 of children with cerebral palsy
** Affects arms first, noticed in legs when learning to walk
** Mental defects depend on whether brain lesion confined to one hemisphere
** Convulsions (35-50%)
** Seizures may accompany onset if develops during childhood
*** Usually limited to hemiplegic side of body
*** May persist throughout life
* Double hemiplegia
** Occurs less frequently than hemiplegia
** Bilateral weakness of face, arms, and legs
** Begins at any age due to acquired cerebral disease
*** May be due to bilateral cerebral lesion or high cervical cord lesion
*** May also be produced in infant by fracture-dislocation of cervical spine by breech delivery
** Arms severely affected
* Congenital choreoathetosis
** Recognized after several months or a year
** Causes some combination of chorea, athetosis, ballismus, myoclonus, and dystonia
** Causes defect in voluntary movement
*** May be mild resulting in "fidgets"
*** May be severe, intense involuntary movements
*** Even with rehabilitation, the most severe rarely achieve enough motor control to live independent life
** Intelligence may not be affected
* Kernicterus
** Was common when postnatal serum bilirubin was kept below 15 mg/dL
** Majority of infants die within 1 or 2 years
** Survivors usually mentally retarded, deaf, and totally unable to sit, stand, or walk
*** Several patients reportedly were not mentally retarded and learned to walk backwards
*** Have rigid limbs

## Management/Treatment Options

* Outcome depends on severity of associated intellectual handicaps
* Early application of stretching to prevent contractures
* Orthopedic appliances and surgical procedures to improve mobility
* Special education to help with motor problems and intellectual involvement
* Prevention is great challenge
** Prevention of kernicterus by phototherapy has helped
** Providing low-birth weight infants with extra care may help
*** More prone to respiratory distress
*** Must provide good surveillance of respiratory function

## Differential Diagnosis

* Leukodystrophy - spinal tap showing elevated spinal fluid indicates leukodystrophy
* Hydrocephaly if child has large head
* Tumor of cerebral hemisphere - disease is progressive
* Spinal cord lesions - weakness limited to lower extremities
* Muscular dystrophy - tendon reflexes would be normal
* Ataxia telangiectasia

## Recurrence Risks

* Depends if cause of cerebral palsy can be determined
* Autosomal recessive
** Each pregnancy from heterozygote parents has 25% risk of child being affected
** Each pregnancy has 50% risk of being carrier
* Autosomal dominant
** Each child born to affected parent has 50% chance of being affected
** May also occur due to new mutation so low recurrence risk
* X-linked
** Sons of affected males not affected
** Daughters of affected males must be affected
** Daughters of carrier females 50% risk of being carriers
** Sons of carrier females 50% risk of being affected
* Most cases probably caused by hypoxic or ischemic injury to brain so recurrence risk is low

## Psychosocial Issues

* Parental guilt
* Burden of disease that requires daily management
* Social stigma
* Financial pressures, disruption of daily activities for special therapies, orthotics, or other needs
* Potential need for lifetime care

## References

* "Abnormalities of Motor Function (Cerebral Palsy)." Principles of Internal Medicine (1994): 2342.
* "Cerebellar Hypoplasias." Principles and Practice of Medical Genetics (1997): 2154-2156.
* "Cerebral Palsy (Little Disease)." Textbook of Pediatrics (1979): 1759-1761.

## Notes

The information in this outline was last updated in 2002.