The association of progressive extrapyramidal neurologic
disorder presenting in teenagers or even earlier and mild form of
Parkinson disease. Characterized by tremor, bradykinesia, dysarthria,
rigidity, and fixed facies. The disorder may be familial (genetically
transmitted) or secondary to other heredodegenerative disorders, such as
Corpus Striatum Syndrome; Dyssynergia Cerebellaris
Myoclonica; Hunt Paralysis; Hunt Syndrome II; Juvenile Parkinson Disease of
Hunt; Willige-Hunt Syndrome.
Degeneration of lenticular nuclei. First clinical report
by Huchard in 1875.
In Parkinson disease cases, 25% are genetically
inherited, of which a small number of cases are represented by juvenile
Familial forms may be transmitted as an
autosomal dominant or autosomal recessive trait. The recessive form, called
“Parkin type of juvenile Parkinson disease,” is caused by mutations within
the Parkin gene PARK2, which is located on chromosome 6q25.2-q27. The dominant
form is caused by mutations in the alpha-synuclein gene PARK1 (on chromosome
4q21); a fragment of the product of this gene is a known constituent of
Alzheimer disease plaques. A few dominant forms of the disease involve other
dominant loci, including ubiquitin cyclohydrolase L1 (UCHL1) on chromosome
2p12 (PARK3) and chromosome 4p (PARK4). These enzymes are part of the ubiquitin
proteolytic system (UPS), which plays a central role in the regulation of
many cellular processes, including removal of abnormal, misfolded, or
Whatever the genetic transmission, the disease is
associated with loss of dopaminergic neurons in the substantia nigra and
dopamine deficiency in the striatum. There is a subsequent increase in the
activity of the subthalamic nucleus and the globus pallidus, which is
responsible for the extrapyramidal movements. Other nondopaminergic neurons
are affected (serotonin, norepinephrine), the depletion of which causes
psychological and behavioral disorders.
Clinical diagnosis. An antiserum that is immunoreactive
to the Parkin immunizing peptide by enzyme-linked immunoabsorbent assay
(ELISA) is available.
Clinical features are very similar to the adult
form of parkinsonism and begins between 5 and 15 years of age. Tremors appear first, then rigidity, dyskinesia, and unexpressive face. Disturbed gait and
dysarthria. Ameliorated by l-dopa (levo-dopamine), monoamine oxidase
(MAO) inhibitors, and anticholinergic agents.
Check carefully the child's
medication (l-dopa and MAO inhibitors). Do not stop medication; give
the morning dose of l-dopa. l-Dopa has a short half-life and
stopping it for more than 6 to 12 hours can lead to severe muscular rigidity
and worsening of the ventilation.
Light anesthesia can favor muscular
rigidity. Prevent hyperventilation (hypocarbia) which may trigger seizures. Monitor
carefully the hemodynamics because of MAO inhibitors.
There is frequent interaction
between drugs commonly used to treat the condition and anesthetic agents.
Drugs with antidopaminergic properties such as butyrophenones (DHBP) and
phenothiazines, as well as alfentanil (dystonia), should be avoided.
Ketamine is controversial because it may enhance hypertension and
tachycardia. Theoretically, the association ...